Figure 1 | Laboratory channel dimensions.

강화된 조도 계수 및 인버트 레벨 변화가 있는 90도 측면 턴아웃에서의 유동에 대한 실험적 및 수치적 연구

Experimental and numerical study of flow at a 90 degree lateral turnout with enhanced roughness coefficient and invert level changes

Maryam Bagheria, Seyed M. Ali Zomorodianb, Masih Zolghadrc, H. Md. Azamathulla d,*
and C. Venkata Siva Rama Prasade
a Hydraulic Structures, Department of Water Engineering, Shiraz University, Shiraz, Iran
b Department of Water Engineering, College of Agriculture, Shiraz University, Shiraz, Iran
c Department of Water Sciences Engineering, College of Agriculture, Jahrom University, Jahrom, Iran
d Civil & Environmental Engineering, The University of the West Indies, St. Augustine Campus, Port of Spain, Trinidad
e Department of Civil Engineering, St. Peters Engineering College, Hyderabad, India
*Corresponding author. E-mail: azmatheditor@gmail.com

ABSTRACT

측면 분기기(흡입구)의 상류측에서 유동 분리는 분기기 입구에서 맴돌이 전류를 일으키는 중요한 문제입니다. 이는 흐름의 유효 폭, 분기 용량 및 효율성을 감소시킵니다. 따라서 분리구역의 크기를 파악하고 그 크기를 줄이기 위한 방안을 제시하는 것이 필수적이다.

본 연구에서는 분리 구역의 크기를 줄이기 위한 방법으로 분출구 입구에 7가지 유형의 조면화 요소와 4가지 다른 방류가 있는 3가지 다른 베드 인버트 레벨의 설치(총 84회 실험)를 조사했습니다. 또한 3D 전산 유체 역학(CFD) 모델을 사용하여 분리 구역의 흐름 패턴과 치수를 평가했습니다.

결과는 조도 계수를 향상시키면 분리 영역 치수를 최대 38%까지 줄일 수 있는 반면 드롭 구현 효과는 사용된 조도 계수에 따라 이 영역을 다르게 축소할 수 있음을 보여주었습니다. 두 방법을 결합하면 분리 구역 치수를 최대 63%까지 줄일 수 있습니다.

Flow separation at the upstream side of lateral turnouts (intakes) is a critical issue causing eddy currents at the turnout entrance. It reduces the effective width of flow, turnout capacity and efficiency. Therefore, it is essential to identify the dimensions of the separation zone and propose remedies to reduce its dimensions.

Installation of 7 types of roughening elements at the turnout entrance and 3 different bed invert levels, with 4 different discharges (making a total of 84 experiments) were examined in this study as a method to reduce the dimensions of the separation zone. Additionally, a 3-D Computational Fluid Dynamic (CFD) model was utilized to evaluate the flow pattern and dimensions of the separation zone.

Results showed that enhancing the roughness coefficient can reduce the separation zone dimensions up to 38% while the drop implementation effect can scale down this area differently based on the roughness coefficient used. Combining both methods can reduce the separation zone dimensions up to 63%.

Key words

discharge ratio, flow separation zone, intake, three dimensional simulation

Experimental and numerical study of flow at a 90 degree lateral turnout with enhanced
roughness coefficient and invert level changes
Experimental and numerical study of flow at a 90 degree lateral turnout with enhanced roughness coefficient and invert level changes
Figure 1 | Laboratory channel dimensions.
Figure 1 | Laboratory channel dimensions.
Figure 2 | Roughness plates.
Figure 2 | Roughness plates.
Figure 4 | Effect of roughness on separation zone dimensions.
Figure 4 | Effect of roughness on separation zone dimensions.
Figure 10 | Comparision of the vortex area (software output) for three roughnesses (0.009, 0.023 and 0.032).
Figure 10 | Comparision of the vortex area (software output) for three roughnesses (0.009, 0.023 and 0.032).
Figure 11 | Comparison of vortex area in 3D mode (tecplot output) with two roughnesses (a) 0.009 and (b) 0.032.
Figure 11 | Comparison of vortex area in 3D mode (tecplot output) with two roughnesses (a) 0.009 and (b) 0.032.
Figure 12 | Velocity vector for flow condition Q¼22 l/s, near surface.
Figure 12 | Velocity vector for flow condition Q¼22 l/s, near surface.

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Figure 14. Defects: (a) Unmelt defects(Scheme NO.4);(b) Pores defects(Scheme NO.1); (c); Spattering defect (Scheme NO.3); (d) Low overlapping rate defects(Scheme NO.5).

Molten pool structure, temperature and velocity
flow in selective laser melting AlCu5MnCdVA alloy

용융 풀 구조, 선택적 온도 및 속도 흐름 레이저 용융 AlCu5MnCdVA 합금

Pan Lu1 , Zhang Cheng-Lin2,6,Wang Liang3, Liu Tong4 and Liu Jiang-lin5
1 Aviation and Materials College, Anhui Technical College of Mechanical and Electrical Engineering, Wuhu Anhui 241000, People’s
Republic of China 2 School of Engineering Science, University of Science and Technology of China, Hefei Anhui 230026, People’s Republic of China 3 Anhui Top Additive Manufacturing Technology Co., Ltd., Wuhu Anhui 241300, People’s Republic of China 4 Anhui Chungu 3D Printing Institute of Intelligent Equipment and Industrial Technology, Anhui 241300, People’s Republic of China 5 School of Mechanical and Transportation Engineering, Taiyuan University of Technology, Taiyuan Shanxi 030024, People’s Republic of
China 6 Author to whom any correspondence should be addressed.
E-mail: ahjdpanlu@126.com, jiao__zg@126.com, ahjdjxx001@126.com,tongliu1988@126.com and liujianglin@tyut.edu.cn

Keywords

SLM, molten pool, AlCu5MnCdVA alloy, heat flow, velocity flow, numerical simulation

Abstract

선택적 레이저 용융(SLM)은 열 전달, 용융, 상전이, 기화 및 물질 전달을 포함하는 복잡한 동적 비평형 프로세스인 금속 적층 제조(MAM)에서 가장 유망한 기술 중 하나가 되었습니다. 용융 풀의 특성(구조, 온도 흐름 및 속도 흐름)은 SLM의 최종 성형 품질에 결정적인 영향을 미칩니다. 이 연구에서는 선택적 레이저 용융 AlCu5MnCdVA 합금의 용융 풀 구조, 온도 흐름 및 속도장을 연구하기 위해 수치 시뮬레이션과 실험을 모두 사용했습니다.

그 결과 용융풀의 구조는 다양한 형태(깊은 오목 구조, 이중 오목 구조, 평면 구조, 돌출 구조 및 이상적인 평면 구조)를 나타냈으며, 용융 풀의 크기는 약 132 μm × 107 μm × 50 μm였습니다. : 용융풀은 초기에는 여러 구동력에 의해 깊이 15μm의 깊은 오목형상이었으나, 성형 후기에는 장력구배에 의해 높이 10μm의 돌출형상이 되었다. 용융 풀 내부의 금속 흐름은 주로 레이저 충격력, 금속 액체 중력, 표면 장력 및 반동 압력에 의해 구동되었습니다.

AlCu5MnCdVA 합금의 경우, 금속 액체 응고 속도가 매우 빠르며(3.5 × 10-4 S), 가열 속도 및 냉각 속도는 각각 6.5 × 107 K S-1 및 1.6 × 106 K S-1 에 도달했습니다. 시각적 표준으로 표면 거칠기를 선택하고, 낮은 레이저 에너지 AlCu5MnCdVA 합금 최적 공정 매개변수 창을 수치 시뮬레이션으로 얻었습니다: 레이저 출력 250W, 부화 공간 0.11mm, 층 두께 0.03mm, 레이저 스캔 속도 1.5m s-1 .

또한, 실험 프린팅과 수치 시뮬레이션과 비교할 때, 용융 풀의 폭은 각각 약 205um 및 약 210um이었고, 인접한 두 용융 트랙 사이의 중첩은 모두 약 65um이었다. 결과는 수치 시뮬레이션 결과가 실험 인쇄 결과와 기본적으로 일치함을 보여 수치 시뮬레이션 모델의 정확성을 입증했습니다.

Selective Laser Melting (SLM) has become one of the most promising technologies in Metal Additive Manufacturing (MAM), which is a complex dynamic non-equilibrium process involving heat transfer, melting, phase transition, vaporization and mass transfer. The characteristics of the molten pool (structure, temperature flow and velocity flow) have a decisive influence on the final forming quality of SLM. In this study, both numerical simulation and experiments were employed to study molten pool structure, temperature flow and velocity field in Selective Laser Melting AlCu5MnCdVA alloy. The results showed the structure of molten pool showed different forms(deep-concave structure, double-concave structure, plane structure, protruding structure and ideal planar structure), and the size of the molten pool was approximately 132 μm × 107 μm × 50 μm: in the early stage, molten pool was in a state of deep-concave shape with a depth of 15 μm due to multiple driving forces, while a protruding shape with a height of 10 μm duo to tension gradient in the later stages of forming. The metal flow inside the molten pool was mainly driven by laser impact force, metal liquid gravity, surface tension and recoil pressure. For AlCu5MnCdVA alloy, metal liquid solidification speed was extremely fast(3.5 × 10−4 S), the heating rate and cooling rate reached 6.5 × 107 K S−1 and 1.6 × 106 K S−1 , respectively. Choosing surface roughness as a visual standard, low-laser energy AlCu5MnCdVA alloy optimum process parameters window was obtained by numerical simulation: laser power 250 W, hatching space 0.11 mm, layer thickness 0.03 mm, laser scanning velocity 1.5 m s−1 . In addition, compared with experimental printing and numerical simulation, the width of the molten pool was about 205 um and about 210 um, respectively, and overlapping between two adjacent molten tracks was all about 65 um. The results showed that the numerical simulation results were basically consistent with the experimental print results, which proved the correctness of the numerical simulation model.

Figure 1. AlCu5MnCdVA powder particle size distribution.
Figure 1. AlCu5MnCdVA powder particle size distribution.
Figure 2. AlCu5MnCdVA powder
Figure 2. AlCu5MnCdVA powder
Figure 3. Finite element model and calculation domains of SLM.
Figure 3. Finite element model and calculation domains of SLM.
Figure 4. SLM heat transfer process.
Figure 4. SLM heat transfer process.
Figure 14. Defects: (a) Unmelt defects(Scheme NO.4);(b) Pores defects(Scheme NO.1); (c); Spattering defect (Scheme NO.3); (d) Low
overlapping rate defects(Scheme NO.5).
Figure 17. Two-pass molten tracks overlapping for Scheme NO.2.
Figure 17. Two-pass molten tracks overlapping for Scheme NO.2.

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Development of macro-defect-free PBF-EB-processed Ti–6Al–4V alloys with superior plasticity using PREP-synthesized powder and machine learning-assisted process optimization

Development of macro-defect-free PBF-EB-processed Ti–6Al–4V alloys with superior plasticity using PREP-synthesized powder and machine learning-assisted process optimization

Yunwei GuiabKenta Aoyagib Akihiko Chibab
aDepartment of Materials Processing, Graduate School of Engineering, Tohoku University, 6-6 Aramaki Aza Aoba, Aoba-ku, Sendai, 980-8579, Japan
bInstitute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan

Received 14 October 2022, Revised 23 December 2022, Accepted 3 January 2023, Available online 5 January 2023.Show lessAdd to MendeleyShareCite

https://doi.org/10.1016/j.msea.2023.144595Get rights and content

Abstract

The elimination of internal macro-defects is a key issue in Ti–6Al–4V alloys fabricated via powder bed fusion using electron beams (PBF-EB), wherein internal macro-defects mainly originate from the virgin powder and inappropriate printing parameters. This study compares different types powders by combining support vector machine techniques to determine the most suitable powder for PBF-EB and to predict the processing window for the printing parameters without internal macro-defects. The results show that powders fabricated via plasma rotating electrode process have the best sphericity, flowability, and minimal porosity and are most suitable for printing. Surface roughness criterion was also applied to determine the quality of the even surfaces, and support vector machine was used to construct processing maps capable of predicting a wide range of four-dimensional printing parameters to obtain macro-defect-free samples, offering the possibility of subsequent development of Ti–6Al–4V alloys with excellent properties. The macro-defect-free samples exhibited good elongation, with the best overall mechanical properties being the ultimate tensile strength and elongation of 934.7 MPa and 24.3%, respectively. The elongation of the three macro-defect-free samples was much higher than that previously reported for additively manufactured Ti–6Al–4V alloys. The high elongation of the samples in this work is mainly attributed to the elimination of internal macro-defects.

Introduction

Additive manufacturing (AM) technologies can rapidly manufacture complex or custom parts, reducing process steps and saving manufacturing time [[1], [2], [3], [4]], and are widely used in the aerospace, automotive, and other precision industries [5,6]. Powder bed fusion using an electron beam (PBF-EB) is an additive manufacturing method that uses a high-energy electron beam to melt metal powders layer by layer to produce parts. In contrast to selective laser melting, PBF-EB involves the preparation of samples in a high vacuum environment, which effectively prevents the introduction of impurities such as O and N. It also involves a preheating process for the print substrate and powder, which reduces residual thermal stress on the sample and subsequent heat treatment processes [[2], [3], [4],7]. Due to these features and advantages, PBF-EB technology is a very important AM technology with great potential in metallic materials. Moreover, PBF-EB is the ideal AM technology for the manufacture of complex components made of many alloys, such as titanium alloys, nickel-based superalloys, aluminum alloys and stainless steels [[2], [3], [4],8].

Ti–6Al–4V alloy is one of the prevalent commercial titanium alloys possessing high specific strength, excellent mechanical properties, excellent corrosion resistance, and good biocompatibility [9,10]. It is widely used in applications requiring low density and excellent corrosion resistance, such as the aerospace industry and biomechanical applications [11,12]. The mechanical properties of PBF-EB-processed Ti–6Al–4V alloys are superior to those fabricated by casting or forging, because the rapid cooling rate in PBF-EB results in finer grains [[12], [13], [14], [15], [16], [17], [18]]. However, the PBF-EB-fabricated parts often include internal macro-defects, which compromises their mechanical properties [[19], [20], [21], [22]]. This study focused on the elimination of macro-defects, such as porosity, lack of fusion, incomplete penetration and unmelted powders, which distinguishes them from micro-defects such as vacancies, dislocations, grain boundaries and secondary phases, etc. Large-sized fusion defects cause a severe reduction in mechanical strength. Smaller defects, such as pores and cracks, lead to the initiation of fatigue cracking and rapidly accelerate the cracking process [23]. The issue of internal macro-defects must be addressed to expand the application of the PBF-EB technology. The main studies for controlling internal macro-defects are online monitoring of defects, remelting and hot isostatic pressing (HIP). The literatures [24,25] report the use of infrared imaging or other imaging techniques to identify defects, but the monitoring of smaller sized defects is still not adequate. And in some cases remelting does not reduce the internal macro-defects of the part, but instead causes coarsening of the macrostructure and volatilization of some metal elements [23]. The HIP treatment does not completely eliminate the internal macro-defects, the original defect location may still act as a point of origin of the crack, and the subsequent treatment will consume more time and economic costs [23]. Therefore, optimizing suitable printing parameters to avoid internal macro-defects in printed parts at source is of great industrial value and research significance, and is an urgent issue in PBF-EB related technology.

There are two causes of internal macro-defects in the AM process: gas pores trapped in the virgin powder and the inappropriate printing parameters [7,23]. Gui et al. [26] classify internal macro-defects during PBF-EB process according to their shape, such as spherical defects, elongated shape defects, flat shape defects and other irregular shape defects. Of these, spherical defects mainly originate from raw material powders. Other shape defects mainly originate from lack of fusion or unmelted powders caused by unsuitable printing parameters, etc. The PBF-EB process requires powders with good flowability, and spherical powders are typically chosen as raw materials. The prevalent techniques for the fabrication of pre-alloyed powders are gas atomization (GA), plasma atomization (PA), and the plasma rotating electrode process (PREP) [27,28]. These methods yield powders with different characteristics that affect the subsequent fabrication. The selection of a suitable powder for PBF-EB is particularly important to produce Ti–6Al–4V alloys without internal macro-defects. The need to optimize several printing parameters such as beam current, scan speed, line offset, and focus offset make it difficult to eliminate internal macro-defects that occur during printing [23]. Most of the studies [11,12,22,[29], [30], [31], [32], [33]] on the optimization of AM processes for Ti–6Al–4V alloys have focused on samples with a limited set of parameters (e.g., power–scan speed) and do not allow for the guidance and development of unknown process windows for macro-defect-free samples. In addition, process optimization remains a time-consuming problem, with the traditional ‘trial and error’ method demanding considerable time and economic costs. The development of a simple and efficient method to predict the processing window for alloys without internal macro-defects is a key issue. In recent years, machine learning techniques have increasingly been used in the field of additive manufacturing and materials development [[34], [35], [36], [37]]. Aoyagi et al. [38] recently proposed a novel and efficient method based on a support vector machine (SVM) to optimize the two-dimensional process parameters (current and scan speed) and obtain PBF-EB-processed CoCr alloys without internal macro-defects. The method is one of the potential approaches toward effective optimization of more than two process parameters and makes it possible for the machine learning techniques to accelerate the development of alloys without internal macro-defects.

Herein, we focus on the elimination of internal macro-defects, such as pores, lack of fusion, etc., caused by raw powders and printing parameters. The Ti–6Al–4V powders produced by three different methods were compared, and the powder with the best sphericity, flowability, and minimal porosity was selected as the feedstock for subsequent printing. The relationship between the surface roughness and internal macro-defects in the Ti–6Al–4V components was also investigated. The combination of SVM and surface roughness indices (Sdr) predicted a wider four-dimensional processing window for obtaining Ti–6Al–4V alloys without internal macro-defects. Finally, we investigated the tensile properties of Ti–6Al–4V alloys at room temperature with different printing parameters, as well as the corresponding microstructures and fracture types.

Section snippets

Starting materials

Three types of Ti–6Al–4V alloy powders, produced by GA, PA, and PREP, were compared. The particle size distribution of the powders was determined using a laser particle size analyzer (LS230, Beckman Coulter, USA), and the flowability was measured using a Hall flowmeter (JIS-Z2502, Tsutsui Scientific Instruments Co., Ltd., Japan), according to the ASTM B213 standard. The powder morphology and internal macro-defects were determined using scanning electron microscopy (SEM, JEOL JCM-6000) and X-ray 

Comparison of the characteristics of GA, PA, and PREP Ti–6Al–4V powders

The particle size distributions (PSDs) and flowability of the three types of Ti–6Al–4V alloy powders produced by GA, PA, and PREP are shown in Fig. 2. Although the average particle sizes are similar (89.4 μm for GA, 82.5 μm for PA, and 86.1μm for PREP), the particle size range is different for the three types of powder (6.2–174.8 μm for GA, 27.3–139.2 μm for PA, and 39.4–133.9 μm for PREP). The flowability of the GA, PA, and PREP powders was 30.25 ± 0.98, 26.54 ± 0.37, and 25.03 ± 0.22 (s/50

Conclusions

The characteristics of the three types of Ti–6Al–4V alloy powders produced via GA, PA, and PREP were compared. The PREP powder with the best sphericity, flowability, and low porosity was found to be the most favorable powder for subsequent printing of Ti–6Al–4V alloys without internal macro-defects. The quantitative criterion of Sdr <0.015 for even surfaces was also found to be applicable to Ti–6Al–4V alloys. The process maps of Ti–6Al–4V alloys include two regions, high beam current/scan speed 

Uncited references

[55]; [56]; [57]; [58]; [59]; [60]; [61]; [62]; [63]; [64]; [65].

CRediT authorship contribution statement

Yunwei Gui: Writing – original draft, Visualization, Validation, Investigation. Kenta Aoyagi: Writing – review & editing, Supervision, Resources, Methodology, Funding acquisition, Conceptualization. Akihiko Chiba: Supervision, Funding acquisition.

Declaration of competing interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Acknowledgments

This study was based on the results obtained from project JPNP19007, commissioned by the New Energy and Industrial Technology Development Organization (NEDO). This work was also supported by JSPS KAKENHI (Proposal No. 21K03801) and the Inter-University Cooperative Research Program (Proposal nos. 18G0418, 19G0411, and 20G0418) of the Cooperative Research and Development Center for Advanced Materials, Institute for Materials Research, Tohoku University. It was also supported by the Council for

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Sketch of approach channel and spillway of the Kamal-Saleh dam

CFD modeling of flow pattern in spillway’s approach channel

Sustainable Water Resources Management volume 1, pages245–251 (2015)Cite this article

Abstract

Analysis of behavior and hydraulic characteristics of flow over the dam spillway is a complicated task that takes lots of money and time in water engineering projects planning. To model those hydraulic characteristics, several methods such as physical and numerical methods can be used. Nowadays, by utilizing new methods in computational fluid dynamics (CFD) and by the development of fast computers, the numerical methods have become accessible for use in the analysis of such sophisticated flows. The CFD softwares have the capability to analyze two- and three-dimensional flow fields. In this paper, the flow pattern at the guide wall of the Kamal-Saleh dam was modeled by Flow 3D. The results show that the current geometry of the left wall causes instability in the flow pattern and making secondary and vortex flow at beginning approach channel. This shape of guide wall reduced the performance of weir to remove the peak flood discharge.

댐 여수로 흐름의 거동 및 수리학적 특성 분석은 물 공학 프로젝트 계획에 많은 비용과 시간이 소요되는 복잡한 작업입니다. 이러한 수력학적 특성을 모델링하기 위해 물리적, 수치적 방법과 같은 여러 가지 방법을 사용할 수 있습니다. 요즘에는 전산유체역학(CFD)의 새로운 방법을 활용하고 빠른 컴퓨터의 개발로 이러한 정교한 흐름의 해석에 수치 방법을 사용할 수 있게 되었습니다. CFD 소프트웨어에는 2차원 및 3차원 유동장을 분석하는 기능이 있습니다. 본 논문에서는 Kamal-Saleh 댐 유도벽의 흐름 패턴을 Flow 3D로 모델링하였다. 결과는 왼쪽 벽의 현재 형상이 흐름 패턴의 불안정성을 유발하고 시작 접근 채널에서 2차 및 와류 흐름을 만드는 것을 보여줍니다. 이러한 형태의 안내벽은 첨두방류량을 제거하기 위해 둑의 성능을 저하시켰다.

Introduction

Spillways are one of the main structures used in the dam projects. Design of the spillway in all types of dams, specifically earthen dams is important because the inability of the spillway to remove probable maximum flood (PMF) discharge may cause overflow of water which ultimately leads to destruction of the dam (Das and Saikia et al. 2009; E 2013 and Novak et al. 2007). So study on the hydraulic characteristics of this structure is important. Hydraulic properties of spillway including flow pattern at the entrance of the guide walls and along the chute. Moreover, estimating the values of velocity and pressure parameters of flow along the chute is very important (Chanson 2004; Chatila and Tabbara 2004). The purpose of the study on the flow pattern is the effect of wall geometry on the creation transverse waves, flow instability, rotating and reciprocating flow through the inlet of spillway and its chute (Parsaie and Haghiabi 2015ab; Parsaie et al. 2015; Wang and Jiang 2010). The purpose of study on the values of velocity and pressure is to calculate the potential of the structure to occurrence of phenomena such as cavitation (Fattor and Bacchiega 2009; Ma et al. 2010). Sometimes, it can be seen that the spillway design parameters of pressure and velocity are very suitable, but geometry is considered not suitable for conducting walls causing unstable flow pattern over the spillway, rotating flows at the beginning of the spillway and its design reduced the flood discharge capacity (Fattor and Bacchiega 2009). Study on spillway is usually conducted using physical models (Su et al. 2009; Suprapto 2013; Wang and Chen 2009; Wang and Jiang 2010). But recently, with advances in the field of computational fluid dynamics (CFD), study on hydraulic characteristics of this structure has been done with these techniques (Chatila and Tabbara 2004; Zhenwei et al. 2012). Using the CFD as a powerful technique for modeling the hydraulic structures can reduce the time and cost of experiments (Tabbara et al. 2005). In CFD field, the Navier–Stokes equation is solved by powerful numerical methods such as finite element method and finite volumes (Kim and Park 2005; Zhenwei et al. 2012). In order to obtain closed-form Navier–Stokes equations turbulence models, such k − ε and Re-Normalisation Group (RNG) models have been presented. To use the technique of computational fluid dynamics, software packages such as Fluent and Flow 3D, etc., are provided. Recently, these two software packages have been widely used in hydraulic engineering because the performance and their accuracy are very suitable (Gessler 2005; Kim 2007; Kim et al. 2012; Milési and Causse 2014; Montagna et al. 2011). In this paper, to assess the flow pattern at Kamal-Saleh guide wall, numerical method has been used. All the stages of numerical modeling were conducted in the Flow 3D software.

Materials and methods

Firstly, a three-dimensional model was constructed according to two-dimensional map that was prepared for designing the spillway. Then a small model was prepared with scale of 1:80 and entered into the Flow 3D software; all stages of the model construction was conducted in AutoCAD 3D. Flow 3D software numerically solved the Navier–Stokes equation by finite volume method. Below is a brief reference on the equations that used in the software. Figure 1 shows the 3D sketch of Kamal-Saleh spillway and Fig. 2 shows the uploading file of the Kamal-Saleh spillway in Flow 3D software.

figure 1
Fig. 1
figure 2
Fig. 2

Review of the governing equations in software Flow 3D

Continuity equation at three-dimensional Cartesian coordinates is given as Eq (1).

vf∂ρ∂t+∂∂x(uAx)+∂∂x(vAy)+∂∂x(wAz)=PSORρ,vf∂ρ∂t+∂∂x(uAx)+∂∂x(vAy)+∂∂x(wAz)=PSORρ,

(1)

where uvz are velocity component in the x, y, z direction; A xA yA z cross-sectional area of the flow; ρ fluid density; PSOR the source term; v f is the volume fraction of the fluid and three-dimensional momentum equations given in Eq (2).

∂u∂t+1vf(uAx∂u∂x+vAy∂u∂y+wAz∂u∂z)=−1ρ∂P∂x+Gx+fx∂v∂t+1vf(uAx∂v∂x+vAy∂v∂y+wAz∂v∂z)=−1ρ∂P∂y+Gy+fy∂w∂t+1vf(uAx∂w∂x+vAy∂w∂y+wAz∂w∂z)=−1ρ∂P∂y+Gz+fz,∂u∂t+1vf(uAx∂u∂x+vAy∂u∂y+wAz∂u∂z)=−1ρ∂P∂x+Gx+fx∂v∂t+1vf(uAx∂v∂x+vAy∂v∂y+wAz∂v∂z)=−1ρ∂P∂y+Gy+fy∂w∂t+1vf(uAx∂w∂x+vAy∂w∂y+wAz∂w∂z)=−1ρ∂P∂y+Gz+fz,

(2)

where P is the fluid pressure; G xG yG z the acceleration created by body fluids; f xf yf z viscosity acceleration in three dimensions and v f is related to the volume of fluid, defined by Eq. (3). For modeling of free surface profile the VOF technique based on the volume fraction of the computational cells has been used. Since the volume fraction F represents the amount of fluid in each cell, it takes value between 0 and 1.

∂F∂t+1vf[∂∂x(FAxu)+∂∂y(FAyv)+∂∂y(FAzw)]=0∂F∂t+1vf[∂∂x(FAxu)+∂∂y(FAyv)+∂∂y(FAzw)]=0

(3)

Turbulence models

Flow 3D offers five types of turbulence models: Prantl mixing length, k − ε equation, RNG models, Large eddy simulation model. Turbulence models that have been proposed recently are based on Reynolds-averaged Navier–Stokes equations. This approach involves statistical methods to extract an averaged equation related to the turbulence quantities.

Steps of solving a problem in Flow 3D software

(1) Preparing the 3D model of spillway by AutoCAD software. (2) Uploading the file of 3D model in Flow 3D software and defining the problem in the software and checking the final mesh. (3) Choosing the basic equations that should be solved. (4) Defining the characteristics of fluid. (5) Defining the boundary conditions; it is notable that this software has a wide range of boundary conditions. (6) Initializing the flow field. (7) Adjusting the output. (8) Adjusting the control parameters, choice of the calculation method and solution formula. (9) Start of calculation. Figure 1 shows the 3D model of the Kamal-Saleh spillway; in this figure, geometry of the left and right guide wall is shown.

Figure 2 shows the uploading of the 3D spillway dam in Flow 3D software. Moreover, in this figure the considered boundary condition in software is shown. At the entrance and end of spillway, the flow rate or fluid elevation and outflow was considered as BC. The bottom of spillway was considered as wall and left and right as symmetry.

Model calibration

Calibration of the Flow 3D for modeling the effect of geometry of guide wall on the flow pattern is included for comparing the results of Flow 3D with measured water surface profile. Calibration the Flow 3D software could be conducted in two ways: first, changing the value of upstream boundary conditions is continued until the results of water surface profile of the Flow 3D along the spillway successfully covered the measurement water surface profile; second is the assessment the mesh sensitivity. Analyzing the size of mesh is a trial-and-error process where the size of mesh is evaluated form the largest to the smallest. With fining the size of mesh the accuracy of model is increased; whereas, the cost of computation is increased. In this research, the value of upstream boundary condition was adjusted with measured data during the experimental studies on the scaled model and the mesh size was equal to 1 × 1 × 1 cm3.

Results and discussion

The behavior of water in spillway is strongly affected by the flow pattern at the entrance of the spillway, the flow pattern formation at the entrance is affected by the guide wall, and choice of an optimized form for the guide wall has a great effect on rising the ability of spillway for easy passing the PMF, so any nonuniformity in flow in the approach channel can cause reduction of spillway capacity, reduction in discharge coefficient of spillway, and even probability of cavitation. Optimizing the flow guiding walls (in terms of length, angle and radius) can cause the loss of turbulence and flow disturbances on spillway. For this purpose, initially geometry proposed for model for the discharge of spillway dam, Kamal-Saleh, 80, 100, and 120 (L/s) were surveyed. These discharges of flow were considered with regard to the flood return period, 5, 100 and 1000 years. Geometric properties of the conducting guidance wall are given in Table 1.Table 1 Characteristics and dimensions of the guidance walls tested

Full size table

Results of the CFD simulation for passing the flow rate 80 (L/s) are shown in Fig. 3. Figure 3 shows the secondary flow and vortex at the left guide wall.

figure 3
Fig. 3

For giving more information about flow pattern at the left and right guide wall, Fig. 4 shows the flow pattern at the right side guide wall and Fig. 5 shows the flow pattern at the left side guide wall.

figure 4
Fig. 4
figure 5
Fig. 5

With regard to Figs. 4 and 5 and observing the streamlines, at discharge equal to 80 (L/s), the right wall has suitable performance but the left wall has no suitable performance and the left wall of the geometric design creates a secondary and circular flow, and vortex motion in the beginning of the entrance of spillway that creates cross waves at the beginning of spillway. By increasing the flow rate (Q = 100 L/s), at the inlet spillway secondary flows and vortex were removed, but the streamline is severely distorted. Results of the guide wall performances at the Q = 100 (L/s) are shown in Fig. 6.

figure 6
Fig. 6

Also more information about the performance of each guide wall can be derived from Figs. 7 and 8. These figures uphold that the secondary and vortex flows were removed, but the streamlines were fully diverted specifically near the left side guide wall.

figure 7
Fig. 7
figure 8
Fig. 8

As mentioned in the past, these secondary and vortex flows and diversion in streamline cause nonuniformity and create cross wave through the spillway. Figure 9 shows the cross waves at the crest of the spillway.

figure 9
Fig. 9

The performance of guide walls at the Q = 120 (L/s) also was assessed. The result of simulation is shown in Fig. 10. Figures 11 and 12 show a more clear view of the streamlines near to right and left side guide wall, respectively. As seen in Fig. 12, the left side wall still causes vortex flow and creation of and diversion in streamline.

figure 10
Fig. 10
figure 11
Fig. 11
figure 12
Fig. 12

The results of the affected left side guide wall shape on the cross wave creation are shown in Fig. 13. As seen from Fig. 3, the left side guide wall also causes cross wave at the spillway crest.

figure 13
Fig. 13

As can be seen clearly in Figs. 9 and 13, by moving from the left side to the right side of the spillway, the cross waves and the nonuniformity in flow is removed. By reviewing Figs. 9 and 13, it is found that the right side guide wall removes the cross waves and nonuniformity. With this point as aim, a geometry similar to the right side guide wall was considered instead of the left side guide wall. The result of simulation for Q = 120 (L/s) is shown in Fig. 14. As seen from this figure, the proposed geometry for the left side wall has suitable performance smoothly passing the flow through the approach channel and spillway.

figure 14
Fig. 14

More information about the proposed shape for the left guide wall is shown in Fig. 15. As seen from this figure, this shape has suitable performance for removing the cross waves and vortex flows.

figure 15
Fig. 15

Figure 16 shows the cross section of flow at the crest of spillway. As seen in this figure, the proposed shape for the left side guide wall is suitable for removing the cross waves and secondary flows.

figure 16
Fig. 16

Conclusion

Analysis of behavior and hydraulic properties of flow over the spillway dam is a complicated task which is cost and time intensive. Several techniques suitable to the purposes of study have been undertaken in this research. Physical modeling, usage of expert experience, usage of mathematical models on simulation flow in one-dimensional, two-dimensional and three-dimensional techniques, are some of the techniques utilized to study this phenomenon. The results of the modeling show that the CFD technique is a suitable tool for simulating the flow pattern in the guide wall. Using this tools helps the designer for developing the optimal shape for hydraulic structure which the flow pattern through them are important.

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  1. Department of Water Engineering, Lorestan University, Khorram Abad, IranAbbas Parsaie, Amir Hamzeh Haghiabi & Amir Moradinejad

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Correspondence to Abbas Parsaie.

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Parsaie, A., Haghiabi, A.H. & Moradinejad, A. CFD modeling of flow pattern in spillway’s approach channel. Sustain. Water Resour. Manag. 1, 245–251 (2015). https://doi.org/10.1007/s40899-015-0020-9

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  • Received28 April 2015
  • Accepted28 August 2015
  • Published15 September 2015
  • Issue DateSeptember 2015
  • DOIhttps://doi.org/10.1007/s40899-015-0020-9

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Keywords

  • Approach channel
  • Kamal-Saleh dam
  • Guide wall
  • Flow pattern
  • Numerical modeling
  • Flow 3D software
    Figure 10. Flow distribution at the approach channel in PMF based on revised plan design. A. Hydarulic model test; B. Numerical simulation; C. Section view.

    Improvement of hydraulic stability for spillway using CFD model

    Hydraulic model test was used to analyze the rapidly varied flow on the spillway. But, it has some shortcomings such as error of scale effect and expensive costs. Recently, through the development of three dimensional computational fluid dynamics (CFD), rapidly varied flow and turbulence can be simulated. In this study, the applicability of CFD model to simulate flow on the spillway was reviewed. The Karian dam in Indonesia was selected as the study area. The FLOW-3d model, which is well known to simulate a flow having a free surface, was used to analyze flow. The flow stability in approach channel was investigated with the initial plan design, and the results showed that the flow in approach channel is unstable in the initial plan design. To improve flow stability in the spillway, therefore, the revised plan design was formulated. The appropriateness of the revised design was examined by a numerical modeling. The results showed that the flow in spillway is stable in the revised design.

    여수로의 급격하게 변화하는 흐름을 분석하기 위해 수리학적 모델 테스트를 사용했습니다. 그러나 스케일 효과의 오차와 고가의 비용 등의 단점이 있다. 최근에는 3차원 전산유체역학(CFD)의 발달로 급변하는 유동과 난류를 모사할 수 있다. 본 연구에서는 여수로의 흐름을 시뮬레이션하기 위한 CFD 모델의 적용 가능성을 검토했습니다. 인도네시아의 Karian 댐이 연구 지역으로 선정되었습니다. 자유표면을 갖는 유동을 모의하는 것으로 잘 알려진 FLOW-3d 모델을 유동해석에 사용하였다. 접근수로의 흐름 안정성은 초기 계획설계와 함께 조사한 결과 초기 계획설계에서 접근수로의 흐름이 불안정한 것으로 나타났다. 따라서 방수로의 흐름 안정성을 향상시키기 위해 수정된 계획 설계가 공식화되었습니다. 수정된 설계의 적합성을 수치모델링을 통해 검토하였다. 결과는 수정된 설계에서 여수로의 흐름이 안정적이라는 것을 보여주었습니다.

    Key words

    Spillway, FLOW-3D, approach channel, flow stability, numerical modeling, hydraulic model test.

    Figure 6. Two dimensional flow velocity distribution at the
approach channel (Flow velocity distribution at depth EL. 68.12 m).
    Figure 6. Two dimensional flow velocity distribution at the approach channel (Flow velocity distribution at depth EL. 68.12 m).
    Figure 7. Flow distribution at the approach channel in PMF.
A. Hydraulic model test; B. Numerial simulatio
C. Cross section view.
    Figure 7. Flow distribution at the approach channel in PMF. A. Hydraulic model test; B. Numerial simulatio C. Cross section view.
    Figure 8. Revised approach channel section.
A. Initial plan design; B. Revised plan design.
    Figure 8. Revised approach channel section. A. Initial plan design; B. Revised plan design.
    Figure 9. Two dimensional flow velocity distribution at the approach channel
based on revised plan design (Flow velocity distribution at depth EL. 68.12 m).
    Figure 9. Two dimensional flow velocity distribution at the approach channel based on revised plan design (Flow velocity distribution at depth EL. 68.12 m).
    Figure 10. Flow distribution at the approach channel in PMF based on revised plan design.
A. Hydarulic model test; B. Numerical simulation; C. Section view.
    Figure 10. Flow distribution at the approach channel in PMF based on revised plan design. A. Hydarulic model test; B. Numerical simulation; C. Section view.

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    Numerical analysis of energy dissipator options using computational fluid dynamics modeling — a case study of Mirani Dam

    전산 유체 역학 모델링을 사용한 에너지 소산자 옵션의 수치적 해석 — Mirani 댐의 사례 연구

    Arabian Journal of Geosciences volume 15, Article number: 1614 (2022) Cite this article

    Abstract

    이 연구에서 FLOW 3D 전산 유체 역학(CFD) 소프트웨어를 사용하여 파키스탄 Mirani 댐 방수로에 대한 에너지 소산 옵션으로 미국 매립지(USBR) 유형 II 및 USBR 유형 III 유역의 성능을 추정했습니다. 3D Reynolds 평균 Navier-Stokes 방정식이 해결되었으며, 여기에는 여수로 위의 자유 표면 흐름을 캡처하기 위해 공기 유입, 밀도 평가 및 드리프트-플럭스에 대한 하위 그리드 모델이 포함되었습니다. 본 연구에서는 5가지 모델을 고려하였다. 첫 번째 모델에는 길이가 39.5m인 USBR 유형 II 정수기가 있습니다. 두 번째 모델에는 길이가 44.2m인 USBR 유형 II 정수기가 있습니다. 3번째와 4 번째모델에는 길이가 각각 48.8m인 USBR 유형 II 정수조와 39.5m의 USBR 유형 III 정수조가 있습니다. 다섯 번째 모델은 네 번째 모델과 동일하지만 마찰 및 슈트 블록 높이가 0.3m 증가했습니다. 최상의 FLOW 3D 모델 조건을 설정하기 위해 메쉬 민감도 분석을 수행했으며 메쉬 크기 0.9m에서 최소 오차를 산출했습니다. 세 가지 경계 조건 세트가 테스트되었으며 최소 오류를 제공하는 세트가 사용되었습니다. 수치적 검증은 USBR 유형 II( L = 48.8m), USBR 유형 III( L = 35.5m) 및 USBR 유형 III 의 물리적 모델 에너지 소산을 0.3m 블록 단위로 비교하여 수행되었습니다( L= 35.5m). 통계 분석 결과 평균 오차는 2.5%, RMSE(제곱 평균 제곱근 오차) 지수는 3% 미만이었습니다. 수리학적 및 경제성 분석을 바탕으로 4 번째 모델이 최적화된 에너지 소산기로 밝혀졌습니다. 흡수된 에너지 백분율 측면에서 물리적 모델과 수치적 모델 간의 최대 차이는 5% 미만인 것으로 나타났습니다.

    In this study, the FLOW 3D computational fluid dynamics (CFD) software was used to estimate the performance of the United States Bureau of Reclamation (USBR) type II and USBR type III stilling basins as energy dissipation options for the Mirani Dam spillway, Pakistan. The 3D Reynolds-averaged Navier–Stokes equations were solved, which included sub-grid models for air entrainment, density evaluation, and drift–flux, to capture free-surface flow over the spillway. Five models were considered in this research. The first model has a USBR type II stilling basin with a length of 39.5 m. The second model has a USBR type II stilling basin with a length of 44.2 m. The 3rd and 4th models have a USBR type II stilling basin with a length of 48.8 m and a 39.5 m USBR type III stilling basin, respectively. The fifth model is identical to the fourth, but the friction and chute block heights have been increased by 0.3 m. To set up the best FLOW 3D model conditions, mesh sensitivity analysis was performed, which yielded a minimum error at a mesh size of 0.9 m. Three sets of boundary conditions were tested and the set that gave the minimum error was employed. Numerical validation was done by comparing the physical model energy dissipation of USBR type II (L = 48.8 m), USBR type III (L =35.5 m), and USBR type III with 0.3-m increments in blocks (L = 35.5 m). The statistical analysis gave an average error of 2.5% and a RMSE (root mean square error) index of less than 3%. Based on hydraulics and economic analysis, the 4th model was found to be an optimized energy dissipator. The maximum difference between the physical and numerical models in terms of percentage energy absorbed was found to be less than 5%.

    Keywords

    • Numerical modeling
    • Spillway
    • Hydraulic jump
    • Energy dissipation
    • FLOW 3D

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    다공층에 대한 돌발 댐 붕괴의 3차원 유동 수치해석 시뮬레이션

    A. Safarzadeh1*, P. Mohsenzadeh2, S. Abbasi3
    1 Professor of Civil Eng., Water Engineering and Mineral Waters Research Center, Univ. of Mohaghegh Ardabili,Ardabil, Iran
    2 M.Sc., Graduated of Civil-Hydraulic Structures Eng., Faculty of Eng., Univ. of Mohaghegh Ardabili, Ardabil, Iran
    3 M.Sc., Graduated of Civil -Hydraulic Structures Eng., Faculty of Eng., Univ. of Mohaghegh Ardabili, Ardabil, Iran Safarzadeh@uma.ac.ir

    Highlights

    유체 이동에 의해 생성된 RBF는 Ls-Dyna에서 Fluent, ICFD ALE 및 SPH 방법으로 시뮬레이션되었습니다.
    RBF의 과예측은 유체가 메인 도메인에서 고속으로 분리될 때 발생합니다.
    이 과잉 예측은 요소 크기, 시간 단계 크기 및 유체 모델에 따라 다릅니다.
    유체 성능을 검증하려면 최대 RBF보다 임펄스가 권장됩니다.

    Abstract

    Dam break is a very important problem due to its effects on economy, security, human casualties and environmental consequences. In this study, 3D flow due to dam break over the porous substrate is numerically simulated and the effect of porosity, permeability and thickness of the porous bed and the water depth in the porous substrate are investigated. Classic models of dam break over a rigid bed and water infiltration through porous media were studied and results of the numerical simulations are compared with existing laboratory data. Validation of the results is performed by comparing the water surface profiles and wave front position with dam break on rigid and porous bed. Results showed that, due to the effect of dynamic wave in the initial stage of dam break, a local peak occurs in the flood hydrograph. The presence of porous bed reduces the acceleration of the flood wave relative to the flow over the solid bed and it decreases with the increase of the permeability of the bed. By increasing the permeability of the bed, the slope of the ascending limb of the flood hydrograph and the peak discharge drops. Furthermore, if the depth and permeability of the bed is such that the intrusive flow reaches the rigid substrate under the porous bed, saturation of the porous bed, results in a sharp increase in the slope of the flood hydrograph. The maximum values of the peak discharge at the end of the channel with porous bed occurred in saturated porous bed conditions.

    댐 붕괴는 경제, 보안, 인명 피해 및 환경적 영향으로 인해 매우 중요한 문제입니다. 본 연구에서는 다공성 기재에 대한 댐 파괴로 인한 3차원 유동을 수치적으로 시뮬레이션하고 다공성 기재의 다공성, 투과도 및 다공성 층의 두께 및 수심의 영향을 조사합니다. 단단한 바닥에 대한 댐 파괴 및 다공성 매체를 통한 물 침투의 고전 모델을 연구하고 수치 시뮬레이션 결과를 기존 실험실 데이터와 비교합니다. 결과 검증은 강체 및 다공성 베드에서 댐 파단과 수면 프로파일 및 파면 위치를 비교하여 수행됩니다. 그 결과 댐파괴 초기의 동적파동의 영향으로 홍수수문곡선에서 국부첨두가 발생하는 것으로 나타났다. 다공성 베드의 존재는 고체 베드 위의 유동에 대한 홍수파의 가속을 감소시키고 베드의 투과성이 증가함에 따라 감소합니다. 베드의 투수성을 증가시켜 홍수 수문곡선의 오름차순 경사와 첨두방류량이 감소한다. 더욱이, 만약 층의 깊이와 투과성이 관입 유동이 다공성 층 아래의 단단한 기질에 도달하는 정도라면, 다공성 층의 포화는 홍수 수문곡선의 기울기의 급격한 증가를 초래합니다. 다공층이 있는 채널의 끝단에서 최대 방전 피크값은 포화 다공층 조건에서 발생하였다.

    Keywords

    Keywords: Dams Break, 3D modeling, Porous Bed, Permeability, Flood wave

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    Flow Field in a Sloped Channel with Damaged and Undamaged Piers: Numerical and Experimental Studies

    Flow Field in a Sloped Channel with Damaged and Undamaged Piers: Numerical and Experimental Studies

    Ehsan OveiciOmid Tayari & Navid Jalalkamali
    KSCE Journal of Civil Engineering volume 25, pages4240–4251 (2021)Cite this article

    Abstract

    본 논문은 경사가 완만한 수로에서 손상되거나 손상되지 않은 교각 주변의 유동 패턴을 분석했습니다. 실험은 길이가 12m이고 기울기가 0.008인 직선 수로에서 수행되었습니다. Acoustic Doppler Velocimeter(ADV)를 이용하여 3차원 유속 데이터를 수집하였고, 그 결과를 PIV(Particle Image Velocimetry) 데이터와 분석하여 비교하였습니다.

    다중 블록 옵션이 있는 취수구의 퇴적물 시뮬레이션(SSIIM)은 이 연구에서 흐름의 수치 시뮬레이션을 위해 통합되었습니다. 일반적으로 비교에서 얻은 결과는 수치 데이터와 실험 데이터 간의 적절한 일치를 나타냅니다. 결과는 모든 경우에 수로 입구에서 2m 거리에서 기복적 수압 점프가 발생했음을 보여주었습니다.

    경사진 수로의 최대 베드 전단응력은 2개의 손상 및 손상되지 않은 교각을 설치하기 위한 수평 수로의 12배였습니다. 이와 같은 경사수로 교각의 위치에 따라 상류측 수위는 수평수로의 유사한 조건에 비해 72.5% 감소한 반면, 이 감소량은 경사면에서 다른 경우에 비해 8.3% 감소하였다. 채널 또한 두 교각이 있는 경우 최대 Froude 수는 수평 수로의 5.7배였습니다.

    This paper analyzed the flow pattern around damaged and undamaged bridge piers in a channel with a mild slope. The experiments were carried out on a straight channel with a length of 12 meters and a slope of 0.008. Acoustic Doppler velocimeter (ADV) was employed to collect three-dimensional flow velocity data, and the results were analyzed and compared with particle image velocimetry (PIV) data. Sediment Simulation in Intakes with Multiblock option (SSIIM) was incorporated for the numerical simulation of the flow in this study. Generally, the results obtained from the comparisons referred to the appropriate agreement between the numerical and the experimental data. The results showed that an undular hydraulic jump occurred at a distance of two meters from the channel entrance in every case; the maximum bed shear stress in the sloped channel was 12 times that in a horizontal channel for installing two damaged and undamaged piers. With this position of the piers in the sloped channel, the upstream water level underwent a 72.5% reduction compared to similar conditions in a horizontal channel, while the amount of this water level decrease was equal to 8.3% compared to the other cases in a sloped channel. In addition, with the presence of both piers, the maximum Froude number was 5.7 times that in a horizontal channel.

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    하류하천의 영향 최소화를 위한 보조 여수로 최적 활용방안 검토

    The Optimal Operation on Auxiliary Spillway to Minimize the Flood Damage in Downstream River with Various Outflow Conditions

    하류하천의 영향 최소화를 위한 보조 여수로 최적 활용방안 검토

    Hyung Ju Yoo1, Sung Sik Joo2, Beom Jae Kwon3, Seung Oh Lee4*

    유 형주1, 주 성식2, 권 범재3, 이 승오4*

    1Ph.D Student, Dept. of Civil & Environmental Engineering, Hongik University
    2Director, Water Resources & Environment Department, HECOREA
    3Director, Water Resources Department, ISAN
    4Professor, Dept. of Civil & Environmental Engineering, Hongik University

    1홍익대학교 건설환경공학과 박사과정
    2㈜헥코리아 수자원환경사업부 이사
    3㈜이산 수자원부 이사
    4홍익대학교 건설환경공학과 교수

    ABSTRACT

    최근 기후변화로 인해 강우강도 및 빈도의 증가에 따른 집중호우의 영향 및 기존 여수로의 노후화에 대비하여 홍수 시 하류 하천의 영향을 최소화할 수 있는 보조 여수로 활용방안 구축이 필요한 실정이다. 이를 위해, 수리모형 실험 및 수치모형 실험을 통하여 보조 여수로 운영에 따른 흐름특성 변화 검토에 관한 연구가 많이 진행되어 왔다. 그러나 대부분의 연구는 여수로에서의 흐름특성 및 기능성에 대한 검토를 수행하였을 뿐 보조 여수로의 활용방안에 따른 하류하천 영향 검토 및 호안 안정성 검토에 관한 연구는 미비한 실정이다. 이에 본 연구에서는 기존 여수로 및 보조 여수로 방류 조건에 따른 하류영향 분석 및 호안 안정성 측면에서 최적 방류 시나리오 검토를 3차원 수치모형인 FLOW-3D를 사용하여 검토하였다. 또한 FLOW-3D 수치모의 수행을 통한 유속, 수위 결과와 소류력 산정 결과를 호안 설계허용 기준과 비교하였다. 수문 완전 개도 조건으로 가정하고 계획홍수량 유입 시 다양한 보조 여수로 활용방안에 대하여 수치모의를 수행한 결과, 보조 여수로 단독 운영 시 기존 여수로 단독운영에 비하여 최대유속 및 최대 수위의 감소효과를 확인하였다. 다만 계획홍수량의 45% 이하 방류 조건에서 대안부의 호안 안정성을 확보하였고 해당 방류량 초과 경우에는 처오름 현상이 발생하여 월류에 대한 위험성 증가를 확인하였다. 따라서 기존 여수로와의 동시 운영 방안 도출이 중요하다고 판단하였다. 여수로의 배분 비율 및 총 허용 방류량에 대하여 검토한 결과 보조 여수로의 방류량이 기존 여수로의 방류량보다 큰 경우 하류하천의 흐름이 중심으로 집중되어 대안부의 유속 저감 및 수위 감소를 확인하였고, 계획 홍수량의 77% 이하의 조건에서 호안의 허용 유속 및 허용 소류력 조건을 만족하였다. 이를 통하여 본 연구에서 제안한 보조 여수로 활용방안으로는 기존 여수로와 동시 운영 시 총 방류량에 대하여 보조 여수로의 배분량이 기존 여수로의 배분량보다 크게 설정하는 것이 하류하천의 영향을 최소화 할 수 있는 것으로 나타났다. 그러나 본 연구는 여수로 방류에 따른 대안부에서의 영향에 대해서만 검토하였고 수문 전면 개도 조건에서 검토하였다는 한계점은 분명히 있다. 이에 향후에는 다양한 수문 개도 조건 및 방류 시나리오를 적용 및 검토한다면 보다 효율적이고, 효과적인 보조 여수로 활용방안을 도출이 가능할 것으로 기대 된다.

    키워드 : 보조 여수로, FLOW-3D, 수치모의, 호안 안정성, 소류력

    1. 서 론

    최근 기후변화로 인한 집중호우의 영향으로 홍수 시 댐으로 유입되는 홍수량이 설계 홍수량보다 증가하여 댐 안정성 확보가 필요한 실정이다(Office for Government Policy Coordination, 2003). MOLIT & K-water(2004)에서는 기존댐의 수문학적 안정성 검토를 수행하였으며 이상홍수 발생 시 24개 댐에서 월류 등으로 인한 붕괴위험으로 댐 하류지역의 극심한 피해를 예상하여 보조여수로 신설 및 기존여수로 확장 등 치수능력 증대 기본계획을 수립하였고 이를 통하여 극한홍수 발생 시 홍수량 배제능력을 증대하여 기존댐의 안전성 확보 및 하류지역의 피해를 방지하고자 하였다. 여기서 보조 여수로는 기존 여수로와 동시 또는 별도 운영하는 여수로로써 비상상황 시 방류 기능을 포함하고 있고(K-water, 2021), 최근에는 기존 여수로의 노후화에 따라 보조여수로의 활용방안에 대한 관심이 증가하고 있다. 따라서 본 연구에서는 3차원 수치해석을 수행하여 기존 및 보조 여수로의 방류량 조합에 따른 하류 영향을 분석하고 하류 호안 안정성 측면에서 최적 방류 시나리오를 검토하고자 한다.

    기존의 댐 여수로 검토에 관한 연구는 주로 수리실험을 통하여 방류조건 별 흐름특성을 검토하였으나 최근에는 수치모형 실험결과가 수리모형실험과 비교하여 근사한 것을 확인하는 등 점차 수치모형실험을 수리모형실험의 대안으로 활용하고 있다(Jeon et al., 2006Kim, 2007Kim et al., 2008). 국내의 경우, Jeon et al.(2006)은 수리모형 실험과 수치모의를 이용하여 임하댐 바상여수로의 기본설계안을 도출하였고, Kim et al.(2008)은 가능최대홍수량 유입 시 비상여수로 방류에 따른 수리학적 안정성과 기능성을 3차원 수치모형인 FLOW-3D를 활용하여 검토하였다. 또한 Kim and Kim(2013)은 충주댐의 홍수조절 효과 검토 및 방류량 변화에 따른 상·하류의 수위 변화를 수치모형을 통하여 검토하였다. 국외의 경우 Zeng et al.(2017)은 3차원 수치모형인 Fluent를 활용한 여수로 방류에 따른 흐름특성 결과와 측정결과를 비교하여 수치모형 결과의 신뢰성을 검토하였다. Li et al.(2011)은 가능 최대 홍수량(Probable Maximum Flood, PMF)조건에서 기존 여수로와 신규 보조 여수로 유입부 주변의 흐름특성에 대하여 3차원 수치모형 Fluent를 활용하여 검토하였고, Lee et al.(2019)는 서로 근접해있는 기존 여수로와 보조여수로 동시 운영 시 방류능 검토를 수리모형 실험 및 수치모형 실험(FLOW-3D)을 통하여 수행하였으며 기존 여수로와 보조 여수로를 동시운영하게 되면 배수로 간섭으로 인하여 총 방류량이 7.6%까지 감소되어 댐의 방류능력이 감소하였음을 확인하였다.

    그러나 대부분의 여수로 검토에 대한 연구는 여수로 내에서의 흐름특성 및 기능성에 대한 검토를 수행하였고. 이에 기존 여수로와 보조 여수로 방류운영에 따른 하류하천의 흐름특성 변화 및 호안 안정성 평가에 관한 추가적인 검토가 필요한 실정이다. 따라서 본 연구에서는 기존 여수로 및 보조 여수로 방류 조건에 따른 하류하천의 흐름특성 및 호안 안정성분석을 3차원 수치모형인 FLOW-3D를 이용하여 검토하였다. 또한 다양한 방류 배분 비율 및 허용 방류량 조건 변화에 따른 하류하천의 흐름특성 및 소류력 분석결과를 호안 설계 허용유속 및 허용 소류력 기준과 비교하여 하류하천의 영향을 최소화 할 수 있는 최적의 보조 여수로 활용방안을 도출하고자 한다.

    2. 본 론

    2.1 이론적 배경

    2.1.1 3차원 수치모형의 기본이론

    FLOW-3D는 미국 Flow Science, Inc에서 개발한 범용 유체역학 프로그램(CFD, Computational Fluid Dynamics)으로 자유 수면을 갖는 흐름모의에 사용되는 3차원 수치해석 모형이다. 난류모형을 통해 난류 해석이 가능하고, 댐 방류에 따른 하류 하천의 흐름 해석에도 많이 사용되어 왔다(Flow Science, 2011). 본 연구에서는 FLOW-3D(version 12.0)을 이용하여 홍수 시 기존 여수로의 노후화에 대비하여 보조 여수로의 활용방안에 대한 검토를 하류하천의 호안 안정성 측면에서 검토하였다.

    2.1.2 유동해석의 지배방정식

    1) 연속 방정식(Continuity Equation)

    FLOW-3D는 비압축성 유체에 대하여 연속방정식을 사용하며, 밀도는 상수항으로 적용된다. 연속 방정식은 Eqs. (1)(2)와 같다.

    (1)

    ∇·v=0

    (2)

    ∂∂x(uAx)+∂∂y(vAy)+∂∂z(wAz)=RSORρ

    여기서, ρ는 유체 밀도(kg/m3), u, v, w는 x, y, z방향의 유속(m/s), Ax, Ay, Az는 각 방향의 요소면적(m2), RSOR는 질량 생성/소멸(mass source/sink)항을 의미한다.

    2) 운동량 방정식(Momentum Equation)

    각 방향 속도성분 u, v, w에 대한 운동방정식은 Navier-Stokes 방정식으로 다음 Eqs. (3)(4)(5)와 같다.

    (3)

    ∂u∂t+1VF(uAx∂u∂x+vAy∂v∂y+wAz∂w∂z)=-1ρ∂p∂x+Gx+fx-bx-RSORρVFu

    (4)

    ∂v∂t+1VF(uAx∂u∂x+vAy∂v∂y+wAz∂w∂z)=-1ρ∂p∂y+Gy+fy-by-RSORρVFv

    (5)

    ∂w∂t+1VF(uAx∂u∂x+vAy∂v∂y+wAz∂w∂z)=-1ρ∂p∂z+Gz+fz-bz-RSORρVFw

    여기서, Gx, Gy, Gz는 체적력에 의한 가속항, fx, fy, fz는 점성에 의한 가속항, bx, by, bz는 다공성 매체에서의 흐름손실을 의미한다.

    2.1.3 소류력 산정

    호안설계 시 제방사면 호안의 안정성 확보를 위해서는 하천의 흐름에 의하여 호안에 작용하는 소류력에 저항할 수 있는 재료 및 공법 선택이 필요하다. 국내의 경우 하천공사설계실무요령(MOLIT, 2016)에서 계획홍수량 유하 시 소류력 산정 방법을 제시하고 있다. 소류력은 하천의 평균유속을 이용하여 산정할 수 있으며, 소류력 산정식은 Eqs. (6)(7)과 같다.

    1) Schoklitsch 공식

    Schoklitsch(1934)는 Chezy 유속계수를 적용하여 소류력을 산정하였다.

    (6)

    τ=γRI=γC2V2

    여기서, τ는 소류력(N/m2), R은 동수반경(m), γ는 물의 단위중량(10.0 kN/m3), I는 에너지경사, C는 Chezy 유속계수, V는 평균유속(m/s)을 의미한다.

    2) Manning 조도계수를 고려한 공식

    Chezy 유속계수를 대신하여 Manning의 조도계수를 고려하여 소류력을 산정할 수 있다.

    (7)

    τ=γn2V2R1/3

    여기서, τ는 소류력(N/m2), R은 동수반경(m), γ는 물의 단위중량(10.0 kN/m3), n은 Manning의 조도계수, V는 평균유속(m/s)을 의미한다.

    FLOW-3D 수치모의 수행을 통하여 하천의 바닥 유속을 도출할 수 있으며, 본 연구에서는 Maning 조도계수롤 고려하여 소류력을 산정하고자 한다. 소류력을 산정하기 위해서 여수로 방류에 따른 대안부의 바닥유속 변화를 검토하여 최대 유속 값을 이용하였다. 최종적으로 산정한 소류력과 호안의 재료 및 공법에 따른 허용 소류력과 비교하여 제방사면 호안의 안정성 검토를 수행하게 된다.

    2.2 하천호안 설계기준

    하천 호안은 계획홍수위 이하의 유수작용에 대하여 안정성이 확보되도록 계획하여야 하며, 호안의 설계 시에는 사용재료의 확보용이성, 시공상의 용이성, 세굴에 대한 굴요성(flexibility) 등을 고려하여 호안의 형태, 시공방법 등을 결정한다(MOLIT, 2019). 국내의 경우, 하천공사설계실무요령(MOLIT, 2016)에서는 다양한 호안공법에 대하여 비탈경사에 따라 설계 유속을 비교하거나, 허용 소류력을 비교함으로써 호안의 안정성을 평가한다. 호안에 대한 국외의 설계기준으로 미국의 경우, ASTM(미국재료시험학회)에서 호안블록 및 식생매트 시험방법을 제시하였고 제품별로 ASTM 시험에 의한 허용유속 및 허용 소류력을 제시하였다. 일본의 경우, 호안 블록에 대한 축소실험을 통하여 항력을 측정하고 이를 통해서 호안 블록에 대한 항력계수를 제시하고 있다. 설계 시에는 항력계수에 의한 블록의 안정성을 평가하고 있으나, 최근에는 세굴의 영향을 고려할 수 있는 호안 안정성 평가의 필요성을 제기하고 있다(MOLIT, 2019). 관련된 국내·외의 하천호안 설계기준은 Table 1에 정리하여 제시하였고, 본 연구에서 하천 호안 안정성 평가 시 하천공사설계실무요령(MOLIT, 2016)과 ASTM 시험에서 제시한 허용소류력 및 허용유속 기준을 비교하여 각각 0.28 kN/m2, 5.0 m/s 미만일 경우 호안 안정성을 확보하였다고 판단하였다.

    Table 1.

    Standard of Permissible Velocity and Shear on Revetment

    Country (Reference)MaterialPermissible velocity (Vp, m/s)Permissible Shear (τp, kN/m2)
    KoreaRiver Construction Design Practice Guidelines
    (MOLIT, 2016)
    Vegetated5.00.50
    Stone5.00.80
    USAASTM D’6460Vegetated6.10.81
    Unvegetated5.00.28
    JAPANDynamic Design Method of Revetment5.0

    2.3. 보조여수로 운영에 따른 하류하천 영향 분석

    2.3.1 모형의 구축 및 경계조건

    본 연구에서는 기존 여수로의 노후화에 대비하여 홍수 시 보조여수로의 활용방안에 따른 하류하천의 흐름특성 및 호안안정성 평가를 수행하기 위해 FLOW-3D 모형을 이용하였다. 기존 여수로 및 보조 여수로는 치수능력 증대사업(MOLIT & K-water, 2004)을 통하여 완공된 ○○댐의 제원을 이용하여 구축하였다. ○○댐은 설계빈도(100년) 및 200년빈도 까지는 계획홍수위 이내로 기존 여수로를 통하여 운영이 가능하나 그 이상 홍수조절은 보조여수로를 통하여 조절해야 하며, 또한 2011년 기존 여수로 정밀안전진단 결과 사면의 표층 유실 및 옹벽 밀림현상 등이 확인되어 노후화에 따른 보수·보강이 필요한 상태이다. 이에 보조여수로의 활용방안 검토가 필요한 것으로 판단하여 본 연구의 대상댐으로 선정하였다. 하류 하천의 흐름특성을 예측하기 위하여 격자간격을 0.99 ~ 8.16 m의 크기로 하여 총 격자수는 49,102,500개로 구성하였으며, 여수로 방류에 따른 하류하천의 흐름해석을 위한 경계조건으로 상류는 유입유량(inflow), 바닥은 벽면(wall), 하류는 수위(water surface elevation)조건으로 적용하도록 하였다(Table 2Fig. 1 참조). FLOW-3D 난류모형에는 혼합길이 모형, 난류에너지 모형, k-ϵ모형, RNG(Renormalized Group Theory) k-ϵ모형, LES 모형 등이 있으며, 본 연구에서는 여수로 방류에 따른 복잡한 난류 흐름 및 높은 전단흐름을 정확하게 모의(Flow Science, 2011)할 수 있는 RNG k-ϵ모형을 사용하였고, 하류하천 호안의 안정성 측면에서 보조여수로의 활용방안을 검토하기 위하여 방류시나리오는 Table 3에 제시된 것 같이 설정하였다. Case 1 및 Case 2를 통하여 계획홍수량에 대하여 기존 여수로와 보조 여수로의 단독 운영이 하류하천에 미치는 영향을 확인하였고 보조 여수로의 방류량 조절을 통하여 호안 안정성 측면에서 보조 여수로 방류능 검토를 수행하였다(Case 3 ~ Case 6). 또한 기존 여수로와 보조 여수로의 방류량 배분에 따른 하류하천의 영향 검토(Case 7 ~ Case 10) 및 방류 배분에 따른 허용 방류량을 호안 안정성 측면에서 검토를 수행하였다(Case 11 ~ Case 14).

    수문은 완전개도 조건으로 가정하였으며 하류하천의 계획홍수량에 대한 기존 여수로와 보조여수로의 배분량을 조절하여 모의를 수행하였다. 여수로는 콘크리트의 조도계수 값(Chow, 1959)을 채택하였고, 댐 하류하천의 조도계수는 하천기본계획(Busan Construction and Management Administration, 2009) 제시된 조도계수 값을 채택하였으며 FLOW-3D의 적용을 위하여 Manning-Strickler 공식(Vanoni, 2006)을 이용하여 조도계수를 조고값으로 변환하여 사용하였다. Manning-Strickler 공식은 Eq. (8)과 같으며, FLOW-3D에 적용한 조도계수 및 조고는 Table 4와 같다.

    (8)

    n=ks1/68.1g1/2

    여기서, kS는 조고 (m), n은 Manning의 조도계수, g는 중력가속도(m/s2)를 의미한다.

    시간에 따라 동일한 유량이 일정하게 유입되도록 모의를 수행하였으며, 시간간격(Time Step)은 0.0001초로 설정(CFL number < 1.0) 하였다. 또한 여수로 수문을 통한 유량의 변동 값이 1.0%이내일 경우는 연속방정식을 만족하고 있다고 가정하였다. 이는, 유량의 변동 값이 1.0%이내일 경우 유속의 변동 값 역시 1.0%이내이며, 수치모의 결과 1.0%의 유속변동은 호안의 유속설계기준에 크게 영향을 미치지 않는다고 판단하였다. 그 결과 모든 수치모의 Case에서 2400초 이내에 결과 값이 수렴하는 것을 확인하였다.

    Table 2.

    Mesh sizes and numerical conditions

    MeshNumbers49,102,500 EA
    Increment (m)DirectionExisting SpillwayAuxiliary Spillway
    ∆X0.99 ~ 4.301.00 ~ 4.30
    ∆Y0.99 ~ 8.161.00 ~ 5.90
    ∆Z0.50 ~ 1.220.50 ~ 2.00
    Boundary ConditionsXmin / YmaxInflow / Water Surface Elevation
    Xmax, Ymin, Zmin / ZmaxWall / Symmetry
    Turbulence ModelRNG model
    Table 3.

    Case of numerical simulation (Qp : Design flood discharge)

    CaseExisting Spillway (Qe, m3/s)Auxiliary Spillway (Qa, m3/s)Remarks
    1Qp0Reference case
    20Qp
    300.58QpReview of discharge capacity on
    auxiliary spillway
    400.48Qp
    500.45Qp
    600.32Qp
    70.50Qp0.50QpDetermination of optimal division
    ratio on Spillways
    80.61Qp0.39Qp
    90.39Qp0.61Qp
    100.42Qp0.58Qp
    110.32Qp0.45QpDetermination of permissible
    division on Spillways
    120.35Qp0.48Qp
    130.38Qp0.53Qp
    140.41Qp0.56Qp
    Table 4.

    Roughness coefficient and roughness height

    CriteriaRoughness coefficient (n)Roughness height (ks, m)
    Structure (Concrete)0.0140.00061
    River0.0330.10496
    /media/sites/ksds/2021-014-02/N0240140207/images/ksds_14_02_07_F1.jpg
    Fig. 1

    Layout of spillway and river in this study

    2.3.2 보조 여수로의 방류능 검토

    본 연구에서는 기존 여수로와 보조 여수로의 방류량 배분에 따른 하류하천 대안부의 유속분포 및 수위분포를 검토하기 위해 수치모의 Case 별 다음과 같이 관심구역을 설정하였다(Fig. 2 참조). 관심구역(대안부)의 길이(L)는 총 1.3 km로 10 m 등 간격으로 나누어 검토하였으며, Section 1(0 < X/L < 0.27)은 기존 여수로 방류에 따른 영향이 지배적인 구간, Section 2(0.27 < X/L < 1.00)는 보조 여수로 방류에 따른 영향이 지배적인 구간으로 각 구간에서의 수위, 유속, 수심결과를 확인하였다. 기존 여수로의 노후화에 따른 보조 여수로의 방류능 검토를 위하여 Case 1 – Case 6까지의 결과를 비교하였다.

    보조 여수로의 단독 운영 시 기존 여수로 운영 시 보다 하류하천의 대안부의 최대 유속(Vmax)은 약 3% 감소하였으며, 이는 보조 여수로의 하천 유입각이 기존 여수로 보다 7°작으며 유입하천의 폭이 증가하여 유속이 감소한 것으로 판단된다. 대안부의 최대 유속 발생위치는 하류 쪽으로 이동하였으며 교량으로 인한 단면의 축소로 최대유속이 발생하는 것으로 판단된다. 또한 보조 여수로의 배분량(Qa)이 증가함에 따라 하류하천 대안부의 최대 유속이 증가하였다. 하천호안 설계기준에서 제시하고 있는 허용유속(Vp)과 비교한 결과, 계획홍수량(Qp)의 45% 이하(Case 5 & 6)를 보조 여수로에서 방류하게 되면 허용 유속(5.0 m/s)조건을 만족하여 호안안정성을 확보하였다(Fig. 3 참조). 허용유속 외에도 대안부에서의 소류력을 산정하여 하천호안 설계기준에서 제시한 허용 소류력(τp)과 비교한 결과, 유속과 동일하게 보조 여수로의 방류량이 계획홍수량의 45% 이하일 경우 허용소류력(0.28 kN/m2) 조건을 만족하였다(Fig. 4 참조). 각 Case 별 호안설계조건과 비교한 결과는 Table 5에 제시하였다.

    하류하천의 수위도 기존 여수로 운영 시 보다 보조 여수로 단독 운영 시 최대 수위(ηmax)가 약 2% 감소하는 효과를 보였으며 최대 수위 발생위치는 수충부로 여수로 방류시 처오름에 의한 수위 상승으로 판단된다. 기존 여수로의 단독운영(Case 1)의 수위(ηref)를 기준으로 보조 여수로의 방류량이 증가함에 따라 수위는 증가하였으나 계획홍수량의 58%까지 방류할 경우 월류에 대한 안정성(ηmax/ηref<0.97(=기설제방고))은 확보되었다(Fig. 5 참조). 그러나 계획홍수량 조건에서는 월류에 대한 위험성이 존재하기 때문에 기존여수로와 보조여수로의 적절한 방류량 배분 조합을 도출하는 것이 중요하다고 판단되어 진다.

    /media/sites/ksds/2021-014-02/N0240140207/images/ksds_14_02_07_F2.jpg
    Fig. 2

    Region of interest in this study

    /media/sites/ksds/2021-014-02/N0240140207/images/ksds_14_02_07_F3.jpg
    Fig. 3

    Maximum velocity and location of Vmax according to Qa

    /media/sites/ksds/2021-014-02/N0240140207/images/ksds_14_02_07_F4.jpg
    Fig. 4

    Maximum shear according to Qa

    /media/sites/ksds/2021-014-02/N0240140207/images/ksds_14_02_07_F5.jpg
    Fig. 5

    Maximum water surface elevation and location of ηmax according to Qa

    Table 5.

    Numerical results for each cases (Case 1 ~ Case 6)

    CaseMaximum Velocity
    (Vmax, m/s)
    Maximum Shear
    (τmax, kN/m2)
    Evaluation
    in terms of Vp
    Evaluation
    in terms of τp
    1
    (Qa = 0)
    9.150.54No GoodNo Good
    2
    (Qa = Qp)
    8.870.56No GoodNo Good
    3
    (Qa = 0.58Qp)
    6.530.40No GoodNo Good
    4
    (Qa = 0.48Qp)
    6.220.36No GoodNo Good
    5
    (Qa = 0.45Qp)
    4.220.12AccpetAccpet
    6
    (Qa = 0.32Qp)
    4.040.14AccpetAccpet

    2.3.3 기존 여수로와 보조 여수로 방류량 배분 검토

    기존 여수로 및 보조 여수로 단독운영에 따른 하류하천 및 호안의 안정성 평가를 수행한 결과 계획홍수량 방류 시 하류하천 대안부에서 호안 설계 조건(허용유속 및 허용 소류력)을 초과하였으며, 처오름에 의한 수위 상승으로 월류에 대한 위험성 증가를 확인하였다. 따라서 계획 홍수량 조건에서 기존 여수로와 보조 여수로의 방류량 배분을 통하여 호안 안정성을 확보하고 하류하천에 방류로 인한 피해를 최소화할 수 있는 배분조합(Case 7 ~ Case 10)을 검토하였다. Case 7은 기존 여수로와 보조여수로의 배분 비율을 균등하게 적용한 경우이고, Case 8은 기존 여수로의 배분량이 보조 여수로에 비하여 많은 경우, Case 9는 보조 여수로의 배분량이 기존 여수로에 비하여 많은 경우를 의미한다. 최대유속을 비교한 결과 보조 여수로의 배분 비율이 큰 경우 기존 여수로의 배분량에 의하여 흐름이 하천 중심에 집중되어 대안부의 유속을 저감하는 효과를 확인하였다. 보조여수로의 방류량 배분 비율이 증가할수록 기존 여수로 대안부 측(0.00<X/L<0.27, Section 1) 유속 분포는 감소하였으나, 신규여수로 대안부 측(0.27<X/L<1.00, Section 2) 유속은 증가하는 것을 확인하였다(Fig. 6 참조). 그러나 유속 저감 효과에도 대안부 전구간에서 설계 허용유속 조건을 초과하여 제방의 안정성을 확보하지는 못하였다. 소류력 산정 결과 유속과 동일하게 보조 여수로의 방류량이 기존 여수로의 방류량 보다 크면 감소하는 것을 확인하였고 일부 구간에서는 허용 소류력 조건을 만족하는 것을 확인하였다(Fig. 7 참조).

    따라서 유속 저감효과가 있는 배분 비율 조건(Qa>Qe)에서 Section 2에 유속 저감에 영향을 미치는 기존 여수로 방류량 배분 비율을 증가시켜 추가 검토(Case 10)를 수행하였다. 단독운영과 비교 시 하류하천에 유입되는 유량은 증가하였음에도 불구하고 기존 여수로 방류량에 의해 흐름이 하천 중심으로 집중되는 현상에 따라 대안부의 유속은 단독 운영에 비하여 감소하는 것을 확인하였고(Fig. 8 참조), 호안 설계 허용유속 및 허용 소류력 조건을 만족하는 구간이 발생하여 호안 안정성도 확보한 것으로 판단되었다. 최종적으로 각 Case 별 수위 결과의 경우 여수로 동시 운영을 수행하게 되면 대안부 전 구간에서 월류에 대한 안정성(ηmax/ηref<0.97(=기설제방고))은 확보하였다(Fig. 9 참조). 각 Case 별 대안부에서 최대 유속결과 및 산정한 소류력은 Table 6에 제시하였다.

    /media/sites/ksds/2021-014-02/N0240140207/images/ksds_14_02_07_F6.jpg
    Fig. 6

    Maximum velocity on section 1 & 2 according to Qa

    /media/sites/ksds/2021-014-02/N0240140207/images/ksds_14_02_07_F7.jpg
    Fig. 7

    Maximum shear on section 1 & 2 according to Qa

    /media/sites/ksds/2021-014-02/N0240140207/images/ksds_14_02_07_F8.jpg
    Fig. 8

    Velocity results of FLOW-3D (a: auxiliary spillway operation only , b : simultaneous operation of spillways)

    /media/sites/ksds/2021-014-02/N0240140207/images/ksds_14_02_07_F9.jpg
    Fig. 9

    Maximum water surface elevation on section 1 & 2 according to Qa

    Table 6.

    Numerical results for each cases (Case 7 ~ Case 10)

    Case (Qe &amp; Qa)Maximum Velocity (Vmax, m/s)Maximum Shear
    (τmax, kN/m2)
    Evaluation in terms of VpEvaluation in terms of τp
    Section 1Section 2Section 1Section 2Section 1Section 2Section 1Section 2
    7
    Qe : 0.50QpQa : 0.50Qp
    8.106.230.640.30No GoodNo GoodNo GoodNo Good
    8
    Qe : 0.61QpQa : 0.39Qp
    8.886.410.610.34No GoodNo GoodNo GoodNo Good
    9
    Qe : 0.39QpQa : 0.61Qp
    6.227.330.240.35No GoodNo GoodAcceptNo Good
    10
    Qe : 0.42QpQa : 0.58Qp
    6.394.790.300.19No GoodAcceptNo GoodAccept

    2.3.4 방류량 배분 비율의 허용 방류량 검토

    계획 홍수량 방류 시 기존 여수로와 보조 여수로의 배분 비율 검토 결과 Case 10(Qe = 0.42Qp, Qa = 0.58Qp)에서 방류에 따른 하류 하천의 피해를 최소화시킬 수 있는 것을 확인하였다. 그러나 대안부 전 구간에 대하여 호안 설계조건을 만족하지 못하였다. 따라서 기존 여수로와 보조 여수로의 방류 배분 비율을 고정시킨 후 총 방류량을 조절하여 허용 방류량을 검토하였다(Case 11 ~ Case 14).

    호안 안정성 측면에서 검토한 결과 계획홍수량 대비 총 방류량이 감소하면 최대 유속 및 최대 소류력이 감소하고 최종적으로 계획 홍수량의 77%를 방류할 경우 하류하천의 대안부에서 호안 설계조건을 모두 만족하는 것을 확인하였다(Fig. 10Fig. 11 참조). 각 Case 별 대안부에서 최대 유속결과 및 산정한 소류력은 Table 7에 제시하였다. 또한 Case 별 수위 검토 결과 처오름으로 인한 대안부 전 구간에서 월류에 대한 안정성(ηmax/ηref<0.97(=기설제방고))은 확보하였다(Fig. 12 참조).

    Table 7.

    Numerical results for each cases (Case 11 ~ Case 14)

    Case (Qe &amp; Qa)Maximum Velocity
    (Vmax, m/s)
    Maximum Shear
    (τmax, kN/m2)
    Evaluation in terms of VpEvaluation in terms of τp
    Section 1Section 2Section 1Section 2Section 1Section 2Section 1Section 2
    11
    Qe : 0.32QpQa : 0.45Qp
    3.634.530.090.26AcceptAcceptAcceptAccept
    12
    Qe : 0.35QpQa : 0.48Qp
    5.745.180.230.22No GoodNo GoodAcceptAccept
    13
    Qe : 0.38QpQa : 0.53Qp
    6.704.210.280.11No GoodAcceptAcceptAccept
    14
    Qe : 0.41QpQa : 0.56Qp
    6.545.240.280.24No GoodNo GoodAcceptAccept
    /media/sites/ksds/2021-014-02/N0240140207/images/ksds_14_02_07_F10.jpg
    Fig. 10

    Maximum velocity on section 1 & 2 according to total outflow

    /media/sites/ksds/2021-014-02/N0240140207/images/ksds_14_02_07_F11.jpg
    Fig. 11

    Maximum shear on section 1 & 2 according to total outflow

    /media/sites/ksds/2021-014-02/N0240140207/images/ksds_14_02_07_F12.jpg
    Fig. 12

    Maximum water surface elevation on section 1 & 2 according to total outflow

    3. 결 론

    본 연구에서는 홍수 시 기존 여수로의 노후화로 인한 보조 여수로의 활용방안에 대하여 하류하천의 호안 안정성 측면에서 검토하였다. 여수로 방류로 인한 하류하천의 흐름특성을 검토하기 위하여 3차원 수치모형인 FLOW-3D를 활용하였고, 여수로 지형은 치수능력 증대사업을 통하여 완공된 ○○댐의 제원을 이용하였다. 하류하천 조도 계수 및 여수로 방류량은 하천기본계획을 참고하여 적용하였다. 최종적으로 여수로 방류로 인한 하류하천의 피해를 최소화 시킬 수 있는 적절한 보조 여수로의 활용방안을 도출하기 위하여 보조 여수로 단독 운영과 기존 여수로와의 동시 운영에 따른 하류 하천의 흐름특성 및 소류력의 변화를 검토하였다.

    수문은 완전 개도 상태에서 방류한다는 가정으로 계획 홍수량 조건에서 보조 여수로 단독 운영 시 하류하천 대안부의 유속 및 수위를 검토한 결과 기존 여수로 단독운영에 비하여 최대 유속 및 최대 수위가 감소하는 것을 확인할 수 있었으며, 이는 보조 여수로 단독 운영 시 하류하천으로 유입각도가 작아지고, 유입되는 하천의 폭이 증가되기 때문이다. 그러나 계획 홍수량 조건에서 하천호안 설계기준에서 제시한 허용 유속(5.0 m/s)과 허용 소류력(0.28 kN/m2)과 비교하였을 때 호안 안정성을 확보하지 못하였으며, 계획홍수량의 45% 이하 방류 시에 대안부의 호안 안정성을 확보하였다. 수위의 경우 여수로 방류에 따른 대안부에서 처오름 현상이 발생하여 월류에 대한 위험성을 확인하였고 이를 통하여 기존 여수로와의 동시 운영 방안을 도출하는 것이 중요하다고 판단된다. 따라서 기존 여수로와의 동시 운영 측면에서 기존 여수로와 보조 여수로의 배분 비율 및 총 방류량을 변화시켜가며 하류 하천의 흐름특성 및 소류력의 변화를 검토하였다. 배분 비율의 경우 기존 여수로와 보조 여수로의 균등 배분(Case 7) 및 편중 배분(Case 8 & Case 9)을 검토하여 보조 여수로의 방류량이 기존 여수로의 방류량보다 큰 경우 하류하천의 중심부로 집중되어 대안부의 최대유속, 최대소류력 및 최대수위가 감소하는 것을 확인하였다. 이를 근거로 기존 여수로의 방류 비율을 증가(Qe=0.42Qp, Qa=0.58Qp)시켜 검토한 결과 대안부 일부 구간에서 허용 유속 및 허용소류력 조건을 만족하는 것을 확인하였다. 이를 통하여 기존 여수로와 보조 여수로의 동시 운영을 통하여 적절한 방류량 배분 비율을 도출하는 것이 방류로 인한 하류하천의 피해를 저감하는데 효과적인 것으로 판단된다. 그러나 설계홍수량 방류 시 전 구간에서 허용 유속 및 소류력 조건을 만족하지 못하였다. 최종적으로 전체 방류량에서 기존 여수로의 방류 비율을 42%, 보조 여수로의 방류 비율을 58%로 설정하여 허용방류량을 검토한 결과, 계획홍수량의 77%이하로 방류 시 대안부의 최대유속은 기존여수로 방류의 지배영향구간(section 1)에서 3.63 m/s, 기존 여수로와 보조 여수로 방류의 영향구간(section 2)에서 4.53 m/s로 허용유속 조건을 만족하였고, 산정한 소류력도 각각 0.09 kN/m2 및 0.26 kN/m2로 허용 소류력 조건을 만족하여 대안부 호안의 안정성을 확보하였다고 판단된다.

    본 연구 결과는 기후변화 및 기존여수로의 노후화로 인하여 홍수 시 기존여수로의 단독운영으로 하류하천의 피해가 발생할 수 있는 현시점에서 치수증대 사업으로 완공된 보조 여수로의 활용방안에 대한 기초자료로 활용될 수 있고, 향후 계획 홍수량 유입 시 최적의 배분 비율 및 허용 방류량 도출에 이용할 수 있다. 다만 본 연구는 여수로 방류에 따른 제방에 작용하는 수충력은 검토하지 못하고, 허용 유속 및 허용소류력은 제방과 유수의 방향이 일정한 구간에 대하여 검토하였다. 또한 여수로 방류에 따른 대안부에서의 영향에 대해서만 검토하였고 수문 전면 개도 조건에서 검토하였다는 한계점은 분명히 있다. 이에 향후에는 다양한 수문 개도 조건 및 방류 시나리오를 적용 및 검토하여 보다 효율적이고, 효과적인 보조 여수로 활용방안을 도출하고자 한다.

    Acknowledgements

    본 결과물은 K-water에서 수행한 기존 및 신규 여수로 효율적 연계운영 방안 마련(2021-WR-GP-76-149)의 지원을 받아 연구되었습니다.

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    6 김상호, 김지성 (2013). 충주댐 방류에 따른 댐 상하류 홍수위 영향 분석. 대한토목학회논문집. 33(2): 537-548. 10.12652/Ksce.2013.33.2.537

    7 김주성 (2007). 댐 여수로부 수리 및 수치모형실험 비교 고찰. Water for Future. 40(4): 74-81.

    8 부산국토관리청 (2009). 낙동강수계 하천기본계획(변경). 부산: 부산국토관리청.

    9 전태명, 김형일, 박형섭, 백운일 (2006). 수리모형실험과 수치모의를 이용한 비상여수로 설계-임하댐. 한국수자원학회 학술발표회. 1726-1731.

    10 한국수자원공사 (2021). 댐관리 규정. 대전: 한국수자원공사.

    Fig. 5. The predicted shapes of initial breach (a) Rectangular (b) V-notch. Fig. 6. Dam breaching stages.

    Investigating the peak outflow through a spatial embankment dam breach

    공간적 제방댐 붕괴를 통한 최대 유출량 조사

    Mahmoud T.GhonimMagdy H.MowafyMohamed N.SalemAshrafJatwaryFaculty of Engineering, Zagazig University, Zagazig 44519, Egypt

    Abstract

    Investigating the breach outflow hydrograph is an essential task to conduct mitigation plans and flood warnings. In the present study, the spatial dam breach is simulated by using a three-dimensional computational fluid dynamics model, FLOW-3D. The model parameters were adjusted by making a comparison with a previous experimental model. The different parameters (initial breach shape, dimensions, location, and dam slopes) are studied to investigate their effects on dam breaching. The results indicate that these parameters have a significant impact. The maximum erosion rate and peak outflow for the rectangular shape are higher than those for the V-notch by 8.85% and 5%, respectively. Increasing breach width or decreasing depth by 5% leads to increasing maximum erosion rate by 11% and 15%, respectively. Increasing the downstream slope angle by 4° leads to an increase in both peak outflow and maximum erosion rate by 2.0% and 6.0%, respectively.

    유출 유출 수문곡선을 조사하는 것은 완화 계획 및 홍수 경보를 수행하는 데 필수적인 작업입니다. 본 연구에서는 3차원 전산유체역학 모델인 FLOW-3D를 사용하여 공간 댐 붕괴를 시뮬레이션합니다. 이전 실험 모델과 비교하여 모델 매개변수를 조정했습니다.

    다양한 매개변수(초기 붕괴 형태, 치수, 위치 및 댐 경사)가 댐 붕괴에 미치는 영향을 조사하기 위해 연구됩니다. 결과는 이러한 매개변수가 상당한 영향을 미친다는 것을 나타냅니다. 직사각형 형태의 최대 침식율과 최대 유출량은 V-notch보다 각각 8.85%, 5% 높게 나타났습니다.

    위반 폭을 늘리거나 깊이를 5% 줄이면 최대 침식률이 각각 11% 및 15% 증가합니다. 하류 경사각을 4° 증가시키면 최대 유출량과 최대 침식률이 각각 2.0% 및 6.0% 증가합니다.

    Keywords

    Spatial dam breach; FLOW-3D; Overtopping erosion; Computational fluid dynamics (CFD)

    1. Introduction

    There are many purposes for dam construction, such as protection from flood disasters, water storage, and power generationEmbankment failures may have a catastrophic impact on lives and infrastructure in the downstream regions. One of the most common causes of embankment dam failure is overtopping. Once the overtopping of the dam begins, the breach formation will start in the dam body then end with the dam failure. This failure occurs within a very short time, which threatens to be very dangerous. Therefore, understanding and modeling the embankment breaching processes is essential for conducting mitigation plans, flood warnings, and forecasting flood damage.

    The analysis of the dam breaching process is implemented by different techniques: comparative methods, empirical models with dimensional and dimensionless solutions, physical-based models, and parametric models. These models were described in detail [1]. Parametric modeling is commonly used to simulate breach growth as a time-dependent linear process and calculate outflow discharge from the breach using hydraulics principles [2]. Alhasan et al. [3] presented a simple one-dimensional mathematical model and a computer code to simulate the dam breaching process. These models were validated by small dams breaching during the floods in 2002 in the Czech Republic. Fread [4] developed an erosion model (BREACH) based on hydraulics principles, sediment transport, and soil mechanics to estimate breach size, time of formation, and outflow discharge. Říha et al. [5] investigated the dam break process for a cascade of small dams using a simple parametric model for piping and overtopping erosion, as well as a 2D shallow-water flow model for the flood in downstream areas. Goodarzi et al. [6] implemented mathematical and statistical methods to assess the effect of inflows and wind speeds on the dam’s overtopping failure.

    Dam breaching studies can be divided into two main modes of erosion. The first mode is called “planar dam breach” where the flow overtops the whole dam width. While the second mode is called “spatial dam breach” where the flow overtops through the initial pilot channel (i.e., a channel created in the dam body). Therefore, the erosion will be in both vertical and horizontal directions [7].

    The erosion process through the embankment dams occurs due to the shear stress applied by water flows. The dam breaching evolution can be divided into three stages [8], [9], but Y. Yang et al. [10] divided the breach development into five stages: Stage I, the seepage erosion; Stage II, the initial breach formation; Stage III, the head erosion; Stage IV, the breach expansion; and Stage V, the re-equilibrium of the river channel through the breach. Many experimental tests have been carried out on non-cohesive embankment dams with an initial breach to examine the effect of upstream inflow discharges on the longitudinal profile evolution and the time to inflection point [11].

    Zhang et al. [12] studied the effect of changing downstream slope angle, sediment grain size, and dam crest length on erosion rates. They noticed that increasing dam crest length and decreasing downstream slope angle lead to decreasing sediment transport rate. While the increase in sediment grain size leads to an increased sediment transport rate at the initial stages. Höeg et al. [13] presented a series of field tests to investigate the stability of embankment dams made of various materials. Overtopping and piping were among the failure tests carried out for the dams composed of homogeneous rock-fill, clay, or gravel with a height of up to 6.0 m. Hakimzadeh et al. [14] constructed 40 homogeneous cohesive and non-cohesive embankment dams to study the effect of changing sediment diameter and dam height on the breaching process. They also used genetic programming (GP) to estimate the breach outflow. Refaiy et al. [15] studied different scenarios for the downstream drain geometry, such as length, height, and angle, to minimize the effect of piping phenomena and therefore increase dam safety.

    Zhu et al. [16] examined the effect of headcut erosion on dam breach growth, especially in the case of cohesive dams. They found that the breach growth in non-cohesive embankments is slower than cohesive embankments due to the little effect of headcut. Schmocker and Hager [7] proposed a relationship for estimating peak outflow from the dam breach process.(1)QpQin-1=1.7exp-20hc23d5013H0

    where: Qp = peak outflow discharge.

    Qin = inflow discharge.

    hc = critical flow depth.

    d50 = mean sediment diameter.

    Ho = initial dam height.

    Yu et al. [17] carried out an experimental study for homogeneous non-cohesive embankment dams in a 180° bending rectangular flume to determine the effect of overtopping flows on breaching formation. They found that the main factors influencing breach formation are water level, river discharge, and embankment material diameter.

    Wu et al. [18] carried out a series of experiments to investigate the effect of breaching geometry on both non-cohesive and cohesive embankment dams in a U-bend flume due to overtopping flows. In the case of non-cohesive embankments, the non-symmetrical lateral expansion was noticed during the breach formation. This expansion was described by a coefficient ranging from 2.7 to 3.3.

    The numerical models of the dam breach can be categorized according to different parameters, such as flow dimensions (1D, 2D, or 3D), flow governing equations, and solution methods. The 1D models are mainly used to predict the outflow hydrograph from the dam breach. Saberi et al. [19] applied the 1D Saint-Venant equation, which is solved by the finite difference method to investigate the outflow hydrograph during dam overtopping failure. Because of the ability to study dam profile evolution and breach formation, 2D models are more applicable than 1D models. Guan et al. [20] and Wu et al. [21] employed both 2D shallow water equations (SWEs) and sediment erosion equations, which are solved by the finite volume method to study the effect of the dam’s geometry parameters on outflow hydrograph and dam profile evolution. Wang et al. [22] also proposed a second-order hybrid-type of total variation diminishing (TVD) finite-difference to estimate the breach outflow by solving the 2D (SWEs). The accuracy of (SWEs) for both vertical flow contraction and surface roughness has been assessed [23]. They noted that the accuracy of (SWEs) is acceptable for milder slopes, but in the case of steeper slopes, modelers should be more careful. Generally, the accuracy of 2D models is still low, especially with velocity distribution over the flow depth, lateral momentum exchange, density-driven flows, and bottom friction [24]. Therefore, 3D models are preferred. Larocque et al. [25] and Yang et al. [26] started to use three-dimensional (3D) models that depend on the Reynolds-averaged Navier-Stokes (RANS) equations.

    Previous experimental studies concluded that there is no clear relationship between the peak outflow from the dam breach and the initial breach characteristics. Some of these studies depend on the sharp-crested weir fixed at the end of the flume to determine the peak outflow from the breach, which leads to a decrease in the accuracy of outflow calculations at the microscale. The main goals of this study are to carry out a numerical simulation for a spatial dam breach due to overtopping flows by using (FLOW-3D) software to find an empirical equation for the peak outflow discharge from the breach and determine the worst-case that leads to accelerating the dam breaching process.

    2. Numerical simulation

    The current study for spatial dam breach is simulated by using (FLOW-3D) software [27], which is a powerful computational fluid dynamics (CFD) program.

    2.1. Geometric presentations

    A stereolithographic (STL) file is prepared for each change in the initial breach geometry and dimensions. The CAD program is useful for creating solid objects and converting them to STL format, as shown in Fig. 1.

    2.2. Governing equations

    The governing equations for water flow are three-dimensional Reynolds Averaged Navier-Stokes equations (RANS).

    The continuity equation:(2)∂ui∂xi=0

    The momentum equation:(3)∂ui∂t+1VFuj∂ui∂xj=1ρ∂∂xj-pδij+ν∂ui∂xj+∂uj∂xi-ρu`iu`j¯

    where u is time-averaged velocity,ν is kinematic viscosity, VF is fractional volume open to flow, p is averaged pressure and -u`iu`j¯ are components of Reynold’s stress. The Volume of Fluid (VOF) technique is used to simulate the free surface profile. Hirt et al. [28] presented the VOF algorithm, which employs the function (F) to express the occupancy of each grid cell with fluid. The value of (F) varies from zero to unity. Zero value refers to no fluid in the grid cell, while the unity value refers to the grid cell being fully occupied with fluid. The free surface is formed in the grid cells having (F) values between zero and unity.(4)∂F∂t+1VF∂∂xFAxu+∂∂yFAyv+∂∂zFAzw=0

    where (u, v, w) are the velocity components in (x, y, z) coordinates, respectively, and (AxAyAz) are the area fractions.

    2.3. Boundary and initial conditions

    To improve the accuracy of the results, the boundary conditions should be carefully determined. In this study, two mesh blocks are used to minimize the time consumed in the simulation. The boundary conditions for mesh block 1 are as follows: The inlet and sides boundaries are defined as a wall boundary condition (wall boundary condition is usually used for bound fluid by solid regions. In the case of viscous flows, no-slip means that the tangential velocity is equal to the wall velocity and the normal velocity is zero), the outlet is defined as a symmetry boundary condition (symmetry boundary condition is usually used to reduce computational effort during CFD simulation. This condition allows the flow to be transferred from one mesh block to another. No inputs are required for this boundary condition except that its location should be defined accurately), the bottom boundary is defined as a uniform flow rate boundary condition, and the top boundary is defined as a specific pressure boundary condition with assigned atmospheric pressure. The boundary conditions for mesh block 2 are as follows: The inlet is defined as a symmetry boundary condition, the outlet is defined as a free flow boundary condition, the bottom and sides boundaries are defined as a wall boundary condition, and the top boundary is defined as a specific pressure boundary condition with assigned atmospheric pressure as shown in Fig. 2. The initial conditions required to be set for the fluid (i.e., water) inside of the domain include configuration, temperature, velocities, and pressure distribution. The configuration of water depends on the dimensions and shape of the dam reservoir. While the other conditions have been assigned as follows: temperature is normal water temperature (25 °c) and pressure distribution is hydrostatic with no initial velocity.

    2.4. Numerical method

    FLOW-3D uses the finite volume method (FVM) to solve the governing equation (Reynolds-averaged Navier-Stokes) over the computational domain. A finite-volume method is an Eulerian approach for representing and evaluating partial differential equations in algebraic equations form [29]. At discrete points on the mesh geometry, values are determined. Finite volume expresses a small volume surrounding each node point on a mesh. In this method, the divergence theorem is used to convert volume integrals with a divergence term to surface integrals. After that, these terms are evaluated as fluxes at each finite volume’s surfaces.

    2.5. Turbulent models

    Turbulence is the chaotic, unstable motion of fluids that occurs when there are insufficient stabilizing viscous forces. In FLOW-3D, there are six turbulence models available: the Prandtl mixing length model, the one-equation turbulent energy model, the two-equation (k – ε) model, the Renormalization-Group (RNG) model, the two-equation (k – ω) models, and a large eddy simulation (LES) model. For simulating flow motion, the RNG model is adopted to simulate the motion behavior better than the k – ε and k – ω.

    models [30]. The RNG model consists of two main equations for the turbulent kinetic energy KT and its dissipation.εT(5)∂kT∂t+1VFuAx∂kT∂x+vAy∂kT∂y+wAz∂kT∂z=PT+GT+DiffKT-εT(6)∂εT∂t+1VFuAx∂εT∂x+vAy∂εT∂y+wAz∂εT∂z=C1.εTKTPT+c3.GT+Diffε-c2εT2kT

    where KT is the turbulent kinetic energy, PT is the turbulent kinetic energy production, GT is the buoyancy turbulence energy, εT is the turbulent energy dissipation rate, DiffKT and Diffε are terms of diffusion, c1, c2 and c3 are dimensionless parameters, in which c1 and c3 have a constant value of 1.42 and 0.2, respectively, c2 is computed from the turbulent kinetic energy (KT) and turbulent production (PT) terms.

    2.6. Sediment scour model

    The sediment scour model available in FLOW-3D can calculate all the sediment transport processes including Entrainment transport, Bedload transport, Suspended transport, and Deposition. The erosion process starts once the water flows remove the grains from the packed bed and carry them into suspension. It happens when the applied shear stress by water flows exceeds critical shear stress. This process is represented by entrainment transport in the numerical model. After entrained, the grains carried by water flow are represented by suspended load transport. After that, some suspended grains resort to settling because of the combined effect of gravity, buoyancy, and friction. This process is described through a deposition. Finally, the grains sliding motions are represented by bedload transport in the model. For the entrainment process, the shear stress applied by the fluid motion on the packed bed surface is calculated using the standard wall function as shown in Eq.7.(7)ks,i=Cs,i∗d50

    where ks,i is the Nikuradse roughness and Cs,i is a user-defined coefficient. The critical bed shear stress is defined by a dimensionless parameter called the critical shields number as expressed in Eq.8.(8)θcr,i=τcr,i‖g‖diρi-ρf

    where θcr,i is the critical shields number, τcr,i is the critical bed shear stress, g is the absolute value of gravity acceleration, di is the diameter of the sediment grain, ρi is the density of the sediment species (i) and ρf is the density of the fluid. The value of the critical shields number is determined according to the Soulsby-Whitehouse equation.(9)θcr,i=0.31+1.2d∗,i+0.0551-exp-0.02d∗,i

    where d∗,i is the dimensionless diameter of the sediment, given by Eq.10.(10)d∗,i=diρfρi-ρf‖g‖μf213

    where μf is the fluid dynamic viscosity. For the sloping bed interface, the value of the critical shields number is modified according to Eq.11.(11)θ`cr,i=θcr,icosψsinβ+cos2βtan2φi-sin2ψsin2βtanφi

    where θ`cr,i is the modified critical shields number, φi is the angle of repose for the sediment, β is the angle of bed slope and ψ is the angle between the flow and the upslope direction. The effects of the rolling, hopping, and sliding motions of grains along the packed bed surface are taken by the bedload transport process. The volumetric bedload transport rate (qb,i) per width of the bed is expressed in Eq.12.(12)qb,i=Φi‖g‖ρi-ρfρfdi312

    where Φi is the dimensionless bedload transport rate is calculated by using Meyer Peter and Müller equation.(13)Φi=βMPM,iθi-θ`cr,i1.5cb,i

    where βMPM,i is the Meyer Peter and Müller user-defined coefficient and cb,i is the volume fraction of species i in the bed material. The suspended load transport is calculated as shown in Eq.14.(14)∂Cs,i∂t+∇∙Cs,ius,i=∇∙∇DCs,i

    where Cs,i is the suspended sediment mass concentration, D is the diffusivity, and us,i is the grain velocity of species i. Entrainment and deposition are two opposing processes that take place at the same time. The lifting and settling velocities for both entrainment and deposition processes are calculated according to Eq.15 and Eq.16, respectively.(15)ulifting,i=αid∗,i0.3θi-θ`cr,igdiρiρf-1(16)usettling,i=υfdi10.362+1.049d∗,i3-10.36

    where αi is the entrainment coefficient of species i and υf is the kinematic viscosity of the fluid.

    2.7. Grid type

    Using simple rectangular orthogonal elements in planes and hexahedral in volumes in the (FLOW-3D) program makes the mesh generation process easier, decreases the required memory, and improves numerical accuracy. Two mesh blocks were used in a joined form with a size ratio of 2:1. The first mesh block is coarser, which contains the reservoir water, and the second mesh block is finer, which contains the dam. For achieving accuracy and efficiency in results, the mesh size is determined by using a grid convergence test. The optimum uniform cell size for the first mesh block is 0.012 m and for the second mesh block is 0.006 m.

    2.8. Time step

    The maximum time step size is determined by using a Courant number, which controls the distance that the flow will travel during the simulation time step. In this study, the Courant number was taken equal to 0.25 to prevent the flow from traveling through more than one cell in the time step. Based on the Courant number, a maximum time step value of 0.00075 s was determined.

    2.9. Numerical model validation

    The numerical model accuracy was achieved by comparing the numerical model results with previous experimental results. The experimental study of Schmocker and Hager [7] was based on 31 tests with changes in six parameters (d50, Ho, Bo, Lk, XD, and Qin). All experimental tests were conducted in a straight open glass-sided flume. The horizontal flume has a rectangular cross-section with a width of 0.4 m and a height of 0.7 m. The flume was provided with a flow straightener and an intake with a length of 0.66 m. All tested dams were inserted at various distances (XD) from the intake. Test No.1 from this experimental program was chosen to validate the numerical model. The different parameters used in test No.1 are as follows:

    (1) uniform sediment with a mean diameter (d50 = 0.31 mm), (2) Ho = 0.2 m, (3) Bo = 0.2 m, (4) Lk = 0.1 m,

    (5) XD = 1.0 m, (6) Qin = 6.0 lit/s, (7) Su and Sd = 2:1, (8) mass density (ρs = 2650 kg/m3(9) Homogenous and non-cohesive embankment dam. As shown in Fig. 2, the simulation is contained within a rectangular grid with dimensions: 3.56 m in the x-direction (where 0.66 m is used as inlet, 0.9 m as dam base width, and 1.0 m as outlet), in y-direction 0.2 m (dam length), and in the z-direction 0.3 m, which represents the dam height (0.2 m) with a free distance (0.1 m) above the dam. There are two main reasons that this experimental program is preferred for the validation process. The first reason is that this program deals with homogenous, non-cohesive soil, which is available in FLOW-3D. The second reason is that this program deals with small-scale models which saves time for numerical simulation. Finally, some important assumptions were considered during the validation process. The flow is assumed to be incompressible, viscous, turbulent, and three-dimensional.

    By comparing dam profiles at different time instants for the experimental test with the current numerical model, it appears that the numerical model gives good agreement as shown in Fig. 3 and Fig. 4, with an average error percentage of 9% between the experimental results and the numerical model.

    3. Analysis and discussions

    The current model is used to study the effects of different parameters such as (initial breach shapes, dimensions, locations, upstream and downstream dam slopes) on the peak outflow discharge, QP, time of peak outflow, tP, and rate of erosion, E.

    This study consists of a group of scenarios. The first scenario is changing the shapes of the initial breach according to Singh [1], the most predicted shapes are rectangular and V-notch as shown in Fig. 5. The second scenario is changing the initial breach dimensions (i.e., width and depth). While the third scenario is changing the location of the initial breach. Eventually, the last scenario is changing the upstream and downstream dam slopes.

    All scenarios of this study were carried out under the same conditions such as inflow discharge value (Qin=1.0lit/s), dimensions of the tested dam, where dam height (Ho=0.20m), crest width.

    (Lk=0.1m), dam length (Bo=0.20m), and homogenous & non-cohesive soil with a mean diameter (d50=0.31mm).

    3.1. Dam breaching process evolution

    The dam breaching process is a very complex process due to the quick changes in hydrodynamic conditions during dam failure. The dam breaching process starts once water flows reach the downstream face of the dam. During the initial stage of dam breaching, the erosion process is relatively quiet due to low velocities of flow. As water flows continuously, erosion rates increase, especially in two main zones: the crest and the downstream face. As soon as the dam crest is totally eroded, the water levels in the dam reservoir decrease rapidly, accompanied by excessive erosion in the dam body. The erosion process continues until the water levels in the dam reservoir equal the remaining height of the dam.

    According to Zhou et al. [11], the breaching process consists of three main stages. The first stage starts with beginning overtopping flow, then ends when the erosion point directed upstream and reached the inflection point at the inflection time (ti). The second stage starts from the end of the stage1 until the occurrence of peak outflow discharge at the peak outflow time (tP). The third stage starts from the end of the stage2 until the value of outflow discharge becomes the same as the value of inflow discharge at the final time (tf). The outflow discharge from the dam breach increases rapidly during stage1 and stage2 because of the large dam storage capacity (i.e., the dam reservoir is totally full of water) and excessive erosion. While at stage3, the outflow values start to decrease slowly because most of the dam’s storage capacity was run out. The end of stage3 indicates that the dam storage capacity was totally run out, so the outflow equalized with the inflow discharge as shown in Fig. 6 and Fig. 7.

    3.2. The effect of initial breach shape

    To identify the effect of the initial breach shape on the evolution of the dam breaching process. Three tests were carried out with different cross-section areas for each shape. The initial breach is created at the center of the dam crest. Each test had an ID to make the process of arranging data easier. The rectangular shape had an ID (Rec5h & 5b), which means that its depth and width are equal to 5% of the dam height, and the V-notch shape had an ID (V-noch5h & 1:1) which means that its depth is equal to 5% of the dam height and its side slope is equal to 1:1. The comparison between rectangular and V-notch shapes is done by calculating the ratio between maximum dam height at different times (ZMax) to the initial dam height (Ho), rate of erosion, and hydrograph of outflow discharge for each test. The rectangular shape achieves maximum erosion rate and minimum inflection time, in addition to a rapid decrease in the dam reservoir levels. Therefore, the dam breaching is faster in the case of a rectangular shape than in a V-notch shape, which has the same cross-section area as shown in Fig. 8.

    Also, by comparing the hydrograph for each test, the peak outflow discharge value in the case of a rectangular shape is higher than the V-notch shape by 5% and the time of peak outflow for the rectangular shape is shorter than the V-notch shape by 9% as shown in Fig. 9.

    3.3. The effect of initial breach dimensions

    The results of the comparison between the different initial breach shapes indicate that the worst initial breach shape is rectangular, so the second scenario from this study concentrated on studying the effect of a change in the initial rectangular breach dimensions. Groups of tests were carried out with different depths and widths for the rectangular initial breach. The first group had a depth of 5% from the dam height and with three different widths of 5,10, and 15% from the dam height, the second group had a depth of 10% with three different widths of 5,10, and 15%, the third group had a depth of 15% with three different widths of 5,10, and 15% and the final group had a width of 15% with three different heights of 5, 10, and 15% for a rectangular breach shape. The comparison was made as in the previous section to determine the worst case that leads to the quick dam failure as shown in Fig. 10.

    The results show that the (Rec 5 h&15b) test achieves a maximum erosion rate for a shorter period of time and a minimum ratio for (Zmax / Ho) as shown in Fig. 10, which leads to accelerating the dam failure process. The dam breaching process is faster with the minimum initial breach depth and maximum initial breach width. In the case of a minimum initial breach depth, the retained head of water in the dam reservoir is high and the crest width at the bottom of the initial breach (L`K) is small, so the erosion point reaches the inflection point rapidly. While in the case of the maximum initial breach width, the erosion perimeter is large.

    3.4. The effect of initial breach location

    The results of the comparison between the different initial rectangular breach dimensions indicate that the worst initial breach dimension is (Rec 5 h&15b), so the third scenario from this study concentrated on studying the effect of a change in the initial breach location. Three locations were checked to determine the worst case for the dam failure process. The first location is at the center of the dam crest, which was named “Center”, the second location is at mid-distance between the dam center and dam edge, which was named “Mid”, and the third location is at the dam edge, which was named “Edge” as shown in Fig. 11. According to this scenario, the results indicate that the time of peak outflow discharge (tP) is the same in the three cases, but the maximum value of the peak outflow discharge occurs at the center location. The difference in the peak outflow values between the three cases is relatively small as shown in Fig. 12.

    The rates of erosion were also studied for the three cases. The results show that the maximum erosion rate occurs at the center location as shown in Fig. 13. By making a comparison between the three cases for the dam storage volume. The results show that the center location had the minimum values for the dam storage volume, which means that a large amount of water has passed to the downstream area as shown in Fig. 14. According to these results, the center location leads to increased erosion rate and accelerated dam failure process compared with the two other cases. Because the erosion occurs on both sides, but in the case of edge location, the erosion occurs on one side.

    3.5. The effect of upstream and downstream dam slopes

    The results of the comparison between the different initial rectangular breach locations indicate that the worst initial breach location is the center location, so the fourth scenario from this study concentrated on studying the effect of a change in the upstream (Su) and downstream (Sd) dam slopes. Three slopes were checked individually for both upstream and downstream slopes to determine the worst case for the dam failure process. The first slope value is (2H:1V), the second slope value is (2.5H:1V), and the third slope value is (3H:1V). According to this scenario, the results show that the decreasing downstream slope angle leads to increasing time of peak outflow discharge (tP) and decreasing value of peak outflow discharge. The difference in the peak outflow values between the three cases for the downstream slope is 2%, as shown in Fig. 15, but changing the upstream slope has a negligible impact on the peak outflow discharge and its time as shown in Fig. 16.

    The rates of erosion were also studied in the three cases for both upstream and downstream slopes. The results show that the maximum erosion rate increases by 6.0% with an increasing downstream slope angle by 4°, as shown in Fig. 17. The results also indicate that the erosion rates aren’t affected by increasing or decreasing the upstream slope angle, as shown in Fig. 18. According to these results, increasing the downstream slope angle leads to increased erosion rate and accelerated dam failure process compared with the upstream slope angle. Because of increasing shear stress applied by water flows in case of increasing downstream slope.

    According to all previous scenarios, the dimensionless peak outflow discharge QPQin is presented for a fixed dam height (Ho) and inflow discharge (Qin). Fig. 19 illustrates the relationship between QP∗=QPQin and.

    Lr=ho2/3∗bo2/3Ho. The deduced relationship achieves R2=0.96.(17)QP∗=2.2807exp-2.804∗Lr

    4. Conclusions

    A spatial dam breaching process was simulated by using FLOW-3D Software. The validation process was performed by making a comparison between the simulated results of dam profiles and the dam profiles obtained by Schmocker and Hager [7] in their experimental study. And also, the peak outflow value recorded an error percentage of 12% between the numerical model and the experimental study. This model was used to study the effect of initial breach shape, dimensions, location, and dam slopes on peak outflow discharge, time of peak outflow, and the erosion process. By using the parameters obtained from the validation process, the results of this study can be summarized in eight points as follows.1.

    The rectangular initial breach shape leads to an accelerating dam failure process compared with the V-notch.2.

    The value of peak outflow discharge in the case of a rectangular initial breach is higher than the V-notch shape by 5%.3.

    The time of peak outflow discharge for a rectangular initial breach is shorter than the V-notch shape by 9%.4.

    The minimum depth and maximum width for the initial breach achieve maximum erosion rates (increasing breach width, b0, or decreasing breach depth, h0, by 5% from the dam height leads to an increase in the maximum rate of erosion by 11% and 15%, respectively), so the dam failure is rapid.5.

    The center location of the initial breach leads to an accelerating dam failure compared with the edge location.6.

    The initial breach location has a negligible effect on the peak outflow discharge value and its time.7.

    Increasing the downstream slope angle by 4° leads to an increase in both peak outflow discharge and maximum rate of erosion by 2.0% and 6.0%, respectively.8.

    The upstream slope has a negligible effect on the dam breaching process.

    References

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    11. G.G.D. Zhou, M. Zhou, M.S. Shrestha, D. Song, C.E. Choi, K.F.E. Cui, et al.Experimental investigation on the longitudinal evolution of landslide dam breaching and outburst floodsGeomorphology, 334 (2019), pp. 29-43
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    Effect of roughness on separation zone dimensions.

    Experimental and numerical study of flow at a 90 degree lateral turnout with enhanced roughness coefficient and invert level changes

    조도 계수 및 역전 수준 변화가 개선된 90도 측면 분출구에서의 유동에 대한 실험적 및 수치적 연구

    Maryam BagheriSeyed M. Ali ZomorodianMasih ZolghadrH. Md. AzamathullaC. Venkata Siva Rama Prasad

    Abstract

    측면 분기기(흡입구)의 상류 측에서 흐름 분리는 분기기 입구에서 와류를 일으키는 중요한 문제입니다. 이는 흐름의 유효 폭, 출력 용량 및 효율성을 감소시킵니다. 따라서 분리지대의 크기를 파악하고 크기를 줄이기 위한 방안을 제시하는 것이 필수적이다. 본 연구에서는 분리 구역의 치수를 줄이기 위한 방법으로 7가지 유형의 거칠기 요소를 분기구 입구에 설치하고 4가지 다른 배출(총 84번의 실험을 수행)과 함께 3개의 서로 다른 베드 반전 레벨을 조사했습니다. 또한 3D CFD(Computational Fluid Dynamics) 모델을 사용하여 분리 영역의 흐름 패턴과 치수를 평가했습니다. 결과는 거칠기 계수를 향상시키면 분리 영역 치수를 최대 38%까지 줄일 수 있는 반면, 드롭 구현 효과는 사용된 거칠기 계수를 기반으로 이 영역을 다르게 축소할 수 있음을 보여주었습니다. 두 가지 방법을 결합하면 분리 영역 치수를 최대 63%까지 줄일 수 있습니다.

    Flow separation at the upstream side of lateral turnouts (intakes) is a critical issue causing eddy currents at the turnout entrance. It reduces the effective width of flow, turnout capacity and efficiency. Therefore, it is essential to identify the dimensions of the separation zone and propose remedies to reduce its dimensions. Installation of 7 types of roughening elements at the turnout entrance and 3 different bed invert levels, with 4 different discharges (making a total of 84 experiments) were examined in this study as a method to reduce the dimensions of the separation zone. Additionally, a 3-D Computational Fluid Dynamic (CFD) model was utilized to evaluate the flow pattern and dimensions of the separation zone. Results showed that enhancing the roughness coefficient can reduce the separation zone dimensions up to 38% while the drop implementation effect can scale down this area differently based on the roughness coefficient used. Combining both methods can reduce the separation zone dimensions up to 63%.

    HIGHLIGHTS

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    • Flow separation at the upstream side of lateral turnouts (intakes) is a critical issue causing eddy currents at the turnout entrance.
    • Installation of 7 types of roughening elements at the turnout entrance and 3 different bed level inverts were investigated.
    • Additionally, a 3-D Computational Fluid Dynamic (CFD) model was utilized to evaluate the flow.
    • Combining both methods can reduce the separation zone dimensions by up to 63%.
    Experimental and numerical study of flow at a 90 degree lateral turnout with enhanced roughness coefficient and invert level changes
    Experimental and numerical study of flow at a 90 degree lateral turnout with enhanced roughness coefficient and invert level changes

    Keywords

    discharge ratioflow separation zoneintakethree dimensional simulation

    INTRODUCTION

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    Turnouts or intakes are amongst the oldest and most widely used hydraulic structures in irrigation networks. Turnouts are also used in water distribution, transmission networks, power generation facilities, and waste water treatment plants etc. The flows that enter a turnout have a strong momentum in the direction of the main waterway and that is why flow separation occurs inside the turnout. The horizontal vortex formed in the separation area is a suitable place for accumulation and deposition of sediments. The separation zone is a vulnerable area for sedimentation and for reduction of effective flow due to a contracted flow region in the lateral channel. Sedimentaion in the entrance of the intake can gradually be transfered into the lateral channel and decrease the capacity of the higher order channels over time (Jalili et al. 2011). On the other hand, the existence of coarse-grained materials causes erosion and destruction of the waterway side walls and bottom. In addition, sedimentation creates conditions for vegetation to take root and damage the waterway cover, which causes water to leak from its perimeter. Therefore, it is important to investigate the pattern of the flow separation area in turnouts and provide solutions to reduce the dimensions of this area.

    The three-dimensional flow structure at turnouts is quite complex. In an experimental study by Neary & Odgaard (1993) in a 90-degree water turnout it was found that the secondary currents and separation zone varies from the bed to the water surface. They also found that at a 90-degree water turnout, the bed roughness and discharge ratio play a critical role in flow structure. They asserted that an explanation of sediment behavior at a diversion entrance requires a comprehensive understanding of 3D flow patterns around the lateral-channel entrance. In addition, they suggested that there is a strong similarity between flow in a channel bend and a diversion channel, and that this similarity can rationalize the use of bend flow models for estimation of 3D flow structures in diversion channels.

    Some of the distinctive characteristics of dividing flow in a turnout include a zone of separation immediately near the entrance of the lateral turnout (separation zone), a contracted flow region in the branch channel (contracted flow), and a stagnation point near the downstream corner of the junction (stagnation zone). In the region downstream of the junction, along the continuous far wall, separation due to flow expansion may occur (Ramamurthy et al. 2007), that is, a separation zone. This can both reduce the turnout efficiency and the effective width of flow while increasing the sediment deposition in the turnout entrance (Jalili et al. 2011). Installation of submerged vanes in the turnout entrance is a method which is already applied to reduce the size of flow separation zones. The separation zone draws sediments and floating materials into themselves. This reduces effective cross-section area and reduces transmission capacity. These results have also been obtained in past studies, including by Ramamurthy et al. (2007) and in Jalili et al. (2011). Submerged vanes (Iowa vanes) are designed in order to modify the near-bed flow pattern and bed-sediment motion in the transverse direction of the river. The vanes are installed vertically on the channel bed, at an angle of attack which is usually oriented at 10–25 degrees to the local primary flow direction. Vane height is typically 0.2–0.5 times the local water depth during design flow conditions and vane length is 2–3 times its height (Odgaard & Wang 1991). They are vortex-generating devices that generate secondary circulation, thereby redistributing sediment within the channel cross section. Several factors affect the flow separation zone such as the ratio of lateral turnout discharge to main channel discharge, angle of lateral channel with respect to the main channel flow direction and size of applied submerged vanes. Nakato et al. (1990) found that sediment management using submerged vanes in the turnout entrance to Station 3 of the Council Bluffs plant, located on the Missouri River, is applicable and efficient. The results show submerged vanes are an appropriate solution for reduction of sediment deposition in a turnout entrance. The flow was treated as 3D and tests results were obtained for the flow characteristics of dividing flows in a 90-degree sharp-edged, junction. The main and lateral channel were rectangular with the same dimensions (Ramamurthy et al., 2007).

    Keshavarzi & Habibi (2005) carried out experiments on intake with angles of 45, 67, 79 and 90 degrees in different discharge ratios and reported the optimum angle for inlet flow with the lowest flow separation area to be about 55 degrees. The predicted flow characteristics were validated using experimental data. The results indicated that the width and length of the separation zone increases with the increase in the discharge ratio Qr (ratio of outflow per unit width in the turnout to inflow per unit width in the main channel).

    Abbasi et al. (2004) performed experiments to investigate the dimensions of the flow separation zone at a lateral turnout entrance. They demonstrated that the length and width of the separation zone decreases with the increasing ratio of lateral turn-out discharge. They also found that with a reducing angle of lateral turnout, the length of the separation zone scales up and width of separation zone reduces. Then they compared their observations with results of Kasthuri & Pundarikanthan (1987) who conducted some experiments in an open-channel junction formed by channels of equal width and an angle of lateral 90 degree turnout, which showed the dimensions of the separation zone in their experiments to be smaller than in previous studies. Kasthuri & Pundarikanthan (1987) studied vortex and flow separation dimensions at the entrance of a 90 degree channel. Results showed that increasing the diversion discharge ratio can reduce the length and width of the vortex area. They also showed that the length and width of the vortex area remain constant at diversion ratios greater than 0.7. Karami Moghaddam & Keshavarzi (2007) analyzed the flow characteristics in turnouts with angles of 55 and 90 degrees. They reported that the dimensions of the separation zone decrease by increasing the discharge ratio and reducing the turnout angle with respect to the main channel. Studies about flow separation zone can be found in Jalili et al. (2011)Nikbin & Borghei (2011)Seyedian et al. (2008).

    Jamshidi et al. (2016) measured the dimensions of a flow separation zone in the presence of submerged vanes with five arrangements (parallel, stagger, compound, piney and butterflies). Results showed that the ratio of the width to the length of the separation zone (shape index) was between 0.2 and 0.28 for all arrangements.

    Karami et al. (2017) developed a 3D computational fluid dynamic (CFD) code which was calibrated by measured data. They used the model to evaluate flow pattern, diversion ratio of discharge, strength of the secondary flow, and dimensions of the vortex inside the channel in various dikes and submerged vane installation scenarios. Results showed that the diversion ratio of discharge in the diversion channel is dependent on the width of the flow separation area in the main channel. A dike, perpendicular to the flow, doubles the ratio of diverted discharge and reduces the suspended sediment load compared with the base-line situation by creating outer arch conditions. In addition, increasing the longitudinal distance between vanes increases the velocity gradient between the vanes and leads to a more severe erosion of the bed near the vanes.Figure 1VIEW LARGEDOWNLOAD SLIDE

    Laboratory channel dimensions.

    Al-Zubaidy & Hilo (2021) used the Navier–Stokes equation to study the flow of incompressible fluids. Using the CFD software ANSYS Fluent 19.2, 3D flow patterns were simulated at a diversion channel. Their results showed good agreement using the comparison between the experimental and numerical results when the k-omega turbulence viscous model was employed. Simulation of the flow pattern was then done at the lateral channel junction using a variety of geometry designs. These improvements included changing the intake’s inclination angle and chamfering and rounding the inner corner of the intake mouth instead of the sharp edge. Flow parameters at the diversion including velocity streamlines, bed shear stress, and separation zone dimensions were computed in their study. The findings demonstrated that changing the 90° lateral intake geometry can improve the flow pattern and bed shear stress at the intake junction. Consequently, sedimentation and erosion problems are reduced. According to the conclusions of their study, a branching angle of 30° to 45° is the best configuration for increasing branching channel discharge, lowering branching channel sediment concentration.

    The review of the literature shows that most of the studies deal with turnout angle, discharge ratio and implementation of vanes as techniques to reduce the area of the separation zone. This study examines the effect of roughness coefficient and drop implementation at the entrance of a 90-degree lateral turnout on the dimensions of the separation zone. As far as the authors are aware, these two variables have never been studied as a remedy to decrease the separation zone dimensions whilst enhancing turnout efficiency. Additionally, a three-dimensional numerical model is applied to simulate the flow pattern around the turnout. The numerical results are verified against experimental data.

    METHOD

    Experimental setup

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    The experiments were conducted in a 90 degree dividing flow laboratory channel. The main channel is 15 m long, 0.5 m wide and 0.4 m high and the branch channel is 3 m long, 0.35 m wide and 0.4 m high, as shown in Figure 1. The tests were carried out at 9.65 m from the beginning of the flume and were far enough from the inlet, so we were sure that the flow was fully developed. According to Kirkgöz & Ardiçlioğlu (1997) the length of the developing region would be approximantly 65 and 72 times the flow depth. In this study, the depth is 9 cm, which makes this condition.

    Both the main and lateral channel had a slope of 0.0003 with side walls of concrete. A 100 hp pump discharged the water into a stilling basin at the entrance of the main flume. The discharge was measured using an ultrasonic discharge meter around the discharge pipe. Eighty-four experiments in total were carried out at range of 0.1<Fr<0.4 (Froude numbers in main channel and upstream of turnout). The depth of water in the main channel in the experiments was 9 cm, in which case the effect of surface tension can be considered; according to research by Zolghadr & Shafai Bejestan (2020) and Zolghadr et al. (2021), when the water depth is more than 6 cm, the effect of surface tension is reduced and can be ignored given that the separation phenomenon occurs in the boundary layer, the height of the roughness creates disturbances in growth and development of the boundary layer and, as a result, separation growth is also faced with disruption and its dimensions grow less compared to smooth surfaces. Similar conditions occur in case of drop implementation. A disturbance occurs in the growth of the boundary layer and as a result the separation zone dimensions decrease. In order to investigate the effect of roughness coefficient and drop implementation on the separation zone dimensions, four different discharges (16, 18, 21, 23 l/s) in subcritical conditions, seven Manning (Strickler) roughness coefficients (0.009, 0.011, 0.017, 0.023, 0.028, 0.030, 0.032) as shown in Figure 2 and three invert elevation differences between the main channel and lateral turnout invert (0, 5 and 10 cm) at the entrance of the turnout were considered. The Manning roughness coefficient values were selected based on available and feasible values for real conditions, so that 0.009 is equivalent to galvanized sheet roughness and selected for the baseline tests. 0.011 is for concrete with neat surface, 0.017 and 0.023 are for unfinished and gunite concrete respectively. 0.030 and 0.032 values are for concrete on irregular excavated rock (Chow 1959). The roughness coefficients were created by gluing sediment particles on a thin galvanized sheet which was installed at the upstream side of the lateral turnout. The values of roughness coefficients were calculated based on the Manning-Strickler formula. For this purpose, some uniformly graded sediment samples were prepared and the Manning roughness coefficient of each sample was determined with respect to the median size (D50) value pasted into the Manning-Strickler formula. Some KMnO4 was sifted in the main channel upstream to visualize and measure the dimensions of the separation zone. Consequently, when KMnO4 approached the lateral turnout a photo of the separation zone was taken from a top view. All the experiments were recorded and several photos were taken during the experiment after stablishment of steady flow conditions. The photos were then imported to AutoCAD to measure the separation zone dimensions. Because all the shooting was done with a high-definition camera and it was possible to zoom in, the results are very accurate.Figure 2VIEW LARGEDOWNLOAD SLIDE

    Roughness plates.

    The velocity values were also recorded by a one-dimensional velocity meter at 15 cm distance from the turnout entrance and in transverse direction (perpendicular to the flow direction).

    The water level was also measured by depth gauges with a accuracy of 0.1 mm, and velocity in one direction with a single-dimensional KENEK LP 1100 with an accuracy of ±0.02 m/s (0–1 m/s), ± 0.04 m/s (1–2 m/s), ± 0.08 m/s (2–4 m/s), ±0.10 m/s (4–5 m/s).

    Numerical simulation

    ListenA FLOW-3D numerical model was utilized as a solver of the Navier-Stokes equation to simulate the three-dimensional flow field at the entrance of the turnout. The governing equations included continuity momentum equations. The continuity equation, regardless of the density of the fluid in the form of Cartesian coordinates x, y, and z, is as follows:

    formula

    (1)where uv, and w represent the velocity components in the x, y, and z directions, respectively; AxAy, and Az are the surface flow fractions in the xy, and z directions, respectively; VF denotes flow volume fraction; r is the density of the fluid; t is time; and Rsor refers to the source of the mass. Equations (2)–(4) show momentum equations in xy and z dimensions respectively :

    formula

    (2)

    formula

    (3)

    formula

    (4)where GxGy, and Gz are the accelerations caused by gravity in the xy, and z directions, respectively; and fxfy, and fz are the accelerations caused by viscosity in the xy, and z directions, respectively.

    The turbulence models used in this study were the renormalized group (RNG) models. Evaluation of the concordance of the mentioned models with experimental studies showed that the RNG model provides more accurate results.

    Two blocks of mesh were used to simulate the main channels and lateral turnout. The meshes were denser in the vicinity of the entrance of the turnout in order to increase the accuracy of computations. Boundary conditions for the main mesh block included inflow for the channel entrance (volumetric flow rate), outflow for the channel exit, ‘wall’ for the bed and the right boundary and ‘symmetry’ for the top (free surface) and left boundaries (turnout). The side wall roughness coefficient was given to the software as the Manning number in surface roughness of any component. Considering the restrictions in the available processor, a main mesh block with appropriate mesh size was defined to simulate the main flow field in the channel, while the nested mesh-block technique was utilized to create a very dense solution field near the roughness plate in order to provide accurate results around the plates and near the entrance of the lateral turnout. This technique reduced the number of required mesh elements by up to 60% in comparison with the method in which the mesh size of the main solution field was decreased to the required extent.

    The numerical outputs are verified against experimental data. The hydraulic characteristics of the experiment are shown in Table 1.Table 1

    Hydraulic conditions of the flow

    Q(L/s)FrY1 (m)Q2/Q1
    16 0.449 0.09 0.22 
    18 0.335 0.09 0.61 
    21 0.242 0.09 0.71 
    23 0.180 0.09 1.04 

    RESULTS AND DISCUSSION

    Experimental results

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    During the experiments, the dimensions of the separation zone were recorded with an HD camera. Some photos were imported to AutoCad software. Then, the separation zones dimensions were measured and compared in different scenarios.

    At the beginning, the flow pattern in the separation zone for four different hydraulic conditions was studied for seven different Manning roughness coefficients from 0.009 to 0.032. To compare the obtained results, roughness of 0.009 was considered as the base line. The percentage of reduction in separation zone area in different roughness coefficients is shown in Figure 3. According to this figure, by increasing the roughness of the turnout side wall, the separation zone area ratio reduces (ratio of separation zone area to turnout area). In other words, in any desired Froud number, the highest dimensions of the separation zone area are related to the lowest roughness coefficients. In Figure 3, ‘A’ is the area of the separation zone and ‘Ai’ represents the total area of the turnout.Figure 3VIEW LARGEDOWNLOAD SLIDE

    Effect of roughness on separation zone dimensions.Figure 4VIEW LARGEDOWNLOAD SLIDE

    Effect of roughness on separation zone dimensions.

    It should be mentioned that the separation zone dimensions change with depth, so that the area is larger at the surface than near the bed. This study measured the dimensions of this area at the surface. Figure 4 show exactly where the roughness elements were located.Figure 5VIEW LARGEDOWNLOAD SLIDE

    Comparison of separation zone for n=0.023 and n=0.032.

    Figure 5 shows images of the separation zone at n=0.023 and n=0.032 as examples, and show that the separation area at n=0.032 is smaller than that of n=0.023.

    The difference between the effect of the two 0.032 and 0.030 roughnesses is minor. In other words, the dimensions of the separation zone decreased by increasing roughness up to 0.030 and then remained with negligable changes.

    In the next step, the effect of intake invert relative to the main stream (drop) on the dimensions of the separation zone was investigated. To do this, three different invert levels were considered: (1) without drop; (2) a 5 cm drop between the main canal and intake canal; and (3) a 10 cm drop between the main canal and intake canal. The without drop mode was considered as the control state. Figure 6 shows the effect of drop implementation on separation zone dimensions. Tables 2 and 3 show the reduced percentage of separation zone areas in 5 and 10 cm drop compared to no drop conditions as the base line. It was found that the best results were obtained when a 10 cm drop was implemented.Table 2

    Decrease percentage of separation zone area in 5 cm drop

    Frn=0.011n=0.017n=0.023n=0.028n=0.030n=0.032
    0.08 10.56 11.06 25.27 33.03 35.57 36.5 
    0.121 7.66 11.14 11.88 15.93 34.59 36.25 
    0.353 1.38 2.63 8.17 14.39 31.20 31.29 
    0.362 11.54 19.56 25.73 37.89 38.31 

    Table 3

    Decrease percentage of separation zone area in 10 cm drop

    Frn=0.011n=0.017n=0.023n=0.028n=0.030n=0.032
    0.047 4.30 8.75 23.47 31.22 34.96 35.13 
    0.119 11.01 13.16 15.02 21.48 39.45 40.68 
    0.348 3.89 5.71 9.82 16.09 29 30.96 
    0.354 2.84 10.44 18.42 25.45 35.68 35.76 

    Figure 6VIEW LARGEDOWNLOAD SLIDE

    Effect of drop implementation on separation zone dimensions.

    The combined effect of drop and roughness is shown in Figure 7. According to this figure, by installing a drop structure at the entrance of the intake, the dimensions of the separation zone scales down in any desired roughness coefficient. Results indicated that by increasing the roughness coefficient or drop implementation individually, the separation zone area decreases up to 38 and 25% respectively. However, employing both techniques simultaneously can reduce the separation zone area up to 63% (Table 4). The reason for the reduction of the dimensions of the separation zone area by drop implementation can be attributed to the increase of discharge ratio. This reduces the dimensions of the separation zone area.Table 4

    Reduction in percentage of combined effect of roughness and 10 cm drop

    Qin=0.011n=0.017n=0.023n=0.028n=0.030n=0.032
    16 32.3 35.07 37.2 45.7 58.01 59.1 
    18 44.5 34.15 36.18 48.13 54.2 56.18 
    21 43.18 32.33 42.30 37.79 57.16 63.2 
    23 40.56 34.5 34.09 46.25 50.12 57.2 

    Figure 7VIEW LARGEDOWNLOAD SLIDE

    Combined effect of roughness and drop on separation zone dimensions.

    This method increases the discharge ratio (ratio of turnout to main channel discharge). The results are compatible with the literature. Some other researchers reported that increasing the discharge ratio can scale down the separation zone dimensions (Karami Moghaddam & Keshavarzi 2007Ramamurthy et al. 2007). However, these researchers employed other methods to enhance the discharge ratio. Drop implementation is simple and applicable in practice, since there is normally an elevation difference between the main and lateral canal in irrigation networks to ensure gravity flow occurance.

    Table 4 depicts the decrease in percentage of the separation zone compared to base line conditions in different arrangements of the combined tests.Figure 8VIEW LARGEDOWNLOAD SLIDE

    Velocity profiles for various roughness coefficients along turnout width.

    A comparison between the proposed methods introduced in this paper and traditional methods such as installation of submerged vanes, and changing the inlet geometry (angle, radius) was performed. Figure 8 shows the comparison of the results. The comparison shows that the new techniques can be highly influential and still practical. In this research, with no change in structural geometry (enhancement of roughness coefficient) or minor changes with respect to drop implementation, the dimensions of the separation zone are decreased noticeably. The velocity values were also recorded by a one-dimensional velocity meter at 15 cm distance from the turnout entrance and in a transverse direction (perpendicular to the flow direction). The results are shown in Figure 9.Figure 9VIEW LARGEDOWNLOAD SLIDE

    Effect of roughness on separation zone dimensions in numerical study.

    Numerical results

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    This study examined the flow patterns around the entrance of a diversion channel due to various wall roughnesses in the diversion channel. Results indicated that increasing the discharge ratio in the main channel and diversion channel reduces the area of the separation zone in the diversion channel.Figure 10VIEW LARGEDOWNLOAD SLIDE

    Comparision of the vortex area (software output) for three roughnesses (0.009, 0.023 and 0.032).A laboratory and numerical error rate of 0.2605 was calculated from the following formula,

    formula

    where Uexp is the experimental result, Unum is the numerical result, and N is the number of data.

    Figure 9 shows the effect of roughness on separation zone dimensions in numerical study. Figure 10 compares the vortex area (software output) for three roughnesses, 0.009, 0.023 and 0.032 and Figure 11 shows the flow lines (tecplot output) that indicate the effect of roughness on flow in the separation zone. Numerical analysis shows that by increasing the roughness coefficient, the dimensions of the separation zone area decrease, as shown in Figure 10 where the separation zone area at n=0.032 is less than the separation zone area at n=0.009.Figure 11VIEW LARGEDOWNLOAD SLIDE

    Comparison of vortex area in 3D mode (tecplot output) with two roughnesses (a) 0.009 and (b) 0.032.Figure 12VIEW LARGEDOWNLOAD SLIDE

    Velocity vector for flow condition Q1/422 l/s, near surface.

    The velocities intensified moving midway toward the turnout showing that the effective area is scaled down. The velocity values were almost equal to zero near the side walls as expected. As shown in Figure 12 the approach vortex area velocity decreases. Experimental and numerical measured velocity at x=0.15 m of the diversion channel compared in Figure 13 shows that away from the separation zone area, the velocity increases. All longitudinal velocity contours near the vortex area are distinctly different between different roughnesses. The separation zone is larger at less roughness both in length and width.Figure 13VIEW LARGEDOWNLOAD SLIDE

    Exprimental and numerical measured velocity.

    CONCLUSION

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    This study introduces practical and feasible methods for enhancing turnout efficiency by reducing the separation zone dimensions. Increasing the roughness coefficient and implementation of inlet drop were considered as remedies for reduction of separation zone dimensions. A data set has been compiled that fully describes the complex, 3D flow conditions present in a 90 degree turnout channel for selected flow conditions. The aim of this numerical model was to compare the results of a laboratory model in the area of the separation zone and velocity. Results showed that enhancing roughness coefficient reduce the separation zone dimensions up to 38% while the drop implementation effect can scale down this area differently based on roughness coefficient used. Combining both methods can reduce the separation zone dimensions up to 63%. Further research is proposed to investigate the effect of roughness and drop implementation on sedimentation pattern at lateral turnouts. The dimensions of the separation zone decreases with the increase of the non-dimensional parameter, due to the reduction ratio of turnout discharge increasing in all the experiments.

    This method increases the discharge ratio (ratio of turnout to main channel discharge). The results are compatible with the literature. Other researchers have reported that intensifying the discharge ratio can scale down the separation zone dimensions (Karami Moghaddam & Keshavarzi 2007Ramamurthy et al. 2007). However, they employed other methods to enhance the discharge ratio. Employing both techniques simultaneously can decrease the separation zone dimensions up to 63%. A comparison between the new methods introduced in this paper and traditional methods such as installation of submerged vanes, and changing the inlet geometry (angle, radius) was performed. The comparison shows that the new techniques can be highly influential and still practical. The numerical and laboratory models are in good agreement and show that the method used in this study has been effective in reducing the separation area. This method is simple, economical and can prevent sediment deposition in the intake canal. Results show that CFD prediction of the fluid through the separation zone at the canal intake can be predicted reasonably well and the RNG model offers the best results in terms of predictability.

    DATA AVAILABILITY STATEMENT

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    All relevant data are included in the paper or its Supplementary Information.

    REFERENCES

    Abbasi A., Ghodsian M., Habibi M. & Salehi Neishabouri S. A. 2004 Experimental investigation on dimensions of flow separation zone at lateral intakeentrance. Research & Construction; Pajouhesh va Sazandegi 62, 38–44. (In Persian).Google Scholar Al-Zubaidy R. & Hilo A. 2021 Numerical investigation of flow behavior at the lateral intake using Computational Fluid Dynamics (CFD). Materials Today: Proceedings. https://doi.org/10.1016/j.matpr.2021.11.172.Google Scholar Chow V. T. 1959 Open Channel Hydraulics. McGraw-Hill, New York.Jalili H., Hosseinzadeh Dalir A. & Farsadizadeh D. 2011 Effect of intake geometry on the sediment transport and lateral flow pattern. Iranian Water Research Journal 5 (9), 1–10. (In Persian).Google Scholar Jamshidi A., Farsadizadeh D. & Hosseinzadeh Dalir A. 2016 Variations of flow separation zone at lateral intake entrance using submerged vanes. Journal of Civil Engineering Urban 6 (3), 54–63. Journal homepage. Available from: www.ojceu.ir/main.Google Scholar Karami Moghaddam K. & Keshavarzi A. 2007 Investigation of flow structure in lateral intakes of 55° and 90° with rounded entrance edge. In: 03 National Congress on Civil Engineering University of Tabriz. Available from: https://civilica.com/doc/16317. (In Persian).Google Scholar Karami H., Farzin S., Sadrabadi M. T. & Moazeni H. 2017 Simulation of flow pattern at rectangular lateral intake with different dike and submerged vane scenarios. Journal of Water Science and Engineering 10 (3), 246–255. https://doi.org/10.1016/j.wse.2017.10.001.Google ScholarCrossref  Kasthuri B. & Pundarikanthan N. V. 1987 Discussion on separation zone at open- channel junction. Journal of Hydraulic Engineering 113 (4), 543–548.Google ScholarCrossref  Keshavarzi A. & Habibi L. 2005 Optimizing water intake angle by flow separation analysis. Journal of Irrigation and Drain 54, 543–552. https://doi.org/10.1002/ird.207.Google ScholarCrossref  Kirkgöz M. S. & Ardiçlioğlu M. 1997 Velocity profiles of developing and developed open channel flow. Journal of Hydraulic Engineering 1099–1105. 10.1061/(ASCE)0733-9429(1997)123:12(1099).Google Scholar Nakato T., Kennedy J. F. & Bauerly D. 1990 Pumpstation intake-shoaling control with submerge vanes. Journal of Hydraulic Engineering. https://doi.org/10.1061/(ASCE)0733-9429(1990)116:1(119).Google Scholar Neary V. S. & Odgaard J. A. 1993 Three-dimensional flow structure at open channel diversions. Journal of Hydraulic Engineering. ASCE 119 (11), 1224–1230. https://doi.org/10.1061/(ASCE)0733-9429(1993)119:11(1223).Google ScholarCrossref  Nikbin S. & Borghei S. M. 2011 Experimental investigation of submerged vanes effect on dimensions of flow separation zone at a 90° openchannel junction. In: 06rd National Congress on Civil Engineering University of Semnan. (In Persian). Available from: https://civilica.com/doc/120494.Google Scholar Odgaard J. A. & Wang Y. 1991 Sediment management with submerged vanes, I: theory. Journal of Hydraulic Engineering 117 (3), 267–283.Google ScholarCrossref  Ramamurthy A. S., Junying Q. & Diep V. 2007 Numerical and experimental study of dividing open-channel flows. Journal of Hydraulic Engineering. See: https://doi.org/10.1061/(ASCE)0733-9429(2007)133:10(1135).Google Scholar Seyedian S., Karami Moghaddam K. & Shafai Begestan M. 2008 Determining the optimal radius in lateral intakes of 55° and 90° using variation of flow velocity. In: 07th Iranian Hydraulic Conference. Power & Water University of Technology (PWUT). (In Persian). Available from: https://civilica.com/doc/56251.Google Scholar Zolghadr M. & Shafai Bejestan M. 2020 Six legged concrete (SLC) elements as scour countermeasures at wing wall bridge abutments. International Journal of River Basin Management. doi: 10.1080/15715124.2020.1726357.Google Scholar Zolghadr M., Zomorodian S. M. A., Shabani R. & Azamatulla H.Md. 2021 Migration of sand mining pit in rivers: an experimental, numerical and case study. Measurement. https://doi.org/10.1016/j.measurement.2020.108944.Google Scholar © 2022 The AuthorsThis is an Open Access article distributed under the terms of the Creative Commons Attribution Licence (CC BY-NC-ND 4.0), which permits copying and redistribution for non-commercial purposes with no derivatives, provided the original work is properly cited (http://creativecommons.org/licenses/by-nc-nd/4.0/).

    Figure 8: Instantaneous flow structures extracted using the Q-criterion (Qcriterion=1200) and colored by the magnitude of flow velocity.

    Hybrid modeling on 3D hydraulic features of a step-pool unit

    Chendi Zhang1
    , Yuncheng Xu1,2, Marwan A Hassan3
    , Mengzhen Xu1
    , Pukang He1
    1State Key Laboratory of Hydroscience and Engineering, Tsinghua University, Beijing, 100084, China. 2
    College of Water Resources and Civil Engineering, China Agricultural University, Beijing, 100081, China.
    5 3Department of Geography, University of British Columbia, 1984 West Mall, Vancouver BC, V6T1Z2, Canada.
    Correspondence to: Chendi Zhang (chendinorthwest@163.com) and Mengzhen Xu (mzxu@mail.tsinghua.edu.cn)

    Abstract

    스텝 풀 시스템은 계류의 일반적인 기반이며 전 세계의 하천 복원 프로젝트에 활용되었습니다. 스텝 풀 장치는 스텝 풀 기능의 형태학적 진화 및 안정성과 밀접하게 상호 작용하는 것으로 보고된 매우 균일하지 않은 수력 특성을 나타냅니다.

    그러나 스텝 풀 형태에 대한 3차원 수리학의 자세한 정보는 측정의 어려움으로 인해 부족했습니다. 이러한 지식 격차를 메우기 위해 SfM(Structure from Motion) 및 CFD(Computational Fluid Dynamics) 기술을 기반으로 하이브리드 모델을 구축했습니다. 이 모델은 CFD 시뮬레이션을 위한 입력으로 6가지 유속의 자연석으로 만든 인공 스텝 풀 장치가 있는 침대 표면의 3D 재구성을 사용했습니다.

    하이브리드 모델은 스텝 풀 장치에 대한 3D 흐름 구조의 고해상도 시각화를 제공하는 데 성공했습니다. 결과는 계단 아래의 흐름 영역의 분할, 즉 수면에서의 통합 점프, 침대 근처의 줄무늬 후류 및 그 사이의 고속 제트를 보여줍니다.

    수영장에서 난류 에너지의 매우 불균일한 분포가 밝혀졌으며 비슷한 용량을 가진 두 개의 에너지 소산기가 수영장에 공존하는 것으로 나타났습니다. 흐름 증가에 따른 풀 세굴 개발은 점프 및 후류 와류의 확장으로 이어지지만 이러한 증가는 스텝 풀 실패에 대한 임계 조건에 가까운 높은 흐름에서 점프에 대해 멈춥니다.

    음의 경사면에서 발달된 곡물 20 클러스터와 같은 미세 지반은 국부 수력학에 상당한 영향을 주지만 이러한 영향은 수영장 바닥에서 억제됩니다. 스텝 스톤의 항력은 가장 높은 흐름이 사용되기 전에 배출과 함께 증가하는 반면 양력은 더 큰 크기와 더 넓은 범위를 갖습니다. 우리의 결과는 계단 풀 형태의 복잡한 흐름 특성을 조사할 때 물리적 및 수치적 모델링을 결합한 하이브리드 모델 접근 방식의 가능성과 큰 잠재력을 강조합니다.

    Step-pool systems are common bedforms in mountain streams and have been utilized in river restoration projects around the world. Step-pool units exhibit highly non-uniform hydraulic characteristics which have been reported to closely 10 interact with the morphological evolution and stability of step-pool features. However, detailed information of the threedimensional hydraulics for step-pool morphology has been scarce due to the difficulty of measurement. To fill in this knowledge gap, we established a hybrid model based on the technologies of Structure from Motion (SfM) and computational fluid dynamics (CFD). The model used 3D reconstructions of bed surfaces with an artificial step-pool unit built by natural stones at six flow rates as inputs for CFD simulations. The hybrid model succeeded in providing high-resolution visualization 15 of 3D flow structures for the step-pool unit. The results illustrate the segmentation of flow regimes below the step, i.e., the integral jump at the water surface, streaky wake vortexes near the bed, and high-speed jets in between. The highly non-uniform distribution of turbulence energy in the pool has been revealed and two energy dissipaters with comparable capacity are found to co-exist in the pool. Pool scour development under flow increase leads to the expansion of the jump and wake vortexes but this increase stops for the jump at high flows close to the critical condition for step-pool failure. The micro-bedforms as grain 20 clusters developed on the negative slope affect the local hydraulics significantly but this influence is suppressed at pool bottom. The drag forces on the step stones increase with discharge before the highest flow is used while the lift force has a larger magnitude and wider varying range. Our results highlight the feasibility and great potential of the hybrid model approach combining physical and numerical modeling in investigating the complex flow characteristics of step-pool morphology.

    Figure 1: Workflow of the hybrid modeling. SfM-MVS refers to the technology of Structure from Motion with Multi View Stereo. DSM is short for digital surface model. RNG-VOF is short for Renormalized Group (RNG) k-ε turbulence model coupled with Volume of Fluid method.
    Figure 1: Workflow of the hybrid modeling. SfM-MVS refers to the technology of Structure from Motion with Multi View Stereo. DSM is short for digital surface model. RNG-VOF is short for Renormalized Group (RNG) k-ε turbulence model coupled with Volume of Fluid method.
    Figure 2: Flume experiment settings in Zhang et al., (2020): (a) the artificially built-up step-pool model using natural stones, with stone number labelled; (b) the unsteady hydrograph of the run of CIFR (continually-increasing-flow-rate) T2 used in this study.
    Figure 2: Flume experiment settings in Zhang et al., (2020): (a) the artificially built-up step-pool model using natural stones, with stone number labelled; (b) the unsteady hydrograph of the run of CIFR (continually-increasing-flow-rate) T2 used in this study.
    Figure 3: Setup of the CFD model: (a) three-dimensional digital surface model (DSM) of the step-pool unit by structure from motion with multi view stereo (SfM-MVS) method as the input to the 3D computational fluid dynamics (CFD) modeling; (b) extruded bed 160 surface model connected to the extra downstream component (in purple blue) and rectangular columns to fill leaks (in green), with the boundary conditions shown on mesh planes; (c) recognized geometry with mesh grids of two mesh blocks shown where MS is short for mesh size; (d) sampling volumes to capture the flow forces acting on each step stone at X, Y, and Z directions; and (e) an example for the simulated 3D flow over the step-pool unit colored by velocity magnitude at the discharge of 49.9 L/s. The abbreviations for boundary conditions in (b) are: V for specified velocity; C for continuative; P for specific pressure; and W for wall 165 condition. The contraction section in Figure (e) refers to the edge between the jet and jump at water surface.
    Figure 3: Setup of the CFD model: (a) three-dimensional digital surface model (DSM) of the step-pool unit by structure from motion with multi view stereo (SfM-MVS) method as the input to the 3D computational fluid dynamics (CFD) modeling; (b) extruded bed 160 surface model connected to the extra downstream component (in purple blue) and rectangular columns to fill leaks (in green), with the boundary conditions shown on mesh planes; (c) recognized geometry with mesh grids of two mesh blocks shown where MS is short for mesh size; (d) sampling volumes to capture the flow forces acting on each step stone at X, Y, and Z directions; and (e) an example for the simulated 3D flow over the step-pool unit colored by velocity magnitude at the discharge of 49.9 L/s. The abbreviations for boundary conditions in (b) are: V for specified velocity; C for continuative; P for specific pressure; and W for wall 165 condition. The contraction section in Figure (e) refers to the edge between the jet and jump at water surface.
    Figure 4: Distribution of time-averaged velocity magnitude (VM_mean) and vectors in three longitudinal sections. The section at Y = 0 cm goes across the keystone while the other two (Y = -18 and 13.5 cm) are located at the step stones beside the keystone with 265 lower top elevations. Q refers to the discharge at the inlet of the computational domain. The spacing for X, Y, and Z axes are all 10 cm in the plots.
    Figure 4: Distribution of time-averaged velocity magnitude (VM_mean) and vectors in three longitudinal sections. The section at Y = 0 cm goes across the keystone while the other two (Y = -18 and 13.5 cm) are located at the step stones beside the keystone with lower top elevations. Q refers to the discharge at the inlet of the computational domain. The spacing for X, Y, and Z axes are all 10 cm in the plots.
    Figure 5: Distribution of time-averaged flow velocity at five cross sections which are set according to the reference section (x0). The reference cross section x0 is located at the downstream end of the keystone (KS). The five sections are located at 18 cm and 6 cm upstream of the reference section (x0-18 and x0-6), and 2 cm, 15 cm and 40 cm downstream of the reference section (x0+2, x0+15, x0+40). The spacing for X, Y, and Z axes are all 10 cm in the plots.
    Figure 5: Distribution of time-averaged flow velocity at five cross sections which are set according to the reference section (x0). The reference cross section x0 is located at the downstream end of the keystone (KS). The five sections are located at 18 cm and 6 cm upstream of the reference section (x0-18 and x0-6), and 2 cm, 15 cm and 40 cm downstream of the reference section (x0+2, x0+15, x0+40). The spacing for X, Y, and Z axes are all 10 cm in the plots.
    Figure 6: Distribution of the time-averaged turbulence kinetic energy (TKE) at the five cross sections same with Figure 3.
    Figure 6: Distribution of the time-averaged turbulence kinetic energy (TKE) at the five cross sections same with Figure 3.
    Figure 7: Boxplots for the distributions of the mass-averaged flow kinetic energy (KE, panels a-f), turbulence kinetic energy (TKE, panels g-l), and turbulent dissipation (εT, panels m-r) in the pool for all the six tested discharges (the plots at the same discharge are in the same row). The mass-averaged values were calculated every 2 cm in the streamwise direction. The flow direction is from left to right in all the plots. The general locations of the contraction section for all the flow rates are marked by the dashed lines, except for Q = 5 L/s when the jump is located too close to the step. The longitudinal distance taken up by negative slope in the pool for the inspected range is shown by shaded area in each plot.
    Figure 7: Boxplots for the distributions of the mass-averaged flow kinetic energy (KE, panels a-f), turbulence kinetic energy (TKE, panels g-l), and turbulent dissipation (εT, panels m-r) in the pool for all the six tested discharges (the plots at the same discharge are in the same row). The mass-averaged values were calculated every 2 cm in the streamwise direction. The flow direction is from left to right in all the plots. The general locations of the contraction section for all the flow rates are marked by the dashed lines, except for Q = 5 L/s when the jump is located too close to the step. The longitudinal distance taken up by negative slope in the pool for the inspected range is shown by shaded area in each plot.
    Figure 8: Instantaneous flow structures extracted using the Q-criterion (Qcriterion=1200) and colored by the magnitude of flow velocity.
    Figure 8: Instantaneous flow structures extracted using the Q-criterion (Qcriterion=1200) and colored by the magnitude of flow velocity.
    Figure 9: Time-averaged dynamic pressure (DP_mean) on the bed surface in the step-pool model under the two highest discharges, with the step numbers marked. The negative values in the plots result from the setting of standard atmospheric pressure = 0 Pa, whose absolute value is 1.013×105 Pa.
    Figure 9: Time-averaged dynamic pressure (DP_mean) on the bed surface in the step-pool model under the two highest discharges, with the step numbers marked. The negative values in the plots result from the setting of standard atmospheric pressure = 0 Pa, whose absolute value is 1.013×105 Pa.
    Figure 10: Time-averaged shear stress (SS_mean) on bed surface in the step-pool model, with the step numbers marked. The standard atmospheric pressure is set as 0 Pa.
    Figure 10: Time-averaged shear stress (SS_mean) on bed surface in the step-pool model, with the step numbers marked. The standard atmospheric pressure is set as 0 Pa.
    Figure 11: Variation of fluid force components and magnitude of resultant flow force acting on step stones with flow rate. The stone 4 is the keystone. Stone numbers are consistent with those in Fig. 9-10. The upper limit of the sampling volumes for flow force calculation is higher than water surface while the lower limit is set at 3 cm lower than the keystone crest.
    Figure 11: Variation of fluid force components and magnitude of resultant flow force acting on step stones with flow rate. The stone 4 is the keystone. Stone numbers are consistent with those in Fig. 9-10. The upper limit of the sampling volumes for flow force calculation is higher than water surface while the lower limit is set at 3 cm lower than the keystone crest.
    Figure 12: Variation of drag (CD) and lift (CL) coefficient of the step stones along with flow rate. Stone numbers are consistent with those in Fig. 8-9. KS is short for keystone. The negative values of CD correspond to the drag forces towards the upstream while the negative values of CL correspond to lift forces pointing downwards.
    Figure 12: Variation of drag (CD) and lift (CL) coefficient of the step stones along with flow rate. Stone numbers are consistent with those in Fig. 8-9. KS is short for keystone. The negative values of CD correspond to the drag forces towards the upstream while the negative values of CL correspond to lift forces pointing downwards.
    Figure 13: Longitudinal distributions of section-averaged and -integral turbulent kinetic energy (TKE) for the jump and wake vortexes at the largest three discharges. The flow direction is from left to right in all the plots. The general locations of the contraction sections under the three flow rates are marked by dashed lines in figures (d) to (f).
    Figure 13: Longitudinal distributions of section-averaged and -integral turbulent kinetic energy (TKE) for the jump and wake vortexes at the largest three discharges. The flow direction is from left to right in all the plots. The general locations of the contraction sections under the three flow rates are marked by dashed lines in figures (d) to (f).
    Figure A1: Water surface profiles of the simulations with different mesh sizes at the discharge of 43.6 L/s at the longitudinal sections at: (a) Y = 24.5 cm (left boundary); (b) Y = 0.3 cm (middle section); (c) Y = -24.5 cm (right boundary). MS is short for mesh size. The flow direction is from left to right in each plot.
    Figure A1: Water surface profiles of the simulations with different mesh sizes at the discharge of 43.6 L/s at the longitudinal sections at: (a) Y = 24.5 cm (left boundary); (b) Y = 0.3 cm (middle section); (c) Y = -24.5 cm (right boundary). MS is short for mesh size. The flow direction is from left to right in each plot.
    Figure A2: Contours of velocity magnitude in the longitudinal section at Y = 0 cm at different mesh sizes (MSs) under the flow condition with the discharge of 43.6 L/s: (a) 0.50 cm; (b) 0.375 cm; (c) 0.30 cm; (d) 0.27 cm; (e) 0.25 cm; (f) 0.24 cm. The flow direction is from left to right.
    Figure A2: Contours of velocity magnitude in the longitudinal section at Y = 0 cm at different mesh sizes (MSs) under the flow condition with the discharge of 43.6 L/s: (a) 0.50 cm; (b) 0.375 cm; (c) 0.30 cm; (d) 0.27 cm; (e) 0.25 cm; (f) 0.24 cm. The flow direction is from left to right.
    Figure A3: Measurements of water surfaces (orange lines) used in model verification: (a) water surface profiles from both sides of the flume; (b) upstream edge of the jump regime from top view. KS refers to keystone in figure (b).
    Figure A3: Measurements of water surfaces (orange lines) used in model verification: (a) water surface profiles from both sides of the flume; (b) upstream edge of the jump regime from top view. KS refers to keystone in figure (b).
    Figure A15. Figure (a) shows the locations of the cross sections and target coarse grains at Q = 49.9 L/s. Figures (b) to (e) show the distribution of velocity magnitude (VM_mean) in the four chosen cross sections: (a) x0+8.0; (b) x0+14.0; (c) x0+21.5; (d) x0+42.5. G1 to G6 refer to 6 protruding grains in the micro-bedforms in the pool.
    Figure A15. Figure (a) shows the locations of the cross sections and target coarse grains at Q = 49.9 L/s. Figures (b) to (e) show the distribution of velocity magnitude (VM_mean) in the four chosen cross sections: (a) x0+8.0; (b) x0+14.0; (c) x0+21.5; (d) x0+42.5. G1 to G6 refer to 6 protruding grains in the micro-bedforms in the pool.
    Figure A16. The distribution of turbulent kinetic energy (TKE) in the same cross sections as in figure S15: (a) x0+8.0; (b) x0+14.0; (c) x0+21.5; (d) x0+42.5.
    Figure A16. The distribution of turbulent kinetic energy (TKE) in the same cross sections as in figure S15: (a) x0+8.0; (b) x0+14.0; (c) x0+21.5; (d) x0+42.5.

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    Numerical study of the effect of flow velocity and flood roughness components on hydraulic flow performance in composite sections with converging floodplains

    Numerical study of the effect of flow velocity and flood roughness components on hydraulic flow performance in composite sections with converging floodplains

    Authors

    1 Civil Enigneering Department, Lahijan Branch.Islamic Azad University.Lahijan.Iran

    2 Department of Civil Engnieering, University of Qom,Qom,Iran

    3 Civil Engineering Department, Lahijan Branch,Islamic Azad Univeristy,Lahijan,Iran

    Abstract

    홍수와 그 위험을 통제해야 할 필요성은 누구에게도 숨겨져 있지 않습니다. 또한 이 현상으로 인해 다양한 경제, 사회 및 환경 문제가 영향을 받습니다. 홍수 제어 방법의 설계 및 최적 관리의 첫 번째 단계는 홍수 중 하천 거동을 올바르게 식별하는 것입니다.

    홍수 경로 지정, 하상 및 하천 면적 결정 등과 같은 대부분의 하천 엔지니어링 프로젝트에서 하천 단면의 수리학적 매개변수의 평균값을 계산하는 것으로 충분합니다. 오늘날 유체 환경 연구에서 수치 및 분석 방법의 사용이 성장하고 발전했습니다.

    신뢰할 수 있는 결과 생성으로 인해 물리적 모델에 대한 좋은 대안이 될 수 있었습니다. 오늘날 수치 모델의 급속한 발전과 컴퓨터 계산 속도의 증가로 인해 3D 수치 모델의 사용이 선호되며 또한 강의 속도 분포 및 전단 응력을 측정하는 데 시간이 많이 걸리고 비용이 많이 들기 때문에 결과 3D 수치 모델의 가치가 있을 것입니다.

    한편, 본 연구에서는 복합단면에 대해 FLOW-3D 모델을 이용한 종합적인 수치연구가 이루어지지 않았음을 보여주고 있어 적절한 연구기반을 제공하고 있습니다.

    따라서 본 연구의 혁신은 발산 및 수렴 범람원을 동반하는 비 각형 복합 단면에서 흐름의 상태 및 수리 성능에 대한 거칠기와 같은 매개 변수의 영향에 대한 수치 연구입니다.

    수치해석 결과를 검증하기 위해 Younesi(2013) 연구를 이용하였습니다. 이 실험에서는 먼저 고정층이 있는 복합 프리즘 및 비 프리즘 단면의 수리 흐름을 조사한 다음 조건을 유지하면서 프리즘 및 비 프리즘 모드에서 퇴적물 이동 실험을 수행했습니다.

    실험은 15미터 길이의 연구 채널에서 수행되었습니다. 이 운하는 초당 250리터의 시스템에서 재순환을 위해 제공될 수 있는 유속과 0.0088 000의 종경사를 가진 폭 400mm의 두 개의 대칭 범람원이 있는 합성 운하입니다. 범람원의 가장자리는 0.18미터와 같고 주요 운하의 너비는 0.4미터와 같습니다(그림 1).

    본수로의 바닥과 벽을 거칠게 하기 위해 평균직경 0.65mm의 퇴적물을 사용하였으며, 각 단계에서 범람원의 벽과 바닥은 평균직경 0.65, 1.3, 1.78의 퇴적물로 거칠게 하였습다. (mm). 삼각형 오버플로는 운하 상류에서 운하로의 유입량을 측정하는 데 사용됩니다.

    상대깊이 0.15와 0.25, 직경 14mm의 마이크로몰리나 실험과 상대깊이 0.35의 실험에서는 유속을 측정하기 위해 3차원 속도계(ADV)를 사용하였습니다. 수위는 0.1mm의 정확도로 깊이 게이지로 측정 되었습니다.

    본 연구에서는 수면 프로파일의 수치적 모델을 검증하기 위해 실험 0.25-2에서 발산대의 시작, 중간 및 끝에서 세 단면의 평균 깊이 속도 분포 및 경계 전단 응력) -11.3-NP 및 0.25-2-5.7-NP 및 또한 각형 복합 단면의 0.25-2-2 P 테스트가 평가되었습니다.

    각형 합성 단면의 P.20-2-2-P 테스트와 관련된 RMSE 및 NRMSE 지수 값 및 표 (2) 실험 11.3에서 RMSE 및 NRMSE 지수 값 -2-0.25-NP 및 -0.25. 2-5.7-NP가 제공됩니다. 실험 0.25-2-5.7-NP-11.3-2-0.25, NP 및 P.2.0-2-2-P의 평균 깊이 속도의 검증과 관련된 결과가 표시됩니다. 0.25-2-5.7-NP 실험에서 초, 중, 기말 NRMSE의 양은 각각 5.7, 11.8, 10.3%로 계산되었으며, 이는 초급이 우수, 중급이 양호, 최종 성적. 배치. 보시다시피, RMSE 값은 각각 0.026, 0.037 및 0.026으로 계산됩니다.

    실험 11.3-2-0.25, NP에서 초급, 중급 및 최종 수준의 NRMSE 값은 각각 7, 11.2 및 15.4%로 계산되었으며, 이는 초급에서 우수 범주 및 우수 범주에서 중간 및 최종 수준. 가져 가다. 보시다시피, RMSE 값은 각각 0.032, 0.038, 0.04로 계산됩니다. 0.25-2-P 실험에서 NRMSE 값은 1.7%로 계산되어 우수 범주에 속한다. 보시다시피 RMSE 값도 0.004로 계산됩니다. 중간 깊이의 속도 분포와 관련하여 수치 모델은 실험실 결과에 적합하며 접합 영역에 작은 오류만 입력되었다고 말할 수 있습니다. 이는 2차 전지의 이동 결과로 간주될 수 있습니다. 모서리를 향해.
    결론: 본 연구에서는 3차원 유동 해석이 가능한 Flow 3D 소프트웨어를 사용하여 각형 및 비각형 단면이 복합된 수로의 유동 패턴을 조사했습니다. 3개의 다른 상대 거칠기(1, 2 및 2.74)와 3개의 상대 깊이(0.15, 0.25 및 0.35) 및 5.7 및 11.3도의 발산 각도에 대해 속도의 세로 성분 변화, 평균 깊이 속도 분포, 경계 범람원에 의해 전달되는 유속뿐만 아니라 전단 응력 분포를 조사했습니다.

    결과는 수로를 따라 범람원의 폭이 증가함에 따라 유속량이 감소함을 보여주었다. 또한 조도가 유동패턴에 미치는 영향에 대한 연구는 일반적으로 벽의 거칠기에 따라 모든 구간에서 유속량이 감소하는 것으로 나타났으며, 또한 본관과 범람원의 교차점에서의 유동패턴은 벽의 거칠기 영향을 더 많이 받는 것으로 나타났습니다. 결과는 또한 상대 깊이가 증가하거나 상대 거칠기가 감소함에 따라 주 수로와 범람원 사이의 속도 구배가 감소함을 보여주었습니다.

    Intrpduction: The need to control floods and their dangers is not hidden from anyone. In addition, a wide range of economic, social and environmental issues are affected by this phenomenon. The first step in the design and optimal management of flood control methods is the correct identification of river behavior during floods. In most river engineering projects such as flood routing, determining the bed and river area, etc., calculating the average values of hydraulic parameters of the river section is sufficient. Today, the use of numerical and analytical methods in the study of fluid environment have grown and developed. Due to the production of reliable results, they have been able to be a good alternative to physical models. Today, with the rapid development of numerical models and increasing the speed of computer calculations, the use of 3D numerical models is preferred and also due to the fact that measuring the velocity distribution and shear stress in rivers is very time consuming and expensive, the results of 3D numerical models It will be valuable. On the other hand, the present studies show that comprehensive numerical research using FLOW-3D model has not been performed on composite sections, so a suitable ground for research is provided. Therefore, the innovation of the present study is the numerical study of the effects of parameters such as roughness on the status and hydraulic performance of the flow in non-prismatic composite sections, which are accompanied by divergent and convergent floodplains, which have received less attention numerically.

    Methodology: Younesi (2013) research has been used to validate the results of numerical simulation. In these experiments, first the hydraulic flow in composite prismatic and non-prismatic sections with fixed bed was examined and then, while maintaining the conditions, sediment transfer experiments were performed in prismatic and non-prismatic mode. The experiments were performed in a research channel 15 meters long. This canal is a composite canal with two symmetrical floodplains with a width of 400 mm with a flow rate that can be provided for recirculation in the system of 250 liters per second and a longitudinal slope of 0.0088 000. The depth of the main canal to the edge of the floodplain is equal to 0.18 meters and the width of the main canal is equal to 0.4 meters (Figure 1). In order to roughen the bed and walls of the main canal, sediments with an average diameter of 0.65 mm have been used and at each stage, the walls and bed of floodplains have been roughened by sediments with an average diameter of 0.65, 1.3 and 1.78 (mm). A triangular overflow is used to measure the inflow to the canal, upstream of the canal. In order to measure the flow velocity in experiments with relative depth of 0.15 and 0.25, a micromolina with a diameter of 14 mm and in experiments with relative depth of 0.35, a three-dimensional speedometer (ADV) was used. The water level was also taken by depth gauges with an accuracy of 0.1 mm.
    Result and Diccussion: In the present study, in order to validate the numerical model of water surface profile, average depth velocity distribution and boundary shear stress in the three sections at the beginning, middle and end of the divergence zone) in experiments 0.25-2-11.3-NP and 0.25-2-5.7-NP and Also, the 0.25-2-2 P test of the prismatic composite section has been evaluated. In Table (1) the values of RMSE and NRMSE indices related to the P.20-2-2-P test of the prismatic composite section, and also in Table (2) the values of the RMSE and NRMSE indices in the experiments 11.3-2-0.25-NP and -0.25. 2-5.7-NP is provided. The results related to the validation of the average depth velocity of the experiments 0.25-2-5.7- NP-11.3-2-0.25, NP and P.2.0-2-2-P are shown. In 0.25-2-5.7-NP experiment, the amount of NRMSE in elementary, middle and final grades was calculated to be 5.7, 11.8 and 10.3%, respectively, which is in the excellent grade in the elementary grade and good in the middle and final grades. Placed. As can be seen, the RMSE values are calculated as 0.026, 0.037 and 0.026, respectively. In the experiment 11.3-2-0.25, NP, the NRMSE values in the primary, middle and final levels were calculated as 7, 11.2 and 15.4%, respectively, which are in the excellent category in the primary level and in the good category in the middle and final levels. Take. As can be seen, the RMSE values are calculated as 0.032, 0.038 and 0.04, respectively. In the 0.25-2-P experiment, the NRMSE value was calculated to be 1.7%, which is in the excellent category. As can be seen, the RMSE value is also calculated to be 0.004. Regarding the medium-depth velocity distribution, it can be said that the numerical model has an acceptable compliance with the laboratory results and only a small error has been entered in the junction area, which can be considered as a result of the movement of secondary cells towards the corners.
    Conclusion: in this research The flow pattern in waterways with composite prismatic and non-prismatic sections was investigated using Flow 3D software that is capable of three-dimensional flow analysis. For three different relative roughnesses (1, 2 and 2.74) as well as three relative depths (0.15, 0.25 and 0.35) and divergence angles of 5.7 and 11.3 degrees, changes in the longitudinal component of velocity, The average depth velocity distribution, the boundary shear stress distribution as well as the flow rate transmitted by the floodplains were investigated. The results showed that with increasing the width of floodplains along the canal, the amount of velocity decreases. Also, the study of the effect of roughness on the flow pattern showed that in general, with wall roughness, the amount of velocity has decreased in all sections and also the flow pattern at the junction of the main canal and floodplain is more affected by wall roughness. The results also showed that with increasing relative depth or decreasing relative roughness, the velocity gradient between the main channel and floodplains decreases

    Keywords

    Figure 10 | Contour lines of the static pressure (Pa) for the standard form of the stepped spillway with discharge of 60 liters/second.

    스키밍 흐름 영역에서 계단형 여수로의 수리 성능에 대한 삼각형 프리즘 요소의 영향: 실험 연구 및 수치 모델링

    The effect of triangular prismatic elements on the hydraulic performance of stepped spillways in the skimming flow regime: an experimental study and numerical modeling 

    Kiyoumars RoushangarSamira AkhgarSaman Shahnazi

    계단식 여수로는 댐의 여수로 위로 흐르는 큰 물의 에너지를 분산시키는 비용 효율적인 유압 구조입니다. 이 연구에서는 삼각주형 요소(TPE)가 계단식 배수로의 수력 성능에 미치는 영향에 초점을 맞췄습니다. 9개의 계단식 배수로 모델이 TPE의 다양한 모양과 레이아웃으로 실험 및 수치적으로 조사되었습니다. 적절한 난류 모델을 채택하려면 RNG k – ε 및 표준 k – ε모델을 활용했습니다. 계산 모델 결과는 계단 표면의 속도 분포 및 압력 프로파일을 포함하여 실험 사례의 계단 여수로에 대한 복잡한 흐름을 만족스럽게 시뮬레이션했습니다. 결과는 계단식 여수로에 TPE를 설치하는 것이 캐비테이션 효과를 줄이는 효과적인 방법이 될 수 있음을 나타냅니다. 계단식 여수로에 TPE를 설치하면 에너지 소실률이 최대 54% 증가했습니다. 계단식 배수로의 성능은 TPE가 더 가깝게 배치되었을 때 개선되었습니다. 또한, 실험 데이터를 이용하여 거칠기 계수( f )와 임계 깊이 대 단차 거칠기( yc / k )의 비율 사이의 관계를 높은 정확도로 얻었다.

    Keywords

    energy dissipationFlow-3Droughness coefficientstepped spillwaytriangular prismatic elements

    에너지 소산 , Flow-3D , 거칠기 계수 , 계단식 배수로 , 삼각형 프리즘 요소

    Figure 1 | General schematics of laboratory flume facilities.
    Figure 1 | General schematics of laboratory flume facilities.
    Figure 2 | Different layouts of the selected TPE in the experimental study (y1 and y2 are initial, and sequent depths of hydraulic jump).
    Figure 2 | Different layouts of the selected TPE in the experimental study (y1 and y2 are initial, and sequent depths of hydraulic jump).
    Figure 3 | Geometry and alignment of TPE in the numerical study.
    Figure 3 | Geometry and alignment of TPE in the numerical study.
    Figure 5 | Comparison of turbulence models in Flow-3D.
    Figure 5 | Comparison of turbulence models in Flow-3D.
    Figure 6 | Sequent water depths versus unit flow rate in standard stepped spillways and stepped spillways with triangular TPEs of types A and B.
    Figure 6 | Sequent water depths versus unit flow rate in standard stepped spillways and stepped spillways with triangular TPEs of types A and B.
    Figure 7 | Energy dissipation for the standard stepped spillway and the stepped spillway with TPEs.
    Figure 7 | Energy dissipation for the standard stepped spillway and the stepped spillway with TPEs.
    Figure 8 | Positions of measurement points to investigate the pressure and velocity distributions on the stepped spillway
    Figure 8 | Positions of measurement points to investigate the pressure and velocity distributions on the stepped spillway
    Figure 9 | Velocity distributions on the vertical surface of step number 4.
    Figure 9 | Velocity distributions on the vertical surface of step number 4.
    Figure 10 | Contour lines of the static pressure (Pa) for the standard form of the stepped spillway with discharge of 60 liters/second.
    Figure 10 | Contour lines of the static pressure (Pa) for the standard form of the stepped spillway with discharge of 60 liters/second.
    Figure 11 | Pressure distribution on the vertical surface of the fourth step.
    Figure 11 | Pressure distribution on the vertical surface of the fourth step.
    Figure 12 | Horizontal profile of the pressure distribution on the floor of step 4.
    Figure 12 | Horizontal profile of the pressure distribution on the floor of step 4.
    Figure 13 | Roughness coefficient changes with various unit discharges for stepped spillways.
    Figure 13 | Roughness coefficient changes with various unit discharges for stepped spillways.
    Figure 14 | Variations of sequent depth of downstream with various unit discharges for stepped spillways.
    Figure 14 | Variations of sequent depth of downstream with various unit discharges for stepped spillways.
    Figure 15 | Energy dissipation rate changes with various unit discharges for different stepped spillways.
    Figure 15 | Energy dissipation rate changes with various unit discharges for different stepped spillways.
    Figure 16 | Roughness coefficients (f ) versus the critical depth to the step roughness ratio (yc/K).
    Figure 16 | Roughness coefficients (f ) versus the critical depth to the step roughness ratio (yc/K).

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    Figure 13 | Velocity vector for flow condition Q¼22 l/s, Near surface.

    Experimental and numerical study of flow at a 90 degree lateral turn-out with enhanced roughness coefficient and invert elevation changes

    조도 계수 및 역 고도 변화가 향상된 90도 측면 회전에서 유동의 실험 및 수치 연구

    Maryam Bagheria, Seyed M. Ali Zomorodianb, Masih Zolghadrc, H. MD. Azamathulla d,*
    and C. Venkata Siva Rama Prasade
    a Hydraulic Structures, Department of Water Engineering, Shiraz University, Shiraz, Iran
    b Department of Water Engineering, College of Agriculture, Shiraz University, Shiraz, Iran
    c Department of Water Sciences Engineering, College of Agriculture, Jahrom University, Jahrom, Iran
    d Civil & Environmental Engineering, The University of the West Indies, St. Augustine Campus, Port of Spain, Trinidad
    e Department of Civil Engineering, St. Peters Engineering College, Hyderabad, India
    *Corresponding author. E-mail: azmatheditor@gmail.com

    ABSTRACT

    Flow separation at the upstream side of the lateral turnouts (intakes) is a critical issue causing eddy currents at the turn-out entrance. It reduces the effective width of flow, turn-out capacity and efficiency.

    Therefore, it is essential to identify the dimensions of the separation zone and propose remedies to reduce its dimensions. Installation of 7 types of roughening elements at the turn-out entrance and 3 different bed level inverts, with 4 different discharges (total of 84 experiments) were examined in this study as a method to reduce the dimensions of
    the separation zone.

    Additionally, a 3-D Computational Fluid Dynamic (CFD) model was utilized to evaluate the flow pattern and dimensions of the separation zone. Results showed that enhancing the roughness coefficient can reduce the separation zone dimensions up to 38% while the drop implementation effect can scale down this area differently based on the roughness coefficient used. Combining both methods can reduce the separation zone dimensions up to 63%.

    측면 분기기(흡입구)의 상류 측에서 흐름 분리는 분기기 입구에서 와류를 일으키는 중요한 문제입니다. 이는 흐름의 유효 폭, 턴아웃 용량 및 효율성을 감소시킵니다. 따라서 분리지대의 크기를 파악하고 크기를 줄이기 위한 방안을 제시하는 것이 필수적이다.

    이 연구에서는 분리 구역의 치수를 줄이기 위한 방법으로 4가지 다른 배출(총 84개 실험)과 함께 7가지 유형의 조면화 요소를 출구 입구에 설치하고 3가지 서로 다른 베드 레벨 반전 장치를 조사했습니다.

    또한 3D CFD(Computational Fluid Dynamics) 모델을 사용하여 분리 영역의 흐름 패턴과 치수를 평가했습니다. 결과는 거칠기 계수를 향상시키면 분리 영역 치수를 최대 38%까지 줄일 수 있는 반면 드롭 구현 효과는 사용된 거칠기 계수를 기반으로 이 영역을 다르게 축소할 수 있음을 보여주었습니다.

    두 가지 방법을 결합하면 분리 영역 치수를 최대 63%까지 줄일 수 있습니다.

    Key words

    discharge ratio, flow separation zone, intake, three dimensional simulation

    Experimental and numerical study of flow at a 90 degree lateral turn-out with enhanced roughness coefficient and invert elevation changes
    Experimental and numerical study of flow at a 90 degree lateral turn-out with enhanced roughness coefficient and invert elevation changes
    Figure 2 | Roughness plates.
    Figure 2 | Roughness plates.
    Figure 3 | Effect of roughness on separation zone dimensions
    Figure 3 | Effect of roughness on separation zone dimensions
    Figure 4 | Effect of roughness on separation zone dimensions.
    Figure 4 | Effect of roughness on separation zone dimensions.
    Figure 5 | Comparison of separation zone for n¼0.023 and n¼0.032.
    Figure 5 | Comparison of separation zone for n¼0.023 and n¼0.032.
    Figure 6 | Effect of drop implementation on separation zone dimensions
    Figure 6 | Effect of drop implementation on separation zone dimensions
    Figure 7 | Combined effect of roughness and drop on separation zone dimensions
    Figure 7 | Combined effect of roughness and drop on separation zone dimensions
    Figure 8 | Non- dimensional Length of separation zone (Lr) variations against relative unit discharge per width (qr) in present study compared with other methods.
    Figure 8 | Non- dimensional Length of separation zone (Lr) variations against relative unit discharge per width (qr) in present study compared with other methods.
    Figure 9 | Velocity profiles for various roughness coefficients along turn-out width.
    Figure 9 | Velocity profiles for various roughness coefficients along turn-out width.
    Figure 10 | Effect of roughness on sepration zone dimensions in numerical study
    Figure 10 | Effect of roughness on sepration zone dimensions in numerical study
    Figure 11 | Comparision of the vortex area (software output) with three roughness (0.009, 0.023 and 0.032).
    Figure 11 | Comparision of the vortex area (software output) with three roughness (0.009, 0.023 and 0.032).
    Figure 12 | Comparison of vortex area in 3D mode (tecplot output) with two roughness (a) 0.009 and (b) 0.032
    Figure 12 | Comparison of vortex area in 3D mode (tecplot output) with two roughness (a) 0.009 and (b) 0.032
    Figure 13 | Velocity vector for flow condition Q¼22 l/s, Near surface.
    Figure 13 | Velocity vector for flow condition Q¼22 l/s, Near surface.
    Figure 14 | Exprimental and numerical measured velocity.
    Figure 14 | Exprimental and numerical measured velocity.

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    Figura 1. Parámetros del medidor Palmer-Bowlus

    Three-Dimensional Numerical Modeling of the Palmer-Bowlus Measuring Flume Applying the FLOW-3D Software.

    TOAPAXI-ALVAREZ*, JorgeSILA-BASTIDA, Roberto    TORRES-JACOBOWITZ, Cristina.

    The Palmer-Bowlus flume was developed in 1936, as an adaptation of the Venturi flume for the use in sewer systems, due to the difficulty in modifying the pipe invert. There are commercially available single-body Palmer-Bowlus flume with their respective discharge curves, which increase the cost of sewer projects. Based on the physical model of the Palmer-Bowlus flume (Torres & Vásquez, 2010), the aim of this research was to carry out the three-dimensional numerical modeling of these flow meters, considering four pipe diameters: 160 mm, 200 mm, 250 mm and 400 mm; the selected diameters are the most used ones, according to the information provided by the Empresa Pública Metropolitana de Agua Potable y Saneamiento de Quito (EPMAPS). The discharge curves were calibrated and validated using the FLOW-3D program. Meshing had a great influence on the quality results and duration of the numerical simulation; in contrast, the roughness and turbulence models (RNG y k-e) had little influence. The discharge curves obtained in the numerical modeling have good approximation to those obtained in the physical model.

    Palmer-Bowlus 수로는 1936년에 하수도 시스템에 사용하기 위해 Venturi 수로를 개조한 것으로 파이프 인버트를 수정하는 것이 어렵기 때문에 개발되었습니다. 각각의 배출 곡선이 있는 시판되는 단일 몸체 Palmer-Bowlus 수로가 있으며, 이는 하수도 프로젝트 비용을 증가시킵니다.

    Palmer-Bowlus 수로의 물리적 모델을 기반으로(Torres & Vásquez, 2010), 이 연구의 목적은 160mm, 200mm, 4개의 파이프 직경을 고려하여 이러한 유량계의 3차원 수치 모델링을 수행하는 것이었습니다. 250mm 및 400mm; Empresa Pública Metropolitana de Agua Potable y Sanaeamiento de Quito(EPMAPS)에서 제공한 정보에 따르면 선택한 지름이 가장 많이 사용되는 지름입니다.

    방전 곡선은 FLOW-3D 프로그램을 사용하여 보정 및 검증되었습니다. 메싱은 수치 시뮬레이션의 품질 결과와 기간에 큰 영향을 미쳤습니다. 대조적으로, 거칠기 및 난류 모델(RNG y k-e)은 거의 영향을 미치지 않았습니다. 수치 모델링에서 얻은 방전 곡선은 물리적 모델에서 얻은 것과 유사합니다.

    Figura 1. Parámetros del medidor Palmer-Bowlus
    Figura 1. Parámetros del medidor Palmer-Bowlus
    Figura 2. Diagrama de flujo de la modelación del medidor Palmer-Bowlus en FLOW-3D
    Figura 2. Diagrama de flujo de la modelación del medidor Palmer-Bowlus en FLOW-3D
    Figura 3. Captura de pantalla del modelo numérico Q=22.047( 𝑙 𝑠 ), Ho=20.038 cm
    Figura 3. Captura de pantalla del modelo numérico Q=22.047( 𝑙 𝑠 ), Ho=20.038 cm

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    Fig. 4. Numerical modeling of dual spillways: (a) Andong-1; (b) Andong-2; (c) Imha-1; (d) Juam-1; (e) Andong-3; (f) Imha-2; (g) Imha-3; and (h) Juam-3.

    Interference of Dual Spillways Operations

    Jai Hong Lee, Ph.D., P.E., M.ASCE; Pierre Y. Julien, Ph.D., M.ASCE; and Christopher I. Thornton, Ph.D., P.E., M.ASCE

    Abstract

    이중 여수로 간섭은 여수로가 서로 가깝게 배치될 때 수압 성능의 손실을 나타냅니다. 배수로 간섭은 물리적 실험과 수치 시뮬레이션을 모두 사용하여 조사됩니다.

    이중 여수로 구성의 4개 물리적 모델의 단계 및 배출 측정값을 한국의 4개 댐 부지에서 Flow-3D 계산 결과와 비교합니다.

    두 개의 배수로를 함께 사용하는 것을 각 배수로의 단일 작동과 비교합니다. 두 여수로를 동시에 운영할 경우 두 여수로를 통한 총 유량은 최대 7.6%까지 감소합니다.

    간섭 계수는 단계 He가 설계 단계 Hd를 초과하고 두 배수로를 분리하는 거리 D가 배수로 너비 W에 비해 짧을 때 가장 중요합니다. 매개변수 DHd/WHe는 계산 및 측정된 간섭 계수와 매우 잘 관련됩니다.

    안동댐 설계방류에 대한 홍수경로 예시는 간섭계수를 적용한 경우와 적용하지 않은 경우 저수지 수위의 차이가 42cm임을 보여줍니다. 결과적으로 댐 안전을 위해 추가 여수로의 너비(간섭 계수 포함)를 늘려야 합니다.

    Dual spillway interference refers to the loss of hydraulic performance of spillways when they are placed close together. Spillway interference is examined using both physical experiments and numerical simulations. Stage and discharge measurements from four physical models with dual spillways configurations are compared to the Flow-3D computational results at four dam sites in South Korea. The conjunctive use of two spillways is compared with the singular operation of each spillway. When both spillways are operated at the same time, the total flow rate through the two spillways is reduced by up to 7.6%. Interference coefficients are most significant when the stage He exceeds the design stage Hd and when the distance D separating two spillways is short compared to the spillway width W. The parameter DHd/WHecorrelates very well with the calculated and measured interference coefficients. A flood routing example for the design discharge at Andong dam shows a 42 cm difference in reservoir water level with and without application of the interference coefficient. Consequently, the width of additional spillways (including the interference coefficient) should be increased for dam safety.

    Fig. 1. Definition sketch for dual spillways
    Fig. 1. Definition sketch for dual spillways
    Fig. 2. Stage-discharge rating curves for dual spillway operations.
    Fig. 2. Stage-discharge rating curves for dual spillway operations.
    Fig. 3. Physical modeling of dual spillways: (a) Andong-1; (b) Andong-2; (c) Imha-1; and (d) Juam-1
    Fig. 3. Physical modeling of dual spillways: (a) Andong-1; (b) Andong-2; (c) Imha-1; and (d) Juam-1
    Fig. 4. Numerical modeling of dual spillways: (a) Andong-1; (b) Andong-2; (c) Imha-1; (d) Juam-1; (e) Andong-3; (f) Imha-2; (g) Imha-3; and (h) Juam-3.
    Fig. 4. Numerical modeling of dual spillways: (a) Andong-1; (b) Andong-2; (c) Imha-1; (d) Juam-1; (e) Andong-3; (f) Imha-2; (g) Imha-3; and (h) Juam-3.
    Fig. 4. (Continued.)
    Fig. 4. (Continued.)
    Fig. 5. Meshes and calculation domain for numerical modeling of Andong dam.
    Fig. 5. Meshes and calculation domain for numerical modeling of Andong dam.
    Fig. 6. Stage-discharge rating curve for existing and additional spillways (Andong-1): (a) existing spillway; (b) additional spillway; and (c) dual spillway simulations.
    Fig. 6. Stage-discharge rating curve for existing and additional spillways (Andong-1): (a) existing spillway; (b) additional spillway; and (c) dual spillway simulations.
    Fig. 7. Discharge comparison of physical experiments and numerical simulations. The upper panel is the comparative result for the existing spillway (ES) and the lower panel is for the additional spillway (AS) at four dams.
    Fig. 7. Discharge comparison of physical experiments and numerical simulations. The upper panel is the comparative result for the existing spillway (ES) and the lower panel is for the additional spillway (AS) at four dams.
    Fig. 8. Interference coefficients for dual spillways simulations with various scenarios.
    Fig. 8. Interference coefficients for dual spillways simulations with various scenarios.
    Fig. 9. Regression model for the distance-width ratio (D=W) and head ratio (Hd=He) by dual spillway simulations
    Fig. 9. Regression model for the distance-width ratio (D=W) and head ratio (Hd=He) by dual spillway simulations
    Fig. 10. Physical and numerical model validation: (a) numerical modeling; (b) solids of overflow weir of the spillway; and (c) physical models of reservoir and spillway
    Fig. 10. Physical and numerical model validation: (a) numerical modeling; (b) solids of overflow weir of the spillway; and (c) physical models of reservoir and spillway
    Fig. 11. Interference coefficients for dual spillways operations with various scenarios. The dashed lines indicate the results of the validation model with dual conditions of 1 þ 2, 1 þ 4, 1 þ 6, 3 þ 4, and 4 þ 5.
    Fig. 11. Interference coefficients for dual spillways operations with various scenarios. The dashed lines indicate the results of the validation model with dual conditions of 1 þ 2, 1 þ 4, 1 þ 6, 3 þ 4, and 4 þ 5.
    Fig. 12. Results of reservoir operations under the PMF at Andong dam.
    Fig. 12. Results of reservoir operations under the PMF at Andong dam.

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    Mesh conditions: a) mesh block; b) computational cells c) boundary conditions applied in simulation

    FLOW-3D를 이용한 Λ자 단차가 있는 계단식 배수로의 에너지 소산 조건 연구

    A Study of the Conditions of Energy Dissipation in Stepped Spillways with Λ-shaped step Using FLOW-3D

    Authors:

    Abbas Mansoori at Islamic Azad University

    Abbas Mansoori

    Shadi Erfanian

    Abstract and Figures

    본 연구에서는 특정 유형의 계단식 배수로에서 에너지 소산을 조사했습니다. 목적은 여수로 하류에서 최고 수준의 에너지 소산을 달성하는 것이었습니다.

    큰 러프니스로 계단에 대한 특정 유형의 기하학을 제공하여 수행되었습니다. 여기에서 계단은 흐름에 대한 큰 거칠기로 인식되었습니다.

    이 단계에서 최대 흐름 에너지가 최소화될 수 있도록 모양과 수를 설계했습니다. 따라서 하류의 구조에서 가장 높은 에너지 소산률을 얻을 수 있다고 말할 수 있습니다. 또한, 이에 따라 프로젝트에서 저유조를 설계하고 건설함으로써 부과되는 막대한 비용을 최소화할 수 있었습니다.

    이 연구에서는 FLOW-3D를 사용하여 에너지 소산율을 분석하고 구했습니다. 최대 에너지 소산을 달성할 수 있는 계단의 최상의 기하학은 관련 문헌을 검토하고 FLOW-3D에서 제안된 모델을 발명하여 결정되었습니다.

    제안된 방법을 평가하기 위해 앞서 언급한 방법들과 함께 시행착오를 통해 메쉬망 크기를 분석하고 그 결과를 다른 연구들과 비교하였습니다. 즉, 스무드 스텝에 비해 에너지 소산율이 25도 각도에서 Λ자 스텝으로 가장 최적의 상태를 얻었습니다.

    In the present study, energy dissipation was investigated in a specific type of stepped spillways. The purpose was to achieve the highest level of energy dissipation in downstream of the spillway. It was performed by providing a specific type of geometry for step as a great roughness. Here, steps were recognized as great roughness against flow. Their shape and number were designed in such a way that the maximum flow energy can be minimized in this stage, i.e. over steps before reaching to downstream. Accordingly, it can be stated that the highest energy dissipation rate will be obtained in the structure at downstream. Moreover, thereby, heavy costs imposed by designing and constructing stilling basin on project can be minimized. In this study, FLOW-3D was employed to analyse and obtain energy dissipation rate. The best geometry of the steps, through which the maximum energy dissipation can be achieved, was determined by reviewing related literature and inventing the proposed model in FLOW-3D. To evaluate the proposed method, analyses were performed using trial and error in mesh networks sizes as well as the mentioned methods and the results were compared to other studies. In other words, the most optimal state was obtained with Λ-shaped step at angel of 25 degree with respect to energy dissipation rate compare to smooth step.

    Figure 2. Three-dimensional design of the spillway using SolidWorks 2012
    Figure 2. Three-dimensional design of the spillway using SolidWorks 2012
    The results obtained from energy dissipation computation
    Geometrical characteristics of the í µíº²-shaped stepped spillway To investigate flow filed and hydraulic conditions, boundary and initial conditions should be applied to each of the models in FLOW-3D. 
    Mesh conditions: a) mesh block; b) computational cells; c) boundary conditions applied in simulation 
    Figure 6. a) 3D Numerical modelling of flow over Spillway; b) 3D experimental modelling of flow over Spillway (with the discharge of  )
    Figure 6. a) 3D Numerical modelling of flow over Spillway; b) 3D experimental modelling of flow over Spillway (with the discharge of  )
    Figure 7. 2D model of flow depth for each angle of the-shaped steps
    Figure 7. 2D model of flow depth for each angle of the-shaped steps

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    Figure 1- Schematic diagram of pooled stepped spillway conducted by Felder et al. (2012A): Notes: h step height (10 cm): w pool height (3.1 cm): l horizontal step length (20 cm): lw pool weir length (1.5 cm): d' is the water depth above the crest; y' is the distance normal to the crest invert

    Study of inception point, void fraction and pressure over pooled stepped spillways using Flow-3D

    Khosro Morovati , Afshin Eghbalzadeh 
    International Journal of Numerical Methods for Heat & Fluid Flow

    ISSN: 0961-5539

    Article publication date: 3 April 2018

    Abstract

    많은 계단식 배수로 지오메트리 설계 지침이 평평한 단계를 위해 개발되었지만 통합 단계를 설계하는 것이 더 효율적으로 작동하는 배수로에 대한 적절한 대안이 될 수 있습니다.

    이 논문은 POOL의 다른 높이에서 공기 연행과 보이드 비율의 시작점을 다루는 것을 목표로 합니다. 그 후, FLOW-3D 소프트웨어를 사용하여 POOL과 경사면의 높이를 다르게 하여 폭기된 지역과 폭기되지 않은 지역에서 압력 분포를 평가했습니다.

    얻어진 수치 결과와 실험 결과의 비교는 본 연구에 사용된 모든 방류에 대해 잘 일치했습니다. POOL 높이는 시작 지점 위치에 미미한 영향을 미쳤습니다. 공극률의 값은 높은 방류에 비해 낮은 방전에서 더 많은 영향을 받았습니다.

    여수로의 마루(통기되지 않은 지역)에서는 음압이 나타나지 않았으며 각 방류에서 마루를 따라 높이가 15cm인 수영장에서 최대 압력 값이 얻어졌습니다.

    모든 사면에서 웅덩이 및 평평한 계단형 여수로의 계단층 부근에서는 음압이 형성되지 않았습니다. 그러나 평단식 여수로에 비해 평단식 여수로의 수직면 부근에서 음압이 더 많이 형성되어 평단식 슈트에서 캐비테이션 현상이 발생할 확률이 증가하였습니다.

    Study of inception point, void fraction and pressure over pooled
    stWhile many stepped spillways geometry design guidelines were developed for flat steps, designing pooled steps might be an appropriate alternative to spillways working more efficiency. This paper aims to deal with the inception point of air-entrainment and void fraction in the different height of the pools. Following that, pressure distribution was evaluated in aerated and non-aerated regions under the effect of different heights of the pools and slopes through the use of the FLOW-3D software. Comparison of obtained numerical results with experimental ones was in good agreement for all discharges used in this study. Pools height had the insignificant effect on the inception point location. The value of void fraction was more affected in lower discharges in comparison with higher ones. Negative pressure was not seen over the crest of spillway (non-aerated region), and the maximum pressure values were obtained for pools with 15 cm height along the crest in each discharge. In all slopes, negative pressure was not formed near the step bed in the pooled and flat stepped spillways. However, negative pressure was formed in more area near the vertical face in the flat stepped spillway compared with the pooled stepped spillway which increases the probability of cavitation phenomenon in the flat stepped chute.

    Design/methodology/approach

    압력, 공극률 및 시작점을 평가하기 위해 POOL된 계단식 여수로가 사용되었습니다. 또한 POOL의 다른 높이가 사용되었습니다. 이 연구의 수치 시뮬레이션은 Flow-3D 소프트웨어를 통해 수행되었습니다. 얻어진 결과는 풀이 압력, 공극률 및 시작점을 포함한 2상 유동 특성에 영향을 미칠 수 있음을 나타냅니다.

    Findings

    마루 위에는 음압이 보이지 않았습니다. 압력 값은 사용된 모든 높이와 15cm 높이에서 얻은 최대 값에 대해 다릅니다. 또한, 풀링 스텝은 플랫 케이스에 비해 음압점 감소에 더 효과적인 역할을 하였습니다. 시작 지점 위치는 특히 9 및 15cm 높이에 대해 스키밍 흐름 영역과 비교하여 낮잠 및 전환 흐름 영역에서 더 많은 영향을 받았습니다.

    Keywords

    Citation

    Morovati, K. and Eghbalzadeh, A. (2018), “Study of inception point, void fraction and pressure over pooled stepped spillways using Flow-3D”, International Journal of Numerical Methods for Heat & Fluid Flow, Vol. 28 No. 4, pp. 982-998. https://doi.org/10.1108/HFF-03-2017-0112

    Figure 1- Schematic diagram of pooled stepped spillway conducted by Felder et al. (2012A): Notes: h  step height (10 cm): w pool height (3.1 cm): l horizontal step length (20 cm): lw pool weir length (1.5 cm):  d' is the water depth above the crest; y' is the distance normal to the crest invert
    Figure 1- Schematic diagram of pooled stepped spillway conducted by Felder et al. (2012A): Notes: h step height (10 cm): w pool height (3.1 cm): l horizontal step length (20 cm): lw pool weir length (1.5 cm): d’ is the water depth above the crest; y’ is the distance normal to the crest invert
    Figure 2- meshing domain and distribution of blocks
    Figure 2- meshing domain and distribution of blocks
    Figure 3- Comparison of numerical simulation with experimental data by Felder et al. (2012A);  mesh convergence analysis; pooled stepped spillway (slope: 26.6 0 )
    Figure 3- Comparison of numerical simulation with experimental data by Felder et al. (2012A); mesh convergence analysis; pooled stepped spillway (slope: 26.6 0 )
    Figure 4- Comparison of numerical simulation with experimental data by Felder et al. (2012A);  Flat stepped spillway (slope: 0 26 6. )
    Figure 4- Comparison of numerical simulation with experimental data by Felder et al. (2012A); Flat stepped spillway (slope: 0 26 6. )
    Figure 5-Comparison of numerical simulation with experimental data by Felder et al. (2012B); pooled  and flat stepped spillways (slope: 0 9.8 )
    Figure 5-Comparison of numerical simulation with experimental data by Felder et al. (2012B); pooled and flat stepped spillways (slope: 0 9.8 )
    Figure 6- TKE distribution on steps 8, 9 and 10 for four different mesh numbers: 261252 (model 1),  288941 (model 2), 323578 (model 3) and 343154 (model 4)
    Figure 6- TKE distribution on steps 8, 9 and 10 for four different mesh numbers: 261252 (model 1), 288941 (model 2), 323578 (model 3) and 343154 (model 4)
    Figure 7- Comparison of obtained Void fraction distribution on step 10 in numerical simulation with  experimental work conducted by Felder et al. (2012A); (slope 26.60 )
    Figure 7- Comparison of obtained Void fraction distribution on step 10 in numerical simulation with experimental work conducted by Felder et al. (2012A); (slope 26.60 )
    Figure 8- Results of inception point of air entrainment in different height of the pools: comparison with  empirical correlations (Eqs 8-9), experimental (Felder et al. (2012A)) and numerical data
    Figure 8- Results of inception point of air entrainment in different height of the pools: comparison with empirical correlations (Eqs 8-9), experimental (Felder et al. (2012A)) and numerical data
    Figure 9- Void fraction distribution for different pool heights on steps 10; slope 26.6 0
    Figure 9- Void fraction distribution for different pool heights on steps 10; slope 26.6 0
    Figure 10- Comparison of pressure distribution between numerical simulation and experimental work  conducted by Zhang and Chanson (2016); flat stepped spillway (slope: 0 45 )
    Figure 10- Comparison of pressure distribution between numerical simulation and experimental work conducted by Zhang and Chanson (2016); flat stepped spillway (slope: 0 45 )
    Figure 11- A comparison of the pressure distribution above the crest of the spillway; B comparison of the  free surface profile along the crest of the spillway.  Note: x' indicates the longitudinal distance from the starting point of the crest.
    Figure 11- A comparison of the pressure distribution above the crest of the spillway; B comparison of the free surface profile along the crest of the spillway. Note: x’ indicates the longitudinal distance from the starting point of the crest.
    Figure 12- pressure distribution along crest of spillway in different discharges; slope 26.6
    Figure 12- pressure distribution along crest of spillway in different discharges; slope 26.6
    Figure 13- Pressure distribution near the last step bed for different slopes and discharges: x'' indicatesthe  longitudinal distance from the intersection of the horizontal and vertical faces of step 10; y" is the distance from the intersection of the horizontal and vertical faces in the vertical direction
    Figure 13- Pressure distribution near the last step bed for different slopes and discharges: x” indicatesthe longitudinal distance from the intersection of the horizontal and vertical faces of step 10; y” is the distance from the intersection of the horizontal and vertical faces in the vertical direction
    Figure 14- Pressure distribution adjacent the vertical face of step 9 for different discharges and slopes
    Figure 14- Pressure distribution adjacent the vertical face of step 9 for different discharges and slopes
    Table1- Used discharges for assessments of mesh convergence analysis and hydraulic  characteristics
    Table1- Used discharges for assessments of mesh convergence analysis and hydraulic characteristics

    Conclusion

    본 연구에서는 자유표면을 모사하기 위해 VOF 방법과 k -ε (RNG) 난류 모델을 활용하여 FLOW-3D 소프트웨어를 사용하였고, 계단식 배수로의 유동을 모사하기 위한 목적으로 난류 특성을 모사하였다. 얻은 결과는 수치 모델이 시작점 위치, 보이드 비율 및 압력을 적절하게 시뮬레이션했음을 나타냅니다. 풀의 높이는 공기 유입 위치에 미미한 영향을 미치므로 얻은 결과는 이 문서에서 제시된 상관 관계와 잘 일치했습니다. 즉, 사용 가능한 상관 관계를 서로 다른 풀 높이에 사용할 수 있습니다. 공극률의 결과는 스텝 풀 근처의 나프 유동 영역에서 공극율 값이 다른 배출보다 더 큰 것으로 나타났다. 더욱이 고방출량 .0 113m3/s에서 수영장 높이를 변경해도 수영장 표면 근처의 공극률 값에는 영향을 미치지 않았습니다.

    낮잠 및 전환 체제의 압력 분포에 대한 0 및 3cm 높이의 수영장 효과는 많은 지점에서 대부분 유사했습니다. 더욱이 조사된 모든 높이에서 여수로의 마루를 따라 부압이 없었습니다. 여수로 끝단의 바닥 부근의 압력 결과는 평평하고 고인 경우 부압이 발생하지 않았음을 나타냅니다. 수직면 부근의 음압은 웅덩이에 비해 평평한 계단형 여수로의 깊이(w=0 cm)의 대부분에서 발생하였다. 또한 더 큰 사면에 대한 풀링 케이스에서 음압이 제거되었습니다. 평단식 여수로에서는 계단의 수직면에 인접한 더 넓은 지역에서 음압이 발생하였기 때문에 이 여수로에서는 고형단식여수로보다 캐비테이션 현상이 발생할 가능성이 더 큽니다.

    In this study, the FLOW-3D software was used through utilizing the VOF method and k −ε (RNG) turbulence model in order to simulate free surface, and turbulence characteristics for the purpose of simulating flow over pooled stepped spillway. The results obtained indicated that the numerical model properly simulated the inception point location, void fraction, and pressure. The height of the pools has the insignificant effect on the location of air entrainment, so that obtained results were in good agreement with the correlations presented in this paper. In other words, available correlations can be used for different pool heights. The results of void fraction showed that the void fraction values in nappe flow regime near the step pool were more than the other discharges. Furthermore in high discharge, 0.113m3/s, altering pool height had no effect on the value of void fraction near the pool surface.

    The effect of the pools with 0 and 3 cm heights over the pressure distribution in nappe and transition regimes was mostly similar in many points. Furthermore, in all examined heights there was no negative pressure along the crest of the spillway. The pressure results near the bed of the step at the end of the spillway indicated that negative pressure did not occur in the flat and pooled cases. Negative pressure near the vertical face occurred in the most part of the depth in the flat stepped spillway (w=0 cm) in comparison with the pooled case. Also, the negative pressure was eliminated in the pooled case for the larger slopes. Since negative pressure occurred in a larger area adjacent the vertical face of the steps in the flat stepped spillways, it is more likely that cavitation phenomenon occurs in this spillway rather than the pooled stepped spillways.

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    Optimization Algorithms and Engineering: Recent Advances and Applications

    Mahdi Feizbahr,1 Navid Tonekaboni,2Guang-Jun Jiang,3,4 and Hong-Xia Chen3,4Show moreAcademic Editor: Mohammad YazdiReceived08 Apr 2021Revised18 Jun 2021Accepted17 Jul 2021Published11 Aug 2021

    Abstract

    Vegetation along the river increases the roughness and reduces the average flow velocity, reduces flow energy, and changes the flow velocity profile in the cross section of the river. Many canals and rivers in nature are covered with vegetation during the floods. Canal’s roughness is strongly affected by plants and therefore it has a great effect on flow resistance during flood. Roughness resistance against the flow due to the plants depends on the flow conditions and plant, so the model should simulate the current velocity by considering the effects of velocity, depth of flow, and type of vegetation along the canal. Total of 48 models have been simulated to investigate the effect of roughness in the canal. The results indicated that, by enhancing the velocity, the effect of vegetation in decreasing the bed velocity is negligible, while when the current has lower speed, the effect of vegetation on decreasing the bed velocity is obviously considerable.


    강의 식생은 거칠기를 증가시키고 평균 유속을 감소시키며, 유속 에너지를 감소시키고 강의 단면에서 유속 프로파일을 변경합니다. 자연의 많은 운하와 강은 홍수 동안 초목으로 덮여 있습니다. 운하의 조도는 식물의 영향을 많이 받으므로 홍수시 유동저항에 큰 영향을 미칩니다. 식물로 인한 흐름에 대한 거칠기 저항은 흐름 조건 및 식물에 따라 다르므로 모델은 유속, 흐름 깊이 및 운하를 따라 식생 유형의 영향을 고려하여 현재 속도를 시뮬레이션해야 합니다. 근관의 거칠기의 영향을 조사하기 위해 총 48개의 모델이 시뮬레이션되었습니다. 결과는 유속을 높임으로써 유속을 감소시키는 식생의 영향은 무시할 수 있는 반면, 해류가 더 낮은 유속일 때 유속을 감소시키는 식생의 영향은 분명히 상당함을 나타냈다.

    1. Introduction

    Considering the impact of each variable is a very popular field within the analytical and statistical methods and intelligent systems [114]. This can help research for better modeling considering the relation of variables or interaction of them toward reaching a better condition for the objective function in control and engineering [1527]. Consequently, it is necessary to study the effects of the passive factors on the active domain [2836]. Because of the effect of vegetation on reducing the discharge capacity of rivers [37], pruning plants was necessary to improve the condition of rivers. One of the important effects of vegetation in river protection is the action of roots, which cause soil consolidation and soil structure improvement and, by enhancing the shear strength of soil, increase the resistance of canal walls against the erosive force of water. The outer limbs of the plant increase the roughness of the canal walls and reduce the flow velocity and deplete the flow energy in vicinity of the walls. Vegetation by reducing the shear stress of the canal bed reduces flood discharge and sedimentation in the intervals between vegetation and increases the stability of the walls [3841].

    One of the main factors influencing the speed, depth, and extent of flood in this method is Manning’s roughness coefficient. On the other hand, soil cover [42], especially vegetation, is one of the most determining factors in Manning’s roughness coefficient. Therefore, it is expected that those seasonal changes in the vegetation of the region will play an important role in the calculated value of Manning’s roughness coefficient and ultimately in predicting the flood wave behavior [4345]. The roughness caused by plants’ resistance to flood current depends on the flow and plant conditions. Flow conditions include depth and velocity of the plant, and plant conditions include plant type, hardness or flexibility, dimensions, density, and shape of the plant [46]. In general, the issue discussed in this research is the optimization of flood-induced flow in canals by considering the effect of vegetation-induced roughness. Therefore, the effect of plants on the roughness coefficient and canal transmission coefficient and in consequence the flow depth should be evaluated [4748].

    Current resistance is generally known by its roughness coefficient. The equation that is mainly used in this field is Manning equation. The ratio of shear velocity to average current velocity  is another form of current resistance. The reason for using the  ratio is that it is dimensionless and has a strong theoretical basis. The reason for using Manning roughness coefficient is its pervasiveness. According to Freeman et al. [49], the Manning roughness coefficient for plants was calculated according to the Kouwen and Unny [50] method for incremental resistance. This method involves increasing the roughness for various surface and plant irregularities. Manning’s roughness coefficient has all the factors affecting the resistance of the canal. Therefore, the appropriate way to more accurately estimate this coefficient is to know the factors affecting this coefficient [51].

    To calculate the flow rate, velocity, and depth of flow in canals as well as flood and sediment estimation, it is important to evaluate the flow resistance. To determine the flow resistance in open ducts, Manning, Chézy, and Darcy–Weisbach relations are used [52]. In these relations, there are parameters such as Manning’s roughness coefficient (n), Chézy roughness coefficient (C), and Darcy–Weisbach coefficient (f). All three of these coefficients are a kind of flow resistance coefficient that is widely used in the equations governing flow in rivers [53].

    The three relations that express the relationship between the average flow velocity (V) and the resistance and geometric and hydraulic coefficients of the canal are as follows:where nf, and c are Manning, Darcy–Weisbach, and Chézy coefficients, respectively. V = average flow velocity, R = hydraulic radius, Sf = slope of energy line, which in uniform flow is equal to the slope of the canal bed,  = gravitational acceleration, and Kn is a coefficient whose value is equal to 1 in the SI system and 1.486 in the English system. The coefficients of resistance in equations (1) to (3) are related as follows:

    Based on the boundary layer theory, the flow resistance for rough substrates is determined from the following general relation:where f = Darcy–Weisbach coefficient of friction, y = flow depth, Ks = bed roughness size, and A = constant coefficient.

    On the other hand, the relationship between the Darcy–Weisbach coefficient of friction and the shear velocity of the flow is as follows:

    By using equation (6), equation (5) is converted as follows:

    Investigation on the effect of vegetation arrangement on shear velocity of flow in laboratory conditions showed that, with increasing the shear Reynolds number (), the numerical value of the  ratio also increases; in other words the amount of roughness coefficient increases with a slight difference in the cases without vegetation, checkered arrangement, and cross arrangement, respectively [54].

    Roughness in river vegetation is simulated in mathematical models with a variable floor slope flume by different densities and discharges. The vegetation considered submerged in the bed of the flume. Results showed that, with increasing vegetation density, canal roughness and flow shear speed increase and with increasing flow rate and depth, Manning’s roughness coefficient decreases. Factors affecting the roughness caused by vegetation include the effect of plant density and arrangement on flow resistance, the effect of flow velocity on flow resistance, and the effect of depth [4555].

    One of the works that has been done on the effect of vegetation on the roughness coefficient is Darby [56] study, which investigates a flood wave model that considers all the effects of vegetation on the roughness coefficient. There are currently two methods for estimating vegetation roughness. One method is to add the thrust force effect to Manning’s equation [475758] and the other method is to increase the canal bed roughness (Manning-Strickler coefficient) [455961]. These two methods provide acceptable results in models designed to simulate floodplain flow. Wang et al. [62] simulate the floodplain with submerged vegetation using these two methods and to increase the accuracy of the results, they suggested using the effective height of the plant under running water instead of using the actual height of the plant. Freeman et al. [49] provided equations for determining the coefficient of vegetation roughness under different conditions. Lee et al. [63] proposed a method for calculating the Manning coefficient using the flow velocity ratio at different depths. Much research has been done on the Manning roughness coefficient in rivers, and researchers [496366] sought to obtain a specific number for n to use in river engineering. However, since the depth and geometric conditions of rivers are completely variable in different places, the values of Manning roughness coefficient have changed subsequently, and it has not been possible to choose a fixed number. In river engineering software, the Manning roughness coefficient is determined only for specific and constant conditions or normal flow. Lee et al. [63] stated that seasonal conditions, density, and type of vegetation should also be considered. Hydraulic roughness and Manning roughness coefficient n of the plant were obtained by estimating the total Manning roughness coefficient from the matching of the measured water surface curve and water surface height. The following equation is used for the flow surface curve:where  is the depth of water change, S0 is the slope of the canal floor, Sf is the slope of the energy line, and Fr is the Froude number which is obtained from the following equation:where D is the characteristic length of the canal. Flood flow velocity is one of the important parameters of flood waves, which is very important in calculating the water level profile and energy consumption. In the cases where there are many limitations for researchers due to the wide range of experimental dimensions and the variety of design parameters, the use of numerical methods that are able to estimate the rest of the unknown results with acceptable accuracy is economically justified.

    FLOW-3D software uses Finite Difference Method (FDM) for numerical solution of two-dimensional and three-dimensional flow. This software is dedicated to computational fluid dynamics (CFD) and is provided by Flow Science [67]. The flow is divided into networks with tubular cells. For each cell there are values of dependent variables and all variables are calculated in the center of the cell, except for the velocity, which is calculated at the center of the cell. In this software, two numerical techniques have been used for geometric simulation, FAVOR™ (Fractional-Area-Volume-Obstacle-Representation) and the VOF (Volume-of-Fluid) method. The equations used at this model for this research include the principle of mass survival and the magnitude of motion as follows. The fluid motion equations in three dimensions, including the Navier–Stokes equations with some additional terms, are as follows:where  are mass accelerations in the directions xyz and  are viscosity accelerations in the directions xyz and are obtained from the following equations:

    Shear stresses  in equation (11) are obtained from the following equations:

    The standard model is used for high Reynolds currents, but in this model, RNG theory allows the analytical differential formula to be used for the effective viscosity that occurs at low Reynolds numbers. Therefore, the RNG model can be used for low and high Reynolds currents.

    Weather changes are high and this affects many factors continuously. The presence of vegetation in any area reduces the velocity of surface flows and prevents soil erosion, so vegetation will have a significant impact on reducing destructive floods. One of the methods of erosion protection in floodplain watersheds is the use of biological methods. The presence of vegetation in watersheds reduces the flow rate during floods and prevents soil erosion. The external organs of plants increase the roughness and decrease the velocity of water flow and thus reduce its shear stress energy. One of the important factors with which the hydraulic resistance of plants is expressed is the roughness coefficient. Measuring the roughness coefficient of plants and investigating their effect on reducing velocity and shear stress of flow is of special importance.

    Roughness coefficients in canals are affected by two main factors, namely, flow conditions and vegetation characteristics [68]. So far, much research has been done on the effect of the roughness factor created by vegetation, but the issue of plant density has received less attention. For this purpose, this study was conducted to investigate the effect of vegetation density on flow velocity changes.

    In a study conducted using a software model on three density modes in the submerged state effect on flow velocity changes in 48 different modes was investigated (Table 1).Table 1 The studied models.

    The number of cells used in this simulation is equal to 1955888 cells. The boundary conditions were introduced to the model as a constant speed and depth (Figure 1). At the output boundary, due to the presence of supercritical current, no parameter for the current is considered. Absolute roughness for floors and walls was introduced to the model (Figure 1). In this case, the flow was assumed to be nonviscous and air entry into the flow was not considered. After  seconds, this model reached a convergence accuracy of .

    Figure 1 The simulated model and its boundary conditions.

    Due to the fact that it is not possible to model the vegetation in FLOW-3D software, in this research, the vegetation of small soft plants was studied so that Manning’s coefficients can be entered into the canal bed in the form of roughness coefficients obtained from the studies of Chow [69] in similar conditions. In practice, in such modeling, the effect of plant height is eliminated due to the small height of herbaceous plants, and modeling can provide relatively acceptable results in these conditions.

    48 models with input velocities proportional to the height of the regular semihexagonal canal were considered to create supercritical conditions. Manning coefficients were applied based on Chow [69] studies in order to control the canal bed. Speed profiles were drawn and discussed.

    Any control and simulation system has some inputs that we should determine to test any technology [7077]. Determination and true implementation of such parameters is one of the key steps of any simulation [237881] and computing procedure [8286]. The input current is created by applying the flow rate through the VFR (Volume Flow Rate) option and the output flow is considered Output and for other borders the Symmetry option is considered.

    Simulation of the models and checking their action and responses and observing how a process behaves is one of the accepted methods in engineering and science [8788]. For verification of FLOW-3D software, the results of computer simulations are compared with laboratory measurements and according to the values of computational error, convergence error, and the time required for convergence, the most appropriate option for real-time simulation is selected (Figures 2 and 3 ).

    Figure 2 Modeling the plant with cylindrical tubes at the bottom of the canal.

    Figure 3 Velocity profiles in positions 2 and 5.

    The canal is 7 meters long, 0.5 meters wide, and 0.8 meters deep. This test was used to validate the application of the software to predict the flow rate parameters. In this experiment, instead of using the plant, cylindrical pipes were used in the bottom of the canal.

    The conditions of this modeling are similar to the laboratory conditions and the boundary conditions used in the laboratory were used for numerical modeling. The critical flow enters the simulation model from the upstream boundary, so in the upstream boundary conditions, critical velocity and depth are considered. The flow at the downstream boundary is supercritical, so no parameters are applied to the downstream boundary.

    The software well predicts the process of changing the speed profile in the open canal along with the considered obstacles. The error in the calculated speed values can be due to the complexity of the flow and the interaction of the turbulence caused by the roughness of the floor with the turbulence caused by the three-dimensional cycles in the hydraulic jump. As a result, the software is able to predict the speed distribution in open canals.

    2. Modeling Results

    After analyzing the models, the results were shown in graphs (Figures 414 ). The total number of experiments in this study was 48 due to the limitations of modeling.(a)
    (a)(b)
    (b)(c)
    (c)(d)
    (d)(a)
    (a)(b)
    (b)(c)
    (c)(d)
    (d)Figure 4 Flow velocity profiles for canals with a depth of 1 m and flow velocities of 3–3.3 m/s. Canal with a depth of 1 meter and a flow velocity of (a) 3 meters per second, (b) 3.1 meters per second, (c) 3.2 meters per second, and (d) 3.3 meters per second.

    Figure 5 Canal diagram with a depth of 1 meter and a flow rate of 3 meters per second.

    Figure 6 Canal diagram with a depth of 1 meter and a flow rate of 3.1 meters per second.

    Figure 7 Canal diagram with a depth of 1 meter and a flow rate of 3.2 meters per second.

    Figure 8 Canal diagram with a depth of 1 meter and a flow rate of 3.3 meters per second.(a)
    (a)(b)
    (b)(c)
    (c)(d)
    (d)(a)
    (a)(b)
    (b)(c)
    (c)(d)
    (d)Figure 9 Flow velocity profiles for canals with a depth of 2 m and flow velocities of 4–4.3 m/s. Canal with a depth of 2 meters and a flow rate of (a) 4 meters per second, (b) 4.1 meters per second, (c) 4.2 meters per second, and (d) 4.3 meters per second.

    Figure 10 Canal diagram with a depth of 2 meters and a flow rate of 4 meters per second.

    Figure 11 Canal diagram with a depth of 2 meters and a flow rate of 4.1 meters per second.

    Figure 12 Canal diagram with a depth of 2 meters and a flow rate of 4.2 meters per second.

    Figure 13 Canal diagram with a depth of 2 meters and a flow rate of 4.3 meters per second.(a)
    (a)(b)
    (b)(c)
    (c)(d)
    (d)(a)
    (a)(b)
    (b)(c)
    (c)(d)
    (d)Figure 14 Flow velocity profiles for canals with a depth of 3 m and flow velocities of 5–5.3 m/s. Canal with a depth of 2 meters and a flow rate of (a) 4 meters per second, (b) 4.1 meters per second, (c) 4.2 meters per second, and (d) 4.3 meters per second.

    To investigate the effects of roughness with flow velocity, the trend of flow velocity changes at different depths and with supercritical flow to a Froude number proportional to the depth of the section has been obtained.

    According to the velocity profiles of Figure 5, it can be seen that, with the increasing of Manning’s coefficient, the canal bed speed decreases.

    According to Figures 5 to 8, it can be found that, with increasing the Manning’s coefficient, the canal bed speed decreases. But this deceleration is more noticeable than the deceleration of the models 1 to 12, which can be justified by increasing the speed and of course increasing the Froude number.

    According to Figure 10, we see that, with increasing Manning’s coefficient, the canal bed speed decreases.

    According to Figure 11, we see that, with increasing Manning’s coefficient, the canal bed speed decreases. But this deceleration is more noticeable than the deceleration of Figures 510, which can be justified by increasing the speed and, of course, increasing the Froude number.

    With increasing Manning’s coefficient, the canal bed speed decreases (Figure 12). But this deceleration is more noticeable than the deceleration of the higher models (Figures 58 and 1011), which can be justified by increasing the speed and, of course, increasing the Froude number.

    According to Figure 13, with increasing Manning’s coefficient, the canal bed speed decreases. But this deceleration is more noticeable than the deceleration of Figures 5 to 12, which can be justified by increasing the speed and, of course, increasing the Froude number.

    According to Figure 15, with increasing Manning’s coefficient, the canal bed speed decreases.

    Figure 15 Canal diagram with a depth of 3 meters and a flow rate of 5 meters per second.

    According to Figure 16, with increasing Manning’s coefficient, the canal bed speed decreases. But this deceleration is more noticeable than the deceleration of the higher model, which can be justified by increasing the speed and, of course, increasing the Froude number.

    Figure 16 Canal diagram with a depth of 3 meters and a flow rate of 5.1 meters per second.

    According to Figure 17, it is clear that, with increasing Manning’s coefficient, the canal bed speed decreases. But this deceleration is more noticeable than the deceleration of the higher models, which can be justified by increasing the speed and, of course, increasing the Froude number.

    Figure 17 Canal diagram with a depth of 3 meters and a flow rate of 5.2 meters per second.

    According to Figure 18, with increasing Manning’s coefficient, the canal bed speed decreases. But this deceleration is more noticeable than the deceleration of the higher models, which can be justified by increasing the speed and, of course, increasing the Froude number.

    Figure 18 Canal diagram with a depth of 3 meters and a flow rate of 5.3 meters per second.

    According to Figure 19, it can be seen that the vegetation placed in front of the flow input velocity has negligible effect on the reduction of velocity, which of course can be justified due to the flexibility of the vegetation. The only unusual thing is the unexpected decrease in floor speed of 3 m/s compared to higher speeds.(a)
    (a)(b)
    (b)(c)
    (c)(a)
    (a)(b)
    (b)(c)
    (c)Figure 19 Comparison of velocity profiles with the same plant densities (depth 1 m). Comparison of velocity profiles with (a) plant densities of 25%, depth 1 m; (b) plant densities of 50%, depth 1 m; and (c) plant densities of 75%, depth 1 m.

    According to Figure 20, by increasing the speed of vegetation, the effect of vegetation on reducing the flow rate becomes more noticeable. And the role of input current does not have much effect in reducing speed.(a)
    (a)(b)
    (b)(c)
    (c)(a)
    (a)(b)
    (b)(c)
    (c)Figure 20 Comparison of velocity profiles with the same plant densities (depth 2 m). Comparison of velocity profiles with (a) plant densities of 25%, depth 2 m; (b) plant densities of 50%, depth 2 m; and (c) plant densities of 75%, depth 2 m.

    According to Figure 21, it can be seen that, with increasing speed, the effect of vegetation on reducing the bed flow rate becomes more noticeable and the role of the input current does not have much effect. In general, it can be seen that, by increasing the speed of the input current, the slope of the profiles increases from the bed to the water surface and due to the fact that, in software, the roughness coefficient applies to the channel floor only in the boundary conditions, this can be perfectly justified. Of course, it can be noted that, due to the flexible conditions of the vegetation of the bed, this modeling can show acceptable results for such grasses in the canal floor. In the next directions, we may try application of swarm-based optimization methods for modeling and finding the most effective factors in this research [27815188994]. In future, we can also apply the simulation logic and software of this research for other domains such as power engineering [9599].(a)
    (a)(b)
    (b)(c)
    (c)(a)
    (a)(b)
    (b)(c)
    (c)Figure 21 Comparison of velocity profiles with the same plant densities (depth 3 m). Comparison of velocity profiles with (a) plant densities of 25%, depth 3 m; (b) plant densities of 50%, depth 3 m; and (c) plant densities of 75%, depth 3 m.

    3. Conclusion

    The effects of vegetation on the flood canal were investigated by numerical modeling with FLOW-3D software. After analyzing the results, the following conclusions were reached:(i)Increasing the density of vegetation reduces the velocity of the canal floor but has no effect on the velocity of the canal surface.(ii)Increasing the Froude number is directly related to increasing the speed of the canal floor.(iii)In the canal with a depth of one meter, a sudden increase in speed can be observed from the lowest speed and higher speed, which is justified by the sudden increase in Froude number.(iv)As the inlet flow rate increases, the slope of the profiles from the bed to the water surface increases.(v)By reducing the Froude number, the effect of vegetation on reducing the flow bed rate becomes more noticeable. And the input velocity in reducing the velocity of the canal floor does not have much effect.(vi)At a flow rate between 3 and 3.3 meters per second due to the shallow depth of the canal and the higher landing number a more critical area is observed in which the flow bed velocity in this area is between 2.86 and 3.1 m/s.(vii)Due to the critical flow velocity and the slight effect of the roughness of the horseshoe vortex floor, it is not visible and is only partially observed in models 1-2-3 and 21.(viii)As the flow rate increases, the effect of vegetation on the rate of bed reduction decreases.(ix)In conditions where less current intensity is passing, vegetation has a greater effect on reducing current intensity and energy consumption increases.(x)In the case of using the flow rate of 0.8 cubic meters per second, the velocity distribution and flow regime show about 20% more energy consumption than in the case of using the flow rate of 1.3 cubic meters per second.

    Nomenclature

    n:Manning’s roughness coefficient
    C:Chézy roughness coefficient
    f:Darcy–Weisbach coefficient
    V:Flow velocity
    R:Hydraulic radius
    g:Gravitational acceleration
    y:Flow depth
    Ks:Bed roughness
    A:Constant coefficient
    :Reynolds number
    y/∂x:Depth of water change
    S0:Slope of the canal floor
    Sf:Slope of energy line
    Fr:Froude number
    D:Characteristic length of the canal
    G:Mass acceleration
    :Shear stresses.

    Data Availability

    All data are included within the paper.

    Conflicts of Interest

    The authors declare that they have no conflicts of interest.

    Acknowledgments

    This work was partially supported by the National Natural Science Foundation of China under Contract no. 71761030 and Natural Science Foundation of Inner Mongolia under Contract no. 2019LH07003.

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    A 3-D numerical simulation of the characteristics of open channel flows with submerged rigid vegetation

    A 3-D numerical simulation of the characteristics of open channel flows with submerged rigid vegetation

    수중 강성 식생이 있는 개방 수로 흐름의 특성에 대한 3차원 수치 시뮬레이션

    Journal of Hydrodynamics (2021)Cite this article

    Abstract

    이 논문은 FLOW-3D를 적용하여 다양한 흐름 배출 및 식생 시나리오가 유속(종방향, 횡방향 및 수직 속도 포함)에 미치는 영향을 조사합니다.

    실험적 측정을 통한 검증 후 식생직경, 식생높이, 유출량에 대한 민감도 분석을 수행하였습니다. 종방향 속도의 경우 흐름 구조에 대한 가장 큰 영향은 배출보다는 식생 직경에서 비롯됩니다.

    그러나 식생 높이는 수직 분포의 변곡점을 결정합니다. 식생 지역, 즉 상류와 하류의 두 위치에서 횡단 속도를 비교하면 수심을 따라 대칭 패턴이 식별됩니다. 식생 지역의 횡단 및 수직 유체 순환 패턴을 포함하여 흐름 또는 식생 시나리오에 관계없이 수직 속도에서도 동일한 패턴이 관찰됩니다.

    또한 식생 직경이 클수록 이러한 패턴이 더 분명해집니다. 상부 순환은 식생 캐노피 근처에서 발생합니다. 식생 지역의 가로 세로 방향 순환에 관한 이러한 발견은 수중 식생을 통한 3차원 흐름 구조를 밝혀줍니다.

    This paper applies the Flow-3D to investigate the impacts of different flow discharge and vegetation scenarios on the flow velocity (including the longitudinal, transverse and vertical velocities). After the verification by using experimental measurements, a sensitivity analysis is conducted for the vegetation diameter, the vegetation height and the flow discharge. For the longitudinal velocity, the greatest impact on the flow structure originates from the vegetation diameter, rather than the discharge. The vegetation height, however, determines the inflection point of the vertical distribution. Comparing the transverse velocities at two positions in the vegetated area, i.e., the upstream and the downstream, a symmetric pattern is identified along the water depth. The same pattern is also observed for the vertical velocity regardless of the flow or vegetation scenario, including both transverse and vertical fluid circulation patterns in the vegetated area. Moreover, the larger the vegetation diameter is, the more evident these patterns become. The upper circulation occurs near the vegetation canopy. These findings regarding the circulations along the transverse and vertical directions in the vegetated region shed light on the 3-D flow structure through the submerged vegetation.

    Key words

    • Submerged rigid vegetation
    • longitudinal velocity
    • transverse velocity
    • vertical velocity

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    Fig. 1. Hydraulic jump flow structure.

    Performance assessment of OpenFOAM and FLOW-3D in the numerical modeling of a low Reynolds number hydraulic jump

    낮은 레이놀즈 수 유압 점프의 수치 모델링에서 OpenFOAM 및 FLOW-3D의 성능 평가

    ArnauBayona DanielValerob RafaelGarcía-Bartuala Francisco ​JoséVallés-Morána P. AmparoLópez-Jiméneza

    Abstract

    A comparative performance analysis of the CFD platforms OpenFOAM and FLOW-3D is presented, focusing on a 3D swirling turbulent flow: a steady hydraulic jump at low Reynolds number. Turbulence is treated using RANS approach RNG k-ε. A Volume Of Fluid (VOF) method is used to track the air–water interface, consequently aeration is modeled using an Eulerian–Eulerian approach. Structured meshes of cubic elements are used to discretize the channel geometry. The numerical model accuracy is assessed comparing representative hydraulic jump variables (sequent depth ratio, roller length, mean velocity profiles, velocity decay or free surface profile) to experimental data. The model results are also compared to previous studies to broaden the result validation. Both codes reproduced the phenomenon under study concurring with experimental data, although special care must be taken when swirling flows occur. Both models can be used to reproduce the hydraulic performance of energy dissipation structures at low Reynolds numbers.

    CFD 플랫폼 OpenFOAM 및 FLOW-3D의 비교 성능 분석이 3D 소용돌이치는 난류인 낮은 레이놀즈 수에서 안정적인 유압 점프에 초점을 맞춰 제시됩니다. 난류는 RANS 접근법 RNG k-ε을 사용하여 처리됩니다.

    VOF(Volume Of Fluid) 방법은 공기-물 계면을 추적하는 데 사용되며 결과적으로 Eulerian-Eulerian 접근 방식을 사용하여 폭기가 모델링됩니다. 입방체 요소의 구조화된 메쉬는 채널 형상을 이산화하는 데 사용됩니다. 수치 모델 정확도는 대표적인 유압 점프 변수(연속 깊이 비율, 롤러 길이, 평균 속도 프로파일, 속도 감쇠 또는 자유 표면 프로파일)를 실험 데이터와 비교하여 평가됩니다.

    모델 결과는 또한 결과 검증을 확장하기 위해 이전 연구와 비교됩니다. 소용돌이 흐름이 발생할 때 특별한 주의가 필요하지만 두 코드 모두 실험 데이터와 일치하는 연구 중인 현상을 재현했습니다. 두 모델 모두 낮은 레이놀즈 수에서 에너지 소산 구조의 수리 성능을 재현하는 데 사용할 수 있습니다.

    Keywords

    CFDRANS, OpenFOAM, FLOW-3D ,Hydraulic jump, Air–water flow, Low Reynolds number

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    The Optimal Operation on Auxiliary Spillway to Minimize the Flood Damage in Downstream River with Various Outflow Conditions

    류하천의 영향 최소화를 위한 보조 여수로 최적 활용방안 검토

    Hyung Ju Yoo1 Sung Sik Joo2 Beom Jae Kwon3 Seung Oh Lee4*
    유 형주1 주 성식2 권 범재3 이 승오4*
    1Ph.D Student, Dept. of Civil & Environmental Engineering, Hongik University2Director, Water Resources & Environment Department, HECOREA3Director, Water Resources Department, ISAN4Professor, Dept. of Civil & Environmental Engineering, Hongik University
    1홍익대학교 건설환경공학과 박사과정
    2㈜헥코리아 수자원환경사업부 이사
    3㈜이산 수자원부 이사
    4홍익대학교 건설환경공학과 교수*Corresponding Author

    ABSTRACT

    최근 기후변화로 인해 강우강도 및 빈도의 증가에 따른 집중호우의 영향 및 기존 여수로의 노후화에 대비하여 홍수 시 하류 하천의 영향을 최소화할 수 있는 보조 여수로 활용방안 구축이 필요한 실정이다. 이를 위해, 수리모형 실험 및 수치모형 실험을 통하여 보조 여수로 운영에 따른 흐름특성 변화 검토에 관한 연구가 많이 진행되어 왔다.

    그러나 대부분의 연구는 여수로에서의 흐름특성 및 기능성에 대한 검토를 수행하였을 뿐 보조 여수로의 활용방안에 따른 하류하천 영향 검토 및 호안 안정성 검토에 관한 연구는 미비한 실정이다.

    이에 본 연구에서는 기존 여수로 및 보조 여수로 방류 조건에 따른 하류영향 분석 및 호안 안정성 측면에서 최적 방류 시나리오 검토를 3차원 수치모형인 FLOW-3D를 사용하여 검토하였다. 또한 FLOW-3D 수치모의 수행을 통한 유속, 수위 결과와 소류력 산정 결과를 호안 설계허용 기준과 비교하였다.

    수문 완전 개도 조건으로 가정하고 계획홍수량 유입 시 다양한 보조 여수로 활용방안에 대하여 수치모의를 수행한 결과, 보조 여수로 단독 운영 시 기존 여수로 단독운영에 비하여 최대유속 및 최대 수위의 감소효과를 확인하였다. 다만 계획홍수량의 45% 이하 방류 조건에서 대안부의 호안 안정성을 확보하였고 해당 방류량 초과 경우에는 처오름 현상이 발생하여 월류에 대한 위험성 증가를 확인하였다.

    따라서 기존 여수로와의 동시 운영 방안 도출이 중요하다고 판단하였다. 여수로의 배분 비율 및 총 허용 방류량에 대하여 검토한 결과 보조 여수로의 방류량이 기존 여수로의 방류량보다 큰 경우 하류하천의 흐름이 중심으로 집중되어 대안부의 유속 저감 및 수위 감소를 확인하였고, 계획 홍수량의 77% 이하의 조건에서 호안의 허용 유속 및 허용 소류력 조건을 만족하였다.

    이를 통하여 본 연구에서 제안한 보조 여수로 활용방안으로는 기존 여수로와 동시 운영 시 총 방류량에 대하여 보조 여수로의 배분량이 기존 여수로의 배분량보다 크게 설정하는 것이 하류하천의 영향을 최소화 할 수 있는 것으로 나타났다.

    그러나 본 연구는 여수로 방류에 따른 대안부에서의 영향에 대해서만 검토하였고 수문 전면 개도 조건에서 검토하였다는 한계점은 분명히 있다. 이에 향후에는 다양한 수문 개도 조건 및 방류 시나리오를 적용 및 검토한다면 보다 효율적이고, 효과적인 보조 여수로 활용방안을 도출이 가능할 것으로 기대 된다.

    키워드

    보조 여수로, FLOW-3D, 수치모의, 호안 안정성, 소류력

    Recently, as the occurrence frequency of sudden floods due to climate change increased and the aging of the existing spillway, it is necessary to establish a plan to utilize an auxiliary spillway to minimize the flood damage of downstream rivers. Most studies have been conducted on the review of flow characteristics according to the operation of auxiliary spillway through the hydraulic experiments and numerical modeling. However, the studies on examination of flood damage in the downstream rivers and the stability of the revetment according to the operation of the auxiliary spillway were relatively insufficient in the literature. In this study, the stability of the revetment on the downstream river according to the outflow conditions of the existing and auxiliary spillway was examined by using 3D numerical model, FLOW-3D. The velocity, water surface elevation and shear stress results of FLOW-3D were compared with the permissible velocity and shear stress of design criteria. It was assumed the sluice gate was fully opened. As a result of numerical simulations of various auxiliary spillway operations during flood season, the single operation of the auxiliary spillway showed the reduction effect of maximum velocity and the water surface elevation compared with the single operation of the existing spillway. The stability of the revetment on downstream was satisfied under the condition of outflow less than 45% of the design flood discharge. However, the potential overtopping damage was confirmed in the case of exceeding the 45% of the design flood discharge. Therefore, the simultaneous operation with the existing spillway was important to ensure the stability on design flood discharge condition. As a result of examining the allocation ratio and the total allowable outflow, the reduction effect of maximum velocity was confirmed on the condition, where the amount of outflow on auxiliary spillway was more than that on existing spillway. It is because the flow of downstream rivers was concentrated in the center due to the outflow of existing spillway. The permissible velocity and shear stress were satisfied under the condition of less than 77% of the design flood discharge with simultaneous operation. It was found that the flood damage of downstream rivers can be minimized by setting the amount allocated to the auxiliary spillway to be larger than the amount allocated to the existing spillway for the total outflow with simultaneous operation condition. However, this study only reviewed the flow characteristics around the revetment according to the outflow of spillway under the full opening of the sluice gate condition. Therefore, the various sluice opening conditions and outflow scenarios will be asked to derive more efficient utilization of the auxiliary spillway in th future.KeywordsAuxiliary spillway FLOW-3D Numerical simulation Revetment stability Shear stress

    1. 서 론

    최근 기후변화로 인한 집중호우의 영향으로 홍수 시 댐으로 유입되는 홍수량이 설계 홍수량보다 증가하여 댐 안정성 확보가 필요한 실정이다(Office for Government Policy Coordination, 2003). MOLIT & K-water(2004)에서는 기존댐의 수문학적 안정성 검토를 수행하였으며 이상홍수 발생 시 24개 댐에서 월류 등으로 인한 붕괴위험으로 댐 하류지역의 극심한 피해를 예상하여 보조여수로 신설 및 기존여수로 확장 등 치수능력 증대 기본계획을 수립하였고 이를 통하여 극한홍수 발생 시 홍수량 배제능력을 증대하여 기존댐의 안전성 확보 및 하류지역의 피해를 방지하고자 하였다. 여기서 보조 여수로는 기존 여수로와 동시 또는 별도 운영하는 여수로로써 비상상황 시 방류 기능을 포함하고 있고(K-water, 2021), 최근에는 기존 여수로의 노후화에 따라 보조여수로의 활용방안에 대한 관심이 증가하고 있다. 따라서 본 연구에서는 3차원 수치해석을 수행하여 기존 및 보조 여수로의 방류량 조합에 따른 하류 영향을 분석하고 하류 호안 안정성 측면에서 최적 방류 시나리오를 검토하고자 한다.

    기존의 댐 여수로 검토에 관한 연구는 주로 수리실험을 통하여 방류조건 별 흐름특성을 검토하였으나 최근에는 수치모형 실험결과가 수리모형실험과 비교하여 근사한 것을 확인하는 등 점차 수치모형실험을 수리모형실험의 대안으로 활용하고 있다(Jeon et al., 2006Kim, 2007Kim et al., 2008). 국내의 경우, Jeon et al.(2006)은 수리모형 실험과 수치모의를 이용하여 임하댐 바상여수로의 기본설계안을 도출하였고, Kim et al.(2008)은 가능최대홍수량 유입 시 비상여수로 방류에 따른 수리학적 안정성과 기능성을 3차원 수치모형인 FLOW-3D를 활용하여 검토하였다. 또한 Kim and Kim(2013)은 충주댐의 홍수조절 효과 검토 및 방류량 변화에 따른 상·하류의 수위 변화를 수치모형을 통하여 검토하였다. 국외의 경우 Zeng et al.(2017)은 3차원 수치모형인 Fluent를 활용한 여수로 방류에 따른 흐름특성 결과와 측정결과를 비교하여 수치모형 결과의 신뢰성을 검토하였다. Li et al.(2011)은 가능 최대 홍수량(Probable Maximum Flood, PMF)조건에서 기존 여수로와 신규 보조 여수로 유입부 주변의 흐름특성에 대하여 3차원 수치모형 Fluent를 활용하여 검토하였고, Lee et al.(2019)는 서로 근접해있는 기존 여수로와 보조여수로 동시 운영 시 방류능 검토를 수리모형 실험 및 수치모형 실험(FLOW-3D)을 통하여 수행하였으며 기존 여수로와 보조 여수로를 동시운영하게 되면 배수로 간섭으로 인하여 총 방류량이 7.6%까지 감소되어 댐의 방류능력이 감소하였음을 확인하였다.

    그러나 대부분의 여수로 검토에 대한 연구는 여수로 내에서의 흐름특성 및 기능성에 대한 검토를 수행하였고. 이에 기존 여수로와 보조 여수로 방류운영에 따른 하류하천의 흐름특성 변화 및 호안 안정성 평가에 관한 추가적인 검토가 필요한 실정이다. 따라서 본 연구에서는 기존 여수로 및 보조 여수로 방류 조건에 따른 하류하천의 흐름특성 및 호안 안정성분석을 3차원 수치모형인 FLOW-3D를 이용하여 검토하였다. 또한 다양한 방류 배분 비율 및 허용 방류량 조건 변화에 따른 하류하천의 흐름특성 및 소류력 분석결과를 호안 설계 허용유속 및 허용 소류력 기준과 비교하여 하류하천의 영향을 최소화 할 수 있는 최적의 보조 여수로 활용방안을 도출하고자 한다.

    2. 본 론

    2.1 이론적 배경

    2.1.1 3차원 수치모형의 기본이론

    FLOW-3D는 미국 Flow Science, Inc에서 개발한 범용 유체역학 프로그램(CFD, Computational Fluid Dynamics)으로 자유 수면을 갖는 흐름모의에 사용되는 3차원 수치해석 모형이다. 난류모형을 통해 난류 해석이 가능하고, 댐 방류에 따른 하류 하천의 흐름 해석에도 많이 사용되어 왔다(Flow Science, 2011). 본 연구에서는 FLOW-3D(version 12.0)을 이용하여 홍수 시 기존 여수로의 노후화에 대비하여 보조 여수로의 활용방안에 대한 검토를 하류하천의 호안 안정성 측면에서 검토하였다.

    2.1.2 유동해석의 지배방정식

    1) 연속 방정식(Continuity Equation)

    FLOW-3D는 비압축성 유체에 대하여 연속방정식을 사용하며, 밀도는 상수항으로 적용된다. 연속 방정식은 Eqs. (1)(2)와 같다.

    (1)

    ∇·v=0

    (2)

    ∂∂x(uAx)+∂∂y(vAy)+∂∂z(wAz)=RSORρ

    여기서, ρ는 유체 밀도(kg/m3), u, v, w는 x, y, z방향의 유속(m/s), Ax, Ay, Az는 각 방향의 요소면적(m2), RSOR는 질량 생성/소멸(mass source/sink)항을 의미한다.

    2) 운동량 방정식(Momentum Equation)

    각 방향 속도성분 u, v, w에 대한 운동방정식은 Navier-Stokes 방정식으로 다음 Eqs. (3)(4)(5)와 같다.

    (3)

    ∂u∂t+1VF(uAx∂u∂x+vAy∂v∂y+wAz∂w∂z)=-1ρ∂p∂x+Gx+fx-bx-RSORρVFu

    (4)

    ∂v∂t+1VF(uAx∂u∂x+vAy∂v∂y+wAz∂w∂z)=-1ρ∂p∂y+Gy+fy-by-RSORρVFv

    (5)

    ∂w∂t+1VF(uAx∂u∂x+vAy∂v∂y+wAz∂w∂z)=-1ρ∂p∂z+Gz+fz-bz-RSORρVFw

    여기서, Gx, Gy, Gz는 체적력에 의한 가속항, fx, fy, fz는 점성에 의한 가속항, bx, by, bz는 다공성 매체에서의 흐름손실을 의미한다.

    2.1.3 소류력 산정

    호안설계 시 제방사면 호안의 안정성 확보를 위해서는 하천의 흐름에 의하여 호안에 작용하는 소류력에 저항할 수 있는 재료 및 공법 선택이 필요하다. 국내의 경우 하천공사설계실무요령(MOLIT, 2016)에서 계획홍수량 유하 시 소류력 산정 방법을 제시하고 있다. 소류력은 하천의 평균유속을 이용하여 산정할 수 있으며, 소류력 산정식은 Eqs. (6)(7)과 같다.

    1) Schoklitsch 공식

    Schoklitsch(1934)는 Chezy 유속계수를 적용하여 소류력을 산정하였다.

    (6)

    τ=γRI=γC2V2

    여기서, τ는 소류력(N/m2), R은 동수반경(m), γ는 물의 단위중량(10.0 kN/m3), I는 에너지경사, C는 Chezy 유속계수, V는 평균유속(m/s)을 의미한다.

    2) Manning 조도계수를 고려한 공식

    Chezy 유속계수를 대신하여 Manning의 조도계수를 고려하여 소류력을 산정할 수 있다.

    (7)

    τ=γn2V2R1/3

    여기서, τ는 소류력(N/m2), R은 동수반경(m), γ는 물의 단위중량(10.0 kN/m3), n은 Manning의 조도계수, V는 평균유속(m/s)을 의미한다.

    FLOW-3D 수치모의 수행을 통하여 하천의 바닥 유속을 도출할 수 있으며, 본 연구에서는 Maning 조도계수롤 고려하여 소류력을 산정하고자 한다. 소류력을 산정하기 위해서 여수로 방류에 따른 대안부의 바닥유속 변화를 검토하여 최대 유속 값을 이용하였다. 최종적으로 산정한 소류력과 호안의 재료 및 공법에 따른 허용 소류력과 비교하여 제방사면 호안의 안정성 검토를 수행하게 된다.

    2.2 하천호안 설계기준

    하천 호안은 계획홍수위 이하의 유수작용에 대하여 안정성이 확보되도록 계획하여야 하며, 호안의 설계 시에는 사용재료의 확보용이성, 시공상의 용이성, 세굴에 대한 굴요성(flexibility) 등을 고려하여 호안의 형태, 시공방법 등을 결정한다(MOLIT, 2019). 국내의 경우, 하천공사설계실무요령(MOLIT, 2016)에서는 다양한 호안공법에 대하여 비탈경사에 따라 설계 유속을 비교하거나, 허용 소류력을 비교함으로써 호안의 안정성을 평가한다. 호안에 대한 국외의 설계기준으로 미국의 경우, ASTM(미국재료시험학회)에서 호안블록 및 식생매트 시험방법을 제시하였고 제품별로 ASTM 시험에 의한 허용유속 및 허용 소류력을 제시하였다. 일본의 경우, 호안 블록에 대한 축소실험을 통하여 항력을 측정하고 이를 통해서 호안 블록에 대한 항력계수를 제시하고 있다. 설계 시에는 항력계수에 의한 블록의 안정성을 평가하고 있으나, 최근에는 세굴의 영향을 고려할 수 있는 호안 안정성 평가의 필요성을 제기하고 있다(MOLIT, 2019). 관련된 국내·외의 하천호안 설계기준은 Table 1에 정리하여 제시하였고, 본 연구에서 하천 호안 안정성 평가 시 하천공사설계실무요령(MOLIT, 2016)과 ASTM 시험에서 제시한 허용소류력 및 허용유속 기준을 비교하여 각각 0.28 kN/m2, 5.0 m/s 미만일 경우 호안 안정성을 확보하였다고 판단하였다.

    Table 1.

    Standard of Permissible Velocity and Shear on Revetment

    Country (Reference)MaterialPermissible velocity (Vp, m/s)Permissible Shear (τp, kN/m2)
    KoreaRiver Construction Design Practice Guidelines
    (MOLIT, 2016)
    Vegetated5.00.50
    Stone5.00.80
    USAASTM D’6460Vegetated6.10.81
    Unvegetated5.00.28
    JAPANDynamic Design Method of Revetment5.0

    2.3. 보조여수로 운영에 따른 하류하천 영향 분석

    2.3.1 모형의 구축 및 경계조건

    본 연구에서는 기존 여수로의 노후화에 대비하여 홍수 시 보조여수로의 활용방안에 따른 하류하천의 흐름특성 및 호안안정성 평가를 수행하기 위해 FLOW-3D 모형을 이용하였다. 기존 여수로 및 보조 여수로는 치수능력 증대사업(MOLIT & K-water, 2004)을 통하여 완공된 ○○댐의 제원을 이용하여 구축하였다. ○○댐은 설계빈도(100년) 및 200년빈도 까지는 계획홍수위 이내로 기존 여수로를 통하여 운영이 가능하나 그 이상 홍수조절은 보조여수로를 통하여 조절해야 하며, 또한 2011년 기존 여수로 정밀안전진단 결과 사면의 표층 유실 및 옹벽 밀림현상 등이 확인되어 노후화에 따른 보수·보강이 필요한 상태이다. 이에 보조여수로의 활용방안 검토가 필요한 것으로 판단하여 본 연구의 대상댐으로 선정하였다. 하류 하천의 흐름특성을 예측하기 위하여 격자간격을 0.99 ~ 8.16 m의 크기로 하여 총 격자수는 49,102,500개로 구성하였으며, 여수로 방류에 따른 하류하천의 흐름해석을 위한 경계조건으로 상류는 유입유량(inflow), 바닥은 벽면(wall), 하류는 수위(water surface elevation)조건으로 적용하도록 하였다(Table 2Fig. 1 참조). FLOW-3D 난류모형에는 혼합길이 모형, 난류에너지 모형, k-ϵ모형, RNG(Renormalized Group Theory) k-ϵ모형, LES 모형 등이 있으며, 본 연구에서는 여수로 방류에 따른 복잡한 난류 흐름 및 높은 전단흐름을 정확하게 모의(Flow Science, 2011)할 수 있는 RNG k-ϵ모형을 사용하였고, 하류하천 호안의 안정성 측면에서 보조여수로의 활용방안을 검토하기 위하여 방류시나리오는 Table 3에 제시된 것 같이 설정하였다. Case 1 및 Case 2를 통하여 계획홍수량에 대하여 기존 여수로와 보조 여수로의 단독 운영이 하류하천에 미치는 영향을 확인하였고 보조 여수로의 방류량 조절을 통하여 호안 안정성 측면에서 보조 여수로 방류능 검토를 수행하였다(Case 3 ~ Case 6). 또한 기존 여수로와 보조 여수로의 방류량 배분에 따른 하류하천의 영향 검토(Case 7 ~ Case 10) 및 방류 배분에 따른 허용 방류량을 호안 안정성 측면에서 검토를 수행하였다(Case 11 ~ Case 14).

    수문은 완전개도 조건으로 가정하였으며 하류하천의 계획홍수량에 대한 기존 여수로와 보조여수로의 배분량을 조절하여 모의를 수행하였다. 여수로는 콘크리트의 조도계수 값(Chow, 1959)을 채택하였고, 댐 하류하천의 조도계수는 하천기본계획(Busan Construction and Management Administration, 2009) 제시된 조도계수 값을 채택하였으며 FLOW-3D의 적용을 위하여 Manning-Strickler 공식(Vanoni, 2006)을 이용하여 조도계수를 조고값으로 변환하여 사용하였다. Manning-Strickler 공식은 Eq. (8)과 같으며, FLOW-3D에 적용한 조도계수 및 조고는 Table 4와 같다.

    (8)

    n=ks1/68.1g1/2

    여기서, kS는 조고 (m), n은 Manning의 조도계수, g는 중력가속도(m/s2)를 의미한다.

    시간에 따라 동일한 유량이 일정하게 유입되도록 모의를 수행하였으며, 시간간격(Time Step)은 0.0001초로 설정(CFL number < 1.0) 하였다. 또한 여수로 수문을 통한 유량의 변동 값이 1.0%이내일 경우는 연속방정식을 만족하고 있다고 가정하였다. 이는, 유량의 변동 값이 1.0%이내일 경우 유속의 변동 값 역시 1.0%이내이며, 수치모의 결과 1.0%의 유속변동은 호안의 유속설계기준에 크게 영향을 미치지 않는다고 판단하였다. 그 결과 모든 수치모의 Case에서 2400초 이내에 결과 값이 수렴하는 것을 확인하였다.

    Table 2.

    Mesh sizes and numerical conditions

    MeshNumbers49,102,500 EA
    Increment (m)DirectionExisting SpillwayAuxiliary Spillway
    ∆X0.99 ~ 4.301.00 ~ 4.30
    ∆Y0.99 ~ 8.161.00 ~ 5.90
    ∆Z0.50 ~ 1.220.50 ~ 2.00
    Boundary ConditionsXmin / YmaxInflow / Water Surface Elevation
    Xmax, Ymin, Zmin / ZmaxWall / Symmetry
    Turbulence ModelRNG model
    Table 3.

    Case of numerical simulation (Qp : Design flood discharge)

    CaseExisting Spillway (Qe, m3/s)Auxiliary Spillway (Qa, m3/s)Remarks
    1Qp0Reference case
    20Qp
    300.58QpReview of discharge capacity on
    auxiliary spillway
    400.48Qp
    500.45Qp
    600.32Qp
    70.50Qp0.50QpDetermination of optimal division
    ratio on Spillways
    80.61Qp0.39Qp
    90.39Qp0.61Qp
    100.42Qp0.58Qp
    110.32Qp0.45QpDetermination of permissible
    division on Spillways
    120.35Qp0.48Qp
    130.38Qp0.53Qp
    140.41Qp0.56Qp
    Table 4.

    Roughness coefficient and roughness height

    CriteriaRoughness coefficient (n)Roughness height (ks, m)
    Structure (Concrete)0.0140.00061
    River0.0330.10496
    /media/sites/ksds/2021-014-02/N0240140207/images/ksds_14_02_07_F1.jpg
    Fig. 1

    Layout of spillway and river in this study

    2.3.2 보조 여수로의 방류능 검토

    본 연구에서는 기존 여수로와 보조 여수로의 방류량 배분에 따른 하류하천 대안부의 유속분포 및 수위분포를 검토하기 위해 수치모의 Case 별 다음과 같이 관심구역을 설정하였다(Fig. 2 참조). 관심구역(대안부)의 길이(L)는 총 1.3 km로 10 m 등 간격으로 나누어 검토하였으며, Section 1(0 < X/L < 0.27)은 기존 여수로 방류에 따른 영향이 지배적인 구간, Section 2(0.27 < X/L < 1.00)는 보조 여수로 방류에 따른 영향이 지배적인 구간으로 각 구간에서의 수위, 유속, 수심결과를 확인하였다. 기존 여수로의 노후화에 따른 보조 여수로의 방류능 검토를 위하여 Case 1 – Case 6까지의 결과를 비교하였다.

    보조 여수로의 단독 운영 시 기존 여수로 운영 시 보다 하류하천의 대안부의 최대 유속(Vmax)은 약 3% 감소하였으며, 이는 보조 여수로의 하천 유입각이 기존 여수로 보다 7°작으며 유입하천의 폭이 증가하여 유속이 감소한 것으로 판단된다. 대안부의 최대 유속 발생위치는 하류 쪽으로 이동하였으며 교량으로 인한 단면의 축소로 최대유속이 발생하는 것으로 판단된다. 또한 보조 여수로의 배분량(Qa)이 증가함에 따라 하류하천 대안부의 최대 유속이 증가하였다. 하천호안 설계기준에서 제시하고 있는 허용유속(Vp)과 비교한 결과, 계획홍수량(Qp)의 45% 이하(Case 5 & 6)를 보조 여수로에서 방류하게 되면 허용 유속(5.0 m/s)조건을 만족하여 호안안정성을 확보하였다(Fig. 3 참조). 허용유속 외에도 대안부에서의 소류력을 산정하여 하천호안 설계기준에서 제시한 허용 소류력(τp)과 비교한 결과, 유속과 동일하게 보조 여수로의 방류량이 계획홍수량의 45% 이하일 경우 허용소류력(0.28 kN/m2) 조건을 만족하였다(Fig. 4 참조). 각 Case 별 호안설계조건과 비교한 결과는 Table 5에 제시하였다.

    하류하천의 수위도 기존 여수로 운영 시 보다 보조 여수로 단독 운영 시 최대 수위(ηmax)가 약 2% 감소하는 효과를 보였으며 최대 수위 발생위치는 수충부로 여수로 방류시 처오름에 의한 수위 상승으로 판단된다. 기존 여수로의 단독운영(Case 1)의 수위(ηref)를 기준으로 보조 여수로의 방류량이 증가함에 따라 수위는 증가하였으나 계획홍수량의 58%까지 방류할 경우 월류에 대한 안정성(ηmax/ηref<0.97(=기설제방고))은 확보되었다(Fig. 5 참조). 그러나 계획홍수량 조건에서는 월류에 대한 위험성이 존재하기 때문에 기존여수로와 보조여수로의 적절한 방류량 배분 조합을 도출하는 것이 중요하다고 판단되어 진다.

    /media/sites/ksds/2021-014-02/N0240140207/images/ksds_14_02_07_F2.jpg
    Fig. 2

    Region of interest in this study

    /media/sites/ksds/2021-014-02/N0240140207/images/ksds_14_02_07_F3.jpg
    Fig. 3

    Maximum velocity and location of Vmax according to Qa

    /media/sites/ksds/2021-014-02/N0240140207/images/ksds_14_02_07_F4.jpg
    Fig. 4

    Maximum shear according to Qa

    /media/sites/ksds/2021-014-02/N0240140207/images/ksds_14_02_07_F5.jpg
    Fig. 5

    Maximum water surface elevation and location of ηmax according to Qa

    Table 5.

    Numerical results for each cases (Case 1 ~ Case 6)

    CaseMaximum Velocity
    (Vmax, m/s)
    Maximum Shear
    (τmax, kN/m2)
    Evaluation
    in terms of Vp
    Evaluation
    in terms of τp
    1
    (Qa = 0)
    9.150.54No GoodNo Good
    2
    (Qa = Qp)
    8.870.56No GoodNo Good
    3
    (Qa = 0.58Qp)
    6.530.40No GoodNo Good
    4
    (Qa = 0.48Qp)
    6.220.36No GoodNo Good
    5
    (Qa = 0.45Qp)
    4.220.12AccpetAccpet
    6
    (Qa = 0.32Qp)
    4.040.14AccpetAccpet

    2.3.3 기존 여수로와 보조 여수로 방류량 배분 검토

    기존 여수로 및 보조 여수로 단독운영에 따른 하류하천 및 호안의 안정성 평가를 수행한 결과 계획홍수량 방류 시 하류하천 대안부에서 호안 설계 조건(허용유속 및 허용 소류력)을 초과하였으며, 처오름에 의한 수위 상승으로 월류에 대한 위험성 증가를 확인하였다. 따라서 계획 홍수량 조건에서 기존 여수로와 보조 여수로의 방류량 배분을 통하여 호안 안정성을 확보하고 하류하천에 방류로 인한 피해를 최소화할 수 있는 배분조합(Case 7 ~ Case 10)을 검토하였다. Case 7은 기존 여수로와 보조여수로의 배분 비율을 균등하게 적용한 경우이고, Case 8은 기존 여수로의 배분량이 보조 여수로에 비하여 많은 경우, Case 9는 보조 여수로의 배분량이 기존 여수로에 비하여 많은 경우를 의미한다. 최대유속을 비교한 결과 보조 여수로의 배분 비율이 큰 경우 기존 여수로의 배분량에 의하여 흐름이 하천 중심에 집중되어 대안부의 유속을 저감하는 효과를 확인하였다. 보조여수로의 방류량 배분 비율이 증가할수록 기존 여수로 대안부 측(0.00<X/L<0.27, Section 1) 유속 분포는 감소하였으나, 신규여수로 대안부 측(0.27<X/L<1.00, Section 2) 유속은 증가하는 것을 확인하였다(Fig. 6 참조). 그러나 유속 저감 효과에도 대안부 전구간에서 설계 허용유속 조건을 초과하여 제방의 안정성을 확보하지는 못하였다. 소류력 산정 결과 유속과 동일하게 보조 여수로의 방류량이 기존 여수로의 방류량 보다 크면 감소하는 것을 확인하였고 일부 구간에서는 허용 소류력 조건을 만족하는 것을 확인하였다(Fig. 7 참조).

    따라서 유속 저감효과가 있는 배분 비율 조건(Qa>Qe)에서 Section 2에 유속 저감에 영향을 미치는 기존 여수로 방류량 배분 비율을 증가시켜 추가 검토(Case 10)를 수행하였다. 단독운영과 비교 시 하류하천에 유입되는 유량은 증가하였음에도 불구하고 기존 여수로 방류량에 의해 흐름이 하천 중심으로 집중되는 현상에 따라 대안부의 유속은 단독 운영에 비하여 감소하는 것을 확인하였고(Fig. 8 참조), 호안 설계 허용유속 및 허용 소류력 조건을 만족하는 구간이 발생하여 호안 안정성도 확보한 것으로 판단되었다. 최종적으로 각 Case 별 수위 결과의 경우 여수로 동시 운영을 수행하게 되면 대안부 전 구간에서 월류에 대한 안정성(ηmax/ηref<0.97(=기설제방고))은 확보하였다(Fig. 9 참조). 각 Case 별 대안부에서 최대 유속결과 및 산정한 소류력은 Table 6에 제시하였다.

    /media/sites/ksds/2021-014-02/N0240140207/images/ksds_14_02_07_F6.jpg
    Fig. 6

    Maximum velocity on section 1 & 2 according to Qa

    /media/sites/ksds/2021-014-02/N0240140207/images/ksds_14_02_07_F7.jpg
    Fig. 7

    Maximum shear on section 1 & 2 according to Qa

    /media/sites/ksds/2021-014-02/N0240140207/images/ksds_14_02_07_F8.jpg
    Fig. 8

    Velocity results of FLOW-3D (a: auxiliary spillway operation only , b : simultaneous operation of spillways)

    /media/sites/ksds/2021-014-02/N0240140207/images/ksds_14_02_07_F9.jpg
    Fig. 9

    Maximum water surface elevation on section 1 & 2 according to Qa

    Table 6.

    Numerical results for each cases (Case 7 ~ Case 10)

    Case (Qe &amp; Qa)Maximum Velocity (Vmax, m/s)Maximum Shear
    (τmax, kN/m2)
    Evaluation in terms of VpEvaluation in terms of τp
    Section 1Section 2Section 1Section 2Section 1Section 2Section 1Section 2
    7
    Qe : 0.50QpQa : 0.50Qp
    8.106.230.640.30No GoodNo GoodNo GoodNo Good
    8
    Qe : 0.61QpQa : 0.39Qp
    8.886.410.610.34No GoodNo GoodNo GoodNo Good
    9
    Qe : 0.39QpQa : 0.61Qp
    6.227.330.240.35No GoodNo GoodAcceptNo Good
    10
    Qe : 0.42QpQa : 0.58Qp
    6.394.790.300.19No GoodAcceptNo GoodAccept

    2.3.4 방류량 배분 비율의 허용 방류량 검토

    계획 홍수량 방류 시 기존 여수로와 보조 여수로의 배분 비율 검토 결과 Case 10(Qe = 0.42Qp, Qa = 0.58Qp)에서 방류에 따른 하류 하천의 피해를 최소화시킬 수 있는 것을 확인하였다. 그러나 대안부 전 구간에 대하여 호안 설계조건을 만족하지 못하였다. 따라서 기존 여수로와 보조 여수로의 방류 배분 비율을 고정시킨 후 총 방류량을 조절하여 허용 방류량을 검토하였다(Case 11 ~ Case 14).

    호안 안정성 측면에서 검토한 결과 계획홍수량 대비 총 방류량이 감소하면 최대 유속 및 최대 소류력이 감소하고 최종적으로 계획 홍수량의 77%를 방류할 경우 하류하천의 대안부에서 호안 설계조건을 모두 만족하는 것을 확인하였다(Fig. 10Fig. 11 참조). 각 Case 별 대안부에서 최대 유속결과 및 산정한 소류력은 Table 7에 제시하였다. 또한 Case 별 수위 검토 결과 처오름으로 인한 대안부 전 구간에서 월류에 대한 안정성(ηmax/ηref<0.97(=기설제방고))은 확보하였다(Fig. 12 참조).

    Table 7.

    Numerical results for each cases (Case 11 ~ Case 14)

    Case (Qe &amp; Qa)Maximum Velocity
    (Vmax, m/s)
    Maximum Shear
    (τmax, kN/m2)
    Evaluation in terms of VpEvaluation in terms of τp
    Section 1Section 2Section 1Section 2Section 1Section 2Section 1Section 2
    11
    Qe : 0.32QpQa : 0.45Qp
    3.634.530.090.26AcceptAcceptAcceptAccept
    12
    Qe : 0.35QpQa : 0.48Qp
    5.745.180.230.22No GoodNo GoodAcceptAccept
    13
    Qe : 0.38QpQa : 0.53Qp
    6.704.210.280.11No GoodAcceptAcceptAccept
    14
    Qe : 0.41QpQa : 0.56Qp
    6.545.240.280.24No GoodNo GoodAcceptAccept
    /media/sites/ksds/2021-014-02/N0240140207/images/ksds_14_02_07_F10.jpg
    Fig. 10

    Maximum velocity on section 1 & 2 according to total outflow

    /media/sites/ksds/2021-014-02/N0240140207/images/ksds_14_02_07_F11.jpg
    Fig. 11

    Maximum shear on section 1 & 2 according to total outflow

    /media/sites/ksds/2021-014-02/N0240140207/images/ksds_14_02_07_F12.jpg
    Fig. 12

    Maximum water surface elevation on section 1 & 2 according to total outflow

    3. 결 론

    본 연구에서는 홍수 시 기존 여수로의 노후화로 인한 보조 여수로의 활용방안에 대하여 하류하천의 호안 안정성 측면에서 검토하였다. 여수로 방류로 인한 하류하천의 흐름특성을 검토하기 위하여 3차원 수치모형인 FLOW-3D를 활용하였고, 여수로 지형은 치수능력 증대사업을 통하여 완공된 ○○댐의 제원을 이용하였다. 하류하천 조도 계수 및 여수로 방류량은 하천기본계획을 참고하여 적용하였다. 최종적으로 여수로 방류로 인한 하류하천의 피해를 최소화 시킬 수 있는 적절한 보조 여수로의 활용방안을 도출하기 위하여 보조 여수로 단독 운영과 기존 여수로와의 동시 운영에 따른 하류 하천의 흐름특성 및 소류력의 변화를 검토하였다.

    수문은 완전 개도 상태에서 방류한다는 가정으로 계획 홍수량 조건에서 보조 여수로 단독 운영 시 하류하천 대안부의 유속 및 수위를 검토한 결과 기존 여수로 단독운영에 비하여 최대 유속 및 최대 수위가 감소하는 것을 확인할 수 있었으며, 이는 보조 여수로 단독 운영 시 하류하천으로 유입각도가 작아지고, 유입되는 하천의 폭이 증가되기 때문이다. 그러나 계획 홍수량 조건에서 하천호안 설계기준에서 제시한 허용 유속(5.0 m/s)과 허용 소류력(0.28 kN/m2)과 비교하였을 때 호안 안정성을 확보하지 못하였으며, 계획홍수량의 45% 이하 방류 시에 대안부의 호안 안정성을 확보하였다. 수위의 경우 여수로 방류에 따른 대안부에서 처오름 현상이 발생하여 월류에 대한 위험성을 확인하였고 이를 통하여 기존 여수로와의 동시 운영 방안을 도출하는 것이 중요하다고 판단된다. 따라서 기존 여수로와의 동시 운영 측면에서 기존 여수로와 보조 여수로의 배분 비율 및 총 방류량을 변화시켜가며 하류 하천의 흐름특성 및 소류력의 변화를 검토하였다. 배분 비율의 경우 기존 여수로와 보조 여수로의 균등 배분(Case 7) 및 편중 배분(Case 8 & Case 9)을 검토하여 보조 여수로의 방류량이 기존 여수로의 방류량보다 큰 경우 하류하천의 중심부로 집중되어 대안부의 최대유속, 최대소류력 및 최대수위가 감소하는 것을 확인하였다. 이를 근거로 기존 여수로의 방류 비율을 증가(Qe=0.42Qp, Qa=0.58Qp)시켜 검토한 결과 대안부 일부 구간에서 허용 유속 및 허용소류력 조건을 만족하는 것을 확인하였다. 이를 통하여 기존 여수로와 보조 여수로의 동시 운영을 통하여 적절한 방류량 배분 비율을 도출하는 것이 방류로 인한 하류하천의 피해를 저감하는데 효과적인 것으로 판단된다. 그러나 설계홍수량 방류 시 전 구간에서 허용 유속 및 소류력 조건을 만족하지 못하였다. 최종적으로 전체 방류량에서 기존 여수로의 방류 비율을 42%, 보조 여수로의 방류 비율을 58%로 설정하여 허용방류량을 검토한 결과, 계획홍수량의 77%이하로 방류 시 대안부의 최대유속은 기존여수로 방류의 지배영향구간(section 1)에서 3.63 m/s, 기존 여수로와 보조 여수로 방류의 영향구간(section 2)에서 4.53 m/s로 허용유속 조건을 만족하였고, 산정한 소류력도 각각 0.09 kN/m2 및 0.26 kN/m2로 허용 소류력 조건을 만족하여 대안부 호안의 안정성을 확보하였다고 판단된다.

    본 연구 결과는 기후변화 및 기존여수로의 노후화로 인하여 홍수 시 기존여수로의 단독운영으로 하류하천의 피해가 발생할 수 있는 현시점에서 치수증대 사업으로 완공된 보조 여수로의 활용방안에 대한 기초자료로 활용될 수 있고, 향후 계획 홍수량 유입 시 최적의 배분 비율 및 허용 방류량 도출에 이용할 수 있다. 다만 본 연구는 여수로 방류에 따른 제방에 작용하는 수충력은 검토하지 못하고, 허용 유속 및 허용소류력은 제방과 유수의 방향이 일정한 구간에 대하여 검토하였다. 또한 여수로 방류에 따른 대안부에서의 영향에 대해서만 검토하였고 수문 전면 개도 조건에서 검토하였다는 한계점은 분명히 있다. 이에 향후에는 다양한 수문 개도 조건 및 방류 시나리오를 적용 및 검토하여 보다 효율적이고, 효과적인 보조 여수로 활용방안을 도출하고자 한다.

    Acknowledgements

    본 결과물은 K-water에서 수행한 기존 및 신규 여수로 효율적 연계운영 방안 마련(2021-WR-GP-76-149)의 지원을 받아 연구되었습니다.

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    Figure 17. Longitudinal turbulent kinetic energy distribution on the smooth and triangular macroroughnesses: (A) Y/2; (B) Y/6.

    Numerical Simulations of the Flow Field of a Submerged Hydraulic Jump over Triangular Macroroughnesses

    Triangular Macroroughnesses 대한 잠긴 수압 점프의 유동장 수치 시뮬레이션

    by Amir Ghaderi 1,2,Mehdi Dasineh 3,Francesco Aristodemo 2 andCostanza Aricò 4,*1Department of Civil Engineering, Faculty of Engineering, University of Zanjan, Zanjan 537138791, Iran2Department of Civil Engineering, University of Calabria, Arcavacata, 87036 Rende, Italy3Department of Civil Engineering, Faculty of Engineering, University of Maragheh, Maragheh 8311155181, Iran4Department of Engineering, University of Palermo, Viale delle Scienze, 90128 Palermo, Italy*Author to whom correspondence should be addressed.Academic Editor: Anis YounesWater202113(5), 674; https://doi.org/10.3390/w13050674

    Abstract

    The submerged hydraulic jump is a sudden change from the supercritical to subcritical flow, specified by strong turbulence, air entrainment and energy loss. Despite recent studies, hydraulic jump characteristics in smooth and rough beds, the turbulence, the mean velocity and the flow patterns in the cavity region of a submerged hydraulic jump in the rough beds, especially in the case of triangular macroroughnesses, are not completely understood. The objective of this paper was to numerically investigate via the FLOW-3D model the effects of triangular macroroughnesses on the characteristics of submerged jump, including the longitudinal profile of streamlines, flow patterns in the cavity region, horizontal velocity profiles, streamwise velocity distribution, thickness of the inner layer, bed shear stress coefficient, Turbulent Kinetic Energy (TKE) and energy loss, in different macroroughness arrangements and various inlet Froude numbers (1.7 < Fr1 < 9.3). To verify the accuracy and reliability of the present numerical simulations, literature experimental data were considered.

    Keywords: submerged hydraulic jumptriangular macroroughnessesTKEbed shear stress coefficientvelocityFLOW-3D model

    수중 유압 점프는 강한 난류, 공기 동반 및 에너지 손실로 지정된 초임계에서 아임계 흐름으로의 급격한 변화입니다. 최근 연구에도 불구하고, 특히 삼각형 거시적 거칠기의 경우, 평활 및 거친 베드에서의 수압 점프 특성, 거친 베드에서 잠긴 수압 점프의 공동 영역에서 난류, 평균 속도 및 유동 패턴이 완전히 이해되지 않았습니다.

    이 논문의 목적은 유선의 종방향 프로파일, 캐비티 영역의 유동 패턴, 수평 속도 프로파일, 스트림 방향 속도 분포, 두께를 포함하여 서브머지드 점프의 특성에 대한 삼각형 거시 거칠기의 영향을 FLOW-3D 모델을 통해 수치적으로 조사하는 것이었습니다.

    내부 층의 층 전단 응력 계수, 난류 운동 에너지(TKE) 및 에너지 손실, 다양한 거시 거칠기 배열 및 다양한 입구 Froude 수(1.7 < Fr1 < 9.3). 현재 수치 시뮬레이션의 정확성과 신뢰성을 검증하기 위해 문헌 실험 데이터를 고려했습니다.

     Introduction

    격렬한 난류 혼합과 기포 동반이 있는 수압 점프는 초임계에서 아임계 흐름으로의 변화 과정으로 간주됩니다[1]. 자유 및 수중 유압 점프는 일반적으로 게이트, 배수로 및 둑과 같은 수력 구조 아래의 에너지 손실에 적합합니다. 매끄러운 베드에서 유압 점프의 특성은 널리 연구되었습니다[2,3,4,5,6,7,8,9].

    베드의 거칠기 요소가 매끄러운 베드와 비교하여 수압 점프의 특성에 어떻게 영향을 미치는지 예측하기 위해 거시적 거칠기에 대한 자유 및 수중 수력 점프에 대해 여러 실험 및 수치 연구가 수행되었습니다. Ead와 Rajaratnam[10]은 사인파 거대 거칠기에 대한 수리학적 점프의 특성을 조사하고 무차원 분석을 통해 수면 프로파일과 배출을 정규화했습니다.

    Tokyayet al. [11]은 두 사인 곡선 거대 거칠기에 대한 점프 길이 비율과 에너지 손실이 매끄러운 베드보다 각각 35% 더 작고 6% 더 높다는 것을 관찰했습니다. Abbaspur et al. [12]는 6개의 사인파형 거대 거칠기에 대한 수력학적 점프의 특성을 연구했습니다. 그 결과, 꼬리수심과 점프길이는 평상보다 낮았고 Froude 수는 점프길이에 큰 영향을 미쳤습니다.

    Shafai-Bejestan과 Neisi[13]는 수압 점프에 대한 마름모꼴 거대 거칠기의 영향을 조사했습니다. 결과는 마름모꼴 거시 거칠기를 사용하면 매끄러운 침대와 비교하여 꼬리 수심과 점프 길이를 감소시키는 것으로 나타났습니다. Izadjoo와 Shafai-Bejestan[14]은 다양한 사다리꼴 거시 거칠기에 대한 수압 점프를 연구했습니다.

    그들은 전단응력계수가 평활층보다 10배 이상 크고 점프길이가 50% 감소하는 것을 관찰하였습니다. Nikmehr과 Aminpour[15]는 Flow-3D 모델 버전 11.2[16]를 사용하여 사다리꼴 블록이 있는 거시적 거칠기에 대한 수력학적 점프의 특성을 조사했습니다. 결과는 거시 거칠기의 높이와 거리가 증가할수록 전단 응력 계수뿐만 아니라 베드 근처에서 속도가 감소하는 것으로 나타났습니다.

    Ghaderi et al. [17]은 다양한 형태의 거시 거칠기(삼각형, 정사각형 및 반 타원형)에 대한 자유 및 수중 수력 점프 특성을 연구했습니다. 결과는 Froude 수의 증가에 따라 자유 및 수중 점프에서 전단 응력 계수, 에너지 손실, 수중 깊이, 미수 깊이 및 상대 점프 길이가 증가함을 나타냅니다.

    자유 및 수중 점프에서 가장 높은 전단 응력과 에너지 손실은 삼각형의 거시 거칠기가 존재할 때 발생했습니다. Elsebaie와 Shabayek[18]은 5가지 형태의 거시적 거칠기(삼각형, 사다리꼴, 2개의 측면 경사 및 직사각형이 있는 정현파)에 대한 수력학적 점프의 특성을 연구했습니다. 결과는 모든 거시적 거칠기에 대한 에너지 손실이 매끄러운 베드에서보다 15배 이상이라는 것을 보여주었습니다.

    Samadi-Boroujeni et al. [19]는 다양한 각도의 6개의 삼각형 거시 거칠기에 대한 수력 점프를 조사한 결과 삼각형 거시 거칠기가 평활 베드에 비해 점프 길이를 줄이고 에너지 손실과 베드 전단 응력 계수를 증가시키는 것으로 나타났습니다.

    Ahmed et al. [20]은 매끄러운 베드와 삼각형 거시 거칠기에서 수중 수력 점프 특성을 조사했습니다. 결과는 부드러운 침대와 비교할 때 잠긴 깊이와 점프 길이가 감소했다고 밝혔습니다. 표 1은 다른 연구자들이 제시한 과거의 유압 점프에 대한 실험 및 수치 연구의 세부 사항을 나열합니다.

    Table 1. Main characteristics of some past experimental and numerical studies on hydraulic jumps.

    ReferenceShape Bed-Channel Type-
    Jump Type
    Channel Dimension (m)Roughness (mm)Fr1Investigated Flow
    Properties
    Ead and Rajaratnam [10]-Smooth and rough beds-Rectangular channel-Free jumpCL1 = 7.60
    CW2 = 0.44
    CH3 = 0.60
    -Corrugated sheets (RH4 = 13 and 22)4–10-Upstream and tailwater depths-Jump length-Roller length-Velocity-Water surface profile
    Tokyay et al. [11]-Smooth and rough beds-Rectangular channel-Free jumpCL = 10.50
    CW = 0.253
    CH = 0.432
    -Two sinusoidal corrugated (RH = 10 and 13)5–12-Depth ratio-Jump length-Energy loss
    Izadjoo and Shafai-Bejestan [14]-Smooth and rough beds-Two rectangular-channel-Free jumpCL = 1.2, 9
    CW = 0.25, 0.50
    CH = 0.40
    Baffle with trapezoidal cross section
    (RH: 13 and 26)
    6–12-Upstream and tailwater depths-Jump length-Velocity-Bed shear stress coefficient
    Abbaspour et al. [12]-Horizontal bed with slope 0.002-Rectangular channel—smooth and rough beds-Free jumpCL = 10
    CW = 0.25
    CH = 0.50
    -Sinusoidal bed (RH = 15,20, 25 and 35)3.80–8.60-Water surface profile-Depth ratio-Jump length-Energy loss-Velocity profiles-Bed shear stress coefficient
    Shafai-Bejestan and Neisi [13]-Smooth and rough beds-Rectangular channel-Free jumpCL = 7.50
    CW = 0.35
    CH = 0.50
    Lozenge bed4.50–12-Sequent depth-Jump length
    Elsebaie and Shabayek [18]-Smooth and rough beds-Rectangular channel-With side slopes of 45 degrees for two trapezoidal and triangular macroroughnesses and of 60 degrees for other trapezoidal macroroughnesses-Free jumpCL = 9
    CW = 0.295
    CH = 0.32
    -Sinusoidal-Triangular-Trapezoidal with two side-Rectangular-(RH = 18 and corrugation wavelength = 65)50-Water surface profile-Sequent depth-Jump length-Bed shear stress coefficient
    Samadi-Boroujeni et al. [19]-Rectangular channel-Smooth and rough beds-Free jumpCL = 12
    CW = 0.40
    CH = 0.40
    -Six triangular corrugated (RH = 2.5)6.10–13.10-Water surface profile-Sequent depth-Jump length-Energy loss-Velocity profiles-Bed shear stress coefficient
    Ahmed et al. [20]-Smooth and rough beds-Rectangular channel-Submerged jumpCL = 24.50
    CW = 0.75
    CH = 0.70
    -Triangular corrugated sheet (RH = 40)1.68–9.29-Conjugated and tailwater depths-Submerged ratio-Deficit depth-Relative jump length-Jump length-Relative roller jump length-Jump efficiency-Bed shear stress coefficient
    Nikmehr and Aminpour [15]-Horizontal bed with slope 0.002-Rectangular channel-Rough bed-Free jumpCL = 12
    CW = 0.25
    CH = 0.50
    -Trapezoidal blocks (RH = 2, 3 and 4)5.01–13.70-Water surface profile-Sequent depth-Jump length-Roller length-Velocity
    Ghaderi et al. [17]-Smooth and rough beds-Rectangular channel-Free and submerged jumpCL = 4.50
    CW = 0.75
    CH = 0.70
    -Triangular, square and semi-oval macroroughnesses (RH = 40 and distance of roughness of I = 40, 80, 120, 160 and 200)1.70–9.30-Horizontal velocity distributions-Bed shear stress coefficient-Sequent depth ratio and submerged depth ratio-Jump length-Energy loss
    Present studyRectangular channel
    Smooth and rough beds
    Submerged jump
    CL = 4.50
    CW = 0.75
    CH = 0.70
    -Triangular macroroughnesses (RH = 40 and distance of roughness of I = 40, 80, 120, 160 and 200)1.70–9.30-Longitudinal profile of streamlines-Flow patterns in the cavity region-Horizontal velocity profiles-Streamwise velocity distribution-Bed shear stress coefficient-TKE-Thickness of the inner layer-Energy loss

    CL1: channel length, CW2: channel width, CH3: channel height, RH4: roughness height.

    이전에 논의된 조사의 주요 부분은 실험실 접근 방식을 기반으로 하며 사인파, 마름모꼴, 사다리꼴, 정사각형, 직사각형 및 삼각형 매크로 거칠기가 공액 깊이, 잠긴 깊이, 점프 길이, 에너지 손실과 같은 일부 자유 및 수중 유압 점프 특성에 어떻게 영향을 미치는지 조사합니다.

    베드 및 전단 응력 계수. 더욱이, 저자[17]에 의해 다양한 형태의 거시적 거칠기에 대한 수력학적 점프에 대한 이전 발표된 논문을 참조하면, 삼각형의 거대조도는 가장 높은 층 전단 응력 계수 및 에너지 손실을 가지며 또한 가장 낮은 잠긴 깊이, tailwater를 갖는 것으로 관찰되었습니다.

    다른 거친 모양, 즉 정사각형 및 반 타원형과 부드러운 침대에 비해 깊이와 점프 길이. 따라서 본 논문에서는 삼각형 매크로 거칠기를 사용하여(일정한 거칠기 높이가 T = 4cm이고 삼각형 거칠기의 거리가 I = 4, 8, 12, 16 및 20cm인 다른 T/I 비율에 대해), 특정 캐비티 영역의 유동 패턴, 난류 운동 에너지(TKE) 및 흐름 방향 속도 분포와 같은 연구가 필요합니다.

    CFD(Computational Fluid Dynamics) 방법은 자유 및 수중 유압 점프[21]와 같은 복잡한 흐름의 모델링 프로세스를 수행하는 중요한 도구로 등장하며 수중 유압 점프의 특성은 CFD 시뮬레이션을 사용하여 정확하게 예측할 수 있습니다 [22,23 ].

    본 논문은 초기에 수중 유압 점프의 주요 특성, 수치 모델에 대한 입력 매개변수 및 Ahmed et al.의 참조 실험 조사를 제시합니다. [20], 검증 목적으로 보고되었습니다. 또한, 본 연구에서는 유선의 종방향 프로파일, 캐비티 영역의 유동 패턴, 수평 속도 프로파일, 내부 층의 두께, 베드 전단 응력 계수, TKE 및 에너지 손실과 같은 특성을 조사할 것입니다.

    Figure 1. Definition sketch of a submerged hydraulic jump at triangular macroroughnesses.
    Figure 1. Definition sketch of a submerged hydraulic jump at triangular macroroughnesses.

    Table 2. Effective parameters in the numerical model.

    Bed TypeQ
    (l/s)
    I
    (cm)
    T (cm)d (cm)y1
    (cm)
    y4
    (cm)
    Fr1= u1/(gy1)0.5SRe1= (u1y1)/υ
    Smooth30, 4551.62–3.839.64–32.101.7–9.30.26–0.5039,884–59,825
    Triangular macroroughnesses30, 454, 8, 12, 16, 20451.62–3.846.82–30.081.7–9.30.21–0.4439,884–59,825
    Figure 2. Longitudinal profile of the experimental flume (Ahmed et al. [20]).
    Figure 2. Longitudinal profile of the experimental flume (Ahmed et al. [20]).

    Table 3. Main flow variables for the numerical and physical models (Ahmed et al. [20]).

    ModelsBed TypeQ (l/s)d (cm)y1 (cm)u1 (m/s)Fr1
    Numerical and PhysicalSmooth4551.62–3.831.04–3.701.7–9.3
    T/I = 0.54551.61–3.831.05–3.711.7–9.3
    T/I = 0.254551.60–3.841.04–3.711.7–9.3
    Figure 3. The boundary conditions governing the simulations.
    Figure 3. The boundary conditions governing the simulations.
    Figure 4. Sketch of mesh setup.
    Figure 4. Sketch of mesh setup.

    Table 4. Characteristics of the computational grids.

    MeshNested Block Cell Size (cm)Containing Block Cell Size (cm)
    10.551.10
    20.651.30
    30.851.70

    Table 5. The numerical results of mesh convergence analysis.

    ParametersAmounts
    fs1 (-)7.15
    fs2 (-)6.88
    fs3 (-)6.19
    K (-)5.61
    E32 (%)10.02
    E21 (%)3.77
    GCI21 (%)3.03
    GCI32 (%)3.57
    GCI32/rp GCI210.98
    Figure 5. Time changes of the flow discharge in the inlet and outlet boundaries conditions (A): Q = 0.03 m3/s (B): Q = 0.045 m3/s.
    Figure 5. Time changes of the flow discharge in the inlet and outlet boundaries conditions (A): Q = 0.03 m3/s (B): Q = 0.045 m3/s.
    Figure 6. The evolutionary process of a submerged hydraulic jump on the smooth bed—Q = 0.03 m3/s.
    Figure 6. The evolutionary process of a submerged hydraulic jump on the smooth bed—Q = 0.03 m3/s.
    Figure 7. Numerical versus experimental basic parameters of the submerged hydraulic jump. (A): y3/y1; and (B): y4/y1.
    Figure 7. Numerical versus experimental basic parameters of the submerged hydraulic jump. (A): y3/y1; and (B): y4/y1.
    Figure 8. Velocity vector field and flow pattern through the gate in a submerged hydraulic jump condition: (A) smooth bed; (B) triangular macroroughnesses.
    Figure 8. Velocity vector field and flow pattern through the gate in a submerged hydraulic jump condition: (A) smooth bed; (B) triangular macroroughnesses.
    Figure 9. Velocity vector distributions in the x–z plane (y = 0) within the cavity region.
    Figure 9. Velocity vector distributions in the x–z plane (y = 0) within the cavity region.
    Figure 10. Typical vertical distribution of the mean horizontal velocity in a submerged hydraulic jump [46].
    Figure 10. Typical vertical distribution of the mean horizontal velocity in a submerged hydraulic jump [46].
    Figure 11. Typical horizontal velocity profiles in a submerged hydraulic jump on smooth bed and triangular macroroughnesses.
    Figure 11. Typical horizontal velocity profiles in a submerged hydraulic jump on smooth bed and triangular macroroughnesses.
    Figure 12. Horizontal velocity distribution at different distances from the sluice gate for the different T/I for Fr1 = 6.1
    Figure 12. Horizontal velocity distribution at different distances from the sluice gate for the different T/I for Fr1 = 6.1
    Figure 13. Stream-wise velocity distribution for the triangular macroroughnesses with T/I = 0.5 and 0.25.
    Figure 13. Stream-wise velocity distribution for the triangular macroroughnesses with T/I = 0.5 and 0.25.
    Figure 14. Dimensionless horizontal velocity distribution in the submerged hydraulic jump for different Froude numbers in triangular macroroughnesses.
    Figure 14. Dimensionless horizontal velocity distribution in the submerged hydraulic jump for different Froude numbers in triangular macroroughnesses.
    Figure 15. Spatial variations of (umax/u1) and (δ⁄y1).
    Figure 15. Spatial variations of (umax/u1) and (δ⁄y1).
    Figure 16. The shear stress coefficient (ε) versus the inlet Froude number (Fr1).
    Figure 16. The shear stress coefficient (ε) versus the inlet Froude number (Fr1).
    Figure 17. Longitudinal turbulent kinetic energy distribution on the smooth and triangular macroroughnesses: (A) Y/2; (B) Y/6.
    Figure 17. Longitudinal turbulent kinetic energy distribution on the smooth and triangular macroroughnesses: (A) Y/2; (B) Y/6.
    Figure 18. The energy loss (EL/E3) of the submerged jump versus inlet Froude number (Fr1).
    Figure 18. The energy loss (EL/E3) of the submerged jump versus inlet Froude number (Fr1).

    Conclusions

    • 본 논문에서는 유선의 종방향 프로파일, 공동 영역의 유동 패턴, 수평 속도 프로파일, 스트림 방향 속도 분포, 내부 층의 두께, 베드 전단 응력 계수, 난류 운동 에너지(TKE)를 포함하는 수중 유압 점프의 특성을 제시하고 논의했습니다. ) 및 삼각형 거시적 거칠기에 대한 에너지 손실. 이러한 특성은 FLOW-3D® 모델을 사용하여 수치적으로 조사되었습니다. 자유 표면을 시뮬레이션하기 위한 VOF(Volume of Fluid) 방법과 난류 RNG k-ε 모델이 구현됩니다. 본 모델을 검증하기 위해 평활층과 삼각형 거시 거칠기에 대해 수치 시뮬레이션과 실험 결과를 비교했습니다. 본 연구의 다음과 같은 결과를 도출할 수 있다.
    • 개발 및 개발 지역의 삼각형 거시 거칠기의 흐름 패턴은 수중 유압 점프 조건의 매끄러운 바닥과 비교하여 더 작은 영역에서 동일합니다. 삼각형의 거대 거칠기는 거대 거칠기 사이의 공동 영역에서 또 다른 시계 방향 와류의 형성으로 이어집니다.
    • T/I = 1, 0.5 및 0.33과 같은 거리에 대해 속도 벡터 분포는 캐비티 영역에서 시계 방향 소용돌이를 표시하며, 여기서 속도의 크기는 평균 유속보다 훨씬 작습니다. 삼각형 거대 거칠기(T/I = 0.25 및 0.2) 사이의 거리를 늘리면 캐비티 영역에 크기가 다른 두 개의 소용돌이가 형성됩니다.
    • 삼각형 거시조도 사이의 거리가 충분히 길면 흐름이 다음 조도에 도달할 때까지 속도 분포가 회복됩니다. 그러나 짧은 거리에서 흐름은 속도 분포의 적절한 회복 없이 다음 거칠기에 도달합니다. 따라서 거시 거칠기 사이의 거리가 감소함에 따라 마찰 계수의 증가율이 감소합니다.
    • 삼각형의 거시적 거칠기에서, 잠수 점프의 지정된 섹션에서 최대 속도는 자유 점프보다 높은 값으로 이어집니다. 또한, 수중 점프에서 두 가지 유형의 베드(부드러움 및 거친 베드)에 대해 깊이 및 와류 증가로 인해 베드로부터의 최대 속도 거리는 감소합니다. 잠수 점프에서 경계층 두께는 자유 점프보다 얇습니다.
    • 매끄러운 베드의 난류 영역은 게이트로부터의 거리에 따라 생성되고 자유 표면 롤러 영역 근처에서 발생하는 반면, 거시적 거칠기에서는 난류가 게이트 근처에서 시작되어 더 큰 강도와 제한된 스위프 영역으로 시작됩니다. 이는 반시계 방향 순환의 결과입니다. 거시 거칠기 사이의 공간에서 자유 표면 롤러 및 시계 방향 와류.
    • 삼각 거시 거칠기에서 침지 점프의 베드 전단 응력 계수와 에너지 손실은 유입구 Froude 수의 증가에 따라 증가하는 매끄러운 베드에서 발견된 것보다 더 큽니다. T/I = 0.50 및 0.20에서 최고 및 최저 베드 전단 응력 계수 및 에너지 손실이 평활 베드에 비해 거칠기 요소의 거리가 증가함에 따라 발생합니다.
    • 거의 거칠기 요소가 있는 삼각형 매크로 거칠기의 존재에 의해 주어지는 점프 길이와 잠긴 수심 및 꼬리 수심의 감소는 결과적으로 크기, 즉 길이 및 높이가 감소하는 정수조 설계에 사용될 수 있습니다.
    • 일반적으로 CFD 모델은 다양한 수력 조건 및 기하학적 배열을 고려하여 잠수 점프의 특성 예측을 시뮬레이션할 수 있습니다. 캐비티 영역의 흐름 패턴, 흐름 방향 및 수평 속도 분포, 베드 전단 응력 계수, TKE 및 유압 점프의 에너지 손실은 수치적 방법으로 시뮬레이션할 수 있습니다. 그러나 거시적 차원과 유동장 및 공동 유동의 변화에 ​​대한 다양한 배열에 대한 연구는 향후 과제로 남아 있다.

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    Fig. 1. Schematic of (a) geometry of the simulation model, (b) A-A cross-section presenting the locations of point probes for recording temperature history (unit: µm).

    Laser powder bed fusion of 17-4 PH stainless steel: a comparative study on the effect of heat treatment on the microstructure evolution and mechanical properties

    17-4 PH 스테인리스강의 레이저 분말 베드 융합: 열처리가 미세조직의 진화 및 기계적 특성에 미치는 영향에 대한 비교 연구

    panelS.Saboonia, A.Chaboka, S.Fenga,e, H.Blaauwb, T.C.Pijperb,c, H.J.Yangd, Y.T.Peia
    aDepartment of Advanced Production Engineering, Engineering and Technology Institute Groningen, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, The Netherlands
    bPhilips Personal Care, Oliemolenstraat 5, 9203 ZN, Drachten, The Netherlands
    cInnovation Cluster Drachten, Nipkowlaan 5, 9207 JA, Drachten, The Netherlands
    dShi-changxu Innovation Center for Advanced Materials, Institute of Metal Research, Chinese Academy of Sciences, 72 Wenhua Road, Shenyang 110016, P. R. China
    eSchool of Mechanical Engineering, University of Science and Technology Beijing, Beijing, 100083, P.R. China

    Abstract

    17-4 PH (precipitation hardening) stainless steel is commonly used for the fabrication of complicated molds with conformal cooling channels using laser powder bed fusion process (L-PBF). However, their microstructure in the as-printed condition varies notably with the chemical composition of the feedstock powder, resulting in different age-hardening behavior. In the present investigation, 17-4 PH stainless steel components were fabricated by L-PBF from two different feedstock powders, and subsequently subjected to different combinations of post-process heat treatments. It was observed that the microstructure in as-printed conditions could be almost fully martensitic or ferritic, depending on the ratio of Creq/Nieq of the feedstock powder. Aging treatment at 480 °C improved the yield and ultimate tensile strengths of the as-printed components. However, specimens with martensitic structures exhibited accelerated age-hardening response compared with the ferritic specimens due to the higher lattice distortion and dislocation accumulation, resulting in the “dislocation pipe diffusion mechanism”. It was also found that the martensitic structures were highly susceptible to the formation of reverted austenite during direct aging treatment, where 19.5% of austenite phase appeared in the microstructure after 15 h of direct aging. Higher fractions of reverted austenite activates the transformation induced plasticity and improves the ductility of heat treated specimens. The results of the present study can be used to tailor the microstructure of the L-PBF printed 17-4 PH stainless steel by post-process heat treatments to achieve a good combination of mechanical properties.

    17-4 PH(석출 경화) 스테인리스강은 레이저 분말 베드 융합 공정(L-PBF)을 사용하여 등각 냉각 채널이 있는 복잡한 금형 제작에 일반적으로 사용됩니다. 그러나 인쇄된 상태의 미세 구조는 공급원료 분말의 화학적 조성에 따라 크게 달라지므로 시효 경화 거동이 다릅니다.

    현재 조사에서 17-4 PH 스테인리스강 구성요소는 L-PBF에 의해 두 가지 다른 공급원료 분말로 제조되었으며, 이후에 다양한 조합의 후처리 열처리를 거쳤습니다. 인쇄된 상태의 미세구조는 공급원료 분말의 Creq/Nieq 비율에 따라 거의 완전히 마르텐사이트 또는 페라이트인 것으로 관찰되었습니다.

    480 °C에서 노화 처리는 인쇄된 구성 요소의 수율과 극한 인장 강도를 개선했습니다. 그러나 마텐자이트 구조의 시편은 격자 변형 및 전위 축적이 높아 페라이트 시편에 비해 시효 경화 반응이 가속화되어 “전위 파이프 확산 메커니즘”이 발생합니다.

    또한 마르텐사이트 구조는 직접 시효 처리 중에 복귀된 오스테나이트의 형성에 매우 민감한 것으로 밝혀졌으며, 여기서 15시간의 직접 시효 후 미세 조직에 19.5%의 오스테나이트 상이 나타났습니다.

    복귀된 오스테나이트의 비율이 높을수록 변형 유도 가소성이 활성화되고 열처리된 시편의 연성이 향상됩니다. 본 연구의 결과는 기계적 특성의 우수한 조합을 달성하기 위해 후처리 열처리를 통해 L-PBF로 인쇄된 17-4 PH 스테인리스강의 미세 구조를 조정하는 데 사용할 수 있습니다.

    Keywords

    Laser powder bed fusion17-4 PH stainless steelPost-process heat treatmentAge hardeningReverted austenite

    Fig. 1. Schematic of (a) geometry of the simulation model, (b) A-A cross-section presenting the locations of point probes for recording temperature history (unit: µm).
    Fig. 1. Schematic of (a) geometry of the simulation model, (b) A-A cross-section presenting the locations of point probes for recording temperature history (unit: µm).
    Fig. 2. Optical (a, b) and TEM (c) micrographs of the wrought 17-4 PH stainless steel.
    Fig. 2. Optical (a, b) and TEM (c) micrographs of the wrought 17-4 PH stainless steel.
    Fig. 3. EBSD micrographs of the as-printed 17-4 PH steel fabricated with “powder A” (a, b) and “powder B” (c, d) on two different cross sections: (a, c) perpendicular to the building direction, and (b, d) parallel to the building direction.
    Fig. 3. EBSD micrographs of the as-printed 17-4 PH steel fabricated with “powder A” (a, b) and “powder B” (c, d) on two different cross sections: (a, c) perpendicular to the building direction, and (b, d) parallel to the building direction.
    Fig. 4. Microstructure of the as-printed 17-4 PH stainless steel fabricated with “powder A” (a) and “powder B” (b).
    Fig. 4. Microstructure of the as-printed 17-4 PH stainless steel fabricated with “powder A” (a) and “powder B” (b).
    Fig. 5. Simulated temperature history of the probes located at the cross section of the L-PBF 17-4 PH steel sample.
    Fig. 5. Simulated temperature history of the probes located at the cross section of the L-PBF 17-4 PH steel sample.
    Fig. 6. Dependency of the volume fraction of delta ferrite in the final microstructure of L-PBF printed 17-4 PH steel as a function of Creq/Nieq.
    Fig. 6. Dependency of the volume fraction of delta ferrite in the final microstructure of L-PBF printed 17-4 PH steel as a function of Creq/Nieq.
    Fig. 7. IQ + IPF (left column), parent austenite grain maps (middle column) and phase maps (right column, green color = martensite, red color = austenite) of the post-process heat treated 17-4 PH stainless steel: (a-c) direct aged, (d-f) HIP + aging, (g-i) SA + Aging, and (j-l) HIP + SA + aging (all sample were printed with “powder A”).
    Fig. 7. IQ + IPF (left column), parent austenite grain maps (middle column) and phase maps (right column, green color = martensite, red color = austenite) of the post-process heat treated 17-4 PH stainless steel: (a-c) direct aged, (d-f) HIP + aging, (g-i) SA + Aging, and (j-l) HIP + SA + aging (all sample were printed with “powder A”).
    Fig. 8. TEM micrographs of the post process heat treated 17-4 PH stainless steel: (a) direct aging and (b) HIP + aging (printed with “powder A”).
    Fig. 8. TEM micrographs of the post process heat treated 17-4 PH stainless steel: (a) direct aging and (b) HIP + aging (printed with “powder A”).
    Fig. 9. XRD patterns of the post-process heat treated 17-4 PH stainless steel printed with “powder A”.
    Fig. 9. XRD patterns of the post-process heat treated 17-4 PH stainless steel printed with “powder A”.
    Fig. 10. (a) Volume fraction of reverted austenite as a function of aging time for “direct aging” condition, (b) phase map (green color = martensite, red color = austenite) of the 15 h direct aged specimen printed with “powder A”.
    Fig. 10. (a) Volume fraction of reverted austenite as a function of aging time for “direct aging” condition, (b) phase map (green color = martensite, red color = austenite) of the 15 h direct aged specimen printed with “powder A”.
    Fig. 11. Microhardness variations of the “direct aged” specimens as a function of aging time at 480 °C.
    Fig. 11. Microhardness variations of the “direct aged” specimens as a function of aging time at 480 °C.
    Fig. 12. Kernel average misorientation graphs of the as-printed 17-4 PH steel with (a) martensitic structure (printed with “powder A”) and (b) ferritic structure (printed with “powder b”).
    Fig. 12. Kernel average misorientation graphs of the as-printed 17-4 PH steel with (a) martensitic structure (printed with “powder A”) and (b) ferritic structure (printed with “powder b”).
    Fig. 13. Typical stress-strain curves (a) along with the yield and ultimate tensile strengths (b) and elongation (c) of the as-printed and post-process heat treated 17-4 PH stainless steel (all sample are fabricated with “powder A”).
    Fig. 13. Typical stress-strain curves (a) along with the yield and ultimate tensile strengths (b) and elongation (c) of the as-printed and post-process heat treated 17-4 PH stainless steel (all sample are fabricated with “powder A”).
    Fig. 14. (a) IQ + IPF and (b) phase map (green color = martensite, red color = austenite) of the “direct aged” specimen after tensile test at a location nearby the rupture point (tension direction from left to right).
    Fig. 14. (a) IQ + IPF and (b) phase map (green color = martensite, red color = austenite) of the “direct aged” specimen after tensile test at a location nearby the rupture point (tension direction from left to right).

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    Flow on the inclined drop with bat-shaped elements: (a) Non-submerged flow

    Numerical Methods in Civil Engineering

    Rasoul Daneshfaraz*, Ehsan Aminvash**, Silvia Di Francesco***, Amir Najibi**, John Abraham****

    토목공학의 수치해석법

    Abstract

    The main purpose of this study is to provide a method to increase energy dissipation on an inclined drop. Therefore, three types of rough elements with cylindrical, triangular and batshaped geometries are used on the inclined slope in the relative critical depth range of 0.128 to 0.36 and the effect of the geometry of these elements is examined using Flow 3D software. The results showed demonstrate that the downstream relative depth obtained from the numerical analysis is in good agreement with the laboratory results. The application of rough elements on the inclined drop increased the downstream relative depth and also the relative energy dissipation. The application of rough elements on the sloping surface of the drop significantly reduced the downstream Froude number, so that the Froude number in all models ranging from 4.7~7.5 to 1.45~3.36 also decreased compared to the plain drop. Bat-shaped elements are structurally smaller in size, so the use of these elements, in addition to dissipating more energy, is also economically viable.

    이 연구의 주요 목적은 경사진 낙하에서 에너지 소산을 증가시키는 방법을 제공하는 것입니다. 따라서 0.128 ~ 0.36의 상대 임계 깊이 범위에서 경사면에 원통형, 삼각형 및 박쥐 모양의 형상을 가진 세 가지 유형의 거친 요소가 사용되며 이러한 요소의 형상의 영향은 Flow 3D 소프트웨어를 사용하여 조사됩니다. 결과는 수치 분석에서 얻은 하류 상대 깊이가 실험실 결과와 잘 일치함을 보여줍니다. 경 사진 낙하에 거친 요소를 적용하면 하류 상대 깊이와 상대 에너지 소산이 증가했습니다. 낙차 경사면에 거친 요소를 적용하면 하류의 Froude 수를 크게 감소시켜 4.7~7.5에서 1.45~3.36 범위의 모든 모델에서 Froude 수도 일반 낙차에 비해 감소했습니다. 박쥐 모양의 요소는 구조적으로 크기가 더 작기 때문에 더 많은 에너지를 분산시키는 것 외에도 이러한 요소를 사용하는 것이 경제적으로도 가능합니다.

    Keywords: Downstream depth, Energy dissipation, Froude number, Inclined drop, Roughness elements

    Introduction

    급수 네트워크 시스템, 침식 수로, 수처리 시스템 및 경사가 큰 경우 흐름 에너지를 더 잘 제어하기 위해 경사 방울을 사용할 수 있습니다. 낙하 구조는 지반의 자연 경사를 설계 경사로 변환하여 에너지 소산, 유속 감소 및 수심 증가를 유발합니다. 따라서 흐름의 하류 에너지를 분산 시키기 위해 에너지 분산 구조를 사용할 수 있습니다. 난기류와 혼합된 물과 공기의 형성은 에너지 소비를 증가 시키는 효과적인 방법입니다. 흐름 경로에서 거칠기 요소를 사용하는 것은 에너지 소산을 위한 알려진 방법입니다. 이러한 요소는 흐름 경로에 배치됩니다. 그들은 종종 에너지 소산을 증가시키기 위해 다른 기하학적 구조와 배열을 가지고 있습니다. 이 연구의 목적은 직사각형 경사 방울에 대한 거칠기 요소의 영향을 조사하는 것입니다.

    Fig. 1: Model made in Ardabil, Iran
    Fig. 1: Model made in Ardabil, Iran
    Fig. 2: Geometric and hydraulic parameters of an inclined drop equipped with roughness elements
    Fig. 2: Geometric and hydraulic parameters of an inclined drop equipped with roughness elements
    Fig. 3: Views of the incline with (a) Bat-shaped, (b) Cylindrical, (c) Triangular roughness elements
    Fig. 3: Views of the incline with (a) Bat-shaped, (b) Cylindrical, (c) Triangular roughness elements
    Fig. 4: Geometric profile of inclined drop and boundary conditions with the bat-shape roughness element
    Fig. 4: Geometric profile of inclined drop and boundary conditions with the bat-shape roughness element
    Fig. 5: Variation of the RMSE varying cell size
    Fig. 5: Variation of the RMSE varying cell size
    Fig. 6: Numerical and laboratory comparison of the downstream relative depth
    Fig. 6: Numerical and laboratory comparison of the downstream relative depth
    Fig. 7: Flow profile on inclined drop in discharge of 5 L/s: (a) Without roughness elements; (b) Bat-shaped roughness element; (c) Cylindrical roughness element; (d) Triangular roughness element
    Fig. 7: Flow profile on inclined drop in discharge of 5 L/s: (a) Without roughness elements; (b) Bat-shaped roughness element; (c) Cylindrical roughness element; (d) Triangular roughness element
    Fig. 8: Relative edge depth versus the relative critical depth
    Fig. 8: Relative edge depth versus the relative critical depth
    Flow on the inclined drop with bat-shaped elements: (a) Non-submerged flow
    Flow on the inclined drop with bat-shaped elements: (a) Non-submerged flow
    Fig. 9: Flow on the inclined drop with bat-shaped elements: (b) Submerged flow
    Fig. 9: Flow on the inclined drop with bat-shaped elements: (b) Submerged flow
    Fig. 10: Relative downstream depth versus the relative critical depth
    Fig. 10: Relative downstream depth versus the relative critical depth
    Fig. 11: Relative downstream depth versus the relative critical depth
    Fig. 11: Relative downstream depth versus the relative critical depth

    Conclusions

    현재 연구에서 FLOW-3D 소프트웨어를 사용하여 한 높이, 한 각도, 밀도 15% 및 지그재그 배열에서 삼각형, 원통형 및 박쥐 모양의 형상을 가진 세 가지 유형의 거칠기 요소를 사용하여 경사 낙하 수리학적 매개변수에 대한 거칠기 요소 형상의 영향 평가되었다. VOF 방법을 사용하여 자유 표면 흐름을 시뮬레이션하고 초기에 3개의 난류 모델 RNG, k-ɛ 및 kω를 검증에 사용하고 이를 검토한 후 RNG 방법을 사용하여 다른 모델을 시뮬레이션했습니다. 1- 수치 결과에서 얻은 부드러운 경사 방울의 하류 상대 깊이는 실험실 데이터와 매우 좋은 상관 관계가 있으며 원통형 요소가 장착 된 경사 방울의 상대 에지 깊이 값이 가장 높았습니다. 2- 하류 상대깊이는 임계상대깊이가 증가함에 따라 상승하는 경향을 나타내어 박쥐형 요소를 구비한 경사낙하와 완만한 경사낙하가 각각 하류상대깊이가 가장 높고 가장 낮았다. 3- 하류 깊이의 증가로 인해 상대적 임계 깊이가 증가함에 따라 상대적 에너지 소산이 감소합니다. 한편, 가장 높은 에너지 소산은 박쥐 모양의 요소가 장착된 경사 낙하와 관련이 있으며 가장 낮은 에너지 소산은 부드러운 낙하와 관련이 있습니다. 삼각형, 원통형 및 박쥐 모양의 거친 요소가 장착된 드롭은 부드러운 드롭보다 각각 65%, 76% 및 85% 더 많은 흐름 에너지를 소산합니다. 4- 낙차의 경사면에 거친 요소를 적용하여 다운 스트림 Froude 수를 크게 줄여 4.7 ~ 7.5에서 1.45 ~ 3.36까지의 모든 모델에서 Froude 수가 부드러운 낙하에 비해 감소했습니다. 또한, 다른 원소보다 부피가 작은 박쥐 모양의 거칠기의 부피로 인해 이러한 유형의 거칠기를 사용하는 것이 경제적입니다.

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    Figure 6. Evolution of melt pool in the overhang region (θ = 45°, P = 100 W, v = 1000 mm/s, the streamlines are shown by arrows).

    Experimental and numerical investigation of the origin of surface roughness in laser powder bed fused overhang regions

    레이저 파우더 베드 융합 오버행 영역에서 표면 거칠기의 원인에 대한 실험 및 수치 조사

    Shaochuan Feng,Amar M. Kamat,Soheil Sabooni &Yutao PeiPages S66-S84 | Received 18 Jan 2021, Accepted 25 Feb 2021, Published online: 10 Mar 2021

    ABSTRACT

    Surface roughness of laser powder bed fusion (L-PBF) printed overhang regions is a major contributor to deteriorated shape accuracy/surface quality. This study investigates the mechanisms behind the evolution of surface roughness (Ra) in overhang regions. The evolution of surface morphology is the result of a combination of border track contour, powder adhesion, warp deformation, and dross formation, which is strongly related to the overhang angle (θ). When 0° ≤ θ ≤ 15°, the overhang angle does not affect Ra significantly since only a small area of the melt pool boundaries contacts the powder bed resulting in slight powder adhesion. When 15° < θ ≤ 50°, powder adhesion is enhanced by the melt pool sinking and the increased contact area between the melt pool boundary and powder bed. When θ > 50°, large waviness of the overhang contour, adhesion of powder clusters, severe warp deformation and dross formation increase Ra sharply.

    레이저 파우더 베드 퓨전 (L-PBF) 프린팅 오버행 영역의 표면 거칠기는 형상 정확도 / 표면 품질 저하의 주요 원인입니다. 이 연구 는 오버행 영역에서 표면 거칠기 (Ra ) 의 진화 뒤에 있는 메커니즘을 조사합니다 . 표면 형태의 진화는 오버행 각도 ( θ ) 와 밀접한 관련이있는 경계 트랙 윤곽, 분말 접착, 뒤틀림 변형 및 드로스 형성의 조합의 결과입니다 . 0° ≤  θ  ≤ 15° 인 경우 , 용융풀 경계의 작은 영역 만 분말 베드와 접촉하여 약간의 분말 접착이 발생하기 때문에 오버행 각도가 R a에 큰 영향을 주지 않습니다 . 15° < θ 일 때  ≤ 50°, 용융 풀 싱킹 및 용융 풀 경계와 분말 베드 사이의 증가된 접촉 면적으로 분말 접착력이 향상됩니다. θ  > 50° 일 때 오버행 윤곽의 큰 파형, 분말 클러스터의 접착, 심한 휨 변형 및 드 로스 형성이 Ra 급격히 증가 합니다.

    KEYWORDS: Laser powder bed fusion (L-PBF), melt pool dynamics, overhang region, shape deviation, surface roughness

    1. Introduction

    레이저 분말 베드 융합 (L-PBF)은 첨단 적층 제조 (AM) 기술로, 집중된 레이저 빔을 사용하여 금속 분말을 선택적으로 융합하여 슬라이스 된 3D 컴퓨터 지원에 따라 층별로 3 차원 (3D) 금속 부품을 구축합니다. 설계 (CAD) 모델 (Chatham, Long 및 Williams 2019 ; Tan, Zhu 및 Zhou 2020 ). 재료가 인쇄 층 아래에 ​​존재하는지 여부에 따라 인쇄 영역은 각각 솔리드 영역 또는 돌출 영역으로 분류 될 수 있습니다. 따라서 오버행 영역은 고체 기판이 아니라 분말 베드 바로 위에 건설되는 특수 구조입니다 (Patterson, Messimer 및 Farrington 2017). 오버행 영역은지지 구조를 포함하거나 포함하지 않고 구축 할 수 있으며, 지지대가있는 돌출 영역의 L-PBF는 지지체가 더 낮은 밀도로 구축된다는 점을 제외 하고 (Wang and Chou 2018 ) 고체 기판의 공정과 유사합니다 (따라서 기계적 강도가 낮기 때문에 L-PBF 공정 후 기계적으로 쉽게 제거 할 수 있습니다. 따라서지지 구조로 인쇄 된 오버행 영역은 L-PBF 공정 후 지지물 제거, 연삭 및 연마와 같은 추가 후 처리 단계가 필요합니다.

    수평 내부 채널의 제작과 같은 일부 특정 경우에는 공정 후 지지대를 제거하기가 어려우므로 채널 상단 절반의 돌출부 영역을 지지대없이 건설해야합니다 (Hopkinson and Dickens 2000 ). 수평 내부 채널에 사용할 수없는지지 구조 외에도 내부 표면, 특히 등각 냉각 채널 (Feng, Kamat 및 Pei 2021 ) 에서 발생하는 복잡한 3D 채널 네트워크의 경우 표면 마감 프로세스를 구현하는 것도 어렵습니다 . 결과적으로 오버행 영역은 (i) 잔류 응력에 의한 변형, (ii) 계단 효과 (Kuo et al. 2020 ; Li et al. 2020 )로 인해 설계된 모양에서 벗어날 수 있습니다 .) 및 (iii) 원하지 않는 분말 소결로 인한 향상된 표면 거칠기; 여기서, 앞의 두 요소는 일반적으로 mm 길이 스케일에서 ‘매크로’편차로 분류되고 후자는 일반적으로 µm 길이 스케일에서 ‘마이크로’편차로 인식됩니다.

    열 응력에 의한 변형은 오버행 영역에서 발생하는 중요한 문제입니다 (Patterson, Messimer 및 Farrington 2017 ). 국부적 인 용융 / 냉각은 용융 풀 내부 및 주변에서 큰 온도 구배를 유도하여 응고 된 층에 집중적 인 열 응력을 유발합니다. 열 응력에 의한 뒤틀림은 고체 영역을 현저하게 변형하지 않습니다. 이러한 영역은 아래의 여러 레이어에 의해 제한되기 때문입니다. 반면에 오버행 영역은 구속되지 않고 공정 중 응력 완화로 인해 상당한 변형이 발생합니다 (Kamat 및 Pei 2019 ). 더욱이 용융 깊이는 레이어 두께보다 큽니다 (이전 레이어도 재용 해되어 빌드 된 레이어간에 충분한 결합을 보장하기 때문입니다 [Yadroitsev et al. 2013 ; Kamath et al.2014 ]),응고 된 두께가 설계된 두께보다 크기 때문에형태 편차 (예 : 드 로스 [Charles et al. 2020 ; Feng et al. 2020 ])가 발생합니다. 마이크로 스케일에서 인쇄 된 표면 (R a 및 S a ∼ 10 μm)은 기계적으로 가공 된 표면보다 거칠다 (Duval-Chaneac et al. 2018 ; Wen et al. 2018 ). 이 문제는고형화 된 용융 풀의 가장자리에 부착 된 용융되지 않은 분말의 결과로 표면 거칠기 (R a )가 일반적으로 약 20 μm인 오버행 영역에서 특히 심각합니다 (Mazur et al. 2016 ; Pakkanen et al. 2016 ).

    오버행 각도 ( θ , 빌드 방향과 관련하여 측정)는 오버행 영역의 뒤틀림 편향과 표면 거칠기에 영향을 미치는 중요한 매개 변수입니다 (Kamat and Pei 2019 ; Mingear et al. 2019 ). θ ∼ 45 ° 의 오버행 각도 는 일반적으로지지 구조없이 오버행 영역을 인쇄 할 수있는 임계 값으로 합의됩니다 (Pakkanen et al. 2016 ; Kadirgama et al. 2018 ). θ 일 때이 임계 값보다 크면 오버행 영역을 허용 가능한 표면 품질로 인쇄 할 수 없습니다. 오버행 각도 외에도 레이저 매개 변수 (레이저 에너지 밀도와 관련된)는 용융 풀의 모양 / 크기 및 용융 풀 역학에 영향을줌으로써 오버행 영역의 표면 거칠기에 영향을줍니다 (Wang et al. 2013 ; Mingear et al . 2019 ).

    용융 풀 역학은 고체 (Shrestha 및 Chou 2018 ) 및 오버행 (Le et al. 2020 ) 영역 모두에서 수행되는 L-PBF 공정을 포함한 레이저 재료 가공의 일반적인 물리적 현상입니다 . 용융 풀 모양, 크기 및 냉각 속도는 잔류 응력으로 인한 변형과 ​​표면 거칠기에 모두 영향을 미치므로 처리 매개 변수와 표면 형태 / 품질 사이의 다리 역할을하며 용융 풀을 이해하기 위해 수치 시뮬레이션을 사용하여 추가 조사를 수행 할 수 있습니다. 거동과 표면 거칠기에 미치는 영향. 현재까지 고체 영역의 L-PBF 동안 용융 풀 동작을 시뮬레이션하기 위해 여러 연구가 수행되었습니다. 유한 요소 방법 (FEM)과 같은 시뮬레이션 기술 (Roberts et al. 2009 ; Du et al.2019 ), 유한 차분 법 (FDM) (Wu et al. 2018 ), 전산 유체 역학 (CFD) (Lee and Zhang 2016 ), 임의의 Lagrangian-Eulerian 방법 (ALE) (Khairallah and Anderson 2014 )을 사용하여 증발 반동 압력 (Hu et al. 2018 ) 및 Marangoni 대류 (Zhang et al. 2018 ) 현상을포함하는 열 전달 (온도 장) 및 물질 전달 (용융 흐름) 프로세스. 또한 이산 요소법 (DEM)을 사용하여 무작위 분산 분말 베드를 생성했습니다 (Lee and Zhang 2016 ; Wu et al. 2018 ). 이 모델은 분말 규모의 L-PBF 공정을 시뮬레이션했습니다 (Khairallah et al. 2016) 메조 스케일 (Khairallah 및 Anderson 2014 ), 단일 트랙 (Leitz et al. 2017 )에서 다중 트랙 (Foroozmehr et al. 2016 ) 및 다중 레이어 (Huang, Khamesee 및 Toyserkani 2019 )로.

    그러나 결과적인 표면 거칠기를 결정하는 오버행 영역의 용융 풀 역학은 문헌에서 거의 관심을받지 못했습니다. 솔리드 영역의 L-PBF에 대한 기존 시뮬레이션 모델이 어느 정도 참조가 될 수 있지만 오버행 영역과 솔리드 영역 간의 용융 풀 역학에는 상당한 차이가 있습니다. 오버행 영역에서 용융 금속은 분말 입자 사이의 틈새로 아래로 흘러 용융 풀이 다공성 분말 베드가 제공하는 약한 지지체 아래로 가라 앉습니다. 이것은 중력과 표면 장력의 영향이 용융 풀의 결과적인 모양 / 크기를 결정하는 데 중요하며, 결과적으로 오버행 영역의 마이크로 스케일 형태의 진화에 중요합니다. 또한 분말 입자 사이의 공극, 열 조건 (예 : 에너지 흡수,2019 ; Karimi et al. 2020 ; 노래와 영 2020 ). 표면 거칠기는 (마이크로) 형상 편차를 증가시킬뿐만 아니라 주기적 하중 동안 미세 균열의 시작 지점 역할을함으로써 기계적 강도를 저하시킵니다 (Günther et al. 2018 ). 오버행 영역의 높은 표면 거칠기는 (마이크로) 정확도 / 품질에 대한 엄격한 요구 사항이있는 부품 제조에서 L-PBF의 적용을 제한합니다.

    본 연구는 실험 및 시뮬레이션 연구를 사용하여 오버행 영역 (지지물없이 제작)의 미세 형상 편차 형성 메커니즘과 표면 거칠기의 기원을 체계적이고 포괄적으로 조사합니다. 결합 된 DEM-CFD 시뮬레이션 모델은 경계 트랙 윤곽, 분말 접착 및 뒤틀림 변형의 효과를 고려하여 오버행 영역의 용융 풀 역학과 표면 형태의 형성 메커니즘을 나타 내기 위해 개발되었습니다. 표면 거칠기 R의 시뮬레이션 및 단일 요인 L-PBF 인쇄 실험을 사용하여 오버행 각도의 함수로 연구됩니다. 용융 풀의 침몰과 관련된 오버행 영역에서 분말 접착의 세 가지 메커니즘이 식별되고 자세히 설명됩니다. 마지막으로, 인쇄 된 오버행 영역에서 높은 표면 거칠기 문제를 완화 할 수 있는 잠재적 솔루션에 대해 간략하게 설명합니다.

    The shape and size of the L-PBF printed samples are illustrated in Figure 1
    The shape and size of the L-PBF printed samples are illustrated in Figure 1
    Figure 2. Borders in the overhang region depending on the overhang angle θ
    Figure 2. Borders in the overhang region depending on the overhang angle θ
    Figure 3. (a) Profile of the volumetric heat source, (b) the model geometry of single-track printing on a solid substrate (unit: µm), and (c) the comparison of melt pool dimensions obtained from the experiment (right half) and simulation (left half) for a calibrated optical penetration depth of 110 µm (laser power 200 W and scan speed 800 mm/s, solidified layer thickness 30 µm, powder size 10–45 µm).
    Figure 3. (a) Profile of the volumetric heat source, (b) the model geometry of single-track printing on a solid substrate (unit: µm), and (c) the comparison of melt pool dimensions obtained from the experiment (right half) and simulation (left half) for a calibrated optical penetration depth of 110 µm (laser power 200 W and scan speed 800 mm/s, solidified layer thickness 30 µm, powder size 10–45 µm).
    Figure 4. The model geometry of an overhang being L-PBF processed: (a) 3D view and (b) right view.
    Figure 4. The model geometry of an overhang being L-PBF processed: (a) 3D view and (b) right view.
    Figure 5. The cross-sectional contour of border tracks in a 45° overhang region.
    Figure 5. The cross-sectional contour of border tracks in a 45° overhang region.
    Figure 6. Evolution of melt pool in the overhang region (θ = 45°, P = 100 W, v = 1000 mm/s, the streamlines are shown by arrows).
    Figure 6. Evolution of melt pool in the overhang region (θ = 45°, P = 100 W, v = 1000 mm/s, the streamlines are shown by arrows).
    Figure 7. The overhang contour is contributed by (a) only outer borders when θ ≤ 60° (b) both inner borders and outer borders when θ > 60°.
    Figure 7. The overhang contour is contributed by (a) only outer borders when θ ≤ 60° (b) both inner borders and outer borders when θ > 60°.
    Figure 8. Schematic of powder adhesion on a 45° overhang region.
    Figure 8. Schematic of powder adhesion on a 45° overhang region.
    Figure 9. The L-PBF printed samples with various overhang angle (a) θ = 0° (cube), (b) θ = 30°, (c) θ = 45°, (d) θ = 55° and (e) θ = 60°.
    Figure 9. The L-PBF printed samples with various overhang angle (a) θ = 0° (cube), (b) θ = 30°, (c) θ = 45°, (d) θ = 55° and (e) θ = 60°.
    Figure 10. Two mechanisms of powder adhesion related to the overhang angle: (a) simulation-predicted, θ = 45°; (b) simulation-predicted, θ = 60°; (c, e) optical micrographs, θ = 45°; (d, f) optical micrographs, θ = 60°. (e) and (f) are partial enlargement of (c) and (d), respectively.
    Figure 10. Two mechanisms of powder adhesion related to the overhang angle: (a) simulation-predicted, θ = 45°; (b) simulation-predicted, θ = 60°; (c, e) optical micrographs, θ = 45°; (d, f) optical micrographs, θ = 60°. (e) and (f) are partial enlargement of (c) and (d), respectively.
    Figure 11. Simulation-predicted surface morphology in the overhang region at different overhang angle: (a) θ = 15°, (b) θ = 30°, (c) θ = 45°, (d) θ = 60° and (e) θ = 80° (Blue solid lines: simulation-predicted contour; red dashed lines: the planar profile of designed overhang region specified by the overhang angles).
    Figure 11. Simulation-predicted surface morphology in the overhang region at different overhang angle: (a) θ = 15°, (b) θ = 30°, (c) θ = 45°, (d) θ = 60° and (e) θ = 80° (Blue solid lines: simulation-predicted contour; red dashed lines: the planar profile of designed overhang region specified by the overhang angles).
    Figure 12. Effect of overhang angle on surface roughness Ra in overhang regions
    Figure 12. Effect of overhang angle on surface roughness Ra in overhang regions
    Figure 13. Surface morphology of L-PBF printed overhang regions with different overhang angle: (a) θ = 15°, (b) θ = 30°, (c) θ = 45° and (d) θ = 60° (overhang border parameters: P = 100 W, v = 1000 mm/s).
    Figure 13. Surface morphology of L-PBF printed overhang regions with different overhang angle: (a) θ = 15°, (b) θ = 30°, (c) θ = 45° and (d) θ = 60° (overhang border parameters: P = 100 W, v = 1000 mm/s).
    Figure 14. Effect of (a) laser power (scan speed = 1000 mm/s) and (b) scan speed (lase power = 100 W) on surface roughness Ra in overhang regions (θ = 45°, laser power and scan speed referred to overhang border parameters, and the other process parameters are listed in Table 2).
    Figure 14. Effect of (a) laser power (scan speed = 1000 mm/s) and (b) scan speed (lase power = 100 W) on surface roughness Ra in overhang regions (θ = 45°, laser power and scan speed referred to overhang border parameters, and the other process parameters are listed in Table 2).

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    Abf - Three-dimensional view of the abbot from short to long to short

    Flow-3D 수치 모형을 이용한 파동 감소에 대한 규칙적인 레이아웃으로 식생 고도 변화 효과 연구

    세예드 아마드가 헤리 네 자드 1 , Mehdi Behdarvandi Askar  2 , 모하마드 안사리 고이 가르 3, 에산 파르시 4
    1 공학, 해안, 항만 및 & amp; 해양 구조물 _ 코람 샤르 해양 과학 기술 대학교
    2 코람 샤르 해양 과학 기술 대학교 해양 공학부 해양 구조학과
    3 이란 카라 지 테헤란 대학교 농업 및 천연 자원 대학 관개 및 매립 공학과.
    4 연구 전문가, Arvand Water and Energy Consulting Engineers Company, Ahvaz, Iran.

    Abstract

    The development of water waves through submerged and non-submerged vegetation is accompanied by a loss of energy through the resistive force of the vegetation, resulting in a decrease in wave height. Wave damping by vegetation is a function of cover characteristics such as geometry and structure, immersion ratio, density, hardness, and spatial arrangement, as well as wave conditions such as input wave height, duration, and wave direction. In the present study, the effect of geometric arrangement of vegetation with variable height on wave damping has been investigated using the Flow 3D numerical model. For this purpose, a channel with a length of 480 cm and a width of 10.8 cm, which has been previously used by Cox and Wu (2015) to study the effect of plant density with variable height on wave damping, is modeled. The operation of the three arrangements, including long to short arrangement, short to long arrangement, and zigzag arrangement, is examined under four different waves, all of which are linear waves. It should be noted that in this study, wave height is considered as an damping index. The results obtained by measuring the height of the waves at four different points along the channel show that the behavior of the waves in dealing with different arrangements follows a fixed pattern and also changes in the geometry of the vegetation can greatly lead to Increase the damping of the waves. The results show that a change in height arrangement can cause a change in damping of up to 7.1%.

    Keywords : Green belt , wave , geometric layout , vegetation

    물에 잠긴 초목과 물에 잠기지 않은 초목을 통한 물결의 발달은 초목의 저항력을 통한 에너지 손실을 동반하여 파고가 감소합니다. 식생에 의한 파동감쇠는 기하와 구조, 몰입도, 밀도, 경도, 공간배열 등 커버 특성과 입력파동 높이, 지속시간, 파동방향 등의 파동조건의 함수입니다.

    본 연구에서는 Flow 3D 수치 모델을 사용하여 가변 높이 식물이 파동 댐핑에 미치는 기하학적 배치가 조사되었습니다. 이를 위해 Cox와 Wu (2015)가 이전에 파동 댐핑에 대한 가변 높이의 발전소 밀도가 미치는 영향을 연구하기 위해 사용한 길이 480cm, 폭 10.8cm의 채널을 모델링합니다.

    장파에서 단파, 단파에서 장파까지, 지그재그 배열을 포함한 세 가지 배열의 작동은 4개의 다른 파장에서 조사됩니다. 모두 선형파입니다.

    본 연구에서는 파고가 감쇠 지수로 간주된다는 점에 유의해야 합니다.

    채널을 따라 네 곳의 서로 다른 지점에서 파도의 높이를 측정하여 얻은 결과는 다른 배열을 다루는 파도의 동작이 고정된 패턴을 따르며 또한 초목의 기하학적인 변화가 파도의 감쇠를 증가 시키는 것으로 크게 이어질 수 있다는 것을 보여줍니다.

    결과는 높이 배열의 변화가 최대 7.1%의 댐핑 변화를 일으킬 수 있음을 보여줍니다.

    Figure 1 - Geometry used by Cox and Wu (2015) to study the effect of plant density on wave damping
    Figure 1 – Geometry used by Cox and Wu (2015) to study the effect of plant density on wave damping
    Figure 2 - Schematic of Erie wave
    Figure 2 – Schematic of Erie wave
    Abf - Three-dimensional view of the abbot from short to long to short
    Abf – Three-dimensional view of the abbot from short to long to short

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    Figure 4. Structure of artificial neural network [37]

    Turbulent Flow Modeling at Tunnel Spillway Concave Bends and Prediction of Pressure using Artificial Neural Network

    터널 배수로 오목 굴곡에서 난류 유동 모델링 인공 신경망을 이용한 압력 예측 및 예측

    Zeinab Bashari Moghaddam 1
    Hossein Mohammad Vali Samani2
    Seyed Habib Mousavi Jahromi 3

    Abstract

    터널 배수로는 높은 자유 표면 유속이 설정되는 배수로 유형 중 하나입니다. 회전 가속과 난류 흐름의 불규칙성으로 인해 오목한 수직 굽힘에서 압력이 증가합니다. 물리적 모델은 이 현상을 분석하는 가장 좋은 도구입니다.

    모든 실제 프로토 타입 상태 분석을 포괄하는 데 필요한 물리적 모델의 수가 너무 많아 배치 및 비용 측면에서 비실용적입니다. 따라서 FLOW-3D 소프트웨어는 가능한 모든 실제 대안을 포괄하는 오목한 굴곡 터널의 난류 흐름 데이터베이스를 분석하고 생성하기 위해 선택되었습니다.

    이 소프트웨어는 방전과 형상이 다른 다양한 터널을 시뮬레이션했습니다. 수치 결과는 Alborz Dam 터널 배수로의 건설 된 물리적 모델의 실험 결과로 검증되었으며 만족스러운 동의를 얻었습니다. 차원 분석은 문제의 관련 변수를 차원 없는 매개 변수로 그룹화하는 데 사용됩니다.

    이러한 매개 변수는 인공 신경망 시뮬레이션에 사용됩니다. 결과는 Flow-3D 소프트웨어로 얻은 무 차원 매개 변수와 신경망에 의해 예측된 변수 사이의 상관 계수 R2 = 0.95를 보여 주었으며, 이와 관련하여 난류 모델링을 통해 얻은 데이터베이스를 기반으로 한 인공 신경망이 결론을 내릴 수있었습니다. 압력 예측을 위한 강력한 도구입니다.

    Keywords: Flow-3D, Tunnel spillway concave bend, Numerical simulation, Turbulent flow,
    Artificial neural network

    본문 내용 생략 : 본문 내용은 내용 하단부에 첨부된 본문 링크를 참조하시기 바랍니다.

    Figure 1. Flow in a concave curvature
    Figure 1. Flow in a concave curvature
    Figure 2. Flow in the curvature of the flip bucket
    Figure 2. Flow in the curvature of the flip bucket
    Figure 3. The location of piezometers on the bed of the concave curvature of tunnel spillway in Alborz Dam
    Figure 3. The location of piezometers on the bed of the concave curvature of tunnel spillway in Alborz Dam
    Figure 4. Structure of artificial neural network [37]
    Figure 4. Structure of artificial neural network [37]
    Figure 5. Correlation coefficient of the Neural Network simulation and Flow-3D in the training
stage
    Figure 6. Correlation coefficient of the Neural Network simulation and Flow-3D in the validation stage
    Figure 6. Correlation coefficient of the Neural Network simulation and Flow-3D in the validation stage
    Figure 7. Comparison 0f the Simulated Neural Network and Flow-3D Results of the validation stage
    Figure 7. Comparison 0f the Simulated Neural Network and Flow-3D Results of the validation stage
    Figure 8. Correlation coefficient of the Flow-3D numerical results and Equation (1)
    Figure 8. Correlation coefficient of the Flow-3D numerical results and Equation (1)
    Figure 9. Correlation coefficient of the Flow-3D numerical results and Equation (2)
    Figure 9. Correlation coefficient of the Flow-3D numerical results and Equation (2)
    Figure 10. Correlation coefficient of the Flow-3D numerical results and Equation (3)
    Figure 10. Correlation coefficient of the Flow-3D numerical results and Equation (3)

    현재 연구에서 FLOW-3D 소프트웨어는 처음에 다양한 크기와 배출의 터널 배수로에서 난류 흐름을 시뮬레이션하는데 사용되었습니다. 결과는 이란 에너지부 물 연구소에서 제공한 Alborz 저장 댐에서 얻은 실제 데이터와 비교하여 검증되었습니다.

    시뮬레이션에는 다양한 난류 모델이 사용되었으며 RNG 방법이 관찰된 실제 결과와 가장 잘 일치하는 것으로 나타났습니다. 직경이 3 ~ 15m 인 다양한 터널 배수로, 곡률 반경 3 개, 거의 모든 실제 사례를 포괄하는 3개의 배출이 시뮬레이션에 사용되었습니다.

    차원 분석을 사용하여 무 차원 매개 변수를 생성하고 문제의 변수 수를 줄였으며 마지막으로 두 개의 주요 무 차원 그룹이 결정되었습니다. 이러한 무 차원 변수 간의 관계를 얻기 위해 신경망을 사용하고 터널 배수로의 오목한 굴곡에서 압력 예측 단계에서 0.95의 상관 계수를 얻었습니다.

    압력 계산 결과는 다른 일반적인 방법으로 얻은 결과와 비교되었습니다. 비교는 신경망 결과가 훨씬 더 정확하고 배수로 터널의 오목한 곡률에서 압력을 예측하는 강력한 도구로 간주 될 수 있음을 나타냅니다.

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    Figure 1. Geometries and bed topography settings of the nine computational fluid dynamics (CFD) simulations with channel curvature (C) changed from 0.77 to 0

    The Straightening of a River Meander Leads to Extensive Losses in Flow Complexity and Ecosystem Services

    Abstract

    하천 복원 노력을 지원하기 위해 우리는 하천 파괴 속도를 늦출 필요가 있습니다. 이 연구는 하천 곡률 보호를 위해 구불 구불 한 하천이 곧게 펴질 때 수리적 복잡성 손실에 대한 자세한 설명을 제공합니다.

    전산 유체 역학 (CFD) 모델링을 사용하여 채널 곡률 (C)이 잘 확립된 사행 굽힘 (C = 0.77)에서 곡률이 없는 직선 채널 (C = 0)로 저하되는 9 개의 시뮬레이션에서 유동 역학의 차이를 문서화했습니다.

    공변량을 제어하고 수리적 복잡성에 대한 손실률을 늦추기 위해 각 9 개 채널 구현은 동등한 베드 형태 지형을 가졌습니다. 분석된 수력학적 변수에는 흐름 표면 고도, 흐름 방향 및 횡단 단위 배출, 흐름 방향, 가로 방향 및 수직 방향의 유속, 베드 전단 응력, 흐름 함수 및 채널 베드에서의 수직 저 유량 유속 비율이 포함되었습니다.

    수력 복잡성의 손실은 처음에 수로를 C = 0.77에서 C = 0.33 (즉, 수로의 반경이 수로 폭의 3 배임) 할 때 점차적으로 발생했으며, 추가 직선화는 수력 복잡성에 대한 급속한 손실을 초래했습니다.

    다른 연구에서는 수리적 복잡성이 중요한 하천 서식지를 제공하고 생물 다양성과 양의 상관 관계가 있음을 보여주었습니다. 이 연구는 강을 풀 때 수력학적 복잡성이 점진적으로 사라졌다가 빠르게 사라지는 방법을 보여줍니다.

    To assist river restoration efforts we need to slow the rate of river degradation. This study provides a detailed explanation of the hydraulic complexity loss when a meandering river is straightened in order to motivate the protection of river channel curvature. We used computational fluid dynamics (CFD) modeling to document the difference in flow dynamics in nine simulations with channel curvature (C) degrading from a well-established tight meander bend (C = 0.77) to a straight channel without curvature (C = 0). To control for covariates and slow the rate of loss to hydraulic complexity, each of the nine-channel realizations had equivalent bedform topography. The analyzed hydraulic variables included the flow surface elevation, streamwise and transverse unit discharge, flow velocity at streamwise, transverse, and vertical directions, bed shear stress, stream function, and the vertical hyporheic flux rates at the channel bed. The loss of hydraulic complexity occurred gradually when initially straightening the channel from C = 0.77 to C = 0.33 (i.e., the radius of the channel is three-times the channel width), and additional straightening incurred rapid losses to hydraulic complexity. Other studies have shown hydraulic complexity provides important riverine habitat and is positively correlated with biodiversity. This study demonstrates how hydraulic complexity can be gradually and then rapidly lost when unwinding a river, and hopefully will serve as a cautionary tale.

    Figure 1. Geometries and bed topography settings of the nine computational fluid dynamics (CFD) simulations with channel curvature (C) changed from 0.77 to 0
    Figure 1. Geometries and bed topography settings of the nine computational fluid dynamics (CFD) simulations with channel curvature (C) changed from 0.77 to 0
    Figure 2. Flow surface elevation (h) normalized by H at C = 0.77, C = 0.33, and C = 0 conditions. n denotes the lateral coordination with n = 0 at channel center and B denotes the channel width.
    Figure 2. Flow surface elevation (h) normalized by H at C = 0.77, C = 0.33, and C = 0 conditions. n denotes the lateral coordination with n = 0 at channel center and B denotes the channel width.
    Figure 3. Normalized flow surface profiles for the nine simulations at the point bar apex 1.5 s/B. The insert plot shows the second order derivative of normalized flow surface elevation in the transverse direction, Fh00(n/B), which gives the convexity or concavity of the surface profile curves.
    Figure 3. Normalized flow surface profiles for the nine simulations at the point bar apex 1.5 s/B. The insert plot shows the second order derivative of normalized flow surface elevation in the transverse direction, Fh00(n/B), which gives the convexity or concavity of the surface profile curves.
    Figure 4. Streamwise unit discharge qs/UH for channel curvature C = 0.77, 0.33, and 0 conditions.
    Figure 4. Streamwise unit discharge qs/UH for channel curvature C = 0.77, 0.33, and 0 conditions.
    Figure 5. Transverse unit discharge qn/UH for channel curvature C = 0.77, 0.33, and 0 conditions.
    Figure 5. Transverse unit discharge qn/UH for channel curvature C = 0.77, 0.33, and 0 conditions.

    Reference : https://www.mdpi.com/2073-4441/12/6/1680

    Figure 9. Distribution of river channel bed shear Cf for channel curvature C = 0.77, 0.33, and 0 conditions.
    Figure 9. Distribution of river channel bed shear Cf for channel curvature C = 0.77, 0.33, and 0 conditions.
    Figure 10. Normalized vertical hyporheic flux vzbed/U at 2 mm below sediment surface for channel curvature C = 0.77, 0.33, and 0 conditions. Positive indicates upwelling of groundwater into the river channel.
    Figure 10. Normalized vertical hyporheic flux vzbed/U at 2 mm below sediment surface for channel curvature C = 0.77, 0.33, and 0 conditions. Positive indicates upwelling of groundwater into the river channel.
    Figure 12. Transverse stream function distribution ψ/UBH reveals the secondary circulation of transverse flow cells rotating at the meander apex 1.5 s/B for channel curvature C = 0.77 (A), C = 0.33 (B), and C = 0 (C), with positive values representing clockwise rotation direction when facing upstream, and negative values representing counter-clockwise rotation when facing upstream.
    Figure 12. Transverse stream function distribution ψ/UBH reveals the secondary circulation of transverse flow cells rotating at the meander apex 1.5 s/B for channel curvature C = 0.77 (A), C = 0.33 (B), and C = 0 (C), with positive values representing clockwise rotation direction when facing upstream, and negative values representing counter-clockwise rotation when facing upstream.

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    Figure 12 Experimental set-up of particle image velocimetry (PIV) system.

    A comparison study between CFD analysis and PIV technique for velocity distribution over the Standard Ogee crested spillways

    Rizgar Ahmed Karim 1Jowhar Rasheed Mohammed 2Affiliations expand

    Free PMC article

    Abstract

    실험 및 수치 모델을 사용하여 표준 Ogee-crested 여수로에서 유속, 평균 속도, 수직 속도 분포 및 최대 속도 dm이 발생하는 위치를 비교하기 위해 포괄적인 연구가 수행되었습니다. 미국 육군 공병대 (USACE)의 사양에 따라 rigid foam으로 5 가지 다른 모델이 제작되었습니다.

    유동의 속도는 0.50, 1.00 및 1.33의 다른 비 차원 수두 비 H/Hd를 갖는 모든 모델에 대해 모델의 하류 곡선을 따라 기록되었습니다. 입자 이미지 유속계 (PIV)를 사용하여 유속을 측정했습니다. 속도 분포는 Matlab 코드를 사용하여 캡처된 일련의 이미지를 분석하여 얻었습니다.

    시판되는 CFD (Computational Fluid Dynamics) 소프트웨어 패키지인 Flow-3D가 실험 모델 설정을 모델링하는데 사용되었습니다. Flow-3D는 레이놀즈 평균 Navier-Stokes 방정식을 분석하고 배수로 흐름 분석 분야에서 사용하기 위해 널리 검증되었습니다.

    수치와 실험의 최대 차이는 수두비의 모든 값에 대해 6.2 %를 초과하지 않는 평균 속도 값을 나타냅니다. PIV 기법에 의해 기록 된 최대 속도의 보간된 값은 수치적으로 계산 된 값보다 작습니다.

    낮은 d m 위치에서 이 지역 간의 백분율 차이는 -8.65 %에 이릅니다. 상위 위치는 2.87 %입니다. 수직 위치 (d m)는 상류 수두가 증가하면 아래쪽 위치로 떨어지고 배수로 축으로부터의 거리가 선형으로 감소합니다.

    A comprehensive study was performed to compare flow rate, mean velocity, vertical velocity distribution, and locations where the maximum velocity, d m , occurs on standard Ogee-crested spillways using experimental and numerical models. Five different models were constructed from rigid foam according to the specifications of the United States Army Corps of Engineers (USACE). The velocity of the flow was recorded along the downstream curve of the model for all models with different non-dimensional head ratios H/H d of 0.50, 1.00, and 1.33. Particle Image Velocimetry (PIV) was used to measure the flow velocities. Velocity distributions were obtained by analyzing a series of captured images using Matlab codes. A commercially available Computational Fluid Dynamics (CFD) software package, Flow-3D, was used for modelling the experimental model setups. Flow-3D analyzes the Reynolds-averaged Navier-Stokes equations and is widely verified for use in the field of spillway flow analysis. The maximum difference between numerical and experimental results in mean velocity values that do not exceed 6.2% for all values of head ratios. The interpolated values of recorded maximum velocity by the PIV technique are smaller than those values numerically computed. In the lower d m locations, the percent difference between these regions reaches -8.65%; the upper locations are 2.87%. The vertical location (d m ) drops to the lower location when the upstream head increases, and the distance from the spillway axis decreases linearly.

    Keywords: Applied fluid mechanics; Civil engineering; Computational fluid dynamics; Finite element methods; Hydraulics; Hydrodynamics; Ogee-crested spillway; Particle image velocimetry; Physical model; Velocity distribution.

    Figure 1 Dimensions of standard ogee-crested spillway, (a) dimensions and flow parameters, and (b) detail of upstream quadrant.
    Figure 1 Dimensions of standard ogee-crested spillway, (a) dimensions and flow parameters, and (b) detail of upstream quadrant.
    Figure 2 Side view of the experimental model.
    Figure 2 Side view of the experimental model.
    Figure 3 Laboratory setup.
    Figure 3 Laboratory setup.
    Figure 4 Discharge Coefficients of Experimental and Numerical results plotted together with USACE-WES Published Data, (a) for model No. 1, (b) for model No. 3.
    Figure 4 Discharge Coefficients of Experimental and Numerical results plotted together with USACE-WES Published Data, (a) for model No. 1, (b) for model No. 3.
    Figure 5 Rating curves of theoretical discharge and flowmeter reading.
    Figure 5 Rating curves of theoretical discharge and flowmeter reading.
    Figure 6 Mesh geometry.
    Figure 6 Mesh geometry.
    Figure 7 Numerical model geometry.
    Figure 7 Numerical model geometry.
    Figure 8 Mesh geometry.
    Figure 8 Mesh geometry.
    Figure 9 Boundary conditions of the Modeling.
    Figure 9 Boundary conditions of the Modeling.
    Figure 10 Normalized discharge comparison.
    Figure 10 Normalized discharge comparison.
    Figure 11 Relative percent difference in discharge.
    Figure 11 Relative percent difference in discharge.
    Figure 12 Experimental set-up of particle image velocimetry (PIV) system.
    Figure 12 Experimental set-up of particle image velocimetry (PIV) system.
    Figure 13 (a) Spillway Model setup, (b) Raw Image, and (c) Post-processed Image.
    Figure 13 (a) Spillway Model setup, (b) Raw Image, and (c) Post-processed Image.
    Figure 14 Cross-correlation algorithm.
    Figure 14 Cross-correlation algorithm.
    Figure 15 Velocity field and streamlines measured by PIV and simulated with CFD for flow over ogee spillway, (a) model no. 1 and (b) model no. 3.
    Figure 15 Velocity field and streamlines measured by PIV and simulated with CFD for flow over ogee spillway, (a) model no. 1 and (b) model no. 3.
    Figure 16 Comparison of head-mean velocity of experimental and numerical analysis for all models.
    Figure 16 Comparison of head-mean velocity of experimental and numerical analysis for all models.
    Figure 17 Sketch of velocity profile and its position for model no. 1.
    Figure 17 Sketch of velocity profile and its position for model no. 1.
    Figure 18 Vertical Distribution of Velocity for Different Runs of model No. 1.
    Figure 18 Vertical Distribution of Velocity for Different Runs of model No. 1.
    Figure 19 Vertical location of maximum velocity.
    Figure 19 Vertical location of maximum velocity.

    Conclusions

    이 연구는 최대 속도를위한 수직 위치를 선택하는 동시에 설계 헤드보다 높은 수두에 대해 제어 된 환경에서 Ogee 볏이있는 배수로의 흐름을 더 잘 이해하는 데 기여하기 위해 수행되었습니다. 여기에서 5 개의 실험 모델이 USACE-WES 표준 여수로 모양에 따라 설계 및 제작되었으며 실험실 수로에서 테스트되었습니다. PIV 카메라는 유속을 측정하는 데 사용되었으며 CFD 소프트웨어는 실험 설정을 모델링하는 데 사용되었습니다.

    수치 결과는 실험과 잘 일치했습니다. 등급 곡선 결과는 수치 값과 PIV 값의 최대 차이가 평균 속도 값이 모든 수 두비 값에 대해 5.59 %를 초과하지 않음을 나타냅니다. 정규화 된 WES 공개 데이터와 실험 결과 간의 최대 차이는 -7.54 %였습니다.

    PIV 카메라로 기록 된 평균 속도는 CFD 모델에서 수치 적으로 분석되었으며, 비교 결과는 수치 데이터와 실험 데이터가 잘 일치 함을 보여줍니다. 최대 차이는 모든 헤드 비율에 대해 6.54 %를 초과하지 않습니다.

    속도 비 (v / vmax.)의 실험적 보간 데이터는 dm 이하의 위치에서 수치 적으로 계산 된 데이터보다 작지만 반대로 dm보다 높은 위치에 있습니다. 이 현상은 수치 모델링에서 표면 거칠기를 고려하지 않았기 때문에 발생합니다. 방수로 모델의 표면은 매끄러운 표면으로 가정되었습니다. 최대 속도가 발생하는 수직 위치는 상류 수두가 증가함에 따라 낮은 위치에 있습니다. 위치는 방수로 축으로부터의 거리에 따라 거의 선형 적으로 증가합니다.

    필요한 메시 미세 조정 및 구성은 원하는 데이터 유형에 따라 다릅니다. 일반적으로 속도 프로파일을 모델링하는 데는 0.33cm 메쉬로 충분했으며 더 작은 그리드 크기도 평가했지만 변경 사항은 없습니다.

    실험적 모델링과 수치 적 모델링의 비교와 관련하여 실험적 모델링이 여전히 더 확립되어 있음이 분명합니다. CFD 모델은 실험 모델보다 속도와 난류에 대해 더 자세한 정보를 제공 할 수 있지만 경우에 따라 더 경제적 일 수 있습니다.

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    Figure 1. Experimental flume used (a) Side view of the flume; (b) Pool detail.

    Modelling of Pool-Type Fishways Flows: Efficiency and Scale Effects Assessment

    by Ana L. Quaresma *OrcID andAntónio N. PinheiroOrcID
    CERIS—Civil Engineering for Research and Innovation for Sustainability, Instituto Superior Técnico (IST), Universidade de Lisboa, 1049-001 Lisboa, Portugal*
    Author to whom correspondence should be addressed.
    Academic Editor: Bommanna Krishnappan
    Water 2021, 13(6), 851; https://doi.org/10.3390/w13060851
    Received: 16 January 2021 / Revised: 8 March 2021 / Accepted: 18 March 2021 / Published: 20 March 2021
    (This article belongs to the Special Issue Ecohydraulics of Pool-Type Fishways)

    Abstract

    이 연구에서는 전산 유체 역학 (CFD) 소프트웨어 (FLOW-3D®)를 사용하여 바닥 오리피스가 있는 풀형 어로에서 흐름의 3D 수치 모델링을 수행했습니다. 수치 결과는 음향 도플러 속도계 (ADV) 및 입자 이미지 속도계 (PIV) 측정에서 얻은 실험 데이터와 비교되었습니다.

    흐름 깊이, 흐름 패턴, 수속, 난류 운동 에너지, Reynolds 수직 응력 및 바닥 구성 요소에 평행한 Reynolds 전단 응력과 같이 어로 효율에 영향을 미치는 여러 유체 역학적 변수를 정성 및 정량적으로 비교했습니다.

    수치 모델은 복잡한 유동장을 정확하게 재현하여 수치 모델 예측과 분석 된 변수에 대한 실험 데이터 사이에 전반적으로 좋은 일치를 보여줍니다. 분석중인 모든 매개 변수에 대한 수치 모델 검증 수행의 중요성이 강조되었습니다.

    또한 프로토 타입 어로의 업 스케일 된 수치 모델을 실행하여 스케일링 효과를 분석했습니다. 스케일 효과의 증거없이 실제 모델과 프로토 타입 치수 모두에 대해 유사한 정확도로 모델을 수행했습니다.

    현재 연구는 CFD 모델 (즉, FLOW-3D®)이 새로운 수영장 유형 어로 형상을 위한 적절하고 효율적인 설계 및 분석 도구로 사용될 수 있으며 물리적 모델 테스트를 줄이고 보완 할 수 있다고 결론지었습니다.

    In this study, the 3D numerical modelling of flow in a pool-type fishway with bottom orifices was performed using computational fluid dynamics (CFD) software (FLOW-3D®). Numerical results were compared with experimental data obtained from acoustic Doppler velocimetry (ADV) and particle image velocimetry (PIV) measurements. Several hydrodynamic variables that influence fishways efficiencies, such as flow depths, flow patterns, water velocity, turbulent kinetic energy, Reynolds normal stresses, and Reynolds shear stress parallel to the bottom component, were qualitatively and quantitatively compared. The numerical model accurately reproduced the complex flow field, showing an overall good agreement between the numerical model predictions and the experimental data for the analysed variables. The importance of performing a numerical model validation for all the parameters under analyses was highlighted. Additionally, scaling effects were analysed by running an upscaled numerical model of the prototype fishway. The model performed with similar accuracy for both physical model and prototype dimensions with no evidence of scale effects. The present study concludes that CFD models (namely FLOW-3D®) may be used as an adequate and efficient design and analysis tool for new pool-type fishways geometries, reducing and complementing physical model testing.Keywords: pool-type fishways3D numerical modellingLESscale effectsflow patternsCFD model assessment

    Introduction

    강의 종단 연결성을 복원하는 것은 담수 생태계의 회복에있어 여전히 중요한 문제입니다 [1,2]. 잘 설계되고 건설된 경우 어로는 물고기가 댐과 둑을 지나 계속 이동할 수 있는 경로를 제공합니다.

    물고기 통과 효율성에 대한 검토에서 Noonan et al. [3]은 기존의 많은 어로의 설계 특성이 어종의 요구를 적절하게 충족시키지 못했지만, 풀형 어로가 모든 어류 그룹에 대해 가장 높은 효율성을 보여 주었다는 것을 발견했습니다.
    여러 어종에 적합한 수영 조건을 제공하는 것은 어항의 흐름과 난류 패턴이 성공에 중요한 역할을 하기 때문에 다소 어려운 일입니다 [2,4,5,6,7,8,9,10,11,12].

    물리적 모델링은 풀형 유형 어로의 유체 역학을 연구하기 위한 주요 접근 방식이었습니다 (예 : [13,14,15,16,17,18,19,20,21,22]). 그러나 물리적 실험은 비용과 시간이 많이 소요됩니다. 따라서 컴퓨터 기술의 발전으로 인해 물리적 모델 테스트를 줄이기 위해 복잡한 기하학적 구조를 가진 유압 구조의 흐름 패턴을 분석하는 데 전산 유체 역학 (CFD) 3 차원 (3D) 모델이 점점 더 많이 사용되고 있습니다 [23,24].

    따라서 이러한 모델은 어로 유체 역학 연구 및 효율적인 어로 설계에 필수적인 역할을 할 수 있습니다.
    어로에 대한 수치 모델링 연구는 주로 수직 슬롯 어로에 초점을 맞추고 있습니다 [12,25,26,27,28,29,30,31,32,33,34,35,36,37]. 수영장의 주요 부분에서 수직 슬롯 어로 흐름은 거의 2 차원 (2D)이고 수직 속도 구성 요소가 수평 요소 [26]보다 훨씬 작기 때문에 이러한 연구의 대부분은 2D 모델을 사용했습니다.

    바닥 오리피스가있는 수영장 유형 어로에서는 흐름이 매우 복잡하고 3D이므로 정확한 유동장 특성화를 얻기 위해 3D 모델을 사용해야합니다. 이 어로 구성을 모델링하는 것은 높은 속도 구배, 높은 와도 및 높은 전단 영역을 포함하기 때문에 다소 어렵습니다.

    이 연구에서는 FLOW-3D® (Flow Science, Inc., Santa Fe, NM, USA)를 사용하여 바닥 오리피스가 있는 수영장 유형 어로의 3D 수치 시뮬레이션을 수행하여 흐름 깊이, 속도 및 난류 패턴을 예측하는 능력을 평가했습니다. .

    최근 몇 년 동안 실내에 가까운 프로토 타입 수영장 형 어로가 사이프 린드 종의 행동과 움직임을 연구하는데 사용되었습니다 [1,7,8,11,38,39,40,41,42,43]. Silva et al. [38]은 노치, 급락 및 스트리밍에 대한 두 가지 다른 유동 체제와 관련하여 조정 가능한 치수를 가진 침수된 오리피스와 표면 노치의 동시 존재에 대한 Iberian barbel Luciobarbus bocagei (Steindachner, 1864)의 반응을 평가했습니다.

    이 연구의 결과는 이베리아 바벨이 어로를 협상하기 위해 오리피스 (76 %)를 선호했으며 어로에 들어가는 데 걸리는 시간도 오리피스에 비해 훨씬 적다는 것을 보여주었습니다.

    Silva et al. [39] 오프셋 및 직선 오리피스가있는 수영장 유형 어로의 이베리아 바벨에 대한 적합성을 테스트했습니다. 이 연구는 오프셋 구성이 직선 오리피스 레이아웃 (28 %)에 비해 물고기 통과 성공률 (68 %)이 훨씬 더 높음을 발견했습니다. 어로를 성공적으로 협상하는 데 걸리는 시간도 오프셋 구성, 특히 작은 성인의 경우 훨씬 더 낮았습니다.

    이 연구에서는 유속과 난류 매개 변수가 물고기 수영 성능에 미치는 영향을 분석했습니다. 수영장의 유동장을 특성화하기 위해 음향 도플러 속도계가 사용되었습니다.

    이 연구의 결과에 따르면 레이놀즈 전단 응력은 어로 내 이베리아 미늘의 움직임에 가장 큰 영향을 미치는 매개 변수임이 입증되었습니다. Branco et al. [40] 두 가지 다른 흐름을 가진 오리피스와 노치가 있는 풀형 유형 어로에서 형태 학적 및 생태학적 특성이 다른 두 종, 바닥 지향 이베리아 바벨 Luciobarbus bocagei 및 물기둥 수영 자 Iberian chub Squalius pyrenaicus의 거동과 성능을 평가했습니다.

    풀의 유체 역학을 특성화하기 위해 음향 도플러 속도계가 사용되었습니다. 결과는 두 종 모두 흐름 흐름이있는 노치를 선호했으며 이 흐름 체제로 상류로 이동하는데 더 성공적이었습니다.
    이 연구에서는 이 시설의 1 : 2.5 스케일 어로 모델을 사용하여 Silva et al.에 의해 테스트된 바닥 오리피스 구성이 있는 풀형 유형 어로의 속도와 난류를 측정했습니다.

    [7,38] 효과가 입증된 바벨 사용. 2D 입자 이미지 속도계 (PIV) 시스템 및 음향 도플러 속도계 (ADV)를 사용하여 순간 속도의 광범위한 측정을 수행하고, 후 처리하고, 수치 모델 정확도를 평가하는 데 사용했습니다.

    Haque et al. [44] 대부분의 경우 수치 모델의 검증에 사용할 수있는 실험 데이터 세트에 높은 측정 오류가 있고 / 또는 측정 메시가 너무 거칠어 서 이들의 예측 기능을 올바르게 평가할 수없는 문제를 언급했습니다.

    모델. Blocken과 Gualtieri [23]는 검증 및 검증 연구가 필수적이며 CFD 연구를 검증하기위한 데이터를 제공하기 위해 고품질 실험이 필요하다고 언급합니다.

    Fuentes-Pérez et al. [35]는 특히 난류 메트릭에 대한 어로 연구에서 수치 모델 검증 데이터를 찾는 데 어려움을 언급합니다. 두 가지 측정 기술을 사용하고 상당한 양의 실험 데이터를 얻었기 때문에 이 연구에서는 이러한 문제를 극복했습니다.

    물리적 모델은 종종 Froude 수 유사성을 기반으로하며, 두 유사성 법칙을 모두 충족하는 데 어려움이있어 무시되는 레이놀즈 수 유사성입니다. 프로토 타입 레이놀즈 수가 일반적으로 훨씬 더 크기 때문에 레이놀즈 수 관련 스케일 효과가 도입될 수 있습니다.

    레이놀즈 수 증가는 속도 분포와 경계층 속성에 영향을 미칠 수 있습니다 [45]. 척도 효과를 평가하기 위해 수치 시뮬레이션을 사용할 수 있습니다 [46,47]. 따라서 본 연구에서는 바닥 오리피스 흐름이있는 풀형어도에 대한 스케일 효과를 분석하기 위해 두 가지 크기의 수치 모델을 개발했습니다.

    프로토 타입 치수의 대형 모델과 물리적 모델 치수의 스케일 된 소형 모델입니다. .
    바닥 오리피스가있는 수영장 형 어로의 유동장은 수직 슬롯 어로 (VSF)의 유동장보다 매우 3 차원 적이며 훨씬 더 복잡합니다. 이는 어로 수치 모델 검증에 대한 이전 연구에서 더 자주 고려 된 설계입니다 [26, 27,28,29,35].

    저자가 아는 한, 이것은 바닥 오리피스가있는 풀형 어로에 대한 최초의 CFD 연구이며, 여기에는 실험 속도 데이터와 풀형 어로에 대한 3 차원 수치 모델링 결과 간의 가장 광범위한 비교도 포함됩니다. 두 가지 다른 측정 기술 (PIV 및 ADV)이 사용되어 자세한 비교가 가능하고 이러한 유형의 유동장에 대한 CFD 시뮬레이션 결과에 대한 확신을 제공합니다.

    이 연구는 다른 어로 유형의 이전 수치 모델 연구에서 제시되지 않았던 난류 매개 변수를 포함하여 수치 모델 결과와 측정 간의 일치에 대한 통계적 테스트를 통해 정성적 비교 뿐만 아니라 상세한 정량적 비교도 제공합니다. 스케일 효과도 다룹니다.

    따라서 이 연구는 전 세계적으로 가장 많이 사용되는 풀 유형 어로의 CFD 모델 검증을 원활하게 할 것이며 [10] 설계자들의 사용을 장려 할 것입니다.
    또한 새로운 풀 유형 어로 형상을 위한 설계 도구로 CFD 모델 (즉, FLOW 3D®)을 사용하는 방법에 대해 설명합니다.

    Figure 1. Experimental flume used (a) Side view of the flume; (b) Pool detail.
    Figure 1. Experimental flume used (a) Side view of the flume; (b) Pool detail.
    Figure 2. Three dimensional representations of a pool showing the measurement planes and the acoustic Doppler velocimetry (ADV) measurement grid (a) measurement planes parallel to the flume bottom; (b) vertical measurement planes (ADV measurement grid is only shown in one plane).
    Figure 2. Three dimensional representations of a pool showing the measurement planes and the acoustic Doppler velocimetry (ADV) measurement grid (a) measurement planes parallel to the flume bottom; (b) vertical measurement planes (ADV measurement grid is only shown in one plane).
    Figure 3. Computational domain, showing Pool 3 mesh block.
    Figure 3. Computational domain, showing Pool 3 mesh block.
    Figure 4. Streamlines of time-averaged velocities (left: PIV; right: mesh Amodel): (a,b) plane 2 (z = 0.088 m); (c,d) plane 5 (y = 0.20 m).
    Figure 4. Streamlines of time-averaged velocities (left: PIV; right: mesh Amodel): (a,b) plane 2 (z = 0.088 m); (c,d) plane 5 (y = 0.20 m).
    Figure 5. Longitudinal variation of velocity components: (a,c,e) planes 1 and 6 intersection (y = 0.36 m and z = 0.04 m); (b,d,f) planes 2 and 5 intersection (y = 0.20 m and z = 0.088 m).
    Figure 5. Longitudinal variation of velocity components: (a,c,e) planes 1 and 6 intersection (y = 0.36 m and z = 0.04 m); (b,d,f) planes 2 and 5 intersection (y = 0.20 m and z = 0.088 m).
    Figure 6. Longitudinal variation of Reynolds normal stress components and Reynolds shear stress parallel to the bottom component: (a,c,e,g) planes 1 and 6 intersection (y = 0.36 m and z = 0.04m); (b,d,f,h) planes 2 and 5 intersection (y = 0.20 m and z = 0.088 m).
    Figure 6. Longitudinal variation of Reynolds normal stress components and Reynolds shear stress parallel to the bottom component: (a,c,e,g) planes 1 and 6 intersection (y = 0.36 m and z = 0.04m); (b,d,f,h) planes 2 and 5 intersection (y = 0.20 m and z = 0.088 m).

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    FLOW-3D 용어 사전 테이블

    FLOW-3D Glossary | FLOW-3D 용어 사전

    FLOW-3D 용어 사전 / 용어 설명

    FLOW-3D 용어 사전 테이블
    FLOW-3D 용어 사전 테이블

    FLOW-3D 용어 사전 / 용어 설명

    Drift Flux

    드리프트 모델은 밀도가 서로 다른 두 혼합 유체 구성 요소의 상대적 흐름을 설명합니다. 구성 요소는 상이 다를 수도 있고, 상이 같지만(불가침) 유체가 다를 수도 있습니다. 분산된 위상 입자 크기가 클 경우 드리프트 모델의 적용성에 대한 제한이 존재할 수 있습니다. 이러한 제한은 일반적으로 메쉬 셀 크기의 10% 미만으로 분산된 위상 입자 크기를 유지함으로써 방지할 수 있습니다.

    배플

    얇은 형상 조각을 나타내는데 사용되는 2 차원 개체입니다. 이들은 전처리기에 의해 셀면으로 이동되고 유체의 흐름을 부분적으로 또는 완전히 차단하는 역할을 합니다. 배플은 지정된 열 전달 계수를 가질 수 있으며 배플을 통과하는 양(플럭스 표면)을 측정하는 데 사용할 수 있습니다.

    Two-dimensional objects that are used to represent thin pieces of geometry. They are moved by the preprocessor to cell faces and act to partially, or completely block the flow of fluid. Baffles can have heat transfer coefficients specified and can be used to measure quantities that pass through them (a flux surface).

    경계 조건

    도메인의 범위에서 솔루션을 정의합니다. 경계 위치에서 흐름의 실제 상태를 나타내는 경계 조건을 선택하는 것이 중요합니다.

    Defines the solution at the extents of the domain. It is important to choose boundary conditions that represent the true condition of the flow at the boundary location.

    CFD

    CFD (Computational Fluid Dynamics)는 수치 솔루션을 통해 컴퓨터의 유체 흐름을 시뮬레이션 하는 유체 역학의 한 분야입니다.

    Computational Fluid Dynamics (CFD), the branch of fluid mechanics dedicated to simulating the flow of fluid on a computer via numerical solutions.

    Complements

    Complements를 정의합니다. 예를 들어, 솔리드 구의 complements는 솔리드 재료로 둘러싸인 구형 구멍입니다.

    The inverse of a shape defines the complement. For example, the complement of a solid sphere is a spherical hole surrounded by solid material.

    Client

    클라이언트 컴퓨터는 자신이 FLOW-3D를 실행하고 있지만, FLOW-3D 소프트웨어 라이선스는 다른 컴퓨터 (서버 컴퓨터)에서 획득하는 컴퓨터를 의미합니다.

    A client machine is a computer that runs FLOW-3D  but acquires the software license from a different machine (the server machine)

    Components

    Components는 공간의 개체를 정의하며 하위 구성 요소로 구성됩니다. 구성 요소는 열 전도율, 비열 및 표면 거칠기와 같은 재료 특성을 가질 수 있습니다.

    Components define objects in space and are comprised of subcomponents. A component can have material properties such as thermal conductivity, specific heat and surface roughness.

    Custom result

    시뮬레이션 중 또는 완료 후 사용자가 생성한 데이터를 그래픽으로 표시합니다. 생성하려면 사용자가 flsgrf결과 파일을 연 다음 플로팅 매개 변수(예 : 플로팅 할 도메인 부분, 플로팅 할 수량 등)를 선택해야 합니다.

    Graphical displays of data generated by the user during the simulation or after it has completed. To generate, the user must open an flsgrf results file and then select the plotting parameter (e.g., portion of domain to plot, quantity to plot, etc.).

    Domain

    지배 방정식을 풀 영역입니다. 이것은 메쉬의 범위에 의해 정의됩니다.

    The region in which the governing equations are to be solved. This is defined by the extents of the mesh.

    Diagnostics

    전 처리기 및 솔버의 진행 상황과 오류 및 경고에 대한 정보가 포함된 파일 세트입니다.

    A suite of files that contain information on the progress of the preprocessor and solver as well as errors and warnings.

    EPSI

    압력/연속 반복이 어느 지점에서 수렴되는지를 결정하는데 사용된 수렴 기준입니다. 기본 숫자 설정을 사용하면 이 값은 FLOW-3D에 의해 자동으로 계산되며 시간 단계가 증가함에 따라 작아집니다.

    The convergence criterion that was used to determine at what point the pressure/continuity iterations have converged. With the default numerical settings, this value is automatically computed by FLOW-3D  and becomes smaller as the time step increases.

    Existing result

    prpplt.* 또는 flsplt.* 파일은 전처리 종료 솔버 실행 종료시 또는 자동으로 생성되는 플롯 파일입니다.

    A plot file that is automatically created, either at the end of preprocessing or the end of the solver run- prpplt.* or flsplt.*.

    F3D_HOME

    FLOW-3D 프로그램 파일이 있는 디렉토리를 정의하는 환경 변수.

    Environment variable that defines the directory where the FLOW-3D  program files are located.

    Floating license

    FLOW-3D는 서버 시스템에 라이센스를 액세스하는 각 클라이언트 컴퓨터와 컴퓨터 네트워크에서 실행합니다. 허용하는 라이센스 최대 동시 시뮬레이션 수는 구매한 솔버 토큰 수에 의해 제한됩니다.

    A license that allows FLOW-3D  to be run on a network of computers with each client machine accessing the license on a server machine. The maximum number of concurrent simulations is limited by the number of solver tokens purchased.

    Flsgrf file

    솔버가 생성한 결과 파일. 이 파일은 사전에 정의된 시간 간격으로 생성된 정보를 포함하며 그래픽 디스플레이를 생성하는 데 사용됩니다. 사용자 정의 플로팅 중에 포스트 프로세서에서 사용합니다.

    Results file produced by the solver. This file contains information produced at predefined time intervals and is used to produce graphical displays. Used by the postprocessor during custom plotting.

    Flsplt file

    솔버가 자동으로 생성한 플롯 파일입니다. 이 파일에는 시뮬레이션의 히스토리 데이터, 메시 등에 대한 기본 정보와의 $GRAFIC 이름 목록에 사전 정의된 그래픽 요청이 포함되어 prepin.* 파일 안에 있습니다.

    Plot file produced automatically by the solver. This file contains basic information on history data, mesh, etc. from the simulation as well as any pre-defined graphics requests in the $GRAFIC namelist in prepin.*.

    Fluid #1 surface area

    선택한 길이 단위의 자유 표면 영역을 제곱 됩니다. 인터페이스가 예리한 문제에만 해당됩니다.

    The free-surface area in the chosen length units squared. This is only relevant for problems with a sharp interface.

    Fluid thermal energy

    영역에 존재하는 모든 유체에 포함된 총 열 에너지 (에너지 전송이 켜져 있는 시뮬레이션에만 해당).

    The total thermal energy contained by all the fluid present in the domain (relevant only for simulations with energy transport turned on).

    Free surface

    유체와 유체 사이의 인터페이스. FLOW-3D에서 이 인터페이스는 전단이 없는 것으로 가정되며, 이는 빈 공간에 있는 가스가 유체에 무시할 수 있는 트랙션을 발휘함을 의미한다.

    The interface between fluid and void. In FLOW-3D , this interface is assumed to be shear-free, meaning that any gas in the void space exerted negligible traction on the fluid.

    GUI

    ” Graphical User Interface”.  GUI는 사용자가 FLOW-3D를 제어할 수 있는 그래픽 패널, 대화 상자 및 창을 제공합니다.

    “Graphical User Interface”. The GUI presents the graphical panels, dialog boxes and windows that allow the user to control FLOW-3D .

    Iteration count

    각 시간 단계에서 필요한 압력/연속 반복 횟수입니다. 압력/연속성 반복은 유체 볼륨이 유지되도록 하고 유체 전체에서 올바른 압력을 계산하는 데 필요합니다.

    The number of pressure/continuity iterations required at each time step. The pressure/continuity iterations are necessary to ensure that the fluid volume is maintained and to compute the correct pressure throughout the fluid.

    License file

    사용자가 FLOW-3D 를 실행할 수 있도록 암호화된 정보가 포함된 Flow Science에서 제공하는 전자 파일 입니다.

    Electronic file provided by Flow Science that contains encrypted information enabling the user to run FLOW-3D .

    License server

    플로팅 라이센스 시스템의 작동을 활성화하기 위해 FLEXlm 라이센스 소프트웨어가 설치된 시스템. FLOW-3D는 License Server에 설치할 필요가 없습니다.

    Computer on which the FLEXlm licensing software is installed to enable the operation of a floating license system. FLOW-3D  does not need to be installed on the license server.

    Licensing

    FLOW-3D 실행을 제어하는 ​​FLEXlm 소프트웨어.

    FLEXlm software that controls the running of FLOW-3D .

    Max. residual

    압력/연속성 반복의 최종 반복에서 연속성 방정식의 실제 발산. 이 값은 메시지가 나타나지 않는 한 일반적으로 epsi보다 작습니다 .

    The actual divergence of the continuity equation on the final iteration of the pressure/continuity iterations. This value is usually smaller than epsi unless the message, pressure iteration did not converge in xxxx iterations appears.

    Mean kinetic energy

    모든 계산 셀의 운동 에너지의 합을 도메인에 존재하는 총 유체 질량으로 나눈 값입니다. 이 양이 시간이 지남에 따라 변하지 않으면 정상 상태에 도달했음을 나타내는 좋은 지표입니다.

    The sum of kinetic energy of all the computational cells, divided by the total mass of fluid present in the domain. When this quantity ceases to change over time, it is a good indicator that steady-state has been reached.

    Node-locked license

    특정 컴퓨터에 고정된 라이센스. 노드 잠금 라이센스는 네트워크를 통해 액세스 할 수 없으므로 일반적으로 모든 작업을 한 컴퓨터에서 수행해야하는 경우에만 사용됩니다.

    A license that is locked to a particular computer. A node-locked license cannot be accessed across a network, and so is typically only used when all work is to be done on one computer.

    Non-inertial reference frame

    가속화되는 참조 프레임. 비 관성 참조 프레임은 움직이는 컨테이너를 모방하는 데 사용할 수 있습니다.

    A frame of reference that is accelerating. A non-inertial reference frame can be used to mimic a moving container.

    Pltfsi

    1D 및 2D 플롯을 생성하는 FLOW-3D에 포함된 그래픽 디스플레이 프로그램.

    Graphics display program included with FLOW-3D  that produces 1D and 2D plots.

    Postprocessor

    FLOW-3D 내의 Postprocessor 프로그램은 FLOW-3D 또는 타사 시각화 프로그램에서 읽을 수 있는 데이터 파일을 생성하거나 타사 소프트웨어 프로그램에서 읽을 텍스트 데이터를 생성하는 솔버 출력 데이터를 처리하는 프로그램입니다.

    The program within FLOW-3D  that processes the solver output data to produce data files that can be read by FLOW-3D ’s or third-party’s visualization programs, or produce text data to be read by third party software programs.

    Prepin file

    FLOW-3D 시뮬레이션을 실행하는데 필요한 모든 정보가 포함된 텍스트 파일 입니다. GUI를 사용하거나 텍스트 편집기를 사용하여 수동으로 작성할 수 있습니다.

    Text file that contains all of the information necessary to create a FLOW-3D  simulation. It can be created using the GUI or manually with a text editor.

    Preprocessor

    솔버의 실행을 준비하기 위해 입력 파일을 기반으로 메쉬 및 초기 조건을 생성하는 FLOW-3D 내의 프로그램 입니다.

    The program within FLOW-3D  that generates the mesh and initial conditions based on the input file in preparation for the running of the solver.

    Prpgrf file

    전처리기에 의해 생성된 결과 파일로 전 처리기의 정보를 포함하며 후 처리기에서 사용자 플롯을 생성하는 데 사용할 수 있습니다. 이 파일은 미리보기 버튼을 선택하거나 시뮬레이션에서 사전 프로세서(runpre 사용)를 실행하는 경우에만 실행됩니다.

    Results file produced by the preprocessor. Contains information from the preprocessor and can be used by the postprocessor to create custom plots. This file is produced only when the Preview button is selected or if only the pre-processor is run on the simulation (using runpre).

    Prpplt file

    전처리기에 의해 자동으로 생성된 파일을 플롯 합니다. 메시, 구성 요소, 초기 조건 및 재료 특성에 대한 정보가 포함되어 있습니다.

    Plot file produced automatically by the preprocessor. Contains information on meshing, components, initial conditions and material properties.

    Restart simulation

    이전 시뮬레이션에서 계속되는 시뮬레이션입니다. 이전 시뮬레이션의 결과는 다시 시작 시뮬레이션을 위한 초기 조건 및 (선택적으로) 경계 조건을 생성하는 데 사용됩니다.

    A simulation which continues from a previous simulation. The results from the previous simulation are used to generate the initial conditions and (optionally) boundary conditions for the restart simulation.

    Server

    라이센스 서버를 호스팅하는 시스템

    The machine that hosts the license server.

    Stability limit

    각 시간 단계에서 사용할 수 있는 최대 시간 단계. 더 큰 시간 단계는 수치적 불안정성과 비물리적 결과로 이어질 것이다.

    The maximum time step that can be used during each time step. A larger time step will lead to numerical instabilities and nonphysical results.

    STL (Stereolithography) File

    .STL 파일 형식은 일련의 삼각형이 있는 솔리드 모델의 표면에 근접한 표준 데이터 전송 형식이다. 삼각형은 가장자리에서 결합해야 하며 일관된 방향을 가리키는 정규식이 있어야 한다.

    The .STL file format is a standard data transmission format that approximates the surfaces of a solid model with a series of triangles. The triangles must join at the edges and must have normals that point in a consistent direction.

    Solid fraction

    응고된 영역의 유체 분율 (응고 모델이 켜져 있는 시뮬레이션에만 해당).

    The fraction of fluid in the domain that has become solidified (relevant only for simulations where the solidification model has been turned on).

    Solver

    입력 파일에 정의된 흐름 문제를 시뮬레이션하는 방정식을 계산하는 FLOW-3D 내의 솔버 프로그램 입니다.

    The program within FLOW-3D  that solves the system of equations that simulate the flow problem defined in the input file.

    STL Viewer

    스테레오리소그래피(STL) 파일을 표시하는 특수 유틸리티입니다. STL 파일은 CAD 소프트웨어로 제작되며 3 차원 객체의 표면을 형성하는 많은 삼각형으로 구성됩니다. 의 STL 뷰어 FLOW-3D는 메인 메뉴에서 유틸리티/STL 뷰어를 클릭하여 GUI를 통해 액세스 할 수 있습니다. 그러면 뷰어가 별도의 창에서 열립니다. 메쉬 및 형상 탭에서 STL 파일을 열고 볼 수도 있습니다.

    A special utility that displays stereolithography (STL) files. STL files are produced by CAD software and are composed of many triangles that form the surface of a three-dimensional object. The STL Viewer in FLOW-3D  is accessible via the GUI by clicking Utilities/STL Viewer in the main menu. This causes the viewer to open in a separate window. STL files can also be opened and viewed in the Meshing and Geometry tab.

    Subcomponents

    하위 구성 요소는 구성 요소라고하는 더 큰 모양을 형성하기 위해 결합할 수 있는 기하학적 모양입니다. 하위 구성 요소는 재료를 추가하거나 (고체로) 다른 하위 구성 요소에서 재료를 제거하거나 (구멍으로) 또는 모양 외부에 재료를 추가하도록 정의할 수 있습니다.

    Subcomponents are geometric shapes that can be combined to form larger shapes, called components. A subcomponent can be defined to add material (as solids), remove material from other subcomponents (as holes), or add material outside of the shape (as a complement).

    Time-step size

    계산에 사용된 실제 시간 단계. 이 값은 안정성 한계와 같거나 작을 수 있습니다.

    The actual time step used in the computation. This value can be equal to or less than the stability limit.

    Units

    Units are based upon the values set for the physical properties. Items such as mesh block extents and cell lengths automatically conform to the units used for setting these physical properties.

    단위는 물리적 특성에 설정된 값을 기반으로 합니다. 메쉬 블록 범위 및 셀 길이와 같은 항목은 이러한 물리적 속성을 설정하는 데 사용되는 단위를 자동으로 따릅니다.

    Volume error (%)

    주어진 시간에 도메인에 존재하는 총 유체의 백분율로 설명되지 않은 유체 부피의 백분율을 의미합니다. 따라서 단순히 총 부피가 작기 때문에 유체가 시스템 밖으로 배출되는 시뮬레이션에서 큰 비율의 부피 오류가 발생할 수 있습니다.

    The percentage of fluid volume not accounted for as a percentage of the total fluid present in the domain at a given time. Therefore, a large percentage volume error can occur for simulations where fluid is draining out of the system simply because the total volume present is small.

    Volume of fluid #1

    선택한 길이 단위로 입방체에 존재하는 유체 #1의 총 부피입니다. 2 유체 문제의 경우, 유체 #2의 부피는 항상 도메인 부피에서 유체 #1의 부피를 뺀 값입니다.

    The total volume of fluid #1 present in the system, in the chosen length units cubed. For two-fluid problems, the volume of fluid #2 is always the domain volume minus the volume of fluid #1.

    Wall shear stress

    FLOW-3D 옵션은 벽면 및 객체 인터페이스에서 전단 응력 계산을 켜거나 끌 수 있도록 해줍니다. “no-slip” 인터페이스의 효과를 모델링 하려면 벽면 전단 응력을 켜야 합니다.

    The FLOW-3D  option that allows the user to turn on or off the computation of shear stress at wall and object interfaces. Wall shear stress must be turned on to model the effect of “no-slip” interfaces.

    Workspace

    작업 공간은 시뮬레이션 프로젝트를 위한 파일 컨테이너입니다. 작업 공간은 사용자가 FLOW-3D 뿐만 아니라 하드 드라이브에서도 작업을 구성하는 데 도움이 됩니다.

    A workspace is a file container for simulation projects. Workspaces help the user organize their work, not only within FLOW-3D , but also on their hard drive.

    FLOW-3D 및TruVOF는 미국 및 기타 국가에서 등록 상표입니다.

    FLOW-3D 기술자료로 이동

    Figure 9: Predicted three-dimensional spreading splats for a 90 µm diameter Nylon-11 droplet.

    Effect of Substrate Roughness on Splatting Behavior of HVOF Sprayed Polymer Particles: Modeling and Experiments

    International Thermal Spray Conference – ITSC-2006
    Seattle, Washington, U.S.A., May 2006

    M. Ivosevic, V. Gupta, R. A. Cairncross, T. E. Twardowski, R. Knight,
    Drexel University, Philadelphia, Pennsylvania, USA
    J. A. Baldoni
    Duke University, North Carolina, USA

    Abstract

    거친 표면에 대한 입자 충격 및 변형의 3 차원 모델이 HVOF 스프레이 폴리머 입자에 대해 개발되었습니다. 유체 흐름 및 입자 변형은 FLOW-3D® 소프트웨어를 사용하는 유체 부피 (VoF) 방법으로 예측되었습니다. 스플래팅(splatting) 및 최종 스플랫 모양(splat shapes)의 역학에 대한 거칠기의 영향은 몇 가지 프로토타입 거친 표면을 사용하여 탐색 되었습니다 (예: 단계와 그루브)

    또한 실제 그릿 블라스팅(grit blasted)된 강철 표면의 광학 간섭 측정에 의해 생성된 보다 사실적인 거친 표면의 수치 표현도 모델에 통합되었습니다. 예측된 스플랫 모양을 그릿 블라스팅 된 강철 기판에 증착된 나일론 11 스플랫의 SEM 이미지와 비교했습니다. 거친 기판은 부드러운 기판의 스플래팅 시뮬레이션에서 거의 관찰되지 않는 손가락 및 기타 비대칭 3 차원 불안정성을 생성했습니다.

    Introduction

    기판 거칠기가 용사 코팅의 접착력과 접착력을 향상 시킨다는 사실은 잘 알려져 있으며 일반적으로 받아 들여지고 있습니다 [1]. 스프레이하기 전에 기판 표면은 일반적으로 알루미나 또는 SiC와 같은 50 – 300 µm 각 세라믹 입자로 그릿 블라스팅으로 거칠게 처리됩니다.

    기판 표면에 증착된 초기 스플랫의 형태는 코팅 / 기판 인터페이스의 무결성과 결과 코팅의 접착 강도에 중요한 역할을합니다. 단단하고 불규칙한 표면에 대한 열 스프레이 액적의 충격 및 변형은 액적 표면의 복잡한 대규모 3 차원 변형이 특징입니다.

    충돌하는 물방울의 “스플래싱”이 발생하는 경우, 운지법 또는 위성 입자 생성 및 분리 중 새로운 표면 생성은 일반적으로 축 대칭이 아니므로 사실적인 splat 예측을 위해 3 차원 모델이 필요합니다. 이것은 정확한 3 차원 스플래팅 모델의 개발에 많은 수치적 도전을 야기합니다.

    Fauchais et al. [2]는 스플랫 형성 과정과 관련하여 발표 된 논문의 대부분 (~ 98 %)이 매끄러운 표면에 대한 정상적인 액적 충격을 설명한다고보고했습니다. 게시된 작업의 2 % 미만은 매끄러운 표면에 대한 비정상적인 입자 영향과 관련이 있으며 ~ 0.1 %만이 거친 기판과 관련됩니다.

    여러 저자 [3, 4]는 2 차원 모델을 사용하여 비평면 표면과 물방울의 상호 작용을 연구했거나 평행 그루브가 있는 표면에 대한 3 차원 충격 [5]을 연구했습니다. 그러나 이 접근법의 주요 단점은 거친 표면에 스플래팅의 비축 대칭 측면을 연구합니다.

    최근 Raessi et al. [6] 이전에 개발된 VoF 모델 [7]을 확장하여 평평한 기판에 액적 스플래팅을 프로토 타입 거친 표면과 액적 상호 작용으로 확장했습니다. 표면 거칠기는 규칙적으로 정렬 된 정사각형 블록으로 근사화 되었습니다. Feng et al. [8]은 평평한 표면의 마찰 조건에 의해 표면 거칠기가 근사된 3 차원 Lagrangian 유한 요소 모델을 사용했습니다.

    이 접근 방식은 소규모 점성 및 축 대칭 자유 표면 흐름과 관련하여 매우 정확할 수 있지만 fingering 생성 또는 satellites 생성 및 breakups 중 새로운 표면 생성과 관련된 물방울이 튀기는 경계 맞춤 기술에 적합하지 않습니다.

    또한, 열 분무에 사용되는 그릿 블라스팅 표면의 평균 표면 거칠기 (Ra)는 일반적으로 50μm의 평균 액적 크기에 비해 ~ 5 ~ 30 % (~ 2 ~ 15μm)입니다. 평평한 표면에 간단한 마찰 흐름.

    본 연구의 목표는 임의의 거친 기질에 영향을 미치는 HVOF 분무 중합체 입자의 모델을 개발하는 것이다. 매끄럽지 않은 표면에 대한 입자 분할 모델은 표면의 기하학적 불규칙성이 분할 거동과 최종 분할 형태에 어떻게 영향을 미치는지 더 잘 이해할 수 있게 해줄 것입니다.

    HVOF 제트에서 미크론 크기의 공급 원료 입자로의 강제 대류는 높은 대류 열 전달 계수 (h ~ 5000 – 17,000 W / (m2 K))를 특징으로 합니다. 이로 인해 입자 표면 온도가 급격히 증가하지만 폴리머 입자의 높은 내부 열 저항 (높은 Bi 수)은 입자 내부가 동일한 속도로 가열되는 것을 방지합니다. 결과적으로 더 큰 (예 : 90 µm 직경) 나일론 11 입자는 기판에 충격을 주기 전에 코어와 표면 사이에 급격한 온도 구배를 나타냅니다 (그림 1) [9, 10, 11].

    Figure 1: Temperature of a 90 µm diameter Nylon 11 particle with respect to normalized particle radius (r/R) [10].
    Figure 1: Temperature of a 90 µm diameter Nylon 11 particle with respect to normalized particle radius (r/R) [10].
    Figure 2: (a) Velocity field within a spreading 90 µm diameter particle; (Left): velocity magnitude, (Right): velocity vectors, (b) example Nylon 11 splat deposited via swipe test onto a room temperature glass slide.
    Figure 2: (a) Velocity field within a spreading 90 µm diameter particle; (Left): velocity magnitude, (Right): velocity vectors, (b) example Nylon 11 splat deposited via swipe test onto a room temperature glass slide.

    또한 가파른 내부 온도 구배를 가진 HVOF 스프레이 폴리머 입자가 얇은 디스크 중앙에 크고 거의 반구형 인 코어가있는 특징적인 “튀김 달걀”모양으로 퍼졌다고 보고되었습니다 [10]. 이 모양은 저온, 고점도 코어와 고온, 저점도 표면의 유동 특성 간에 큰 방사형 차이가 있음을 나타냅니다.

    변형된 입자의 예측 된 모양 (그림 2a)은 유리 슬라이드에 증착된 실험적으로 관찰 된 스플랫과 좋은 질적 일치를 나타 냈습니다 (그림 2b). 액적의 오른쪽에 표시된 속도 장 벡터 (그림 2a)는 저점도 “피부”가 고점도 코어 주위를 흐르면서 특징적인 “튀김 달걀” splat 모양이 형성되었음을 나타냅니다.

    이 작업에서 보고된 실험 중에 사용된 HVOF 스프레이 매개 변수는 나일론 11을 증착하는데 사용할 수 있는 일반적인 HVOF 스프레이 매개 변수를 나타냅니다. 그러나 실험 기준 매개 변수를 중심으로 개발된 수치 모델은 개별 스플랫의 흐름 거동을 더 잘 이해하는 데 사용할 수 있습니다. 증착 효율 향상을 위한 공정 최적화를 지원합니다.

    Figure 3: Boundary conditions, initial conditions and crosssection of a typical mesh used in Flow-3D
    Figure 3: Boundary conditions, initial conditions and crosssection of a typical mesh used in Flow-3D
    Figure 5: Cross section of four steel substrates: (a) polished with ~1 Pm alumina suspension, (b) grit blasted with #120 grit, (c) grit blasted with #50 grit, (d) grit blasted with #12 grit. Top image shows optical interferometry scan of # 120 grit blasted surface.
    Figure 5: Cross section of four steel substrates: (a) polished with ~1 Pm alumina suspension, (b) grit blasted with #120 grit, (c) grit blasted with #50 grit, (d) grit blasted with #12 grit. Top image shows optical interferometry scan of # 120 grit blasted surface.
    Figure 6: Nylon-11 splats deposited during a single run over steel substrates with roughnesses as per Figure 5.
    Figure 6: Nylon-11 splats deposited during a single run over steel substrates with roughnesses as per Figure 5.
    Figure 7: Nylon-11 splat on a grit blasted steel substrate, (a) close up of a peripheral splat finger.
    Figure 7: Nylon-11 splat on a grit blasted steel substrate, (a) close up of a peripheral splat finger.
    Figure 8: Cross-sections of predicted three-dimensional spreading splats for a 90 µm diameter Nylon-11 particle on four different surface roughnesses (dimensionless time t* = t/(D/v o (p))).
    Figure 8: Cross-sections of predicted three-dimensional spreading splats for a 90 µm diameter Nylon-11 particle on four different surface roughnesses (dimensionless time t* = t/(D/v o (p))).
    Figure 9: Predicted three-dimensional spreading splats for a 90 µm diameter Nylon-11 droplet.
    Figure 9: Predicted three-dimensional spreading splats for a 90 µm diameter Nylon-11 droplet.

    중략…….

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    Figure 1.1: A water droplet with a radius of 1 mm resting on a glass substrate. The surface of the droplet takes on a spherical cap shape. The contact angle θ is defined by the balance of the interfacial forces.

    Effect of substrate cooling and droplet shape and composition on the droplet evaporation and the deposition of particles

    기판 냉각 및 액적 모양 및 조성이 액적 증발 및 입자 증착에 미치는 영향

    by Vahid Bazargan
    M.A.Sc., Mechanical Engineering, The University of British Columbia, 2008
    B.Sc., Mechanical Engineering, Sharif University of Technology, 2006
    B.Sc., Chemical & Petroleum Engineering, Sharif University of Technology, 2006

    고착 방울은 평평한 기판에 놓인 액체 방울입니다. 작은 고정 액적이 증발하는 동안 액적의 접촉선은 고정된 접촉 영역이 있는 고정된 단계와 고정된 접촉각이 있는 고정 해제된 단계의 두 가지 단계를 거칩니다. 고정된 접촉 라인이 있는 증발은 액적 내부에서 접촉 라인을 향한 흐름을 생성합니다.

    이 흐름은 입자를 운반하고 접촉 선 근처에 침전시킵니다. 이로 인해 일반적으로 관찰되는 “커피 링”현상이 발생합니다. 이 논문은 증발 과정과 고착성 액적의 증발 유도 흐름에 대한 연구를 제공하고 콜로이드 현탁액에서 입자의 침착에 대한 통찰력을 제공합니다. 여기서 우리는 먼저 작은 고착 방울의 증발을 연구하고 증발 과정에서 기판의 열전도도의 중요성에 대해 논의합니다.

    현재 증발 모델이 500µm 미만의 액적 크기에 대해 심각한 오류를 생성하는 방법을 보여줍니다. 우리의 모델에는 열 효과가 포함되어 있으며, 특히 증발 잠열의 균형을 맞추기 위해 액적에 열을 제공하는 기판의 열전도도를 포함합니다. 실험 결과를 바탕으로 접촉각의 진화와 관련된 접촉 선의 가상 움직임을 정의하여 고정 및 고정 해제 단계의 전체 증발 시간을 고려합니다.

    우리의 모델은 2 % 미만의 오차로 500 µm보다 작은 물방울에 대한 실험 결과와 일치합니다. 또한 유한한 크기의 라인 액적의 증발을 연구하고 증발 중 접촉 라인의 복잡한 동작에 대해 논의합니다. 에너지 공식을 적용하고 접촉 선이 구형 방울의 후퇴 접촉각보다 높은 접촉각을 가진 선 방울의 두 끝에서 후퇴하기 시작 함을 보여줍니다. 그리고 라인 방울 내부의 증발 유도 흐름을 보여줍니다.

    마지막으로, 계면 활성제 존재 하에서 접촉 라인의 거동을 논의하고 입자 증착에 대한 Marangoni 흐름 효과에 대해 논의합니다. 열 Marangoni 효과는 접촉 선 근처에 증착 된 입자의 양에 영향을 미치며, 기판 온도가 낮을수록 접촉 선 근처에 증착되는 입자의 양이 많다는 것을 알 수 있습니다.

    Figure 1.1: A water droplet with a radius of 1 mm resting on a glass substrate. The surface of the droplet takes on a spherical cap shape. The contact angle θ is defined by the balance of the interfacial forces.
    Figure 1.1: A water droplet with a radius of 1 mm resting on a glass substrate. The surface of the droplet takes on a spherical cap shape. The contact angle θ is defined by the balance of the interfacial forces.
    Figure 2.1: Evaporation modes of sessile droplets on a substrate: (a) evaporation at constant contact angle (de-pinned stage) and (b) evaporation at constant contact area (pinned stage)
    Figure 2.1: Evaporation modes of sessile droplets on a substrate: (a) evaporation at constant contact angle (de-pinned stage) and (b) evaporation at constant contact area (pinned stage)
    Figure 2.2: A sessil droplet with its image can be profiled as the equiconvex lens formed by two intersecting spheres with radius of a.
    Figure 2.2: A sessil droplet with its image can be profiled as the equiconvex lens formed by two intersecting spheres with radius of a.
    Figure 2.3: The droplet life time for both evaporation modes derived from Equation 2.2.
    Figure 2.3: The droplet life time for both evaporation modes derived from Equation 2.2.
    Figure 2.4: A probability of escape for vapor molecules at two different sites of the surface of the droplet for diffusion controlled evaporation. The random walk path initiated from a vapor molecule is more likely to result in a return to the surface if the starting point is further away from the edge of the droplet.
    Figure 2.4: A probability of escape for vapor molecules at two different sites of the surface of the droplet for diffusion controlled evaporation. The random walk path initiated from a vapor molecule is more likely to result in a return to the surface if the starting point is further away from the edge of the droplet.
    Figure 2.5: Schematic of the sessile droplet on a substrate
    Figure 2.5: Schematic of the sessile droplet on a substrate. The evaporation rate at the surface of the droplet is enhanced toward the edge of the droplet.
    Figure 2.6: The domain mesh (a) and the solution of the Laplace equation for diffusion of the water vapor molecule with the concentration of Cv = 1.9×10−8 g/mm3 at the surface of the droplet into the ambient air with the relative humidity of 55%, i.e. φ = 0.55 (b).
    Figure 2.6: The domain mesh (a) and the solution of the Laplace equation for diffusion of the water vapor molecule with the concentration of Cv = 1.9×10−8 g/mm3 at the surface of the droplet into the ambient air with the relative humidity of 55%, i.e. φ = 0.55 (b).
    Figure 3.1: The portable micro printing setup. A motorized linear stage from Zaber Technologies Inc. was used to control the place and speed of the micro nozzle.
    Figure 3.1: The portable micro printing setup. A motorized linear stage from Zaber Technologies Inc. was used to control the place and speed of the micro nozzle.
    Figure 4.6: Temperature contours inside the substrate adjacent to the droplet
    Figure 4.6: Temperature contours inside the substrate adjacent to the droplet
    Figure 4.7: The effect of substrate cooling on the evaporation rate, the basic model shows the same value for all substrates.
    Figure 4.7: The effect of substrate cooling on the evaporation rate, the basic model shows the same value for all substrates.

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    [54] X. Fang, B. Li, J. C. Sokolov, M. H. Rafailovich, and D. Gewaily, “Hildebrand solubility parameters measurement via sessile drops evaporation,” Applied Physics Letters, vol. 87, pp. 094103–094103–3, Aug.→ pages
    [55] Y. C. Jung and B. Bhushan, “Wetting behaviour during evaporation and condensation of water microdroplets on superhydrophobic patterned surfaces,” Journal of Microscopy, vol. 229, no. 1, p. 127140, 2008. → pages 71
    [56] J. Drelich, J. D. Miller, and R. J. Good, “The effect of drop (bubble) size on advancing and receding contact angles for heterogeneous and rough solid surfaces as observed with sessile-drop and captive-bubble techniques,”
    Journal of Colloid and Interface Science, vol. 179, pp. 37–50, Apr. 1996. →pages 72, 75
    [57] D. Bargeman and F. Van Voorst Vader, “Effect of surfactants on contact angles at nonpolar solids,” Journal of Colloid and Interface Science, vol. 42, pp. 467–472, Mar. 1973. → pages 73
    [58] J. Menezes, J. Yan, and M. Sharma, “The mechanism of alteration of macroscopic contact angles by the adsorption of surfactants,” Colloids and Surfaces, vol. 38, no. 2, pp. 365–390, 1989. → pages
    [59] T. Okubo, “Surface tension of structured colloidal suspensions of polystyrene and silica spheres at the air-water interface,” Journal of Colloid and Interface Science, vol. 171, pp. 55–62, Apr. 1995. → pages 73, 76
    [60] R. Pyter, G. Zografi, and P. Mukerjee, “Wetting of solids by surface-active agents: The effects of unequal adsorption to vapor-liquid and solid-liquid interfaces,” Journal of Colloid and Interface Science, vol. 89, pp. 144–153, Sept. 1982. → pages 73
    [61] T. Mitsui, S. Nakamura, F. Harusawa, and Y. Machida, “Changes in the interfacial tension with temperature and their effects on the particle size and stability of emulsions,” Kolloid-Zeitschrift und Zeitschrift fr Polymere, vol. 250, pp. 227–230, Mar. 1972. → pages 73
    [62] S. Phongikaroon, R. Hoffmaster, K. P. Judd, G. B. Smith, and R. A. Handler, “Effect of temperature on the surface tension of soluble and insoluble surfactants of hydrodynamical importance,” Journal of Chemical & Engineering Data, vol. 50, pp. 1602–1607, Sept. 2005. → pages 73, 80
    [63] V. S. Vesselovsky and V. N. Pertzov, “Adhesion of air bubbles to the solid surface,” Zh. Fiz. Khim, vol. 8, pp. 245–259, 1936. → pages 75
    [64] Hideo Nakae, Ryuichi Inui, Yosuke Hirata, and Hiroyuki Saito, “Effects of surface roughness on wettability,” Acta Materialia, vol. 46, pp. 2313–2318, Apr. 1998. → pages
    [65] R. J. Good and M. Koo, “The effect of drop size on contact angle,” Journal of Colloid and Interface Science, vol. 71, pp. 283–292, Sept. 1979. → pages

    FLOW-3D What’s New Ver.12.0

    FLOW-3D v12는 그래픽 사용자 인터페이스 (GUI)의 설계 및 기능에서 매우 큰 변화를 이룬 제품으로 모델 설정을 단순화하고 사용자 워크 플로를 향상시킵니다. 최첨단 Immersed Boundary Method(침수경계 방법)은 FLOW-3D v12 솔루션의 정확성을 높여줍니다. 다른 주요 기능으로는 슬러지 침강 모델, 2-Fluid 2-Temperature 모델 및 Steady State Accelerator가 있으며,이를 통해 사용자는 자유 표면 흐름을 더욱 빠르게 모델링 할 수 있습니다.

    Physical and Numerical Model

    Immersed boundary method

    힘과 에너지 손실에 대한 정확한 예측은 고체 주위의 흐름과 관련된 많은 엔지니어링 문제를 모델링하는 데 중요합니다. 새 릴리스 FLOW-3D v12에는 이러한 문제점 해결을 위해 설계된 새로운 고스트 셀 기반 Immersed Boundary Method (IBM)가 있습니다. IBM은 내 외부 흐름 해석을 위해, 벽 근처에서 보다 정확한 해를 제공하여 드래그 앤 리프트 힘의 계산을 향상시킵니다.힘과 에너지 손실의 정확한 예측은 고체 주위의 흐름을 포함하는 많은 공학적 문제를 모델링 하는데 중요합니다.

    Two-field temperature for the two-fluid model

    2 유체 열전달 모델은 각 유체에 대한 에너지 전달 방정식을 분리하기 위해 확장되었습니다. 각 유체는 이제 자체 온도 변수를 가지므로 인터페이스 근처의 열 및 물질 전달 솔루션의 정확도가 향상됩니다. 인터페이스에서의 열전달은 이제 시간의 표 함수가 될 수 있는 사용자 정의 열전달 계수에 의해 제어됩니다.

    블로그 보기

    Sludge settling model

    새로운 슬러지 정착 모델은 수처리 애플리케이션에 부가되어 사용자들이 수 처리 탱크와 클래리퍼의 고형 폐기물 역학을 모델링 할 수 있게 해 줍니다. 침전 속도가 분산상의 액적 크기의 함수 인 드리프트-플럭스 모델과 달리, 침전 속도는 슬러지 농도의 함수이며 기능 및 표 형식으로 입력 할 수 있습니다.

    개발노트 읽기

    Steady-state accelerator for free surface flows

    이름에서 알 수 있듯이 정상 상태 가속기는 정상 상태 솔루션에 대한 접근을 빠르게합니다.
    이것은 작은 진폭 중력과 모세관 표면파를 감쇠시킴으로써 달성되며 자유 표면 흐름에만 적용 할 수 있습니다.

    개발노트 읽기

    Void particles

    Void particles 가 기포 및 상 변화 모델에 추가되었습니다. Void particles는 붕괴 된 Void 영역을 나타내며, 항력 및 압력을 통해 유체와 상호 작용하는 작은 기포로 작용합니다. 주변 유체 압력에 따라 크기가 변하고 시뮬레이션이 끝날 때의 최종 위치는 공기 유입 가능성을 나타냅니다.

    Sediment scour model

    퇴적물 수송 및 침식 모델은 정확성과 안정성을 향상시키기 위해 정비되었습니다. 특히 퇴적물 종의 질량 보존이 크게 개선되었습니다.

    개발 노트 읽기>

    Outflow pressure boundary condition

    고정 압력 경계 조건에는 압력 및 유체 분율을 제외한 모든 유량이 해당 경계의 상류의 유량 조건을 반영하는 ‘유출’옵션이 포함됩니다. 유출 압력 경계 조건은 고정 압력 및 연속 경계 조건의 하이브리드입니다.

    Moving particle sources

    시뮬레이션 중에 입자 소스를 이동할 수 있습니다. 시간에 따른 병진 및 회전 속도는 표 형식으로 정의됩니다. 입자 소스의 운동은 소스에서 방출 된 입자의 초기 속도에 추가됩니다.

    Variable center of gravity

    기변 무게중심은 중력 및 비관 성 기준 프레임 모델에서, 시간의 함수로서 무게 중심의 위치는 외부 파일에서 테이블로서 정의 될 수있다. 이 기능은 연료를 소비하고 분리 단계를 수행하는 로켓과 같은 모형을 모델링 할 때 유용합니다.

    공기 유입 모델

    가장 간단한 부피 기반 공기 유입 모델 옵션이 기존 질량 기반 모델로 대체되었습니다. 질량 기반 모델은 부피와 달리 주변 유체 압력에 따라 부피가 변화하는 동안 흡입된 공기량이 보존되기 때문에 물리학적 모델입니다.

    Tracer diffusion

    유동 표면에서 생성된 추적 물질은 분자 및 난류 확산 과정에 의해 확산될 수 있으며, 예를 들어 실제 오염 물질의 동작을 모방한다.

    Model Setup

    Simulation units

    온도를 포함하여 단위 시스템은 완전히 정의해야하는데 표준 단위 시스템이 제공됩니다. 또한 사용자는 다양한 옵션 중에서 질량, 시간 및 길이 단위를 정의 할 수 있으므로 사용자 정의가 가능한 편리한 단위를 사용할 수 있습니다. 사용자는 압력이 게이지 또는 절대 단위로 정의되는지 여부도 지정해야합니다. 기본 시뮬레이션 단위는 기본 설정에서 설정할 수 있습니다. 단위를 완전히 정의하면 FLOW-3D 가 물리량의 기본값을 정의하고 범용 상수를 설정하여 사용자가 요구하는 작업량을 최소화 할 수 있습니다.

    Shallow water model

    Manning’s roughness in shallow water model

    Manning의 거칠기 계수는 지형 표면의 전단 응력 평가를 위해 천수(shallow water) 모델에서 구현되었습니다. 표면 결함의 크기를 기반으로 기존 거칠기 모델을 보완하며 이 모델과 함께 사용할 수 있습니다. 표준 거칠기와 마찬가지로 매닝 계수는 구성 요소 또는 하위 구성 요소의 속성이거나 지형 래스터 데이터 세트에서 가져올 수 있습니다.

    Mesh generation

    하단 및 상단 경계 좌표의 정의만으로 수직 방향의 메시 설정이 단순화되었습니다.

    Component transformations

    사용자는 이제 여러 하위 구성 요소로 구성된 구성 요소에 회전, 변환 및 스케일링 변환을 적용하여 복잡한 형상 어셈블리 설정 프로세스를 단순화 할 수 있습니다. GMO (General Moving Object) 구성 요소의 경우, 이러한 변환을 구성 요소의 대칭 축과 정렬되도록 신체에 맞는 좌표계에 적용 할 수 있습니다.

    Changing the number of threads at runtime

    시뮬레이션 중에 솔버가 사용하는 스레드 수를 변경하는 기능이 런타임 옵션 대화 상자에 추가되어 사용 가능한 스레드를 추가하거나 다른 태스크에 자원이 필요한 경우 스레드 수를 줄일 수 있습니다.

    Probe-controlled heat sources

    활성 시뮬레이션 제어가 형상 구성 요소와 관련된 heat sources로 확장되었습니다. 히스토리 프로브로 열 방출을 제어 할 수 있습니다.

    Time-dependent temperature at sources     

    질량 및 질량 / 운동량 소스의 유체 온도는 이제 테이블 입력을 사용하여 시간의 함수로 정의 할 수 있습니다.

    Emissivity coefficients

    공극으로의 복사 열 전달을위한 방사율 계수는 이제 사용자가 방사율과 스테판-볼츠만 상수를 지정하도록 요구하지 않고 직접 정의됩니다. 후자는 이제 단위 시스템을 기반으로 솔버에 의해 자동으로 설정됩니다.

    Output

    • 등속 필드 솔버 옵션을 사용할 때 유량 속도를 선택한 데이터 로 출력 할 수 있습니다 .
    • 벽 접착력으로 인한 지오메트리 구성 요소의 토크 는 기존 벽 접착력의 출력 외에도 일반 이력 데이터에 별도의 수량으로 출력됩니다.
    • 난류 모델 출력이 요청 될 때 난류 에너지 및 소산과 함께 전단 속도 및 y +가 선택된 데이터로 자동 출력됩니다 .
    • 공기 유입 모델 출력에 몇 가지 수량이 추가되었습니다. 자유 표면을 포함하는 모든 셀에서 혼입 된 공기 및 빠져 나가는 공기의 체적 플럭스가 재시작 및 선택된 데이터로 출력되어 사용자에게 공기가 혼입 및 탈선되는 위치 및 시간에 대한 자세한 정보를 제공합니다. 전체 계산 영역 및 각 샘플링 볼륨 에 대해이 두 수량의 시간 및 공간 통합 등가물 이 일반 히스토리 로 출력됩니다.
    • 솔버의 출력 파일 flsgrf 의 최종 크기 는 시뮬레이션이 끝날 때보 고됩니다.
    • 2 유체 시뮬레이션의 경우, 기존의 출력 수량 유체 체류 시간 및 유체 가 이동 한 거리는 이제 유체 # 1 및 # 2와 유체의 혼합물에 대해 별도로 계산됩니다.
    • 질량 입자의 경우 각 종의 총 부피와 질량이 계산되어 전체 계산 영역, 샘플링 볼륨 및 플럭스 표면에 대한 일반 히스토리 로 출력되어 입자 종 수에 대한 현재 출력을 보완합니다.
    • 예를 들어 사용자가 가스 미순환을 식별하고 연료 탱크의 환기 시스템을 설계하는 데 도움이 되도록 마지막 국부적 가스 압력이 옵션 출력량으로 추가되었습니다. 이 양은 유체가 채워지기 전에 셀의 마지막 간극 압력을 기록하며, 단열 버블 모델과 함께 사용됩니다.

    New Customizable Source Routines

    사용자 정의 가능한 새로운 소스 루틴이 추가되었으며 사용자의 개발 환경에서 액세스 할 수 있습니다.

    소스 루틴 이름설명
    cav_prod_cal캐비 테이션 생산 및 확산 속도
    sldg_uset슬러지 정착 속도
    phchg_mass_flux증발 및 응축에 의한 질량 흐름
    flhtccl유체#1과#2사이의 열 전달 계수
    dsize_cal2상 유동에서의 동적 낙하 크기 모델의 충돌 및 이탈율
    elstc_custom.점탄성 유체에 대한 응력 방정식의 소스 용어

    Brand New User Interface

    FLOW-3D의 사용자 인터페이스가 완전히 재설계되어 사용자의 작업 흐름을 획기적으로 간소화하는 최신의 타일 구조를 제공합니다.

    Dock widgets 설정

    Physics, Fluids, Mesh 및 FAVOR ™를 포함한 모든 설정 작업이 형상 창 주위의 dock widgets으로 변환되어 모델 설정을 단일 탭으로 압축 할 수 있습니다. 이 전환을 통해 이전 버전의 복잡한 트리가 훨씬 깔끔하고 효율적인 메뉴 표시로 바뀌어 모델 설정 탭을 떠나지 않고도 모든 매개 변수에 쉽게 액세스 할 수 있습니다.

    New Model Setup icons
    With our new Model Setup design comes new icons, representing each step of the setup process.
    New Physics icons
    Our Physics icons are designed to be easily differentiated from one another at a glance, while providing clear visual representation of each model’s purpose and use.

    RSS feed

    새 RSS 피드부터 FLOW-3D v12.0 의 시뮬레이션 관리자 탭이 개선되었습니다 . FLOW-3D 를 시작하면 사용자에게 Flow Science의 최신 뉴스, 이벤트 및 블로그 게시물이 표시됩니다.

    Configurable simulation monitor

    시뮬레이션을 실행할 때 중요한 작업은 모니터링입니다. FLOW-3Dv12.0에서는 사용자가 시뮬레이션을 더 잘 모니터링할 수 있도록 Simulation Manager의 플로팅 기능이 향상되었습니다. 사용자는 시뮬레이션 런타임 그래프를 통해 모니터링할 사용 가능한 모든 일반 기록 데이터 변수를 선택하고 각 그래프에 여러 변수를 추가할 수 있습니다. 이제 런타임에서 사용할 수 있는 일반 기록 데이터는 다음과 같습니다.

    • 최소/최대 유체 온도
    • 프로브 위치의 온도
    • 유동 표면 위치에서의 유량
    • 시뮬레이션 진단(예:시간 단계, 안정성 한계)
    Runtime plots of the flow rate at the gates of the large dam / Large dam with flux surfaces at the gates

    Conforming mesh visualization

    사용자는 이제 새로운 FAVOR ™ 독 위젯을 통해 적합한 메쉬 블록을 시각화 할 수 있습니다 .

    Large raster and STL data

    데이터를 처리하는 데 걸리는 시간으로 인해 큰 형상 데이터를 처리하는 것은 어려울 수 있습니다. 대형 지오메트리 데이터를 처리하는 데 여전히 상당한 시간이 소요될 수 있지만 FLOW-3D는 이제 이러한 대형 데이터 세트를 백그라운드 작업으로로드하여 사용자가 데이터를 처리하는 동안 완벽하게 응답하고 중단없는 인터페이스에서 계속 작업 할 수 있습니다.

    Sediment Transport Model

    Sediment Transport Model

    Sediment Transport Model

    FLOW-3D의 침전물 이송 모델을 사용하여 세굴 및 침전물을 평가할 수 있으며, 여기서 3차원 유량 구성 요소가 세굴 프로세스를 주도하고 있습니다. Flow-3D의 유체역학 모델은 유체물리학을 설명하는 정전기적이지 않은 레이놀즈-평균화된 Navier-Stokes 방정식을 완벽하게 해결합니다. 유체역학적 솔버는 침전물 운반 모듈과 완전히 결합되어 있어 침전물 운반 및 비접착 토양의 부유식 침식, 인포테인먼트 및 침식을 시뮬레이션합니다(Wei et al., 2014). 베드로드, 인포테인먼트 및 정착 프로세스에 사용되는 모든 경험적 관계는 완전히 사용자 정의 가능하며, 최대 10개의 침전물 종(곡물 크기, 질량 밀도, 임계 전단 응력 등 서로 다른 특성을 가진)을 정의할 수 있습니다. FLOW-3D는 짧은 경과 시간 척도에 대한 국부적 스쿠어를 시뮬레이션하는 데 이상적입니다.

    FLOW-3D‘s Sediment Transport model can be used to evaluate scour and deposition, where three-dimensional flow components are driving the scouring process. FLOW-3D’s hydrodynamic model solves the full unsteady non-hydrostatic Reynolds-averaged Navier-Stokes equations that describe the flow physics. The hydrodynamic solver is fully coupled with a sediment transport module that simulates bedload and suspended sediment transport, entrainment and erosion for non-cohesive soils (Wei et al., 2014). All empirical relationships used in bedload, entrainment and settling processes are fully customizable, and up to 10 different sediment species (with different properties such as grain size, mass density and critical shear stress) can be defined. FLOW-3D is ideal for simulating local scour over short episodic time scales.

    Modeling Capabilities
    – Unsteady 3D mobile bed modeling
    – Bedload and suspended sediment transport
    – Non-cohesive sediment
    – 10 individual grain size fractions
    – Suspended sediment settling and entrainment
    – Critical angle of repose
    Applications
    – River and coastal morphodynamics
    – Bridge pier and abutment scour
    – Local scour at hydraulic structures
    – Sedimentation basins
    – Reservoir flushing

    Sediment Transport Model

    Sentral Transport 모델은 8.0 버전(Brethour, 2009년)에서 처음 도입되었으며, 11.1 버전(Wei et al., 2014년), 가장 최근에는 12.0 버전(Flow Science, 2019년)에서 광범위한 개정을 거쳤습니다. 숫자 모델에서 시뮬레이션된 물리적 프로세스의 개략도가 아래에 나와 있습니다.

    The Sediment Transport model was first introduced in version 8.0 (Brethour, 2009), and has gone through extensive revisions in version 11.1 (Wei et al., 2014), and most recently in version 12.0 (Flow Science, 2019). A schematic of the physical processes simulated in the numerical model is illustrated below.

    The different processes modeled by the Sediment Transport Model.

    수치 모델에서 침전물은 포장된 Bed로서 일시 중단된 상태로 존재할 수 있습니다. 포장된 Bed는 PRIPT™ 기법을 사용하여 복잡한 솔리드 경계(Hirt 및 Sicilian, 1985)에 표현된 지울 수 없는 솔리드 객체입니다. 이것은 유체역학 용해기의 고체 물체를 나타내는 데 사용되는 방법과 동일합니다. 포장된 Bed의 형태학적 변화는 침전물 질량의 보존에 의해 좌우됩니다.

    In the numerical model, sediment can exist as packed bed and in a suspended state. A packed bed is an erodible solid object that is represented using the FAVOR™ technique for complex solid boundaries (Hirt and Sicilian, 1985). This is the same method used to represent solid objects in the hydrodynamic solver. The morphological change in the packed bed is governed by the conservation of sediment mass.

    형태학적 변경은 모형에 숫자로 표시되는 여러 가지 물리적 프로세스에 의해 제어됩니다. 이러한 프로세스에는 베드로드 운송, 인포테인먼트 및 증착이 포함됩니다. 베드로드 이송은 침전물이 서스펜션에 전달되지 않고 채널을 따라 횡방향으로 이동하는 물리적 과정입니다. 인포테인먼트란 난류 에디가 패킹 베드 상단의 곡물을 제거하고 일시 중단된 상태로 전환하는 과정입니다. 포장이란 곡물이 현수막에서 안착되어 포장된 침대에 퇴적하는 과정입니다. 수치 모델에서 이것은 일시 중단된 상태에서 포장된 베드 상태로의 전환입니다.

    The morphological changes are governed by several different physical processes that are represented numerically in the model. These processes include bedload transport, entrainment and deposition. Bedload transport is the physical process of sediment moving laterally along the channel without being carried into suspension. Entrainment is the process by which turbulent eddies remove the grains from the top of the packed bed and transition to the suspended state. Packing is the process of grains settling out of suspension and depositing onto the packed bed. In the numerical model, this is the transition from the suspended to the packed bed state.

    인포테인먼트 및 패킹의 상대적 비율은 포장된 베드와 부유 상태 사이의 침전물 질량 교환을 제어합니다. 이 모델은 Meyer-Peter Müler(1948), Nielsen(1992) 또는 Van Rijn(1984)의 방정식을 사용하여 베드 인터페이스가 포함된 각 메시 셀에서 베드로드 전송을 계산합니다. 메쉬 셀에서 이웃의 각 메쉬 셀로 이동하는 곡물의 양을 결정하기 위해 하위 메쉬 방법이 사용됩니다. 인포테인먼트에서 곡물의 리프팅 속도는 Winterwerp 등(1992)의 방정식을 사용하여 계산됩니다. 안착 속도는 Soulsby(1997년)를 사용하여 계산됩니다. 베드 인터페이스가 포함된 메시 셀에서 인터페이스의 위치, 방향 및 면적을 계산하여 베드 전단 응력, 무차원 전단 응력, 베드로드 전송 속도 및 인포테인먼트 속도를 결정합니다. 3D 난류 흐름의 베드 전단 응력은 표준 벽 함수를 사용하여 중간 곡물 크기에 비례하는 베드 표면 거칠기를 고려하여 평가됩니다.

    The relative rates of entrainment and packing control the exchange of sediment mass between the packed bed and suspended states. The model calculates bedload transport in each mesh cell containing the bed interface using the equation of Meyer-Peter Müller (1948), Nielsen (1992) or Van Rijn (1984). A sub-mesh method is employed to determine the amount of grains moving from the mesh cell into each mesh cell in its neighbor. The lifting velocity of grains in entrainment is calculated using the equation of Winterwerp et al. (1992). The settling velocity is calculated using Soulsby (1997). In the mesh cells containing the bed interface, location, orientation and area of the interface are calculated to determine the bed shear stress, dimensionless shear stress, bedload transport rates and entrainment rates. Bed shear stress in 3D turbulent flows is evaluated using the standard wall function with consideration of bed surface roughness that is proportional to the median grain size.

    부유된 침전물은 유체의 스칼라 질량 농도로 표시됩니다. 농도는 주어진 셀에서 균일한 것으로 가정되며 유체 셀 밀도 및 점도와 결합됩니다. 각 종에 대해, 부유 침전물 농도는 수송 방정식을 풀어서 계산됩니다.

    The suspended sediment is represented as a scalar mass concentration in the fluid. The concentration is assumed to be uniform in a given cell and is coupled with the fluid cell density and viscosity. For each species, the suspended sediment concentration is calculated by solving a transport equation.

    Validations

    다음 5가지 검증 사례는 실험 데이터와 FLOW-3D의 침전물 이송 모델의 시뮬레이션 결과를 비교합니다.

    마오(1986년)
    Mao는 수중 수평 파이프라인 아래 침대의 무서운 프로파일을 얻기 위해 실험 작업을 수행했습니다. 아래 그림은 FLOW-3D를 사용하여 얻은 결과와 실험 결과를 비교합니다.

    그림 A는 파이프라인 아래의 최대 scour깊이를 시간 경과에 따라 비교하는 반면, 그림 B ~ F는 스터디의 scour프로필(빨간색 점으로 표시됨)과 FLOW-3D 프로필을 오버레이합니다.
    Chatterjee et al. (1994)

    수평 제트 침수로 인해 국부적인 스쿠어 프로파일을 얻기 위한 실험 작업이 수행되었습니다. 아래 그림은 scour구멍 깊이와 둔부 높이에 대한 실험 대 FLOW-3D의 숫자 결과를 시간의 함수로 비교합니다. 이 애니메이션은 scour구멍과 둔부 높이가 최대 1시간 내에 안정된 상태에 도달한다는 것을 보여줍니다.

    Gladstone et al. (1998)

    In these experiments the propagation and deposition patterns of particle-laden flows were studied. The plot below compares experimental versus FLOW-3D simulation results from three different setups, labeled case A (100% 0.025mm size particles), case D (50% 0.069mm and 50% 0.025mm size particles), and case G (100% 0.069mm size particles).

    Faruque et al. (2006)

    이 논문에서, 저자들은 실험을 통해 3차원 벽면 제트기를 물에 잠기게 함으로써 국부적인 악취를 연구했습니다. 아래 표는 세 가지 서로 다른 테일워터 비율에 대한 scour 구멍의 3D 형태학적 변화에 대한 실험과 FLOW-3D 수치 결과를 비교합니다.

    Equilibrium bed elevation changes predicted by the numerical model for a cylindrical pier. (A) Isometric view of scour and deposition adjacent to the pier. (B) Comparison between numerical results (top) and physical model measurements (bottom).
    Equilibrium bed elevation changes predicted by the numerical model for the diamond pier. (A) Isometric view of scour and deposition adjacent to the pier. (B) Comparison between numerical results (top) and physical model measurements (bottom).

    In this paper, the authors studied local scour by submerged three-dimensional wall jets via experiments. The table below compares the experimental versus FLOW-3D numerical results for 3D morphological changes in the scour hole for three different tailwater ratios.

    References

    Brethour, J.M., Hirt, C.W., 2009, Drift Model for Two-Component Flows,  FSI-14-TN-83, Flow Science, Inc.

    Chatterjee, S.S., Ghosh, S.N., and Chatterjee M., 1994, Local scour due to submerged horizontal jet, Journal of Hydraulic Engineering, 120(8), pp. 973-992.

    Faruque, M.A.A., Sarathi, P., and Balachandar R., 2006, Clear Water Local Scour by Submerged Three-Dimensional Wall Jets : Effect of Tailwater Depth, Journal of Hydraulic Engineering, 132(6), pp. 575-580.

    Flow Science, 2019, FLOW-3D Version 12.0 User Manual, Santa Fe, NM: Flow Science, Inc. https://www.flow3d.com

    Fox, B. and Feurich, R., 2019, CFD Analysis of Local Scour at Bridge PiersFederal Interagency Sedimentation and Hydrologic Modeling Conference (SEDHYD), Reno, NV.

    Gladstone, C., Phillips, J.C., and Sparks R.S.J., 1998, Experiments on bidisperse, constant-volume gravity currents: propagation and sediment deposition, Sedimentology 45, pp. 833-843.

    Hirt, C.W. and Sicilian, J.M., 1985, A porosity technique for the definition of obstacles in rectangular cell meshes, 4th International Conference on Numerical Ship Hydrodynamics, Washington, D.C.

    Khosronejad, A., Kang, S., & Sotiropoulos, F., 2012. Experimental and computational investigation of local scour around bridge piers, Advances in Water Resources, 37, pp. 73-85.

    Mao, Y., 1986. The interaction between a pipeline and an erodible bed, PhD thesis, Institute of Hydrodynamics and Hydraulic Engineering, Technical University of Denmark, Lyngby, Denmark.

    Meyer-Peter, E. and Müller, R., 1948, Formulas for bed-load transport, Proceedings of the 2nd Meeting of the International Association for Hydraulic Structures Research. pp. 39–64.

    Nielsen, P., 1992, Coastal bottom boundary layers and sediment transport (Vol. 4). World scientific.

    Soulsby, R., 1997, Dynamics of Marine Sands, Thomas Telford Publications, London.

    Van Rijn, L. C., 1984, Sediment Transport, Part I: Bed load transport, Journal of Hydraulic Engineering 110(10), pp. 1431-1456.

    Wei, G., Brethour, J.M., Grüenzner M., and Burnham, J., 2014, The Sediment Scour Model in FLOW-3D, Technical Note FSI-14-TN-99, Flow Science, Inc.

    Winterwerp, J.C., Bakker, W.T., Mastbergen, D.R. and Van Rossum, H., 1992, Hyperconcentrated sand-water mixture flows over erodible bed, Journal of Hydraulic Engineering, 118(11), pp. 1508–1525.

    Additive Manufacturing & Welding Bibliography

    Additive Manufacturing & Welding Bibliography

    다음은 적층 제조 및 용접 참고 문헌의 기술 문서 모음입니다. 이 모든 논문에는 FLOW-3D AM 결과가 나와 있습니다. FLOW-3D AM을 사용하여 적층 제조, 레이저 용접 및 기타 용접 기술에서 발견되는 프로세스를 성공적으로 시뮬레이션하는 방법에 대해 자세히 알아보십시오.

    2024년 11월 20일 update

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    63-24 Haodong Chen, Xin Lin, Yajing Sun, Shuhao Wang, Kunpeng Zhu, Binbin Dan, Revealing formation mechanism of end of process depression in laser powder bed fusion by multi-physics meso-scale simulation, Virtual and Physical Prototyping, 19.1; e2326599, 2024. doi.org/10.1080/17452759.2024.2326599

    57-24 Masayuki Okugawa, Kenji Saito, Haruki Yoshima, Katsuhiko Sawaizumi, Sukeharu Nomoto, Makoto Watanabe, Takayoshi Nakano, Yuichiro Koizumi, Solute segregation in a rapidly solidified Hastelloy-X Ni-based superalloy during laser powder bed fusion investigated by phase-field and computational thermal-fluid dynamics simulations, Additive Manufacturing, 84; 104079, 2024. doi.org/10.1016/j.addma.2024.104079

    51-24 Jeongho Yang, Dongseok Kang, Si Mo Yeon, Yong Son, Sang Hu Park, Interval island laser-scanning strategy of Ti–6Al–4V part additively manufactured for anisotropic stress reduction, International Journal of Precision Engineering and Manufacturing, 25; pp. 1087-1099, 2024. doi.org/10.1007/s12541-024-00967-z

    50-24 James Lamb, Ruben Ochoa, Adriana Eres-Castellanos, Jonah Klemm-Toole, McLean P. Echlin, Tao Sun, Kamel Fezzaa, Amy Clarke, Tresa M. Pollack, Quantification of melt pool dynamics and microstructure during simulated additive manufacturing, Scripta Materialia, 245; 116036, 2024. doi.org/10.1016/j.scriptamat.2024.116036

    41-24 Xiong Zhang, Chunjin Wang, Benny C.F. Cheung, Gaoyang Mi, Chunming Wang, Ultrafast laser ablation of tungsten carbide: Quantification of threshold range and interpretation of feature transition, Journal of the American Ceramic Society, 107.6; pp. 3724-3734, 2024. doi.org/10.1111/jace.19718

    38-24 Hao-Ping Yeh, Mohamad Bayat, Amirhossein Arzani, Jesper H. Hattel, Accelerated process parameter selection of polymer-based selective laser sintering via hybrid physics-informed neural network and finite element surrogate modelling, Applied Mathematical Modelling, 130; pp. 693-712, 2024. doi.org/10.1016/j.apm.2024.03.030

    34-24 Khalid El Abbaoui, Issam Al Korachi, Mostapha El Jai, Berin Šeta, Md. Tusher Mollah, 3D concrete printing using computational fluid dynamics: Modeling of material extrusion with slip boundaries, Journal of Manufacturing Processes, 118; pp. 448-459, 2024. doi.org/10.1016/j.jmapro.2024.03.042

    33-24 Hao Lu, Lida Zhu, Pengsheng Xue, Boling Yan, Yanpeng Hao, Zhichao Yang, Jinsheng Ning, Chuanliang Shi, Hao Wang, Ultrasonic machining response and improvement mechanism for differentiated bio-CoCrMo alloys manufactured by directed energy deposition, Journal of Materials Science & Technology, 193; pp. 226-243, 2024. doi.org/10.1016/j.jmst.2023.12.037

    32-24 Yinghang Liu, Zhe Song, Yi Guo, Gaoming Zhu, Yunhao Fan, Huamiao Wang, Wentao Yan, Xiaoqin Zeng, Leyun Wang, Simultaneously enhancing strength and ductility of LPBF Ti alloy via trace Y2O3 nanoparticle addition, Journal of Materials Science & Technology, 191; pp. 146-156, 2024. doi.org/10.1016/j.jmst.2024.01.011

    27-24 Zehui Liu, Yiyang Hu, Mingyang Zhang, Wei Zhang, Jun Wang, Wenbo Lei, Chunming Wang, Surface morphology evolution mechanisms of pulse laser polishing mold steel, International Journal of Mechanical Sciences, 269; 109039, 2024. doi.org/10.1016/j.ijmecsci.2024.109039

    25-24 Muhammad Arif Mahmood, Kashif Ishfaq, Marwan Khraisheh, Inconel-718 processing windows by directed energy deposition: a framework combining computational fluid dynamics and machine learning models with experimental validation, The International Journal of Advanced Manufacturing Technology, 130; pp. 3997-4011, 2024. doi.org/10.1007/s00170-024-12980-7

    24-24   Jinsheng Ning, Lida Zhu, Shuhao Wang, Zhichao Yang, Peihua Xu, Pengsheng Xue, Hao Lu, Miao Yu, Yunhang Zhao, Jiachen Li, Susmita Bose, Amit Bandyopadhyay, Printability disparities in heterogeneous material combinations via laser directed energy deposition: a comparative study, International Journal of Extreme Manufacturing, 6; 025001, 2024. doi.org/10.1088/2631-7990/ad172f

    18-24   Delong Jia, Dong Zhou, Peng Yi, Chuanwei Zhang, Junru Li, Yankuo Guo, Shengyue Zhang, Yanhui Li, Splat deposition stress formation mechanism of droplets impacting onto texture, International Journal of Mechanical Sciences, 266; 109002, 2024. doi.org/10.1016/j.ijmecsci.2024.109002

    11-24   Dae Gune Jung, Ji Young Park, Choong Mo Ryu, Jong Jin Hwang, Seung Jae Moon, Numerical study of laser welding of 270 μm thick silicon-steel sheets for electrical motors, Metals, 14.1; 24, 2024. doi.org/10.3390/met14010024

    8-24   Zhifu Yao, Longke Bao, Mujin Yang, Yuechao Chen, Minglin He, Jiang Yi, Xintong Yang, Tao Yang, Yilu Zhao, Cuiping Wang, Zheng Zhong, Shuai Wang, Xingjun Liu, Thermally stabe strong <101> texture in additively manufactured cobalt-based superalloys, Scripta Materialia, 242; 115942, 2024. doi.org/10.1016/j.scriptamat.2023.115942

    5-24   Xi Shu, Chunyu Wang, Guoqing Chen, Chunju Wang, Lining Sun, Pre-melted electron beam freeform fabrication additive manufacturing: modeling and numerical simulation, Welding in the World, 68; pp. 163-176, 2024. doi.org/10.1007/s40194-023-01647-8

    4-24   Lin Gao, Andrew C. Chuang, Peter Kenesei, Zhongshu Ren, Lilly Balderson, Tao Sun, An operando synchrotron study on the effect of wire melting state on solidification microstructures of Inconel 718 in wire-laser directed energy deposition, International Journal of Machine Tools and Manufacture, 194; 104089, 2024. doi.org/10.1016/j.ijmachtools.2023.104089

    3-24 Kunjie Dai, Xing He, Decheng Kong, Chaofang Dong, Multi-physical field simulation to yield defect-free IN718 alloy fabricated by laser powder bed fusion, Materials Letters, 355; 135437, 2024. doi.org/10.1016/j.matlet.2023.135437

    2-24 You Wang, Yinkai Xie, Huaixue Li, Caiyou Zeng, Ming Xu, Hongqiang Zhang, In-situ monitoring plume, spattering behavior and revealing their relationship with melt flow in laser powder bed fusion of nickel-based superalloy, Journal of Materials Science & Technology, 177; pp. 44-58, 2024. doi.org/10.1016/j.jmst.2023.07.068

    1-24 Yukai Chen, Hongtu Xu, Yu Lu, Yin Wang, Shuangyuzhou Wang, Ke Huang, Qi Zhang, Prediction of microstructure for Inconel 718 laser welding process using multi-scale model, Proceedings of the 14th International Conference on the Technology of Plasticity – Current Trends in the Technology of Plasticity, pp. 713-722, 2024. doi.org/10.1007/978-3-031-41341-4_75

    211-23 Giovanni Chianese, Qamar Hayat, Sharhid Jabar, Pasquale Franciosa, Darek Ceglarek, Stanislao Patalano, A multi-physics CFD study to investigate the impact of laser beam shaping on metal mixing and molten pool dynamics during laser welding of copper to steel for battery terminal-to-casing connections, Journal of Materials Processing Technology, 322; 118202, 2023. doi.org/10.1016/j.jmatprotec.2023.118202

    207-23 Dong Liu, Jiaqi Pei, Hua Hou, Xiaofeng Niu, Yuhong Zhao, Optimizing solidification dendrites and process parameters for laser powder bed fusion additive manufacturing of GH3536 superalloy by finite volume and phase-field method, Journal of Materials Research and Technology, 27; pp. 3323-3338, 2023. doi.org/10.1016/j.jmrt.2023.10.188

    206-23 Houshang Yin, Jingfan Yang, Ralf D. Fischer, Zilong Zhang, Bart Prorok, Lang Yuan, Xiaoyuan Lou, Pulsed laser additive manufacturing for 316L stainless steel: a new approach to control subgrain cellular structure, JOM, 75; pp. 5027-5036, 2023. doi.org/10.1007/s11837-023-06177-8

    205-23 Francis Ogoke, William Lee, Ning-Yu Kao, Alexander Myers, Jack Beuth, Jonathan Malen, Amir Barati Farimani, Convolutional neural networks for melt depth prediction and visualization in laser powder bed fusion, The International Journal of Advanced Manufacturing Technology, 129; pp. 3047-3062, 2023. doi.org/10.1007/s00170-023-12384-z

    202-23 Habib Hamed Zargari, Kazuhiro Ito, Abhay Sharma, Effect of workpiece vibration frequency on heat distribution and material flow in the molten pool in tandem-pulsed gas metal arc welding, The International Journal of Advanced Manufacturing Technology, 129; pp. 2507-2522, 2023. doi.org/10.1007/s00170-023-12424-8

    199-23 Yukai Chen, Yin Wang, Hao Li, Yu Lu, Bin Han, Qi Zhang, Effects of process parameters on the microstructure of Inconel 718 during powder bed fusion based on cellular automata approach, Virtual and Physical Prototyping, 18.1; e2251032, 2023. doi.org/10.1080/17452759.2023.2251032

    197-23 Qiong Wu, Chuang Qiao, Yuhang Wu, Zhe Liu, Xiaodan Li, Ju Wang, Xizhong An, Aijun Huang, Chao Voon Samuel Lim, Numerical investigation on the reuse of recycled powders in powder bed fusion additive manufacturing, Additive Manufacturing, 77; 103821, 2023. doi.org/10.1016/j.addma.2023.103821

    196-23 Daicong Zhang, Chunhui Jing, Wei Guo, Yuan Xiao, Jun Luo, Lehua Qi, Microchannels formed using metal microdroplets, Micromachines, 14.10; 1922, 2023. doi.org/10.3390/mi14101922

    195-23 Trong-Nhan Le, Santosh Rauniyar, V.H. Nismath, Kevin Chou, An investigation into the effects of contouring process parameters on the up-skin surface characteristics in laser powder-bed fusion process, Manufacturing Letters, 35; Supplement, pp. 707-716, 2023. doi.org/10.1016/j.mfglet.2023.08.085

    194-23 Kyubok Lee, Teresa J. Rinker, Masoud M. Pour, Wayne Cai, Wenkang Huang, Wenda Tan, Jennifer Bracey, Jingjing Li, A study on cracks and IMCs in laser welding of Al and Cu, Manufacturing Letters, 35; Supplement, pp. 221-231, 2023. doi.org/10.1016/j.mfglet.2023.08.026

    192-23 Kunjie Dai, Xing He, Wei Zhang, Decheng Kong, Rong Guo, Minlei Hu, Ketai He, Chaofang Dong, Tailoring the microstructure and mechanical properties for Hastelloy X alloy by laser powder bed fusion via scanning strategy, Materials & Design, 235; 112386, 2023. doi.org/10.1016/j.matdes.2023.112386

    191-23 Jun Du, Daqing Wang, Jimiao He, Yongheng Zhang, Zhike Peng, Influence of droplet size and ejection frequency on molten pool dynamics and deposition morphology in TIG-aided droplet deposition manufacturing, International Communications in Heat and Mass Transfer, 148; 107075, 2023. doi.org/10.1016/j.icheatmasstransfer.2023.107075

    188-23 Jin-Hyeong Park, Du-Song Kim, Dae-Won Cho, Jaewoong Kim, Changmin Pyo, Influence of thermal flow and predicting phase transformation on various welding positions, Heat and Mass Transfer, 2023. doi.org/10.1007/s00231-023-03429-w

    184-23 Lin Gao, Jishnu Bhattacharyya, Wenhao Lin, Zhongshu Ren, Andrew C. Chuang, Pavel D. Shevchenko, Viktor Nikitin, Ji Ma, Sean R. Agnew, Tao Sun, Tailoring material microstructure and property in wire-laser directed energy deposition through a wiggle deposition strategy, Additive Manufacturing, 77; 103801, 2023. doi.org/10.1016/j.addma.2023.103801

    182-23 Liping Guo, Hanjie Liu, Hongze Wang, Qianglong Wei, Jiahui Zhang, Yingyan Chen, Chu Lun Alex Leung, Qing Lian, Yi Wu, Yu Zou, Haowei Wang, A high-fidelity comprehensive framework for the additive manufacturing printability assessment, Journal of Manufacturing Processes, 105; pp. 219-231, 2023. doi.org/10.1016/j.jmapro.2023.09.041

    172-23 Liping Guo, Hanjie Liu, Hongze Wang, Qianglong Wei, Yakai Xiao, Zijue Tang, Yi Wu, Haowei Wang, Identifying the keyhole stability and pore formation mechanisms in laser powder bed fusion additive manufacturing, Journal of Materials Processing Technology, 321; 118153, 2023. doi.org/10.1016/j.jmatprotec.2023.118153

    171-23 Yuhang Wu, Qiong Wu, Meng Li, Ju Wang, Dengzhi Yao, Hao Luo, Xizhong An, Haitao Fu, Hao Zhang, Xiaohong Yang, Qingchuan Zou, Shujun Li, Haibin Ji, Xing Zhang, Numerical investigation on effects of operating conditions and final dimension predictions in laser powder bed fusion of molybdenum, Additive Manufacturing, 76; 103783, 2023. doi.org/10.1016/j.addma.2023.103783

    158-23 K. El Abbaoui, I. Al Korachi, M.T. Mollah, J. Spangenberg, Numerical modelling of planned corner deposition in 3D concrete printing, Archives of Materials Science and Engineering, 121.2; pp. 71-79, 2023. doi.org/10.5604/01.3001.0053.8488

    156-23 Liping Guo, Hanjie Liu, Hongze Wang, Valentino A.M. Cristino, C.T. Kwok, Qianglong Wei, Zijue Tang, Yi Wu, Haowei Wang, Deepening the scientific understanding of different phenomenology in laser powder bed fusion by an integrated framework, International Journal of Heat and Mass Transfer, 216; 124596, 2023. doi.org/10.1016/j.ijheatmasstransfer.2023.124596

    154-23 Zhiyong Li, Xiuli He, Shaoxia Li, Xinfeng Kan, Yanjun Yin, Gang Yu, Sulfur-induced transitions of thermal behavior and flow dynamics in laser powder bed fusion of 316L powders, Thermal Science and Engineering Progress, 45; 102072, 2023. doi.org/10.1016/j.tsep.2023.102072

    149-23 Shardul Kamat, Wayne Cai, Teresa J. Rinker, Jennifer Bracey, Liang Xi, Wenda Tan, A novel integrated process-performance model for laser welding of multi-layer battery foils and tabs, Journal of Materials Processing Technology, 320; 118121, 2023. doi.org/10.1016/j.jmatprotec.2023.118121

    148-23 Reza Ghomashchi, Shahrooz Nafisi, Solidification of Al12Si melt pool in laser powder bed fusion, Journal of Materials En gineering and Performance, 2023. doi.org/10.1007/s11665-023-08502-3

    133-23 Hesam Moghadasi, Md Tusher Mollah, Deepak Marla, Hamid Saffari, Jon Spangenberg, Computational fluid dynamics modeling of top-down digital light processing additive manufacturing, Polymers, 15.11; 2459, 2023. doi.org/10.3390/polym15112459

    131-23 Luca Santoro, Raffaella Sesana, Rosario Molica Nardo, Francesca Curà, In line defect detection in steel welding process by means of thermography, Experimental Mechanics in Engineering and Biomechanics – Proceedings ICEM20, 19981, 2023.

    128-23 Md Tusher Mollah, Raphaël Comminal, Wilson Ricardo Leal da Silva, Berin Šeta, Jon Spangenberg, Computational fluid dynamics modelling and experimental analysis of reinforcement bar integration in 3D concrete printing, Cement and Concrete Research, 173; 107263, 2023. doi.org/10.1016/j.cemconres.2023.107263

    123-23 Arash Samaei, Zhongsheng Sang, Jennifer A. Glerum, Jon-Erik Mogonye, Gregory J. Wagner, Multiphysics modeling of mixing and material transport in additive manufacturing with multicomponent powder beds, Additive Manufacturing, 67; 103481, 2023. doi.org/10.1016/j.addma.2023.103481

    122-23 Chu Han, Ping Jiang, Shaoning Geng, Lingyu Guo, Kun Liu, Inhomogeneous microstructure distribution and its formation mechanism in deep penetration laser welding of medium-thick aluminum-lithium alloy plates, Optics & Laser Technology, 167; 109783, 2023. doi.org/10.1016/j.optlastec.2023.109783

    111-23 Alexander J. Myers, Guadalupe Quirarte, Francis Ogoke, Brandon M. Lane, Syed Zia Uddin, Amir Barati Farimani, Jack L. Beuth, Jonathan A. Malen, High-resolution melt pool thermal imaging for metals additive manufacturing using the two-color method with a color camera, Additive Manufacturing, 73; 103663, 2023. doi.org/10.1016/j.addma.2023.103663

    107-23 M. Mohsin Raza, Yu-Lung Lo, Hua-Bin Lee, Chang Yu-Tsung, Computational modeling of laser welding for aluminum–copper joints using a circular strategy, Journal of Materials Research and Technology, 25; pp. 3350-3364, 2023. doi.org/10.1016/j.jmrt.2023.06.122

    106-23 H.Z. Lu, L.H. Liu, X. Luo, H.W. Ma, W.S. Cai, R. Lupoi, S. Yin, C. Yang, Formation mechanism of heterogeneous microstructures and shape memory effect in NiTi shape memory alloy fabricated via laser powder bed fusion, Materials & Design, 232; 112107, 2023. doi.org/10.1016/j.matdes.2023.112107

    105-23 Harun Kahya, Hakan Gurun, Gokhan Kucukturk, Experimental and analytical investigation of the re-melting effect in the manufacturing of 316L by direct energy deposition (DED) method, Metals, 13.6; 1144, 2023. doi.org/10.3390/met13061144

    100-23 Dongju Chen, Gang Li, Peng Wang, Zhiqiang Zeng, Yuhang Tang, Numerical simulation of melt pool size and flow evolution for laser powder bed fusion of powder grade Ti6Al4V, Finite Elements in Analysis and Design, 223; 103971, 2023. doi.org/10.1016/j.finel.2023.103971

    97-23 Mahyar Khorasani, Martin Leary, David Downing, Jason Rogers, Amirhossein Ghasemi, Ian Gibson, Simon Brudler, Bernard Rolfe, Milan Brandt, Stuart Bateman, Numerical and experimental investigations on manufacturability of Al–Si–10Mg thin wall structures made by LB-PBF, Thin-Walled Structures, 188; 110814, 2023. doi.org/10.1016/j.tws.2023.110814

    95-23 M.S. Serdeczny, Laser welding of dissimilar materials – simulation driven optimization of process parameters, IOP Conference Series: Materials Science and Engineering, 1281; 012018, 2023. doi.org/10.1088/1757-899X/1281/1/012018

    90-23 Lin Liu, Tubin Liu, Xi Dong, Min Huang, Fusheng Cao, Mingli Qin, Numerical simulation of thermal dynamic behavior and morphology evolution of the molten pool of selective laser melting BN/316L stainless steel composite, Journal of Materials Engineering and Performance, 2023. doi.org/10.1007/s11665-023-08210-y

    89-23 M. P. Serdeczny, A. Jackman, High fidelity modelling of bead geometry in directed energy deposition – simulation driven optimization, Journal of Physics: Conference Series, NOLAMP19, 2023.

    88-23 Lu Wang, Shuhao Wang, Yanming Zhang, Wentao Yan, Multi-phase flow simulation of powder streaming in laser-based directed energy deposition, International Journal of Heat and Mass Transfer, 212; 124240, 2023. doi.org/10.1016/j.ijheatmasstransfer.2023.124240

    80-23 Mahyar Khorasani, AmirHossein Ghasemi, Martin Leary, David Downing, Ian Gibson, Elmira G. Sharabian, Jithin Kozuthala Veetil, Milan Brandt, Stuart Batement, Bernard Rolfe, Benchmark models for conduction and keyhole modes in laser-based powder bed fusion of Inconel 718, Optics & Laser Technology, 164; 109509, 2023. doi.org/10.1016/j.optlastec.2023.109509

    78-23   Md. Tusher Mollah, Raphaël Comminal, Marcin P. Serdeczny, Berin Šeta, Jon Spangenberg, Computational analysis of yield stress buildup and stability of deposited layers in material extrusion additive manufacturing, Additive Manufacturing, 71; 103605, 2023. doi.org/10.1016/j.addma.2023.103605

    76-23   Asif Ur Rehman, Kashif Azher, Abid Ullah, Celal Sami Tüfekci, Metin Uymaz Salamci, Binder jetting of SS316L: a computational approach for droplet-powder interaction, Rapid Prototyping Journal, 2023. doi.org/10.1108/RPJ-08-2022-0264

    75-23   Dengzhi Yao, Ju Wang, Hao Luo, Yuhang Wu, Xizhong An, Thermal behavior and control during multi-track laser powder bed fusion of 316 L stainless steel, Additive Manufacturing, 70; 103562, 2023. doi.org/10.1016/j.addma.2023.103562

    61-23   Yaqing Hou, Hang Su, Hao Zhang, Fafa Li, Xuandong Wang, Yazhou He, Dupeng He, An integrated simulation model towards laser powder bed fusion in-situ alloying technology, Materials & Design, 228; 111795, 2023. doi.org/10.1016/j.matdes.2023.111795

    56-23   Maohong Yang, Guiyi Wu, Xiangwei Li, Shuyan Zhang, Honghong Wang, Jiankang Huang, Influence of heat source model on the behavior of laser cladding pool, Journal of Laser Applications, 35.2; 2023. doi.org/10.2351/7.0000963

    45-23   Daniel Martinez, Philip King, Santosh Reddy Sama, Jay Sim, Hakan Toykoc, Guha Manogharan, Effect of freezing range on reducing casting defects through 3D sand-printed mold designs, The International Journal of Advanced Manufacturing Technology, 2023. doi.org/10.1007/s00170-023-11112-x

    39-23   Peter S. Cook, David J. Ritchie, Determining the laser absorptivity of Ti-6Al-4V during laser powder bed fusion by calibrated melt pool simulation, Optics & Laser Technology, 162; 109247. 2023. doi.org/10.1016/j.optlastec.2023.109247

    36-23   Yixuan Chen, Weihao Wang, Yao Ou, Yingna Wu, Zirong Zhai, Rui Yang, Impact of laser power and scanning velocity on microstructure and mechanical properties of Inconel 738LC alloys fabricated by laser powder bed fusion, TMS 2023 152nd Annual Meeting & Exhibition Supplemental Proceedings, pp. 138-149, 2023. doi.org/10.1007/978-3-031-22524-6_15

    34-23   Chao Kang, Ikki Ikeda, Motoki Sakaguchi, Recoil and solidification of a paraffin droplet impacted on a metal substrate: Numerical study and experimental verification, Journal of Fluids and Structures, 118; 103839, 2023. doi.org/10.1016/j.jfluidstructs.2023.103839

    30-23   Fei Wang, Tiechui Yuan, Ruidi Li, Shiqi Lin, Zhonghao Xie, Lanbo Li, Valentino Cristino, Rong Xu, Bing liu, Comparative study on microstructures and mechanical properties of ultra ductility single-phase Nb40Ti40Ta20 refractory medium entropy alloy by selective laser melting and vacuum arc melting, Journal of Alloys and Compounds, 942; 169065, 2023. doi.org/10.1016/j.jallcom.2023.169065

    29-23   Haejin Lee, Yeonghwan Song, Seungkyun Yim, Kenta Aoyagi, Akihiko Chiba, Byoungsoo Lee, Influence of linear energy on side surface roughness in powder bed fusion electron beam melting process: Coupled experimental and simulation study, Powder Technology, 418; 118292, 2023.

    27-23   Yinan Chen, Bo Li, Double-phase refractory medium entropy alloy NbMoTi via selective laser melting (SLM) additive manufacturing, Journal of Physics: Conference Series, 2419; 012074, 2023. doi.org/10.1088/1742-6596/2419/1/012074

    23-23   Yunwei Gui, Kenta Aoyagi, Akihiko Chiba, Development of macro-defect-free PBF-EB-processed Ti–6Al–4V alloys with superior plasticity using PREP-synthesized powder and machine learning-assisted process optimization, Materials Science and Engineering: A, 864; 144595, 2023. doi.org/10.1016/j.msea.2023.144595

    21-23   Tatsuhiko Sakai, Yasuhiro Okamoto, Nozomi Taura, Riku Saito, Akira Okada, Effect of scanning speed on molten metal behaviour under angled irradiation with a continuous-wave laser, Journal of Materials Processing Technology, 313; 117866, 2023. doi.org/10.1016/j.jmatprotec.2023.117866

    19-23   Gianna M. Valentino, Arunima Banerjee, Alexander lark, Christopher M. Barr, Seth H. Myers, Ian D. McCue, Influence of laser processing parameters on the density-ductility tradeoff in additively manufactured pure tantalum, Additive Manufacturing Letters, 4; 100117, 2023. doi.org/10.1016/j.addlet.2022.100117

    15-23   Runbo Jiang, Zhongshu Ren, Joseph Aroh, Amir Mostafaei, Benjamin Gould, Tao Sun, Anthony D. Rollett, Quantifying equiaxed vs epitaxial solidification in laser melting of CMSX-4 single crystal superalloy, Metallurgical and Materials Transactions A, 54; pp. 808-822, 2023. doi.org/10.1007/s11661-022-06929-2

    14-23   Nguyen Thi Tien, Yu-Lung Lo, M. Mohsin Raza, Cheng-Yen Chen, Chi-Pin Chiu, Optimization of processing parameters for pulsed laser welding of dissimilar metal interconnects, Optics & Laser Technology, 159; 109022, 2023. doi.org/10.1016/j.optlastec.2022.109022

    9-23 Hou Yi Chia, Wentao Yan, High-fidelity modeling of metal additive manufacturing, Additive Manufacturing Technology: Design, Optimization, and Modeling, Ed. Kun Zhou, 2023.

    8-23 Akash Aggarwal, Yung C. Shin, Arvind Kumar, Investigation of the transient coupling between the dynamic laser beam absorptance and the melt pool – vapor depression morphology in laser powder bed fusion process, International Journal of Heat and Mass Transfer, 201.2; 123663, 2023. doi.org/10.1016/j.ijheatmasstransfer.2022.123663

    199-22 Md. Tusher Mollah, Raphaël Comminal, Marcin P. Serdeczny, David B. Pedersen, Jon Spangenberg, Numerical predictions of bottom layer stability in material extrusion additive manufacturing, JOM, 74; pp. 1096-1101, 2022. doi.org/10.1007/s11837-021-05035-9

    198-22 Md. Tusher Mollah, Amirpasha Moetazedian, Andy Gleadall, Jiongyi Yan, Wayne Edgar Alphonso, Raphael Comminal, Berin Seta, Tony Lock, Jon Spangenberg, Investigation on corner precision at different corner angles in material extrusion additive manufacturing: An experimental and computational fluid dynamics analysis, Proceedings of the 33rd Annual Solid Freeform Fabrication Symposium, 2022.

    197-22 Md. Tusher Mollah, Marcin P. Serdeczny, Raphaël Comminal, Berin Šeta, Marco Brander, David B. Pedersen, Jon Spangenberg, A numerical investigation of the inter-layer bond and surface roughness during the yield stress buildup in wet-on-wet material extrusion additive manufacturing, ASPE and euspen Summer Topical Meeting, 77, 2022.

    182-22   Chan Kyu Kim, Dae-Won Cho, Seok Kim, Sang Woo Song, Kang Myung Seo, Young Tae Cho, High-throughput metal 3D printing pen enabled by a continuous molten droplet transfer, Advanced Science, 2205085, 2022. doi.org/10.1002/advs.202205085

    180-22 Xu Kaikai, Gong Yadong, Zhang Qiang, Numerical simulation of dynamic analysis of molten pool in the process of direct energy deposition, The International Journal of Advanced Manufacturing Technology, 2022. doi.org/10.1007/s00170-022-10271-7

    179-22 Yasuhiro Okamoto, Nozomi Taura, Akira Okada, Study on laser drilling process of solid metal on its liquid, International Journal of Electrical Machining, 27; 2022. doi.org/10.2526/ijem.27.35

    175-22 Lu Min, Xhi Xiaojie, Lu Peipei, Wu Meiping, Forming quality and wettability of surface texture on CuSn10 fabricated by laser powder bed fusion, AIP Advances, 12.12; 125114, 2022. doi.org/10.1063/5.0122076

    174-22 Thinus Van Rhijn, Willie Du Preez, Maina Maringa, Dean Kouprianoff, An investigation into the optimization of the selective laser melting process parameters for Ti6Al4V through numerical modelling, JOM, 2022. doi.org/10.1007/s11837-022-05608-2

    171-22 Jonathan Yoshioka, Mohsen Eshraghi, Temporal evolution of temperature gradient and solidification rate in laser powder bed fusion additive manufacturing, Heat and Mass Transfer, 2022. doi.org/10.1007/s00231-022-03318-8

    170-22 Subin Shrestha and Kevin Chou, Residual heat effect on the melt pool geometry during the laser powder bed fusion process, Journal of Manufacturing and Materials Processing, 6.6; 153, 2022. doi.org/10.3390/jmmp6060153

    169-22 Aryan Aryan, Obinna Chukwubuzo, Desmond Bourgeois, Wei Zhang, Hardness prediction by incorporating heat transfer and molten pool fluid flow in a mult-pass, multi-layer weld for onsite repair of Grade 91 steel, U.S. Department of Energy Office of Scientific and Technical Information, DOE-OSU-0032067, 2022. doi.org/10.2172/1898594

    158-22 Dafan Du, Lu Wang, Anping Dong, Wentao Yan, Guoliang Zhu, Baode Sun, Promoting the densification and grain refinement with assistance of static magnetic field in laser powder bed fusion, International Journal of Machine Tools and Manufacture, 183; 103965, 2022. doi.org/10.1016/j.ijmachtools.2022.103965

    157-22 Han Chu, Jiang Ping, Geng Shaoning, Liu Kun, Nucleation mechanism in oscillating laser welds of 2024 aluminium alloy: A combined experimental and numerical study, Optics & Laser Technology, 158.A; 108812, 2022. doi.org/10.1016/j.optlastec.2022.108812

    153-22 Zixiang Li, Yinan Cui, Baohua Chang, Guan Liu, Ze Pu, Haoyu Zhang, Zhiyue Liang, Changmeng Liu, Li Wang, Dong Du, Manipulating molten pool in in-situ additive manufacturing of Ti-22Al-25 Nb through alternating dual-electron beams, Additive Manufacturing, 60.A; 103230, 2022. doi.org/10.1016/j.addma.2022.103230

    149-22   Qian Chen, Yao Fu, Albert C. To, Multiphysics modeling of particle spattering and induced defect formation mechanism in Inconel 718 laser powder bed fusion, The International Journal of Advanced Manufacturing Technology, 123; pp. 783-791, 2022. doi.org/10.1007/s00170-022-10201-7

    146-22   Zixuan Wan, Hui-ping Wang, Jingjing Li, Baixuan Yang, Joshua Solomon, Blair Carlson, Effect of welding mode on remote laser stitch welding of zinc-coated steel with different sheet thickness combinations, Journal of Manufacturing Science and Engineering, MANU-21-1598, 2022. doi.org/10.1115/1.4055792

    143-22   Du-Rim Eo, Seong-Gyu Chung, JeongHo Yang, Won Tae Cho, Sun-Hong Park, Jung-Wook Cho, Surface modification of high-Mn steel via laser-DED: Microstructural characterization and hot crack susceptibility of clad layer, Materials & Design, 223; 111188, 2022. doi.org/10.1016/j.matdes.2022.111188

    142-22   Zichuan Fu, Xiangman Zhou, Bin Luo, Qihua Tian, Numerical simulation study of the effect of weld current on WAAM welding pool dynamic and weld bead morphology, International Conference on Mechanical Design and Simulation, Proceedings, 12261; 122614G, 2022. doi.org/10.1117/12.2639074

    132-22   Yiyu Huang, Zhonghao Xie, Wenshu Li, Haoyu Chen, Bin Liu, Bingfeng Wang, Dynamic mechanical properties of the selective laser melting NiCrFeCoMo0.2 high entropy alloy and the microstructure of molten pool, Journal of Alloys and Compounds, 927; 167011, 2022. doi.org/10.1016/j.jallcom.2022.167011

    126-22   Jingqi Zhang, Yingang Liu, Gang Sha, Shenbao Jin, Ziyong Hou, Mohamad Bayat, Nan Yang, Qiyang Tan, Yu Yin, Shiyang Liu, Jesper Henri Hattel, Matthew Dargusch, Xiaoxu Huang, Ming-Xing Zhang, Designing against phase and property heterogeneities in additively manufactured titanium alloys, Nature Communications, 13; 4660, 2022. doi.org/10.1038/s41467-022-32446-2

    119-22   Xu Kaikai, Gong Yadong, Zhao Qiang, Numerical simulation on molten pool flow of Inconel718 alloy based on VOF during additive manufacturing, Materials Today Communications, 33; 104147, 2022. doi.org/10.1016/j.mtcomm.2022.104147

    118-22   AmirPouya Hemmasian, Francis Ogoke, Parand Akbari, Jonathan Malen, Jack Beuth, Amir Barati Farimani, Surrogate modeling of melt pool thermal field using deep learning, SSRN, 2022. doi.org/10.2139/ssrn.4190835

    117-22   Chiara Ransenigo, Marialaura Tocci, Filippo Palo, Paola Ginestra, Elisabetta Ceretti, Marcello Gelfi, Annalisa Pola, Evolution of melt pool and porosity during laser powder bed fusion of Ti6Al4V alloy: Numerical modelling and experimental validation, Lasers in Manufacturing and Materials Processing, 2022. doi.org/10.1007/s40516-022-00185-3

    112-22   Chris Jasien, Alec Saville, Chandler Gus Becker, Jonah Klemm-Toole, Kamel Fezzaa, Tao Sun, Tresa Pollock, Amy J. Clarke, In situ x-ray radiography and computational modeling to predict grain morphology in β-titanium during simulated additive manufacturing, Metals, 12.7; 1217, 2022. doi.org/10.3390/met12071217

    110-22   Haotian Zhou, Haijun Su, Yinuo Guo, Peixin Yang, Yuan Liu, Zhonglin Shen, Di Zhao, Haifang Liu, Taiwen Huang, Min Guo, Jun Zhang, Lin Liu, Hengzhi Fu, Formation and evolution mechanisms of pores in Inconel 718 during selective laser melting: Meso-scale modeling and experimental investigations, Journal of Manufacturing Processes, 81; pp. 202-213, 2022. doi.org/10.1016/j.jmapro.2022.06.072

    109-22   Yufan Zhao, Huakang Bian, Hao Wang, Aoyagi Kenta, Yamanaka Kenta, Akihiko Chiba, Non-equilibrium solidification behavior associated with powder characteristics during electron beam additive manufacturing, Materials & Design, 221; 110915, 2022. doi.org/10.1016/j.matdes.2022.110915

    107-22   Dan Lönn, David Spångberg, Study of process parameters in laser beam welding of copper hairpins, Thesis, University of Skövde, 2022.

    106-22   Liping Guo, Hongze Wang, Qianglong Wei, Hanjie Liu, An Wang, Yi Wu, Haowei Wang, A comprehensive model to quantify the effects of additional nano-particles on the printability in laser powder bed fusion of aluminum alloy and composite, Additive Manufacturing, 58; 103011, 2022. doi.org/10.1016/j.addma.2022.103011

    104-22   Hongjiang Pan, Thomas Dahmen, Mohamad Bayat, Kang Lin, Xiaodan Zhang, Independent effects of laser power and scanning speed on IN718’s precipitation and mechanical properties produced by LBPF plus heat treatment, Materials Science and Engineering: A, 849; 143530, 2022. doi.org/10.1016/j.msea.2022.143530

    101-22   Yufan Zhao, Kenta Aoyagi, Kenta Yamanaka, Akihiko Chiba, A survey on basic influencing factors of solidified grain morphology during electron beam melting, Materials & Design, 221; 110927, 2022. doi.org/10.1016/j.matdes.2022.110927

    98-22   Jon Spangenberg, Wilson Ricardo Leal da Silva, Md. Tusher Mollah, Raphaël Comminal, Thomas Juul Andersen, Henrik Stang, Integrating reinforcement with 3D concrete printing: Experiments and numerical modelling, Third RILEM International Conference on Concrete and Digital Fabrication, Eds. Ana Blanco, Peter Kinnell, Richard Buswell, Sergio Cavalaro, pp. 379-384, 2022.

    93-22   Minglei Qu, Qilin Guo, Luis I. Escano, Samuel J. Clark Kamel Fezzaa, Lianyi Chen, Mitigating keyhole pore formation by nanoparticles during laser powder bed fusion additive manufacturing, Additive Manufacturing Letters, 100068, 2022. doi.org/10.1016/j.addlet.2022.100068

    86-22   Patiparn Ninpetch, Prasert Chalermkarnnon, Pruet Kowitwarangkul, Multiphysics simulation of thermal-fluid behavior in laser powder bed fusion of H13 steel: Influence of layer thickness and energy input, Metals and Materials International, 2022. doi.org/10.1007/s12540-022-01239-z

    85-22   Merve Biyikli, Taner Karagoz, Metin Calli, Talha Muslim, A. Alper Ozalp, Ali Bayram, Single track geometry prediction of laser metal deposited 316L-Si via multi-physics modelling and regression analysis with experimental validation, Metals and Materials International, 2022. doi.org/10.1007/s12540-022-01243-3

    76-22   Zhichao Yang, Shuhao Wang, Lida Zhu, Jinsheng Ning, Bo Xin, Yichao Dun, Wentao Yan, Manipulating molten pool dynamics during metal 3D printing by ultrasound, Applied Physics Reviews, 9; 021416, 2022. doi.org/10.1063/5.0082461

    73-22   Yu Sun, Liqun Li, Yu Hao, Sanbao Lin, Xinhua Tang, Fenggui Lu, Numerical modeling on formation of periodic chain-like pores in high power laser welding of thick steel plate, Journal of Materials Processing Technology, 306; 117638, 2022. doi.org/10.1016/j.jmatprotec.2022.117638

    67-22   Yu Hao, Hiu-Ping Wang, Yu Sun, Liqun Li, Yihan Wu, Fenggui Lu, The evaporation behavior of zince and its effect on spattering in laser overlap welding of galvanized steels, Journal of Materials Processing Technology, 306; 117625, 2022. doi.org/10.1016/j.jmatprotec.2022.117625

    65-22   Yanhua Zhao, Chuanbin Du, Peifu Wang, Wei Meng, Changming Li, The mechanism of in-situ laser polishing and its effect on the surface quality of nickel-based alloy fabricated by selective laser melting, Metals, 12.5; 778, 2022. doi.org/10.3390/met12050778

    58-22   W.E. Alphonso, M. Bayat, M. Baier, S. Carmignato, J.H. Hattel, Multi-physics numerical modelling of 316L Austenitic stainless steel in laser powder bed fusion process at meso-scale, 17th UK Heat Transfer Conference (UKHTC2021), Manchester, UK, April 4-6, 2022.

    57-22   Brandon Hayes, Travis Hainsworth, Robert MacCurdy, Liquid-solid co-printing of multi-material 3D fluidic devices via material jetting, Additive Manufacturing, in press, 102785, 2022. doi.org/10.1016/j.addma.2022.102785

    55-22   Xiang Wang, Lin-Jie Zhang, Jie Ning, Suck-joo Na, Fluid thermodynamic simulation of Ti-6Al-4V alloy in laser wire deposition, 3D Printing and Additive Manufacturing, 2022. doi.org/10.1089/3dp.2021.0159

    54-22   Junhao Zhao, Binbin Wang, Tong Liu, Liangshu Luo, Yanan Wang, Xiaonan Zheng, Liang Wang, Yanqing Su, Jingjie Guo, Hengzhi Fu, Dayong Chen, Study of in situ formed quasicrystals in Al-Mn based alloys fabricated by SLM, Journal of Alloys and Compounds, 909; 164847, 2022. doi.org/10.1016/j.jallcom.2022.164847

    48-22   Yueming Sun, Jianxing Ma, Fei Peng, Konstantin G. Kornev, Making droplets from highly viscous liquids by pushing a wire through a tube, Physics of Fluids, 34; 032119, 2022. doi.org/10.1063/5.0082003

    46-22   H.Z. Lu, T. Chen, H. Liu, H. Wang, X. Luo, C.H. Song, Constructing function domains in NiTi shape memory alloys by additive manufacturing, Virtual and Physical Prototyping, 17.3; 2022. doi.org/10.1080/17452759.2022.2053821

    42-22   Islam Hassan, P. Ravi Selvaganapathy, Microfluidic printheads for highly switchable multimaterial 3D printing of soft materials, Advanced Materials Technologies, 2101709, 2022. doi.org/10.1002/admt.202101709

    41-22   Nan Yang, Youping Gong, Honghao Chen, Wenxin Li, Chuanping Zhou, Rougang Zhou, Huifeng Shao, Personalized artificial tibia bone structure design and processing based on laser powder bed fusion, Machines, 10.3; 205, 2022. doi.org/10.3390/machines10030205

    31-22   Bo Shen, Raghav Gnanasambandam, Rongxuan Wang, Zhenyu (James) Kong, Multi-Task Gaussian process upper confidence bound for hyperparameter tuning and its application for simulation studies of additive manufacturing, IISE Transactions, 2022. doi.org/10.1080/24725854.2022.2039813

    27-22   Lida Zhu, Shuhao Wang, Hao Lu, Dongxing Qi, Dan Wang, Zhichao Yang, Investigation on synergism between additive and subtractive manufacturing for curved thin-walled structure, Virtual and Physical Prototyping, 17.2; 2022. doi.org/10.1080/17452759.2022.2029009

    24-22   Hoon Sohn, Peipei Liu, Hansol Yoon, Kiyoon Yi, Liu Yang, Sangjun Kim, Real-time porosity reduction during metal directed energy deposition using a pulse laser, Journal of Materials Science & Technology, 116; pp. 214-223. doi.org/10.1016/j.jmst.2021.12.013

    18-22   Yaohong Xiao, Zixuan Wan, Pengwei Liu, Zhuo Wang, Jingjing Li, Lei Chen, Quantitative simulations of grain nucleation and growth at additively manufactured bimetallic interfaces of SS316L and IN625, Journal of Materials Processing Technology, 302; 117506, 2022. doi.org/10.1016/j.jmatprotec.2022.117506

    06-22   Amal Charles, Mohamad Bayat, Ahmed Elkaseer, Lore Thijs, Jesper Henri Hattel, Steffen Scholz, Elucidation of dross formation in laser powder bed fusion at down-facing surfaces: Phenomenon-oriented multiphysics simulation and experimental validation, Additive Manufacturing, 50; 102551, 2022. doi.org/10.1016/j.addma.2021.102551

    05-22   Feilong Ji, Xunpeng Qin, Zeqi Hu, Xiaochen Xiong, Mao Ni, Mengwu Wu, Influence of ultrasonic vibration on molten pool behavior and deposition layer forming morphology for wire and arc additive manufacturing, International Communications in Heat and Mass Transfer, 130; 105789, 2022. doi.org/10.1016/j.icheatmasstransfer.2021.105789

    150-21   Daniel Knüttel, Stefano Baraldo, Anna Valente, Konrad Wegener, Emanuele Carpanzano, Model based learning for efficient modelling of heat transfer dynamics, Procedia CIRP, 102; pp. 252-257, 2021. doi.org/10.1016/j.procir.2021.09.043

    149-21   T. van Rhijn, W. du Preez, M. Maringa, D. Kouprianoff, Towards predicting process parameters for selective laser melting of titanium alloys through the modelling of melt pool characteristics, Suid-Afrikaanse Tydskrif vir Natuurwetenskap en Tegnologie, 40.1; 2021. 

    148-21   Qian Chen, Multiscale process modeling of residual deformation and defect formation for laser powder bed fusion additive manufacturing, Thesis, University of Pittsburgh, Pittsburgh, PA USA, 2021. 

    147-21   Pareekshith Allu, Developing process parameters through CFD simulations, Lasers in Manufacturing Conference, 2021.

    143-21   Asif Ur Rehman, Muhammad Arif Mahmood, Fatih Pitir, Metin Uymaz Salamci, Andrei C. Popescu, Ion N. Mihailescu, Spatter formation and splashing induced defects in laser-based powder bed fusion of AlSi10Mg alloy: A novel hydrodynamics modelling with empirical testing, Metals, 11.12; 2023, 2021. doi.org/10.3390/met11122023

    142-21   Islam Hassan, Ponnambalam Ravi Selvaganapathy, A microfluidic printhead with integrated hybrid mixing by sequential injection for multimaterial 3D printing, Additive Manufacturing, 102559, 2021. doi.org/10.1016/j.addma.2021.102559

    137-21   Ting-Yu Cheng, Ying-Chih Liao, Enhancing drop mixing in powder bed by alternative particle arrangements with contradictory hydrophilicity, Journal of the Taiwan Institute of Chemical Engineers, 104160, 2021. doi.org/10.1016/j.jtice.2021.104160

    134-21   Asif Ur Rehman, Muhammad Arif Mahmood, Fatih Pitir, Metin Uymaz Salamci, Andrei C. Popescu, Ion N. Mihailescu, Keyhole formation by laser drilling in laser powder bed fusion of Ti6Al4V biomedical alloy: Mesoscopic computational fluid dynamics simulation versus mathematical modelling using empirical validation, Nanomaterials, 11.2; 3284, 2021. doi.org/10.3390/nano11123284

    128-21   Sang-Woo Han, Won-Ik Cho, Lin-Jie Zhang, Suck-Joo Na, Coupled simulation of thermal-metallurgical-mechanical behavior in laser keyhole welding of AH36 steel, Materials & Design, 212; 110275, 2021. doi.org/10.1016/j.matdes.2021.110275

    127-21   Jiankang Huang, Zhuoxuan Li, Shurong Yu, Xiaoquan Yu, Ding Fan, Real-time observation and numerical simulation of the molten pool flow and mass transfer behavior during wire arc additive manufacturing, Welding in the World, 2021. doi.org/10.1007/s40194-021-01214-z

    123-21   Boxue Song, Tianbiao Yu, Xingyu Jiang, Wenchao Xi, Xiaoli Lin, Zhelun Ma, ZhaoWang, Development of the molten pool and solidification characterization in single bead multilayer direct energy deposition, Additive Manufacturing, 102479, 2021. doi.org/10.1016/j.addma.2021.102479

    112-21   Kathryn Small, Ian D. McCue, Katrina Johnston, Ian Donaldson, Mitra L. Taheri, Precision modification of microstructure and properties through laser engraving, JOM, 2021. doi.org/10.1007/s11837-021-04959-6

    111-21   Yongki Lee, Jason Cheon, Byung-Kwon Min, Cheolhee Kim, Modelling of fume particle behaviour and coupling glass contamination during vacuum laser beam welding, Science and Technology of Welding and Joining, 2021. doi.org/10.1080/13621718.2021.1990658

    110-21   Menglin Liu, Hao Yi, Huajun Cao, Rufeng Huang, Le Jia, Heat accumulation effect in metal droplet-based 3D printing: Evolution mechanism and elimination strategy, Additive Manufacturing, 48.A; 102413, 2021. doi.org/10.1016/j.addma.2021.102413

    108-21   Nozomi Taura, Akiya Mitsunobu, Tatsuhiko Sakai, Yasuhiro Okamoto, Akira Okada, Formation and its mechanism of high-speed micro-grooving on metal surface by angled CW laser irradiation, Journal of Laser Micro/Nanoengineering, 16.2, 2021. doi.org/10.2961/jlmn.2021.02.2006

    105-21   Jon Spangenberg, Wilson Ricardo Leal da Silva, Raphaël Comminal, Md. Tusher Mollah, Thomas Juul Andersen, Henrik Stang, Numerical simulation of multi-layer 3D concrete printing, RILEM Technical Letters, 6; pp. 119-123, 2021. doi.org/10.21809/rilemtechlett.2021.142

    104-21   Lin Chen, Chunming Wang, Gaoyang Mi, Xiong Zhang, Effects of laser oscillating frequency on energy distribution, molten pool morphology and grain structure of AA6061/AA5182 aluminum alloys lap welding, Journal of Materials Research and Technology, 15; pp. 3133-3148, 2021. doi.org/10.1016/j.jmrt.2021.09.141

    101-21   R.J.M. Wolfs, T.A.M. Salet, N. Roussel, Filament geometry control in extrusion-based additive manufacturing of concrete: The good, the bad and the ugly, Cement and Concrete Research, 150; 106615, 2021. doi.org/10.1016/j.cemconres.2021.106615

    89-21   Wenlin Ye, Jin Bao, Jie Lei, Yichang Huang, Zhihao Li, Peisheng Li, Ying Zhang, Multiphysics modeling of thermal behavior of commercial pure titanium powder during selective laser melting, Metals and Materials International, 2021. doi.org/10.1007/s12540-021-01019-1

    81-21   Lin Chen, Gaoyang Mi, Xiong Zhang, Chunming Wang, Effects of sinusoidal oscillating laser beam on weld formation, melt flow and grain structure during aluminum alloys lap welding, Journals of Materials Processing Technology, 298; 117314, 2021. doi.org/10.1016/j.jmatprotec.2021.117314

    77-21   Yujie Cui, Yufan Zhao, Haruko Numata, Kenta Yamanaka, Huakang Bian, Kenta Aoyagi, Akihiko Chiba, Effects of process parameters and cooling gas on powder formation during the plasma rotating electrode process, Powder Technology, 393; pp. 301-311, 2021. doi.org/10.1016/j.powtec.2021.07.062

    76-21   Md Tusher Mollah, Raphaël Comminal, Marcin P. Serdeczny, David B. Pedersen, Jon Spangenberg, Stability and deformations of deposited layers in material extrusion additive manufacturing, Additive Manufacturing, 46; 102193, 2021. doi.org/10.1016/j.addma.2021.102193

    72-21   S. Sabooni, A. Chabok, S.C. Feng, H. Blaauw, T.C. Pijper, H.J. Yang, Y.T. Pei, Laser powder bed fusion of 17–4 PH stainless steel: A comparative study on the effect of heat treatment on the microstructure evolution and mechanical properties, Additive Manufacturing, 46; 102176, 2021. doi.org/10.1016/j.addma.2021.102176

    71-21   Yu Hao, Nannan Chena, Hui-Ping Wang, Blair E. Carlson, Fenggui Lu, Effect of zinc vapor forces on spattering in partial penetration laser welding of zinc-coated steels, Journal of Materials Processing Technology, 298; 117282, 2021. doi.org/10.1016/j.jmatprotec.2021.117282

    67-21   Lu Wang, Wentao Yan, Thermoelectric magnetohydrodynamic model for laser-based metal additive manufacturing, Physical Review Applied, 15.6; 064051, 2021. doi.org/10.1103/PhysRevApplied.15.064051

    61-21   Ian D. McCue, Gianna M. Valentino, Douglas B. Trigg, Andrew M. Lennon, Chuck E. Hebert, Drew P. Seker, Salahudin M. Nimer, James P. Mastrandrea, Morgana M. Trexler, Steven M. Storck, Controlled shape-morphing metallic components for deployable structures, Materials & Design, 208; 109935, 2021. doi.org/10.1016/j.matdes.2021.109935

    60-21   Mahyar Khorasani, AmirHossein Ghasemi, Martin Leary, William O’Neil, Ian Gibson, Laura Cordova, Bernard Rolfe, Numerical and analytical investigation on meltpool temperature of laser-based powder bed fusion of IN718, International Journal of Heat and Mass Transfer, 177; 121477, 2021. doi.org/10.1016/j.ijheatmasstransfer.2021.121477

    57-21   Dae-Won Cho, Yeong-Do Park, Muralimohan Cheepu, Numerical simulation of slag movement from Marangoni flow for GMAW with computational fluid dynamics, International Communications in Heat and Mass Transfer, 125; 105243, 2021. doi.org/10.1016/j.icheatmasstransfer.2021.105243

    55-21   Won-Sang Shin, Dae-Won Cho, Donghyuck Jung, Heeshin Kang, Jeng O Kim, Yoon-Jun Kim, Changkyoo Park, Investigation on laser welding of Al ribbon to Cu sheet: Weldability, microstructure and mechanical and electrical properties, Metals, 11.5; 831, 2021. doi.org/10.3390/met11050831

    50-21   Mohamad Bayat, Venkata K. Nadimpalli, Francesco G. Biondani, Sina Jafarzadeh, Jesper Thorborg, Niels S. Tiedje, Giuliano Bissacco, David B. Pedersen, Jesper H. Hattel, On the role of the powder stream on the heat and fluid flow conditions during directed energy deposition of maraging steel—Multiphysics modeling and experimental validation, Additive Manufacturing, 43;102021, 2021. doi.org/10.1016/j.addma.2021.102021

    47-21   Subin Shrestha, Kevin Chou, An investigation into melting modes in selective laser melting of Inconel 625 powder: single track geometry and porosity, The International Journal of Advanced Manufacturing Technology, 2021. doi.org/10.1007/s00170-021-07105-3

    34-21   Haokun Sun, Xin Chu, Cheng Luo, Haoxiu Chen, Zhiying Liu, Yansong Zhang, Yu Zou, Selective laser melting for joining dissimilar materials: Investigations ofiInterfacial characteristics and in situ alloying, Metallurgical and Materials Transactions A, 52; pp. 1540-1550, 2021. doi.org/10.1007/s11661-021-06178-9

    32-21   Shanshan Zhang, Subin Shrestha, Kevin Chou, On mesoscopic surface formation in metal laser powder-bed fusion process, Supplimental Proceedings, TMS 150th Annual Meeting & Exhibition (Virtual), pp. 149-161, 2021. doi.org/10.1007/978-3-030-65261-6_14

    22-21   Patiparn Ninpetch, Pruet Kowitwarangkul, Sitthipong Mahathanabodee, Prasert Chalermkarnnon, Phadungsak Rattanadecho, Computational investigation of thermal behavior and molten metal flow with moving laser heat source for selective laser melting process, Case Studies in Thermal Engineering, 24; 100860, 2021. doi.org/10.1016/j.csite.2021.100860

    19-21   M.B. Abrami, C. Ransenigo, M. Tocci, A. Pola, M. Obeidi, D. Brabazon, Numerical simulation of laser powder bed fusion processes, La Metallurgia Italiana, February; pp. 81-89, 2021.

    16-21   Wenjun Ge, Jerry Y.H. Fuh, Suck Joo Na, Numerical modelling of keyhole formation in selective laser melting of Ti6Al4V, Journal of Manufacturing Processes, 62; pp. 646-654, 2021. doi.org/10.1016/j.jmapro.2021.01.005

    11-21   Mohamad Bayat, Venkata K. Nadimpalli, David B. Pedersen, Jesper H. Hattel, A fundamental investigation of thermo-capillarity in laser powder bed fusion of metals and alloys, International Journal of Heat and Mass Transfer, 166; 120766, 2021. doi.org/10.1016/j.ijheatmasstransfer.2020.120766

    10-21   Yufan Zhao, Yuichiro Koizumi, Kenta Aoyagi, Kenta Yamanaka, Akihiko Chiba, Thermal properties of powder beds in energy absorption and heat transfer during additive manufacturing with electron beam, Powder Technology, 381; pp. 44-54, 2021. doi.org/10.1016/j.powtec.2020.11.082

    9-21   Subin Shrestha, Kevin Chou, A study of transient and steady-state regions from single-track deposition in laser powder bed fusion, Journal of Manufacturing Processes, 61; pp. 226-235, 2021. doi.org/10.1016/j.jmapro.2020.11.023

    6-21   Qian Chen, Yunhao Zhao, Seth Strayer, Yufan Zhao, Kenta Aoyagi, Yuichiro Koizumi, Akihiko Chiba, Wei Xiong, Albert C. To, Elucidating the effect of preheating temperature on melt pool morphology variation in Inconel 718 laser powder bed fusion via simulation and experiment, Additive Manufacturing, 37; 101642, 2021. doi.org/10.1016/j.addma.2020.101642

    04-21   Won-Ik Cho, Peer Woizeschke, Analysis of molten pool dynamics in laser welding with beam oscillation and filler wire feeding, International Journal of Heat and Mass Transfer, 164; 120623, 2021. doi.org/10.1016/j.ijheatmasstransfer.2020.120623

    128-20   Mahmood Al Bashir, Rajeev Nair, Martina M. Sanchez, Anil Mahapatro, Improving fluid retention properties of 316L stainless steel using nanosecond pulsed laser surface texturing, Journal of Laser Applications, 32.4, 2020. doi.org/10.2351/7.0000199

    127-20   Eric Riedel, Niklas Bergedieck, Stefan Scharf, CFD simulation based investigation of cavitation cynamics during high intensity ultrasonic treatment of A356, Metals, 10.11; 1529, 2020. doi.org/10.3390/met10111529

    126-20   Benjamin Himmel, Material jetting of aluminium: Analysis of a novel additive manufacturing process, Thesis, Technical University of Munich, Munich, Germany, 2020. 

    121-20   Yufan Zhao, Yujie Cui, Haruko Numata, Huakang Bian, Kimio Wako, Kenta Yamanaka, Kenta Aoyagi, Akihiko Chiba, Centrifugal granulation behavior in metallic powder fabrication by plasma rotating electrode process, Scientific Reports, 10; 18446, 2020. doi.org/10.1038/s41598-020-75503-w

    116-20   Raphael Comminal, Wilson Ricardo Leal da Silva, Thomas Juul Andersen, Henrik Stang, Jon Spangenberg, Modelling of 3D concrete printing based on computational fluid dynamics, Cement and Concrete Research, 138; 106256, 2020. doi.org/10.1016/j.cemconres.2020.106256

    112-20   Peng Liu, Lijin Huan, Yu Gan, Yuyu Lei, Effect of plate thickness on weld pool dynamics and keyhole-induced porosity formation in laser welding of Al alloy, The International Journal of Advanced Manufacturing Technology, 111; pp. 735-747, 2020. doi.org/10.1007/s00170-020-05818-5

    108-20   Fan Chen, Wentao Yan, High-fidelity modelling of thermal stress for additive manufacturing by linking thermal-fluid and mechanical models, Materials & Design, 196; 109185, 2020. doi.org/10.1016/j.matdes.2020.109185

    104-20   Yunfu Tian, Lijun Yang, Dejin Zhao, Yiming Huang, Jiajing Pan, Numerical analysis of powder bed generation and single track forming for selective laser melting of SS316L stainless steel, Journal of Manufacturing Processes, 58; pp. 964-974, 2020. doi.org/10.1016/j.jmapro.2020.09.002

    100-20   Raphaël Comminal, Sina Jafarzadeh, Marcin Serdeczny, Jon Spangenberg, Estimations of interlayer contacts in extrusion additive manufacturing using a CFD model, International Conference on Additive Manufacturing in Products and Applications (AMPA), Zurich, Switzerland, September 1-3: Industrializing Additive Manufacturing, pp. 241-250, 2020. doi.org/10.1007/978-3-030-54334-1_17

    97-20   Paree Allu, CFD simulation for metal Additive Manufacturing: Applications in laser- and sinter-based processes, Metal AM, 6.4; pp. 151-158, 2020.

    95-20   Yufan Zhao, Kenta Aoyagi, Kenta Yamanaka, Akihiko Chiba, Role of operating and environmental conditions in determining molten pool dynamics during electron beam melting and selective laser melting, Additive Manufacturing, 36; 101559, 2020. doi.org/10.1016/j.addma.2020.101559

    94-20   Yan Zeng, David Himmler, Peter Randelzhofer, Carolin Körner, Processing of in situ Al3Ti/Al composites by advanced high shear technology: influence of mixing speed, The International Journal of Advanced Manufacturing Technology, 110; pp. 1589-1599, 2020. doi.org/10.1007/s00170-020-05956-w

    93-20   H. Hamed Zargari, K. Ito, M. Kumar, A. Sharma, Visualizing the vibration effect on the tandem-pulsed gas metal arc welding in the presence of surface tension active elements, International Journal of Heat and Mass Transfer, 161; 120310, 2020. doi.org/10.1016/j.ijheatmasstransfer.2020.120310

    90-20   Guangxi Zhao, Jun Du, Zhengying Wei, Siyuan Xu, Ruwei Geng, Numerical analysis of aluminum alloy fused coating process, Journal of the Brazilian Society of Mechanical Science and Engineering, 42; 483, 2020. doi.org/10.1007/s40430-020-02569-y

    85-20   Wenkang Huang, Hongliang Wang, Teresa Rinker, Wenda Tan, Investigation of metal mixing in laser keyhold welding of dissimilar metals, Materials & Design, 195; 109056, 2020. doi.org/10.1016/j.matdes.2020.109056

    82-20   Pan Lu, Zhang Cheng-Lin, Wang Liang, Liu Tong, Liu Jiang-lin, Molten pool structure, temperature and velocity flow in selective laser melting AlCu5MnCdVA alloy, Materials Research Express, 7; 086516, 2020. doi.org/10.1088/2053-1591/abadcf

    80-20   Yujie Cui, Yufan Zhao, Haruko Numata, Huakang Bian, Kimio Wako, Kento Yamanaka, Kenta Aoyagi, Chen Zhang, Akihiko Chiba, Effects of plasma rotating electrode process parameters on the particle size distribution and microstructure of Ti-6Al-4 V alloy powder, Powder Technology, 376; pp. 363-372, 2020. doi.org/10.1016/j.powtec.2020.08.027

    78-20   F.Q. Liu, L. Wei, S.Q. Shi, H.L. Wei, On the varieties of build features during multi-layer laser directed energy deposition, Additive Manufacturing, 36; 101491, 2020. doi.org/10.1016/j.addma.2020.101491

    75-20   Nannan Chen, Zixuan Wan, Hui-Ping Wang, Jingjing Li, Joshua Solomon, Blair E. Carlson, Effect of Al single bond Si coating on laser spot welding of press hardened steel and process improvement with annular stirring, Materials & Design, 195; 108986, 2020. doi.org/10.1016/j.matdes.2020.108986

    72-20   Yujie Cui, Kenta Aoyagi, Yufan Zhao, Kenta Yamanaka, Yuichiro Hayasaka, Yuichiro Koizumi, Tadashi Fujieda, Akihiko Chiba, Manufacturing of a nanosized TiB strengthened Ti-based alloy via electron beam powder bed fusion, Additive Manufacturing, 36; 101472, 2020. doi.org/10.1016/j.addma.2020.101472

    64-20   Dong-Rong Liu, Shuhao Wang, Wentao Yan, Grain structure evolution in transition-mode melting in direct energy deposition, Materials & Design, 194; 108919, 2020. doi.org/10.1016/j.matdes.2020.108919

    61-20   Raphael Comminal, Wilson Ricardo Leal da Silva, Thomas Juul Andersen, Henrik Stang, Jon Spangenberg, Influence of processing parameters on the layer geometry in 3D concrete printing: Experiments and modelling, 2nd RILEM International Conference on Concrete and Digital Fabrication, RILEM Bookseries, 28; pp. 852-862, 2020. doi.org/10.1007/978-3-030-49916-7_83

    60-20   Marcin P. Serdeczny, Raphaël Comminal, Md. Tusher Mollah, David B. Pedersen, Jon Spangenberg, Numerical modeling of the polymer flow through the hot-end in filament-based material extrusion additive manufacturing, Additive Manufacturing, 36; 101454, 2020. doi.org/10.1016/j.addma.2020.101454

    58-20   H.L. Wei, T. Mukherjee, W. Zhang, J.S. Zuback, G.L. Knapp, A. De, T. DebRoy, Mechanistic models for additive manufacturing of metallic components, Progress in Materials Science, 116; 100703, 2020. doi.org/10.1016/j.pmatsci.2020.100703

    55-20   Masoud Mohammadpour, Experimental study and numerical simulation of heat transfer and fluid flow in laser welded and brazed joints, Thesis, Southern Methodist University, Dallas, TX, US; Available in Mechanical Engineering Research Theses and Dissertations, 24, 2020.

    48-20   Masoud Mohammadpour, Baixuan Yang, Hui-Ping Wang, John Forrest, Michael Poss, Blair Carlson, Radovan Kovacevica, Influence of laser beam inclination angle on galvanized steel laser braze quality, Optics and Laser Technology, 129; 106303, 2020. doi.org/10.1016/j.optlastec.2020.106303

    34-20   Binqi Liu, Gang Fang, Liping Lei, Wei Liu, A new ray tracing heat source model for mesoscale CFD simulation of selective laser melting (SLM), Applied Mathematical Modeling, 79; pp. 506-520, 2020. doi.org/10.1016/j.apm.2019.10.049

    27-20   Xuesong Gao, Guilherme Abreu Farira, Wei Zhang and Kevin Wheeler, Numerical analysis of non-spherical particle effect on molten pool dynamics in laser-powder bed fusion additive manufacturing, Computational Materials Science, 179, art. no. 109648, 2020. doi.org/10.1016/j.commatsci.2020.109648

    26-20   Yufan Zhao, Yuichiro Koizumi, Kenta Aoyagi, Kenta Yamanaka and Akihiko Chiba, Isothermal γ → ε phase transformation behavior in a Co-Cr-Mo alloy depending on thermal history during electron beam powder-bed additive manufacturing, Journal of Materials Science & Technology, 50, pp. 162-170, 2020. doi.org/10.1016/j.jmst.2019.11.040

    21-20   Won-Ik Cho and Peer Woizeschke, Analysis of molten pool behavior with buttonhole formation in laser keyhole welding of sheet metal, International Journal of Heat and Mass Transfer, 152, art. no. 119528, 2020. doi.org/10.1016/j.ijheatmasstransfer.2020.119528

    06-20  Wei Xing, Di Ouyang, Zhen Chen and Lin Liu, Effect of energy density on defect evolution in 3D printed Zr-based metallic glasses by selective laser melting, Science China Physics, Mechanics & Astronomy, 63, art. no. 226111, 2020. doi.org/10.1007/s11433-019-1485-8

    04-20   Santosh Reddy Sama, Tony Badamo, Paul Lynch and Guha Manogharan, Novel sprue designs in metal casting via 3D sand-printing, Additive Manufacturing, 25, pp. 563-578, 2019. doi.org/10.1016/j.addma.2018.12.009

    02-20   Dongsheng Wu, Shinichi Tashiro, Ziang Wu, Kazufumi Nomura, Xueming Hua, and Manabu Tanaka, Analysis of heat transfer and material flow in hybrid KPAW-GMAW process based on the novel three dimensional CFD simulation, International Journal of Heat and Mass Transfer, 147, art. no. 118921, 2020. doi.org/10.1016/j.ijheatmasstransfer.2019.118921

    01-20   Xiang Huang, Siying Lin, Zhenxiang Bu, Xiaolong Lin, Weijin Yi, Zhihong Lin, Peiqin Xie, and Lingyun Wang, Research on nozzle and needle combination for high frequency piezostack-driven dispenser, International Journal of Adhesion and Adhesives, 96, 2020. doi.org/10.1016/j.ijadhadh.2019.102453

    88-19   Bo Cheng and Charles Tuffile, Numerical study of porosity formation with implementation of laser multiple reflection in selective laser melting, Proceedings Volume 1: Additive Manufacturing; Manufacturing Equipment and Systems; Bio and Sustainable Manufacturing, ASME 2019 14th International Manufacturing Science and Engineering Conference, Erie, Pennsylvania, USA, June 10-14, 2019. doi.org/10.1115/MSEC2019-2891

    87-19   Shuhao Wang, Lida Zhu, Jerry Ying His Fuh, Haiquan Zhang, and Wentao Yan, Multi-physics modeling and Gaussian process regression analysis of cladding track geometry for direct energy deposition, Optics and Lasers in Engineering, 127:105950, 2019. doi.org/10.1016/j.optlaseng.2019.105950

    78-19   Bo Cheng, Lukas Loeber, Hannes Willeck, Udo Hartel, and Charles Tuffile, Computational investigation of melt pool process dynamics and pore formation in laser powder bed fusion, Journal of Materials Engineering and Performance, 28:11, 6565-6578, 2019. doi.org/10.1007/s11665-019-04435-y

    77-19   David Souders, Pareekshith Allu, Anurag Chandorkar, and Ruendy Castillo, Application of computational fluid dynamics in developing process parameters for additive manufacturing, Additive Manufacturing Journal, 9th International Conference on 3D Printing and Additive Manufacturing Technologies (AM 2019), Bangalore, India, September 7-9, 2019.

    75-19   Raphaël Comminal, Marcin Piotr Serdeczny, Navid Ranjbar, Mehdi Mehrali, David Bue Pedersen, Henrik Stang, Jon Spangenberg, Modelling of material deposition in big area additive manufacturing and 3D concrete printing, Proceedings, Advancing Precision in Additive Manufacturing, Nantes, France, September 16-18, 2019.

    73-19   Baohua Chang, Zhang Yuan, Hao Cheng, Haigang Li, Dong Du 1, and Jiguo Shan, A study on the influences of welding position on the keyhole and molten pool behavior in laser welding of a titanium alloy, Metals, 9:1082, 2019. doi.org/10.3390/met9101082

    57-19     Shengjie Deng, Hui-Ping Wang, Fenggui Lu, Joshua Solomon, and Blair E. Carlson, Investigation of spatter occurrence in remote laser spiral welding of zinc-coated steels, International Journal of Heat and Mass Transfer, Vol. 140, pp. 269-280, 2019. doi.org/10.1016/j.ijheatmasstransfer.2019.06.009

    53-19     Mohamad Bayat, Aditi Thanki, Sankhya Mohanty, Ann Witvrouw, Shoufeng Yang, Jesper Thorborg, Niels Skat Tieldje, and Jesper Henri Hattel, Keyhole-induced porosities in Laser-based Powder Bed Fusion (L-PBF) of Ti6Al4V: High-fidelity modelling and experimental validation, Additive Manufacturing, Vol. 30, 2019. doi.org/10.1016/j.addma.2019.100835

    51-19     P. Ninpetch, P. Kowitwarangkul, S. Mahathanabodee, R. Tongsri, and P. Ratanadecho, Thermal and melting track simulations of laser powder bed fusion (L-PBF), International Conference on Materials Research and Innovation (ICMARI), Bangkok, Thailand, December 17-21, 2018. IOP Conference Series: Materials Science and Engineering, Vol. 526, 2019. doi.org/10.1088/1757-899X/526/1/012030

    46-19     Hongze Wang and Yu Zou, Microscale interaction between laser and metal powder in powder-bed additive manufacturing: Conduction mode versus keyhole mode, International Journal of Heat and Mass Transfer, Vol. 142, 2019. doi.org/10.1016/j.ijheatmasstransfer.2019.118473

    45-19     Yufan Zhao, Yuichiro Koizumi, Kenta Aoyagi, Kenta Yamanaka, and Akihiko Chiba, Manipulating local heat accumulation towards controlled quality and microstructure of a Co-Cr-Mo alloy in powder bed fusion with electron beam, Materials Letters, Vol. 254, pp. 269-272, 2019. doi.org/10.1016/j.matlet.2019.07.078

    44-19     Guoxiang Xu, Lin Li, Houxiao Wang, Pengfei Li, Qinghu Guo, Qingxian Hu, and Baoshuai Du, Simulation and experimental studies of keyhole induced porosity in laser-MIG hybrid fillet welding of aluminum alloy in the horizontal position, Optics & Laser Technology, Vol. 119, 2019. doi.org/10.1016/j.optlastec.2019.105667

    38-19     Subin Shrestha and Y. Kevin Chou, A numerical study on the keyhole formation during laser powder bed fusion process, Journal of Manufacturing Science and Engineering, Vol. 141, No. 10, 2019. doi.org/10.1115/1.4044100

    34-19     Dae-Won Cho, Jin-Hyeong Park, and Hyeong-Soon Moon, A study on molten pool behavior in the one pulse one drop GMAW process using computational fluid dynamics, International Journal of Heat and Mass Transfer, Vol. 139, pp. 848-859, 2019. doi.org/10.1016/j.ijheatmasstransfer.2019.05.038

    30-19     Mohamad Bayat, Sankhya Mohanty, and Jesper Henri Hattel, Multiphysics modelling of lack-of-fusion voids formation and evolution in IN718 made by multi-track/multi-layer L-PBF, International Journal of Heat and Mass Transfer, Vol. 139, pp. 95-114, 2019. doi.org/10.1016/j.ijheatmasstransfer.2019.05.003

    29-19     Yufan Zhao, Yuichiro Koizumi, Kenta Aoyagi, Daixiu Wei, Kenta Yamanaka, and Akihiko Chiba, Comprehensive study on mechanisms for grain morphology evolution and texture development in powder bed fusion with electron beam of Co–Cr–Mo alloy, Materialia, Vol. 6, 2019. doi.org/10.1016/j.mtla.2019.100346

    28-19     Pareekshith Allu, Computational fluid dynamics modeling in additive manufacturing processes, The Minerals, Metals & Materials Society (TMS) 148th Annual Meeting & Exhibition, San Antonio, Texas, USA, March 10-14, 2019.

    24-19     Simulation Software: Use, Advantages & Limitations, The Additive Manufacturing and Welding Magazine, Vol. 2, No. 2, 2019

    22-19     Hunchul Jeong, Kyungbae Park, Sungjin Baek, and Jungho Cho, Thermal efficiency decision of variable polarity aluminum arc welding through molten pool analysis, International Journal of Heat and Mass Transfer, Vol. 138, pp. 729-737, 2019. doi.org/10.1016/j.ijheatmasstransfer.2019.04.089

    07-19   Guangxi Zhao, Jun Du, Zhengying Wei, Ruwei Geng and Siyuan Xu, Numerical analysis of arc driving forces and temperature distribution in pulsed TIG welding, Journal of the Brazilian Society of Mechanical Sciences and Engineering, Vol. 41, No. 60, 2019. doi.org/10.1007/s40430-018-1563-0

    04-19   Santosh Reddy Sama, Tony Badamo, Paul Lynch and Guha Manogharan, Novel sprue designs in metal casting via 3D sand-printing, Additive Manufacturing, Vol. 25, pp. 563-578, 2019. doi.org/10.1016/j.addma.2018.12.009

    03-19   Dongsheng Wu, Anh Van Nguyen, Shinichi Tashiro, Xueming Hua and Manabu Tanaka, Elucidation of the weld pool convection and keyhole formation mechanism in the keyhold plasma arc welding, International Journal of Heat and Mass Transfer, Vol. 131, pp. 920-931, 2019. doi.org/10.1016/j.ijheatmasstransfer.2018.11.108

    97-18   Wentao Yan, Ya Qian, Wenjun Ge, Stephen Lin, Wing Kam Liu, Feng Lin, Gregory J. Wagner, Meso-scale modeling of multiple-layer fabrication process in Selective Electron Beam Melting: Inter-layer/track voids formation, Materials & Design, 2018. doi.org/10.1016/j.matdes.2017.12.031

    84-18   Bo Cheng, Xiaobai Li, Charles Tuffile, Alexander Ilin, Hannes Willeck and Udo Hartel, Multi-physics modeling of single track scanning in selective laser melting: Powder compaction effect, Proceedings of the 29th Annual International Solid Freeform Fabrication Symposium, pp. 1887-1902, 2018.

    81-18 Yufan Zhao, Yuichiro Koizumi, Kenta Aoyagi, Daixiu Wei, Kenta Yamanaka and Akihiko Chiba, Molten pool behavior and effect of fluid flow on solidification conditions in selective electron beam melting (SEBM) of a biomedical Co-Cr-Mo alloy, Additive Manufacturing, Vol. 26, pp. 202-214, 2019. doi.org/10.1016/j.addma.2018.12.002

    77-18   Jun Du and Zhengying Wei, Numerical investigation of thermocapillary-induced deposited shape in fused-coating additive manufacturing process of aluminum alloy, Journal of Physics Communications, Vol. 2, No. 11, 2018. doi.org/10.1088/2399-6528/aaedc7

    76-18   Yu Xiang, Shuzhe Zhang, Zhengying We, Junfeng Li, Pei Wei, Zhen Chen, Lixiang Yang and Lihao Jiang, Forming and defect analysis for single track scanning in selective laser melting of Ti6Al4V, Applied Physics A, 124:685, 2018. doi.org/10.1007/s00339-018-2056-9

    74-18   Paree Allu, CFD simulations for laser welding of Al Alloys, Proceedings, Die Casting Congress & Exposition, Indianapolis, IN, October 15-17, 2018.

    72-18   Hunchul Jeong, Kyungbae Park, Sungjin Baek, Dong-Yoon Kim, Moon-Jin Kang and Jungho Cho, Three-dimensional numerical analysis of weld pool in GMAW with fillet joint, International Journal of Precision Engineering and Manufacturing, Vol. 19, No. 8, pp. 1171-1177, 2018. doi.org/10.1007/s12541-018-0138-4

    60-18   R.W. Geng, J. Du, Z.Y. Wei and G.X. Zhao, An adaptive-domain-growth method for phase field simulation of dendrite growth in arc preheated fused-coating additive manufacturing, IOP Conference Series: Journal of Physics: Conference Series 1063, 012077, 2018. doi.org/10.1088/1742-6596/1063/1/012077

    59-18   Guangxi Zhao, Jun Du, Zhengying Wei, Ruwei Geng and Siyuan Xu, Coupling analysis of molten pool during fused coating process with arc preheating, IOP Conference Series: Journal of Physics: Conference Series 1063, 012076, 2018. doi.org/10.1088/1742-6596/1063/1/012076 (Available at http://iopscience.iop.org/article/10.1088/1742-6596/1063/1/012076/pdf and in shared drive)

    58-18   Siyuan Xu, Zhengying Wei, Jun Du, Guangxi Zhao and Wei Liu, Numerical simulation and analysis of metal fused coating forming, IOP Conference Series: Journal of Physics: Conference Series 1063, 012075, 2018. doi.org/10.1088/1742-6596/1063/1/012075

    55-18   Jason Cheon, Jin-Young Yoon, Cheolhee Kim and Suck-Joo Na, A study on transient flow characteristic in friction stir welding with realtime interface tracking by direct surface calculation, Journal of Materials Processing Tech., vol. 255, pp. 621-634, 2018.

    54-18   V. Sukhotskiy, P. Vishnoi, I. H. Karampelas, S. Vader, Z. Vader, and E. P. Furlani, Magnetohydrodynamic drop-on-demand liquid metal additive manufacturing: System overview and modeling, Proceedings of the 5th International Conference of Fluid Flow, Heat and Mass Transfer, Niagara Falls, Canada, June 7 – 9, 2018; Paper no. 155, 2018. doi.org/10.11159/ffhmt18.155

    52-18   Michael Hilbinger, Claudia Stadelmann, Matthias List and Robert F. Singer, Temconex® – Kontinuierliche Pulverextrusion: Verbessertes Verständnis mit Hilfe der numerischen Simulation, Hochleistungsmetalle und Prozesse für den Leichtbau der Zukunft, Tagungsband 10. Ranshofener Leichtmetalltage, 13-14 Juni 2018, Linz, pp. 175-186, 2018.

    38-18   Zhen Chen, Yu Xiang, Zhengying Wei, Pei Wei, Bingheng Lu, Lijuan Zhang and Jun Du, Thermal dynamic behavior during selective laser melting of K418 superalloy: numerical simulation and experimental verification, Applied Physics A, vol. 124, pp. 313, 2018. doi.org/10.1007/s00339-018-1737-8

    19-18   Chenxiao Zhu, Jason Cheon, Xinhua Tang, Suck-Joo Na, and Haichao Cui, Molten pool behaviors and their influences on welding defects in narrow gap GMAW of 5083 Al-alloy, International Journal of Heat and Mass Transfer, vol. 126:A, pp.1206-1221, 2018. doi.org/10.1016/j.ijheatmasstransfer.2018.05.132

    16-18   P. Schneider, V. Sukhotskiy, T. Siskar, L. Christie and I.H. Karampelas, Additive Manufacturing of Microfluidic Components via Wax Extrusion, Biotech, Biomaterials and Biomedical TechConnect Briefs, vol. 3, pp. 162 – 165, 2018.

    09-18   The Furlani Research Group, Magnetohydrodynamic Liquid Metal 3D Printing, Department of Chemical and Biological Engineering, © University at Buffalo, May 2018.

    08-18   Benjamin Himmel, Dominik Rumschöttel and Wolfram Volk, Thermal process simulation of droplet based metal printing with aluminium, Production Engineering, March 2018 © German Academic Society for Production Engineering (WGP) 2018.

    07-18   Yu-Che Wu, Cheng-Hung San, Chih-Hsiang Chang, Huey-Jiuan Lin, Raed Marwan, Shuhei Baba and Weng-Sing Hwang, Numerical modeling of melt-pool behavior in selective laser melting with random powder distribution and experimental validation, Journal of Materials Processing Tech. 254 (2018) 72–78.

    60-17   Pei Wei, Zhengying Wei, Zhen Chen, Yuyang He and Jun Du, Thermal behavior in single track during selective laser melting of AlSi10Mg powder, Applied Physics A: Materials Science & Processing, 123:604, 2017. doi.org/10.1007/z00339-017-1194-9

    51-17   Koichi Ishizaka, Keijiro Saitoh, Eisaku Ito, Masanori Yuri, and Junichiro Masada, Key Technologies for 1700°C Class Ultra High Temperature Gas Turbine, Mitsubishi Heavy Industries Technical Review, vol. 54, no. 3, 2017.

    49-17   Yu-Che Wu, Weng-Sing Hwang, Cheng-Hung San, Chih-Hsiang Chang and Huey-Jiuan Lin, Parametric study of surface morphology for selective laser melting on Ti6Al4V powder bed with numerical and experimental methods, International Journal of Material Forming, © Springer-Verlag France SAS, part of Springer Nature 2017. doi.org/10.1007/s12289-017-1391-2.

    37-17   V. Sukhotskiy, I. H. Karampelas, G. Garg, A. Verma, M. Tong, S. Vader, Z. Vader, and E. P. Furlani, Magnetohydrodynamic Drop-on-Demand Liquid Metal 3D Printing, Solid Freeform Fabrication 2017: Proceedings of the 28th Annual International Solid Freeform Fabrication Symposium – An Additive Manufacturing Conference

    15-17   I.H. Karampelas, S. Vader, Z. Vader, V. Sukhotskiy, A. Verma, G. Garg, M. Tong and E.P. Furlani, Drop-on-Demand 3D Metal Printing, Informatics, Electronics and Microsystems TechConnect Briefs 2017, Vol. 4

    14-17   Jason Cheon and Suck-Joo Na, Prediction of welding residual stress with real-time phase transformation by CFD thermal analysis, International Journal of Mechanical Sciences 131–132 (2017) 37–51.

    91-16   Y. S. Lee and D. F. Farson, Surface tension-powered build dimension control in laser additive manufacturing process, Int J Adv Manuf Technol (2016) 85:1035–1044, doi.org/10.1007/s00170-015-7974-5.

    84-16   Runqi Lin, Hui-ping Wang, Fenggui Lu, Joshua Solomon, Blair E. Carlson, Numerical study of keyhole dynamics and keyhole-induced porosity formation in remote laser welding of Al alloys, International Journal of Heat and Mass Transfer 108 (2017) 244–256, Available online December 2016.

    68-16   Dongsheng Wu, Xueming Hua, Dingjian Ye and Fang Li, Understanding of humping formation and suppression mechanisms using the numerical simulation, International Journal of Heat and Mass Transfer, Volume 104, January 2017, Pages 634–643, Published online 2016.

    39-16   Chien-Hsun Wang, Ho-Lin Tsai, Yu-Che Wu and Weng-Sing Hwang, Investigation of molten metal droplet deposition and solidification for 3D printing techniques, IOP Publishing, J. Micromech. Microeng. 26 (2016) 095012 (14pp), doi: 10.1088/0960-1317/26/9/095012, July 8, 2016

    29-16   Scott Vader, Zachary Vader, Ioannis H. Karampelas and Edward P. Furlani, Advances in Magnetohydrodynamic Liquid Metal Jet Printing, Nanotech 2016 Conference & Expo, May 22-25, Washington, DC.

    26-16   Y.S. Lee and W. Zhang, Modeling of heat transfer, fluid flow and solidification microstructure of nickel-base superalloy fabricated by laser powder bed fusion, S2214-8604(16)30087-2, doi.org/10.1016/j.addma.2016.05.003, ADDMA 86.

    123-15   Koji Tsukimoto, Masashi Kitamura, Shuji Tanigawa, Sachio Shimohata, and Masahiko Mega, Laser welding repair for single crystal blades, Proceedings of International Gas Turbine Congress, pp. 1354-1358, 2015.

    122-15   Y.S. Lee, W. Zhang, Mesoscopic simulation of heat transfer and fluid flow in laser powder bed additive manufacturing, Proceedings, 26th Solid Freeform Fabrication Symposium, Austin, Texas, 2015. 

    116-15   Yousub Lee, Simulation of Laser Additive Manufacturing and its Applications, Ph.D. Thesis: Graduate Program in Welding Engineering, The Ohio State University, 2015, Copyright by Yousub Lee 2015

    103-15   Ligang Wu, Jason Cheon, Degala Venkata Kiran, and Suck-Joo Na, CFD Simulations of GMA Welding of Horizontal Fillet Joints based on Coordinate Rotation of Arc Models, Journal of Materials Processing Technology, Available online December 29, 2015

    96-15   Jason Cheon, Degala Venkata Kiran, and Suck-Joo Na, Thermal metallurgical analysis of GMA welded AH36 steel using CFD – FEM framework, Materials & Design, Volume 91, February 5 2016, Pages 230-241, published online November 2015

    86-15   Yousub Lee and Dave F. Farson, Simulation of transport phenomena and melt pool shape for multiple layer additive manufacturing, J. Laser Appl. 28, 012006 (2016). doi: 10.2351/1.4935711, published online 2015.

    63-15   Scott Vader, Zachary Vader, Ioannis H. Karampelas and Edward P. Furlani, Magnetohydrodynamic Liquid Metal Jet Printing, TechConnect World Innovation Conference & Expo, Washington, D.C., June 14-17, 2015

    46-15   Adwaith Gupta, 3D Printing Multi-Material, Single Printhead Simulation, Advanced Qualification of Additive Manufacturing Materials Workshop, July 20 – 21, 2015, Santa Fe, NM

    25-15   Dae-Won Cho and Suck-Joo Na, Molten pool behaviors for second pass V-groove GMAW, International Journal of Heat and Mass Transfer 88 (2015) 945–956.

    21-15   Jungho Cho, Dave F. Farson, Kendall J. Hollis and John O. Milewski, Numerical analysis of weld pool oscillation in laser welding, Journal of Mechanical Science and Technology 29 (4) (2015) 1715~1722, www.springerlink.com/content/1738-494x, doi.org/10.1007/s12206-015-0344-2.

    82-14  Yousub Lee, Mark Nordin, Sudarsanam Suresh Babu, and Dave F. Farson, Effect of Fluid Convection on Dendrite Arm Spacing in Laser Deposition, Metallurgical and Materials Transactions B, August 2014, Volume 45, Issue 4, pp 1520-1529

    59-14   Y.S. Lee, M. Nordin, S.S. Babu, and D.F. Farson, Influence of Fluid Convection on Weld Pool Formation in Laser Cladding, Welding Research/ August 2014, VOL. 93

    18-14  L.J. Zhang, J.X. Zhang, A. Gumenyuk, M. Rethmeier, and S.J. Na, Numerical simulation of full penetration laser welding of thick steel plate with high power high brightness laser, Journal of Materials Processing Technology (2014), doi.org/10.1016/j.jmatprotec.2014.03.016.

    36-13  Dae-Won Cho,Woo-Hyun Song, Min-Hyun Cho, and Suck-Joo Na, Analysis of Submerged Arc Welding Process by Three-Dimensional Computational Fluid Dynamics Simulations, Journal of Materials Processing Technology, 2013. doi.org/10.1016/j.jmatprotec.2013.06.017

    12-13 D.W. Cho, S.J. Na, M.H. Cho, J.S. Lee, A study on V-groove GMAW for various welding positions, Journal of Materials Processing Technology, April 2013, doi.org/10.1016/j.jmatprotec.2013.02.015.

    01-13  Dae-Won Cho & Suck-Joo Na & Min-Hyun Cho & Jong-Sub Lee, Simulations of weld pool dynamics in V-groove GTA and GMA welding, Weld World, doi.org/10.1007/s40194-012-0017-z, © International Institute of Welding 2013.

    63-12  D.W. Cho, S.H. Lee, S.J. Na, Characterization of welding arc and weld pool formation in vacuum gas hollow tungsten arc welding, Journal of Materials Processing Technology, doi.org/10.1016/j.jmatprotec.2012.09.024, September 2012.

    77-10  Lim, Y. C.; Yu, X.; Cho, J. H.; et al., Effect of magnetic stirring on grain structure refinement Part 1-Autogenous nickel alloy welds, Science and Technology of Welding and Joining, Volume: 15 Issue: 7, Pages: 583-589, doi.org/10.1179/136217110X12720264008277, October 2010

    18-10 K Saida, H Ohnishi, K Nishimoto, Fluxless laser brazing of aluminium alloy to galvanized steel using a tandem beam–dissimilar laser brazing of aluminium alloy and steels, Welding International, 2010

    58-09  Cho, Jung-Ho; Farson, Dave F.; Milewski, John O.; et al., Weld pool flows during initial stages of keyhole formation in laser welding, Journal of Physics D-Applied Physics, Volume: 42 Issue: 17 Article Number: 175502 ; doi.org/10.1088/0022-3727/42/17/175502, September 2009

    57-09  Lim, Y. C.; Farson, D. F.; Cho, M. H.; et al., Stationary GMAW-P weld metal deposit spreading, Science and Technology of Welding and Joining, Volume: 14 Issue: 7 ;Pages: 626-635, doi.org/10.1179/136217109X441173, October 2009

    1-09 J.-H. Cho and S.-J. Na, Three-Dimensional Analysis of Molten Pool in GMA-Laser Hybrid Welding, Welding Journal, February 2009, Vol. 88

    52-07   Huey-Jiuan Lin and Wei-Kuo Chang, Design of a sheet forming apparatus for overflow fusion process by numerical simulation, Journal of Non-Crystalline Solids 353 (2007) 2817–2825.

    50-07  Cho, Min Hyun; Farson, Dave F., Understanding bead hump formation in gas metal arc welding using a numerical simulation, Metallurgical and Mateials Transactions B-Process Metallurgy and Materials Processing Science, Volume: 38, Issue: 2, Pages: 305-319, doi.org/10.1007/s11663-007-9034-5, April 2007

    49-07  Cho, M. H.; Farson, D. F., Simulation study of a hybrid process for the prevention of weld bead hump formation, Welding Journal Volume: 86, Issue: 9, Pages: 253S-262S, September 2007

    48-07  Cho, M. H.; Farson, D. F.; Lim, Y. C.; et al., Hybrid laser/arc welding process for controlling bead profile, Science and Technology of Welding and Joining, Volume: 12 Issue: 8, Pages: 677-688, doi.org/10.1179/174329307X236878, November 2007

    47-07   Min Hyun Cho, Dave F. Farson, Understanding Bead Hump Formation in Gas Metal Arc Welding Using a Numerical Simulation, Metallurgical and Materials Transactions B, Volume 38, Issue 2, pp 305-319, April 2007

    36-06  Cho, M. H.; Lim, Y. C.; Farson, D. F., Simulation of weld pool dynamics in the stationary pulsed gas metal arc welding process and final weld shape, Welding Journal, Volume: 85 Issue: 12, Pages: 271S-283S, December 2006

    래스터 파일 사용 및 가져오기

    Using and Importing Raster Files

    GIS 어플리케이션과 관련하여, 래스터 데이터는 공간 데이터가 셀의 행렬로 표현되는 현실 세계의 추상화입니다. 데이터의 위치는 값의 순서에 내재되어 있으며 ASCII 형식의 행과 열로 구성된 균일 한 x 및 y 위치를 사용합니다. 행과 열의 각 데이터 값은 수량을 나타냅니다. FLOW-3D에서 이것은 표면 높이 또는 표면 거칠기 일 수 있습니다. 지표면 고도 인 경우 FLOW-3D는 정보를 사용하여 고도 값을 기반으로 토폴로지를 작성합니다. 거칠기가있는 경우 데이터는 표면 변형의 크기를 나타내거나 Manning의 n과 상관 관계가 있습니다. 이 정보는 궁극적으로 흐름에 대한 저항력 (마찰 계수)을 나타냅니다. 이 기사에서는 FLOW-3D의 토폴로지와 표면 거칠기에 대해 래스터 파일을 사용하는 방법에 대해 설명합니다.

    Format

    여기에 표시된 것은 래스터 파일을 FLOW-3D로 읽는 데 필요한 형식입니다. 6 개의 행의 헤더 데이터와 그 다음에 표면 높이 또는 표면 거칠기를 나타내는 행과 열의 행렬이옵니다. 헤더 데이터에는 다음이 포함됩니다.
    – ncols = 데이터 열 수 (즉, x 방향의 위치)
    – nrows = 데이터 행 수 (즉, y 방향의 위치)
    – xllcorner = 래스터 그리드에서 x 최소 좌표를 식별합니다. 값은 래스터 셀의 절반만큼 오른쪽으로 이동합니다. 셀 가장자리에 있지 않습니다.
    – yllcorner  = 래스터 그리드에서 y 최소 좌표를 식별합니다. 값은 래스터 셀의 절반만큼 위쪽으로 이동합니다. 셀 가장자리에 있지 않습니다.
    – cellsize = 각 데이터 포인트 간의 x와 y 간격
    – nodata_value = 주어진 위치에 값이 없음을 의미하는 값

    Importing a raster file

    래스터 파일을 가져 오려면 그림 2와 같이 Meshing & Geometry 탭 아래의 ASC 버튼을 새 구성 요소로 선택합니다. 그런 다음 Add 버튼을 선택하고 파일을 탐색합니다. 파일을 추가하고 OK를 선택하면 Solid 또는 Surface Roughness로 추가하라는 메시지가 나타납니다.

    그림 3의 대화 상자는 솔리드 서피스로 가져올 지 표면 거칠기로 가져올지를 선택하는 것이며 새 구성 요소를 추가 할 때만 나타납니다. 기존 구성 요소에 추가 할 때마다 유형이 기존 구성 요소 정의의 유형과 자동으로 일치하도록 결정됩니다. 솔리드 유형 인 경우 각 가져 오기는 토폴로지로 간주되는 하위 구성 요소를 추가합니다. 표면 거칠기 유형 인 경우 각 가져 오기는 표면 거칠기로 간주되는 하위 구성 요소를 추가합니다.

    Import as a solid

    솔리드로 가져 오려면 솔리드 라디오 단추를 선택하고 원하는 경우 이름을 입력하십시오. 래스터 파일의 모든 nodata_value 데이터 포인트에는 누락 된 데이터를 높이를 나타내는 값으로 바꾸는 옵션이 GUI에 있습니다. 따라서 바닥을 만듭니다. GUI에서 이는 토폴로지를 나타내는 가져온 하위 구성 요소 목록 아래에 있습니다.

    Import as roughness

    거칠기로 가져 오려면 표면 거칠기 라디오 버튼을 선택하고 이름을 입력하십시오 (원하는 경우). 구성 요소 유형은 가져온 표면 거칠기입니다. 또한 필요한 범례 파일에 대한 프롬프트가 표시됩니다. 이 파일은 래스터 조도 파일의 정수 조도 코드와 FLOW-3D의 조도 조도 값을 관련시킵니다.
    범례 파일의 형식은 유연합니다. 헤더의 텍스트 정보는 관련 데이터가 첫 번째 행에서부터 읽혀지기 때문에 허용됩니다. 데이터는 공백, 탭 또는 쉼표로 구분할 수있는 두 개의 열로 구성됩니다. 첫 번째 열은 거친 파일의 정수 코드에 해당하고 두 번째 열은 FLOW-3D의 거칠기를 정의합니다.
    범례 파일은 전역 목록 아래의 기하학 트리 구조 아래에 추가됩니다.

    Applying roughness to components

    그림 6은 구성 요소 1이 토폴로지로 가져온 래스터 파일을 사용하여 솔리드를 나타내는 설치의 트리 구조를 나타냅니다. 구성 요소 2는 관련 범례 파일을 포함하는 거칠기로 가져온 래스터 파일을 사용하여 공간적으로 변화하는 표면 거칠기를 정의합니다. 그림과 같이 글로벌 목록 아래에 범례 파일에 대한 경로가 있습니다. 구성 요소 1의 구성 요소 유형은 단색입니다. 구성 요소 2는 표면 거칠기로 구성 요소 유형을 갖습니다.

    “표면 거칠기”구성 요소 (구성 요소 2)에 의해 정의 된 공간적으로 변화하는 표면 거칠기는 구성 요소 1의 표면 특성 섹션에서 “조도 파일 사용”플래그를 선택하여 토폴로지 구성 요소 (구성 요소 1)에 매핑됩니다 (그림 7 ). 이 플래그는 솔버가 구성 요소 2가 구성 요소 1과 겹치는 래스터 데이터에 정의 된 표면 거칠기를 사용하도록 지시합니다. 토폴로지 래스터 파일에 해당 위치에 “nodata_value”가 있으면 대신 구성 요소 1에 대해 정의 된 구성 요소 / 하위 구성 요소 조도를 사용합니다 .

    Transformation center

    가져온 래스터 데이터의 좌표는 종종 좌표 중심점 0,0,0에서 멀리 떨어진 위치를 가질 수 있기 때문에 회전 중심을 회전 및 확대 / 축소에 도움이되는 위치로 변경하는 옵션이 있습니다. 설정하지 않으면 회전 및 확대 / 축소가 좌표축 중심을 기준으로 발생합니다. 따라서 가져온 형상을 탐색하기가 어렵습니다.

    로컬 좌표 중심을 기준으로 구성 요소를 회전 시키려면 각 방향에서 최소 및 최대 범위의 평균값을 선택하십시오. 예를 들어, x-min이 9.98e6 미터이고 x-max가 9.96e6 미터 인 경우 평균값 (중간)은 9.97e6 미터입니다. 동일한 논리가 y 방향에 적용됩니다. 그림 8은 구성 요소 1에 대한 변형 중심을 설정하는 예입니다.

    Summary

    래스터 파일은 토폴로지와 표면 거칠기에 사용할 수있는 일반적인 지형 정보입니다. 이 데이터를 FLOW-3D로 직접 가져올 수 있으면 데이터를 간단하고 직접적으로 가져올 수 있습니다. 이 튜토리얼에서는 사용자가 래스터 데이터를 가져 와서 모델에 적용하는 방법을 알 수 있도록 프로세스를 설명합니다.

    The Sedimentation Scour Model [침전 세굴(쇄굴) 모델]

    1. Introduction
    The three-dimensional sediment scour model for non-cohesive soils was first introduced to FLOW-3D in Version 8.0 to simulate sediment erosion and deposition (Brethour, 2003). It was coupled with the three-dimensional fluid dynamics and considered entrainment, drifting and settling of sediment grains. In Version 9.4 the model was improved by introducing bedload transport and multiple sediment species (Brethour and Burnham, 2010). Although applications were successfully simulated, a major limitation of the model was the approximate treatment of the interface between the packed and suspended sediments. The packed bed was represented by scalars rather than FAVORTM (Fractional Area Volume Obstacle Representation, the standard treatment for solid components in FLOW-3D). As a result, limited information about the packed bed interface was available. That made accurate calculation of bed shear stress, a critical factor determining the model accuracy, challenging.

    In this work, the 3D sediment scour model is mostly redeveloped and rewritten. The model is still fully coupled with fluid flow, allows multiple non-cohesive species and considers entrainment, deposition, bedload transport and suspended load transport. The fundamental difference from the old model is that the packed bed is described by the FAVORTM technique. At each time step, area and volume fractions describing the packed sediments are calculated throughout the domain. In the mesh cells at the bed interface, the location, orientation and area of the interface are calculated and used to determine the bed shear stress, the critical Shields parameter, the erosion rate and the bedload transport rate. Bed shear stress is evaluated using the standard wall function with consideration of bed surface roughness that is related to the median grain size d50. A sub-mesh method is developed and implemented to calculate bedload transport. Computation of erosion considers entrainment and deposition simultaneously in addition to bedload transport.

    Furthermore, a shallow-water sediment scour model is developed in this work by adapting the new 3D model. It is coupled with the 2D shallow water flows to calculate depth-averaged properties for both suspended and packed sediments. Its main differences from the 3D model are 1) the settling velocity of grains is calculated using an existing equation instead of the drift-flux approach in the 3D model, and 2) turbulent bed shear stress is calculated using a well-accepted quadratic law rather than the log wall function. The drag coefficient for the bed shear stress is either user-given or locally evaluated using the water depth and the bed surface roughness that is proportional to d50 of the bed material. The following sections present the sediment theory used in the model and application and validation cases.

    Simulating the Residue left by Evaporating Drops

    Background
    The “coffee ring” effect is the name given to a well known observation where the evaporative drying of a drop of coffee leaves behind a ring of dark material at the edge of the original drop. On first thought one would expect that the coffee particles, which are uniformly distributed in the drop, would simply be deposited uniformly over the area wetted by the drop. It has only been in recent years that researchers have uncovered the mechanisms that produce the ring effect (Deegan, R.D., et al).
    As currently understood, the edges of drops can become pinned because of roughness or chemical elements on the surface on which they lie. Heat transfer to the drops from the substrate or the air induces evaporation, which is usually greater near the drop edge. Surface tension forces then adjust the curvature of the remaining liquid consistent with the pinned edge, which results in a net flow of liquid toward the edge. This flow replenishes the evaporative loss but also moves solute to the edge where it is concentrated by evaporation. Eventually, this mechanism builds up a ring deposit of solute at the original edge of the drop.
    The residue from dried drops has implications for many useful applications, including general coating processes, formation of pixel arrays of organic materials for video displays and for a variety of micro-electro-mechanical (MEMS) devices.
    Because many factors control the distribution of dried residue it is desirable to have some means to model the fluid dynamics of the process to aid engineers in making the best choices for each specific application. Such a capability has been incorporated into FLOW-3D1 making it possible to computationally investigate the influence of such parameters as the initial solute concentration, fluid viscosity, volatility of the solvent, evaporation rate, surface tension and initial shape of the drop.
    This technical note presents a brief description of the residue formation model and illustrates it with several computations of an evaporating drop subject to different physical conditions.

    Modeling Roughness Effects in Open Channel Flows

    Overview
    Flows along rivers, through pipes and irrigation channels encounter resistance that is proportional to the roughness of bounding walls. Roughness can vary considerably from smooth steel, to concrete or sand, pebbles, and even large boulders. In traditional hydraulics the influence of roughness has been cataloged in the form of a roughness coefficient based on data obtained from a wide range of field and laboratory observations.
    Roughness coefficients are typically defined in one of two ways: (1) Ch¾zy’s resistance coefficient, or (2) Manning’s n. To understand these terms we must first state the conditions under which they are defined. For this discussion, and much more information about flow resistance caused by roughness, the reader is referred to Open Channel Hydraulics by Ven Te Chow and published by McGraw-Hill, reissued 1988.
    Flow losses are defined in terms of a uniform flow state defined as steady flow with a fixed discharge and flow depth. In practice this usually means the flow in a channel of uniform cross section and having a constant slope such that the gravitational acceleration down the slope is balanced by frictional resistance at the boundaries of the channel.

    Coating Bibliography

    아래는 코팅 참고 문헌의 기술 문서 모음입니다. 
    이 모든 논문은 FLOW-3D  결과를 포함하고 있습니다. FLOW-3D를 사용하여 코팅 공정을 성공적으로 시뮬레이션  하는 방법에 대해 자세히 알아보십시오.

    Coating Bibliography

    2024년 11월 20일 Update

    98-24 Fabiano I. Indicatti, Bo Cheng, Michael Rädler, Elisabeth Stammen, Klaus Dilger, Experimental and numerical investigation of the squeegee process during stencil printing of thick adhesive sealings, The Journal of Adhesion, 2024. doi.org/10.1080/00218464.2024.2356105

    130-22   Md Didarul Islam, Himendra Perera, Benjamin Black, Matthew Phillips, Muh-Jang Chen, Greyson Hodges, Allyce Jackman, Yuxuan Liu, Chang-Jin Kim, Mohammed Zikry, Saad Khan, Yong Zhu, Mark Pankow, Jong Eun Ryu, Template-free scalable fabrication of linearly periodic microstructures by controlling ribbing defects phenomenon in forward roll coating for multifunctional applications, Advanced Materials Interfaces, 9.27; 2201237, 2022. doi.org/10.1002/admi.202201237

    03-21   Delong Jia, Peng Yi, Yancong Liu, Jiawei Sun, Shengbo Yue, Qi Zhao, Effect of laser­ textured groove wall interface on molybdenum coating diffusion and metallurgical bonding, Surface and Coatings Technology, 405; 126561, 2021. doi.org/10.1016/j.surfcoat.2020.126561

    50-19     Peng Yi, Delong Jia, Xianghua Zhan, Pengun Xu, and Javad Mostaghimi, Coating solidification mechanism during plasma-sprayed filling the laser textured grooves, International Journal of Heat and Mass Transfer, Vol. 142, 2019. doi:10.1016/j.ijheatmasstransfer.2019.118451

    01-19   Jelena Dinic and Vivek Sharma, Computational analysis of self-similar capillary-driven thinning and pinch-off dynamics during dripping using the volume-of-fluid method, Physics of Fluids, Vol. 31, 2019. doi: 10.1063/1.5061715

    85-18   Zia Jang, Oliver Litfin and Antonio Delgado, A semi-analytical approach for prediction of volume flow rate in nip-fed reverse roll coating process, Proceedings in Applied Mathematics and Mechanics, Vol. 18, no. 1, Special Issue: 89th Annual Meeting of the International Association of Applied Mathematics and Mechanics, 2018. doi: 10.1002/pamm.201800317

    80-14   Hiroaki Koyama, Kazuhiro Fukada, Yoshitaka Murakami, Satoshi Inoue, and Tatsuya Shimoda, Investigation of Roll-to-Sheet Imprinting for the Fabrication of Thin-film Transistor Electrodes, IEICE TRAN, ELECTRON, VOL.E97-C, NO.11, November 2014

    46-14   Isabell Vogeler, Andreas Olbers, Bettina Willinger and Antonio Delgado, Numerical investigation of the onset of air entrainment in forward roll coating, 17th International Coating Science and Technology Symposium September 7-10, 2014 San Diego, CA, USA

    17-12  Chi-Feng Lin, Bo-Kai Wang, Carlos Tiu and Ta-Jo Liu, On the Pinning of Downstream Meniscus for Slot Die Coating, Advances in Polymer Technology, Vol. 00, No. 0, 1-9 (2012) © 2012 Wiley Periodicals, Inc. Available online at Wiley.

    01-11  Reid Chesterfield, Andrew Johnson, Charlie Lang, Matthew Stainer, and Jonathan Ziebarth, Solution-Coating Technology for AMOLED Displays, Information Display Magazine, 1/11 0362-0972/01/2011-024 © SID 2011.

    61-09 Yi-Rong Chang, Chi-Feng Lin and Ta-Jo Liu, Start-up of slot die coating, Polymer Engineering and Science, Vol. 49, pp. 1158-1167, 2009. doi:10.1002/pen.21360

    26-06  James M. Brethour, 3-D transient simulation of viscoelastic coating flows, 13th International Coating Science and Technology Symposium, September 2006, Denver, Colorado

    19-06  Ivosevic, M., Cairncross, R. A., and Knight, R., 3D Predictions of Thermally Sprayed Polymer Splats Modeling Particle Acceleration, Heating and Deformation on Impact with a Flat Substrate, Int. J. of Heat and Mass Transfer, 49, pp. 3285 – 3297, 2006

    9-06  M. Ivosevic, R. A. Cairncross, R. Knight, T. E. Twardowski, V. Gupta, Drexel University, Philadelphia, PA; J. A. Baldoni, Duke University, Durham, NC, Effect of Substrate Roughness on Splatting Behavior of HVOF Sprayed Polymer Particles Modeling and Experiments, International Thermal Spray Conference, Seattle, WA, May 2006.

    26-05  Ivosevic, M., Cairncross, R. A., Knight, R., Impact Modeling of Thermally Sprayed Polymer Particles, Proc. International Thermal Spray Conference [ITSC-2005], Eds., DVS/IIW/ASM-TSS, Basel, Switzerland, May 2005.

    11-05  Brethour, J., Simulation of Viscoelastic Coating Flows with a Volume-of-fluid Technique, in Proceedings of the 6th European Coating Symposium, Bradford, UK, 2005

    1-05 C.W. Hirt, Electro-Hydrodynamics of Semi-Conductive Fluids: With Application to Electro-Spraying, Flow Science Technical Note #70, FSI-05-TN70

    38-04 K.H. Ho and Y.Y. Zhao, Modelling thermal development of liquid metal flow on rotating disc in centrifugal atomisation, Materials Science and Engineering, A365, pp. 336-340, 2004. doi:10.1016/j.msea.2003.09.044

    30-04  M. Ivosevic, R.A. Cairncross, and R. Knight, Impact Modeling of HVOF Sprayed Polymer Particles, Presented at the 12th International Coating Science and Technology Symposium, Rochester, New York, September 23-25, 2004

    29-04  J.M. Brethour and C.W. Hirt, Stains Arising from Dried Liquid Drops, Presented at the 12th International Coating Science and Technology Symposium, Rochester, New York, September 23-25, 2004

    20-03  James Brethour, Filling and Emptying of Gravure Cells–A CFD Analysis, Convertech Pacific October 2002, Vol. 10, No 4, p 34-37

    4-03   M. Toivakka, Numerical Investigation of Droplet Impact Spreading in Spray Coating of Paper, In Proceedings of 2003 TAPPI 8th Advanced Coating Fundamentals Symposium, TAPPI Press, Atlanta, 2003

    28-02  J.M. Brethour and H. Benkreira, Filling and Emptying of Gravure Cells—Experiment and CFD Comparison, 11th International Coating Science and Technology Symposium, September 23-25, 2002, Minneapolis, Minnesota

    22-02  Hirt, C.W., and Brethour, J.M., Contact Line on Rough Surfaces with Application to Air Entrainment, Presented at the 11th International Coating Science and Technology Symposium, September 23-25, 2002, Minneapolis, Minnesota. Unpublished.

    17-01  J. M. Brethour, C. W. Hirt, Moving Contact Lines on Rough Surfaces, 4th European Coating Symposium, 2001, Belgium

    16-01  J. M. Brethour, Filling and Emptying of Gravure Cells–-A CFD Analysis, proceedings of the 4th European Coating Symposium 2001, October 1-4, 2001, Brussels, Belgium

    26-00 Ronald H. Miller and Gary S. Strumolo, A Self-Consistent Transient Paint Simulation, Proceedings of IMEC2000: 2000 ASME International Mechanical Engineering Congress and Exposition, November 2000, Orlando, Florida

    6-99  C. W. Hirt, Direct Computation of Dynamic Contact Angles and Contact Lines, ECC99 Coating Conference, Erlangen, Germany (FSI-99-00-2), Sept. 1999

    7-98 J. E. Richardson and Y. Becker, Three-Dimensional Simulation of Slot Coating Edge Effects, Flow Science Inc, and Polaroid Corporation, presented at the 9th International Coating Science and Technology Symposium, Newark, DE, May 18-20, 1998

    6-98  C. W. Hirt and E. Choinski, Simulation of the Wet-Start Process in Slot Coating, Flow Science Inc, and Polaroid Corporation, presented at the 9th International Coating Science and Technology Symposium, Newark, DE, May 18-20, 1998

    3-97  C. W. Hirt and J. E. Richardson of Flow Science Inc, and K.S. Chen, Sandia National Laboratory, Simulation of Transient and Three-Dimensional Coating Flows Using a Volume-of-Fluid Technique, presented at the 50th Annual Conference of the Society for Imaging and Science Technology, Boston, MA 18-23 May 1997

    2-96 C. W. Hirt, K. S. Chen, Simulation of Slide-Coating Flows Using a Fixed Grid and a Volume-of-Fluid Front-Tracking Technique, presented a the 8th International Coating Process Science & Technology Symposium, February 25-29, 1996, New Orleans, LA

    Water & Environmental Bibliography

    다음은 수자원 및 환경 분야에 대한 참고 문 기술 문서 모음입니다.
    이 모든 논문은 FLOW-3D  해석 결과를 사용하였습니다. FLOW-3D  를 사용하여 수처리 및 환경 산업을 위한 응용 프로그램을 성공적으로 시뮬레이션하는 방법에 대해 자세히 알아보십시오.

    Water and Environmental Bibliography

    2024년 11월 20일 Update

    118-24 Lei Liao, Jia Li, Min Chen, Ruidong An, Effects of hydraulic cues in barrier environments on fish navigation downstream of dams, Journal of Environmental Management, 365; 121495, 2024. doi.org/10.1016/j.jenvman.2024.121495

    115-24 H. Liu, Y.G. Cheng, Z.Y. Yang, J. Zhang, J.Y. Fan, W.X. Li, Effect of uneven inflow on hydrodynamic performance of bulb turbine, Journal of Physics: Conference Series, 2752; 012032, 2024. doi.org/10.1088/1742-6596/2752/1/012032

    112-24 Jian Guo, Bowen Weng, Jiyi Wu, Investigation of the energy loss in cylindrical bridge piers scour depth prediction on sand-bed, Ocean Engineering, 309.1; 118513, 2024. doi.org/10.1016/j.oceaneng.2024.118513

    110-24 Siyu Chen, Xiyen Liu, Junyao Tang, Ying Gao, Tianyou Zhang, Linhao Gu, Tao Ma, Can Chen, Study on the influence of design parameters of porous asphalt pavement on drainage performance, Journal of Hydrology, 638; 131514, 2024. doi.org/10.1016/j.jhydrol.2024.131514

    108-24 Abubaker Sami Dheyab, Mustafa Günal, Experimental and numerical study for local scour around cylindrical bridge pier in non-cohesive sediment bed, 4th International Congress of Engineering and Natural Sciences (ICENSS), 2024.

    106-24 P. Asabian, C.D. Rennie, N. Egsgard, Experimental and numerical investigation of the flow-structure of river surf waves, River Flow 2022, eds. Ana Maria Ferreira da Silva, Colin Rennie, Susan Gaskin, Jay Lacey, Bruce MacVicar, 2024.

    105-24 M. Cihan Aydin, Ali Emre Ulu, Ercan Işık, Nizamettin Hamidi, An experimental and numerical investigation of hydraulic performance of in-channel triangular labyrinth weir for free overflow, ISH Journal of Hydraulic Engineering, pp. 1-10, 2024. doi.org/10.1080/09715010.2024.2363224

    103-24 Yazhou Wang, Jinrong Da, Yuchen Luo, Sirui He, Zuocong Tian, Ziyi Xue, Zehao Li, Xianyu Zhao, Desheng Yin, Hui Peng, Xiang Liu, Xiaoning Liu , Minimization of heavy metal adsorption in struvite through effective separation and manipulation of flow field, Journal of Hazardous Materials, 474; 134820, 2024. doi.org/10.1016/j.jhazmat.2024.134820

    101-24 Davut Yilmaz, Tugce Basar, Arzu Ozkaya, Assessing the pressure variation in the plunge pool of Yusufeli dam, Dams and Reservoirs, 2024. doi.org/10.1680/jdare.2024.1

    99-24 Azim Turan, High resolution flash flood forecasting by combining a hydrometeorological modeling system with a computational fluid dynamics model, Thesis, Middle East Technical University, 2024.

    97-24 Umut Aykan, Numerical investigation of vortex formation at single and multiple symmetric horizontal intakes, Thesis, Middle East Technical University, 2024.

    91-24 Di Wang, Xiaoyong Cheng, Zhixuan Cao, Jinyun Deng, Three-dimensional flow structure in a confluence-bifurcation unit, Engineering Applications of Computational Fluid Mechanics, 18.1; 2024. doi.org/10.1080/19942060.2024.2349076

    86-24 M.Z. Qamar, M.K. Verma, A.P. Meshram, Physical and numerical modelling for settling efficiency of desilting chamber, ISH Journal of Hydraulic Engineering, 30.3; 2024. doi.org/10.1080/09715010.2024.2345338

    85-24 Ruichen Xu, Duane C. Chapman, Caroline M. Elliott, Bruce C. Call, Robert B. Jacobson, Binbin Wang, Ecological inferences on invasive carp survival using hydrodynamics and egg drift models, Scientific Reports, 14; 9556, 2024. doi.org/10.1038/s41598-024-60189-1

    84-24 M. Cihan Aydin, Ali Emre Ulu, Ercan Işik, Experimental and numerical investigation of rectangular labyrinth weirs in an open channel, Water Management , 2024. doi.org/10.1680/jwama.22.00112

    76-24 Chyan-Deng Jan, Litan Dey, Slump-flow channel test for evaluating the relations between spreading and rheological parameters of sediment mixtures, European Journal of Mechanics – B/Fluids, 106; pp. 137-147, 2024. doi.org/10.1016/j.euromechflu.2024.04.005

    74-24 Abhishek K. Pandey, Pranab K. Mohapatra, 3D numerical simulations of the bed evolution at an open-channel junction in flood conditions, Journal of Irrigation and Drainage Engineering, 150.3; 2024. doi.org/10.1061/JIDEDH.IRENG-10321

    70-24 Jianing Rao, Qi Wei, Lian Tang, Yuanming Wang, Ruifeng Liang, Kefeng Li, A design of a nature-like fishway to solve the fractured river connectivity caused by small hydropower based on hydrodynamics and fish behaviors, Environmental Science and Pollution Research, 31; pp. 27883-27896, 2024. doi.org/10.1007/s11356-024-33034-1

    69-24 M. Cihan Aydin, Ali Emre Ulu, Ercan Işık, Determination of effective flow behaviors on discharge performance of trapezoidal labyrinth weirs using numerical and physical models, Modeling Earth Systems and Environment, 10; pp. 3763-3776, 2024. doi.org/10.1007/s40808-024-01996-3

    62-24 Ramtin Sabeti, Mohammad Heidarzadeh, Estimating maximum initial wave amplitude of subaerial landslide tsunamis: A three-dimensional modelling approach, Ocean Modelling, 189; 102360, 2024. doi.org/10.1016/j.ocemod.2024.102360

    60-24 Mahdi Ebrahimi, Mirali Mohammadi, Sayed Mohammad Hadi Meshkati, Farhad Imanshoar, Embankment dams overtopping breach: A numerical investigation of hydraulic results, Iranian Journal of Science and Technology: Transactions of Civil Engineering, 2024. doi.org/10.1007/s40996-024-01387-9

    59-24 Behshad Mardasi, Rasoul Ilkhanipour Zeynali, Majid Heydari, Conducting experimental and numerical studies to analyze the impact of the base nose shape on flow hydraulics in PKW weir using FLOW-3D, Journal of Hydraulic Structures, 9.4; pp. 88-113, 2024. doi.org/10.22055/JHS.2024.45888.1284

    58-24 Ramtin Sabeti, Mohammad Heidarzadeh, Alessandro Romano, Gabriel Barajas Ojeda, Javier L. Lara, Three-dimensional simulations of subaerial landslide-generated waves: Comparing OpenFOAM and FLOW-3D HYDRO models, Pure and Applied Geophysics, 181; pp. 1075-1093, 2024. doi.org/10.1007/s00024-024-03443-x

    56-24 Ali Poorkarimi, Khaled Mafakheri, Shahrzad Maleki, Effect of inlet and baffle position on the removal efficiency of sedimentation tank using FLOW-3D software, Journal of Hydraulic Structures, 9.4; pp. 76-87, 2024. doi.org/10.22055/jhs.2024.44817.1265

    55-24 P Sujith Nair, Aniruddha D. Ghare, Ankur Kapoor, An approach to hydraulic design of conical central baffle flumes, Flow Measurement and Instrumentation, 97; 102573, 2024. doi.org/10.1016/j.flowmeasinst.2024.102573

    54-24 Isabelle Cheff, Julie Taylor, Andrew Mitchell, Kathleen Horita, Darren Shepherd, Steven Rintoul, Rob Millar, Evaluating uncertainty in debris flood modelling for the design of a steep built channel, EGU General Assembly, EGU24-20781, 2024. doi.org/10.5194/egusphere-egu24-20781

    53-24 Antonija Harasti, Gordon Gilja, Josip Vuco, Jelena Boban, Manousos Valyrakis, Temporal development of the scour hole next to the riprap sloping structure, EGU General Assembly, EGU24-10349, 2024. doi.org/10.5194/egusphere-egu24-10349

    52-24 Gordon Gilja, Antonija Harasti, Dea Delija, Iva Mejašić, Manousos Valyrakis, Change in flow field next to riprap sloping structure caused by variability of scoured bathymetry, EGU General Assembly, EGU24-10417, 2024. doi.org/10.5194/egusphere-egu24-10417

    49-24 Mehdi Hamidi, Mehran Sadeqlu, Ali Mahdian Khalili, Investigating the design and arrangement of dual submerged vanes as mitigation countermeasure of bridge pier scour depth using a numerical approach, Ocean Engineering, 299; 117270, 2024. doi.org/10.1016/j.oceaneng.2024.117270

    48-24 Yingying Wang, Mouchao Lv, Wen’e Wang, Ming Meng, Discharge formula and hydraulics of rectangular side weirs in the small channel and field inlet, Water, 16.5; 713, 2024. doi.org/10.3390/w16050713

    45-24 José Saldanha Matos, Filipa Ferreira, Lisbon Master Plans and nature-based solutions, Urban Green Spaces – New Perspectives for Urban Resilience, Eds. Cristina M. Monteiro, Cristina Santos, Cristina Matos, Ana Briga Sá. doi.org/10.5772/intechopen.113870

    44-24 Muhanad Al-Jubouri, Richard P. Ray, Enhancing pier local scour prediction in the presence of floating debris, Pollack Periodica, 2024. doi.org/10.1556/606.2023.00952

    42-24 Huanquan Yang, Jiabao Ma, Xueying Liu, Numerical simulation research on energy dissipation characteristics of fish scale weir, ES3 Web of Conferences, 490; 03005, 2024. doi.org/10.1051/e3sconf/202449003005

    39-24 Henry-John Wright, Investigation of novel deflector shapes for uncontrolled spillways, Thesis, Stellenbosch University, 2024.

    37-24 Filipe Romão, Ana L. Quaresma, Joana Simão, Francisco J. Bravo-Córdoba, Teresa Viseu, José M. Santos, Francisco J. Sanz-Ronda, António N. Pi, Debating the rules: an experimental approach to assess cyprinid passage performance thresholds in vertical slot fishways, Water, 16.3; 439, 2024. doi.org/10.3390/w16030439

    36-24 Berkay Erat, Efe Barbaros, Kerem Taştan, Experimental and numerical investigation on flow and scour upstream of pipe intake structures, Arabian Journal for Science and Engineering, 49; pp. 5973-5987, 2024. doi.org/10.1007/s13369-023-08539-5

    31-24 Mahmoud T. Ghonim, Ashraf Jatwary, Magdy H. Mowafy, Martina Zelenakova, Hany F. Abd-Elhamid, H. Omara, Hazem M. Eldeeb, Estimating the peak outflow and maximum erosion rate during the breach of embankment dam, Water, 16.3; 399, 2024. doi.org/10.3390/w16030399

    30-24 Deli Qiu, Jiangdong Xu, Hai Lin, Numerical analysis of the overtopping failure of the tailings dam model based on inception similarity optimization, Applied Sciences, 14.3; 990, 2024. doi.org/10.3390/app14030990

    29-24 Tino Kostić, Yuanjie Ren, Stephan Theobald, 3D-CFD analysis of bedload transport in channel bifurcations, Journal of Hydroinformatics, 26.2; 480, 2024. doi.org/10.2166/hydro.2024.175

    28-24 Chenhao Zhang, Xin Li, Renyu Zhou, Bernard A. Engel, Yubao Wang, Hydraulic characteristics and flow measurement performance of portable primary and subsidiary fish-shaped flumes in U-shaped channels, Flow Measurement and Instrumentation, 96; 102539, 2024. doi.org/10.1016/j.flowmeasinst.2024.102539

    23-24   Arash Ahmadi, Amir H. Azimi, Effects of ramp slope and discharge on hydraulic performance of submerged hump weirs, Flow Measurement and Instrumentation, 96; 102520, 2024. doi.org/10.1016/j.flowmeasinst.2023.102520

    20-24   Parisa Mirkhorli, Amir Ghaderi, Forough Alizadeh Sanami, Mirali Mohammadi, Alban Kuriqi, An investigation on hydraulic aspects of rectangular labyrinth pool and weir fishway using FLOW-3D, Arabian Journal for Science and Engineering, 2024. doi.org/10.1007/s13369-023-08537-7

    17-24   Veysi Kartal, M. Emin Emiroglu, Numerical simulation of the flow passing through the side weir-gate, Flow Measurement and Instrumentation, 95; 102519, 2024. doi.org/10.1016/j.flowmeasinst.2023.102519

    16-24   Junqi Chen, Wen Zhang, Chen Cao, Han Yin, Jia Wang, Wankun Li, Yanhao Zheng, The effect of the check dam on the sediment transport and control in debris flow events, Engineering Geology, 329; 107397, 2024. doi.org/10.1016/j.enggeo.2023.107397

    15-24   Jingxin Mao, Yijun Wang, Hao Zhang, Xiaofei Jing, Study on the influence of urban water supply pipeline leakage on the scouring failure law of cohesive soil subgrade, Water, 16.1; 93, 2024. doi.org/10.3390/w16010093

    13-24   Ramtin Sabeti, Mohammad Heidarzadeh, Alessandro Romano, Gabriel Barajas Ojeda, Javier L. Lara, Three-dimensional simulations of subaerial landslide-generated wave: comparing OpenFOAM and FLOW-3D HYDRO models, Pure and Applied Geophysics, 2024. doi.org/10.1007/s00024-024-03443-x

    12-24   Damoon Mohammad Ali Nezhadian, Hossein Hamidifar, Effects of floating debris on flow characteristics around slotted bridge piers: a numerical simulation, Water, 16.1; 90, 2024. doi.org/10.3390/w16010090

    10-24   Zhong Gao, Jinpeng Liu, Wen He, Bokai Lu, Manman Wang, Zikai Tang, Study of a tailings dam failure pattern and post-failure effects under flooding conditions, Water, 16.1; 68, 2024. doi.org/10.3390/w16010068

    9-24   Yilin Yang, Jinzhao Li, Waner Zou, Benshuang Chen, Numerical investigation of flow and scour around complex bridge piers in wind-wave-current conditions, Journal of Marine Science and Engineering, 12.1; 23, 2024. doi.org/10.3390/jmse12010023

    7-24   Penfeng Li, Haixiao Jing, Guodong Li, Generation and prediction of water waves induced by rigid piston-like landslide, Natural Hazards, 120; pp. 2683-2704, 2024. doi.org/10.1007/s11069-023-06300-7

    6-24   Jie-yuan Zhang, Xing-Guo Yang, Gang Fan, Hai-bo Li, Jia-wen Zhou, Physical and numerical modeling of a landslide dam breach and flood routing process, Journal of Hydrology, 628; 130552, 2024. doi.org/10.1016/j.jhydrol.2023.130552

    241-23 Kamyab Habibi, Farinaz Erfani Fard, Seyed Amin Asghari Pari, Investigation of the flow field around bridge piers on a non-eroding bed using FLOW-3D, 22nd Iranian Conference on Hydraulics, 2023.

    240-23 Dong Hyun Kim, Su-Hyun Yang, Sung Sik Joo, Seung Oh Lee, Analysis of flow velocity in the channel according to the type of revetments blocks using 3D numerical model, Journal of Korean Society of Disaster and Security, 16.4; pp. 9-18, 2023.

    238-23 Mohamed Elberry, Abdelazim Ali, Fahmy Abdelhaleem, Amir Ibrahim, Numerical investigations of stilling basin efficiency downstream radial gates – A case study of New Assuit Barrage, Egypt, Journal of Water and Land Development, 59 (X-XII); pp. 126-134, 2023. doi.org/10.24425/jwld.2023.147237

    237-23 Oğuzhan Uluyurt, Numerical investigation of energy dissipation using macro roughness elements in a stilling basin, Thesis, Middle East Technical University, 2023.

    236-23   Mohamed Galal Eltarabily, Mohamed Kamel Elshaarawy, Mohamed Elkiki, Tarek Selim, Computational fluid dynamics and artificial neural networks for modelling lined irrigation canals with low-density polyethylene and cement concrete liners, Irrigation and Drainage, 2023. doi.org/10.1002/ird.2911

    234-23   Saman Baharvand, Babak Lashkar-Ara, Hydrodynamic and biological assessment of modified meander C-type fishway to pass rainbow trout (Oncorhynchus mykiss) fish species, Scientia Iranica, 2023.

    232-23   Chung R. Song, Richard L. Wood, Basil Abualshar, Bashar Al-Nimri, Mark O’Brien, Mitra Nasimi, Erosion resistant rock shoulder, Nebraska Department of Transportation, Final Report SPR-P1(20), 2023.

    230-23   Rongzhao Zhang, Wen Xiong, Xiaolong Ma, C.S. Cai, A forensic investigation of progressive bridge collapse under floods and asymmetric scour validated by incident video footages, Structure and Infrastructure Engineering, 2023. doi.org/10.1080/15732479.2023.2290701

    229-23   Vivek Sharma Jai, Hydraulic simulation and numerical investigation of the flow in the stepped spillway with the help of FLOW-3D software, International Journal of Innovative Science and Research Technology, 8; 2023. doi.org/10.5281/zenodo.8076943

    228-23   Hao Chen, Yang Tang, Jinyuan Li, Faxin Zhu, Xianbin Teng, The influence of impinging distance variable on the effect of submerged jet scour, Journal of Physics: Conference Series, 2660; 012004, 2023. doi.org/10.1088/1742-6596/2660/1/012004

    225-23   Kyle Thomson, Towards safer bridges: Overcoming 2D model limitations and reducing flood risks through computational fluid dynamics, IPWEA Annual Conference Gold Coast, 2023.

    223-23   Chong-xun Wang, Jia-wen Zhou, Chang-bing Zhang, Yu-xiang Hu, Hao Chen, Hai-bo Li, Failure mechanism analysis and mass movement assessment of a post‑earthquake high slope, Arabian Journal of Geosciences, 16; 683, 2023. doi.org/10.1007/s12517-023-11737-y

    222-23   Alaa Ghzayel, Anthony Beaudoin, Sébastien Jarny, Three-dimensional numerical study of a local scour downstream of a submerged sluice gate using two hydro-morphodynamic models, SedFoam and FLOW-3D, Comptes Rendus. Mécanique, 351.G2; pp. 525-550, 2023. doi.org/10.5802/crmeca.223

    221-23   Othon José Rocha, Luiz Renato Martini Filho, Caio Gripp Benevente, Letícia Imbuzeiro, Modelagem CFD-3D aplicada ao setor de mineração (3D CFD modeling applied to the mining sector), 34th Seminario Nacional de Grandes Barragens, 2023.

    220-23   Gaetano Crispino, David Dorthe, Corrado Gisonni, Michael Pfister, Optimal hydraulic design of supercritical bend manholes, Proceedings of the 40th IAHR World Congress, Eds. Helmut Habersack, Michael Tritthart, Lisa Waldenberger, 2023. doi.org/10.3850/978-90-833476-1-5_iahr40wc-p0090-cd

    218-23   Arun Goel, Aditya Thakare, M.K. Verma, M.Z. Qamar, Evaluation of design approaches of desilting basins for hydroelectric projects in Himalayan region, ISH Journal of Hydraulic Engineering, 30.1; pp. 122-131, 2023. doi.org/10.1080/09715010.2023.2283593

    215-23   Ahmed Ashour, Emam Salah, Numerical study of energy dissipation in baffled stepped spillway using FLOW-3D, International Journal of Research in Engineering, Science and Management, 6.11; 2023.

    214-23   Farshid Mosaddeghi, Mete Koken, Ismail Aydin, Finite volume analysis of dam breaking subjected to earthquake accelerations, Journal of Hydraulic Research, 61.6; pp. 845-865, 2023. doi.org/10.1080/00221686.2023.2259858

    213-23   Habib Ahmari, Ashish Bhurtyal, Srinivas Prabakar, Qazi Ashique Mowla, Saman Baharvand, Hassan Alsaud, Laboratory testing of engineered media for biofiltration swales, University of Texas Arlington, Project No. TRN6835 Final Report, 2023.

    209-23   Cong Trieu Tran, Cong Ty Trinh, Prediction of the vortex evolution and influence analysis of rough bed in a hydraulic jump with the Omega-Liutex method, Tehnički Vjesnik, 30.6; 2023. doi.org/10.17559/TV-20230206000327

    203-23   Muhammad Waqas Zaffar, Ishtiaq Hassan, Zulfiqar Ali, Kaleem Sarwar, Muhammad Hassan, Muhammad Taimoor Mustafa, Faizan Ahmed Waris, Numerical investigation of hydraulic jumps with USBR and wedge-shaped baffle block basins for lower tailwater, AQUA – Water Infrastructure, Ecosystems and Society, 72.11; 2081, 2023. doi.org/10.2166/aqua.2023.261

    201-23   E.F.R. Bollaert, Digital cloud-based platform to predict rock scour at high-head dams, Role of Dams and Reservoirs in a Successful Energy Transition, Eds. Robert Boes, Patrice Droz, Raphael Leroy, 2023. doi.org/10.1201/9781003440420

    200-23   Iacopo Vona, Oysters’ integration on submerged breakwaters as nature-based solution for coastal protection within estuarine environments, Thesis, University of Maryland, 2023.

    198-23   Hao Chen, Xianbin Teng, Zhibin Zhang, Faxin Zhu, Jie Wang, Zhaohao Zhang, Numerical analysis of the influence of the impinging distance on the scouring efficiency of submerged jets, Fluid Dynamics & Materials Processing, 20.2; pp. 429-445, 2023. doi.org/10.32604/fdmp.2023.030585

    193-23   Chen Peng, Liuweikai Gu, Qiming Zhong, Numerical simulation of dam failure process based on FLOW-3D, Advances in Frontier Research on Engineering Structures, pp. 545-550, 2023. doi.org/10.3233/ATDE230245

    189-23   Rebecca G. Englert, Age J. Vellinga, Matthieu J.B. Cartigny, Michael A. Clare, Joris T. Eggenhuisen, Stephen M. Hubbard, Controls on upstream-migrating bed forms in sandy submarine channels, Geology, 51.12; PP. 1137-1142, 2023. doi.org/10.1130/G51385.1

    187-23   J.W. Kim, S.B. Woo, A numerical approach to the treatment of submerged water exchange processes through the sluice gates of a tidal power plant, Renewable Energy, 219.1; 119408, 2023. doi.org/10.1016/j.renene.2023.119408

    186-23   Chan Jin Jeong, Hyung Jun Park, Hyung Suk Kim, Seung Oh Lee, Study on fish-friendly flow characteristic in stepped fishway, Proceedings of the Korean Water Resources Association Conference, 2023. (In Korean)

    185-23   Jaehwan Yoo, Sedong Jang, Byunghyun Kim, Analysis of coastal city flooding in 2D and 3D considering extreme conditions and climate change, Proceedings of the Korean Water Resources Association Conference, 2023. (In Korean)

    180-23   Prathyush Nallamothu, Jonathan Gregory, Jordan Leh, Daniel P. Zielinski, Jesse L. Eickholt, Semi-automated inquiry of fish launch angle and speed for hazard analysis, Fishes, 8.10; 476, 2023. doi.org/10.3390/fishes8100476

    179-23   Reza Norouzi, Parisa Ebadzadeh, Veli Sume, Rasoul Daneshfaraz, Upstream vortices of a sluice gate: an experimental and numerical study, AQUA – Water Infrastructure, Ecosystems and Society, 72.10; 1906, 2023. doi.org/10.2166/aqua.2023.269

    178-23   Bai Hao Li, How Tion Puay, Muhammad Azfar Bin Hamidi, Influence of spur dike’s angle on sand bar formation in a rectangular channel, IOP Conference Series: Earth and Environmental Science, 1238; 012027, 2023. doi.org/10.1088/1755-1315/1238/1/012027

    177-23   Hao Zhe Khor, How Tion Puay, Influence of gate lip angle on downpull forces for vertical lift gates, IOP Conference Series: Earth and Environmental Science, 1238; 012019, 2023. doi.org/10.1088/1755-1315/1238/1/012019

    175-23   Juan Francisco Macián-Pérez, Rafael García-Bartual, P. Amparo López-Jiménez, Francisco José Vallés-Morán, Numerical modeling of hydraulic jumps at negative steps to improve energy dissipation in stilling basins, Applied Water Science, 13.203; 2023. doi.org/10.1007/s13201-023-01985-4

    174-23   Ahintha Kandamby, Dusty Myers, Narrows bypass chute CFD analysis, Dam Safety, 2023.

    173-23   H. Jalili, R.C. Mahon, M.F. Martinez, J.W. Nicklow, Sediment sluicing from the reservoirs with high efficiency, SEDHYD, 2023.

    170-23   Ramith Fernando, Gangfu Zhang, Beyond 2D: Unravelling bridge hydraulics with CFD modelling, 24th Queensland Water Symposium, 2023.

    169-23   K. Licht, G. Lončar, H. Posavčić, I. Halkijević, Short-time numerical simulation of ultrasonically assisted electrochemical removal of strontium from water, 18th International Conference on Environmental Science and Technology (CEST), 2023.

    166-23   Ebrahim Hamid Hussein Al-Qadami, Mohd Adib Mohammad Razi, Wawan Septiawan Damanik, Zahiraniza Mustaffa, Eduardo Martinez-Gomariz, Fang Yenn Teo, Anwar Ameen Hezam Saeed, Understanding the stability of passenger vehicles exposed to water flows through 3D CFD modelling, Sustainability, 15.17; 13262, 2023. doi.org/10.3390/su151713262

    165-23   Ebrahim Hamid Hussein Al-Qadami, Mohd Adib Mohammad Razi, Wawan Septiawan Damanik, Zahiraniza Mustaffa, Eduardo Martinez-Gomariz, Fang Yenn Teo, Anwar Ameen Hezam Saeed, 3-dimensional numerical study on the critical orientation of the flooded passenger vehicles, Engineering Letters, 31.3; 2023.

    159-23 Ruosi Zha, Weiwen Zhao, Decheng Wan, Numerical study of wave-ice floe interactions and overwash by a meshfree particle method, Ocean Engineering, 286.2; 115681, 2023. doi.org/10.1016/j.oceaneng.2023.115681

    157-23 Hamidreza Abbaszadeh, Kiyoumars Roushangar, Zahra Salahpour, Theoretical and numerical investigation of the sluice and radial gates discharge coefficient in the conditions of sill application, Iranian Journal of Irrigation and Drainage, 2023.

    155-23 Ting Zhang, Qunwei Dai, Dejun An, R. Agustin Mors, Qiongfang Li, Ricardo A. Astini, Jingwen He, Jie Cui, Ruiyang Jiang, Faqin Dong, Zheng Dang, Effective mechanisms in the formation of pool-rimstone dams in continental carbonate systems: The case study of Huanglong, China, Sedimentary Geology, 455; 106486, 2023. doi.org/10.1016/j.sedgeo.2023.106486

    153-23 Jyh-Haw Tang, Aisyah Puspasari, Numerical simulation of scouring around four cylindrical piles with different inclination angles arrangements, Proceedings of the 4th International Conference on Advanced Engineering and Technology (ICATECH), 1; pp. 139-145, 2023. doi.org/10.5220/0012115500003680

    152-23 Yasser El-Saie, Osama Saleh, Marihan El-Sayed, Abdelazim Ali, Eslam El-Tohamy, Yasser Mohamed Sadek, Dissipation of water energy by using a special stilling basin via three-dimensional numerical model, The Open Civil Engineering Journal, 17; 2023.

    150-23 Shelby J. Koldewyn, Using computational fluid dynamics for predicting hydraulic performance of arced labyrinth weirs, Thesis, Utah State University, 2023.

    146-23 Lav Kumar Gupta, Manish Pandey, P. Anand Raj, Numerical modeling of scour and erosion processes around spur dike, CLEAN Soil Air Water, 2023. doi.org/10.1002/clen.202300135

    145-23 Nariman Mehranfar, Morteza Kolahdoozan, Shervin Faghihirad, Development of multiphase solver for the modeling of turbidity currents (the case study of Dez Dam), International Journal of Multiphase Flow, 168; 104586, 2023. doi.org/10.1016/j.ijmultiphaseflow.2023.104586

    143-23 Fei Ma, Lei You, Jin Liu, Estimation in jet deflection angle of deflector on the chutes, ISH Journal of Hydraulic Engineering, 2023. doi.org/10.1080/09715010.2023.2241416

    142-23 Ali Emre Ulu, M. Cihan Aydin, Fevzi Önen, Energy dissipation potentials of grouped spur dikes in an open channel, Water Resources Management, 37; pp. 4491-4506, 2023. doi.org/10.1007/s11269-023-03571-4

    141-23 Haofei Feng, Shengtao Du, David Z. Zhu, Numerical study of effects of flushing gate height and sediment bed properties on cleaning efficiency in a simplified self-cleaning device, Water Science & Technology, 88.3; pp. 542-555, 2023. doi.org/10.2166/wst.2023.245

    140-23 Brian Fox, 3D CFD modeling with FLOW-3D HYDRO, Proceedings, SEDHYD, 2023.

    139-23 Masoumeh (Negar) Ghahramani, Improved empirical and numerical predictive modelling of potential tailings dam breaches and their downstream impacts, Thesis, The University of British Columbia, 2023.

    138-23 Rui-Tao Yin, Bing Zhu, Shuai-Wei Yuan, Jun-Nan Li, Zhen-Yu Yang, Zhi-Ying Yang, Dynamic analyses of long-span cable-stayed and suspension cooperative system bridge under combined actions of wind and regular wave loads, Applied Ocean Research, 138; 103683, 2023. doi.org/10.1016/j.apor.2023.103683

    137-23 Xuefeng Chen, Shikang Liu, Yuanming Wang, Yuetong Hao, Kefeng Li, Hongtao Wang, Ruifeng Liang, Restoration of a fish-attracting flow field downstream of a dam based on the swimming ability of endemic fishes: A case study in the upper Yangtze River basin, Journal of Environmental Management, 345; 118694, 2023. doi.org/10.1016/j.jenvman.2023.118694

    135-23 Nelson Cely Calixto, Melquisedec Cortés Zambrano, Alberto Galvis Castaño, Gustavo Carrillo Soto, Analysis of a three-dimensional numerical modeling approach for predicting scour processes in longitudinal walls of granular bedding rivers, EUREKA: Physics and Engineering, 4; 2023. doi.org/10.21303/2461-4262.2023.002682

    134-23 Tarek Selim, Abdelrahman Kamal Hamed, Mohamed Elkiki, Mohamed Galal Eltarabily, Numerical investigation of flow characteristics and energy dissipation over piano key and trapezoidal labyrinth weirs under free-flow conditions, Modeling Earth Systems and Environment, 2023. doi.org/10.1007/s40808-023-01844-w

    132-23 Gang Lei, Hongbao Huang, Xiongan Fan, Junan Su, Qingxiang Wang, Xiaoliang Wang, Kai Peng, Jianmin Zhang, Influence of the transition section shape on the cavitation characteristics of the bottom outlet, Water Supply, 23.8; pp. 3061-3077, 2023. doi.org/10.2166/ws.2023.181

    129-23 Rasoul Daneshfaraz, Reza Norouzi, John Patrick Abraham, Parisa Ebadzadeh, Behnaz Akhondi, Maryam Abar, Determination of flow characteristics over sharp-crested triangular plan form weirs using numerical simulation, Water Science, 37.1; 2023. doi.org/10.1080/23570008.2023.2236384

    124-23 Imad Habeeb Obead, Ahmed Rahim Sahib, Mathematical models for simulating the hydraulic behavior of flow deflectors: laboratory and CFD-based study, Innovative Infrastructure Solutions, 8; 213, 2023. doi.org/10.1007/s41062-023-01170-1

    120-23 Kwang-Su Kim, Jong-Song Jo, Improving the power output estimation for a tidal power plant: a case study, Energy, 2023. doi.org/10.1680/jener.23.00007

    119-23 Hanif Pourshahbaz, Tadros Ghobrial, Ahmad Shakibaeinia, Evaluating a CFD model for three-dimensional simulation of ice structure interaction, CGU HS Committee on River Ice Processes and the Environment (CRIPE), 22nd Workshop on the Hydraulics of Ice-Covered Rivers, 2023.

    118-23 Sruthi T. Kalathil, Venu Chandra, Experimental and numerical investigation on the hydraulic design criteria for a step-pool nature-like fishway, Progress in Physical Geography: Earth and Environment, 2023. doi.org/10.1177/03091333231187619

    117-23 Lav Kumar Gupta, Manish Pandey, P. Anand Raj, Numerical simulation of local scour around the pier with and without airfoil collar (AFC) using FLOW-3D, Environmental Fluid Mechanics, 2023. doi.org/10.1007/s10652-023-09932-2

    116-23 Paolo Peruzzo, Matteo Cappozzo, Nicola Durighetto, Gianluca Botter, Local processes with a global impact: unraveling the dynamics of gas evasion in a step-and-pool configuration, Biogeosciences, 20; pp. 3261-3271, 2023. doi.org/10.5194/bg-20-3261-2023

    114-23 Muhammad Waqas Zaffar, Ishtiaq Hassan, Numerical investigation of hydraulic jump for different stilling basins using FLOW-3D, AQUA – Water Infrastructure, Ecosystems and Society, 72.7; pp. 1320-1343, 2023. doi.org/10.2166/aqua.2023.290

    112-23 J. Chandrashekhar Iyer, E.J. James, Indispensability of model studies in the design of settling basins of hydropower projects in river basins with high sediment yield, Fluid Mechanics and Hydraulics, pp. 367-381, 2023. doi.org/10.1007/978-981-19-9151-6_30

    110-23 Ehsan Afaridegan, Nosratollah Amanian, Abbas Parsaie, Amin Gharehbaghi, Hydraulic investigation of modified semi-cylindrical weirs, Flow Measurement and Instrumentation, 93; 102405, 2023. doi.org/10.1016/j.flowmeasinst.2023.102405

    103-23 Jin Yang, Weqiang Su, Binhua Li, Calculation of natural alluvial separation of sandy tailings slurry based on FLOW-3D, Mechanics in Engineering, 45.3; pp. 559-564, 2023.

    101-23 Tutku Ezgi Yönter, Modeling of river flow and flow dynamics near junctions, Thesis, Middle East Technical University, 2023.

    99-23 Mohammad Sadeghpour, Mohammad Vaghefi, Seyed Hamed Meraji, Artificial roughness dimensions and their influence on bed topography variations downstream of a culvert: An experimental study, Water Resources Management, 37; pp. 4143-4157, 2023. doi.org/10.1007/s11269-023-03543-8

    98-23 M. Aksel, Numerical analysis of the flow structure around inclined solid cylinder and its effect on bed shear stress distribution, Journal of Applied Fluid Mechanics, 16.8; pp. 1627-1639, 2023. doi.org/10.47176/jafm.16.08.1697

    96-23 Waqed H. Hassan, Nidaa Ali Shabat, Numerical investigation of the optimum angle for open channel junction, Civil Engineering Journal, 9.5; 2023. doi.org/10.28991/CEJ-2023-09-05-07

    94-23 Emad Khanahmadi, Amir Ahmad Dehghani, Seyed Nasrollah Alenabi, Navid Dehghani, Edward Barry, Hydraulic of curved type-B piano key weirs characteristics under free flow conditions, Modeling Earth Systems and Environment, 2023. doi.org/10.1007/s40808-023-01790-7

    93-23 Laura-Louise Alicke, Improved priming of a siphon spillway with the use of a flexible membrane researched through numerical modeling, Thesis, Idaho State University, 2023.

    91-23 Wahidullah Hakim Safi, Pranab K. Mohapatra, Flow past: An artificial channel confluence with mobile bed, World Environmental and Water Resources Congress, 2023. doi.org/10.1061/9780784484852.023

    86-23 Ghasem Aghashirmohammadi, Mohammad Heidarnejad, Mohammad Hossein Purmohammadi, Alireza Masjedi, Experimental and numerical study the effect of flow splitters on trapezoidal and triangular labyrinth weirs, Water Science, 37.1; 2023. doi.org/10.1080/23570008.2023.2210391

    84-23 Nikolaos Xafoulis, Evangelia Farsirotou, Spyridon Kotsopoulos, Three-dimensional computational flow dynamics analysis of free-surface flow in a converging channel, Energy Systems, 2023. doi.org/10.1007/s12667-023-00575-2

    83-23 Navid Zarrabi, Mohammad Navid Moghim, Mohammad Reza Eftakhar, A semi-analytical study of fiber reinforced concrete abrasion-erosion through water-borne sand-jet flow in hydraulic structures, Tribology International, 185; 108568, 2023. doi.org/10.1016/j.triboint.2023.108568

    82-23 Somayyeh Saffar, Abbas Safaei, Farnoush Aghaee Daneshvar, Mohsen Solimani Babarsad, FLOW-3D numerical modeling of converged side weir, Iranian Journal of Science and Technology: Transactions of Civil Engineering, 2023. doi.org/10.1007/s40996-023-01077-y

    79-23 Wangshu Wei, Optimization of the mixing in a produced water storage tank using CFD, World Environmental and Water Resources Congress, Eds. Sajjad Ahmad, Regan Murray, 2023. doi.org/10.1061/9780784484852

    77-23   Paolo Peruzzo, Matteo Cappozzo, Nicola Durighetto, Gianluca Botter, Local processes with global impact: unraveling the dynamics of gas evasion in a step-and-pool configuration, Biogeosciences, 2023. doi.org/10.5194/bg-2023-68

    74-23   Kaywan Othman Ahmed, Nazim Nariman, Dara Muhammad Hawez, Ozgur Kisi, Ata Amini, Predicting and optimizing the influenced parameters for culvert outlet scouring utilizing coupled FLOW 3D-surrogate modeling, Iranian Journal of Science and Technology: Transactions of Civil Engineering, 47; pp. 1763-1776, 2023. doi.org/10.1007/s40996-023-01096-9

    73-23   Ashkan Pilbala, Mahmood Shafai Bejestan, Seyed Mohsen Sajjadi, Luigi Fraccarollo, Investigation of the different models of elliptical-Lopac gate performance under submerged flow conditions, Water Resources Management, 2023. doi.org/10.1007/s11269-023-03512-1

    69-23   Chonoor Abdi Chooplou, Masoud Ghodsian, Davoud Abediakbar, Aram Ghafouri, An experimental and numerical study on the flow field and scour downstream of rectangular piano key weirs with crest indentations, Innovative Infrastructure Solutions, 8; 140, 2023. doi.org/10.1007/s41062-023-01108-7

    68-23   Mahmood Shafai Bajestan, Mostafa Adineh, Hesam Ghodousi, Numerical modeling of sediment washing (flushing) in dams (Case study of Sefidrood dam), Journal of Irrigation Sciences and Engineering, 2023.

    65-23   Charles R. Ortloff, CFD investigations of water supply and distribution systems of ancient old and new world archaeological sites to recover ancient water engineering technologies, Water, 15.7; 1363, 2023. doi.org/10.3390/w15071363

    63-23   Rasoul Daneshfaraz, Reza Norouzi, Parisa Ebadzadeh, Alban Kuriqi, Effect of geometric shapes of chimney weir on discharge coefficient, Journal of Applied Water Engineering and Research, 2023. doi.org/10.1080/23249676.2023.2192977

    59-23   Hongbo Mi, Chuan Wang, Xuanwen Jia, Bo Hu, Hongliang Wang, Hui Wang, Yong Zhu, Hydraulic characteristics of continuous submerged jet impinging on a wall by using numerical simulation and PIV experiment, Sustainability, 15.6; 5159, 2023. doi.org/10.3390/su15065159

    58-23   O.P. Maurya, K.K. Nandi, S. Modalavalasa, S. Dutta, Flow hydrodynamics influences due to flood plain sand mining in a meandering channel, Sustainable Environment (NERC 2022), Eds. D. Deka, S.K. Majumder, M.K., Purkait, 2023. doi.org/10.1007/978-981-19-8464-8_16

    57-23   Harshvardhan Harshvardhan, Deo Raj Kaushal, CFD modelling of local scour and flow field around isolated and in-line bridge piers using FLOW-3D, EGU General Assembly, EGU23-3820, 2023. doi.org/10.5194/egusphere-egu23-3820

    54-23   Reza Nematzadeh, Gholam-Abbas Barani, Ehsan Fadaei-Kermani, Numerical investigation of bed-load changes on sediment flushing cavity, Journal of Hydraulic Structures, 4; 2023. doi.org/10.22055/jhs.2023.42542.1237

    53-23   Rasoul Daneshfaraz, Reza Norouzi, Parisa Ebadzadeh, Alban Kuriqi, Influence of sill integration in labyrinth sluice gate hydraulic performance, Innovative Infrastructure Solutions, 8.118; 2023. doi.org/10.1007/s41062-023-01083-z

    52-23   Shu Jiang, Yutong Hua, Mengxing He, Ying-Tien Lin, Biyun Sheng, Effect of a circular cylinder on hydrodynamic characteristics over a strongly curved channel, Sustainability, 15.6; 4890, 2023. doi.org/10.3390/su15064890

    51-23   Ehsan Aminvash, Kiyoumars Roushangar, Numerical investigation of the effect of the frontal slope of simple and blocky stepped spillway with sem-circular crest on its hydraulic parameters, Iranian Journal of Irrigation and Drainage, 17.1; pp. 102-116, 2023.

    50-23   Shizhuang Chen, Anchi Shi, Weiya Xu, Long Yan, Huanling Wang, Lei Tian, Wei-Chau Xie, Numerical investigation of landslide-induced waves: a case study of Wangjiashan landslide in Baihetan Reservoir, China, Bulletin of Engineering Geology and the Environment, 82.110; 2023. doi.org/10.1007/s10064-023-03148-w

    49-23   Jiří Procházka, Modelling flow distribution in inlet galleries, VTEI, 1; 2023. doi.org/10.46555/VTEI.2022.11.002

    47-23   M. Cihan Aydin, Ali Emre Ulu, Numerical investigation of labyrinth‑shaft spillway, Applied Water Science, 13.89; 2023. doi.org/10.1007/s13201-023-01896-4

    46-23   Guangwei Lu, Jinxin Liu, Zhixian Cao, Youwei Li, Xueting Lei, Ying Li, A computational study of 3D flow structure in two consecutive bends subject to the influence of tributary inflow in the middle Yangtze River, Engineering Applications of Computational Fluid Mechanics, 17.1; 2183901, 2023. doi.org/10.1080/19942060.2023.2183901

    44-23   Xun Huang, Zhijian Zhang, Guoping Xiang, Sensitivity analysis of a built environment exposed to the synthetic monophasic viscous debris flow impacts with 3-D numerical simulations, Natural Hazards and Earth Systems Sciences, 23; pp. 871-889, 2023. doi.org/10.5194/nhess-23-871-2023

    43-23   Yisheng Zhang, Jiangfei Wang, Qi Zhou, Haisong Li, Wei Tang, Investigation of the reduction of sediment deposition and river flow resistance around dimpled surface piers, Environmental Science and Pollution Research, 2023. doi.org/10.1007/s11356-023-26034-0

    41-23   Nejib Hassen Abdullahi, Zulfequar Ahmad, Experimental and CFD studies on the flow field and bed morphology in the vicinity of a sediment mining pit, EGU General Assembly, 2023. doi.org/10.5194/egusphere-egu23-446

    40-23   Seonghyeon Ju, Jongchan Yi, Junho Lee, Jiyoon Kim, Chaehwi Lim, Jihoon Lee, Kyungtae Kim, Yeojoon Yoon, High-efficiency microplastic sampling device improved using CFD analysis, Sustainability, 15.5; 3907, 2023. doi.org/10.3390/su15053907

    37-23   Muhammad Waqas Zaffar, Ishtiaq Hassan, Hydraulic investigation of stilling basins of the barrage before and after remodelling using FLOW-3D, Water Supply, 23.2; pp. 796-820, 2023. doi.org/10.2166/ws.2023.032

    35-23   Mehmet Cihan, Ali Emre Ulu, Developing and testing a novel pressure-controlled hydraulic profile for siphon-shaft spillways, Flow Measurement and Instrumentation, 90; 102332, 2023. doi.org/10.1016/j.flowmeasinst.2023.102332

    28-23   Yuhan Li, Deshen Chen, Yan Zhang, Hongliang Qian, Jiangyang Pan, Yinghan Huang, Boo Cheong Khoo, Thermal structure and hydrodynamic analysis for a new type of flexible temperature-control curtain, Journal of Hydrology, 618; 129170, 2023. doi.org/10.1016/j.jhydrol.2023.129170

    22-23   Rong Lu, Wei Jiang, Jingjing Xiao, Dongdong Yuan, Yupeng Li, Yukai Hou, Congcong Liu, Evaluation of moisture migration characteristics of permeable asphalt pavement: Field research, Journal of Environmental Management, 330; 117176, 2023. doi.org/10.1016/j.jenvman.2022.117176

    18-23   Thu Hien-T. Le, Van Chien Nguyen, Cong Phuc Dang, Thanh Thin-T. Nguyen, Bach Quynh-T. Pham, Ngoc Thoa Le, Numerical assessment on hydraulic safety of existing conveyance structures, Modeling Earth Systems and Environment, 2023. doi.org/10.1007/s40808-022-01685-z

    17-23   Meysam Nouri, Parveen Sihag, Ozgur Kisi, Mohammad Hemmati, Shamsuddin Shahid, Rana Muhammad Adnan, Prediction of the discharge coefficient in compound broad-crested weir gate by supervised data mining techniques, Sustainability, 15.1; 433, 2023. doi.org/10.3390/su15010433

    16-23   Mohammad Bananmah, Mohammad Reza Nikoo, Mehrdad Ghorbani Mooselu, Amir H. Gandomi, Optimum design of the chute-flip bucket system using evolutionary algorithms considering conflicts between decision-makers, Expert Systems with Applications, 216; 119480, 2023. doi.org/10.1016/j.eswa.2022.119480

    13-23   Xiaoyu Yi, Wenkai Feng, Botao Li, Baoguo Yin, Xiujun Dong, Chunlei Xin, Mingtang Wu, Deformation characteristics, mechanisms, and potential impulse wave assessment of the Wulipo landslide in the Baihetan reservoir region, China, Landslides, 20; pp. 615-628, 2023. doi.org/10.1007/s10346-022-02010-6

    11-23 Şebnem Elçi, Oğuz Hazar, Nisa Bahadıroğlu, Derya Karakaya, Aslı Bor, Destratification of thermally stratified water columns by air diffusers, Journal of Hydro-environment Research, 46; pp. 44-59, 2023. doi.org/10.1016/j.jher.2022.12.001

    7-23 Shikang Liu, Yuxiang Jian, Pengcheng Li, Ruifeng Liang, Xuefeng Chen, Yunong Qin, Yuanming Wang, Kefeng Li, Optimization schemes to significantly improve the upstream migration of fish: A case study in the lower Yangtze River basin, Ecological Engineering, 186; 106838, 2023. doi.org/10.1016/j.ecoleng.2022.106838

    6-23 Maryam Shahabi, Javad Ahadiyan, Mehdi Ghomeshi, Marjan Narimousa, Christos Katopodis, Numerical study of the effect of a V-shaped weir on turbulence characteristics and velocity in V-weir fishways, River Research and Applications, 2023. doi.org/10.1002/rra.4064

    5-23 Muhammad Nur Aiman Bin Roslan, Hee Min Teh, Faris Ali Hamood Al-Towayti, Numerical simulations of wave diffraction around a low-crested semicircular breakwater, Proceedings of the 5th International Conference on Water Resources (ICWR), Lecture Notes in Civil Engineering, 293.1; pp. 421-433, 2023. doi.org/10.1007/978-981-19-5947-9_34

    4-23 V.K. Krishnasamy, M.H. Jamal, M.R. Haniffah, Modelling of wave runup and overtopping over Accropode II breakwater, Proceedings of the 5th International Conference on Water Resources (ICWR), Lecture Notes in Civil Engineering, 293.1; pp. 435-444, 2023. doi.org/10.1007/978-981-19-5947-9_35

    3-23 Anas S. Ghamam, Mohammed A. Abohatem, Mohd Ridza Bin Mohd Haniffah, Ilya K. Othman, The relationship between flow and pressure head of partially submerged orifice through CFD modelling using Flow-3D, Proceedings of the 5th International Conference on Water Resources (ICWR), Lecture Notes in Civil Engineering, 293.1; pp. 235-250, 2023. doi.org/10.1007/978-981-19-5947-9_20

    2-23 M.Y. Zainab, A.L.S. Zebedee, A.W. Ahmad Khairi, I. Zulhilmi, A. Shahabuddin, Modelling of an embankment failure using Flow-3D, Proceedings of the 5th International Conference on Water Resources (ICWR), Lecture Notes in Civil Engineering, 293.1; pp. 273-282, 2023. doi.org/10.1007/978-981-19-5947-9_23

    1-23 Gaetano Crispino, David Dorthe, Corrado Gisonni, Michael Pfister, Hydraulic capacity of bend manholes for supercritical flow, Journal of Irrigation and Drainage Engineering, 149.2; 2022. doi.org/10.1061/JIDEDH.IRENG-10014

    178-22 Greg Collecutt, Urs Baeumer, Shuang Gao, Bill Syme, Bridge deck afflux modelling — benchmarking of CFD and SWE codes to real-world data, Hydrology & Water Resources Symposium, 2022.

    177-22 Kyle Thomson, Mitchell Redenbach, Understanding cone fishway flow regimes with CFD, Hydrology & Water Resources Symposium, 2022.

    176-22 Kyle Thomson, Practical application of CFD for fish passage design, Hydrology & Water Resources Symposium, 2022.

    173-22 Melquisedec Cortés Zambrano, Helmer Edgardo Monroy González, Wilson Enrique Amaya Tequia, Three-dimensional numerical evaluation of hydraulic efficiency and discharge coefficient in grate inlets, Environmental Research, Engineering and Management, 78.4; 2022. doi.org/10.5755/j01.erem.78.4.31243

    168-22 Mohammad Javadi Rad, Pedram Eshaghieh Firoozbadi, Fatemeh Rostami, Numerical investigation of the effect dimensions of rectangular sedimentation tanks on its hydraulic efficiency using Flow-3D Software, Acta Technica Jaurinensis, 15.4; 2022. doi.org/10.14513/actatechjaur.00672

    165-22 Saman Mostafazadeh-Fard, Zohrab Samani, Dissipating culvert end design for erosion control using CFD platform FLOW-3D numerical simulation modeling, Journal of Pipeline Systems Engineering and Practice, 14.1; 2022. doi.org/10.1061/JPSEA2.PSENG-1373

    164-22 Mohammad Ahmadi, Alban Kuriqi, Hossein Mohammad Nezhad, Amir Ghaderi, Mirali Mohammadi, Innovative configuration of vertical slot fishway to enhance fish swimming conditions, Journal of Hydrodynamics, 34; pp. 917-933, 2022. doi.org/10.1007/s42241-022-0071-y

    160-22 Serife Yurdagul Kumcu, Kamil Ispir, Experimental and numerical modeling of various energy dissipator designs in chute channels, Applied Water Science, 12; 266, 2022. doi.org/10.1007/s13201-022-01792-3

    154-22 Usama Majeed, Najam us Saqib, Muhammad Akbar, Numerical analysis of energy dissipator options using computational fluid dynamics modeling — a case study of Mirani Dam, Arabian Journal of Geosciences, 15; 1614, 2022. doi.org/10.1007/s12517-022-10888-8

    151-22 Meibao Chen, Xiaofei Jing, Xiaohua Liu, Xuewei Huang, Wen Nie, Multiscale investigations of overtopping erosion in reinforced tailings dam induced by mud-water mixture overflow, Geofluids, 7209176, 2022. doi.org/10.1155/2022/7209176

    150-22   Daniel Damov, Francis Lepage, Michel Tremblay, Arian Cueto Bergner, Marc Villaneuve, Frank Scarcelli, Gord McPhail, Calabogie GS redevelopment—Capacity upgrade and hydraulic design, CDA Annual Conference, Proceedings, 2022.

    147-22   Hien T.T. Le, Chien Van Nguyen, Duc-Hau Le, Numerical study of sediment scour at meander flume outlet of boxed culvert diversion work, PLoS One, 17.9; e0275347, 2022. doi.org/10.1371/journal.pone.0275347

    140-22   Jackson Tellez-Alvarez, Manuel Gómez, Beniamino Russo, Numerical simulation of the hydraulic behavior of stepped stairs in a metro station, Advances in Hydroinformatics, Eds. P. Gourbesville, G. Caignaert, pp. 1001-1009, 2022. doi.org/10.1007/978-981-19-1600-7_62

    139-22   Juan Yu, Keyao Liu, Anbin Li, Mingfei Yang, Xiaodong Gao, Xining Zhao, Yaohui Cai, The effect of plug height and inflow rate on water flow characteristics in furrow irrigation, Agronomy, 12; 2225, 2022. doi.org/10.3390/agronomy12092225

    138-22   Nejib Hassen Abdullahi, Zulfequar Ahmad, Flow and morphological characteristics in mining pits of a river through numerical and experimental modeling, Modeling Earth Systems and Environment, 2022. doi.org/10.1007/s40808-022-01530-3

    137-22   Romain N.H.M. Van Mol, Christian Mörtl, Azin Amini, Sofia Siachou, Anton Schleiss, Giovanni De Cesare, Plunge pool scour and bank erosion: assessment of protection measures for Ilarion dam by physical and numerical modelling, HYDRO 2022, Proceedings, 27.02, 2022.

    136-22   Yong Cheng, Yude Song, Chunye Liu, Wene Wang, Xiaotao Hu, Numerical simulation research on the diversion characteristics of a trapezoidal channel, Water, 14.17; 2706, 2022. doi.org/10.3390/w14172706

    135-22   Zegao Yin, Yao Li, Jiahao Li, Zihan Zheng, Zihan Ni, Fuxiang Zheng, Experimental and numerical study on hydrodynamic characteristics of a breakwater with inclined perforated slots under regular waves, Ocean Engineering, 264; 112190, 2022. doi.org/10.1016/j.oceaneng.2022.112190

    133-22   Azin Amini, Martin Wickenhauser, Azad Koliji, Three-dimensional numerical modelling of Al-Salam storm water pumping station in Saudi Arabia, 39th IAHR World Congress, 2022. doi.org/10.3850/IAHR-39WC2521716X20221013

    131-22   Alireza Koshkonesh, Mohammad Daliri, Khuram Riaz, Fariba Ahmadi Dehrashid, Farhad Bahmanpouri, Silvia Di Francesco, Dam-break flow dynamics over a stepped channel with vegetation, Journal of Hydrology, 613.A; 128395, 2022. doi.org/10.1016/j.jhydrol.2022.128395

    129-22   Leona Repnik, Samuel Vorlet, Mona Seyfeddine, Asin Amini, Romain Dubuis, Giovanni De Cesare, Pierre Bourqui, Pierre-Adil Abdelmoula, Underground flow section modification below the new M3 Flon Metro station in Lausanne, Advances in Hydroinformatics, Eds. P. Gourbesville, G. Caignaert, pp. 979-999, 2022. doi.org/10.1007/978-981-19-1600-7_61

    127-22   Qin Panpan, Huang Bolin, Li Bin, Chen Xiaoting, Jiang Xiannian, Hazard analysis of landslide blocking a river in Guang’an Village, Wuxi County, Chongqing, China, Landslides, 2022. doi.org/10.1007/s10346-022-01943-2

    124-22   Vaishali P. Gadhe, S.R. Patnaik, M.R. Bhajantri, V.V. Bhosekar, Physical and numerical modeling of flow pattern near upstream guide wall of Jigaon Dam spillway, Maharashtra, River and Coastal Engineering, Water Science and Technology Library 117; pp. 237-247, 2022. doi.org/10.1007/978-3-031-05057-2_21

    123-22   M.Z. Qamar, M.K. Verma, A.P. Meshram, Neena Isaac, Numerical simulation of desilting chamber using Flow 3D, River and Coastal Engineering, Water Science and Technology Library 117; pp. 177-186, 2022. doi.org/10.1007/978-3-031-05057-2_16

    122-22   Abbas Parsaie, Saleh Jaafer Suleiman Shareef, Amir Hamzeh Haghiabi, Raad Hoobi Irzooki, Rasul M. Khalaf, Numerical simulation of flow on circular crested stepped spillway, Applied Water Science, 12; 215, 2022. doi.org/10.1007/s13201-022-01737-w

    121-22   Kazuki Kikuchi, Hajime Naruse, Morphological function of trace fossil Paleodictyon: An approach from fluid simulation, Paleontological Research, 26.4; pp. 378-389, 2022. doi.org/10.2517/PR210001

    120-22   Najam us Saqib, Muhammad Akbar, Huali Pan, Guoqiang Ou, Numerical investigation of pressure profiles and energy dissipation across the stepped spillway having curved treads using FLOW 3D, Arabian Journal of Geosciences, 15; 1363, 2022. doi.org/10.1007/s12517-022-10505-8

    116-22   Ayşegül Özgenç Aksoy, Mustafa Doğan, Semire Oğuzhan Güven, Görkem Tanır, Mehmet Şükrü Güney, Experimental and numerical investigation of the flood waves due to partial dam break, Iranian Journal of Science and Technology: Transactions of Civil Engineering, 2022. doi.org/10.1007/s40996-022-00919-5

    115-22   Abdol Mahdi Behroozi, Mohammad Vaghefi, Experimental and numerical study of the effect of zigzag crests with various geometries on the performance of A-type piano key weirs, Water Resources Management, 2022. doi.org/10.1007/s11269-022-03261-7

    114-22   Xun Huang, Zhijian Zhang, Guoping Xiang, Sensitivity analysis of a built environment exposed to debris flow impacts with 3-D numerical simulations, Natural Hazards and Earth Systems Sciences, 2022. doi.org/10.5194/nhess-2022-173

    113-22   Ahmad Ferdowsi, Mahdi Valikhan-Anaraki, Saeed Farzin, Sayed-Farhad Mousavi, A new combination approach for optimal design of sedimentation tanks based on hydrodynamic simulation model and machine learning algorithms, Physics and Chemistry of the Earth, 103201, 2022. doi.org/10.1016/j.pce.2022.103201

    103-22   Wangshu Wei, Optimization of the mixing in produced water (PW) retention tank with computational fluid dynamics (CFD) modeling, Produced Water Society Permian Basin, 2022.

    100-22   Michael Rasmussen, Using computational fluid dynamics to predict flow through the West Crack Breach of the Great Salt Lake railroad causeway, Thesis, Utah State University, 2022.

    99-22   Emad Khanahmadi, Amir Ahmad Dehghani, Mehdi Meftah Halaghi, Esmaeil Kordi, Farhad Bahmanpouri, Investigating the characteristic of hydraulic T-jump on rough bed based on experimental and numerical modeling, Modeling Earth Systems and Environment, 2022. doi.org/10.1007/s40808-022-01434-2

    97-22   Andrea Franco, A multidisciplinary approach for landslide-generated impulse wave assessment in natural mountain basins from a cascade analysis perspective, Thesis, University of Innsbruck, 2022.

    96-22   Geng Li, Binbin Wang, Simulation of the flow field and scour evolution by turbulent wall jets under a sluice gate, Journal of Hydro-environment Research, 43; pp. 22-32, 2022. doi.org/10.1016/j.jher.2022.06.002

    95-22   Philippe April LeQuéré, Ioan Nistor, Abdolmajid Mohammadian, Stefan Schimmels, Hydrodynamics and associated scour around a free-standing structure due to turbulent bores, Journal of Waterway, Port, Coastal, and Ocean Engineering, 148.5; 2022.

    94-22   Ramtin Sobhkhiz Foumani, Alireza Mardookhpour, Numerical simulation of geotechnical effects on local scour in inclined pier group with Flow-3D software, Water Resources Engineering Journal, 15.52; 2022. doi.org/10.30495/wej.2021.20404.2114

    92-22   Geng Li, Binbin Wang, Caroline M. Elliott, Bruce C.Call, Duane C. Chapman, Robert B. Jacobson, A three-dimensional Lagrangian particle tracking model for predicting transport of eggs of rheophilic-spawning carps in turbulent rivers, Ecological Modelling, 470; 110035, 2022. doi.org/10.1016/j.ecolmodel.2022.110035

    91-22   Ebrahim Hamid Hussein Al-Qadami, Zahiraniza Mustaffa, Mohamed Ezzat Al-Atroush, Eduardo Martinez-Gomariz, Fang Yenn Teo, Yasser El-Husseini, A numerical approach to understand the responses of passenger vehicles moving through floodwaters, Journal of Flood Risk Management, 2022. doi.org/10.1111/jfr3.12828

    90-22   Jafar Chabokpour, Hazi Md Azamathulla, Numerical simulation of pollution transport and hydrodynamic characteristics through the river confluence using FLOW 3D, Water Supply, 2022. doi.org/10.2166/ws.2022.237

    88-22   Michael Rasmussen, Som Dutta, Bethany T. Neilson, Brian Mark Crookston, CFD model of the density-driven bidirectional flows through the West Crack Breach in the Great Salt Lake causeway, Water, 13.17; 2423, 2022. doi.org/10.3390/w13172423

    84-22   M. Sobhi Alasta, Ahmed Shakir Ali Ali, Saman Ebrahimi, Muhammad Masood Ashiq, Abubaker Sami Dheyab, Adnan AlMasri, Anass Alqatanani, Mahdis Khorram, Modeling of local scour depth around bridge pier using FLOW 3D, CPRASE: Transactions of Civil and Environmental Engineering, 8.2; 2781, 2022.

    83-22   Mostafa Taherian, Seyed Ahmad Reza Saeidi Hosseini, Abdolmajid Mohammadian, Overview of outfall discharge modeling with a focus on turbulence modeling approaches, Advances in Fluid Mechanics: Modelling and Simulations, Eds. Dia Zeidan, Eric Goncalves Da Silva, Jochen Merker, Lucy T. Zhang, 2022.

    80-22   Soraya Naderi, Mehdi Daryaee, Seyed Mahmood Kashefipour, Mohammadreza Zayeri, Numerical and experimental study of flow pattern due to a plate installed upstream of orifice in pressurized flushing of dam reservoirs, Iranian Journal of Science and Technology: Transactions of Civil Engineering, 2022. doi.org/10.1007/s40996-022-00896-9

    79-22   Mahmood Nemati Qalee Maskan, Khosrow Hosseini, Effects of the simultaneous presence of bridge pier and abutment on the change of erodible bed using FLOW-3D, Journal of Iranian Water Engineering Research, 1.1; pp. 57-69, 2022. doi.org/10.22034/IJWER.2022.312074.1012

    75-22   Steven Matthew Klawitter, L-shaped spillway crest leg interface geometry impacts, Thesis, University of Colorado at Denver, 2022.

    72-22   Md. Mukdiul Islam, Md. Samiun Basir, Badal Mahalder, Local scour analysis around single pier and group of piers in tandem arrangement using FLOW 3D, 6th International Conference on Civil Engineering for Sustainable Development (ICCESD 2022), Khulna, Bangladesh, February 10-12, 2022.

    69-22   Kuo-Wei Liao, Zhen-Zhi Wang, Investigation of air-bubble screen on reducing scour in river facility, EGU General Assembly, EGU22-1137, 2022. doi.org/10.5194/egusphere-egu22-1137

    68-22   Cüneyt Yavuz, Energy dissipation scale for dam prototypes, ADYU Mühendislik Bilimleri Dergisi (Adıyaman University Journal of Engineering Sciences), 16; pp. 105-116, 2022.

    66-22   Ji-jian Lian, Shu-guang Zhang, Jun-ling He, An improved numerical model of ski-jump flood discharge atomization, Journal of Mountain Science, 19; pp. 1263-1273, 2022. doi.org/10.1007/s11629-021-7158-8

    62-22   Ali Montazeri, Amirabbas Abedini, Milad Aminzadeh, Numerical investigation of pollution transport around a single non-submerged spur dike, Journal of Contaminant Hydrology, 248; 104018, 2022. doi.org/10.1016/j.jconhyd.2022.104018

    61-22   Junhao Zhang, Yining Sun, Zhixian Cao, Ji Li, Flow structure at reservoir-tributary confluence with high sediment load, EGU General Assembly, Vienna, Austria, May 23-27, 2022. doi.org/10.5194/egusphere-egu22-1419

    60-22   S. Modalavalasa, V. Chembolu, V. Kulkarni, S. Dutta, Numerical and experimental investigation of effect of green river corridor on main channel hydraulics, Recent Trends in River Corridor Management, Lecture Notes in Civil Engineering 229, pp. 165-176, 2022.

    59-22   Philippe April LeQuéré, Scouring around multiple structures in extreme flow conditions, Thesis, University of Ottawa, Ottawa, ON, Canada, 2022.

    51-22   Xianzheng Zhang, Chenxiao Tang, Yajie Yu, Chuan Tang, Ning Li, Jiang Xiong, Ming Chen, Some considerations for using numerical methods to simulate possible debris flows: The case of the 2013 and 2020 Wayao debris flows (Sichuan, China), Water, 14.7; 1050, 2022. doi.org/10.3390/w14071050

    50-22   Daniel Valero, Daniel B. Bung, Sebastien Erpicum, Yann Peltier, Benjamin Dewals, Unsteady shallow meandering flows in rectangular reservoirs: A modal analysis of URANS modelling, Journal of Hydro-environment Research, 42; pp. 12-20, 2022. doi.org/10.1016/j.jher.2022.03.002

    49-22   Behzad Noroozi, Jalal Bazargan, Comparing the behavior of ogee and piano key weirs under unsteady flows, Journal of Irrigation and Water Engineering, 12.3; pp. 97-120. doi.org/10.22125/iwe.2022.146390

    47-22   Chen Xiaoting, Huang Bolin, Li Bin, Jiang Xiannian, Risk assessment study on landslide-generated impulse waves: case study from Zhongliang Reservoir in Chongqing, China, Bulletin of Engineering Geology and the Environment, 81; 158, 2022. doi.org/10.1007/s10064-022-02629-8

    45-22   Mehmet Cihan Aydin, Havva Seda Aytemur, Ali Emre Ulu, Experimental and numerical investigation on hydraulic performance of slit-check dams in subcritical flow condition, Water Resources Management, 36; pp. 1693-1710, 2022. doi.org/10.1007/s11269-022-03103-6

    43-22   Suresh Modalavalasa, Vinay Chembolu, Subashisa Dutta, Vinayak Kulkarni, Combined effect of bridge piers and floodplain vegetation on main channel hydraulics, Experimental Thermal and Fluid Science, 136; 110669, 2022. doi.org/10.1016/j.expthermflusci.2022.110669

    40-22   Mohammad Bagherzadeh, Farhad Mousavi, Mohammad Manafpour, Reza Mirzaee, Khosrow Hoseini, Numerical simulation and application of soft computing in estimating vertical drop energy dissipation with horizontal serrated edge, Water Supply, 127, 2022. doi.org/10.2166/ws.2022.127

    39-22   Masumeh Rostam Abadi, Saeed Kazemi Mohsenabadi, Numerical study of the weir angle on the flow pattern and scour around the submerged weirs, International Journal of Modern Physics C, 2022. doi.org/10.1142/S0129183122501108

    38-22   Vahid Hassanzadeh Vayghan, Mirali Mohammadi, Behzad Shakouri, Experimental and numerical examination of flow resistance in plane bed streams, Arabian Journal of Geosciences, 15; 483, 2022. doi.org/10.1007/s12517-022-09691-2

    36-22   Kyong Oh Baek, Byong Jo Min, Investigation for flow characteristics of ice-harbor type fishway installed at mid-sized streams in Korea, Journal of Korea Water Resources Association, 55.1; pp. 33-42, 2022. 

    34-22   Kyong Oh Baek, Jeong-Min Lee, Eun-Jin Han, Young-Do Kim, Evaluating attraction and passage efficiencies of pool-weir type fishways based on hydraulic analysis, Applied Sciences, 12.4; 1880, 2022. doi.org/10.3390/app12041880

    33-22   Christopher Paschmann, David F. Vetsch, Robert M. Boes, Design of desanding facilities for hydropower schemes based on trapping efficiency, Water, 14.4; 520, 2022. doi.org/10.3390/w14040520

    29-22   Mehdi Heyrani, Abdolmajid Mohammadian, Ioan Nistor, Omerul Faruk Dursun, Application of numerical and experimental modeling to improve the efficiency of Parshall flumes: A review of the state-of-the-art, Hydrology, 9.2; 26 2022. doi.org/10.3390/hydrology9020026

    28-22   Kiyoumars Roushangar, Samira Akhgar, Saman Shanazi, The effect of triangular prismatic elements on the hydraulic performance of stepped spillways in the skimming flow regime: An experimental study and numerical modeling, Journal of Hydroinformatics, 2022. doi.org/10.2166/hydro.2022.031

    26-22   Jorge Augusto Toapaxi Alvarez, Roberto Silva, Cristina Torres, Modelación numérica tridimensional del medidor de caudal Palmer-Bowlus aplicando el programa FLOW-3D (Three-dimensional numerical modeling of the Palmer-Bowlus measuring flume applying the FLOW-3D program), Revista Politécnica, 49.1; 2022. doi.org/10.33333/rp.vol49n1.04 

    25-22   Shubing Dai, Sheng Jin, Numerical investigations of unsteady critical flow conditions over an obstacle using three models, Physics of Fluids, 34.2; 2022. doi.org/10.1063/5.0077585

    23-22   Negar Ghahramani, H. Joanna Chen, Daley Clohan, Shielan Liu, Marcelo Llano-Serna, Nahyan M. Rana, Scott McDougall, Stephen G. Evans, W. Andy Take, A benchmarking study of four numerical runout models for the simulation of tailings flows, Science of the Total Environment, 827; 154245, 2022. doi.org/10.1016/j.scitotenv.2022.154245

    22-22   Bahador Fatehi-Nobarian, Razieh Panahi, Vahid Nourani, Investigation of the Effect of Velocity on Secondary Currents in Semicircular Channels on Hydraulic Jump Parameters, Iranian Journal of Science and Technology: Transactions of Civil Engineering, 2022. doi.org/10.1007/s40996-021-00800-x

    21-22   G. Viccione, C. Izzo, Three-dimensional CFD modelling of urban flood forces on buildings: A case study, Journal of Physics: Conference Series, 2162; 012020, 2022. doi.org/10.1088/1742-6596/2162/1/012020

    20-22   Tohid Jamali Rovesht, Mohammad Manafpour, Mehdi Lotfi, Effects of flow condition and chute geometry on the shockwaves formed on chute spillway, Journal of Water Supply: Research and Technology-Aqua, 71.2; pp. 312-329, 2022. doi.org/10.2166/aqua.2022.139

    17-22   Yansong Zhang, Jianping Chen, Fujun Zhou, Yiding Bao, Jianhua Yan, Yiwei Zhang, Yongchao Li, Feifan Gu, Qing Wang, Combined numerical investigation of the Gangda paleolandslide runout and associated dam breach flood propagation in the upper Jinsha River, SE Tibetan Plateau, Landslides, 2022. doi.org/10.1007/s10346-021-01768-5

    16-22   I.A. Hernández-Rodríguez, J. López-Ortega, G. González-Blanco, R. Beristain-Cardoso, Performance of the UASB reactor during wastewater treatment and the effect of the biogas bubbles on its hydrodynamics, Environmental Technology, pp. 1-21, 2022. doi.org/10.1080/09593330.2022.2028015

    15-22   Xu Deng, Sizhong He, Zhouhong Cao, Numerical investigation of the local scour around a coconut tree root foundation under wave-current joint actions, Ocean Engineering, 245; 110563, 2022. doi.org/10.1016/j.oceaneng.2022.110563

    14-22   Rasool Kosaj, Rafid S. Alboresha, Sadeq O. Sulaiman, Comparison between numerical Flow3d software and laboratory data, for sediment incipient motion, IOP Conference Series: Earth and Environmental Science, 961; 012031, 2022. doi.org/10.1088/1755-1315/961/1/012031

    13-22   Joseph M. Sinclair, S. Karan Venayagamoorthy, Timothy K. Gates, Some insights on flow over sharp-crested weirs using computational fluid dynamics: Implications for enhanced flow measurement, Journal of Irrigation and Drainage Engineering, 148.6; 2022. doi.org/10.1061/(ASCE)IR.1943-4774.0001652

    12-22   Mete Koken, Ismail Aydin, Serhan Ademoglu, An iterative hydraulic design methodology based on numerical modeling for piano key weirs, Journal of Hydro-environment Research, 40; pp. 131-141, 2022. doi.org/10.1016/j.jher.2022.01.002

    11-22   Najam us Saqib, Muhammad Akbar, Huali Pan, Guoqiang Ou, Muhammad Mohsin, Assad Ali, Azka Amin, Numerical analysis of pressure profiles and energy dissipation across stepped spillways having curved risers, Applied Sciences, 12.1; 448, 2022. doi.org/10.3390/app12010448

    9-22   Amir Bordbar, Soroosh Sharifi, Hassan Hemida, Investigation of scour around two side-by-side piles with different spacing ratios in live-bed, Lecture Notes in Civil Engineering, 208; pp. 302-309, 2022. doi.org/10.1007/978-981-16-7735-9_33

    8-22    Jian-cheng Li, Wei Wang, Yan-ming Zheng, Xiao-hao Wen, Jing Feng, Li Sheng, Chen Wang, Ming-kun Qiu, Using computational fluid dynamic simulation with Flow-3D to reveal the origin of the mushroom stone in the Xiqiao Mountain of Guangdong, China, Journal of Mountain Science, 19; pp. 1-15, 2022. doi.org/10.1007/s11629-021-7019-5

    4-22   Ankur Kapoor, Aniruddha D. Ghare, Avinash M. Badar, CFD simulations of conical central baffle flumes, Journal of Irrigation and Drainage Engineering, 148.2, 2022. doi.org/10.1061/(ASCE)IR.1943-4774.0001653

    2-22   Ramtin Sabeti, Mohammad Heidarzadeh, Numerical simulations of tsunami wave generation by submarine landslides: Validation and sensitivity analysis to landslide parameters, Journal of Waterway, Port, Coastal, and Ocean Engineering, 148.2; 05021016, 2022. doi.org/10.1061/(ASCE)WW.1943-5460.0000694

    1-22   Juan Francisco Fuentes-Pérez, Ana L. Quaresma, Antonio Pinheiro, Francisco Javier Sanz-Ronda, OpenFOAM vs FLOW-3D: A comparative study of vertical slot fishway modelling, Ecological Engineering, 174, 2022.

    145-21   Ebrahim Hamid Hussein Al-Qadami, Zahiraniza Mustaffa, Eduardo Martínez-Gomariz, Khamaruzaman Wan Yusof, Abdurrasheed S. Abdurrasheed, Syed Muzzamil Hussain Shah, Numerical simulation to assess floating instability of small passenger vehicle under sub-critical flow, Lecture Notes in Civil Engineering, 132; pp. 258-265, 2021. doi.org/10.1007/978-981-33-6311-3_30

    140-21   J. Zulfan, B.M.Ginting, Investigation of spillway rating curve via theoretical formula, laboratory experiment, and 3D numerical modeling: A case study of the Riam Kiwa Dam, Indonesia, IOP Conference Series: Earth and Environmental Science, 930; 012030, 2021. doi.org/10.1088/1755-1315/930/1/012030

    130-21   A.S.N. Amirah, F.Y. Boon, K.A. Nihla, Z.M. Salwa, A.W. Mahyun, N. Yaacof, Numerical simulation of flow within a storage area of HDPE modular pavement, IOP Conference Series: Earth and Environmental Science, 920; 012044, 2021. doi.org/10.1088/1755-1315/920/1/012044

    129-21   Z.M. Yusof, Z.A.L. Shirling, A.K.A. Wahab, Z. Ismail, S. Amerudin, A hydrodynamic model of an embankment breaching due to overtopping flow using FLOW-3D, IOP Conference Series: Earth and Environmental Science, 920; 012036, 2021. doi.org/10.1088/1755-1315/920/1/012036

    125-21   Ketaki H. Kulkarni, Ganesh A. Hinge, Comparative study of experimental and CFD analysis for predicting discharge coefficient of compound broad crested weir, Water Supply, 2021. doi.org/10.2166/ws.2021.403

    119-21   Yan Liang, Yiqun Hou, Wangbin Hu, David Johnson, Junxing Wang, Flow velocity preference of Schizothorax oconnori Lloyd swimming upstream, Global Ecology and Conservation, 32; e01902, 2021. doi.org/10.1016/j.gecco.2021.e01902

    116-21   Atabak Feizi, Aysan Ezati, Shadi Alizadeh Marallo, Investigation of hydrodynamic characteristics of flow caused by dam break around a downstream obstacle considering different reservoir shapes, Numerical Methods in Civil Engineering, 6.2; pp. 36-48, 2021.

    114-21   Jackson Tellez-Alvarez, Manuel Gómez, Beniamino Russo, Marko Amezaga-Kutija, Numerical and experimental approaches toestimate discharge coefficients and energy loss coefficients in pressurized grated inlets, Hydrology, 8.4; 162, 2021. doi.org/10.3390/hydrology8040162

    113-21   Alireza Khoshkonesh, Blaise Nsom, Fariba Ahmadi Dehrashid, Payam Heidarian, Khuram Riaz, Comparison of the SWE and 3D models in simulation of the dam-break flow over the mobile bed, 5th Scientific Conference of Applied Research in Science and Technology of Iran, 2021.

    103-21   Farshid Mosaddeghi, Numerical modeling of dam breach in concrete gravity dams, Thesis, Middle East Technical University, Ankara, Turkey, 2021.

    102-21   Xu Deng, Sizhong He, Zhouhong Cao, Tao Wu, Numerical investigation of the hydrodynamic response of an impermeable sea-wall subjected to artificial submarine landslide-induced tsunamis, Landslides, 2021. doi.org/10.1007/s10346-021-01773-8

    100-21   Jinmeng Yang, Zhenzhong Shen, Jing Zhang, Xiaomin Teng, Wenbing Zhang, Jie Dai, Experimental and numerical investigation of flow over a spillway bend with different combinations of permeable spur dikes, Water Supply, ws2021335, 2021. doi.org/10.2166/ws.2021.335

    99-21   Nigel A. Temple, Josh Adams, Evan Blythe, Zidane Twersky, Steve Blair, Rick Harter, Investigating the performance of novel oyster reef materials in Apalachicola Bay, Florida, ASBPA National Coastal Conference, New Orleans, LA, USA, September 28-October 1, 2021.

    94-21   Xiaoyang Shen, Mario Oertel, Comparitive study of nonsymmetrical trapezoidal and rectangular piano key weirs with varying key width ratios, Journal of Hydraulic Engineering, 147.11, 2021. doi.org/10.1061/(ASCE)HY.1943-7900.0001942

    93-21   Aysar Tuama Al-Awadi, Mahmoud Saleh Al-Khafaji, CFD-based model for estimating the river bed morphological characteristics near cylindrical bridge piers due to debris accumulation, Water Resources, 48; pp. 763-773, 2021. doi.org/10.1134/S0097807821050031

    92-21   Juan Francisco Macián-Pérez, Francisco José Vallés-Morán, Rafael García-Bartual, Assessment of the performance of a modified USBR Type II stilling basin by a validated CFD model, Journal of Irrigation and Drainage Engineering , 147.11, 2021. doi.org/10.1061/(ASCE)IR.1943-4774.0001623

    91-21   Ali Yıldız, Ali İhsan Martı, Mustafa Göğüş, Numerical and experimental modelling of flow at Tyrolean weirs, Flow Measurement and Instrumentation, 81; 102040, 2021. doi.org/10.1016/j.flowmeasinst.2021.102040

    90-21   Yasamin Aghaei, Fouad Kilanehei, Shervin Faghihirad, Mohammad Nazari-Sharabian, Dynamic pressure at flip buckets of chute spillways: A numerical study, International Journal of Civil Engineering, 2021. doi.org/10.1007/s40999-021-00670-4

    88-21   Shang-tuo Qian, Yan Zhang, Hui Xu, Xiao-sheng Wang, Jian-gang Feng, Zhi-xiang Li, Effects of surface roughness on overflow discharge of embankment weirs, Journal of Hydrodynamics, 33; pp. 773-781, 2021. doi.org/10.1007/s42241-021-0068-y

    86-21   Alkistis Stergiopoulou, Vassilios Stergiopoulos, CFD simulations of tubular Archimedean screw turbines harnessing the small hydropotential of Greek watercourses, International Journal of Energy and Environment, 12.1; pp. 19-30, 2021.

    85-21   Jun-tao Ren, Xue-fei Wu, Ting Zhang, A 3-D numerical simulation of the characteristics of open channel flows with submerged rigid vegetation, Journal of Hydrodynamics, 33; pp. 833-843, 2021. doi.org/10.1007/s42241-021-0063-3

    84-21   Rasoul Daneshfaraz, Amir Ghaderi, Maryam Sattariyan, Babak Alinejad, Mahdi Majedi Asl, Silvia Di Francesco, Investigation of local scouring around hydrodynamic and circular pile groups under the influence of river material harvesting pits, Water, 13.6; 2192, 2021. doi.org/10.3390/w13162192

    83-21   Mahdi Feizbahr, Navid Tonekaboni, Guang-Jun Jiang, Hong-Xia Chen, Optimized vegetation density to dissipate energy of flood flow in open canals, Mathematical Problems in Engineering, 2021; 9048808, 2021. doi.org/10.1155/2021/9048808

    80-21   Wenjun Liu, Bo Wang, Yakun Guo, Numerical study of the dam-break waves and Favre waves down sloped wet rigid-bed at laboratory scale, Journal of Hydrology, 602; 126752, 2021. doi.org/10.1016/j.jhydrol.2021.126752

    79-21   Zhen-Dong Shen, Yang Zhang, The three-dimensional simulation of granular mixtures weir, IOP Conference Series: Earth and Environmental Science, 820; 012024, 2021. doi.org/10.1088/1755-1315/820/1/012024

    75-21   Mehrdad Ghorbani Mooselu, Mohammad Reza Nikoo, Parnian Hashempour Bakhtiari, Nooshin Bakhtiari Rayani, Azizallah Izady, Conflict resolution in the multi-stakeholder stepped spillway design under uncertainty by machine learning techniques, Applied Soft Computing, 110; 107721, 2021. doi.org/10.1016/j.asoc.2021.107721

    73-21   Romain Van Mol, Plunge pool rehabilitation with prismatic concrete elements – Case study and physical model of Ilarion dam in Greece, Infoscience (EPFL Scientific Publications), 2021.

    70-21   Khosro Morovati, Christopher Homer, Fuqiang Tian, Hongchang Hu, Opening configuration design effects on pooled stepped chutes, Journal of Hydraulic Engineering, 147.9, 2021. doi.org/10.1061%2F(ASCE)HY.1943-7900.0001897

    68-21   R. Daneshfaraz, E. Aminvash, S. Di Francesco, A. Najibi, J. Abraham, Three-dimensional study of the effect of block roughness geometry on inclined drop, Numerical Methods in Civil Engineering, 6.1; pp. 1-9, 2021. 

    66-21   Benjamin Hohermuth, Lukas Schmoker, Robert M. Boes, David Vetsch, Numerical simulation of air entrainment in uniform chute flow, Journal of Hydraulic Research, 59.3; pp. 378-391, 2021. doi.org/10.1080/00221686.2020.1780492

    65-21   Junjun Tan, Honglin Tan, Elsa Goerig, Senfan Ke, Haizhen Huang, Zhixiong Liu, Xiaotao Shi, Optimization of fishway attraction flow based on endemic fish swimming performance and hydraulics, Ecological Engineering, 170; 106332, 2021. doi.org/10.1016/j.ecoleng.2021.106332

    63-21   Erdinc Ikinciogullari, Muhammet Emin Emiroglu, Mehmet Cihan Aydin, Comparison of scour properties of classical and trapezoidal labyrinth weirs, Arabian Journal for Science and Engineering, 2021. doi.org/10.1007/s13369-021-05832-z

    59-21   Elias Wehrmeister, José J. Ota, Separation in overflow spillways: A computational analysis, Journal of Hydraulic Research, 59, 2021. doi.org/10.1080/00221686.2021.1908438

    53-21   Zongxian Liang, John Ditter, Riadh Atta, Brian Fox, Karthik Ramaswamy, Numerical modeling of tailings dam break using a Herschel-Bulkley rheological model, USSD Annual Conference, online, May 11-21, 2021. 

    51-21   Yansong Zhang, Jianping Chen, Chun Tan, Yiding Bao, Xudong Han, Jianhua Yan, Qaiser Mehmood, A novel approach to simulating debris flow runout via a three-dimensional CFD code: A case study of Xiaojia Gully, Bulletin of Engineering Geology and the Environment, 80.5, 2021. doi.org/10.1007/s10064-021-02270-x

    49-21   Ramtin Sabeti, Mohammad Heidarzadeh, Preliminary results of numerical simulation of submarine landslide-generated waves, EGU General Assembly 2021, online, April 19-30, 2021. doi.org/10.5194/egusphere-egu21-284

    48-21   Anh Tuan Le, Ken Hiramatsu, Tatsuro Nishiyama, Hydraulic comparison between piano key weir and rectangular labyrinth weir, International Journal of GEOMATE, 20.82; pp. 153-160, 2021. doi.org/10.21660/2021.82.j2106

    46-21   Maoyi Luo, Faxing Zhang, Zhaoming Song, Liyuan Zhang, Characteristics of flow movement in complex canal system and its influence on sudden pollution accidents, Mathematical Problems in Engineering, 6617385, 2021. doi.org/10.1155/2021/6617385

    42-21   Jakub Major, Martin Orfánus, Zbyněk Zachoval, Flow over broad-crested weir with inflow by approach shaft – Numerical model, Civil Engineering Journal, 30.1; 19, 2021. doi.org/10.14311/CEJ.2021.01.0019 

    41-21   Amir Ghaderi, Saeed Abbasi, Experimental and numerical study of the effects of geometric appendance elements on energy dissipation over stepped spillway, Water, 13.7; 957, 2021. doi.org/10.3390/w13070957

    38-21   Ana L. Quaresma, António N. Pinheiro, Modelling of pool-type fishways flows: Efficiency and scale effects assessment, Water, 13.6; 851, 2021. doi.org/10.3390/w13060851

    37-21   Alireza Khoshkonesh, Blaise Nsom, Farhad Bahmanpouri, Fariba Ahmadi Dehrashid, Atefah Adeli, Numerical study of the dynamics and structure of a partial dam-break flow using the VOF Method, Water Resources Management, 35; pp. 1513-1528, 2021. doi.org/10.1007/s11269-021-02799-2

    36-21   Amir Ghaderi, Mehdi Dasineh, Francesco Aristodemo, Constanza Aricò, Numerical simulations of the flow field of a submerged hydraulic jump over triangular macroroughnesses, Water, 13.5; 674, 2021. doi.org/10.3390/w13050674

    35-21   Hongliang Qi, Junxing Zheng, Chenguang Zhang, Modeling excess shear stress around tandem piers of the longitudinal bridge by computational fluid dynamics, Journal of Applied Water Engineering and Research, 2021. doi.org/10.1080/23249676.2021.1884614

    31-21   Seth Siefken, Robert Ettema, Ari Posner, Drew Baird, Optimal configuration of rock vanes and bendway weirs for river bends: Numerical-model insights, Journal of Hydraulic Engineering, 147.5, 2021. doi.org/10.1061/(ASCE)HY.1943-7900.0001871

    29-21   Débora Magalhães Chácara, Waldyr Lopes Oliveira Filho, Rheology of mine tailings deposits for dam break analyses, REM – International Engineering Journal, 74.2; pp. 235-243, 2021. doi.org/10.1590/0370-44672020740098

    27-21   Ling Peng, Ting Zhang, Youtong Rong, Chunqi Hu, Ping Feng, Numerical investigation of the impact of a dam-break induced flood on a structure, Ocean Engineering, 223; 108669, 2021. doi.org/10.1016/j.oceaneng.2021.108669

    26-21   Qi-dong Hou, Hai-bo Li, Yu-Xiang Hu, Shun-chao Qi, Jian-wen Zhou, Overtopping process and structural safety analyses of the earth-rock fill dam with a concrete core wall by using numerical simulations, Arabian Journal of Geosciences, 14; 234, 2021. doi.org/10.1007/s12517-021-06639-w

    25-21   Filipe Romão, Ana L. Quaresma, José M. Santos, Susana D. Amaral, Paulo Branco, António N. Pinheiro, Performance and fish transit time over vertical slots, Water, 13.3; 275, 2021. doi.org/10.3390/w13030275

    23-21   Jiahou Hu, Chengwei Na, Yi Wang, Study on discharge velocity of tailings mortar in dam break based on FLOW-3D, IOP Conference Series: Earth and Environmental Science, 6th International Conference on Hydraulic and Civil Engineering, Xi’an, China, December 11-13, 2020, 643; 012052, 2021. doi.org/10.1088/1755-1315/643/1/012052

    21-21   Asad H. Aldefae, Rusul A. Alkhafaji, Experimental and numerical modeling to investigate the riverbank’s stability, SN Applied Sciences, 3; 164, 2021. doi.org/10.1007/s42452-021-04168-5

    20-21   Yangliang Lu, Jinbu Yin, Zhou Yang, Kebang Wei, Zhiming Liu, Numerical study of fluctuating pressure on stilling basin slabwith sudden lateral enlargement and bottom drop, Water, 13.2; 238, 2021. doi.org/10.3390/w13020238

    18-21   Prashant Prakash Huddar, Vishwanath Govind Bhave, Hydraulic structure design with 3D CFD model, Proceedings, 25th International Conference on Hydraulics, Water Resources and Coastal Engineering (HYDRO 2020), Odisha, India, March 26-28, 2021.

    17-21   Morteza Sadat Helbar, Atefah Parvaresh Rizi, Javad Farhoudi, Amir Mohammadi, 3D flow simulation to improve the design and operation of the dam bottom outlets, Arabian Journal of Geosciences, 14; 90, 2021. doi.org/10.1007/s12517-020-06378-4

    15-21   Charles R. Ortloff, Roman hydraulic engineering: The Pont du Gard Aqueduct and Nemausus (Nîmes) Castellum, Water, 13.1; 54, 2021. doi.org/10.3390/w13010054

    12-21   Mehdi Karami Moghadam, Ata Amini, Ehsan Karami Moghadam, Numerical study of energy dissipation and block barriers in stepped spillways, Journal of Hydroinformatics, 23.2; pp. 284-297, 2021. doi.org/10.2166/hydro.2020.245

    08-21   Prajakta P. Gadge, M. R. Bhajantri, V. V. Bhosekar, Numerical simulations of air entraining characteristics over high head chute spillway aerator, Proceedings, ICOLD Symposium on Sustainable Development of Dams and River Basins, New Dehli, India, February 24 – 27, 2021.

    07-21   Pankaj Lawande, Computational fluid dynamics simulation methodologies for stilling basins, Proceedings, ICOLD Symposium on Sustainable Development of Dams and River Basins, New Dehli, India, February 24 – 27, 2021.

    Below is a collection of technical papers in our Water & Environmental Bibliography. All of these papers feature FLOW-3D results. Learn more about how FLOW-3D can be used to successfully simulate applications for the Water & Environmental Industry.

    02-21   Aytaç Güven, Ahmed Hussein Mahmood, Numerical investigation of flow characteristics over stepped spillways, Water Supply, in press, 2021. doi.org/10.2166/ws.2020.283

    01-21   Le Thi Thu Hien, Nguyen Van Chien, Investigate impact force of dam-break flow against structures by both 2D and 3D numerical simulations, Water, 13.3; 344, 2021. doi.org/10.3390/w13030344

    125-20   Farhad Bahmanpouri, Mohammad Daliri, Alireza Khoshkonesh, Masoud Montazeri Namin, Mariano Buccino, Bed compaction effect on dam break flow over erodible bed; experimental and numerical modeling, Journal of Hydrology, in press, 2020. doi.org/10.1016/j.jhydrol.2020.125645

    209-23   Cong Trieu Tran, Cong Ty Trinh, Prediction of the vortex evolution and influence analysis of rough bed in a hydraulic jump with the Omega-Liutex method, Tehnički Vjesnik, 30.6; 2023. doi.org/10.17559/TV-20230206000327

    203-23   Muhammad Waqas Zaffar, Ishtiaq Hassan, Zulfiqar Ali, Kaleem Sarwar, Muhammad Hassan, Muhammad Taimoor Mustafa, Faizan Ahmed Waris, Numerical investigation of hydraulic jumps with USBR and wedge-shaped baffle block basins for lower tailwater, AQUA – Water Infrastructure, Ecosystems and Society, 72.11; 2081, 2023. doi.org/10.2166/aqua.2023.261

    201-23   E.F.R. Bollaert, Digital cloud-based platform to predict rock scour at high-head dams, Role of Dams and Reservoirs in a Successful Energy Transition, Eds. Robert Boes, Patrice Droz, Raphael Leroy, 2023. doi.org/10.1201/9781003440420

    200-23   Iacopo Vona, Oysters’ integration on submerged breakwaters as nature-based solution for coastal protection within estuarine environments, Thesis, University of Maryland, 2023.

    198-23   Hao Chen, Xianbin Teng, Zhibin Zhang, Faxin Zhu, Jie Wang, Zhaohao Zhang, Numerical analysis of the influence of the impinging distance on the scouring efficiency of submerged jets, Fluid Dynamics & Materials Processing, 20.2; pp. 429-445, 2023. doi.org/10.32604/fdmp.2023.030585

    193-23   Chen Peng, Liuweikai Gu, Qiming Zhong, Numerical simulation of dam failure process based on FLOW-3D, Advances in Frontier Research on Engineering Structures, pp. 545-550, 2023. doi.org/10.3233/ATDE230245

    189-23   Rebecca G. Englert, Age J. Vellinga, Matthieu J.B. Cartigny, Michael A. Clare, Joris T. Eggenhuisen, Stephen M. Hubbard, Controls on upstream-migrating bed forms in sandy submarine channels, Geology, 51.12; PP. 1137-1142, 2023. doi.org/10.1130/G51385.1

    187-23   J.W. Kim, S.B. Woo, A numerical approach to the treatment of submerged water exchange processes through the sluice gates of a tidal power plant, Renewable Energy, 219.1; 119408, 2023. doi.org/10.1016/j.renene.2023.119408

    186-23   Chan Jin Jeong, Hyung Jun Park, Hyung Suk Kim, Seung Oh Lee, Study on fish-friendly flow characteristic in stepped fishway, Proceedings of the Korean Water Resources Association Conference, 2023. (In Korean)

    185-23   Jaehwan Yoo, Sedong Jang, Byunghyun Kim, Analysis of coastal city flooding in 2D and 3D considering extreme conditions and climate change, Proceedings of the Korean Water Resources Association Conference, 2023. (In Korean)

    180-23   Prathyush Nallamothu, Jonathan Gregory, Jordan Leh, Daniel P. Zielinski, Jesse L. Eickholt, Semi-automated inquiry of fish launch angle and speed for hazard analysis, Fishes, 8.10; 476, 2023. doi.org/10.3390/fishes8100476

    179-23   Reza Norouzi, Parisa Ebadzadeh, Veli Sume, Rasoul Daneshfaraz, Upstream vortices of a sluice gate: an experimental and numerical study, AQUA – Water Infrastructure, Ecosystems and Society, 72.10; 1906, 2023. doi.org/10.2166/aqua.2023.269

    178-23   Bai Hao Li, How Tion Puay, Muhammad Azfar Bin Hamidi, Influence of spur dike’s angle on sand bar formation in a rectangular channel, IOP Conference Series: Earth and Environmental Science, 1238; 012027, 2023. doi.org/10.1088/1755-1315/1238/1/012027

    177-23   Hao Zhe Khor, How Tion Puay, Influence of gate lip angle on downpull forces for vertical lift gates, IOP Conference Series: Earth and Environmental Science, 1238; 012019, 2023. doi.org/10.1088/1755-1315/1238/1/012019

    175-23   Juan Francisco Macián-Pérez, Rafael García-Bartual, P. Amparo López-Jiménez, Francisco José Vallés-Morán, Numerical modeling of hydraulic jumps at negative steps to improve energy dissipation in stilling basins, Applied Water Science, 13.203; 2023. doi.org/10.1007/s13201-023-01985-4

    174-23   Ahintha Kandamby, Dusty Myers, Narrows bypass chute CFD analysis, Dam Safety, 2023.

    173-23   H. Jalili, R.C. Mahon, M.F. Martinez, J.W. Nicklow, Sediment sluicing from the reservoirs with high efficiency, SEDHYD, 2023.

    170-23   Ramith Fernando, Gangfu Zhang, Beyond 2D: Unravelling bridge hydraulics with CFD modelling, 24th Queensland Water Symposium, 2023.

    169-23   K. Licht, G. Lončar, H. Posavčić, I. Halkijević, Short-time numerical simulation of ultrasonically assisted electrochemical removal of strontium from water, 18th International Conference on Environmental Science and Technology (CEST), 2023.

    166-23   Ebrahim Hamid Hussein Al-Qadami, Mohd Adib Mohammad Razi, Wawan Septiawan Damanik, Zahiraniza Mustaffa, Eduardo Martinez-Gomariz, Fang Yenn Teo, Anwar Ameen Hezam Saeed, Understanding the stability of passenger vehicles exposed to water flows through 3D CFD modelling, Sustainability, 15.17; 13262, 2023. doi.org/10.3390/su151713262

    165-23   Ebrahim Hamid Hussein Al-Qadami, Mohd Adib Mohammad Razi, Wawan Septiawan Damanik, Zahiraniza Mustaffa, Eduardo Martinez-Gomariz, Fang Yenn Teo, Anwar Ameen Hezam Saeed, 3-dimensional numerical study on the critical orientation of the flooded passenger vehicles, Engineering Letters, 31.3; 2023.

    124-20   John Petrie, Yan Qi, Mark Cornwell, Md Al Adib Sarker, Pranesh Biswas, Sen Du, Xianming Shi, Design of living barriers to reduce the impacts of snowdrifts on Illinois freeways, Illinois Center for Transportation Series No. 20-019, Research Report No. FHWA-ICT-20-012, 2020. doi.org/10.36501/0197-9191/20-019

    123-20   Mohammad Reza Namaee, Jueyi Sui, Yongsheng Wu, Natalie Linklater, Three-dimensional numerical simulation of local scour in the vicinity of circular side-by-side bridge piers with ice cover, Canadian Journal of Civil Engineering, 2020. doi.org/10.1139/cjce-2019-0360

    119-20   Tuğçe Yıldırım, Experimental and numerical investigation of vortex formation at multiple horizontal intakes, Thesis, Middle East Technical University, Ankara, Turkey, , 2020.

    118-20   Amir Ghaderi, Mehdi Dasineh, Francesco Aristodemo, Ali Ghahramanzadeh, Characteristics of free and submerged hydraulic jumps over different macroroughnesses, Journal of Hydroinformatics, 22.6; pp. 1554-1572, 2020. doi.org/10.2166/hydro.2020.298

    117-20   Rasoul Daneshfaraz, Amir Ghaderi, Aliakbar Akhtari, Silvia Di Francesco, On the effect of block roughness in ogee spillways with flip buckets, Fluids, 5.4; 182, 2020. doi.org/10.3390/fluids5040182

    115-20   Chi Yao, Ligong Wu, Jianhua Yang, Influences of tailings particle size on overtopping tailings dam failures, Mine Water and the Environment, 2020. doi.org/10.1007/s10230-020-00725-3

    114-20  Rizgar Ahmed Karim, Jowhar Rasheed Mohammed, A comparison study between CFD analysis and PIV technique for velocity distribution over the Standard Ogee crested spillways, Heliyon, 6.10; e05165, 2020. doi.org/10.1016/j.heliyon.2020.e05165

    113-20   Théo St. Pierre Ostrander, Analyzing hydraulics of broad crested lateral weirs, Thesis, University of Innsbruck, Innsbruck, Austria, 2020.

    111-20   Mahla Tajari, Amir Ahmad Dehghani, Mehdi Meftah Halaghi, Hazi Azamathulla, Use of bottom slots and submerged vanes for controlling sediment upstream of duckbill weirs, Water Supply, 20.8; pp. 3393-3403, 2020. doi.org/10.2166/ws.2020.238

    110-20   Jian Zhou, Subhas K. Venayagamoorthy, How does three-dimensional canopy geometry affect the front propagation of a gravity current?, Physics of Fluids, 32.9; 096605, 2020. doi.org/10.1063/5.0019760

    106-20   Juan Francisco Macián-Pérez, Arnau Bayón, Rafael García-Bartual, P. Amparo López-Jiménez, Characterization of structural properties in high reynolds hydraulic jump based on CFD and physical modeling approaches, Journal of Hydraulic Engineering, 146.12, 2020. doi.org/10.1061/(ASCE)HY.1943-7900.0001820

    105-20   Bin Deng, He Tao, Changbo Jian, Ke Qu, Numerical investigation on hydrodynamic characteristics of landslide-induced impulse waves in narrow river-valley reservoirs, IEEE Access, 8; pp. 165285-165297, 2020. doi.org/10.1109/ACCESS.2020.3022651

    102-20   Mojtaba Mehraein, Mohammadamin Torabi, Yousef Sangsefidi, Bruce MacVicar, Numerical simulation of free flow through side orifice in a circular open-channel using response surface method, Flow Measurement and Instrumentation, 76; 101825, 2020. doi.org/10.1016/j.flowmeasinst.2020.101825

    101-20   Juan Francisco Macián Pérez, Numerical and physical modelling approaches to the study of the hydraulic jump and its application in large-dam stilling basins, Thesis, Universitat Politècnica de València, Valencia, Spain, 2020.

    99-20   Chen-Shan Kung, Pin-Tzu Su, Chin-Pin Ko, Pei-Yu Lee, Application of multiple intake heads in engineering field, Proceedings, 30th International Ocean and Polar Engineering Conference (ISOPE), Online, October 11-17,  ISOPE-I-20-3116, 2020.

    Below is a collection of technical papers in our Water & Environmental Bibliography. All of these papers feature FLOW-3D results. Learn more about how FLOW-3D can be used to successfully simulate applications for the Water & Environmental Industry.

    91-20      Selahattin Kocaman, Stefania Evangelista, Giacomo Viccione, Hasan Güzel, Experimental and numerical analysis of 3D dam-break waves in an enclosed domain with a single oriented obstacle, Environmental Science Proceedings, 2; 35, 2020. doi.org/10.3390/environsciproc2020002035

    89-20      Andrea Franco, Jasper Moernaut, Barbara Schneider-Muntau, Michael Strasser, Bernhard Gems, The 1958 Lituya Bay tsunami – pre-event bathymetry reconstruction and 3D numerical modelling utilising the computational fluid dynamics software Flow-3D, Natural Hazards and Earth Systems Sciences, 20; pp. 2255–2279, 2020. doi.org/10.5194/nhess-20-2255-2020

    88-20      Cesar Simon, Eddy J. Langendoen, Jorge D. Abad, Alejandro Mendoza, On the governing equations for horizontal and vertical coupling of one- and two-dimensional open channel flow models, Journal of Hydraulic Research, 58.5; pp. 709-724, 2020. doi.org/10.1080/00221686.2019.1671507

    87-20       Mohammad Nazari-Sharabian, Moses Karakouzian, Donald Hayes, Flow topology in the confluence of an open channel with lateral drainage pipe, Hydrology, 7.3; 57, 2020. doi.org/10.3390/hydrology7030057

    84-20       Naohiro Takeichi, Takeshi Katagiri, Harumi Yoneda, Shusaku Inoue, Yusuke Shintani, Virtual Reality approaches for evacuation simulation of various disasters, Collective Dynamics (originally presented in Proceedings from the 9th International Conference on Pedestrian and Evacuation Dynamics (PED2018), Lund, Sweden, August 21-23, 2018), 5, 2020. doi.org/10.17815/CD.2020.93

    83-20       Eric Lemont, Jonathan Hill, Ryan Edison, A problematic installation: CFD modelling of waste stabilisation pond mixing alternatives, Ozwater’20, Australian Water Association, Online, June 2, 2020, 2020.

    77-20       Peng Yu, Ruigeng Hu, Jinmu Yang, Hongjun Liu, Numerical investigation of local scour around USAF with different hydraulic conditions under currents and waves, Ocean Engineering, 213; 107696, 2020. doi.org/10.1016/j.oceaneng.2020.107696

    76-20       Alireza Mojtahedi, Nasim Soori, Majid Mohammadian, Energy dissipation evaluation for stepped spillway using a fuzzy inference system, SN Applied Sciences, 2; 1466, 2020. doi.org/10.1007/s42452-020-03258-0

    74-20       Jackson D., Tellez Alvarez E., Manuel Gómez, Beniamino Russo, Modelling of surcharge flow through grated inlet, Advances in Hydroinformatics: SimHydro 2019 – Models for Extreme Situations and Crisis Management, Nice, France, June 12-14, 2019, pp. 839-847, 2020. doi.org/10.1007/978-981-15-5436-0_65

    73-20       Saurav Dulal, Bhola NS Ghimire, Santosh Bhattarai, Ram Krishna Regmi, Numerical simulation of flow through settling basin: A case study of Budhi-Ganga Hydropower Project (BHP), International Journal of Engineering Research & Technology (IJERT), 9.7; pp. 992-998, 2020.

    70-20       B. Nandi, S. Das, A. Mazumdar, Experimental analysis and numerical simulation of hydraulic jump, IOP Conference Series: Earth and Environmental Science, 2020 6th International Conference on Environment and Renewable Energy, Hanoi, Vietnam, February 24-26, 505; 012024, 2020. doi.org/10.1088/1755-1315/505/1/012024

    69-20       Amir Ghaderi, Rasoul Daneshfaraz, Mehdi Dasineh, Silvia Di Francesco, Energy dissipation and hydraulics of flow over trapezoidal–triangular labyrinth weirs, Water (Special Issue: Combined Numerical and Experimental Methodology for Fluid–Structure Interactions in Free Surface Flows), 12.7; 1992, 2020. doi.org/10.3390/w12071992

    68-20       Jia Ni, Linwei Wang, Xixian Chen, Luan Luan Xue, Isam Shahrour, Effect of the fish-bone dam angle on the flow mechanisms of a fish-bone type dividing dyke, Marine Technology Society Journal, 54.3; pp. 58-67, 2020. doi.org/10.4031/MTSJ.54.3.9

    67-20       Yu Zhuang, Yueping Yin, Aiguo Xing, Kaiping Jin, Combined numerical investigation of the Yigong rock slide-debris avalanche and subsequent dam-break flood propagation in Tibet, China, Landslides, 17; pp. 2217-2229, 2020. doi.org/10.1007/s10346-020-01449-9

    66-20       A. Ghaderi, R. Daneshfaraz, S. Abbasi, J. Abraham, Numerical analysis of the hydraulic characteristics of modified labyrinth weirs, International Journal of Energy and Water Resources, 4.2, 2020. doi.org/10.1007/s42108-020-00082-5

    65-20      D.P. Zielinski, S. Miehls, G. Burns, C. Coutant, Adult sea lamprey espond to induced turbulence in a low current system, Journal of Ecohydraulics, 5, 2020. doi.org/10.1080/24705357.2020.1775504

    63-20       Raffaella Pellegrino, Miguel Ángel Toledo, Víctor Aragoncillo, Discharge flow rate for the initiation of jet flow in sky-jump spillways, Water, Special Issue: Planning and Management of Hydraulic Infrastructure, 12.6; 1814, 2020. doi.org/10.3390/w12061814

    59-20       Nesreen Taha, Maged M. El-Feky, Atef A. El-Saiad, Ismail Fathy, Numerical investigation of scour characteristics downstream of blocked culverts, Alexandria Engineering Journal, 59.5; pp. 3503-3513, 2020. doi.org/10.1016/j.aej.2020.05.032

    57-20       Charles Ortloff, The Hydraulic State: Science and Society in the Ancient World, Routledge, London, UK, eBook ISBN: 9781003015192, 2020. doi.org/10.4324/9781003015192

    54-20       Navid Aghajani, Hojat Karami, Hamed Sarkardeh, Sayed‐Farhad Mousavi, Experimental and numerical investigation on effect of trash rack on flow properties at power intakes, Journal of Applied Mathematics and Mechanics (ZAMM), online pre-issue, 2020. doi.org/10.1002/zamm.202000017

    53-20     Tian Zhou, Theodore Endreny, The straightening of a river meander leads to extensive losses in flow complexity and ecosystem services, Water (Special Issue: A Systems Approach of River and River Basin Restoration), 12.6; 1680, 2020. doi.org/10.3390/w12061680

    50-20       C.C. Battiston, F.A. Bombardelli, E.B.C. Schettini, M.G. Marques, Mean flow and turbulence statistics through a sluice gate in a navigation lock system: A numerical study, European Journal of Mechanics – B/Fluids, 84; pp.155-163, 2020. doi.org/10.1016/j.euromechflu.2020.06.003

    47-20       Mohammad Nazari-Sharabian, Aliasghar Nazari-Sharabian, Moses Karakouzian, Mehrdad Karami, Sacrificial piles as scour countermeasures in river bridges: A numerical study using FLOW-3D, Civil Engineering Journal, 6.6; pp. 1091-1103, 2020. doi.org/10.28991/cej-2020-03091531

    44-20    Leena Jaydeep Shevade, L. James Lo, Franco A. Montalto, Numerical 3D model development and validation of curb-cut inlet for efficiency prediction, Water, 12; 1791, 2020. doi.org/10.3390/w12061791

    43-20       Vitor Hugo Pereira de Morais, Tiago Zenker Gireli, Paulo Vatavuk, Numerical and experimental models applied to an ogee crest spillway and roller bucket stilling basin, Brazilian Journal of Water Resources, 2020. doi.org/10.1590/2318-0331.252020190005

    42-20       Chen Xie, Qin Chen, Gang Fan, Chen Chen, Numerical simulation of the natural erosion and breaching process of the “10.11” Baige Landslide Dam on the Jinsha River, Dam Breach Modelling and Risk Disposal, pp. 376-377, International Conference on Embankment Dams (ICED), Beijing, China, June 5 – 7, 2020. doi.org/10.1007/978-3-030-46351-9_40

    41-20       Niloofar Aghili Mahabadi, Hamed Reza Zarif Sanayei, Performance evaluation of bilateral side slopes in piano key weirs by numerical simulation, Modeling Earth Systems and Environment, 6; pp. 1477-1486, 2020. doi.org/10.1007/s40808-020-00764-3

    40-20       P. April Le Quéré, I. Nistor, A. Mohammadian, Numerical modeling of tsunami-induced scouring around a square column: Performance assessment of FLOW-3D and Delft3D, Journal of Coastal Research (preprint), 2020. doi.org/10.2112/JCOASTRES-D-19-00181

    39-20       Jian Zhou, Subhas K. Venayagamoorthy, Impact of ambient stable stratification on gravity currents propagating over a submerged canopy, Journal of Fluid Mechanics, 898; A15, 2020. doi.org/10.1017/jfm.2020.418

    37-20     Aliasghar Azma, Yongxiang Zhang, The effect of variations of flow from tributary channel on the flow behavior in a T-shape confluence, Processes, 8; 614, 2020. doi.org/10.3390/pr8050614

    35-20     Selahattin Kocaman, Hasan Güzel, Stefania Evangelista, Hatice Ozmen-Cagatay, Giacomo Viccione, Experimental and numerical analysis of a dam-break flow through different contraction geometries of the channel, Water, 12; 1124, 2020. doi.org/10.3390/w12041124

    32-20       Adriano Henrique Tognato, Modelagem CFD da interação entre hidrodinâmica costeira e quebra-mar submerso: estudo de caso da Ponta da Praia em Santos, SP (CFD modeling of interaction between sea waves and submerged breakwater at Ponta de Praia – Santos, SP: a case study, Thesis, Universidad Estadual de Campinas, Campinas, Brazil, 2020.

    31-20   Hamidreza Samma, Amir Khosrojerdi, Masoumeh Rostam-Abadi, Mojtaba Mehraein and Yovanni Cataño-Lopera, Numerical simulation of scour and flow field over movable bed induced by a submerged wall jet, Journal of Hydroinformatics, 22.2, pp. 385-401, 2020. doi.org/10.2166/hydro.2020.091

    28-20   Halah Kais Jalal and Waqed H. Hassan, Three-dimensional numerical simulation of local scour around circular bridge pier using FLOW-3D software, IOP Conference Series: Materials Science and Engineering, art. no. 012150, 3rd International Conference on Engineering Sciences, Kerbala, Iraq, November 4-6, 2019745. doi.org/10.1088/1757-899X/745/1/012150

    25-20   Faizal Yusuf and Zoran Micovic, Prototype-scale investigation of spillway cavitation damage and numerical modeling of mitigation options, Journal of Hydraulic Engineering, 146.2, 2020. doi.org/10.1061/(ASCE)HY.1943-7900.0001671

    24-20   Huan Zhang, Zegao Yin, Yipei Miao, Minghui Xia and Yingnan Feng, Hydrodynamic performance investigation on an upper and lower water exchange device, Aquacultural Engineering, 90, art. no. 102072, 2020. doi.org/10.1016/j.aquaeng.2020.102072

    22-20   Yu-xiang Hu, Zhi-you Yu and Jian-wen Zhou, Numerical simulation of landslide-generated waves during the 11 October 2018 Baige landslide at the Jinsha River, Landslides, 2020. doi.org/10.1007/s10346-020-01382-x

    19-20   Amir Ghaderi, Mehdi Dasineh, Saeed Abbasi and John Abraham, Investigation of trapezoidal sharp-crested side weir discharge coefficients under subcritical flow regimes using CFD, Applied Water Science, 10, art. no. 31, 2020. doi.org/10.1007/s13201-019-1112-8

    18-20   Amir Ghaderi, Saeed Abbasi, John Abraham and Hazi Mohammad Azamathulla, Efficiency of trapezoidal labyrinth shaped stepped spillways, Flow Measurement and Instrumentation, 72, art. no. 101711, 2020. doi.org/10.1016/j.flowmeasinst.2020.101711

    16-20   Majid Omidi Arjenaki and Hamed Reza Zarif Sanayei, Numerical investigation of energy dissipation rate in stepped spillways with lateral slopes using experimental model development approach, Modeling Earth Systems and Environment, 2020. doi.org/10.1007/s40808-020-00714-z

    15-20   Bo Wang, Wenjun Liu, Wei Wang, Jianmin Zhang, Yunliang Chen, Yong Peng, Xin Liu and Sha Yang, Experimental and numerical investigations of similarity for dam-break flows on wet bed, Journal of Hydrology, 583, art. no. 124598, 2020. doi.org/10.1016/j.jhydrol.2020.124598

    14-20   Halah Kais Jalal and Waqed H. Hassan, Effect of bridge pier shape on depth of scour, IOP Conference Series: Materials Science and Engineering, art. no. 012001, 3rd International Conference on Engineering Sciences, Kerbala, Iraq, November 4-6, 2019671. doi.org/10.1088/1757-899X/671/1/012001

    13-20   Shahad R. Mohammed, Basim K. Nile and Waqed H. Hassan, Modelling stilling basins for sewage networks, IOP Conference Series: Materials Science and Engineering, art. no. 012111, 3rd International Conference on Engineering Sciences, Kerbala, Iraq, November 4-6, 2019671. doi.org/10.1088/1757-899X/671/1/012111

    11-20   Xin Li, Liping Jin, Bernie A. Engel, Zeng Wang, Wene Wang, Wuquan He and Yubao Wang, Influence of the structure of cylindrical mobile flumes on hydraulic performance characteristics in U-shaped channels, Flow Measurement and Instrumentation, 72, art. no. 101708, 2020. doi.org/10.1016/j.flowmeasinst.2020.101708

    10-20   Nima Aein, Mohsen Najarchi, Seyyed Mohammad Mirhosseini Hezaveh, Mohammad Mehdi Najafizadeh and Ehsanollah Zeigham, Simulation and prediction of discharge coefficient of combined weir–gate structure, Proceedings of the Institution of Civil Engineers – Water Management (ahead of print), 2020. doi.org/10.1680/jwama.19.00047

    03-20   Agostino Lauria, Francesco Calomino, Giancarlo Alfonsi, and Antonino D’Ippolito, Discharge coefficients for sluice gates set in weirs at different upstream wall inclinations, Water, 12, art. no. 245, 2020. doi.org/10.3390/w12010245

    113-19   Ruidong An, Jia Li, Typical biological behavior of migration and flow pattern creating for fish schooling, E-Proceedings, 38th IAHR World Congress, Panama City, Panama, September 1-6, 2019.

    112-19   Wenjun Liu, Bo Wang, Hang Wang, Jianmin Zhang, Yunliang Chen, Yong Peng, Xin Liu, Sha Yang, Experimental and numerical modeling of dam-break flows in wet downstream conditions, E-Proceedings, 38th IAHR World Congress, Panama City, Panama, September 1-6, 2019.

    111-19   Zhang Chendi, Liu Yingjun, Xu Mengzhen, Wang Zhaoyin, The 3D numerical study on flow properties of individual step-pool, Proceedings: 14th International Symposium on River Sedimentation, Chengdu, China, September 16-19, 2019.

    110-19   Mason Garfield, The effects of scour on the flow field at a bendway weir, Thesis: Colorado State University, Fort Collins, Colorado, Colorado State University, Fort Collins, Colorado.

    109-19   Seth Siefken, Computational fluid dynamics models of Rio Grande bends fitted with rock vanes or bendway weirs, Thesis: Colorado State University, Fort Collins, Colorado, Colorado State University, Fort Collins, Colorado.

    108-19   Benjamin Israel Devadason and Paul Schweiger, Decoding the drowning machines: Using CFD modeling to predict and design solutions to remediate the dangerous hydraulic roller at low head dams, The Journal of Dam Safety, 17.1, pp. 20-31, 2019.

    106-19   Amir Ghaderi and Saeed Abbasi, CFD simulations of local scouring around airfoil-shaped bridge piers with and without collar, Sādhanā, art. no. 216, 2019. doi.org/10.1007/s12046-019-1196-8

    105-19   Jacob van Alwon, Numerical and physical modelling of aerated skimming flows over stepped spillways, Thesis, University of Leeds, Leeds, United Kingdom, 2019.

    100-19   E.H. Hussein Al-Qadami, A.S. Abdurrasheed, Z. Mustaffa, K.W. Yusof, M.A. Malek and A. Ab Ghani, Numerical modelling of flow characteristics over sharp crested triangular hump, Results in Engineering, 4, art. no. 100052, 2019. doi.org/10.1016/j.rineng.2019.100052

    99-19   Agostino Lauria, Francesco Calomino, Giancarlo Alfonsi, and Antonino D’Ippolito, Discharge coefficients for sluice gates set in weirs at different upstream wall inclinations, Water, 12.1, art. no. 245, 2019. doi.org/10.3390/w12010245

    98-19   Redvan Ghasemlounia and M. Sedat Kabdasli, Surface suspended sediment distribution pattern for an unexpected flood event at Lake Koycegiz, Turkey, Proceedings, 14th National Conference on Watershed Management Sciences and Engineering, Urmia, Iran, July 16-17, 2019.

    97-19   Brian Fox, Best practices for simulating hydraulic structures with CFD, Proceedings, Dam Safety 2019, Orlando, Florida, USA, September 8-12, 2019.

    96-19   John Wendelbo, Verification of CFD predictions of self-aeration onset on stepped chute spillways, Proceedings, Dam Safety 2019, Orlando, Florida, USA, September 8-12, 2019.

    95-19   Pankaj Lawande, Anurag Chandorkar and Adhirath Mane, Predicting discharge rating curves for tainter gate controlled spillway using CFD simulations, Proceedings, 24th HYDRO 2019, International Conference, Hyderabad, India, December 18-20, 2019.

    91-19   Gyeong-Bo Kim, Wei Cheng, Richards C. Sunny, Juan J. Horrillo, Brian C. McFall, Fahad Mohammed, Hermann M. Fritz, James Beget, and Zygmunt Kowalik , Three Dimensional Landslide Generated Tsunamis: Numerical and Physical Model Comparisons, Landslides, 2019. doi.org/10.1007/s10346-019-01308-2

    85-19   Susana D. Amaral, Ana L. Quaresma, Paulo Branco, Filipe Romão, Christos Katopodis, Maria T. Ferreira, António N. Pinheiro, and José M. Santos, Assessment of retrofitted ramped weirs to improve passage of potamodromous fish, Water, 11, art. no. 2441, 2019. doi.org/10.3390/w11122441

    82-19   Shubing Dai, Yong He, Jijian Yang, Yulei ma, Sheng Jin, and Chao Liang, Numerical study of cascading dam-break characteristics using SWEs and RANS, Water Supply, 2019. doi.org/10.2166/ws.2019.168

    81-19   Kyong Oh Baek, Evaluation technique for efficiency of fishway based on hydraulic analysis, Journal of Korea Water Resources Association, 52.spc2, pp. 855-863, 2019. doi.org/10.3741/JKWRA.2019.52.S-2.855

    80-19   Yongye Li, Yuan Gao, Xiaomeng Jia, Xihuan Sun, and Xuelan Zhang, Numerical simulations of hydraulic characteristics of a flow discharge measurement process with a plate flowmeter in a U-channel, Water, art. no. 2392, 2019. doi.org/10.3390/w11112382

    76-19   Youtong Rong, Ting Zhang, Yanchen Zheng, Chunqi Hu, Ling Peng, and Ping Feng, Three-dimensional urban flood inundation simulation based on digital aerial photogrammetry, Journal of Hydrology, in press, 2019. doi.org/10.1016/j.jhydrol.2019.124308

    74-19   Youtong Rong, Ting Zhang, Ling Peng, and Ping Feng, Three-dimensional numerical simulation of dam discharge and flood routing in Wudu Reservoir, Water, 11, art. no. 2157, 2019. doi.org/10.3390/w11102157

    70-19   Le Thi Thu Hien, Study the flow over chute spillway by both numerical and physical models, Proceedings, pp. 845-851, 10th International Conference on Asian and Pacific Coasts (APAC 2019), Hanoi, Vietnam, September 25-28, 2019. doi.org/10.1007/978-981-15-0291-0_116

    69-19   T. Vinh Cuong, N. Thanh Hung, V. Thanh Te, P. Anh Tuan, Analysis of spur dikes spatial layout to river bed degradation under reversing tidal flow, Proceedings, pp. 737-744, 10th International Conference on Asian and Pacific Coasts (APAC 2019), Hanoi, Vietnam, September 25-28, 2019. doi.org/10.1007/978-981-15-0291-0_101

    67-19   Zongshi Dong, Junxing Wang, David Florian Vetsch, Robert Michael Boes, and Guangming Tan, Numerical simulation of air–water two-phase flow on stepped spillways behind X-shaped flaring gate piers under very high unit discharge, Water, 11, art. no. 1956, 2019. doi.org/10.3390/w11101956

    66-19   Tony L. Wahl, Effect of boundary layer conditions on uplift pressures at open offset spillway joints, Sustainable and Safe Dams Around the World: Proceedings, 2019. doi.org/10.1201/9780429319778-182

    65-19   John Petrie, Kun Zhang, and Mahmoud Shehata, Numerical simulation of snow deposition around living snow fences, Community Center for Environmentally Sustainable Transportation in Cold Climates (CESTiCC), Project Report, 2019.

    64-19   Andrea Franco, Jasper Moernaut, Barbara Schneider-Muntau, Markus Aufleger, Michael Strasser, and Bernhard Gems, Lituya Bay 1958 Tsunami – detailed pre-event bathymetry reconstruction and 3D-numerical modelling utilizing the CFD software FLOW-3D, Natural Hazards and Earth Systems Sciences, under review, 2019. doi.org/10.5194/nhess-2019-285

    63-19   J. Patarroyo, D. Damov, D. Shepherd, G. Snyder, M. Tremblay, and M. Villeneuve, Hydraulic design of stepped spillway using CFD supported by physical modelling: Muskrat Falls hydroelectric generating facility, Sustainable and Safe Dams Around the World: Proceedings, , pp. 205-219, 2019. doi.org/10.1201/9780429319778-19

    61-19   A.S. Abdurrasheed, K.W. Yusof, E.H. Hussein Alqadami, H. Takaijudin, A.A. Ghani, M.M. Muhammad, A.T. Sholagberu, M.K. Zainalfikry, M. Osman, and M.S. Patel, Modelling of flow parameters through subsurface drainage modules for application in BIOECODS, Water, 11, art. no. 1823, 2019. doi.org/10.3390/w11091823

    59-19     Brian Fox and Robert Feurich, CFD analysis of local scour at bridge piers, Proceedings of the Federal Interagency Sedimentation and Hydraulic Modeling Conference (SEDHYD), Reno, Nevada, June 24-28, 2019.

    56-19     Pankaj Lawande, Brian Fox, and Anurag Chandorkar, Three dimensional CFD modeling of flow over a tainter gate spillway, International Dam Safety Conference, Bhubaneswar, Odisha, India, February 13-14, 2019.

    49-19     Yousef Sangsefidi, Bruce MacVicar, Masoud Ghodsian, Mojtaba Mehraein, Mohammadamin Torabi, and Bruce M. Savage, Evaluation of flow characteristics in labyrinth weirs using response surface methodology, Flow Measurement and Instrumentation, Vol. 69, 2019. doi: 10.1016/j.flowmeasinst.2019.101617

    43-19     Gongyun Liao, Zancheng Tang, and Fei Zhu, Self-cleaning performance of double-layer porous asphalt pavements with different granular diameters and layer combinations, 19th COTA International Conference of Transportation, Nanjing, China, July 6-8, 2019.

    42-19     Tsung-Chun Ho, Gwo-Jang Hwang, Kao-Shu Hwang, Kuo-Cheng Hsieh, and Lung-Wei Chen, Experimental and numerical study on desilting efficiency of the bypassing tunnel for Nan-Hua reservoir, 3rd International Workshop on Sediment Bypass Tunnels, Taipei, Taiwan, April 9-12, 2019.

    41-19     Chang-Ting Hsieh, Sheng-Yung Hsu, and Chin-Pin Ko, Planning of sluicing tunnel in front of the Wushe dam – retrofit the existing water diversion tunnel as an example, 3rd International Workshop on Sediment Bypass Tunnels, Taipei, Taiwan, April 9-12, 2019.

    40-19     Chi-Lin Yang, Pang-ku Yang, Fu-June Wang, and Kuo-Cheng Hsieh, Study on the transportation of high-concentration sediment flow and the operation of sediment de-silting in Deji Reservoir, 3rd International Workshop on Sediment Bypass Tunnels, Taipei, Taiwan, April 9-12, 2019.

    39-19   Sam Glovik and John Wendelbo, Advanced CFD air entrainment capabilities for baffle drop structure design, NYWEA 91st Annual Meeting, New York, NY, February 3-6, 2019.

    36-19     Ahmed M. Helmi, Heba T. Essawy, and Ahmed Wagdy, Three-dimensional numerical study of stacked drop manholes, Journal of Irrigation and Drainage Engineering, Vol. 145, No. 9, 2019. doi: 10.1061/(ASCE)IR.1943-4774.0001414

    33-19     M. Cihan Aydin, A. Emre Ulu, and Çimen Karaduman, Investigation of aeration performance of Ilısu Dam outlet using two-phase flow model, Applied Water Science, Vol. 9, No. 111, 2019. doi: 10.1007/s13201-019-0982-0

    16-19     Bernard Twaróg, The analysis of the reactive work of the Alden Turbine, Technical Transactions I, Environmental Engineering, 2019. doi: 10.4467/2353737XCT.19.010.10050

    14-19     Guodong Li, Xingnan Li, Jian Ning, and Yabing Deng, Numerical simulation and engineering application of a dovetail-shaped bucket, Water, Vol. 11, No. 2, 2019. doi: 10.3390/w11020242

    13-19     Ilaria Rendina, Giacomo Viccione, and Leonardo Cascini, Kinematics of flow mass movements on inclined surfaces, Theoretical and Computational Fluid Dynamics, Vol. 33, No. 2, pp. 107-123, 2019. doi: 10.1007/s00162-019-00486-y

    10-19     O.K. Saleh, E.A. Elnikhely, and Fathy Ismail, Minimizing the hydraulic side effects of weirs construction by using labyrinth weirs, Flow Measurement and Instrumentation, Vol. 66, pp. 1-11, 2019. doi: 10.1016/j.flowmeasinst.2019.01.016

    05-19   Hakan Ersoy, Murat Karahan, Kenan Gelişli, Aykut Akgün, Tuğçe Anılan, M. Oğuz Sünnetci, Bilgehan Kul Yahşi, Modelling of the landslide-induced impulse waves in the Artvin Dam reservoir by empirical approach and 3D numerical simulation, Engineering Geology, Vol. 249, pp. 112-128, 2019. doi: 10.1016/j.enggeo.2018.12.025

    96-18     Kyung-Seop Sin, Robert Ettema, Christopher I. Thornton, Numerical modeling to assess the influence of bendway weirs on flow distribution in river beds, Task 4 of Study: Native Channel Topography and Rock-Weir Structure Channel-Maintenance Techniques, U.S. Dept. of the Interior. CSU-HYD Report No. 2018-1, 2018.

    95-18   Thulfikar Razzak Al-Husseini, Hayder A. Al-Yousify and Munaf A. Al-Ramahee, Experimental and numerical study of the effect of the downstream spillway face’s angle on the stilling basin’s energy dissipation, International Journal of Civil Engineering and Technology, 9.8, pp. 1327-1337, 2018.

    94-18   J. Michalski and J. Wendelbo, Utilizing CFD methods as a forensic tool in pipeline systems to assess air/water transient issues, Proceedings, 7, pp. 5519-5527, 91st Water Environment Federation Technical Exhibition & Conference (WEFTEC), New Orleans, LA, United States, September 29 – October 3, 2018. doi.org/10.2175/193864718825138817

    79-18 Harold Alvarez and John Wendelbo, Estudio de 3 modelos matemáticos para similar olas producidas por derrumbes en embalses y esfuerzos en compuertas, XXVIII Congreso Latinoamericano de Hidráulica, Buenos Aires, Argentina, September 2018. (In Spanish)

    70-18   Michael Pfister, Gaetano Crispino, Thierry Fuchsmann, Jean-Marc Ribi and Corrado Gisonni, Multiple inflow branches at supercritical-type vortex drop shaft, Journal of Hydraulic Engineering, Vol. 144, No. 11, 2018. doi.org/10.1061/(ASCE)HY.1943-7900.0001530

    67-18   F. Nunes, J. Matos and I. Meireles, Numerical modelling of skimming flow over small converging spillways, 3rd International Conference on Protection against Overtopping, June 6-8, 2018, Grange-over-Sands, UK, 2018.

    66-18   Maria João Costa, Maria Teresa Ferreira, António N. Pinheiro and Isabel Boavida, The potential of lateral refuges for Iberian barbel under simulated hydropeaking conditions, Ecological Engineering, Vol. 124, 2018. doi.org/10.1016/j.ecoleng.2018.07.029

    63-18   Michael J. Seluga, Frederick Vincent, Samuel Glovick and Brad Murray, A new approach to hydraulics in baffle drop shafts to address dry and wet weather flow in combined sewer tunnels, North American Tunneling Conference Proceedings, June 24-27, 2018, Washington, D.C. pp. 448-461, 2018. © Society for Mining, Metallurgy & Exploration

    62-18   Ana Quaresma, Filipe Romão, Paulo Branco, Maria Teresa Ferreira and António N. Pinheiro, Multi slot versus single slot pool-type fishways: A modelling approach to compare hydrodynamics, Ecological Engineering, Vol. 122, pp. 197-206, 2018. doi.org/10.1016/j.ecoleng.2018.08.006

    57-18   Amir Isfahani, CFD modeling of piano key weirs using FLOW-3D, International Dam Safety Conference, January 23-24, 2018, Thiruvananthapuram, Kerala, India; Technical Session 1A, Uncertainties and Risk Management in Dams, 2018.

    49-18   Jessica M. Thompson, Jon M. Hathaway and John S. Schwartz, Three-dimensional modeling of the hydraulic function and channel stability of regenerative stormwater conveyances, Journal of Sustainable Water in the Built Environment, vol. 4, no.3, 2018. doi.org/10.1061/JSWBAY.0000861

    46-18   A.B. Veksler and S.Z. Safin, Hydraulic regimes and downstream scour at the Kama Hydropower Plant, Power Technology and Engineering, vol. 51, no. 5, pp. 2-13, 2018. doi.org/10.1007/s10749-018-0862-z

    45-18   H. Omara and A. Tawfik, Numerical study of local scour around bridge piers, 9th Annual Conference on Environmental Science and Development, Paris, France, Feb. 7-9, 2018; IOP Conference Series: Earth and Environmental Sciences, vol. 151, 2018. doi.org:10.1088/1755-1315/151/1/012013

    40-18   Vincent Libaud, Christophe Daux and Yanis Oukid, Practical Capacities and Challenges of 3D CFD Modelling: Feedback Experience in Engineering Projects, Advances in Hydroinformatics, pp. 767-780, 2018. doi.org/10.1007/978-981-10-7218-5_55

    39-18   Khosro Morovati and Afshin Eghbalzadeh, Study of inception point, void fraction and pressure over pooled stepped spillways using FLOW-3D, International Journal of Numerical Methods for Heat & Fluid Flow, vol. 28, no. 4, pp.982-998, 2018. doi.org/10.1108/HFF-03-2017-0112

    34-18   Tomasz Siuta, The impact of deepening the stilling basin on the characteristics of hydraulic jump, Technical Transactions, vol. 3, pp. 173-186, 2018.

    32-18   Azin Movahedi, M.R. Kavianpour, M. R and Omid Aminoroayaie Yamini, Evaluation and modeling scouring and sedimentation around downstream of large dams, Environmental Earth Sciences, vol. 77, no. 8, pp. 320, 2018. doi.org/10.1007/s12665-018-7487-2

    31-18   Yang Song, Ling-Lei Zhang, Jia Li, Min Chen and Yao-Wen Zhang, Mechanism of the influence of hydrodynamics on Microcystis aeruginosa, a dominant bloom species in reservoirs, Science of The Total Environment, vol. 636, pp. 230-239, 2018. doi.org/10.1016/j.scitotenv.2018.04.257

    30-18   Shaolin Yang, Wanli Yang, Shunquan Qin, Qiao Li and Bing Yang, Numerical study on characteristics of dam-break wave, Ocean Engineering, vol. 159, pp.358-371, 2018. doi.org/10.1016/j.oceaneng.2018.04.011

    27-18   Rachel E. Chisolm and Daene C. McKinney, Dynamics of avalanche-generated impulse waves: three-dimensional hydrodynamic simulations and sensitivity analysis, Natural Hazards and Earth System Sciences, vol. 18, pp. 1373-1393, 2018. doi.org/10.5194/nhess-18-1373-2018.

    24-18   Han Hu, Zhongdong Qian, Wei Yang, Dongmei Hou and Lan Du, Numerical study of characteristics and discharge capacity of piano key weirs, Flow Measurement and Instrumentation, vol. 62, pp. 27-32, 2018. doi.org/10.1016/j.flowmeasinst.2018.05.004

    23-18   Manoochehr Fathi-Moghaddam, Mohammad Tavakol Sadrabadi and Mostafa Rahmanshahi, Numerical simulation of the hydraulic performance of triangular and trapezoidal gabion weirs in free flow condition, Flow Measurement and Instrumentation, vol. 62, pp. 93-104, 2018. doi.org/10.1016/j.flowmeasinst.2018.05.005

    22-18   Anastasios I.Stamou, Georgios Mitsopoulos, Peter Rutschmann and Minh Duc Bui, Verification of a 3D CFD model for vertical slot fish-passes, Environmental Fluid Mechanics, June 2018. doi.org/10.1007/s10652-018-9602-z

    17-18   Nikou Jalayeri, John Wendelbo, Joe Groeneveld, Andrew John Bearlin, and John Gulliver, Boundary dam total dissolved gas analysis using a CFD model, Proceedings from the U.S. Society on Dams Annual Conference, April 30 – May 4, 2018, © 2018 U.S. Society on Dams.

    12-18   Bernard Twaróg, Interaction between hydraulic conditions and structures – fluid structure interaction problem solving. A case study of a hydraulic structure, Technical Transactions 2/2018, Environmental Engineering, DOI: 10.4467/2353737XCT.18.029.8002

    06-18   Oscar Herrera-Granados, Turbulence Flow Modeling of One-Sharp-Groyne Field, © Springer International Publishing AG 2018, M. B. Kalinowska et al. (eds.), Free Surface Flows and Transport Processes, GeoPlanet: Earth and Planetary Sciences, https://doi.org/10.1007/978-3-319-70914-7_12

    05-18  Shangtuo Qian, Jianhua Wu, Yu Zhou and Fei Ma, Discussion of “Hydraulic Performance of an Embankment Weir with Rough Crest” by Stefan Felder and Nushan Islam, J. Hydraul. Eng., 2018, 144(4): 07018003, © ASCE.

    04-18   Faezeh Tajabadi, Ehsan Jabbari and Hamed Sarkardeh, Effect of the end sill angle on the hydrodynamic parameters of a stilling basin, DOI 10.1140/epjp/i2018-11837-y, Eur. Phys. J. Plus (2018) 133: 10

    03-18   Dhemi Harlan, Dantje K. Natakusumah, Mohammad Bagus Adityawan, Hernawan Mahfudz and Fitra Adinata, 3D Numerical Modeling of Flow in Sedimentation Basin, MATEC Web of Conferences 147, 03012 (2018), https://doi.org/10.1051/matecconf/201814703012 SIBE 2017

    02-18   ARKAN IBRAHIM, AZHEEN KARIM and Mustafa GÜNAL, Simulation of local scour development downstream of broad-crested weir with inclined apron, European Journal of Science and Technology Special Issue, pp. 57-61, January 2018, Copyright © 2017 EJOSAT.

    62-17   Abbas Mansoori, Shadi Erfanian and Farhad Khamchin Moghadam, A study of the conditions of energy dissipation in stepped spillways with A-shaped step using FLOW-3D, Civil Engineering Journal, 3.10, 2017.

    57-17   Ben Modra, Brett Miller, Nigel Moon and Andrew Berghuis, Physical model testing of a bespoke articulated concrete block (ACB) fishway, 13th Hydraulics in Water Engineering Conference, Sydney, Nov. 13-18, 2017; Engineers Australia, pp. 301-309, 2017.

    53-17   C. Gonzalez, U. Baeumer and C. Russell, Natural disaster relief and recovery arrangements Fitzroy project, bridge scour remediation, 13th Hydraulics in Water Engineering Conference, Sydney. Nov. 13-18, 2017; Engineers Australia, pp. 274-281, 2017.

    52-17   Nigel Moon, Russell Merz, Sarah Luu and Daley Clohan, Utilising CFD modelling to conceptualise a novel rock ramp fishway design, 13th Hydraulics in Water Engineering Conference, Sydney, Nov. 13-18, 2017; Engineers Australia, pp. 382-389, 2017.

    50-17   B.M. Crookston, R.M. Anderson and B.P. Tullis, Free-flow discharge estimation method for Piano Key weir geometries, Journal of Hydro-environment Research (2017), http://dx.doi.org/10.1016/j.jher.2017.10.003.

    48-17   Jian Zhou, Physics of Environmental Flows Interacting with Obstacles, PhD Thesis: Colorado State University, Copyright by Jian Zhou 2017, All Rights Reserved.

    46-17   Michael Sturn, Bernhard Gems, Markus Aufleger, Bruno Mazzorana, Maria Papathoma-Köhle and Sven Fuchs, Scale Model Measurements of Impact Forces on Obstacles Induced by Bed-load Transport Processes, Proceedings of the 37th IAHR World Congress August 13 – 18, 2017, Kuala Lumpur, Malaysia.

    43-17   Paula Beceiro, Maria do Céu Almeida and Jorge Matos, Numerical modelling of air-water flows in sewer drops, Available Online 28 April 2017, wst2017246; DOI: 10.2166/wst.2017.246

    42-17   Arnau Bayon, Juan Pablo Toro,  Fabián A.Bombardelli, Jorge Matose and Petra Amparo López-Jiménez, Influence of VOF technique, turbulence model and discretization scheme on the numerical simulation of the non-aerated, skimming flow in stepped spillways, Journal of Hydro-environment Research, Available online 26 October 2017

    40-17   Sturm M, Gems B, Mazzorana B, Gabl R and Aufleger M, Validation of physical and 3D numerical modelling of hydrodynamic flow impacts on objects (Validierung experimenteller und 3-D-numerischer Untersuchungen zur Einwirkung hydrodynamischer Fließprozesse auf Objekte), Bozen-Bolzano Institutional Archive (BIA), ISSN: 0043-0978, https://bia.unibz.it/handle/10863/3893, 2017

    38-17   Tsung-Hsien Huang, Chyan-Deng Jan, and Yu-Chao Hsu, Numerical Simulations of Water Surface Profiles and Vortex Structure in a Vortex Settling Basin by using FLOW-3D, Journal of Marine Science and Technology, Vol. 25, No. 5, pp. 531-542 (2017) 531, DOI: 10.6119/JMST-017-0509-1

    36-17   Jacob van Alwon, Duncan Borman and Andrew Sleigh, Numerical Modelling of Aerated Flows Over Stepped Spillways, 37th IAHR World Congress, 2017.

    35-17   Abolfazl Nazari Giglou, John Alex Mccorquodale and Luca Solari, Numerical study on the effect of the spur dikes on sedimentation pattern, Ain Shams Engineering Journal, Available online 8 March 2017.

    33-17   Giovanni De Cesare, Khalid Essyad, Paloma Furlan, Vu Nam Khuong, Sean Mulligan, Experimental study at prototype scale of a self-priming free surface siphon, Congrès SHF : SIMHYDRO 2017, Nice, 14-16 June

    32-17   Kathryn Plymesser and Joel Cahoon, Pressure gradients in a steeppass fishway using a computational fluid dynamics model, Ecological Engineering 108 (2017) 277–283.

    31-17   M. Ghasemi, S. Soltani-Gerdefaramarzi, The Scour Bridge Simulation around a Cylindrical Pier Using FLOW-3D, Journal of Hydrosciences and Environment 1(2): 2017 46-54

    27-17   John Wendelbo and Brian Fox, CFD modeling of Piano Key weirs: validation and numerical parameter space analysis, 2017 Dam Safety, San Antonio, September 10-14, 2017, Copyright © 2017 Association of State Dam Safety Officials, Inc. All Rights Reserved.

    26-17   Brian Fox and John Wendelbo, Numerical modeling of Piano Key Weirs using FLOW-3D, USSD Annual Conference, Anaheim, CA, April 3- 7, 2017

    25-17   Rasoul Daneshfaraz, Sina Sadeghfam and Ali Ghahramanzadeh, Three-dimensional Numerical Investigation of Flow through Screens as Energy Dissipators, Canadian Journal of Civil Engineering, https://doi.org/10.1139/cjce-2017-0273

    23-17   J.M, Duguay, R.W.J. Lacey and J. Gaucher, A case study of a pool and weir fishway modeled with OpenFOAM and FLOW-3D, Ecological Engineering, Volume 103, Part A, June 2017, Pages 31-42

    22-17   Hanif Pourshahbaz, Saeed Abbasi and Poorya Taghvaei, Numerical scour modeling around parallel spur dikes in FLOW-3D, https://doi.org/10.5194/dwes-2017-21, Drinking Water Engineering and Science, © Author(s) 2017

    21-17   Hamid Mirzaei, Zohreh Heydari and Majid Fazli, The effect of meshing and comparing different models of turbulence in topographic prediction of bed and amplitude of flow around the groin in 90-degree arc with movable bed, Modeling Earth Systems and Environment, pp 1–16, July 2017

    13-17   Lan Qi, Hui Chen, Xiao Wang, Wencai Fei and Donghai Liu, Establishment and application of three-dimensional realistic river terrain in the numerical modeling of flow over spillways, Water Science & Technology: Water Supply | in press | 2017.

    11-17   Allison, M.A., Yuill, B.T., Meselhe, E.A., Marsh, J.K., Kolker, A.S., Ameen, A.D., Observational and numerical particle tracking to examine sediment dynamics in a Mississippi River delta diversion, Estuarine, Coastal and Shelf Science (2017), doi: 10.1016/j.ecss.2017.06.004.

    09-17   Hamid Mirzaei, Zohreh Heydari and Majid Fazli, The effect of meshing and comparing different turbulence models in predicting the topography of bed and flow field in the 90 degree bend with moving bed, M. Model. Earth Syst. Environ. (2017). doi:10.1007/s40808-017-0336-6

    03-17   Luis G. Castillo and José M. Carrillo, Comparison of methods to estimate the scour downstream of a ski jump, Civil Engineering Department, Universidad Politécnica de Cartagena, UPCT Paseo Alfonso XIII, 52 – 30203 Cartagena, Spain, International Journal of Multiphase Flow 92 (2017) 171–180.

    103-16 Daniel Valero and Rafael Garcia-Bartual, Calibration of an Air Entrainment Model for CFD Spillway Applications, Advances in Hydroinformatics, P. Gourbesville et al. (eds), pp. 571-582, 2016. doi.org/10.1007/978-981-287-615-7_38

    97-16   M. Taghavi and H. Ghodousi, A Comparison on Discharge Coefficients of Side and Normal Weirs with Suspended Flow Load using FLOW-3D, Indian Journal of Science and Technology, Vol 9(3), doi.org/10.17485/ijst/2016/v9i3/78537, January 2016.

    96-16   Luis G. Castillo and José M. Carrillo, Scour, Velocities and Pressures Evaluations Produced by Spillway and Outlets of DamWater 2016, 8(3), 68; doi.org/10.3390/w8030068.

    95-16   Majid Heydari and Alireza KhoshKonesh, The Comparison of the Performance of Prandtl Mixing Length, Turbulence Kinetic Energy, K-e, RNG and LES Turbulence Models in Simulation of the Positive Wave Motion Caused by Dam Break on the Erodible Bed, Indian Journal of Science and Technology, Vol 9(7), 2016. doi.org/10.17485/ijst/2016/v9i7/87856

    93-16   Saleh I. Khassaf, Ali N. Attiyah and Hayder A. Al-Yousify, Experimental investigation of compound side weir with modeling using computational fluid dynamic, International Journal of Energy and Environment, Volume 7, Issue 2, 2016 pp.169-178

    92-16   Jason Duguay and Jay Lacey, Modeling: OpenFOAM CFD Modeling Case Study of a Pool and Weir Fishway with Implications for Free-Surface Flows, International Conference on Engineering and Ecohydrology for Fish Passage 2016

    90-16   Giacomo Viccione, Vittorio Bovolin and Eugenio Pugliese Carratelli, A numerical investigation of liquid impact on planar surfaces, ECCOMAS Congress 2016 VII European Congress on Computational Methods in Applied Sciences and Engineering, Greece, June 2016.

    89-16   Giacomo Viccione, A numerical investigation of flow dynamics over a trapezoidal smooth open channel, ECCOMAS Congress 2016 VII European Congress on Computational Methods in Applied Sciences and Engineering, Greece, June 2016.

    87-16  Jian Zhou and Subhas K. Venayagamoorthy, Numerical simulations of intrusive gravity currents interacting with a bottom-mounted obstacle in a continuously stratified ambient, Environmental Fluid Mechanics, 17; 191–209, 2016. doi: 10.1007/s10652-016-9454-3

    86-16   Charles R. Ortloff, Similitude in Archaeology: Examining Agricultural System Science in PreColumbian Civilizations of Ancient Peru and Bolivia, Hydrol Current Res 7:259. doi: 10.4172/2157-7587.1000259, October 2016.

    85-16   Charles R. Ortloff, New Discoveries and Perspectives on Water Management at 300 Bc – Ad 1100 Tiwanaku’s Urban Center (Bolivia), MOJ Civil Eng 1(3): 00014. DOI: 10.15406/mojce.2016.01.00014.

    82-16   S. Paudel and N. Saenger, Grid refinement study for three dimensional CFD model involving incompressible free surface flow and rotating object, Computers & Fluids, Volume 143, http://dx.doi.org/10.1016/j.compfluid.2016.10.025, 17 January 2017, Pages 134–140

    77-16   José A. Vásquez, Daniel M. Robb, MODELACIÓN CFD DE ROTURA DE PRESAS EN PRESENCIA DE OBSTÁCULOS, XXVII CONGRESO LATINOAMERICANO DE HIDRÁULICA, LIMA, PERÚ, 28 AL 30 DE SETIEMBRE DE 2016.

    76-16   José A. Vásquez and Guilherme de Lima, MODELACIÓN CFD DE ONDAS TSUNAMI EN RESERVORIOS, LAGOS Y MINAS CAUSADAS POR DESLIZAMIENTOS DE LADERAS, XXVII CONGRESO LATINOAMERICANO DE HIDRÁULICA, LIMA, PERÚ, 28 AL 30 DE SETIEMBRE DE 2016.

    75-16   Bernhard Gems, Bruno Mazzorana, Thomas Hofer, Michael Sturm, Roman Gabl and Markus Aufleger, 3-D hydrodynamic modelling of flood impacts on a building and indoor flooding processes, Nat. Hazards Earth Syst. Sci., 16, 1351-1368, 2016, http://www.nat-hazards-earth-syst-sci.net/16/1351/2016/, doi:10.5194/nhess-16-1351-2016 © Author(s) 2016. This work is distributed under the Creative Commons Attribution 3.0 License.

    74-16   Roman Gabl, Jakob Seibl, Manfred Pfeifer, Bernhard Gems and Markus Aufleger, 3D-numerische Modellansätze für die Berechnung von Lawineneinstößen in Speicher (Concepts to simulate avalanche impacts into a reservoir based on 3D-numerics), Österr Wasser- und Abfallw (2016). doi:10.1007/s00506-016-0346-z.

    73-16   Sebastian Krzyzagorski, Roman Gabl, Jakob Seibl, Heidi Böttcher and Markus Aufleger, Implementierung eines schräg angeströmten Rechens in die 3D-numerische Berechnung mit FLOW-3D (Implementation of an angled trash rack in the 3D-numerical simulation with FLOW-3D), Österr Wasser- und Abfallw (2016) 68: 146. doi:10.1007/s00506-016-0299-2.

    71-16   Khosro Morovati, Afshin Eghbalzadeh and Saba Soori, Numerical Study of Energy Dissipation of Pooled Stepped Spillways, Civil Engineering Journal Vol. 2, No. 5, May, 2016.

    66-16   Sooyoung Kim, Seo-hye Choi and Seung Oh Lee, Analysis of Influence for Breach Flow According to Asymmetry of Breach Cross-section, Journal of the Korea Academia-Industrial cooperation Society, Vol. 17, No. 5 pp. 557-565, 2016, http://dx.doi.org/10.5762/KAIS.2016.17.5.557, ISSN 1975-4701 / eISSN 2288-4688.

    65-16   Dae-Geun Kim, Analysis of Overflow Characteristics around a Circular-Crested Weir by Using Numerical Model, Journal of Korean Society of Water and Wastewater Vol. 30, No. 2, April 2016.

    63-16   Farzad Ferdos and Bijan Dargahi, A study of turbulent flow in largescale porous media at high Reynolds numbers. Part II: flow physics, Journal of Hydraulic Research, 2016, DOI: 10.1080/00221686.2016.1211185.

    62-16   Farzad Ferdos and Bijan Dargahi, A study of turbulent flow in largescale porous media at high Reynolds numbers. Part I: numerical validation, Journal of Hydraulic Research, 2016, DOI: 10.1080/00221686.2016.1211184.

    60-16   Chia-Lin Chiu, Chia-Ming Fan and Shun-Chung Tsung, Numerical modeling for  periodic oscillation of free overfall in a vertical drop pool, DOI: 10.1061/(ASCE)HY.1943-7900.0001236. © 2016 American Society of Civil Engineers.

    54-16   Serife Yurdagul Kumcu, Investigation of Flow Over Spillway Modeling and Comparison between Experimental Data and CFD Analysis, KSCE Journal of Civil Engineering, (0000) 00(0):1-10, Copyright 2016 Korean Society of Civil Engineers, DOI 10.1007/s12205-016-1257-z.

    52-16   Gharehbaghi, A., Kaya, B. and Saadatnejadgharahassanlou, Two-Dimensional Bed Variation Models Under Non-equilibrium Conditions in Turbulent Streams, H. Arab J Sci Eng (2016). doi:10.1007/s13369-016-2258-4

    48-16   M. Mohsin Munir, Taimoor Ahmed, Javed Munir and Usman Rasheed, Application of Computational Flow Dynamics Analysis for Surge Inception and Propagation for Low Head Hydropower Projects, Proceedings of the Pakistan Academy of Sciences: Pakistan Academy of Sciences, A. Physical and Computational Sciences 53 (2): 177–185 (2016), Copyright © Pakistan Academy of Sciences

    46-16   Manuel Gómez, Joan Recasens, Beniamino Russo and Eduardo Martínez-Gomariz, Assessment of inlet efficiency through a 3D simulation: numerical and experimental comparison, wst2016326; DOI: 10.2166/wst.2016.326, August 2016

    45-16   Chia-Ying Chang, Frederick N.-F. Chou, Yang-Yih Chen, Yi-Chern Hsieh, Chia-Tzu Chang, Analytical and experimental investigation of hydrodynamic performance and chamber optimization of oscillating water column system, Energy 113 (2016) 597-614

    42-16   Bung, D. and Valero, D., Application of the Optical Flow Method to Velocity Determination, In B. Crookston & B. Tullis (Eds.), Hydraulic Structures and Water System Management, 6th IAHR International Symposium on Hydraulic Structures, Portland, OR, 27-30 June 2016, doi:10.15142/T3150628160853 (ISBN 978-1-884575-75-4).

    41-16   Valero, D., Bung, D., Crookston, B. and Matos, J., Numerical investigation of USBR type III stilling basin performance downstream of smooth and stepped spillways, In B. Crookston & B. Tullis (Eds.), Hydraulic Structures and Water System Management. 6th IAHR International Symposium on Hydraulic Structures, Portland, OR, 27-30 June 2016, doi:10.15142/T340628160853 (ISBN 978-1-884575-75-4).

    40-16   Bruce M. Savage, Brian M. Crookston and Greg S. Paxson, Physical and Numerical Modeling of Large Headwater Ratios for a 15° Labyrinth Spillway, J. Hydraul. Eng., 10.1061/(ASCE)HY.1943-7900.0001186, 04016046.

    36-16   Kai-Wen Hsiao, Yu-Chao Hsu, Chyan-Deng Jan, and Yu-Wen Su, Characteristics of Hydraulic Shock Waves in an Inclined Chute Contraction by Using Three Dimensional Numerical Model, Geophysical Research Abstracts, Vol. 18, EGU 2016-11505, 2016, EGU General Assembly 2016, © Author(s) 2016. CC Attribution 3.0 License.

    34-16   Dunlop, S., Willig, I., Paul, G., Cabinet Gorge Dam Spillway Modifications for TDG Abatement – Design Evolution and Field Performance, In B. Crookston & B. Tullis (Eds.), Hydraulic Structures and Water System Management. 6th IAHR International Symposium on Hydraulic Structures, Portland, OR, 27-30 June, 2016, doi:10.15142/T3650628160853 (ISBN 978-1-884575-75-4).

    33-16   Crispino, G., Dorthe, D., Fuchsmann, T., Gisonni, C., Pfister, M., Junction chamber at vortex drop shaft: case study of Cossonay, In B. Crookston & B. Tullis (Eds.), Hydraulic Structures and Water System Management, 6th IAHR International Symposium on Hydraulic Structures, Portland, OR, 27-30 June 2016, doi:10.15142/T350628160853 (ISBN 978-1-884575-75-4).

    32-16  Brown, K., Crookston, B., Investigating Supercritical Flows in Curved Open Channels with Three Dimensional Numerical Modeling, In B. Crookston & B. Tullis (Eds.), Hydraulic Structures and Water System Management, 6th IAHR International Symposium on Hydraulic Structures, Portland, OR, 27-30 June, 2016, doi:10.15142/T3580628160853 (ISBN 978-1-884575-75-4).

    31-16  Cicero, G, Influence of some geometrical parameters on Piano Key Weir discharge efficiency,In B. Crookston & B. Tullis (Eds.), Hydraulic Structures and Water System Management, 6th IAHR International Symposium on Hydraulic Structures, Portland, OR, 27-30 June, 2016, doi:10.15142/T3320628160853 (ISBN 978-1-884575-75-4).

    28-16   Anthoula Gkesouli, Maria Nitsa, Anastasios I. Stamou, Peter Rutschmann and Minh Duc Bui, Modeling the effect of wind in rectangular settling tanks for water supply, DOI: 10.1080/19443994.2016.1195290, Desalination and Water Treatment, June 22, 2016.

    27-16   Eugenio Pugliese Carratelli, Giacomo Viccione and Vittorio Bovolin, Free surface flow impact on a vertical wall: a numerical assessment, Theor. Comput. Fluid Dyn., DOI 10.1007/s00162-016-0386-9, February 2016.

    25-16   Daniel Valero and Daniel B. Bung, Sensitivity of turbulent Schmidt number and turbulence model to simulations of jets in crossflow, Environmental Modelling & Software 82 (2016) 218e228.

    24-16   Il Won Seo, Young Do Kim, Yong Sung Park and Chang Geun Song, Spillway discharges by modification of weir shapes and overflow surroundings, Environmental Earth Sciences, March 2016, 75:496, 14 March 2016

    23-16   Du Han Lee, Myounghwan Kim and Dong Sop Rhee, Evacuation Safety Evaluation of Inundated Stairs Using 3D Numerical Simulation, International Journal of Smart Home Vol. 10, No. 3, (2016), pp.149-158 http://dx.doi.org/10.14257/ijsh.2016.10.3.15

    22-16   Arnau Bayon, Daniel Valero, Rafael García-Bartual, Francisco Jose Valles-Moran and Amparo Lopez-Jimenez, Performance assessment of OpenFOAM and FLOW-3D in the numerical modeling of a low Reynolds number hydraulic jump, Environmental Modelling & Software 80 (2016) 322e335.

    21-16   Shima Bahadori and Mehdi Behdarvandi Askar, Investigating the Effect of Relative Width on Momentum Transfer between Main Channel and Floodplain in Rough Rectangular Compound Channel Sunder Varius Relative Depth Condition, Open Journal of Geology, 2016, 6, 225-231, Published Online April 2016 in SciRes.

    18-16   Ali Ahrari,  Hong Lei, Montassar Aidi Sharif, Kalyanmoy Deb and  Xiaobo Tan, Optimum Design of Artificial Lateral Line Systems for Object Tracking under Uncertain Conditions, COIN Report Number: 2016006

    16-16   Elena Battisacco, Giovanni De Cesare and Anton J. Schleiss, Re-establishment of a uniform discharge on the Olympic fountain in Lausanne, Journal of Applied Water Engineering and Research, (2016) DOI: 10.1080/23249676.2016.1163648.

    14-16   Shima Bahadori, Mehdi and Behdarvandi Askar, Investigating the Simultaneous Effect of Relative Width and Relative Roughness on Apparent Shear Stress in Symmetric Compound Rectangular Channels, JOURNAL OF CURRENT RESEARCH IN SCIENCE, ISSN 2322-5009 CODEN (USA): JCRSDJ, S (1), 2016: 654-660

    12-16   Charles R. Ortloff, Hydraulic Engineering Innovations at 100 BC- AD 300 Nabataean Petra (Jordan), In conference proceedings: De Aquaeductu atque Aqua Urbium Lyciae Pamphyliae Pisidiae. The Legacy of Sextus Julius Frontinus, Antalya, Turkey, G. Wiplinger, ed.  ISBN: 978-90-429-3361-3, 2016 Peeters Publisher, Leuven, Belgium.

    11-16 G. Robblee, S. Kees and B.M. Crookston, Schnabel Engineering; and K. Keel, Town of Hillsborough, Ensuring Water Supply Reliability with Innovative PK Weir Spillway Design, 36th USSD Annual Meeting and Conference, Denver, CO, April 11-15, 2016

    10-16 Tina Stanard and Victor Vasquez, Freese and Nichols, Inc.; Ruth Haberman, Upper Brushy Creek Water Control and Improvement District; Blake Tullis, Utah State University; and Bruce Savage, Idaho State University, Importance of Site Considerations for Labyrinth Spillway Hydraulic Design — Upper Brushy Creek Dam 7 Modernization, 36th USSD Annual Meeting and Conference, Denver, CO, April 11-15, 2016

    09-16 James R. Crowder, Brian M. Crookston, Bradley T. Boyer and J. Tyler Coats, Schnabel Engineering, Cultivating Ingenuity and Safety in Alabama: The Taming of Lake Ogletree Reservoir, 36th USSD Annual Meeting and Conference, Denver, CO, April 11-15, 2016

    08-16 Frank Lan, Robert Waddell and Michael Zusi, AECOM; and Brian Grant, Montana DNRC, Replacing Ruby Dam Outlet Uses Computational Fluid Dynamics to Model Energy Dissipation, 36th USSD Annual Meeting and Conference, Denver, CO, April 11-15, 2016

    07-16 Elise N. Dombeck, Federal Energy Regulatory Commission, Applications of FLOW-3D for Stability Analyses of Concrete Spillways at FERC Projects, 36th USSD Annual Meeting and Conference, Denver, CO, April 11-15, 2016

    06-16   Farhad Ghazizadeh and M. Azhdary Moghaddam, An Experimental and Numerical Comparison of Flow Hydraulic Parameters in Circular Crested Weir Using FLOW-3D, Civil Engineering Journal Vol. 2, No. 1, January, 2016

    05-16   Sadegh Dehdar-behbahani and Abbas Parsaie, Numerical modeling of flow pattern in dam spillway’s guide wall. Case study: Balaroud dam, Iran, doi:10.1016/j.aej.2016.01.006, February 2016.

    04-16   Oscar Herrera-Granados and Stanisław W. Kostecki, Numerical and physical modeling of water flow over the ogee weir of the new Niedów barrage, DOI: 10.1515/johh-2016-0013, J. Hydrol. Hydromech., 64, 2016, 1, 67–74

    03-16   B. Gems, B. Mazzorana, T. Hofer, M. Sturm, R. Gabl, M. Aufleger, 3D-hydrodynamic modelling of flood impacts on a building and indoor flooding processes, Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2015-326, 2016, Manuscript under review for journal Nat. Hazards Earth Syst. Sci., Published: 19 January 2016 © Author(s) 2016. CC-BY 3.0 License.

    124-15 Yousef Sangsefidi, Mojtaba Mehraein, and Masoud Ghodsian, Numerical simulation of flow over labyrinth spillways, Scientia Iranica, Transaction A, 22(5), 1779–1787, 2015.

    120-15   Du Han Lee, Myounghwan Kim and Dong Sop Rhee, Analysis of Critical Evacuation Condition on Inundated Stairs Using Numerical Simulation, Advanced Science and Technology Letters Vol.120 (GST 2015), pp.522-525 http://dx.doi.org/10.14257/astl.2015.120.104

    119-15  Shiqiang Ye and Paul Toth, Bank Erosion Control at Frederickhouse Dam, Ontario, CDA 2015 Annual Conference, Congrès annuel 2015 de l’ACB, Mississauga, ON, Canada, 2015 Oct 5-8

    118-15  D.M. Robb and J.A. Vasquez, Numerical simulation of dam-break flows using depth-averaged hydrodynamic and three-dimensional CFD models, 22nd Canadian Hydrotechnical Conference, Montreal, Quebec, April 29 – May 2, 2015

    117-15 Ashkan. Reisi, Parastoo. Salah, and Mohamad Reza. Kavianpour, Impact of Chute Walls Convergence Angle on Flow Characteristics of Spillways using Numerical Modeling, International Journal of Chemical, Environmental & Biological Sciences (IJCEBS), Volume 3, Issue 3 (2015) ISSN 2320–4087 (Online)

    115-15  Ivana Vouk, Field and Numerical Investigation of Mixing and Transport of Ammonia in the Ottawa River, Master’s Thesis: Department of Civil Engineering, University of Ottawa, August 2015, © Ivana Vouk, Canada 2016.

    113-15   J. Amblard, C. Pams Capoccioni, D. Nivon, L. Mellal, G. De Cesare, T. Ghilardi, M. Jafarnejad and E. Battisacco, Analysis of Ballast Transport in the Event of Overflowing of the Drainage System on High Speed Lines, International Journal of Railway Technology, Volume 4, 2015. doi:10.4203/ijr, t.4.xx.xx , ©Saxe-Coburg Publications, 2015

    111-15   Y. Oukid, V. Libaud and C. Daux, 3D CFD modelling of spillways -Practical feedback on capabilities and challenges, Hydropower & Dams Issue Six, 2015

    110-15  Zhiyong Zhang and Yuanping Yang, Numerical Study on Onset Condition of Scour Below Offshore Pipeline Under Reversing Tidal Flow, © EJGE, Vol. 20 [2015], Bund. 25

    109-15  He Baohua, Numerical Simulation Analysis of Karst Tunnel Water Bursting Movement, © EJGE, Vol. 20 [2015], Bund. 25

    105-15   Ali Yıldız and A. İhsan Martı, Comparison of Experimental Study and CFD Analysis of the Flow Under a Sluice Gate, Proceedings of International Conference on Structural Architectural and Civil Engineering Held on 21-22, Nov, 2015, in Dubai, ISBN:9788193137321

    104-15  Yehui Zhu and Liquan Xie, Numerical Analysis of Flow Effects on Water Interface over a Submarine Pipeline, Resources, Environment and Engineering II: Proceedings of the 2nd Technical Congress on Resources, Environment and Engineering (CREE 2015, Hong Kong, 25-26 September 2015), Edited by Liquan Xie, CRC Press 2015, Pages 99–104, DOI: 10.1201/b19136-16.

    100-15  Yizhou Xiao, Wene Wang, Xiaotao Hu, and Yan Zhou, Experimental and numerical research on portable short-throat flume in the field, Flow Measurement and Instrumentation, doi:10.1016/j.flowmeasinst.2015.11.003, Available online December 8, 2015

    99-15   Mehdi Taghavi and Hesam Ghodousi, Simulation of Flow Suspended Load in Weirs by Using FLOW-3D Model, Civil Engineering Journal Vol. 1, No. 1, November 2015

    98-15   Azin Movahedi, Ali Delavari and Massoud Farahi, Designing Manhole in Water Transmission Lines Using FLOW-3D Numerical Model, Civil Engineering Journal Vol. 1, No. 1, November 2015

    97-15   R. Gabl, J. Seibl, B. Gems, and M. Aufleger, 3-D numerical approach to simulate the overtopping volume caused by an impulse wave comparable to avalanche impact in a reservoir, Nat. Hazards Earth Syst. Sci., 15, 2617-2630, doi:10.5194/nhess-15-2617-2015, 2015.

    94-15   Jason Matthew Duguay and Jay Lacey, Numerical Study of an Innovative Fish Ladder Design for Perched Culverts, Canadian Journal of Civil Engineering, 10.1139/cjce-2014-0436, November 2015

    92-15   H. A. Hussein, R. Abdulla and  M. A. Md Said, Computational Investigation of Inlet Baffle Height on the Flow in a Rectangular Oil/Water Separator Tanks, Applied Mechanics and Materials, Vol. 802, pp. 587-592, Oct. 2015

    91-15   Mahmoud Mohammad Rezapour Tabari and Shiva Tavakoli, Effects of Stepped Spillway Geometry on Flow Pattern and Energy DissipationArabian Journal for Science and Engineering, October 2015

    87-15   Erin R. Ryan, Effects of Hydraulic Structures on Fish Passage – An Evaluation of 2D vs 3D Hydraulic Analysis Methods, Master’s Thesis: Civil and Environmental Engineering, Colorado State University, Summer 2015, Copyright by Erin Rose Ryan 2015

    79-15   Ana L. Quaresma, Is CFD an efficient tool to develop pool type fishways? International Conference on Engineering and Ecohydrology for Fish Passage. Paper 20, June 24, 2015

    78-15   Amir Alavi, Don Murray, Claude Chartrand and Derek McCoy, CFD Modeling Provides Value Engineering, Hydro Review, October 2015

    75-15   Rebekka Czerny, Classification of flow patterns in a nature-oriented fishway based on 3D hydraulic simulation results, International Conference on Engineering and Ecohydrology for Fish Passage. Paper 39, June 22, 2015

    73-15   Frank Seidel, Hybrid model approach for designing fish ways – example fish lift system at Baldeney/Ruhr and fishway at Geesthacht /Elbet, International Conference on Engineering and Ecohydrology for Fish Passage 2015

    72-15   G. Guyot, B. Huber, and A. Pittion-Rossillon, Assessment of a numerical method to forecast vortices with a scaled model, E-proceedings of the 36th IAHR World Congress, 28 June – 3 July, 2015, The Hague, the Netherlands

    71-15   Abbas Parsaie, Amir Hamzeh Haghiabi and Amir Moradinejad, CFD modeling of flow pattern in spillway’s approach channel, Sustainable Water Resources Management, September 2015, Volume 1, Issue 3, pp 245-251

    70-15   T. Liepert, A. Kuhlmann, G. Haimer, M.D. Bui and P. Rutschmann, Optimization of Fish Pass Entrance Location at a Hydropower Plant Considering Site-Specific Constraints, Proceedings of the 14th International Conference on Environmental Science and Technology, Rhodes, Greece, 3-5 September 2015

    67-15   Alkistis Stergiopoulou and Efrossini Kalkani, Towards a first CFD study of modern horizontal axis Archimedean water current turbines, Volume: 02 Issue: 04, ISO 9001:2008 Certified Journal © 2015, IRJET, July 2015

    66-15   Won Choi, Jeongbae Jeon, Jinseon Park, Jeong Jae Lee and Seongsoo Yoon, System reliability analysis of downstream spillways based on collapse of upstream spillways, Int J Agric & Biol Eng, 2015; 8(4): 140-150.

    64-15   Szu-Hsien Peng and Chuan Tang, Development and Application of Two-Dimensional Numerical Model on Shallow Water Flows Using Finite Volume Method, Journal of Applied Mathematics and Physics, 2015, 3, 989-996, Published Online August 2015 in SciRes. http://www.scirp.org/journal/jamp, http://dx.doi.org/10.4236/jamp.2015.38121

    62-15   Cuneyt Yavuz, Ali Ersin Dincer, Kutay Yilmaz and Samet Dursun, Head Loss Estimation of Water Jets from Flip Bucket of Cakmak-1 Diversion Weir and HEPP, RESEARCH GATE, August 2015 DOI: 10.13140/RG.2.1.3650.5440

    54-15   Guo-bin Xu, Li-na Zhao, and Chih Ted Yang, Derivation and verification of minimum energy dissipation rate principle of fluid based on minimum entropy production rate principle, International Journal of Sediment Research, August 2015

    50-15   Vafa Khoolosi, Sedat Kabdaşli, and Sevda Farrokhpour, Modeling and Comparison of Water Waves Caused by Landslides into Reservoirs, Watershed Management 2015 © ASCE 2015.

    48-15   Mohammad Rostami and Maaroof Siosemarde, Human Life Saving by Simulation of Dam Break using FLOW-3D (A Case Study: Upper Gotvand Dam), www.sciencejournal.in, Volume- 4 Issue- 3 (2015) ISSN: 2319–4731 (p); 2319–5037 (e) © 2015 DAMA International. All rights reserved.

    47-15   E. Kolden, B. D. Fox, B. P. Bledsoe and M. C. Kondratieff, Modelling Whitewater Park Hydraulics and Fish Habitat in Colorado, River Res. Applic., doi: 10.1002/rra.2931, 2015

    43-15   Firouz Ghasemzadeh, Behzad Parsa, and Mojtaba Noury, Numerical Study of Overflow Capacity of Spillways, E-proceedings of the 36th IAHR World Congress, 28 June – 3 July, 2015, The Hague, the Netherlands

    42-15   Mario Oertel, Numerical Modeling of Free-Surface Flows in Practical Applications, Chapter 8 in Rivers – Physical, Fluvial and Environmental Processes (GeoPlanet: Earth and Planetary Sciences), by Pawel Rowiński and Artur Radecki-Pawlik, July 2, 2015

    39-15   R. Gabl, J. Seibl, B. Gems, and M. Aufleger, 3-D-numerical approach to simulate an avalanche impact into a reservoir, Nat. Hazards Earth Syst. Sci. Discuss., 3, 4121–4157, 2015, www.nat-hazards-earth-syst-sci-discuss.net/3/4121/2015/, doi:10.5194/nhessd-3-4121-2015, © Author(s) 2015. CC Attribution 3.0 License.

    37-15   Mario Oertel, Discharge Coefficients of Piano Key Weirs from Experimental and Numerical Models, E-proceedings of the 36th IAHR World Congress, 28 June – 3 July, 2015, The Hague, the Netherlands

    36-15   Jessica Klein and Mario Oertel, Comparison between Crossbar Block Ramp and Vertical Slot Fish Pass via Numerical 3D CFD Simulation, E-proceedings of the 36th IAHR World Congress, 28 June – 3 July, 2015, The Hague, the Netherlands

    35-15   Mario Oertel, Jan P. Balmes and Daniel B. Bung, Numerical Simulation of Erosion Processes on Crossbar Block Ramps, E-proceedings of the 36th IAHR World Congress, 28 June – 3 July, 2015, The Hague, the Netherlands

    33-15   Daniel Valero and Daniel B. Bung, Hybrid Investigation of Air Transport Processes in Moderately Sloped Stepped Spillway Flows, E-proceedings of the 36th IAHR World Congress, 28 June – 3 July, 2015, The Hague, the Netherlands

    32-15   Deniz Velioglu, Nuray Denli Tokyay, and Ali Ersin Dincer, A Numerical and Experimental Study on the Characteristics of Hydraulic Jumps on Rough Beds, E-proceedings of the 36th IAHR World Congress, 28 June – 3 July, 2015, The Hague, the Netherlands

    31-15   J.C.C. Amorim, R.C.R. Amante, and V.D. Barbosa, Experimental and Numerical Modeling of Flow in a Stilling Basin, E-proceedings of the 36th IAHR World Congress, 28 June – 3 July, 2015, The Hague, the Netherlands

    30-15   Luna B.J. César, Salas V. Christian, Gracia S. Jesús, and Ortiz M. Victor, Comparative Analysis of the Modification of Turbulence and Its Effects on a Trapezoidal Section Stilling Basin, E-proceedings of the 36th IAHR World Congress, 28 June – 3 July, 2015, The Hague, the Netherlands

    27-15   L. Castillo, J. Carrillo, and M. Álvarez, Complementary Methods for Determining the Sedimentation and Flushing in a Reservoir, J. Hydraul. Eng., 10.1061/(ASCE)HY.1943-7900.0001050 , 05015004, 2015.

    22-15   Mohammad Vaghefi, Mohammad Shakerdargah and Maryam Akbari, Numerical investigation of the effect of Froude number on flow pattern around a submerged T-shaped spur dike in a 90º bend, © Turkish Journal of Engineering & Environmental Sciences, 03.04.2015, doi:10.3906/muh-1405-2

    18-15   S. Michael Scurlock, Amanda L. Cox, Drew C. Baird, Christopher I. Thornton and Steven R. Abt, Hybrid Modeling of River Training Structures in Sinuous Channels, SEDHYD 2015, Joint 10th Federal Interagency Sedimentation Conference, 5th Federal Interagency Hydrologic Modeling Conference, April 19-23, 2015, Reno, Nevada

    13-15   Selahattin Kocaman and Hatice Ozmen-Cagatay, Investigation of dam-break induced shock waves impact on a vertical wall, Journal of Hydrology (2015), doi: http://dx.doi.org/10.1016/j.jhydrol.2015.03.040.

    12-15   Nguyen Cong Thanh and Wang Ling-Ling, Physical and Numerical Model of Flow through the Spillways with a Breast Wall, KSCE Journal of Civil Engineering (0000) 00(0):1-8, Copyright 2015 Korean Society of Civil Engineers, DOI 10.1007/s12205-015-0742-0, April 10, 2015.

    10-15   Yueping Yin, Bolin Huang, Guangning Liu and Shichang Wang, Potential risk analysis on a Jianchuandong dangerous rockmass-generated impulse wave in the Three Gorges Reservoir, China, Environ Earth Sci, DOI 10.1007/s12665-015-4278-x, © Springer-Verlag Berlin Heidelberg 2015

    08-15   Yue-ping Yin, Bolin Huang, Xiaoting Chen, Guangning Liu and Shichang Wang, Numerical analysis on wave generated by the Qianjiangping landslide in Three Gorges Reservoir, China, 10.1007/s10346-015-0564-7, © Springer-Verlag Berlin Heidelberg 2015

    07-15   M. Vaghefi, A. Ahmadi and B. Faraji, The Effect of Support Structure on Flow Patterns Around T-Shape Spur Dike in 90° Bend Channel, Arabian Journal for Science and Engineering, February 2015,

    06-15   Sajjad Mohammadpour Zalaki, Hosein Fathian, Ebrahim Zalaghi and Farhad Kalantar Hormozi, Investigation of hydraulic parameters and cavitation in Kheir Abad flood release structure, Canadian Journal of Civil Engineering, February 2015

    04-15  Der-Chang Lo, Jin-Shuen Liou, and Shyy Woei Chang, Hydrodynamic Performances of Air-Water Flows in Gullies with and without Swirl Generation Vanes for Drainage Systems of Buildings, Water 2015, 7(2), 679-696; doi:10.3390/w7020679

    01-15   William Daley Clohan, Three-Dimensional Numerical Simulations of Subaerial Landslide Generated Waves, Master’s Thesis: Civil Engineering, The University of British Columbia (Vancouver), January 2015 © William Daley Clohan, 2015. Available upon request.

    136-14   Charles R. Ortloff, Hydraulic Engineering in 300 BCE- CE 300 Petra (Jordan), Encyclopedia of Ancient Science, Technology and Medicine in Nonwestern Cultures, Springer Publishing, Berlin Germany, 2014.

    135-14   Charles R. Ortloff, Land, Labor, Water and Technology in Precolumbian South America, Encyclopedia of Ancient Science, Technology and Medicine in Nonwestern Cultures, Springer Publishing, Berlin Germany, 2014.

    134-14   Charles R. Ortloff, Hydrologic Engineering of the 300 BCE- CE 1100 Precolumbian Tiwanaku State (Bolivia), Encyclopedia of Ancient Science, Technology and Medicine in Nonwestern Cultures, Springer Publishing, Berlin Germany, 2014.

    133-14   Charles R. Ortloff, Water engineering at Petra (Jordan): Recreating the decision process underlying hydraulic engineering of the Wadi Mataha pipeline system, Journal of Archaeological Science, April 2014. 44. 91–97. 10.1016/j.jas.2014.01.015.

    132-14   Charles R. Ortloff, Hydraulic Engineering in Ancient Peru and Bolivia, Encyclopedia of Ancient Science, Technology and Medicine in Nonwestern Cultures, Springer Publishing, Berlin Germany, 2014.

    131-14    Charles R. Ortloff, Water Management in Ancient Peru, Living Reference Work Entry, Encyclopedia of Ancient Science, Technology and Medicine in Nonwestern Cultures, Springer Publishing, Berlin Germany, 2014.

    130-14  Kordula Schwarzwälder and Peter Rutschmann, Sampling bacteria with a laser, Geophysical Research Abstracts Vol. 16, EGU2014-15144, 2014 EGU General Assembly 2014 © Author(s) 2014. CC Attribution 3.0 License.

    129-14   Kordula Schwarzwälder, Eve Walters and Peter Rutschmann, Bacteria fate and transport in a river, Geophysical Research Abstracts Vol. 16, EGU2014-14022, 2014 EGU General Assembly 2014 © Author(s) 2014. CC Attribution 3.0 License.

    127-14   Charles R. Ortloff, Hydraulic Engineering in Petra, Living Reference Work Entry, Encyclopedia of the History of Science, Technology, and Medicine in Non-Western Cultures, pp 1-13, 03 July 2014

    124-14  G. Wei. M. Grünzner and F. Semler, Combination of 2D shallow water and full 3D numerical modeling for sediment transport in reservoirs and basins, Reservoir Sedimentation – Schleiss et al. (Eds) © 2014 Taylor & Francis Group, London, ISBN 978-1-138-02675-9.

    121-14    A. Bayón-Barrachina, D. Valero, F. Vallès-Morán, and P.A. López-Jiménez, Comparison of CFD Models for Multiphase Flow Evolution in Bridge Scour Processes, 5th International Junior Researcher and Engineer Workshop on Hydraulic Structures, Spa, Belgium, 28-30 August 2014

    120-14  D. Valero, R. García-Bartual and J. Marco, Optimisation of Stilling Basin Chute Blocks Using a Calibrated Multiphase RANS Model, 5th International Junior Researcher and Engineer Workshop on Hydraulic Structures, Spa, Belgium, 28-30 August 2014

    119-14   R. Gabl, B. Gems, M. Plörer, R. Klar, T. Gschnitzer, S. Achleitner, and M. Aufleger, Numerical Simulations in Hydraulic Engineering, Computational Engineering, 2014, pp 195-224, April 2014

    118-14  Kerilyn Ambrosini, Analysis of Flap Gate Design and Implementations for Water Delivery Systems in California and Nevada, BioResource and Agricultural Engineering, BioResource and Agricultural Engineering Department, California Polytechnic State University, San Luis Obispo, 2014

    117-14  Amir Moradinejad, Abas Parssai, Mohamad Noriemamzade, Numerical Modeling of Flow Pattern In Kamal Saleh Dam Spillway Approach Channel, App. Sci. Report.10 (2), 2014: 82-89, © PSCI Publications

    116-14  Luis G. Castillo and José M. Carrillo, Characterization of the Dynamic Actions and Scour Estimation Downstream of a Dam, 1st International Seminar on Dam Protection against Overtopping and Accidental Leakage, M.Á. Toledo, R. Morán, E. Oñate (Eds), Madrid, 24-25 November 2014

    115-14  Luis G. Castillo, José M. Carrillo, Juan T. García, Antonio Vigueras-Rodríguez, Numerical Simulations and Laboratory Measurements in Hydraulic Jumps, 11th International Conference on Hydroinformatics, HIC 2014, New York City, USA

    114-14  Du Han Lee, Young Joo Kim, and Samhee Lee, Numerical modeling of bed form induced hyporheic exchangePaddy and Water Environment, August 2014, Volume 12, Issue 1 Supplement, pp 89-97

    112-14  Ed Zapel, Hank Nelson, Brian Hughes, Steve Fry, Options for Reducing Total Dissolved Gas at the Long Lake Hydroelectric Facility, Hydrovision International, July 22-24, 2014, Nashville, TN

    111-14  Jason Duguay, Jay Lace, Dave Penny and Ken Hannaford, Evolution of an Innovative Fish Ladder Design to Address Issues of Perched Culverts, 2014 Conference of the Transportation Association of Canada, Montreal, Quebec

    106-14   Manuel Gomez and Eduardo Martinez, 1D, 2D and 3D Modeling of a PAC-UPC Laboratory Canal Bend, SimHydro 2014: Modelling of rapid transitory flows, 11-13 June 2014, Sophia Antipolis

    105-14 Jason Duguay and Jay Lacey, Numerical Validation of an Innovative Fish Baffle Design in Response to Fish Passage Issues at Perched Culverts, CSPI Technical Bulletin, January 14, 2014

    104-14  Di Ning, Di,  A Computational Study on Hydraulic Jumps, including Air Entrainment, Master’s Thesis: Civil and Environmental Engineering, University of California, Davis, 2014, 1569799, Copyright ProQuest, UMI Dissertations Publishing 2014

    103-14  S. M. Sayah, S. Bonanni, Ph. Heller, and M. Volpato, Physical and Numerical Modelling of Cerro del Águila Dam -Hydraulic and Sedimentation, DOI: 10.13140/2.1.5042.1122 Conference: Hydro 2014

    102-14   Khosrow Hosseini, Shahab Rikhtegar, Hojat Karami, Keivan Bina, Application of Numerical Modeling to Assess Geometry Effect of Racks on Performance of Bottom Intakes, Arabian Journal for Science and Engineering, December 2014

    98-14  Aysel Duru, Numerical Modelling of Contracted Sharp Crested Weirs, Master’s Thesis: The Graduate School of Natural and Applied Sciences of Middle East Technical University, November 2014

    97-14  M Angulo, S Liscia, A Lopez and C Lucino, Experimental validation of a low-head turbine intake designed by CFD following Fisher and Franke guidelines, 27th IAHR Symposium on Hydraulic Machinery and Systems (IAHR 2014), IOP Publishing, IOP Conf. Series: Earth and Environmental Science 22 (2013) 042014 doi:10.1088/1755-1315/22/4/042014

    94-14   Hamidreza Babaali, Abolfazl Shamsai, and Hamidreza Vosoughifar, Computational Modeling of the Hydraulic Jump in the Stilling Basin with ConvergenceWalls Using CFD Codes, Arab J Sci Eng, DOI 10.1007/s13369-014-1466-z, October 2014

    93-14   A.J. Vellinga, M.J.B. Cartigny, J.T. Eggenhuisen, E.W.M. Hansen, and R. Rouzairol, Morphodynamics of supercritical-flow bedforms using depth-resolved computational fluid dynamics model, International Association of Sedimentologists, Geneva, 2014.

    88-14   Marcelo A. Somos-Valenzuela, Rachel E. Chisolm, Daene C. McKinney, and Denny Rivas, Inundation Modeling of a Potential Glacial Lake Outburst Flood in Huaraz, Peru, CRWR Online Report 14-01, March 2014

    84-14   Hossein Shahheydari, Ehsan Jafari Nodoshan, Reza Barati, and Mehdi Azhdary Moghadam, Discharge coefficient and energy dissipation over stepped spillway under skimming flow regimeKSCE Journal of Civil Engineering, 10.1007/s12205-013-0749-3, November 2014

    81-14   Gaël Epely-Chauvin, Giovanni De Cesare and Sebastian Schwindt, Numerical Modelling of Plunge Pool Scour Evolution in Non-Cohesive Sediments, Engineering Applications of Computational Fluid Mechanics Vol. 8, No. 4, pp. 477–487 (2014).

    79-14   Liquan Xie, Yanhui Xu, and Wenrui Huang, Numerical Study on Hydrodynamic Mechanism of Sediment Trapping by Geotextile Mattress with Sloping Curtain (GMSC), Proceedings of the Eleventh (2014) Pacific/Asia Offshore Mechanics Symposium Shanghai, China, October 12-16, 2014 Copyright © 2014 by The International Society of Offshore and Polar Engineers, ISBN 978–1 880653 90-6: ISSN 1946-004X.

    78-14  D. N. Powell and A. A. Khan, Flow Field Upstream of an Orifice under Fixed Bed and Equilibrium Scour ConditionsJ. Hydraul. Eng., 10.1061/(ASCE)HY.1943-7900.0000960, 04014076, 2014.

    76-14   Berk Sezenöz, Numerical Modelling of Continuous Transverse Grates for Hydraulic Efficiency, Master’s Thesis: The Graduate School of Natural and Applied Sciences of Middle East Technical University, October 2014

    75-14   Francesco Calomino and Agostino Lauria, 3-D Underflow of a Sluice Gate at a Channel Inlet; Experimental Results and CFD Simulations, Journal of Civil Engineering and Urbanism, Volume 4, Issue 5: 501-508 (2014)

    73-14   Som Dutta, Talia E. Tokyay, Yovanni A. Cataño-Lopera, Sergio Serafinod and Marcelo H. Garcia, Application of computational fluid dynamic modeling to improve flow and grit transport in Terence J. O’Brien Water Reclamation Plant, Chicago, Illinois, Journal of Hydraulic Research, DOI: 10.1080/00221686.2014.949883, October 2014

    72-14   Ali Heidari, Poria Ghassemi, Evaluation of step’s slope on energy dissipation in stepped spillway, International Journal of Engineering & Technology, 3 (4) (2014) 501-505, ©Science Publishing Corporation, www.sciencepubco.com/index.php/IJET, doi: 10.14419/ijet.v3i4.3561

    70-14   M. Tabatabai, M. Heidarnejad, A. Bordbar, Numerical Study of Flow Patterns in Stilling Basin with Sinusoidal Bed using FLOW-3D Model, Advances in Environmental Biology, 8(13) August 2014, Pages: 787-792

    66-14   John S. Schwartz, Keil J. Neff, Frank E. Dworak, Robert R. Woockman, Restoring riffle-pool structure in an incised, straightened urban stream channel using an ecohydraulic modeling approach, Ecol. Eng. (2014), doi.org/10.1016/j.ecoleng.2014.06.002

    65-14  Laura Rozumalski and Michael Fullarton, CFD Modeling to Design a Fish Lift Entrance, Hydro Review, July 2014

    64-14   Pam Waterman, Scaled for Success: Computational Fluid Dynamics Analysis Prompts Swift Stormwater System Improvements in Indianapolis, WaterWorld, August 2014.

    63-14   Markus Grünzner and Peter Rutschmann, Large Eddy Simulation  – Ein Beitrag zur Auflösung turbulenter Strömungsstrukturen in technischen Fischaufstiegshilfen; (LES – resolving turbulent flow in technical fish bypasses), Tagungsband Internationales Symposium in Zurich, Wasser- und Flussbau im Alpenraum, Versuchsanstalt fur Wasserbau, Hydrologie und Glaziologie, ETH Zurich. In German.

    62-14   Jason Duguay, Jay Lace, Dave Penny, and Ken Hannaford, Evolution of an Innovative Fish Ladder Design to Address Issues of Perched Culverts, 2014 Conference of the Transportation Association of Canada, Montreal, Quebec

    60-14   Kordula Schwarzwälder, Minh Duc Bui, and Peter Rutschmann, Simulation of bacteria transport processes in a river with FLOW-3D, Geophysical Research Abstracts, Vol. 16, EGU2014-12993, 2014, EGU General Assembly 2014, © Author(s) 2014. CC Attribution 3.0 License.

    58-14   Eray Usta, Numercial Investigation of Hydraulic Characteristics of Laleili Dam Spillway and Comparison with Physical Model Study, Master’s Thesis: The Graduate School of Natural and Applied Sciences of Middle East Technical University, May 2014

    57-14   Selahattin Kocaman, Prediction of Backwater Profiles due to Bridges in a Compound Channel Using CFD, Hindawi Publishing Corporation, Advances in Mechanical Engineering, Volume 2014, Article ID 905217, 9 pages, http://dx.doi.org/10.1155/2014/905217

    54-14   Ines C. Meireles, Fabian A. Bombardelli, and Jorge Matos, Air entrainment onset in skimming flows on steep stepped spillways: an analysis, (2014) Journal of Hydraulic Research, 52:3, 375-385, DOI: 10.1080/00221686.2013.878401

    53-14   Charles R Ortloff, Groundwater Management in the 300 bce-1100ce Pre-Columbian City of Tiwanaku (Bolivia), Hydrol Current Res 5: 168. doi:10.4172/2157-7587.1000168, 2014

    50-14   Mohanad A. Kholdier, Weir-Baffled Culvert Hydrodynamics Evaluation for Fish Passage using Particle Image Velocimetry and Computational Fluid Dynamic Techniques, Ph.D. Thesis: Utah State University (2014). All Graduate Theses and Dissertations. Paper 3078. http://digitalcommons.usu.edu/etd/3078

    48-14   Yu-Heng Lin, Study on raceway pond for microalgae culturing system, Master Thesis: Department of Marine Environment and Engineering, National Sun Yat-sen University, August 2014. In Chinese

    38-14   David Ingram, Robin Wallacey, Adam Robinsonz and Ian Bryden, The design and commissioning of the first, circular, combined current and wave test basin, Proceedings of Oceans 2014 MTS/IEEE, Taipei, Taiwan, IEEE, April 2014

    36-14   Charles R. Ortloff, Hydraulic Engineering in Precolumbian Peru and Bolivia, The Encyclopedia of the History of Science, Technology and Medicine in Non-Western Cultures, Springer-Verlag, Volumes II and III, Heidelberg, Germany, 2014.

    35-14   Charles R. Ortloff, Hydraulic Engineering in BC 100- AD 300 Petra (Jordan), The Encyclopedia of the History of Science, Technology and Medicine in Non-Western Cultures, Springer-Verlag, Volumes II and III, Heidelberg, Germany, 2014.

    34-14   Charles R. Ortloff, Hydraulic Engineering in Precolumbian Peru and Bolivia, The Encyclopedia of the History of Science, Technology and Medicine in Non-Western Cultures, Springer-Verlag, Volumes II and III, Heidelberg, Germany, 2014.

    33-14   Roman Gabl, Bernhard Gems, Giovanni De Cesare, and Markus Aufleger, Contribution to Quality Standards for 3D-Numerical Simulations with FLOW-3D, Wasserwirtschaft (ISSN: 0043-0978), vol. 104, num. 3, p. 15-20, Wiesbaden: Springer Vieweg-Springer Fachmedien Wiesbaden Gmbh, 2014. Available for download at the University of Innsbruck. In German.

    31-14   E. Fadaei-Kermani and G.A. Barani, Numerical simulation of flow over spillway based on the CFD method, Scientia Iranica A, 21(1), 91-97, 2014

    30-14   Luis G. Castillo  and José M. Carrillo, Scour Analysis Downstream of Paute-Cardenillo Dam, © 3rd IAHR Europe Congress, Book of Proceedings, 2014, Porto, Portugal.

    29-14    L. G. Castillo, M. A. Álvarez, and J. M. Carrillo, Numerical modeling of sedimentation and flushing at the Paute-Cardenillo Reservoir, ASCE-EWRI. International Perspective on Water Resources and Environment Quito, January 8-10, 2014

    28-14   L. G. Castillo and J. M. CarrilloScour estimation of the Paute-Cardenillo Dam, ASCE-EWRI. International Perspective on Water Resources and Environment Quito, January 8-10, 2014.

    27-14   Luis G. Castillo, Manual A. Álvarez and José M. Carrillo, Analysis of Sedimentation and Flushing into the Reservoir Paute-Cardenillo© 3rd IAHR Europe Congress, Book of Proceedings, 2014, Porto, Portugal.

    24-14   Carter R. Newell and John Richardson, The Effects of Ambient and Aquaculture Structure Hydrodynamics on the Food Supply and Demand of Mussel Rafts, Journal of Shellfish Research, 33(1):257-272, DOI: http://dx.doi.org/10.2983/035.033.0125, 0125, 2014.

    16-14   Han Hu, Jiesheng Huang, Zhongdong Qian, Wenxin Huai, and Genjian Yu, Hydraulic Analysis of Parabolic Flume for Flow Measurement, Flow Measurement and Instrumentation, http://dx.doi.org/10.1016/j.flowmeasinst.2014.03.002, 2014.

    14-14   Seung Oh Lee, Sooyoung Kim, Moonil Kim, Kyoung Jae Lim and Younghun Jung, The Effect of Hydraulic Characteristics on Algal Bloom in an Artificial Seawater Canal: A Case Study in Songdo City, South Korea, Water 2014, 6, 399-413; doi:10.3390/w6020399, ISSN 2073-4441, www.mdpi.com/journal/water

    13-14   Kathryn Elizabeth Plymesser, Modeling Fish Passage and Energy Expenditure for American Shad in a Steeppass Fishway using Computational Fluid Dynamics, Ph.D. Thesis: Montana State University, January 2014, © Kathryn Elizabeth Plymesser, 2014, All Rights Reserved.

    12-14   Sangdo An and Pierre Y. Julien, Three-Dimensional Modeling of Turbid Density Currents in Imha Reservoir, J. Hydraul. Eng., 10.1061/(ASCE)HY.1943-7900.0000851, 05014004, 2014.

    09-14   B. Gems, M. Wörndl, R. Gabl, C. Weber, and M. Aufleger, Experimental and numerical study on the design of a deposition basin outlet structure at a mountain debris cone, Nat. Hazards Earth Syst. Sci., 14, 175–187, 2014, www.nat-hazards-earth-syst-sci.net/14/175/2014/, doi:10.5194/nhess-14-175-2014, © Author(s) 2014. CC Attribution 3.0 License.

    07-14   Charles R. Ortloff, Water Engineering at Petra (Jordan): Recreating the Decision Process underlying Hydraulic Engineering of the Wadi Mataha Pipeline System, Journal of Archaeological Science, Available online January 2014.

    06-14   Hatice Ozmen-Cagatay, Selahattin Kocaman, Hasan Guzel, Investigation of dam-break flood waves in a dry channel with a hump, Journal of Hydro-environment Research, Available online January 2014.

    05-14   Shawn P. Clark, Jonathan Scott Toews, and Rob Tkach, Beyond average velocity: Modeling velocity distributions in partially-filled culverts to support fish passage guidelines, International Journal of River Basin Management, DOI10.1080/15715124.2013.879591, January 2014.

    04-14   Giovanni De Cesare, Martin Bieri, Stéphane Terrier, Sylvain Candolfi, Martin Wickenhäuser and Gaël Micoulet, Optimization of a Shared Tailrace Channel of Two Pumped-Storage Plants by Physical and Numerical Modeling, Advances in Hydroinformatics Springer Hydrogeology 2014, pp 291-305.

    03-14   Grégory Guyot, Hela Maaloul and Antoine Archer, A Vortex Modeling with 3D CFD, Advances in Hydroinformatics Springer Hydrogeology 2014, pp 433-444.

    02-14   Géraldine Milési and Stéphane Causse, 3D Numerical Modeling of a Side-Channel Spillway, Advances in Hydroinformatics Springer Hydrogeology 2014, pp 487-498.

    01-14   Mohammad R. Namaee, Mohammad Rostami, S. Jalaledini and Mahdi Habibi, A 3-Dimensional Numerical Simulation of Flow Over a Broad-Crested Side Weir, Advances in Hydroinformatics, Springer Hydrogeology 2014, pp 511-523.

    104-13   Alireza Nowroozpour, H. Musavi Jahromi and A. Dastgheib, Studying different cases of wedge shape deflectors on energy dissipation in flip bucket using CFD model, Proceedings, 6th International Perspective on Water Resources & the Environment Conference (IPWE), Izmir, Turkey, January 7-9, 2013.

    102-13   Shari Dunlop, Isaac Willig and Roger L. Kay, Emergency Response to Erosion at Fort Peck Spillway: Hydraulic Analysis and Design, ICOLD 2013 International Symposium, Seattle, WA.

    101-13   Taeho Kang and Heebeom Shin, Dam Emergency Action Plans in Korea, ICOLD 2013 International Symposium, Seattle, WA.

    100-13   John Hess, Jeffrey Wisniewski, David Neff and Mike Forrest, A New Auxiliary Spillway for Folsom Dam, ICOLD 2013 International Symposium, Seattle, WA.

    98-13   Neda Sharif and Amin Rostami Ravori, Experimental and Numerical Study of the Effect of Flow Separation on Dissipating Energy in Compound Bucket, 2013 5th International Conference on Chemical, Biological and Environmental Engineering (ICBEE 2013); 2013 2nd International Conference on Civil Engineering (ICCEN 2013)

    97-13  A. Stergiopoulou, V. Stergiopoulos, and E. Kalkani, Contributions to the Study of Hydrodynamic Behaviour of Innovative Archimedean Screw Turbines Recovering the Hydropotential of Watercourses and of Coastal Currents, Proceedings of the 13th International Conference on Environmental Science and Technology Athens, Greece, 5-7 September 2013

    96-13   Shokry Abdelaziz, Minh Duc Bui, Namihira Atsushi, and Peter Rutschmann, Numerical Simulation of Flow and Upstream Fish Movement inside a Pool-and-Weir Fishway, Proceedings of 2013 IAHR World Congress, Chengdu, China

    95-13  Guodong Li, Lan Lang, and Jian Ning, 3D Numerical Simulation of Flow and Local Scour around a Spur Dike, Proceedings of 2013 IAHR World Congress, Chengdu, China

    93-13   Matthew C. Kondratieff and Eric E. Richer, Stream Habitat Investigations and Assistance, Federal Aid Project F-161-R19, Federal Aid in Fish and Wildlife Restoration, Job Progress Report, Colorado Parks & Wildlife, Aquatic Wildlife Research Section, Fort Collins, Colorado, August 2013. Available upon request

    92-13   Matteo Tirindelli, Scott Fenical and Vladimir Shepsis, State-of-the-Art Methods for Extreme Wave Loading on Bridges and Coastal Highways, Seventh National Seismic Conference on Bridges and Highways (7NSC), May 20-22, 2013, Oakland, CA

    91-13   Cecia Millán Barrera, Víctor Manuel Arroyo Correa, Jorge Armando Laurel Castillo, Modeling contaminant transport with aerobic biodegradation in a shallow water body, Proceedings of 2013 IAHR Congress © 2013 Tsinghua University Press, Beijing

    80-13  Brian Fox, Matthew Kondratieff, Brian Bledsoe, Christopher Myrick, Eco-Hydraulic Evaluation of Whitewater Parks as Fish Passage Barriers, International Conference on Engineering and Ecohydrology for Fish Passage, June 25-27, 2013, Oregon State University. Presentation available for download on the Scholarworks site.

    79-13  Changsung Kim, Jongtae Kim, Joongu Kang, Analysis of the Cause for the Collapse of a Temporary Bridge Using Numerical Simulation, Engineering, 2013, 5, 997-1005, (http://www.scirp.org/journal/eng), Copyright © 2013 Changsung Kim et al. Published Online December 2013

    76-13   Riley J. Olsen, Michael C. Johnson, and Steven L. Barfuss, Low-Head Dam Reverse Roller Remediation Options, Journal of Hydraulic Engineering, November 2013; doi:10.1061/(ASCE)HY.1943-7900.0000848.

    72-13  M. Pfister, E. Battisacco, G. De Cesare, and A.J. Schleiss, Scale effects related to the rating curve of cylindrically crested Piano Key weirs, Labyrinth and Piano Key Weirs II – PKW 2013 – Erpicum et al. (eds), © 2014 Taylor & Francis Group, London, ISBN 978-1-138-00085-8.

    71-13  F. Laugier, J. Vermeulen, and V. Lefebvre, Overview of Piano KeyWeirs experience developed at EDF during the past few years, Labyrinth and Piano Key Weirs II – PKW 2013 – Erpicum et al. (eds), © 2014 Taylor & Francis Group, London, ISBN 978-1-138-00085-8.

    70-13   G.M. Cicero, J.R. Delisle, V. Lefebvre, and J. Vermeulen, Experimental and numerical study of the hydraulic performance of a trapezoidal Piano Key weir, Labyrinth and Piano Key Weirs II – PKW 2013 – Erpicum et al. (eds, © 2014 Taylor & Francis Group, London, ISBN 978-1-138-00085-8.

    69-13   V. Lefebvre, J. Vermeulen, and B. Blancher, Influence of geometrical parameters on PK-Weirs discharge with 3D numerical analysis, Labyrinth and Piano Key Weirs II – PKW 2013 – Erpicum et al. (eds), © 2014 Taylor & Francis Group, London, ISBN 978-1-138-00085-8.

    65-13 Alkistis Stergiopoulou and Efrossini Kalkani, Towards a First CFD Study of Innovative Archimedean Inclined Axis Hydropower Turbines, International Journal of Engineering Research & Technology (IJERT), ISSN: 2278-0181, Vol. 2 Issue 9, September 2013.

    58-13  Timothy Sassaman, Andrew Johansson, Ryan Jones, and Marianne Walter, Hydraulic Analysis of a Pumped Storage Pond Using Complementary Methods, Hydrovision 2013 Conference Proceedings, Denver, CO, July 2013.

    57-13  Jose Vasquez, Kara Hurtig, and Brian Hughes, Computational Fluid Dynamics (CFD) Modeling of Run-of-River Intakes, Hydrovision 2013 Conference Proceedings, Denver, CO July 2013.

    56-13  David Souders, Jayesh Kariya, and Jeff Burnham, Validation of a Hybrid 3-Dimensional and 2-Dimensional Flow Modeling Technique for an Instanenous Dam-Break, Hydrovision 2013 Conference Proceedings, Denver, CO July 2013.

    55-13  Keith Moen, Dan Kirschbaum, Joe Groeneveld, Steve Smith and Kimberly Pate, Sluiceway Deflector Design as part of the Boundary TDG Abatement Program, Hydrovision 2013 Conference Proceedings, Denver, CO, July 2013.

    54-13  S. Temeepattanapongsa, G. P. Merkley, S. L. Barfuss and B. Smith, Generic unified rating for Cutthroat flumes, Irrig Sci, DOI 10.1007/s00271-013-0411-3, Springer-Verlag Berlin Heidelberg 2013, August 2013.

    53-13 Hossein Afshar and Seyed Hooman Hoseini, Experimental and 3-D Numerical Simulation of Flow over a Rectangular Broad-Crested Weir, International Journal of Engineering and Advanced Technology (IJEAT), ISSN: 2249-8958, Volume 2, Issue 6, August 2013

    52-13  Abdulmajid Matinfard (Kabi), Mohammad Heidarnejad, Javad Ahadian, Effect of Changes in the Hydraulic Conditions on the Velocity Distribution around a L-Shaped Spur Dike at the River Bend, Technical Journal of Engineering and Applied Sciences Available online at www.tjeas.com ©2013 TJEAS Journal-2013-3-16/1862-1868 ISSN 2051-0853 ©2013 TJEAS

    51-13  Elham Radaei, Sahar Nikbin, and Mahdi Shahrokhi, Numerical Investigation of Angled Baffle on the Flow Pattern in a Rectangular Primary Sedimentation Tank, RCEE, Research in Civil and Environmental Engineering 1 (2013) 79-91.

    48-13   Mohammad Kayser, Mohammed A. Gabr, Assessment of Scour on Bridge Foundations by Means of In Situ Erosion Evaluation Probe, Transportation Research Record: Journal of the Transportation Research Board, 0361-1981 (Print), Volume 2335 / 2013, pp 72-78. 10.3141/2335-08, August 2013.

    47-13  Wei Ping Yin et al., 2013, Three-Dimensional Water Temperature and Hydrodynamic Simulation of Xiangxi River Estuary, Advanced Materials Research, 726-731, 3212, August, 2013.

    41-13   N. Nekoue, R. Mahajan, J. Hamrick, and H. Rodriguez, Selective Withdrawal Hydraulic Study Using Computational Fluid Dynamics Modeling, World Environmental and Water Resources Congress 2013: pp. 1808-1813. doi: 10.1061/9780784412947.177.

    40-13  Eleanor Kolden, Modeling in a three-dimensional world: whitewater park hydraulics and their impact on aquatic habitat in Colorado, Thesis: Master of Science, Civil and Environmental Engineering, Colorado State University. Full thesis available online at Colorado State University.

    38-13  Prashant Huddar P.E. and Yashodhan Dhopavkar, CFD Use in Water – Insight, Foresight, and Efficiency, CFD Application in Water Engineering, Bangalore, India, June 2013.

    37-13 B. Gems, M. Wörndl, R. Gabl, C. Weber, and M. Aufleger, Experimental and numerical study on the design of a deposition basin outlet structure at a mountain debris cone, Nat. Hazards Earth Syst. Sci. Discuss., 1, 3169–3200, 2013, www.nat-hazards-earth-syst-sci-discuss.net/1/3169/2013/, doi:10.5194/nhessd-1-3169-2013, © Author(s) 2013. Full paper online at: Natural Hazards and Earth System Sciences.

    33-13   Tian Zhou and Theodore A. Endreny, Reshaping of the hyporheic zone beneath river restoration structures: Flume and hydrodynamic experiments, Water Resources Research, DOI: 10.1002/wrcr.20384, ©2013. American Geophysical Union. All Rights Reserved.

    31-13  Francesco Calomino and Agostino Lauria, MOTO ALL’IMBOCCO DI UN CANALE RETTANGOLARE CONTROLLATO DA PARATOIA PIANA. Analisi sperimentale e modellazione numerica 3DFLOW AT THE INTAKE OF THE RECTANGULAR CHANNEL ;CONTROLLED BY A FLAT SLUICE GATE. Experimental and Numerical 3D ModelL’acqua, pp. 29-36, © Idrotecnica Italiana, 2013. In Italian and English.

    30-13  Vinod V. Nair and S.K. Bhattacharyya, Numerical Study of Water Impact of Rigid Sphere under the Action of Gravity CFD Application in Water Engineering, Bangalore, India, June 2013. Abstract only.

    29-13   Amar Pal Singh, Faisal Bhat, Ekta Gupta, 3-D Spillway Simulations of Ratle HEP (J&K) for the Assessment of Design Alternatives to be Tested in Model Studies, CFD Application in Water Engineering, Bangalore, India, June 2013.

    28-13  Shun-Chung Tsung, Jihn-Sung Lai, and Der-Liang Young, Velocity distribution and discharge calculation at a sharp-crested weir, Paddy Water Environ, DOI 10.1007/s10333-013-0378-y, © Springer Japan 2013, May 2013.

    27-13  Karen Riddette and David Ho, Assessment of Spillway Modeling Using Computational Fluid DynamicsANCOLD Proceedings of Technical Groups, 2013.

    21-13  Tsung-Hsien Huang and Chyan-Deng Jan, Simulation of Velocity Distribution for Water Flow in a Vortex-Chamber-Type Sediment Extractor, EGU General Assembly 2013, held 7-12 April, 2013 in Vienna, Austria, id. EGU2013-7061. Online at: http://adsabs.harvard.edu/abs/2013EGUGA..15.7061H

    19-13  Riley J. Olsen, Hazard Classification and Hydraulic Remediation Options for Flat-Topped and Ogee-Crested Low- Head Dams, Thesis: Master of Science in Civil and Environmental Engineering, Utah State University, All Graduate Theses and Dissertations. Paper 1538. http://digitalcommons.usu.edu/etd/1538, 2013.

    17-13  Mohammad-Hossein Erfanain-Azmoudeh and Amir Abbas Kamanbedast, Determine the Appropriate Location of Aerator System on Gotvandolia Dam’s Spillway Using FLOW-3D, American-Eurasian J. Agric. & Environ. Sci., 13 (3): 378-383, 2013, ISSN 1818-6769, © IDOSI Publications, 2013.

    13-13   Chia-Cheng Tsai, Yueh-Ting Lin, and Tai-Wen Hsu, On the weak viscous effect of the reflection and transmission over an arbitrary topography, Phys. Fluids 25, 043103 (2013); http://dx.doi.org/10.1063/1.4799099 (21 pages).

    07-13  M. Kayser and M. A. Gabr, Scour Assessment of Bridge Foundations Using an In Situ Erosion Evaluation Probe (ISEEP), 92nd Transportation Research Board Annual Meeting, January 13-17, 2013, Washington, D.C.

    06-13   Yovanni A. Cataño-Lopera, Blake J. Landry, Jorge D. Abad, and Marcelo H. García, Experimental and Numerical Study of the Flow Structure around Two Partially Buried Objects on a Deformed Bed, Journal of Hydraulic Engineering © ASCE /March 2013, 269-283.

    04-13  Safinaz El-Solh, SPH Modeling of Solitary Waves and Resulting Hydrodynamic Forces on Vertical and Sloping Walls, Thesis: Master of Applied Science in Civil Engineering, Department of Civil Engineering, University of Ottawa, October 2012, © Safinaz El-Solh, Ottawa, Canada, 2013. Full paper available online at uOttawa.

    108-12  Hatice Ozmen-Cagatay and Selahattin Kocaman, Investigation of Dam-Break Flow Over Abruptly Contracting Channel With Trapezoidal-Shaped Lateral Obstacles, Journal of Fluids Engineering © 2012 by ASME August 2012, Vol. 134 / 081204-1

    102-12 B.M. Crookston, G.S. Paxson, and B.M. Savage, Hydraulic Performance of Labryinth Weirs for High Headwater Ratios, 4th IAHR International Symposium on Hydraulic Structures, 9-11 February 2012, Porto, Portugal, ISBN: 978-989-8509-01-7.

    101-12 Jungseok Ho and Wonil Kim, Discrete Phase Modeling Study for Particle Motion in Storm Water Retention, KSCE Journal of Civil Engineering (2012) 16(6):1071-1078, DOI 10.1007/s12205-012-1304-3.

    99-12  Charles R. Ortloff and Michael E. Mosely, Environmental change at a Late Archaic period site in north central coast Perú, Ñawpa Pacha, Journal of Andean Archaeology, Volume 32, Number 2 / December 2012, ISSN: 0077-6297 (Print); 2051-6207 (Online), Left Coast Press, Inc.

    98-12  Tao Wang and Vincent H. Chu, Manning Friction in Steep Open-channel Flow, Seventh International Conference on Computational Fluid Dynamics (ICCFD7), Big Island, Hawaii, July 9-13, 2012.

    96-12  Zhi Yong Dong, Qi Qi Chen, Yong Gang, and Bin Shi, Experimental and Numerical Study of Hydrodynamic Cavitation of Orifice Plates with Multiple Triangular Holes, Applied Mechanics and Materials, Volumes 256-259, Advances in Civil Engineering, December 2012.

    95-12  Arjmandi H., Ghomeshi M.,  Ahadiayn J., and Goleij G., Prediction of Plunge Point in the Density Current using RNG Turbulence Modeling, Water and Soil Science (Agricultural Science) Spring 2012; 22(1):171-185. Abstract available online at the Scientific Online Database.

    84-12  Li Ping Zhao, Jian Qiu Zhang, Lei Chen, Xuan Xie, Jun Qiang Cheng, Study of Hydrodynamic Characteristics of the Sloping Breakwater of Circular Protective Facing, Advanced Materials Research (Volumes 588 – 589), Advances in Mechanics Engineering, 1781-1785, 10.4028/www.scientific.net/AMR.588-589.1781.

    83-12 Parviz Ghadimi, Abbas Dashtimanesh, and Seyed Reza Djeddi, Study of water entry of circular cylinder by using analytical and numerical solutions, J. Braz. Soc. Mech. Sci. & Eng. 2012, vol.34, n.3, pp. 225-232 . ISSN 1678-5878. http://dx.doi.org/10.1590/S1678-58782012000300001.

    81-12  R. Gabl, S. Achleitner, A. Sendlhofer, T. Höckner, M. Schmitter and M. Aufleger, Side-channel spillway – Hybrid modeling, Hydraulic Measurements and Experimental Methods 2012, EWRI/ASCE, August 12-15, 2012, Snowbird, Utah.

    80-12  Akin Aybar, Computational Modelling of Free Surface Flow in Intake Structures using FLOW-3D Software, Thesis: MS in Civil Engineering, The Graduate School of Natural and Applied Sciences of Middle East Technical University, June 2012.

    74-12  Mahdi Shahrokhi, Fatemeh Rostami, Md Azlin Md Said, Saeed Reza Sabbagh Yazdi, and Syafalni Syafalni, Computational investigations of baffle configuration effects on the performance of primary sedimentation tanks, Water and Environment Journal, 22 October 2012, © 2012 CIWEM.

    68-12  Jalal Attari and Mohammad Sarfaraz, Transitional Steps Zone in Steeply Stepped Spillways, 9th International Congress on Civil Engineering, May 8-10, 2012, Isfahan University of Technology (IUT), Isfahan, Iran

    67-12  Mohammad Sarfaraz, Jalal Attari and Michael Pfister, Numerical Computation of Inception Point Location for Steeply Sloping Stepped Spillways, 9th International Congress on Civil Engineering, May 8-10, 2012, Isfahan University of Technology (IUT), Isfahan, Iran

    64-12  Anders Wedel Nielsen, Xiaofeng Liu, B. Mutlu Sumer, Jørgen Fredsøe, Flow and bed shear stresses in scour protections around a pile in a current, Coastal Engineering, Volume 72, February 2013, Pages 20–38.

    62-12  Ehab A. Meselhe, Ioannis Georgiou, Mead A. Allison, John A McCorquodale, Numerical Modeling of Hydrodynamics and Sediment Transport in Lower Mississippi at a Proposed Delta Building Diversion, Journal of Hydrology, October 2012.

    60-12  Markus Grünzner and Gerhard Haimerl, Numerical Simulation Downstream Attraction Flow at Danube Weir Donauwörth, 9th ISE 2012, Vienna, Austria.

    59-12 M. Grünzner, A 3 Dimensional Numerical (LES) and Physical ‘Golf Ball’ Model in Comparison to 1 Dimensional Approach, Hydraulic Measurements and Experimental Methods 2012, EWRI/ASCE, August 12-15, 2012, Snowbird, Utah

    58-12  Shawn P. Clark, Jonathan S. Toews, Martin Hunt and Rob Tkach, Physical and Numerical Modeling in Support of Fish Passage Regulations, 9th ISE 2012, Vienna, Austria.

    57-12  Mahdi Shahrokhi, Fatemeh Rostami, Md Azlin Md Said, Syafalni, Numerical Modeling of Baffle Location Effects on the Flow Pattern of Primary Sedimentation Tanks, Applied Mathematical Modelling, Available online October 2012, http://dx.doi.org/10.1016/j.apm.2012.09.060.

    50-12  Gricelda Ramirez, A Virtual Flow Meter to Develop Velocity-Index Ratings and Evaluate the Effect of Flow Disturbances on these Ratings, Master’s Thesis: Department of Civil Engineering in the Graduate College of the University of Illinois at Urbana-Champaign, 2012.

    43-12  A. A. Girgidov, A. D. Girgidov and M. P. Fedorov, Use of dispersing springboards to reduce near-bottom velocity in a toe basin, Power Technology and Engineering (formerly Hydrotechnical Construction), Volume 46, Number 2 (2012), 113-115, DOI: 10.1007/s10749-012-0316-y.

    40-12  Jong Pil Park, Kyung Sik Choi, Ji Hwan Jeong, Gyung Min Choi, Ju Yeop Park, and Man Woong Kim, Experimental and numerical evaluation of debris transport augmentation by turbulence during the recirculation-cooling phase, Nuclear Engineering and Design 250 (2012) 520-537

    39-12  Hossein Basser, Abdollah Ardeshir, Hojat Karami, Numerical simulation of flow pattern around spur dikes series in rigid bed, 9th International Congress on Civil Engineering, May 8-10, 2012 Isfahan University of Technology (IUT), Isfahan, Iran

    38-12  Sathaporn Temeepattanapongsa, Unified Equations for Cutthroat Flumes Derived from a Three-Dimensional Hydraulic Model, (2012). Thesis: Utah State University, All Graduate Theses and Dissertations. Paper 1308. Available online at: http://digitalcommons.usu.edu/etd/1308

    36-12 Robert Feurich, Jacques Boubée, Nils Reidar B. Olsen, Improvement of fish passage in culverts using CFD, Ecological Engineering, Volume 47, October 2012, Pages 1–8.

    35-12 Yovanni A. Cataño-Lopera and Jorge D. Abad, Flow Structure around a Partially Buried Object in a Simulated River Bed, World Environmental And Water Resources Congress 2012, Albuquerque, New Mexico, United States, May 20-24, 2012.

    33-12  Fatemeh Rostami, Saeed Reza Sabbagh Yazdi, Md Azlin Md Said and Mahdi Shahrokhi, Numerical simulation of undular jumps on graveled bed using volume of fluid method, Water Science & Technology Vol 66 No 5 pp 909–917 © IWA Publishing 2012 doi:10.2166/wst.2012.213.

    30-12  Saman Abbasi and Amir Abbas Kamanbedast, Investigation of Effect of Changes in Dimension and Hydraulic of Stepped Spillways for Maximization Energy Dissipation, World Applied Sciences Journal 18 (2): 261-267, 2012, ISSN 1818-4952, © IDOSI Publications, 2012, DOI: 10.5829/idosi.wasj.2012.18.02.492

    24-12  Mario Oertel, Jan Mönkemöller and Andreas Schlenkhoff, Artificial stationary breaking surf waves in a physical and numerical model, Journal of Hydraulic Research, 50:3, 338-343, 2012.

    23-12  Mario Oertel, Cross-bar block ramps:Flow regimes – flow resistance – energy dissipation – stability, thesis, Bericht Nr. 20, 2012, © 2011/12 Dr. Mario Oertel, Hydraulic Engineering Section, Bergische University of Wuppertal. Duplication only with author’s permission.

    20-12  M. Oertel and A. Schlenkhoff, Crossbar Block Ramps: Flow Regimes, Energy Dissipation, Friction Factors, and Drag Forces, Journal of Hydraulic Engineering © ASCE, May 2012, pp. 440-448.

    19-12  Mohsen Maghrebi, Saeed Alizadeh, and Rahim Lotfi, Numerical Simulation of Flow Over Rectangular Broad Crested Weir, 1st International and 3rd National Conference on Dams and Hydropower in Iran, Tehran, Iran, February 8 – February 9, 2012

    18-12  Alireza Daneshkhah and Hamidreza Vosoughifar, Solution of Flow Field Equations to Investigate the Best Turbulent Model of Flow over a Standard Ogee Spillway, 1st International and 3rd National Conference on Dams and Hydropower in Iran, Tehran, Iran, February 8 – February 9, 2012

    03-12  Hamed Taghizadeh, Seyed Ali Akbar Salehi Neyshabour and Firouz Ghasemzadeh, Dynamic Pressure Fluctuations in Stepped Three-Side Spillway, Iranica Journal of Energy & Environment 3 (1): 95-104, 2012, ISSN 2079-2115

    02-12   Kim, Seojun, Yu, Kwonkyu, Yoon, Byungman, and Lim, Yoonsung, A numerical study on hydraulic characteristics in the ice Harbor-type fishway, KSCE Journal of Civil Engineering, 2012-02-01, Issn: 1226-7988, pp 265- 272, Volume: 16, Issue: 2, Doi: 10.1007/s12205-012-0010-5.

    105-11 Hatice Ozmen Cagatay and Selahattin Kocaman, Dam-break Flow in the Presence of Obstacle: Experiment and CFD Simulation, Engineering Applications of Computational Fluid Mechancis, Vol. 5, No. 4, pp. 541-552, 2011

    102-11 Sang Do An, Interflow Dynamics and Three-Dimensional Modeling of Turbid Density Currents in IMHA Reservoir, South Korea, thesis: Doctor of Philosophy, Department of Civil and Environmental Engineering at Colorado State University, 2011.

    101-11 Tsunami – A Growing Disaster, edited by Mohammad Mokhtari, ISBN 978-953-307-431-3, 232 pages, Publisher: InTech, Chapters published December 16, 2011 under CC BY 3.0 license, DOI: 10.5772/922. Available for download at Intech.

    98-11  Selahattin Kocaman and Hasan Guzel, Numerical and Experimental Investigation of Dam-Break Wave on a Single Building Situated Downstream, Epoka Conference Systems, 1st International Balkans Conference on Challenges of Civil Engineering, 19-21 May 2011, EPOKA University, Tirana, Albania.

    97-11   T. Endreny, L. Lautz, and D. I. Siegel, Hyporheic flow path response to hydraulic jumps at river steps: Flume and hydrodynamic models, WATER RESOURCES RESEARCH, VOL. 47, W02517, doi:10.1029/2009WR008631, 2011.

    96-11   Mahdi Shahrokhi, Fatemeh Rostami, Md Azlin Md Said and Syafalni, Numerical Simulation of Influence of Inlet Configuration on Flow Pattern in Primary Rectangular Sedimentation Tanks, World Applied Sciences Journal 15 (7): 1024-1031, 2011, ISSN 1818-4952, © IDOSI Publications, 2011. Full article available online at IODSI.

    94-11  Kathleen H. Frizell, Summary of Hydraulic Studies for Ladder and Flume Fishway Design- Nimbus Hatchery Fish Passage Project, Hydraulic Laboratory Report HL-2010-04, U.S. Department of the Interior Bureau of Reclamation Technical Service Center Hydraulic Investigations and Laboratory Services Group, December 2011

    88-11   Abdelaziz, S, Bui, MD, Rutschmann, P, Numerical Investigation of Flow and Sediment Transport around a Circular Bridge Pier, Proceedings of the 34th World Congress of the International Association for Hydro- Environment Research and Engineering: 33rd Hydrology and Water Resources Symposium and 10th Conference on Hydraulics in Water Engineering, ACT: Engineers Australia, 2011: 2624-2630.

    86-11  M. Heidarnejad, D. Halvai and M. Bina, The Proper Option for Discharge the Turbidity Current and Hydraulic Analysis of Dez Dam Reservoir, World Applied Sciences Journal 13 (9): 2052-2056, 2011, ISSN 1818-4952 © IDOSI Publications, 2011

    84-11  Martina Reichstetter and Hubert Chanson, Physical and Numerical Modelling of Negative Surges in Open Channels, School of Civil Engineering at the University of Queensland, Report CH84/11, ISBN No. 9781742720388, © Reichstetter and Chanson, 2011.

    83-11  Reda M. Abd El-Hady Rady, 2D-3D Modeling of Flow Over Sharp-Crested Weirs, Journal of Applied Sciences Research, 7(12): 2495-2505, ISSN 1819-544X, 2011.

    78-11  S. Abbasi, A. Kamanbedast and J. Ahadian, Numerical Investigation of Angle and Geometric of L-Shape Groin on the Flow and Erosion Regime at River Bends, World Applied Sciences Journal 15 (2): 279-284, 2011, ISSN 1818-4952 © IDOSI Publications, 2011.

    75-11  Mario Oertel and Daniel B. Bung, Initial stage of two-dimensional dam-break waves: laboratory versus VOF, Journal of Hydraulic Research, DOI: 10.1080/00221686.2011.639981, Available online: 08 Dec 2011.

    73-11  T.N. Aziz and A.A. Khan, Simulation of Vertical Plane Turbulent Jet in Shallow Water, Advances in Civil Engineering, vol. 2011, Article ID 292904, 10 pages, 2011. doi:10.1155/2011/292904.

    67-11   Chung R. Song, ASCE, Jinwon Kim, Ge Wang, and Alexander H.-D. Cheng, Reducing Erosion of Earthen Levees Using Engineered Flood Wall SurfaceJournal of Geotechnical and Geoenvironmental Engineering, Vol. 137, No. 10, October 2011, pp. 874-881, http://dx.doi.org/10.1061/(ASCE)GT.1943-5606.0000500.

    64-11  Mahdi Shahrokhi, Fatemeh Rostami, Md Azlin Md Said, Syafalni, The Effect of Number of Baffles on the Improvement Efficiency of Primary Sedimentation Tanks, Available online 11 November 2011, ISSN 0307-904X, 10.1016/j.apm.2011.11.001.

    62-11  Jana Hadler, Klaus Broekel, Low head hydropower – its design and economic potential, World Renewable Energy Congress 2011, Sweden, May 8-13, 2011.

    60-11 Md. Imtiaj Hassan and Nahidul Khan, Performance of a Quarter-Pitch Twisted Savonius Turbine, The International Conference and Utility Exhibition 2011, Pattaya City, Thailand, 28-30 September 2011.

    59-11   Erin K. Gleason, Ashraful Islam, Liaqat Khan, Darrne Brinker and Mike Miller, Spillway Analysis Techniques Using Traditional and 3-D Computational Fluid Dynamics Modeling, Dam Safety 2011, National Harbor, MD, September 25-29, 2011.

    58-11  William Rahmeyer, Steve Barfuss, and Bruce Savage, Composite Modeling of Hydraulic Structures, Dam Safety 2011, National Harbor, MD, September 25-29, 2011.

    57-11  B. Dasgupta, K. Das, D. Basu, and R. Green, Computational Methodology to Predict Rock Block Erosion in Plunge Pools, Dam Safety 2011, National Harbor, MD, September 25-29, 2011.

    56-11  Jeff Burnham, Modeling Dams with Computational Fluid Dynamics- Past Success and New Directions, Dam Safety 2011, National Harbor, MD, September 25-29, 2011.

    52-11  Madhi Shahrokhi, Fatemeh Rostami, Md Azlin Md Said, and Syafalni, The Computational Modeling of Baffle Configuration in the Primary Sedimentation Tanks, 2011 2nd International Conference on Environmental Science and Technology IPCBEE vol 6. (2011) IACSIT Press, Singapore.

    47-11  Stefan Haun, Nils Reidar B. Olsen and Robert Feurich, Numerical Modeling of Flow over Trapezoidal Broad-Crested Weir, Engineering Applications of Computational Fluid Mechanics Vol 5., No. 3, pp. 397-405, 2011.

    42-11  Anu Acharya, Experimental Study and Numerical Simulation of Flow and Sediment Transport around a Series of Spur Dikes, thesis: The University of Arizona Graduate College, Copyright © Anu Acharya 2011, July 2011.

    38-11  Mehdi Shahosseini, Amirabbas Kamanbedast and Roozbeh Aghamajidi, Investigation of Hydraulic Conditions around Bridge Piers and Determination of Shear Stress using Numerical Methods, World Environmental and Water Resources Congress 2011, © ASCE 2011.

    35-11  L. Toombes and H. Chanson, Numerical Limitations of Hydraulic Models, 34th IAHR World Congress, 33rd Hydrology & Water Resources Symposium, 10th Hydraulics Conference, Brisbane, Australia, 26 June – 1 July 2011.

    34-11  Mohammad Sarfaraz, and Jalal Attari, Numerical Simulation of Uniform Flow Region over a Steeply Sloping Stepped Spillway, 6th National Congress on Civil Engineering, Semnan University, Semnan, Iran, April 26-27, 2011.

    30-11  John Richardson and Pamela Waterman, Stemming the Flood, Mechanical Engineering, Vol. 133/No.7 July 2011

    29-11  G. Möller & R. Boes, D. Theiner & A. Fankhauser, G. De Cesare & A. Schleiss, Hybrid modeling of sediment management during drawdown of Räterichsboden reservoir, Dams and Reservoirs under Changing Challenges – Schleiss & Boes (Eds), © 2011 Taylor & Francis Group, London, ISBN 978-0-415-68267-1.

    24-11  Liaqat A. Khan, Computational Fluid Dynamics Modeling of Emergency Overflows through an Energy Dissipation Structure of a Water Treatment Plant, ASCE Conf. Proc. doi:10.1061/41173(414)155, World Environmental and Water Resources Congress 2011.

    23-11  Anu Acharya and Jennifer G. Duan, Three Dimensional Simulation of Flow Field around Series of Spur Dikes, ASCE Conf. Proc. doi:10.1061/41173(414)218, World Environmental and Water Resources Congress 2011.

    22-11  Mehdi Shahosseini, Amirabbas Kamanbedast, and Roozbeh Aghamajidi, Investigation of Hydraulic Conditions around Bridge Piers and Determination of Shear Stress Using Numerical Method, ASCE Conf. Proc. doi:10.1061/41173(414)435, World Environmental and Water Resources Congress 2011.

    20-11  Jong Pil Park, Ji Hwan Jeong, Won Tae Kim, Man Woong Kim and Ju Yeop Park, Debris transport evaluation during the blow-down phase of a LOCA using computational fluid dynamics, Nuclear Engineering and Design, June 2011, ISSN 0029-5493, DOI: 10.1016/j.nucengdes.2011.05.017.

    13-11 Ehab A. Meselhe, Myrtle Grove Delta Building Diversion Project, The Geological Society of America, South-Central Section – 45th Annual Meeting, New Orleans, Louisiana, March 2011.

    12-11  Bryan Heiner and Steven L. Barfuss, Parshall Flume and Discharge Corrections Wall Staff Gauge and Centerline Measurements, Journal of Irrigation and Drainage Engineering, posted ahead of print February 1, 2011, DOI:10.1061/(ASCE)IR.1943-4774.0000355, © 2011 by the American Society of Civil Engineers.

    06-11  T. Endreny, L. Lautz, and D. Siegel, Hyporheic flow path response to hydraulic jumps at river steps- Hydrostatic model simulations, Water Resources Research, Vol. 47, W02518, doi: 10.1029/2010WR010014, 2011, © 2011 by the American Geophysical Union, 0043-1397/11/2010WR010014

    03-11  Jinwon Kim, Chung R. Song, Ge Wang and Alexander H.-D. Cheng Reducing Erosion of Earthen Levees Using Engineered Flood Wall Surface, Journal of Geotechnical and Geoenvironmental Engineering, © ASCE, January 2011.

    02-11  F. Montagna, G. Bellotti and M. Di Risio, 3D numerical modeling of landslide-generated tsunamis around a conical island, Springer Link, Earth and Environmental Science, Natural Hazards, DOI: 10.1007/s11069-010-9689-0, Online First™, 7 January 2011.

    83-10   S. Abdelaziz, M.D. Bui and P. Rutschmann, Numerical simulation of scour development due to submerged horizontal jet, River Flow 2010, eds. Dittrich, Koll, Aberle & Geisenhainer, © 2010 Bundesanstalt für Wasserbau, ISBN 978-3-939230-00-7.

    79-10  Daniel J. Howes, Charles M. Burt, and Brett F. Sanders, Subcritical Contraction for Improved Open-Channel Flow Measurement Accuracy with an Upward-Looking ADVM, J. Irrig. Drain Eng. 2010.136:617-626.

    78-10  M. Kaheh, S. M. Kashefipour, and A. Dehghani, Comparison of k-ε and RNG k-ε Turbulent Models for Estimation of Velocity Profiles along the Hydraulic Jump, presented at the 6th International Symposium on Environmental Hydraulics, Athens, Greece, June 2010.

    75-10  Shahrokh Amiraslani, Jafar Fahimi, Hossein Mehdinezhad, The Numerical Investigation of Free Falling Jet’s Effect on the Scour of Plunge Pool, XVIII International Conference on Water Resources CMWR 2010 J. Carrera (Ed) CIMNE, Barcelona 2010

    74-10  M. Ho Ta Khanh, Truong Chi Hien, and Dinh Sy Quat, Study and construction of PK Weirs in Vietnam (2004 to 2011), 78th Annual Meeting of the International Commission on Large Dams,  VNCOLD, Hanoi, Vietnam, May 23-26, 2010.

    72-10  DKH Ho and KM Riddette, Application of computational fluid dynamics to evaluate hydraulic performance of spillways in Australia, © Institution of Engineers Australia, 2010, Australian Journal of Civil Engineering, Vol 6 No 1, 2010.

    71-10  Cecilia Lucino, Sergio Liscia y Gonzalo Duro, Vortex Detection in Pump Sumps by Means of CFD, XXIV Latin American Congress on Hydraulics, Punta Del Este, Uruguay, November 2010; Deteccion de Vortices en Darsenas de Bombeo Mediante Modelacion MatematicaAvailable in English and Spanish.

    64-10 Jose (Pepe) Vasquez, Assessing Sediment Movement by CFD Particle Tracking, 2nd Joint Federal Interagency Conference, Las Vegas, Nevada, June 27-July 1, 2010.

    63-10 Sung-Min Cho, Foundation Design of the Incheon Bridge, Geotechnical Engineering Journal of the SEAGS & AGSSEA Vol 41 No.4, ISSN0046-5828, December 2010.

    61-10  I. Meireles, F.A. Bombardelli and J. Matos, Experimental and Numerical Investigation of the Non-Aerated Skimming Flow on Stepped Spillways Over Embankment Dams, Presented at the 2010 IAHR European Congress, Edinburgh, UK, May 4-6, 2010.

    60-10  Mario Oertel, G. Heinz and A. Schlenkhoff, Physical and Numerical Modelling of Rough Ramps and Slides, Presented at the 2010 IAHR European Congress, Edinburgh, UK, May 4-6, 2010.

    59-10  Fatemeh Rostami, Mahdi Shahrokhi, Md Azlin Md Said, Rozi Abdullah and Syafalni, Numerical modeling on inlet aperture effects on flow pattern in primary settling tanks, Applied Mathematical Modelling, Copyright © 2010 Elsevier Inc., DOI: 10.1016/j.apm.2010.12.007, December 2010.

    56-10  G. B. Sahoo, F Bombardelli, D. Behrens and J.L. Largier, Estimation of Stratification and Mixing of a Closed River System Using FLOW-3D, American Geophysical Union, Fall Meeting 2010, abstract #H31G-1091

    50-10  Sung-Duk Kim, Ho-Jin Lee and Sang-Do An, Improvement of hydraulic stability for spillway using CFD model, International Journal of the Physical Sciences Vol. 5(6), pp. 774-780, June 2010. Available online at http://www.academicjournals.org/IJPS, ISSN 1992

    49-10  Md. Imtiaj Hassan, Tariq Iqbal, Nahidul Khan, Michael Hinchey, Vlastimil Masek, CFD Analysis of a Twisted Savonius Turbine, PKP Open Conference Systems, IEEE Newfoundland and Labrador Section, October 2010

    46-10  Hatice Ozmen-Cagatay and Selahattin Kocaman, Dam-break flows during initial stage using SWE and RANS approaches, Journal of Hydraulic Research, Vol 48, No. 5 (2010), pp. 603-611, doi: 10.108/00221686.2010.507342, © 2010 International Association for Hydro-Environment Engineering and Research.

    44-10  Marie-Hélène Briand, Catherine Tremblay, Yannick Bossé, Julian Gacek, Carola Alfaro, and Richard Blanchet, Ashlu Creek hydroelectric project- Design and optimization of hydraulic structures under construction, CDA 2010 Annual Conference, Congrès annuel 2010 de l’A CB, Niagra Falls, ON, Canada, 2010 Oct 2-7.

    43-10 Gordon McPhail, Justin Lacelle, Bert Smith, and Dave MacMillan, Upgrading of Boundary Dam Spillway, CDA 2010 Annual Conference, Congrès annuel 2010 de l’A CB, Niagra Falls, ON, Canada, 2010 Oct 2-7.

    40-10 Selahattin Kocamana; Galip Seckinb; Kutsi S. Erduran, 3D model for prediction of flow profiles around bridges, DOI: 10.1080/00221686.2010.507340, Journal of Hydraulic Research, Volume 48, Issue 4 August 2010, pages 521 – 525. Available online at: informaworld

    38-10  Kevin M. Sydor and Pamela J. Waterman, Engineering and Design: The Value of CFD Modeling in Designing a Hydro Plant, Hydro Review, Volume 29, Issue 6, September 2010 Available online at HydroWorld.com

    33-10  Fabián A. Bombardelli, Inês Meireles and Jorge Matos, Laboratory measurements and multi-block numerical simulations of the mean flow and turbulence, SpringerLink, Environmental Fluid Mechanics, Online First™, 26 August 2010

    30-10 Bijan Dargahi, Flow characteristics of bottom outlets with moving gates, IAHR, Journal of Hydraulic Research, Vol. 48, No. 4 (2010), pp. 476-482, doi: 10.1080/00221686.20101.507001, © 2010 International Association for Hydro-Environment Engineering and Research

    24-10 Shuang Ming Wang and Kevin Sydor, Power Intake Velocity Modeling Using FLOW-3D at Kelsey Generating Station, Canadian Dam Association Bulletin, Vol. 21. No. 2, Spring 2010, pp: 16-21

    20-10 Jungseok Ho, Todd Marti and Julie Coonrod, Flood debris filtering structure for urban storm water treatment, DOI: 10.1080/00221686.2010.481834, Journal of Hydraulic Research, Volume 48, Issue 3, pages 320 – 328, June 2010.

    16-10 J. Jacobsen and N. R. B. Olsen, Three-dimensional numerical modeling of the capacity for a complex spillway, Proceedings of the ICE – Water Management, Volume 163, Issue 6, pages 283 –288, ISSN: 1741-7589, E-ISSN: 1751-7729.

    13-10 J. Ho, J. Coonrod, L. J. Hanna, B. W. Mefford, Hydrodynamic modelling study of a fish exclusion system for a river diversion, River Research and Applications Volume 9999, mIssue 9999, Copyright © 2005 John Wiley & Sons, Ltd.

    12-10 Nils Rüther, Jens Jacobsen, Nils Reidar B. Olsen and Geir Vatne, Prediction of the three-dimensional flow field and bed shear stresses in a regulated river in mid-Norway, Hydrology Research Vol 41 No 2 pp 145–152 © IWA Publishing 2010, doi:10.2166/nh.2010.064.

    11-10 Xing Fang, Shoudong Jiang, and Shoeb R. Alam, Numerical Simulations of Efficiency of Curb-Opening Inlets, J. Hydr. Engrg. Volume 136, Issue 1, pp. 62-66 (January 2010).

    54-09    K.W. Frizell, J.P. Kubitschek, and R.F. Einhellig, Folsom Dam Joint Federal Project Existing Spillway Modeling – Discharge Capacity Studies, American River Division Central Valley Project Mid-Pacific Region, Hydraulic Laboratory Report HL-2009-02, US Department of the Interior, Bureau of Reclamation, Denver, Colorado, September 2009

    50-09  Mark Fabian, Variation in Hyporheic Exchange with Discharge and Slope in a Tropical Mountain Stream, thesis: State University of New York, College of Environmental Science & Forestry, 2009. Available online: http://gradworks.umi.com/14/82/1482174.html.

    48-09 Junwoo Choi, Kwang Oh Ko, and Sung Bum Yoon, 3D Numerical Simulation for Equivalent Resistance Coefficient for Flooded Built-Up Areas, Asian and Pacific Coasts 2009 (pp 245-251), Proceedings of the 5th International Conference on APAC 2009, Singapore, 13 – 16 October 2009

    47-09 Young-Il Kim, Chang-Jin Ahn, Chae-Young Lee, Byung-Uk Bae, Computational Fluid Dynamics for Optimal Design of Horizontal-Flow Baffled-Channel Powdered Activated Carbon Contactors, Mary Ann Liebert, Inc. publishers, Volume: 26 Issue 1: January 15, 2009.

    43-09 Charles R. Ortloff, Water Engineering in the Ancient World: Archaeological and Climate Perspectives on Societies of Ancient South America, Meso-America, the Middle East and South East Asia, Oxford University Press, ISBN13: 978-0-19-923909-2ISBN10: 0-19-923909-6, December 2009 Available at Oxford University Press (clicking on this link will take you to OUP’s website).

    40-09 Ge Wang, Chung R. Song, Jinwon Kim and Alexander, H.-D Cheng, Numerical Study of Erosion-proof of Loose Sand in an Overtopped Plunging Scour Process — FLOW-3D, The 2009 Joint ASCE-ASME-SES Conference on Mechanics and Materials, Blacksburg, Virginia, June 24-27, 2009

    39-09 Charles R. Ortloff, Water Engineering in the Ancient World: Archaeological and Climate Perspectives on Societies of Ancient South America, the Middle East, and South-East Asia(Hardcover), Oxford University Press, USA (October 15, 2009), ISBN-10: 0199239096; ISBN-13: 978-0199239092 Buy Water Engineering in the Ancient World on Amazon.com.

    38-09 David S. Brown, Don MacDonell, Kevin Sydor, and Nicolas Barnes, An Integrated Computational Fluid Dynamics and Fish Habitat Suitability Model for the Pointe Du Bois Generating Station, CDA 2009 Annual Conference, Congres annuel 2009 de l’A CB, Whistler, BC, Canada, 2009 Oct 3-8, pdf pages: 53-66

    37-09 Warren Gendzelevich, Andrew Baryla, Joe Groenveld, and Doug McNeil, Red River Floodway Expansion Project-Design and Construction of the Outlet Structure, CDA 2009 Annual Conference, Congres annuel 2009 de l’A CB, Whistler, BC, Canada, 2009 Oct 3-8, pdf pages: 13-26

    36-09 Jose A. Vasquez and Jose J. Roncal, Testing River2D and FLOW-3D for Sudden Dam-Break Flow Simulations, CDA 2009 Annual Conference, Congres annuel 2009 de l’A CB, Whistler, BC, Canada, 2009 Oct 3-8, pdf pages: 44-55

    33-09 Pamela J. Waterman, Modeling Commercial Aquaculture Systems Employing FLOW-3D, (clicking on this link will take you to Desktop Engineering’s website) Desktop Engineering, November 2009

    29-09 Bruce M. Savage, Michael C. Johnson, Brett Towler, Hydrodynamic Forces on a Spillway- Can we calculate them?, Dam Safety 2009, Hollywood, FL, USA, October 2009

    27-09 Charles “Chick” Sweeney, Keith Moen, and Daniel Kirschbaum, Hydraulic Design of Total Dissolved Gas Mitigation Measures for Boundary Dam, Waterpower XVI, © PennWell Corporation, Spokane, WA, USA, July 2009

    23-09 J.A. Vasquez and B.W. Walsh, CFD simulation of local scour in complex piers under tidal flow, 33rd IAHR Congress: Water Engineering for a Sustainable Environment, © 2009 by International Association of Hydraulic Engineering & Research (IAHR), ISBN: 978-94-90365-01-1

    15-09 Kaushik Das, Steve Green, Debashis Basu, Ron Janetzke, and John Stamatakos, Effect of Slide Deformation and Geometry on Waves Generated by Submarine Landslides- A Numerical Investigation, Copyright 2009, Offshore Technology Conference, Houston, Texas, USA, May 4-7, 2009

    5-09 Remi Robbe, Douglas Sparks, Calculation of the Rating Curves for the Matawin Dam’s Bottom Sluice Gates using FLOW-3D, Conference of the Société Hydrotechnique de France (SHF), 20-21 January 2009, Paris, France. (in French)

    4-09 Frederic Laugier, Gregory Guyot, Eric Valette, Benoit Blancher, Arnaud Oguic, Lily Lincker, Engineering Use of Hydrodynamic 3D Simulation to Assess Spillway Discharge Capacity, Conference of the Société Hydrotechnique de France (SHF), 20-21 January 2009, Paris, France. (in French)

    50-08   H. Avila and R.Pitt, The Calibration and use of CFD Models to Examine Scour from Stormwater Treatment Devices – Hydrodynamic Analysis, 11th International Conference on Urban Drainage, Edinburgh, Scotland, UK, 2008

    47-08    Greg Paxson, Brian Crookston, Bruce Savage, Blake Tullis, and Frederick Lux III, The Hydraulic Design Toolbox- Theory and Modeling for the Lake Townsend Spillway Replacement Project, Assoc. of State Dam Safety Officials (ASDSO), Indian Wells, CA, September 2008.

    46-08  Sh. Amirslani, M. Pirestani and A.A.S. Neyshabouri, The 3D numerical simulation of scour by free falling jet and compare geometric parameters of scour hole with DOT, River flow 2008-Altinakar, Kokipar, Gogus, Tayfur, Kumcu & Yildirim (eds) © 2008 Kubaba Congress Department and Travel Services ISBN 978-605-601360201

    44-08  Paul Guy Chanel, An Evaluation of Computational Fluid Dynamics for Spillway Modeling, thesis: Department of Civil Engineering, University of Manitoba, Copyright © 2008 by Paul Guy Chanel

    41-08 Jinwei Qiu, Gravel transport estimation and flow simulation over low-water stream crossings, thesis: Lamar University – Beaumont, 2008, 255 pages; AAT 3415945

    37-08 Dae-Geun Kim, Numerical analysis of free flow past a sluice gate, KSCE Journal of Civil Engineering, Volume 11, Number 2 / March, 2007, 127-132.

    36-08 Shuang Ming Wang and Kevin Sydor, Power Intake Velocity Modeling using FLOW-3D at Kelsey Generating Station, CDA 2008 Annual Conference, Congres annuel 2008 de l’ACB, Winnipeg, MB, Canada, September 27-October 2, 2008, du 27 septembre au 2 octobre 2008

    33-08 Daniel B. Bung, Arndt Hildebrandt, Mario Oertel, Andreas Schlenkhoff and Torsten Schlurmann, Bore Propagation Over a Submerged Horizontal Plate by Physical and Numerical Simulation, ICCE 2008, Hamburg, Germany

    32-08 Paul G. Chanel and John C. Doering, Assessment of Spillway Modeling Using Computational Fluid Dynamics, Canadian Journal of Civil Engineering, 35: 1481-1485 (2008), doi: 10.1139/L08-094 © NRC Canada

    31-08 M. Oertel & A. Schlenkhoff, Flood wave propagation and flooding of underground facilities, River Flow 2008, © 2008, International Conference on Fluvial Hydraulics, Izmir, Turkey, September, 2008

    18-08 Efrem Teklemariam, Bernie Shumilak, Don Murray, and Graham K. Holder, Combining Computational and Physical Modeling to Design the Keeyask Station, Hydro Review, © HCI Publications, July 2008

    15-08 Jorge D. Abad; Bruce L. Rhoads; İnci Güneralp; and Marcelo H. García, Flow Structure at Different Stages in a Meander-Bend with Bendway Weirs, Journal of Hydraulic Engineering © ASCE, August 2008

    11-08 Sreenivasa C. Chopakatla, Thomas C. Lippmann and John E. Richardson, Field Verification of a Computational Fluid Dynamics Model for Wave Transformation and Breaking in the Surf Zone, J. Wtrwy., Port, Coast., and Oc. Engrg., Volume 134, Issue 2, pp. 71-80 (March/April 2008) Abstract Only

    51-07   Richmond MC, TJ Carlson, JA Serkowski, CB Cook, JP Duncan, and WA Perkins, Characterizing the Fish Passage Environment at The Dalles Dam Spillway: 2001-2004, PNNL-16521, Pacific Northwest National Laboratory, Richland, WA, 2007. Available upon request

    46-07 Uplift and Crack Flow Resulting from High Velocity Discharges Over Open Offset Joints, Reclamation, Managing Water in the West, U.S. Department of the Interior, Bureau of Reclamation, Report DSO-07-07, December 2007

    45-07 Selahattin Kocaman, thesis: Department of Civil Engineering, Institute of Natural and Applied Sciences, University of Çukurova, Experimental and Theoretical Investigation of Dam Break Problem, 2007. In Turkish. Available on request.

    44-07   Saeed-reza Sabbagh-yazdi, Fatemeh Rostami, Habib Rezaei-manizani, and Nikos E. Mastorakis, Comparison of the Results of 2D and 3D Numerical Modeling of Flow over Spillway chutes with Vertical Curvatures, International Journal of Computers, Issue 4, Volume 1, 2007.

    43-07    Staša Vošnjak and Jure Mlacnik, Verification of a FLOW-3D mathematical model by a physical hydraulic model of a turbine intake structure, International Conference and exhibition Hydro 2007, 15- 17 October 2007, Granada, Spain. New approaches for a new era: proceedings. [S.l.]: Aqua-Media International Ltd., 2007, 7 str. [COBISS.SI-ID 4991329]

    42-07   Merlynn D. Bender, Joseph P. Kubitschek, Tracy B. Vermeyen, Temperature Modeling of Folsom Lake, Lake Natoma, and the Lower American River, Special Report, Sacramento County, California, April 2007

    37-07 Heather D. Smith, Flow and Sediment Dynamics Around Three-Dimensional Structures in Coastal Environments, thesis: The Ohio State Unviersity, 2007 (available upon request)

    34-07   P.G. Chanel and J.C. Doering, An Evaluation of Computational Fluid Dynamics for Spillway Modeling, 16th Australasian Fluid Mechanics Conference, Gold Coast, Australia, December 2007

    29-07   J. Groeneveld, C. Sweeney, C. Mannheim, C. Simonsen, S. Fry, K. Moen, Comparison of Intake Pressures in Physical and Numerical Models of the Cabinet Gorge Dam Tunnel, Waterpower XV, Copyright HCI Publications, July 2007

    25-07   Jungseok Ho, Hong Koo Yeo, Julie Coonrod, Won-Sik Ahn, Numerical Modeling Study for Flow Pattern Changes Induced by Single Groyne, IAHR Conference Proc., Harmonizing the Demands of Art and Nature in Hydraulics, IAHR, July 2007, Venice, Italy.

    24-07   Jungseok Ho, Julie Coonrod, Todd Marti, Storm Water Best Management Practice- Development of Debris Filtering Structure for Supercritical Flow, EWRI Conference Proc. of World Water and Environmental Resources Congress, ASCE, May 2007, Tampa, Florida.

    21-07 David S. Mueller, and Chad R. Wagner, Correcting Acoustic Doppler Current Profiler Discharge Measurements Biased by Sediment Transport, Journal of Hydraulic Engineering, Volume 133, Issue 12, pp. 1329-1336 (December 2007), Copyright © 2007, ASCE. All rights reserved.

    19-07   A. Richard Griffith, James H. Rutherford, A. Alavi, David D. Moore, J. Groeneveld, Stability Review of the Wanapum Spillway Using CFD Analysis, Canadian Dam Association Bulletin, Fall 2007

    06-07   John E. Richardson, CFD Saves the Alewife- Computer simulation helps the Alewife return to its Mt. Desert Island spawning grounds, Desktop Engineering, July 2007; Hatchery International, July/August 2007

    39-06    Dae Geun Kim and Hong Yeun Cho, Modeling the buoyant flow of heated water discharged from surface and submerged side outfalls in shallow and deep water with a cross flow, Environ Fluid Mech (2006) 6: 501. https://doi.org/10.1007/s10652-006-9006-3

    38-06   Cook, C., B. Dibrani, M. Richmond, M. Bleich, P. Titzler, T. Fu, Hydraulic Characteristics of the Lower Snake River during Periods of Juvenile Fall Chinook Salmon Migration, 2002-2006 Final Report, Project No. 200202700, 176 electronic pages, (BPA Report DOE/BP-00000652-29)

    37-06  Cook CB, MC Richmond, and JA Serkowski, The Dalles Dam, Columbia River: Spillway Improvement CFD Study, PNNL-14768, Pacific Northwest National Laboratory, Richland, WA, 2006. Available upon request

    31-06 John P. Raiford and Abdul A. Khan, Numerical Modeling of Internal Flow Structure in Submerged Hydraulic Jumps, ASCE Conf. Proc. 200, 49 (2006), DOI:10.1061/40856(200)49

    29-06    Michael C. Johnson and Bruce Savage, Physical and Numerical Comparison of Flow over Ogee Spillway in the Presence of Tailwater, Journal of Hydraulic Engineering © ASCE, December 2006

    28-06   Greg Paxson and Bruce Savage, Labyrinth Spillways- Comparison of Two Popular U.S.A. Design Methods and Consideration of Non-standard Approach Conditions and Geometries, International Junior Researcher and Engineer Workshop on Hydraulic Structures, Report CH61/06, Div. of Civil Eng., The University of Queensland, Brisbane, Australia-ISBN 1864998687

    22-06   Brent Mefford and Jim Higgs, Link River Falls Passage Investigation – Flow Velocity Simulation, Water Resources Research Laboratory, February 2006

    27-06  Jungseok Ho, Leslie Hanna, Brent Mefford, and Julie Coonrod, Numerical Modeling Study for Fish Screen at River Intake Channel, EWRI Conference Proc. of World Water and Environmental Resources Congress, ASCE, May 2006, Omaha, Nebraska.

    17-06  Woolgar, Robert and Eddy, Wilmore, Using Computational Fluid Dynamics to Address Fish Passage Concerns at the Grand Falls-Windsor Hydroelectric Development, Canadian Dam Association meeting, Quebec City, Canada October 2006

    14-06  Fuamba, M., Role and behavior of surge chamber in hydropower- Case of the Robert Bourassa hydroelectric power plant in Quebec, Canada, Dams and Reservoirs, Societies and Environment in the 21st Century- Berga et al (eds) @ 2006 Taylor & Francis Group, London, ISBN 0 415 40423 1

    13-06  D.K.H. Ho, B.W. Cooper, K.M. Riddette, S.M. Donohoo, Application of numerical modelling to spillways in Australia, Dams and Reservoirs, Societies and Environment in the 21st Century—Berga et al (eds) © 2006 Taylor & Francis Group, London, ISBN 0 415 40423 1

    4-06 James Dexter, William Faisst, Mike Duer and Jerry Flanagan, Computer Simulation Helps Prevent Nitrification of Storage Reservoir, Waterworld, March 2006, pp 18-24

    36-05   P. Coussot, N. Rousell, Jarny and H. Chanson, (2005), Continuous or Catastrophic Solid-Liquid Transition in Jammed Systems, Physics of Fluids, Vol. 17, No. 1, Article 011703, 4 pages (ISSN 0031-9171).

    35-05    Dae Geun Kim and Jae Hyun Park, Analysis of Flow Structure over Ogee-Spillway in Consideration of Scale and Roughness Effects by Using CFD Model,  KSCE Journal of Civil Engineering. Volume 9, Number 2, March 2005, pp 161 – 169.

    31-05 Frank James Dworak, Characterizing Turbulence Structure along Woody Vegetated Banks in Incised Channels: Implications for Stream Restoration, thesis: The University of Tennessee, Knoxville, December 2005 (available upon request)

    29-05 Gessler, Dan and Rasmussen, Bernie, Before the Flood, Desktop Engineering, October 2005

    25-05   Jorge D. Abad and Marcelo H. Garcia, Hydrodynamics in Kinoshita-generated meandering bends- Importance for river-planform evolution, 4th IAHR Symposium on River, Coastal and Estuarine Morphodynamics, October 4-7, 2005, Urbana, Illinois

    23-05 Kristiansen T., Baarholm R., Stansberg C.T., Rørtveit G.J. and Hansen E.W., Steep Wave Kinematics and Interaction with a Vertical Column, Presented at The Fifth International Symposium on Ocean Wave Measurement and Analysis (Waves 2005), Spain, July, 2005

    16-05 Dan Gessler, CFD Modeling of Spillway Performance, Proceedings of the 2005 World Water and Environmental Resources Congress (sponsored by Environmental and Water Resources Institute of the American Society of Civil Engineers), May 15-19, 2005, Anchorage, Alaska

    12-05 Charles Ortloff, The Water Supply and Distribution System of the Nabataean City of Petra (Jordan), 300 BC- AD 300, Cambridge Archaeological Journal 15:1, 93-109

    33-04    Jose Carlos C. Amorim, Cavalcanti Renata Rodrigues, and Marcelo G. Marques, A Numerical and Experimental Study of Hydraulic Jump Stilling Basin, Advances in Hydro-Science and Engineering, Volume VI, Presented at the International Conference on Hydro-Science and Engineering, 2004

    23-04   Jose F. Rodriguez, Fabian A. Bombardelli, Marcelo H. Garcia, Kelly Frothingham, Bruce L. Rhoads and Jorge D. Abad, High-Resolution Numerical Simulation of Flow Through a Highly Sinuous River Reach, Water Resources Management, 18:177-199, 2004.

    18-04   John Richardson and Douglas Dixon, Modeling the Hydraulics Zone of Influence of Connecticut Yankee Nuclear Plants Cooling Water Intake Structure, a chapter in The Connecticut River Ecological Study (1965-1973) Revisited: Ecology of the Lower Connecticut River 1973-2003, Paul M. Jacobson, Douglas A. Dixon, William C. Leggett, Barton C. Marcy, Jr., and Ronald R. Massengill, editors; Published by American Fisheries Society, Publication date: November 2004, ISBN 1-888569-66-2

    10-04   Bruce Savage, Kathleen Frizell, and Jimmy Crowder, Brains versus Brawn- The Changing World of Hydraulic Model Studies

    7-04   C. B. Cook and M. C. Richmond, Monitoring and Simulating 3-D Density Currents and the Confluence of the Snake and Clearwater Rivers, Proceedings of EWRI World

    24-03  David Ho, Karen Boyes, Shane Donohoo, and Brian Cooper, Numerical Flow Analysis for Spillways, 43rd ANCOLD Conference, Hobart, Tasmania, 24-29 October 2003

    15-03   Ho, Dr K H, Boyes, S M, Donohoo, S M, Investigation of Spillway Behaviour Under Increased Maximum Flood by Computational Fluid Dynamics Technique, Proc Conf 14th Australian Fluid Mechanics, Adelaide, Australia, December 2001, 577-580

    14-03   Ho, Dr K H, Donohoo, S M, Boyes, K M, Lock, C C, Numerical Analysis and the Real World- It Looks Pretty, but is It Right?, Proceedings of the NAFEMS World Congress, May 2003, Orlando, FL

    13-03 Brethour, J. M., Sediment Scour, Flow Science Technical Note (FSI-03-TN62)

    26-02   Sungyul Yoo, Kiwon Hong and Manha Hwang, A 3-dimensional numerical study of flow patterns around a multipurpose dam, 2002 Hydroinformatics Conference, Cardiff, Wales

    23-02   Christopher B. Cook, Marshall C. Richmond, John A. Serkowski, and Laurie L. Ebner, Free-Surface Computational Fluid Dynamics Modeling of a Spillway and Tailrace- Case Study of The Dalles Project, Hydrovision 2002, 29 July -†2 Aug, 2002 Portland, OR

    13-02   Efrem Teklemariam, Brian W. Korbaylo, Joe L. Groeneveld & David M. Fuchs, Computational Fluid Dynamics- Diverse Applications In Hydropower Project’s Design and Analysis, June 11-14, 2002, CWRA 55th Annual Conference, Winnipeg, Manitoba, CA

    12-02   Snorre Heimsund, Ernst Hansen, W Nemec, Computational 3-D Fluid Dynamics Model for Sediment Transport, Erosion, and Deposition by Turbidity Currents, 16th International Sedimentological Congress Abstract Volume (2002) XX-XX

    9-02   D. T. Souders & C. W. Hirt, Modeling Roughness Effects in Open Channel Flows, Flow Science Technical Note (FSI-02-TN60), May 2002

    47-01    Fabián A. Bombardelli and Marcelo H. García, Three-dimensional Hydrodynamic Modeling of Density Currents in the Chicago River, Illinois, CIVIL ENGINEERING SERIES, UILU-ENG-01-2001 Hydraulic Engineering Series No. # 68, ISSN: 0442-1744, 2001

    44-01   Christopher B. Cook and Marshall C. Richmond, Simulation of Tailrace Hydrodynamics Using Computational Fluid Dynamics Models, Report Number: PNNL-13467, May 2001

    40-01 Joe L. Groeneveld, Kevin M. Sydor and David M. Fuchs (Acres Manitoba Ltd., Winnipeg, Manitoba, Canada) and Efrem Teklemariam and Brian W. Korbaylo (Manitoba Hydro, Winnipeg, Manitoba, Canada), Optimization of Hydraulic Design Using Computational Fluid Dynamics, Waterpower XII, July 9-11, 2001, Salt Lake City, Utah

    39-01   Savage, B.M and Johnson, M.C., Flow over Ogee Spillway- Physical and Numerical Model Case Study, Journal of Hydraulic Engineering, ASCE, August 2001, pp. 640-649

    38-01   Newell, Carter, Sustainable Mussel Culture- A Millenial Perspective, Bulletin of the Aquaculture Association of Canada, August 2001, pp 15-21

    36-01   Diane L. Foster, Ohio State University, Numerical Simulations of Sediment Transport and Scour Around Mines, paper presented to the Office of Naval Research, Mine Burial Prediction Program, 2001

    35-01 Heather D. Smith, Diane L. Foster, Ohio State University, The Modeling of Flow Around a Cylinder and Scour Hole, Poster prepared for the Office of Naval Research, Mine Burial Prediction Program, 2002

    28-01   Brethour, J.M., Transient 3D Model for Lifting, Transporting, and Depositing Solid Material, Proc. 3rd Intrn. Environmental Hydraulics, Dec. 5-8, 2001, Tempe, AZ

    25-01  Yuichi Kitamura, Takahiro Kato, & Petek Kitamura, Mathematical Modeling for Fish Adaptive Behavior in a Current, Proceedings of the 2001International Symposium of Environmental Hydraulics, Chigaski R&D Center

    22-01 C. R. Ortloff, D. P. Crouch, The Urban Water Supply and Distribution System of the Ionian City of Ephesos in the Roman Imperial Period, CTC/United Defense Journal of Archeological Science (2001), pp 843-860

    13-01 I. Lavedrine, and Darren Woolf, ARUP Research and Development, Application of CFD Modelling to Hydraulic Structures, CCWI 2001, Leicaster United Kingdom, 3-5 September 2001, De Montfort University

    4-01 Rodriguez, Garcia, Bombardelli, Guzman, Rhoads, and Herricks, Naturalization of Urban Streams Using In-Channel Structures, Joint Conference on Water Resources Engineering and Water Resources Planning and Management, ASCE, July 30-August 2, 2000, Minneapolis, Minnesota

    27-00    Tony L. Wahl, John A. Replogle, Brain T. Wahlin, and James A. Higgs, New Developments in Design and Application of Long-Throated Flumes, 2000 Joint Conference on Water Resources Engineering and Water Resources Planning & Management, Minneapolis, Minnesota, July 30-August 2, 2000.

    5-00   John E. Richardson and Karel Pryl, Computer Simulation Helps Prague Modernize and Expand Sewer System, Water Engineering and Management, June, 2000, pp. 10-13; and in Municipal World, June, 2000, pp. 19-20,30

    3-00 Efrem Teklemariam and John L. Groeneveld, Solving Problems in Design and Dam Safety with Computational Fluid Dynamics, Hydro Review, May, 2000, pp.48-52

    1-00 Scott F. Bradford, Numerical Simulation of Surf Zone Dynamics, Journal of Waterway, Port, Coastal and Ocean Engineering, January/February, 2000, pp.1-13

    9-99 John E. Richardson and Karel Pryl, Computational Fluid Dynamics, CE News, October, 1999, pp. 74-76

    4-99 J. Groeneveld, Computer Simulation Leads to Faster, Cheaper Options, Water Engineering & Management magazine, pp.14-17, June 1999

    16-98 C. R. Ortloff, Hydraulic Analysis of a Self-Cleaning Drainage Outlet at the Hellenistic City of Priene, Journal Archaeological Science, 25, 1211-1220, Article No. as980292, 1998

    13-98 J. F. Echols, M.A. Pratt, K. A. Williams, Using CFD to Model Flow in Large Circulating Water Systems, Proc. PowerGen International, Orlando, FL, Dec. 9-11, 1998.

    12-98 K. A. Williams, I. A. Diaz-Tous, P. Ulovg, Reduction in Pumping Power Requirements of the Circulation Water (CW) System at TU Electric’s Martin Lake Plant Using Computation Fluid Dynamics (CFD), ASME Mechanical Engineering Magazine, Jan. 1999

    8-98 D. Hrabak, K. Pryl, J. Richardson, Calibration of Flowmeters using FLOW-3D Software, Hydroinform, a.s., Prague, CTU Prague, Flow Science Inc, USA, proceedings from the 3rd International Novatech Conference, Lyon, France, May 4-6, 1998

    16-96 E. J. Kent and J.E. Richardson, Three-Dimensional Hydraulic Analysis for Calculation of Scour at Bridge Piers with Fender Systems, Earth Tech, Concord, NK and Flow Science Inc, Los Alamos, NM report, December 1996

    12-96 J. E. Richardson, Control of Hydraulic Jump by Abrupt Drop, XXVII IAHR Congress, Water for a Changing Global Community, San Francisco, August 10, 1997

    6-96 Y. Miyamoto, A Three-Dimensional Analysis around the Open Area of a Tsunami Breakwater, technical report, SEA Corporation, Tokyo, Japan, to be presented at the HYDROINFORMATICS 96 Conference, Zurich, Switzerland, Sept. 11-13, 1996

    4-95 J. E. Richardson, V. G. Panchang and E. Kent, Three-Dimensional Numerical Simulation of Flow Around Bridge Sub-structures, presented at the Hydraulics ’95 ASCE Conference, San Antonio, TX, Aug. 1995

    3-95 Y. Miyamoto and K. Ishino, Three Dimensional Flow Analysis in Open Channel, presented at the IAHR Conference, HYDRA 2000, Vol. 1, Thomas Telford, London, Sept. 1995

    16-94 M. S. Gosselin and D. M. Sheppard, Time Rate of Local Scour, proceedings of ASCE Conf. on Water Resources Engineering, San Antonio, TX, August 1994

    8-94 C. W. Hirt, Weir Discharges and Counter Currents, Flow Science report, FSI-94-00-3, to be presented at the Hydroinformatics Conference, IHE Delft, The Netherlands, Sept. 1994

    7-94 C. W. Hirt and K. A.Williams, FLOW-3D Predictions for Free Discharge and Submerged Parshall Flumes, Flow Science Technical Note #40, August 1994 (FSI-94-TN40)

    11-93 K. Ishino, H. Otani, R. Okada and Y. Nakagawa, The Flow Structure Around a Cylindrical Pier for the Flow of Transcritical Reynolds Number, Taisei Corp., Honshu Shikoku Bridge Authority, Akashi Kaikyo Ohashi Substructure Construction, Proc. XXV, Congress Intern. Assoc. Hydraulic Res., V, 417-424 (1993) Tokyo, Japan

    6-87 J.M. Sicilian, FLOW-3D Model for Flow in a Water Turbine Passage, Flow Science report, July 1987 (FSI-87-36-1)

    FLOW-3D/MP Features List

    FLOW-3D/MP Features

    FLOW-3D/MP v6.1 은 FLOW-3D v11.1 솔버에 기초하여 물리 모델, 특징 및 그래픽 사용자 인터페이스가 동일합니다. FLOW-3D v11.1의 새로운 기능은 아래 파란색으로 표시되어 있으며 FLOW-3D/MP v6.1 에서 사용할 수 있습니다. 새로운 개발 기능에 대한 자세한 설명은 FLOW-3D v11.1에서 새로운 기능을 참조하십시오.

    Meshing & Geometry

    • Structured finite difference/control volume meshes for fluid and thermal solutions
    • Finite element meshes in Cartesian and cylindrical coordinates for structural analysis
    • Multi-Block gridding with nested, linked, partially overlapping and conforming mesh blocks
    • Fractional areas/volumes (FAVOR™) for efficient & accurate geometry definition
    • Mesh quality checking
    • Basic Solids Modeler
    • Import CAD data
    • Import/export finite element meshes via Exodus-II file format
    • Grid & geometry independence
    • Cartesian or cylindrical coordinates
    Flow Type Options
    • Internal, external & free-surface flows
    • 3D, 2D & 1D problems
    • Transient flows
    • Inviscid, viscous laminar & turbulent flows
    • Hybrid shallow water/3D flows
    • Non-inertial reference frame motion
    • Multiple scalar species
    • Two-phase flows
    • Heat transfer with phase change
    • Saturated & unsaturated porous media
    Physical Modeling Options
    • Fluid structure interaction
    • Thermally-induced stresses
    • Plastic deformation of solids
    • Granular flow
    • Moisture drying
    • Solid solute dissolution
    • Sediment transport and scour
    • Cavitation (potential, passive tracking, active tracking)
    • Phase change (liquid-vapor, liquid-solid)
    • Surface tension
    • Thermocapillary effects
    • Wall adhesion
    • Wall roughness
    • Vapor & gas bubbles
    • Solidification & melting
    • Mass/momentum/energy sources
    • Shear, density & temperature-dependent viscosity
    • Thixotropic viscosity
    • Visco-elastic-plastic fluids
    • Elastic membranes & walls
    • Evaporation residue
    • Electro-mechanical effects
    • Dielectric phenomena
    • Electro-osmosis
    • Electrostatic particles
    • Joule heating
    • Air entrainment
    • Molecular & turbulent diffusion
    • Temperature-dependent material properties
    • Spray cooling
    Flow Definition Options
    • General boundary conditions
      • Symmetry
      • Rigid and flexible walls
      • Continuative
      • Periodic
      • Specified pressure
      • Specified velocity
      • Outflow
      • Grid overlay
      • Hydrostatic pressure
      • Volume flow rate
      • Non-linear periodic and solitary surface waves
      • Rating curve and natural hydraulics
      • Wave absorbing layer
    • Restart from previous simulation
    • Continuation of a simulation
    • Overlay boundary conditions
    • Change mesh and modeling options
    • Change model parameters
    Thermal Modeling Options
    • Natural convection
    • Forced convection
    • Conduction in fluid & solid
    • Fluid-solid heat transfer
    • Distributed energy sources/sinks in fluids and solids
    • Radiation
    • Viscous heating
    • Orthotropic thermal conductivity
    • Thermally-induced stresses
    Turbulence Models
    • RNG model
    • Two-equation k-epsilon model
    • Two-equation k-omega model
    • Large eddy simulation
    Metal Casting Models
    • Thermal stress & deformations
    • Iron solidification
    • Sand core blowing
    • Sand core drying
    • Permeable molds
    • Solidification & melting
    • Solidification shrinkage with interdendritic feeding
    • Micro & macro porosity
    • Binary alloy segregation
    • Thermal die cycling
    • Surface oxide defects
    • Cavitation potential
    • Lost-foam casting
    • Semi-solid material
    • Core gas generation
    • Back pressure & vents
    • Shot sleeves
    • PQ2 diagram
    • Squeeze pins
    • Filters
    • Air entrainment
    • Temperature-dependent material properties
    • Cooling channels
    • Fluid/wall contact time
    Numerical Modeling Options
    • TruVOF Volume-of-Fluid (VOF) method for fluid interfaces
    • First and second order advection
    • Sharp and diffuse interface tracking
    • Implicit & explicit numerical methods
    • GMRES, point and line relaxation pressure solvers
    • User-defined variables, subroutines & output
    • Utilities for runtime interaction during execution
    Fluid Modeling Options
    • One incompressible fluid – confined or with free surfaces
    • Two incompressible fluids – miscible or with sharp interfaces
    • Compressible fluid – subsonic, transonic, supersonic
    • Stratified fluid
    • Acoustic phenomena
    • Mass particles with variable density or diameter
    Shallow Flow Models
    • General topography
    • Raster data interface
    • Subcomponent-specific surface roughness
    • Wind shear
    • Ground roughness effects
    • Laminar & turbulent flow
    • Sediment transport and scour
    • Surface tension
    • Heat transfer
    • Wetting & drying
    Advanced Physical Models
    • General Moving Object model with 6 DOF–prescribed and fully-coupled motion
    • Rotating/spinning objects
    • Collision model
    • Tethered moving objects (springs, ropes, mooring lines)
    • Flexing membranes and walls
    • Porosity
    • Finite element based elastic-plastic deformation
    • Finite element based thermal stress evolution due to thermal changes in a solidifying fluid
    • Combusting solid components
    Chemistry Models
    • Stiff equation solver for chemical rate equations
    • Stationary or advected species
    Porous Media Models
    • Saturated and unsaturated flow
    • Variable porosity
    • Directional porosity
    • General flow losses (linear & quadratic)
    • Capillary pressure
    • Heat transfer in porous media
    • Van Genunchten model for unsaturated flow
    Discrete Particle Models
    • Massless marker particles
    • Mass particles of variable size/mass
    • Linear & quadratic fluid-dynamic drag
    • Monte-Carlo diffusion
    • Particle-Fluid momentum coupling
    • Coefficient of restitution or sticky particles
    • Point or volumetric particle sources
    • Charged particles
    • Probe particles
    Two-Phase & Two-Component Models
    • Liquid/liquid & gas/liquid interfaces
    • Variable density mixtures
    • Compressible fluid with a dispersed incompressible component
    • Drift flux
    • Two-component, vapor/non-condensable gases
    • Phase transformations for gas-liquid & liquid-solid
    • Adiabatic bubbles
    • Bubbles with phase change
    • Continuum fluid with discrete particles
    • Scalar transport
    • Homogeneous bubbles
    • Super-cooling
    Coupling with Other Programs
    • Geometry input from Stereolithography (STL) files – binary or ASCII
    • Direct interfaces with EnSight®, FieldView® & Tecplot® visualization software
    • Finite element solution import/export via Exodus-II file format
    • PLOT3D output
    • Neutral file output
    • Extensive customization possibilities
    • Solid Properties Materials Database
    Data Processing Options
    • State-of-the-art post-processing tool, FlowSight™
    • Batch post-processing
    • Report generation
    • Automatic or custom results analysis
    • High-quality OpenGL-based graphics
    • Color or B/W vector, contour, 3D surface & particle plots
    • Moving and stationary probes
    • Measurement baffles
    • Arbitrary sampling volumes
    • Force & moment output
    • Animation output
    • PostScript, JPEG & Bitmap output
    • Streamlines
    • Flow tracers
    User Conveniences
    • Active simulation control (based on measurement of probes)
    • Mesh generators
    • Mesh quality checking
    • Tabular time-dependent input using external files
    • Automatic time-step control for accuracy & stability
    • Automatic convergence control
    • Mentor help to optimize efficiency
    • Change simulation parameters while solver runs
    • Launch and manage multiple simulations
    • Automatic simulation termination based on user-defined criteria
    • Run simulation on remote servers using remote solving
    Multi-Processor Computing

    FLOW-3D Features

    The features in blue are newly-released in FLOW-3D v12.0.

    Meshing & Geometry

    • Structured finite difference/control volume meshes for fluid and thermal solutions
    • Finite element meshes in Cartesian and cylindrical coordinates for structural analysis
    • Multi-Block gridding with nested, linked, partially overlapping and conforming mesh blocks
    • Conforming meshes extended to arbitrary shapes
    • Fractional areas/volumes (FAVOR™) for efficient & accurate geometry definition
    • Closing gaps in geometry
    • Mesh quality checking
    • Basic Solids Modeler
    • Import CAD data
    • Import/export finite element meshes via Exodus-II file format
    • Grid & geometry independence
    • Cartesian or cylindrical coordinates

    Flow Type Options

    • Internal, external & free-surface flows
    • 3D, 2D & 1D problems
    • Transient flows
    • Inviscid, viscous laminar & turbulent flows
    • Hybrid shallow water/3D flows
    • Non-inertial reference frame motion
    • Multiple scalar species
    • Two-phase flows
    • Heat transfer with phase change
    • Saturated & unsaturated porous media

    Physical Modeling Options

    • Fluid structure interaction
    • Thermally-induced stresses
    • Plastic deformation of solids
    • Granular flow
    • Moisture drying
    • Solid solute dissolution
    • Sediment transport and scour
    • Sludge settling
    • Cavitation (potential, passive tracking, active tracking)
    • Phase change (liquid-vapor, liquid-solid)
    • Surface tension
    • Thermocapillary effects
    • Wall adhesion
    • Wall roughness
    • Vapor & gas bubbles
    • Solidification & melting
    • Mass/momentum/energy sources
    • Shear, density & temperature-dependent viscosity
    • Thixotropic viscosity
    • Visco-elastic-plastic fluids
    • Elastic membranes & walls
    • Evaporation residue
    • Electro-mechanical effects
    • Dielectric phenomena
    • Electro-osmosis
    • Electrostatic particles
    • Joule heating
    • Air entrainment
    • Molecular & turbulent diffusion
    • Temperature-dependent material properties
    • Spray cooling

    Flow Definition Options

    • General boundary conditions
      • Symmetry
      • Rigid and flexible walls
      • Continuative
      • Periodic
      • Specified pressure
      • Specified velocity
      • Outflow
      • Outflow pressure
      • Outflow boundaries with wave absorbing layers
      • Grid overlay
      • Hydrostatic pressure
      • Volume flow rate
      • Non-linear periodic and solitary surface waves
      • Rating curve and natural hydraulics
      • Wave absorbing layer
    • Restart from previous simulation
    • Continuation of a simulation
    • Overlay boundary conditions
    • Change mesh and modeling options
    • Change model parameters

    Thermal Modeling Options

    • Natural convection
    • Forced convection
    • Conduction in fluid & solid
    • Fluid-solid heat transfer
    • Distributed energy sources/sinks in fluids and solids
    • Radiation
    • Viscous heating
    • Orthotropic thermal conductivity
    • Thermally-induced stresses

    Numerical Modeling Options

    • TruVOF Volume-of-Fluid (VOF) method for fluid interfaces
    • Steady state accelerator for free-surface flows
    • First and second order advection
    • Sharp and diffuse interface tracking
    • Implicit & explicit numerical methods
    • Immersed boundary method
    • GMRES, point and line relaxation pressure solvers
    • User-defined variables, subroutines & output
    • Utilities for runtime interaction during execution

    Fluid Modeling Options

    • One incompressible fluid – confined or with free surfaces
    • Two incompressible fluids – miscible or with sharp interfaces
    • Compressible fluid – subsonic, transonic, supersonic
    • Stratified fluid
    • Acoustic phenomena
    • Mass particles with variable density or diameter

    Shallow Flow Models

    • General topography
    • Raster data interface
    • Subcomponent-specific surface roughness
    • Wind shear
    • Ground roughness effects
    • Manning’s roughness
    • Laminar & turbulent flow
    • Sediment transport and scour
    • Surface tension
    • Heat transfer
    • Wetting & drying

    Turbulence Models

    • RNG model
    • Two-equation k-epsilon model
    • Two-equation k-omega model
    • Large eddy simulation

    Advanced Physical Models

    • General Moving Object model with 6 DOF–prescribed and fully-coupled motion
    • Rotating/spinning objects
    • Collision model
    • Tethered moving objects (springs, ropes, breaking mooring lines)
    • Flexing membranes and walls
    • Porosity
    • Finite element based elastic-plastic deformation
    • Finite element based thermal stress evolution due to thermal changes in a solidifying fluid
    • Combusting solid components

    Chemistry Models

    • Stiff equation solver for chemical rate equations
    • Stationary or advected species

    Porous Media Models

    • Saturated and unsaturated flow
    • Variable porosity
    • Directional porosity
    • General flow losses (linear & quadratic)
    • Capillary pressure
    • Heat transfer in porous media
    • Van Genunchten model for unsaturated flow

    Discrete Particle Models

    • Massless marker particles
    • Multi-species material particles of variable size and mass
    • Solid, fluid, gas particles
    • Void particles tracking collapsed void regions
    • Non-linear fluid-dynamic drag
    • Added mass effects
    • Monte-Carlo diffusion
    • Particle-fluid momentum coupling
    • Coefficient of restitution or sticky particles
    • Point or volumetric particle sources
    • Initial particle blocks
    • Heat transfer with fluid
    • Evaporation and condensation
    • Solidification and melting
    • Coulomb and dielectric forces
    • Probe particles

    Two-Phase & Two-Component Models

    • Liquid/liquid & gas/liquid interfaces
    • Variable density mixtures
    • Compressible fluid with a dispersed incompressible component
    • Drift flux with dynamic droplet size
    • Two-component, vapor/non-condensable gases
    • Phase transformations for gas-liquid & liquid-solid
    • Adiabatic bubbles
    • Bubbles with phase change
    • Continuum fluid with discrete particles
    • Scalar transport
    • Homogeneous bubbles
    • Super-cooling
    • Two-field temperature

    Coupling with Other Programs

    • Geometry input from Stereolithography (STL) files – binary or ASCII
    • Direct interfaces with EnSight®, FieldView® & Tecplot® visualization software
    • Finite element solution import/export via Exodus-II file format
    • PLOT3D output
    • Neutral file output
    • Extensive customization possibilities
    • Solid Properties Materials Database

    Data Processing Options

    • State-of-the-art post-processing tool, FlowSight™
    • Batch post-processing
    • Report generation
    • Automatic or custom results analysis
    • High-quality OpenGL-based graphics
    • Color or B/W vector, contour, 3D surface & particle plots
    • Moving and stationary probes
    • Visualization of non-inertial reference frame motion
    • Measurement baffles
    • Arbitrary sampling volumes
    • Force & moment output
    • Animation output
    • PostScript, JPEG & Bitmap output
    • Streamlines
    • Flow tracers

    User Conveniences

    • Active simulation control (based on measurement of probes)
    • Mesh generators
    • Mesh quality checking
    • Tabular time-dependent input using external files
    • Automatic time-step control for accuracy & stability
    • Automatic convergence control
    • Mentor help to optimize efficiency
    • Units on all variables
    • Custom units
    • Component transformations
    • Moving particle sources
    • Change simulation parameters while solver runs
    • Launch and manage multiple simulations
    • Automatic simulation termination based on user-defined criteria
    • Run simulation on remote servers using remote solving
    • Copy boundary conditions to other mesh blocks

    Multi-Processor Computing

    • Shared memory computers
    • Distributed memory clusters

    FlowSight

    • Particle visualization
    • Velocity vector fields
    • Streamlines & pathlines
    • Iso-surfaces
    • 2D, 3D and arbitrary clips
    • Volume render
    • Probe data
    • History data
    • Vortex cores
    • Link multiple results
    • Multiple data views
    • Non-inertial reference frame
    • Spline clip