Validity evaluation of popular liquid-vapor phase change models for cryogenic self-pressurization process

극저온 자체 가압 공정을 위한 인기 있는 액체-증기 상 변화 모델의 타당성 평가

액체-증기 상 변화 모델은 밀폐된 용기의 자체 가압 프로세스 시뮬레이션에 매우 큰 영향을 미칩니다. Hertz-Knudsen 관계, 에너지 점프 모델 및 그 파생물과 같은 널리 사용되는 액체-증기 상 변화 모델은 실온 유체를 기반으로 개발되었습니다. 액체-증기 전이를 통한 극저온 시뮬레이션에 널리 적용되었지만 각 모델의 성능은 극저온 조건에서 명시적으로 조사 및 비교되지 않았습니다. 본 연구에서는 171가지 일반적인 액체-증기 상 변화 모델을 통합한 통합 다상 솔버가 제안되었으며, 이를 통해 이러한 모델을 실험 데이터와 직접 비교할 수 있습니다. 증발 및 응축 모델의 예측 정확도와 계산 속도를 평가하기 위해 총 <>개의 자체 가압 시뮬레이션이 수행되었습니다. 압력 예측은 최적화 전략이 서로 다른 모델 계수에 크게 의존하는 것으로 나타났습니다. 에너지 점프 모델은 극저온 자체 가압 시뮬레이션에 적합하지 않은 것으로 나타났습니다. 평균 편차와 CPU 소비량에 따르면 Lee 모델과 Tanasawa 모델은 다른 모델보다 안정적이고 효율적인 것으로 입증되었습니다.

Elsevier

International Journal of Heat and Mass Transfer

Volume 181, December 2021, 121879

International Journal of Heat and Mass Transfer

Validity evaluation of popular liquid-vapor phase change models for cryogenic self-pressurization process

Author links open overlay panelZhongqi Zuo, Jingyi Wu, Yonghua HuangShow moreAdd to MendeleyShareCite

https://doi.org/10.1016/j.ijheatmasstransfer.2021.121879Get rights and content

Abstract

Liquid-vapor phase change models vitally influence the simulation of self-pressurization processes in closed containers. Popular liquid-vapor phase change models, such as the Hertz-Knudsen relation, energy jump model, and their derivations were developed based on room-temperature fluids. Although they had widely been applied in cryogenic simulations with liquid-vapor transitions, the performance of each model was not explicitly investigated and compared yet under cryogenic conditions. A unified multi-phase solver incorporating four typical liquid-vapor phase change models has been proposed in the present study, which enables direct comparison among those models against experimental data. A total number of 171 self-pressurization simulations were conducted to evaluate the evaporation and condensation models’ prediction accuracy and calculation speed. It was found that the pressure prediction highly depended on the model coefficients, whose optimization strategies differed from each other. The energy jump model was found inadequate for cryogenic self-pressurization simulations. According to the average deviation and CPU consumption, the Lee model and the Tanasawa model were proven to be more stable and more efficient than the others.

Introduction

The liquid-vapor phase change of cryogenic fluids is widely involved in industrial applications, such as the hydrogen transport vehicles [1], shipborne liquid natural gas (LNG) containers [2] and on-orbit cryogenic propellant tanks [3]. These applications require cryogenic fluids to be stored for weeks to months. Although high-performance insulation measures are adopted, heat inevitably enters the tank via radiation and conduction. The self-pressurization in the tank induced by the heat leakage eventually causes the venting loss of the cryogenic fluids and threatens the safety of the craft in long-term missions. To reduce the boil-off loss and extend the cryogenic storage duration, a more comprehensive understanding of the self-pressurization mechanism is needed.

Due to the difficulties and limitations in implementing cryogenic experiments, numerical modeling is a convenient and powerful way to study the self-pressurization process of cryogenic fluids. However, how the phase change models influence the mass and heat transfer under cryogenic conditions is still unsettled [4]. As concluded by Persad and Ward [5], a seemingly slight variation in the liquid-vapor phase change models can lead to erroneous predictions.

Among the liquid-vapor phase change models, the kinetic theory gas (KTG) based models and the energy jump model are the most popular ones used in recent self-pressurization simulations [6]. The KTG based models, also known as the Hertz-Knudsen relation models, were developed on the concept of the Maxwell-Boltzmann distribution of the gas molecular [7]. The Hertz-Knudsen relation has evolved to several models, including the Schrage model [8], the Tanasawa model [9], the Lee model [10] and the statistical rate theory (SRT) [11], which will be described in Section 2.2. Since the Schrage model and the Lee model are embedded and configured as the default ones in the commercial CFD solvers Flow-3D® and Ansys Fluent® respectively, they have been widely used in self-pressurization simulations for liquid nitrogen [12], [13] and liquid hydrogen [14], [15]. The major drawback of the KTG models lies in the difficulty of selecting model coefficients, which were reported in a considerably wide range spanning three magnitudes even for the same working fluid [16], [17], [18], [19], [20], [21]. Studies showed that the liquid level, pressure and mass transfer rate are directly influenced by the model coefficients [16], [22], [23], [24], [25]. Wrong coefficients will lead to deviation or even divergence of the results. The energy jump model is also known as the thermal limitation model. It assumes that the evaporation and condensation at the liquid-vapor interface are induced only by heat conduction. The model is widely adopted in lumped node simulations due to its simplicity [6], [26], [27]. To improve the accuracy of mass flux prediction, the energy jump model was modified by including the convection heat transfer [28], [29]. However, the convection correlations are empirical and developed mainly for room-temperature fluids. Whether the correlation itself can be precisely applied in cryogenic simulations still needs further investigation.

Fig. 1 summarizes the cryogenic simulations involving the modeling of evaporation and condensation processes in recent years. The publication has been increasing rapidly. However, the characteristics of each evaporation and condensation model are not explicitly revealed when simulating self-pressurization. A comparative study of the phase change models is highly needed for cryogenic fluids for a better simulation of the self-pressurization processes.

In the present paper, a unified multi-phase solver incorporating four typical liquid-vapor phase change models, namely the Tanasawa model, the Lee model, the energy jump model, and the modified energy jump model has been proposed, which enables direct comparison among different models. The models are used to simulate the pressure and temperature evolutions in an experimental liquid nitrogen tank in normal gravity, which helps to evaluate themselves in the aspects of accuracy, calculation speed and robustness.

Section snippets

Governing equations for the self-pressurization tank

In the present study, both the fluid domain and the solid wall of the tank are modeled and discretized. The heat transportation at the solid boundaries is considered to be irrelevant with the nearby fluid velocity. Consequently, two sets of the solid and the fluid governing equations can be decoupled and solved separately. The pressures in the cryogenic container are usually from 100 kPa to 300 kPa. Under these conditions, the Knudsen number is far smaller than 0.01, and the fluids are

Self-pressurization results and phase change model comparison

This section compares the simulation results by different phase change models. Section 3.1 compares the pressure and temperature outputs from two KTG based models, namely the Lee model and the Tanasawa model. Section 3.2 presents the pressure predictions from the energy transport models, namely the energy jump model and the modified energy jump model, and compares pressure prediction performances between the KTG based models and the energy transport models. Section 3.3 evaluates the four models 

Conclusion

A unified vapor-liquid-solid multi-phase numerical solver has been accomplished for the self pressurization simulation in cryogenic containers. Compared to the early fluid-only solver, the temperature prediction in the vicinity of the tank wall improves significantly. Four liquid-vapor phase change models were integrated into the solver, which enables fair and effective comparison for performances between each other. The pressure and temperature prediction accuracies, and the calculation speed

CRediT authorship contribution statement

Zhongqi Zuo: Data curation, Formal analysis, Writing – original draft, Validation. Jingyi Wu: Conceptualization, Writing – review & editing, Validation. Yonghua Huang: Conceptualization, Formal analysis, Writing – review & editing, Validation.

Declaration of Competing Interest

Authors declare that they have no financial and personal relationships with other people or organizations that can inappropriately influence our work, there is no professional or other personal interest of any nature or kind in any product, service and/or company that could be construed as influencing the position presented in, or the review of, the manuscript entitled, “Validity evaluation of popular liquid-vapor phase change models for cryogenic self-pressurization process”.

Acknowledgement

This project is supported by the National Natural Science Foundation of China (No. 51936006).

References (40)

There are more references available in the full text version of this article.

Cited by (7)

Figure 3: 3D temperature contours and 2D melt pool cross-sections where the melt pool is stabilized at x=500 µm from the start of the laser initial location for cases where (a) absorptivity = 0.1, Recoil pressure coefficient B = 1 and laser beam radius = 12 µm, (b) absorptivity = 0.1, Recoil pressure coefficient B = 20 and laser beam radius = 12 µm, (c) absorptivity = 0.1, Recoil pressure coefficient B = 1 and laser beam radius = 18 µm, (d) absorptivity = 0.45, Recoil pressure coefficient B = 1 and laser beam radius = 18 µm, (e) absorptivity = 0.45, Recoil pressure coefficient B = 20 and laser beam radius = 12 µm, (f) absorptivity = 0.45, Recoil pressure coefficient B = 20 and laser beam radius = 18 µm.

MULTI-PHYSICS NUMERICAL MODELLING OF 316L AUSTENITIC STAINLESS STEEL IN LASER POWDER BED FUSION PROCESS AT MESO-SCALE

W.E. Alphonso1, M.Bayat1,*, M. Baier 2, S. Carmignato2, J.H. Hattel1
1Department of Mechanical Engineering, Technical University of Denmark (DTU), Lyngby, Denmark
2Department of Management and Engineering – University of Padova, Padova, Italy

ABSTRACT

L-PBF(Laser Powder Bed Fusion)는 레이저 열원을 사용하여 선택적으로 통합되는 분말 층으로 복잡한 3D 금속 부품을 만드는 금속 적층 제조(MAM) 기술입니다. 처리 영역은 수십 마이크로미터 정도이므로 L-PBF를 다중 규모 제조 공정으로 만듭니다.

기체 기공의 형성 및 성장 및 용융되지 않은 분말 영역의 생성은 다중물리 모델에 의해 예측할 수 있습니다. 또한 이러한 모델을 사용하여 용융 풀 모양 및 크기, 온도 분포, 용융 풀 유체 흐름 및 입자 크기 및 형태와 같은 미세 구조 특성을 계산할 수 있습니다.

이 작업에서는 용융, 응고, 유체 흐름, 표면 장력, 열 모세관, 증발 및 광선 추적을 통한 다중 반사를 포함하는 스테인리스 스틸 316-L에 대한 충실도 다중 물리학 중간 규모 수치 모델이 개발되었습니다. 완전한 실험 설계(DoE) 방법을 사용하는 통계 연구가 수행되었으며, 여기서 불확실한 재료 특성 및 공정 매개변수, 즉 흡수율, 반동 압력(기화) 및 레이저 빔 크기가 용융수지 모양 및 크기에 미치는 영향을 분석했습니다.

또한 용융 풀 역학에 대한 위에서 언급한 불확실한 입력 매개변수의 중요성을 강조하기 위해 흡수율이 가장 큰 영향을 미치고 레이저 빔 크기가 그 뒤를 잇는 주요 효과 플롯이 생성되었습니다. 용융 풀 크기에 대한 반동 압력의 중요성은 흡수율에 따라 달라지는 용융 풀 부피와 함께 증가합니다.

모델의 예측 정확도는 유사한 공정 매개변수로 생성된 단일 트랙 실험과 시뮬레이션의 용융 풀 모양 및 크기를 비교하여 검증됩니다.

더욱이, 열 렌즈 효과는 레이저 빔 크기를 증가시켜 수치 모델에서 고려되었으며 나중에 결과적인 용융 풀 프로파일은 모델의 견고성을 보여주기 위한 실험과 비교되었습니다.

Laser Powder Bed Fusion (L-PBF) is a Metal Additive Manufacturing (MAM) technology where a complex 3D metal part is built from powder layers, which are selectively consolidated using a laser heat source. The processing zone is in the order of a few tenths of micrometer, making L-PBF a multi-scale manufacturing process. The formation and growth of gas pores and the creation of un-melted powder zones can be predicted by multiphysics models. Also, with these models, the melt pool shape and size, temperature distribution, melt pool fluid flow and its microstructural features like grain size and morphology can be calculated. In this work, a high fidelity multi-physics meso-scale numerical model is developed for stainless steel 316-L which includes melting, solidification, fluid flow, surface tension, thermo-capillarity, evaporation and multiple reflection with ray-tracing. A statistical study using a full Design of Experiments (DoE) method was conducted, wherein the impact of uncertain material properties and process parameters namely absorptivity, recoil pressure (vaporization) and laser beam size on the melt pool shape and size was analysed. Furthermore, to emphasize on the significance of the above mentioned uncertain input parameters on the melt pool dynamics, a main effects plot was created which showed that absorptivity had the highest impact followed by laser beam size. The significance of recoil pressure on the melt pool size increases with melt pool volume which is dependent on absorptivity. The prediction accuracy of the model is validated by comparing the melt pool shape and size from the simulation with single track experiments that were produced with similar process parameters. Moreover, the effect of thermal lensing was considered in the numerical model by increasing the laser beam size and later on the resultant melt pool profile was compared with experiments to show the robustness of the model.

Figure 1: a) Computational domain for single track L-PBF which includes a 200 μm thick substrate and 45 μm powder layer thickness b) 3D temperature contour plot after scanning a single track with melt pool contours at two locations along the scanning direction where the green region indicates the melted regions.
Figure 1: a) Computational domain for single track L-PBF which includes a 200 μm thick substrate and 45 μm powder layer thickness b) 3D temperature contour plot after scanning a single track with melt pool contours at two locations along the scanning direction where the green region indicates the melted regions.
Figure 2: Main effects plot of uncertain parameters: absorptivity, recoil pressure coefficient and laser beam radius on the melt pool dimensions (width and depth)
Figure 2: Main effects plot of uncertain parameters: absorptivity, recoil pressure coefficient and laser beam radius on the melt pool dimensions (width and depth)
Figure 3: 3D temperature contours and 2D melt pool cross-sections where the melt pool is stabilized at x=500 µm from the start of the laser initial location for cases where (a) absorptivity = 0.1, Recoil pressure coefficient B = 1 and laser beam radius = 12 µm, (b) absorptivity = 0.1, Recoil pressure coefficient B = 20 and laser beam radius = 12 µm, (c) absorptivity = 0.1, Recoil pressure coefficient B = 1 and laser beam radius = 18 µm, (d) absorptivity = 0.45, Recoil pressure coefficient B = 1 and laser beam radius = 18 µm, (e) absorptivity = 0.45, Recoil pressure coefficient B = 20 and laser beam radius = 12 µm, (f) absorptivity = 0.45, Recoil pressure coefficient B = 20 and laser beam radius = 18 µm.
Figure 3: 3D temperature contours and 2D melt pool cross-sections where the melt pool is stabilized at x=500 µm from the start of the laser initial location for cases where (a) absorptivity = 0.1, Recoil pressure coefficient B = 1 and laser beam radius = 12 µm, (b) absorptivity = 0.1, Recoil pressure coefficient B = 20 and laser beam radius = 12 µm, (c) absorptivity = 0.1, Recoil pressure coefficient B = 1 and laser beam radius = 18 µm, (d) absorptivity = 0.45, Recoil pressure coefficient B = 1 and laser beam radius = 18 µm, (e) absorptivity = 0.45, Recoil pressure coefficient B = 20 and laser beam radius = 12 µm, (f) absorptivity = 0.45, Recoil pressure coefficient B = 20 and laser beam radius = 18 µm.
Figure 4: Validation of Numerical model with Recoil pressure coefficient B= 20, absorptivity = 0.45 and a) laser beam radius = 15 µm b) laser beam radius = 20 µm
Figure 4: Validation of Numerical model with Recoil pressure coefficient B= 20, absorptivity = 0.45 and a) laser beam radius = 15 µm b) laser beam radius = 20 µm

CONCLUSION

In this work, a high-fidelity multi-physics numerical model was developed for L-PBF using the FVM method in Flow-3D. The impact of uncertainty in the input parameters including absorptivity, recoil pressure and laser beam size on the melt pool is addressed using a DoE method. The DoE analysis shows that absorptivity has the highest impact on the melt pool. The recoil pressure and laser beam size only become significant once absorptivity is 0.45. Furthermore, the numerical model is validated by comparing the predicted melt pool shape and size with experiments conducted with similar process parameters wherein a high prediction accuracy is achieved by the model. In addition, the impact of thermal lensing on the melt pool dimensions by increasing the laser beam spot size is considered in the validated numerical model and the resultant melt pool is compared with experiments.

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Figure 2: Temperature contours and melt pool border lines at different times for the 50 % duty cycle case: (a) - (c) Δtcycle = 400 μs, (d) – (f) Δtcycle = 1000 μs and (g) – (i) Δtcycle = 3000 μs.

MULTIPHYSICS SIMULATION OF THEMRAL AND FLUID DYNAMICS PHENOMENA DURING THE PULSED LASER POWDER BED FUSION PROCESS OF 316-L STEEL

M. Bayat* , V. K. Nadimpalli, J. H. Hattel
1Department of Mechanical Engineering, Technical University of Denmark (DTU), Produktionstorvet
425, Kgs. 2800, Lyngby, Denmark

ABSTRACT

L-PBF(Laser Powder Bed Fusion)는 다양한 산업 분야에서 많은 관심을 받았으며, 주로 기존 제조 기술을 사용하여 만들 수 없었던 복잡한 토폴로지 최적화 구성 요소를 구현하는 잘 알려진 능력 덕분입니다. . 펄스 L-PBF(PL-PBF)에서 레이저의 시간적 프로파일은 주기 지속 시간과 듀티 주기 중 하나 또는 둘 다를 수정하여 변조할 수 있습니다. 따라서 레이저의 시간적 프로파일은 향후 적용을 위해 이 프로세스를 더 잘 제어할 수 있는 길을 열어주는 새로운 프로세스 매개변수로 간주될 수 있습니다. 따라서 이 작업에서 우리는 레이저의 시간적 프로파일을 변경하는 것이 PL-PBF 공정에서 용융 풀 조건과 트랙의 최종 모양 및 형상에 어떻게 영향을 미칠 수 있는지 조사하는 것을 목표로 합니다. 이와 관련하여 본 논문에서는 CFD(Computational Fluid Dynamics) 소프트웨어 패키지인 Flow-3D를 기반으로 하는 316-L 스테인리스강 PL-PBF 공정의 다중물리 수치 모델을 개발하고 이 모델을 사용하여 열과 유체를 시뮬레이션합니다. 다양한 펄스 모드에서 공정 과정 중 용융 풀 내부에서 발생하는 유동 조건. 따라서 고정된 레이저 듀티 사이클(50%)이 있는 레이저 주기 지속 시간이 용융 풀의 모양과 크기 및 최종 트랙 형태에 미치는 영향을 연구하기 위해 매개변수 연구가 수행됩니다. 더 긴 주기 기간에서 더 많은 재료가 더 큰 용융 풀 내에서 변위됨에 따라 용융 풀의 후류에 더 눈에 띄는 혹이 형성되며, 동시에 더 심각한 반동 압력을 받습니다. 또한 시뮬레이션에서 50% 듀티 사이클에서 1000μs에서 형성된 보다 대칭적인 용융 풀과 비교하여 400μs 사이클 주기에서 더 긴 용융 풀이 형성된다는 것이 관찰되었습니다. 풀 볼륨은 1000μs의 경우 더 큽니다. 매개변수 연구는 연속 트랙과 파손된 트랙 PL-PBF 사이의 경계를 설명하며, 여기서 연속 트랙은 항상 소량의 용융 재료를 유지함으로써 유지됩니다.

English Abstract

Laser Powder Bed Fusion (L-PBF) has attracted a lot of attention from various industrial sectors and mainly thanks to its well-proven well-known capacity of realizing complex topology-optimized components that have so far been impossible to make using conventional manufacturing techniques. In Pulsed L-PBF (PL-PBF), the laser’s temporal profile can be modulated via modifying either or both the cycle duration and the duty cycle. Thus, the laser’s temporal profile could be considered as a new process parameter that paves the way for a better control of this process for future applications. Therefore, in this work we aim to investigate how changing the laser’s temporal profile can affect the melt pool conditions and the final shape and geometry of a track in the PL-PBF process. In this respect, in this paper a multiphysics numerical model of the PL-PBF process of 316-L stainless steel is developed based on the computational fluid dynamics (CFD) software package Flow-3D and the model is used to simulate the heat and fluid flow conditions occurring inside the melt pool during the course of the process at different pulsing modes. Thus, a parametric study is carried out to study the influence of the laser’s cycle duration with a fixed laser duty cycle (50 %) on the shape and size of the melt pool and the final track morphology. It is noticed that at longer cycle periods, more noticeable humps form at the wake of the melt pool as more material is displaced within bigger melt pools, which are at the same time subjected to more significant recoil pressures. It is also observed in the simulations that at 50 % duty cycle, longer melt pools form at 400 μs cycle period compared to the more symmetrical melt pools formed at 1000 μs, primarily because of shorter laser off-times in the former, even though melt pool volume is bigger for the 1000 μs case. The parameteric study illustrates the boundary between a continuous track and a broken track PL-PBF wherein the continuous track is retained by always maintaining a small volume of molten material.

Figure 1: Front and side views of the computational domain. Note that the region along z and from -100 μm to +50 μm is void.
Figure 1: Front and side views of the computational domain. Note that the region along z and from -100 μm to +50 μm is void.
Figure 2: Temperature contours and melt pool border lines at different times for the 50 % duty cycle case: (a) - (c) Δtcycle = 400 μs, (d) – (f) Δtcycle = 1000 μs and (g) – (i) Δtcycle = 3000 μs.
Figure 2: Temperature contours and melt pool border lines at different times for the 50 % duty cycle case: (a) – (c) Δtcycle = 400 μs, (d) – (f) Δtcycle = 1000 μs and (g) – (i) Δtcycle = 3000 μs.
Figure 3: Plot of melt pool volume versus time for four cases including continuous wave laser as well as 50 % duty cycle at 400 μs, 1000 μs and 3000 μs.
Figure 3: Plot of melt pool volume versus time for four cases including continuous wave laser as well as 50 % duty cycle at 400 μs, 1000 μs and 3000 μs.

CONCLUSIONS

In this work a CFD model of the modulated PL-PBF process of stainless steel 316-L is developed in the commercial software package Flow-3D. The model involves physics such as solidification, melting, evaporation, convection, laser-material interaction, capillarity, Marangoni effect and the recoil pressure effect. In the current study, a parametric study is carried out to understand how the change in the cycle period duration affects the melt pool’s thermo-fluid conditions during the modulated PL-PBF process. It is observed that at the pulse mode with 50 % duty cycle and 400 μs cycle period, an overlapped chain of humps form at the wake of the melt pool and at a spatial frequency of occurrence of about 78 μm. Furthermore and as expected, it is noted that the melt pool volume, the size of the hump as well as the crater size at the end of the track, increase with increase in the cycle period duration, as more material is re-deposited at the back of the melt pool and that itself is caused by more pronounced recoil pressures. Moreover, it is noticed that due to the short off-time period of the laser in the 400 μs cycle period case, there is always an amount of liquid metal left from the previous cycle, at the time the new cycle starts. This is found to be the main reason why longer and elongated melt pools form at 400 μs cycle period, compared to the bigger, shorter and more symmetrical-like melt pools forming at the 1000 μs case. In this study PL-PBF single tracks including the broken track and the continuous track examples were studied to illustrate the boundary of this transition at a given laser scan parameter setting. At higher scan speeds, it is expected that the Plateau–Rayleigh instability will compete with the pulsing behavior to change the transition boundary between a broken and continuous track, which is suggested as future work from this study.

REFERENCES

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Heat and Mass Transfer in a Cryogenic Tank in Case of Active-Pressurization

능동 가압의 경우 극저온 탱크의 열 및 물질 전달

Heat and Mass Transfer in a Cryogenic Tank in Case of Active-Pressurization

하이라이트

헤닝 슈플러 옌스 게르스트만DLR 독일 항공 우주 센터, 우주 시스템 연구소, 28359 Bremen, Germany

상변화 및 공액 열전달을 포함하는 압축성 2상 솔버 개발.

분석 솔루션으로 솔버를 성공적으로 검증.

극저온 탱크의 압력 및 온도 변화에 대한 정확한 시뮬레이션.

자유 표면에서의 물질 전달 분석.

Abstract

압력 요구 사항을 예측하는 것은 극저온 추진 시스템의 주요 과제 중 하나입니다. 이러한 맥락에서 증발 및 응축 현상을 고려한 탱크 여압을 시뮬레이션하기 위한 수치 모델을 개발하여 적용하였습니다. 

새로운 솔버는 PISO(splitting of operator) 알고리즘이 있는 압력 암시적 방법을 기반으로 하는 OpenFOAM의 약한 압축성 다상 솔버와 기울기 기반 위상 변화 모델을 결합합니다. 날카로운 인터페이스를 유지하기 위해 인터페이스에 인접한 셀에 질량 소스 용어가 적용됩니다. 

첫째, 모델은 1차원 상 변화 문제와 중력이 없는 상태에서 과열된 액체에서 증기 기포의 성장이라는 두 가지 분석 솔루션에 대해 검증되었습니다. 

두 번째 단계에서는 검증된 모델을 극저온 가압 실험에 적용했습니다. 측정된 압력 거동은 수치 모델이 양호한 근사값으로 확인될 수 있습니다. 

수치 모델을 사용하면 물리적 거동에 대한 추가 통찰력을 얻을 수 있습니다. 응축 및 증발 효과는 가압 중 및 가압 후의 압력 발생에 상당한 영향을 미칩니다. 기액 계면에서 일어나는 상변화로 인한 질량유동은 계면의 위치와 시간에 따라 달라진다. 벽에서 직접적으로 증발이 지배적이며 액체 표면의 중앙 영역에서 응결이 발생합니다. 

응축 및 증발 효과는 가압 중 및 가압 후의 압력 발생에 상당한 영향을 미칩니다. 기액 계면에서 일어나는 상변화로 인한 질량유동은 계면의 위치와 시간에 따라 달라진다. 벽에서 직접적으로 증발이 지배적이며 액체 표면의 중앙 영역에서 응결이 발생합니다. 

응축 및 증발 효과는 가압 중 및 가압 후의 압력 발생에 상당한 영향을 미칩니다. 기액 계면에서 일어나는 상변화로 인한 질량유동은 계면의 위치와 시간에 따라 달라진다. 벽에서 직접적으로 증발이 지배적이며 액체 표면의 중앙 영역에서 응결이 발생합니다.

Predicting the pressurant requirements is one of the key challenges for cryogenic propulsion systems. In this context, a numerical model to simulate the tank pressurization that considers evaporation and condensation phenomena was developed and applied. The novel solver combines the a gradient-based phase change model with a weakly compressible multiphase solver of OpenFOAM based on the pressure implicit method with splitting of operator (PISO) algorithm. To maintain a sharp interface the mass source terms are applied to the cells adjacent to the interface. First, the model is validated against two analytical solutions: the one-dimensional phase change problem and secondly, the growth of a vapor bubble in a superheated liquid in the absence of gravity. In a second step, the validated model was applied to a cryogenic pressurization experiment. The measured pressure behavior could be confirmed with the numerical model being in a good approximation. With the numerical model further insights into the physical behavior could be achieved. The condensation and evaporation effects have a significant impact on the pressure development during and after the pressurization. The mass flows due to phase change occurring at the vapor-liquid interface depend on interface location and time. Directly at the wall, evaporation becomes dominant while condensation occurs at the center area of the liquid surface.

  1. Fig. 1. Calculation of the gradient at the interface: On the left side the interface…
  2. Fig. 2. Mass source term distribution: First the sharp mass source term ρ0, which is…
  3. Fig. 3. a) Layout of the Stefan-Problem: a vapor is located between a liquid and a…
  4. Fig. 4. Bubble in a superheated liquid: The left side depicts the calculated and…
  5. Fig. 5. Modified drawing of the dewar (as documented in [5] [6]; dimensions in mm) and…
  6. Fig. 6. Schematic presentation of the pressure evoluation in the dewar: Initial…
  7. Fig. 7. Simulation of the pressurization phase: The diagram shows the pressure…
  8. Fig. 8. Turbulent thermal diffusivity in pressurization and relaxation phase
  9. Fig. 9. Comparison of the pressure evolution in the relaxation phase of the solver with…
  10. Fig. 10. On the left side the temperature evolution in the bulk of the gas phase is shown
  11. Fig. 11. Heat Flux profile over the interface caused by evaporation with details of the…
  12. Fig. 12. Temperatures field with velocity vectors at 420 seconds after the start of the…
  13. Fig. 13. Heat transfer to the liquid from the wall and the freesurface with and without…

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키워드

Pressurization, Phase Change, CFD, Propellant Management, 가압, 상 변화, 추진제 관리

On the role of the powder stream on the heat and fluid flow conditions during Directed Energy Deposition of maraging steel-Fig3

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

MohamadBayataVenkata K.NadimpalliaFrancesco G.BiondaniaSinaJafarzadehbJesperThorborgaNiels S.TiedjeaGiulianoBissaccoaDavid B.PedersenaJesper H.Hattela
a Department of Mechanical Engineering, Technical University of Denmark, Building 425, Lyngby, Denmark
Department of Energy Conversion and Storage, Technical University of Denmark, Building 301, Lyngby, Denmark

Received 15 December 2020, Revised 12 April 2021, Accepted 19 April 2021, Available online 8 May 2021.

Abstract

The Directed Energy Deposition (DED) process of metals, has a broad range of applications in several industrial sectors. Surface modification, component repairing, production of functionally graded materials and more importantly, manufacturing of complex geometries are major DED’s applications. In this work, a multi-physics numerical model of the DED process of maraging steel is developed to study the influence of the powder stream specifications on the melt pool’s thermal and fluid dynamics conditions. The model is developed based on the Finite Volume Method (FVM) framework using the commercial software package Flow-3D. Different physical phenomena e.g. solidification, evaporation, the Marangoni effect and the recoil pressure are included in the model. As a new feature, the powder particles’ dynamics are modeled using a Lagrangian framework and their impact on the melt pool conditions is taken into account as well. In-situ and ex-situ experiments are carried out using a thermal camera and optical microscopy. The predicted track morphology is in good agreement with the experimental measurements. Besides, the predicted melt pool evolution follows the same trend as observed with the online thermal camera. Furthermore, a parametric study is carried out to investigate the effect of the powder particles incoming velocity on the track morphology. It is shown that the height-to-width ratio of tracks increases while using higher powder velocities. Moreover, it is shown that by tripling the powder particles velocity, the height-to-width ratio increases by 104% and the wettability of the track decreases by 24%.

Korea Abstract

금속의 DED (Directed Energy Deposition) 공정은 여러 산업 분야에서 광범위한 응용 분야를 가지고 있습니다. 표면 수정, 부품 수리, 기능 등급 재료의 생산 및 더 중요한 것은 복잡한 형상의 제조가 DED의 주요 응용 분야입니다.

이 작업에서는 용융 풀의 열 및 유체 역학 조건에 대한 분말 스트림 사양의 영향을 연구하기 위해 강철 마레이징 DED 공정의 다중 물리 수치 모델이 개발되었습니다. 이 모델은 상용 소프트웨어 패키지 FLOW-3D를 사용하여 FVM (Finite Volume Method) 프레임 워크를 기반으로 개발되었습니다.

다른 물리적 현상 예 : 응고, 증발, 마랑고니 효과 및 반동 압력이 모델에 포함됩니다. 새로운 기능으로 분말 입자의 역학은 Lagrangian 프레임 워크를 사용하여 모델링되며 용융 풀 조건에 미치는 영향도 고려됩니다.

현장 및 현장 실험은 열 화상 카메라와 광학 현미경을 사용하여 수행됩니다. 예측된 트랙 형태는 실험 측정과 잘 일치합니다. 게다가 예측된 용융 풀 진화는 온라인 열 화상 카메라에서 관찰된 것과 동일한 추세를 따릅니다. 또한, 분말 입자 유입 속도가 트랙 형태에 미치는 영향을 조사하기 위해 매개 변수 연구가 수행됩니다.

더 높은 분말 속도를 사용하는 동안 트랙의 높이 대 너비 비율이 증가하는 것으로 나타났습니다. 또한 분말 입자 속도를 3 배로 늘림으로써 높이 대 너비 비율이 104 % 증가하고 트랙의 젖음성은 24 % 감소하는 것으로 나타났습니다.

Keywords

Multi-physics modelDEDHeat and fluid flowFVMParticle motion

On the role of the powder stream on the heat and fluid flow conditions during Directed Energy Deposition of maraging steel-Fig
On the role of the powder stream on the heat and fluid flow conditions during Directed Energy Deposition of maraging steel-Fig
On the role of the powder stream on the heat and fluid flow conditions during Directed Energy Deposition of maraging steel-Fig2
On the role of the powder stream on the heat and fluid flow conditions during Directed Energy Deposition of maraging steel-Fig2
On the role of the powder stream on the heat and fluid flow conditions during Directed Energy Deposition of maraging steel-Fig3
On the role of the powder stream on the heat and fluid flow conditions during Directed Energy Deposition of maraging steel-Fig3
On the role of the powder stream on the heat and fluid flow conditions during Directed Energy Deposition of maraging steel-Fig4
On the role of the powder stream on the heat and fluid flow conditions during Directed Energy Deposition of maraging steel-Fig4
On the role of the powder stream on the heat and fluid flow conditions during Directed Energy Deposition of maraging steel-Fig5
On the role of the powder stream on the heat and fluid flow conditions during Directed Energy Deposition of maraging steel-Fig5
On the role of the powder stream on the heat and fluid flow conditions during Directed Energy Deposition of maraging steel-Fig6
On the role of the powder stream on the heat and fluid flow conditions during Directed Energy Deposition of maraging steel-Fig6
On the role of the powder stream on the heat and fluid flow conditions during Directed Energy Deposition of maraging steel-Fig7
On the role of the powder stream on the heat and fluid flow conditions during Directed Energy Deposition of maraging steel-Fig7
On the role of the powder stream on the heat and fluid flow conditions during Directed Energy Deposition of maraging steel-Fig8
On the role of the powder stream on the heat and fluid flow conditions during Directed Energy Deposition of maraging steel-Fig8
On the role of the powder stream on the heat and fluid flow conditions during Directed Energy Deposition of maraging steel-Fig9
On the role of the powder stream on the heat and fluid flow conditions during Directed Energy Deposition of maraging steel-Fig9
On the role of the powder stream on the heat and fluid flow conditions during Directed Energy Deposition of maraging steel-Fig10
On the role of the powder stream on the heat and fluid flow conditions during Directed Energy Deposition of maraging steel-Fig10
On the role of the powder stream on the heat and fluid flow conditions during Directed Energy Deposition of maraging steel-Fig11
On the role of the powder stream on the heat and fluid flow conditions during Directed Energy Deposition of maraging steel-Fig11
Fig. 9 (a) Velocity field, keyhole profile, and breakage of the keyhole to form bubble and (b) 2D temperature and velocity field along the longitudinal section

A Numerical Study on the Keyhole Formation During Laser Powder Bed Fusion Process

Keyhole에 대한 수치적 연구 : 레이저 분말 중 형성 베드 퓨전 공정

Subin Shrestha1
J.B. Speed School of Engineering,University of Louisville,Louisville, KY 40292
e-mail: subin.shrestha@louisville.edu

Y. Kevin Chou
J.B. Speed School of Engineering,University of Louisville,Louisville, KY 40292
e-mail: kevin.chou@louisville.edu

LPBF (Laser Powder Bed fusion) 공정 중 용융 풀의 동적 현상은 복잡하고 공정 매개 변수에 민감합니다. 에너지 밀도 입력이 특정 임계 값을 초과하면 키홀이라고 하는 거대한 증기 함몰이 형성 될 수 있습니다.

이 연구는 수치 분석을 통해 LPBF 과정에서 키홀 거동 및 관련 기공 형성을 이해하는 데 중점을 둡니다. 이를 위해 이산 분말 입자가 있는 열 유동 모델이 개발되었습니다.

이산 요소 방법 (DEM)에서 얻은 분말 분포는 계산 영역에 통합되어 FLOW-3D를 사용하는 3D 프로세스 물리학 모델을 개발합니다.

전도 모드 중 용융 풀 형성과 용융의 키홀 모드가 식별되고 설명되었습니다. 높은 에너지 밀도는 증기 기둥의 형성으로 이어지고 결과적으로 레이저 스캔 트랙 아래에 구멍이 생깁니다.

또한 다양한 레이저 출력과 스캔 속도로 인한 Keyhole 모양을 조사합니다. 수치 결과는 동일한 에너지 밀도에서도 레이저 출력이 증가함에 따라 Keyhole크기가 증가 함을 나타냅니다. Keyhole은 더 높은 출력에서 ​​안정되어 레이저 스캔 중 Keyhole 발생을 줄일 수 있습니다.

The dynamic phenomenon of a melt pool during the laser powder bed fusion (LPBF) process is complex and sensitive to process parameters. As the energy density input exceeds a certain threshold, a huge vapor depression may form, known as the keyhole. This study focuses on understanding the keyhole behavior and related pore formation during the LPBF process through numerical analysis. For this purpose, a thermo-fluid model with discrete powder particles is developed. The powder distribution, obtained from a discrete element method (DEM), is incorporated into the computational domain to develop a 3D process physics model using flow-3d. The melt pool formation during the conduction mode and the keyhole mode of melting has been discerned and explained. The high energy density leads to the formation of a vapor column and consequently pores under the laser scan track. Further, the keyhole shape resulted from different laser powers and scan speeds is investigated. The numerical results indicated that the keyhole size increases with the increase in the laser power even with the same energy density. The keyhole becomes stable at a higher power, which may reduce the occurrence of pores during laser scanning.

Keywords: additive manufacturing, keyhole, laser powder bed fusion, porosity

Fig. 1 (a) Powder added to the dispenser platform and (b) powder particles settled over build plate after the recoating process
Fig. 1 (a) Powder added to the dispenser platform and (b) powder particles settled over build plate after the recoating process
Fig. 2 3D computational domain used for single-track simulation
Fig. 2 3D computational domain used for single-track simulation
Fig. 3 Temperature-dependent material properties of Ti-6Al-4V
Fig. 3 Temperature-dependent material properties of Ti-6Al-4V
Fig. 4 Powder and substrate melting during laser application
Fig. 4 Powder and substrate melting during laser application
Fig. 5 Melt region formed after complete melting and solidification
Fig. 5 Melt region formed after complete melting and solidification
Fig. 6 Melt pool boundary comparison between the experiment [25] and the simulation
Fig. 6 Melt pool boundary comparison between the experiment [25] and the simulation
Fig. 7 Equilibrium points during the formation of vapor column [27]
Fig. 7 Equilibrium points during the formation of vapor column [27]
Fig. 8 Multiple reflection vectors from the keyhole wall
Fig. 8 Multiple reflection vectors from the keyhole wall
Fig. 9 (a) Velocity field, keyhole profile, and breakage of the keyhole to form bubble and (b) 2D temperature and velocity field along the longitudinal section
Fig. 9 (a) Velocity field, keyhole profile, and breakage of the keyhole to form bubble and (b) 2D temperature and velocity field along the longitudinal section
Fig. 10 Fluid flow in the transverse direction during keyhole melting
Fig. 10 Fluid flow in the transverse direction during keyhole melting
Fig. 11 Melt pool boundary compared with the experiment [21] for 195 W laser power and 400 mm/s scan speed
Fig. 11 Melt pool boundary compared with the experiment [21] for 195 W laser power and 400 mm/s scan speed
Fig. 12 Melt region formed after complete melting and solidification
Fig. 12 Melt region formed after complete melting and solidification
Fig. 13 2D images of the pores formed at the beginning of the single track and their 3D-rendered morphology
Fig. 13 2D images of the pores formed at the beginning of the single track and their 3D-rendered morphology
Fig. 14 Pore number and volume from a different level of power with LED = 0.4 J/mm [29]
Fig. 14 Pore number and volume from a different level of power with LED = 0.4 J/mm [29]
Fig. 15 Keyhole shape at different time steps from different parameters: (a) P = 100 W, v = 250 mm/s, (b) P = 200 W, v = 500 mm/s, (c) P = 300 W, v = 750 mm/s, and (d) P = 400 W, v = 1000 mm/s
Fig. 15 Keyhole shape at different time steps from different parameters: (a) P = 100 W, v = 250 mm/s, (b) P = 200 W, v = 500 mm/s, (c) P = 300 W, v = 750 mm/s, and (d) P = 400 W, v = 1000 mm/s
Fig. 16 Intensity dependence in the relationship between vapor column and evaporation pressure [27]
Fig. 16 Intensity dependence in the relationship between vapor column and evaporation pressure [27]
Fig. 17 Temperature distribution when laser has moved 0.8 mm with P = 300 W, v = 750 mm/s and P = 400 W, v = 1000 mm/s
Fig. 17 Temperature distribution when laser has moved 0.8 mm with P = 300 W, v = 750 mm/s and P = 400 W, v = 1000 mm/s
Fig. 18 Melt region with different level of power with LED of 0.4 J/mm
Fig. 18 Melt region with different level of power with LED of 0.4 J/mm

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Figure 2.6 ESI apparatus for offline analysis with microscope imaging.

MODELING AND CHARACTERIZATION OF MICROFABRICATED EMITTERS: IN PURSUIT OF IMPROVED ESI-MS PERFORMANCE

미세 가공 방사체의 모델링 및 특성화 : 개선된 ESI-MS 성능 추구

by XINYUN WU

A thesis submitted to the Department of Chemistry in conformity with the requirements for the degree of Master of Science Queen’s University Kingston, Ontario, Canada December, 2011 Copyright © Xinyun Wu, 2011

Abstract

ESI (Electrospray ionization)는 특히 탁월한 감도, 견고성 및 단순성으로 대형 생체 분자를 분석하는 데있어 질량 분석 (MS)에 매우 귀중한 기술이었습니다. ESI 기술 개발에 많은 노력을 기울였습니다. 그 형태와 기하학적 구조가 전기 분무 성능과 추가 MS 감지에 중추적 인 것으로 입증 되었기 때문입니다.

막힘 및 낮은 처리량을 포함하여 전통적인 단일 홀 이미터의 본질적인 문제는 기술의 적용 가능성을 제한합니다. 이 문제를 해결하기 위해 현재 프로젝트는 향상된 ESI-MS 분석을위한 다중 전자 분무(MES) 방출기를 개발하는데 초점을 맞추고 있습니다.

이 논문에서는 스프레이 전류 측정을 위한 전기 분무와 오프라인 전기 분무 실험을 위한 전산 유체 역학 (CFD) 시뮬레이션의 공동 작업이 수행되었습니다. 전기 분무 성능에 대한 다양한 이미터 설계의 영향을 테스트하기 위해 수치 시뮬레이션이 사용되었으며 실험실 결과는 가이드 및 검증으로 사용되었습니다.

CFD 코드는 Taylor-Melcher 누설 유전체 모델(LDM)을 기반으로 하며 과도 전기 분무 공정이 성공적으로 시뮬레이션되었습니다.

이 방법은 750 μm 내경 (i.d.) 이미 터를 통해 먼저 검증되었으며 20 μm i.d.에 추가로 적용되었습니다. 모델. 전기 분무 공정의 여러 단계가 시각적으로 시연되었으며 다양한 적용 전기장 및 유속에서 분무 전류의 변화에 ​​대한 정량적 조사는 이전 시뮬레이션 및 측정과 잘 일치합니다.

단일 조리개 프로토 타입을 기반으로 2 홀 및 3 홀 이미터로 MES 시뮬레이션을 수행했습니다. 시뮬레이션 예측은 실험 결과와 유사하게 비교되었습니다. 이 작업의 증거는 CFD 시뮬레이션이 MES의 이미 터 설계를 테스트하는 효과적인 수치 도구로 사용될 수 있음을 입증했습니다.

이 작업에서 달성 된 마이크로 스케일 에미 터 전기 분무의 성공적인 시뮬레이션에 대한 벤치마킹 결과는 현재까지 발표 된 전기 분무에 대한 동적 시뮬레이션의 가장 작은 규모로 여겨집니다.

Co-Authorship

공동 저자: 이 논문에 대한 모든 연구는 Natalie M. Cann 박사와 Richard D. Oleschuk 박사의 지도하에 완료되었습니다. 다중 전자 분무에 관한 4 장에서 제시된 연구 작업의 일부는 Ramin Wright가 공동 저술했으며, 이 작업은 press에서 다음 논문에서 인용되었습니다.

ibson,G.T.T.; Wright, R.D.; Oleschuk, R.D. Multiple electrosprays generated from a single poly carbonate microstructured fibre. Journal of Mass Spectrometry, 2011, in press.

Chapter 1 Introduction

소프트 이온화 방법으로 ESI (electrospray ionization)의 도입은 질량 분석법 (MS)의 적용 가능성에 혁명을 일으켰습니다. 이 기술의 부드러운 특징은 상대적으로 높은 전하를 가진 이온을 생성하는 고유한 이점으로 인해 액상에서 직접 펩티드 및 단백질과 같은 큰 생체 분자를 분석 할 수 있게했습니다 [1].

지난 10 년 동안 ESI-MS는 놀라운 성장을 보였으며 현재는 단백질 체학, 대사 체학, 글리코 믹스, 합성 화학자를 위한 식별 도구 등 다양한 생화학 분야에서 광범위하게 채택되고 있습니다 [2-3].

ESI-MS는 겔 전기 영동과 같은 생물학적 분자에 대한 기존의 질량 측정 기술보다 훨씬 빠르고 민감하며 정확합니다. 또한, 액체상에서 직접 분석 할 수 있는 큰 비 휘발성 분자의 능력은 고성능 액체 크로마토 그래피 (HPLC) 및 모세관 전기 영동 (CE)과 같은 업스트림 분리 기술과의 결합을 가능하게합니다 [4].

일반적인 ESI 공정은 일반적으로 액적 형성, 액적 수축 및 기상 이온의 최종 형성을 포함합니다. 일렉트로 스프레이의 성능에 영향을 미치는 많은 요소 중에서 스프레이를 위한 이미터의 구조 (즉, 기하학, 모양 등)가 중요한 요소입니다.

전통적인 전기 분무 이미터는 일반적으로 풀링 또는 에칭 기술로 제작 된 단일 채널 테이퍼 형 또는 비 테이퍼 형입니다. 그러나 이러한 이미터는 종종 막힘, 부적절한 처리량 등과 같은 문제로 어려움을 겪습니다. [5]

향상된 감도 및 샘플 활용을 위해 다중 스프레이를 생성하는 새로운 이미터 설계 개발로 분명한 발전이 있었습니다. 새로운 ESI 이미터 설계에 대한 연구는 실험적으로나 이론적으로 큰 관심을 불러 일으켰습니다 [3]. 그러나 ESI의 복잡한 물리적 과정은 팁 형상 외에도 많은 다른 변수에 의존하기 때문에 연구간 직접 비교의 어려움은 장애물이 됩니다.

또한 새로운 나노 이미터 제조 및 테스트 비용이 상당히 높을 수 있습니다. 이 논문은 CFD 시뮬레이션 도구를 활용하여 가상 랩을 설정함으로써 이러한 문제를 해결합니다. 다른 매개 변수로 인해 상호 연결된 변경 없이 다양한 이미터 설계를 비교할 수 있도록 이상적으로 균일한 물리적 조건을 제공합니다.

맞춤 제작된 프로토 타입의 실험 측정 값도 수집되어 더 나은 계산 체계를 형성하는 데 도움이 되는 지침과 검증을 모두 제공합니다. 특히 이 분야의 주요 미래 플랫폼으로 여겨지는 다중 노즐 이미 터 설계에 중점을 둘 것입니다.

전기 분무 거동에 영향을 미치는 요인에 대한 추가 기본 연구는 다양한 기하학적 및 작동 매개 변수와 관련하여 수행됩니다. 이는 보다 효율적이고 견고한 이미터의 개발을 가능하게 할 뿐만 아니라 더 넓은 영역에서 ESI의 적용을 향상시킬 수 있습니다.

Figure 1.1Schematic setup for ESI-MS technique
Figure 1.1Schematic setup for ESI-MS technique
Figure 1.2 Schematic of major processes occurring in electrospray [5].
Figure 1.2 Schematic of major processes occurring in electrospray [5].
Figure 1.3 Illustration of detailed geometric parameters of a spraying Taylor cone wherera is the radius of curvature of the best fitting circle at the tip of the cone; re is the radius of the emission region for droplets at the tip of a Taylor cone;is the liquid cone angle.
Figure 1.3 Illustration of detailed geometric parameters of a spraying Taylor cone wherera is the radius of curvature of the best fitting circle at the tip of the cone; re is the radius of the emission region for droplets at the tip of a Taylor cone;is the liquid cone angle.
Figure 1.4 (A)Externally tapered emitter  (B) Optical image of a clogged tapered emitter with normal use [46].
Figure 1.4 (A)Externally tapered emitter (B) Optical image of a clogged tapered emitter with normal use [46].
Figure 1.5 (A)Three by three configuration of an emitter array made with polycarbonate using laser ablation; (B) Photomicrograph of nine stable electrosprays generated from the nine-emitter array [52]
Figure 1.5 (A)Three by three configuration of an emitter array made with polycarbonate using laser ablation; (B) Photomicrograph of nine stable electrosprays generated from the nine-emitter array [52]
Figure 1.6 SEM images of the distal ends of four multichannel nanoelectrospray emitters and a tapered emitter: (A) 30 orifice emitter; (B) 54 orifice emitter; (C) 84 orifice emitter; (D) 168 orifice emitter; Scale bars in A, B, and C represent 50 μm, and 100 μm in D[54]
Figure 1.6 SEM images of the distal ends of four multichannel nanoelectrospray emitters and a tapered emitter: (A) 30 orifice emitter; (B) 54 orifice emitter; (C) 84 orifice emitter; (D) 168 orifice emitter; Scale bars in A, B, and C represent 50 μm, and 100 μm in D[54]
Figure 1.7 Photomicrographs of electrospray from of a 168-hole MCN emitter at different flow rates. (A) A traditional integrated Taylor cone observed from offline electrospray of water with 0.1% formic acid at 300 nL/min; (B) A mist of coalesced Taylor cones observed from offline electrospray at 25 nL/min[54]
Figure 1.7 Photomicrographs of electrospray from of a 168-hole MCN emitter at different flow rates. (A) A traditional integrated Taylor cone observed from offline electrospray of water with 0.1% formic acid at 300 nL/min; (B) A mist of coalesced Taylor cones observed from offline electrospray at 25 nL/min[54]
Figure 1.8 Circular arrays of etched emitters for better electric field homogeneity [53].
Figure 1.8 Circular arrays of etched emitters for better electric field homogeneity [53].
Figure 2.6 ESI apparatus for offline analysis with microscope imaging.
Figure 2.6 ESI apparatus for offline analysis with microscope imaging.
Figure 3.9 Typical panel for displaying instant simulation result during simulation process.
Figure 3.9 Typical panel for displaying instant simulation result during simulation process.
Figure 5.3 Generation of a Taylor cone-jet mode (simulation) plotted with iso-potential lines at times    (Top to bottom panels correspond to 0.002 s, 0.012 s, 0.018 s, 0.08 s respectively).
Figure 5.3 Generation of a Taylor cone-jet mode (simulation) plotted with iso-potential lines at times (Top to bottom panels correspond to 0.002 s, 0.012 s, 0.018 s, 0.08 s respectively).
Figure 5.8 (A) Taylor cone-jet profiles with different contact angle of 30 degrees and 20 degrees (B) under the same physical conditions of 6 kV and 0.04 m/s. (C) Cone-jet profile generated from a tapered tip with a 20 degree contact angle at 6 kV and 0.04 m/s (as a comparison with (B)).
Figure 5.8 (A) Taylor cone-jet profiles with different contact angle of 30 degrees and 20 degrees (B) under the same physical conditions of 6 kV and 0.04 m/s. (C) Cone-jet profile generated from a tapered tip with a 20 degree contact angle at 6 kV and 0.04 m/s (as a comparison with (B)).

Omit below: Please refer to the original text for the full content.

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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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레이저 용접 수치해석 (FLOW-3D WELD)

FLOW-3D WELD Products

레이저 용접 수치해석 (FLOW-3D WELD)

FLOW-3D@ WELD는 레이저 용접 공정에 대한 정확한 시뮬레이션 기능을 제공하여 최적화된 공정을 개발하게 합니다. 더 나은 공정 제어를 통해 기공, 열 영향 영역을 최소화하고 미세 구조 변화를 제어할 수 있습니다.

레이저 용접 프로세스를 정확하게 시뮬레이션하기 위해 FLOW-3D@ WELD는 레이저 열원, 레이저-재료 상호 작용, 유체 흐름, 열 전달, 표면 장력, 응고, 다중 레이저 반사 및 위상 변화와 같은 모든 관련 물리 모델을 제공합니다.

Laser Welding

최근에는 뛰어난 생산성과 속도, 낮은 열 입력이 결합되어 기존의 용접 프로세스를 대체하는 레이저 용접 프로세스가 주목 받고 있습니다. 레이저 용접이 제공하는 장점은 용접강도가 좋고, 열 영향 부위가 작으며, 정밀도가 낮고 변형이 적으며, 강철, 알루미늄, 티타늄 및 이종 금속을 포함한 광범위한 금속 및 합금을 용접 할 수 있는 기능이 있습니다.

FLOW-3D@는 레이저 용접 공정에 대한 강력한 통찰력을 제공하고 궁극적으로 프로세스 최적화를 달성하는 데 도움이 됩니다.

보다 나은 프로세스 제어를 통해 기공을 최소화할 수 있습니다. 열 영향부위 및 미세조직을 제어가 가능합니다. FLOW-3D는 자유표면 추적 알고리즘을 통해 매우 복잡한 용접 POOL 시뮬레이션을 해석하는데 매우 적합합니다.

용접 모듈은 레이저 소스에 의해 생성된 Heat flux, 용융 금속에 대한 증발압력, shield gas 효과, 용융 풀의 반동압력 및 다중 레이저 반사와 같은 물리적 모델을 FLOW-3D에 적용하기 위해 개발되었습니다. 키홀 용접과 같은 현실적인 프로세스 시뮬레이션을 위해서는 모든 관련 물리적 현상을 적용하는 것이 중요합니다.

FLOW-3D는 레이저 용접의 conduction and keyhole 방식을 시뮬레이션 할 수 있습니다. 전 세계의 연구원들은 FLOW-3D를 사용하여 용접역학을 분석하고, 공정 매개 변수를 최적화하여 기공을 최소화하며, 레이저 용접공정에서의 dendrite 결정 성장 양상을 예측합니다.

Shallow penetration weld (top left); deep penetration weld with shield gas effects (top right); deep penetration weld with shield gas and evaporation pressure (bottom left); and deep penetration weld with shield gas, evaporation pressure and multiple laser reflections effects (bottom right).

Full Penetration Laser Welding Experiments

한국 카이스트와 독일 BAM은 16K kW레이저를 사용하여 10mm강판에 완전 침투 레이저 용접 실험을 수행하였습니다. CCD카메라의 도움을 받아 완전 용입 레이저 용접으로 형성된 상단 및 하단 용융풀 거동을 확인할 수 있었습니다. 그들은 또한 FLOW-3D 로 용접 공정 해석으로 해석과 실험결과의 경향이 일치하는 것을 알 수 있었습니다.

Experimental setup with CCD cameras observing the top and bottom molten pools
Schematic of computation domain in FLOW-3D

 

Simulation results at the top show melt pool lengths of 8mm and 15mm, whereas experiments indicated melt pool lengths of 7mm and 13mm

Laser Welding Porosity Case Study

General Motors, Michigan, 중국의 상하이 대학교는 용접 공정 변수, 즉 keyhole 용접에서 기공의 발생에 대해 용접 속도 및 용접 각도와 같은 공정 매개 변수가 미치는 영향을 알아보기 위해 협력하여 연구를 진행하였습니다.

레이저 용접된 Al 접합부 단면의 기공을 분석합니다. Keyhole이 유도 된 기공들은 유동 역학으로 인해 발생되고 균열을 일으킬 수 있습니다. 최적화 공정의 매개변수는 이러한 종류의 기공을 완화할 수 있습니다. FLOW-3D를 사용하여 연구원들은 증발 및 반동 압력, 용융풀, 온도에 따른 표면장력 및 Keyhole내의 다중 레이저 반사, 프레넬 흡수를 포함한 모든 중요한 물리적 현상을 설명했습니다.

연구진은 시뮬레이션 모델을 기반으로 Keyhole 용접에서 생성된 기공들의 주요 원인으로 불안정한 Keyhole을 규정하였습니다. 아래 이미지에서 볼 수 있듯이 뒤쪽 용융 풀의 과도한 재순환은 뒤쪽 용융 풀이 앞쪽 용융 풀 경계를 무너뜨리며 기공들을 생성시킵니다. 갇힌 공간이 증가하는 응고 전면에 의해 갇혔을때 기공들이 발생되었습니다.

Distribution of porosity in longitudinal welding sections as seen in simulations (top) and experiments (bottom)

용접 속도가 빠를수록 더 큰 keyhole이 생성되며 이로 인해, 보다 안정적인 keyhole이 생성됩니다. 연구진은 FLOW-3D를 사용하여 용접 속도와 용접 경사각으로 기공들의 생성을 완화시킬 수 있었습니다.


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The realm of operations of FLOW-3D

ADDITIVE MANUFACTURING SIMULATIONS

Capabilities of FLOW-3D

FLOW-3D는 자유 표면 유체 흐름 시뮬레이션을 전문으로하는 다중 물리 CFD 소프트웨어입니다. 자유 표면의 동적 진화를 추적하는 소프트웨어의 알고리즘인 VOF (Volume of Fluid) 방법은 Flow Science의 설립자인 Tony Hirt 박사가 개척했습니다.

또한 FLOW-3D에는 금속 주조, 잉크젯 인쇄, 레이저 용접 및 적층 제조 (AM)와 같은 광범위한 응용 분야를 시뮬레이션하기위한 물리 모델이 내장되어 있습니다.
적층 제조 시뮬레이션 소프트웨어, 특히 L-PBF (레이저 파우더 베드 융합 공정)의 현상 유지는 열 왜곡, 잔류 응력 및지지 구조 생성과 같은 부분 규모 모델링에 도움이되는 열 기계 시뮬레이션에 초점을 맞추고 있습니다.

유용하지만 용융 풀 역학 및 볼링 및 다공성과 같은 관련 결함에 대한 정보는 일반적으로 이러한 접근 방식의 영역 밖에 있습니다. 용융 풀 내의 유체 흐름, 열 전달 및 표면 장력이 열 구배 및 냉각 속도에 영향을 미치며 이는 다시 미세 구조 진화에 영향을 미친다는 점을 명심하는 것도 중요합니다.

FLOW-3D와 이산 요소법 (DEM) 및 WELD 모듈을 사용하여 분말 및 용융 풀 규모에서 시뮬레이션 할 수 있습니다.
구현되는 관련 물리학에는 점성 흐름, 열 전달, 응고, 상 변화, 반동 압력, 차폐 가스 압력, 표면 장력, 움직이는 물체 및 분말 / 입자 역학이 포함됩니다. 이러한 접근 방식은 합금에 대한 공정을 성공적으로 개발할 수 있게 하고, AM 기계 제조업체와 AM 기술의 최종 사용자 모두에게 관심있는 미세 구조 진화에 대한 통찰력을 제공하는데 도움이 됩니다.

The realm of operations of FLOW-3D
The realm of operations of FLOW-3D

FLOW-3D는 레이저 분말 베드 융합 (L-PBF), 직접 에너지 증착 (DED) 및 바인더 제트 공정으로 확장되는 기능을 가지고 있습니다.
FLOW-3D를 사용하면 분말 확산 및 패킹, 레이저 / 입자 상호 작용, 용융 풀 역학, 표면 형태 및 후속 미세 구조 진화를 정확하게 시뮬레이션 할 수 있습니다. 이러한 기능은 FLOW-3D에 고유하며 계산 효율성이 높은 방식으로 달성됩니다.

예를 들어 1.0mm x 0.4mm x 0.3mm 크기의 계산 영역에서 레이저 빔의 단일 트랙을 시뮬레이션하기 위해 레이저 용융 모델은 단 8 개의 물리적 코어에서 약 2 시간이 걸립니다.
FLOW-3D는 모든 관련 물리 구현 간의 격차를 해소하는 동시에 업계 및 연구 표준에서 허용하는 시간 프레임으로 결과를 생성합니다. 분말 패킹, 롤러를 통한 파워 확산, 분말의 레이저 용융, 용융 풀 형성 및 응고를 고려하고 다층 분말 베드 융합 공정을 위해 이러한 단계를 순차적으로 반복하여 FLOW-3D에서 전체 AM 공정을 시뮬레이션 할 수 있습니다.

FLOW-3D의 다층 시뮬레이션은 이전에 응고된 층의 열 이력을 저장한다는 점에서 독특하며, 열 전달을 고려하여 이전에 응고된 층에 확산된 새로운 분말 입자 세트에 대해 시뮬레이션이 수행됩니다.
또한, 응고 된 베드의 열 왜곡 및 잔류 응력은 FLOW-3D를 사용하여 평가할 수 있으며, 보다 복잡한 분석을 수행하기 위해 FLOW-3D의 압력 및 온도 데이터를 Abaqus 및 MSC Nastran과 같은 FEA 소프트웨어로 내보낼 수 있습니다.

Sequence of a multi-layer L-PBF simulation setup in FLOW-3D

Ease of Use

FLOW-3D는 다양한 응용 분야에서 거의 40 년 동안 사용되어 왔습니다. 사용자 피드백을 기반으로 UI 개발자는 소프트웨어를 사용하기 매우 직관적으로 만들었으며 새로운 사용자는 시뮬레이션 설정의 순서를 거의 또는 전혀 어려움없이 이해합니다.
사용자는 FLOW3D에서 구현 된 다양한 모델의 이론에 정통하며 새로운 실험을 설계 할 수 있습니다. 실습 튜토리얼, 비디오 강의, 예제 시뮬레이션 및 기술 노트의 저장소도 사용할 수 있습니다.
사용자가 특정 수준의 경험에 도달하면 고급 수치 교육 및 소프트웨어 사용자 지정 교육을 사용할 수 있습니다.

Available Literature

실험 데이터에 대해 FLOW-3D 모델을 검증하는 몇 가지 독립적으로 발표된 연구가 있습니다. 여기에서 수록된 저널 논문은 레이저 용접 및 적층 제조 공정으로 제한됩니다. 더 많은 참조는 당사 웹 사이트에서 확인할 수 있습니다.

Laser Welding

  1. L.J.Zhang, J.X.Zhang, A.Gumenyuk, M.Rethmeier, 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, Volume 214, Issue 8, 2014.
    A study by researchers from BAM in Germany, KAIST in Korea, and State Key Laboratory of Mechanical Behavior of Materials in China that focuses on keyhole dynamics and full penetration laser welding of steel plates.
  2. 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, Volume 108, Part A, 2017.
    General Motors (GM) and Shangai University collaborated on a study on the influence of welding speed and weld angle of inclination on porosity occurrence in laser keyhole welding.
  3. Koji Tsukimoto, Masashi Kitamura, Shuji Tanigawa, Sachio Shimohata, and Masahiko Mega, Laser Welding Repair for Single Crystal Blades, International Gas Turbine Congress, Tokyo, 2015.
    Mitsubishi Heavy Industry’s study on laser welding repair using laser cladding for single Ni crystal alloys used in gas turbine blades.

Additive Manufacturing

  1. Yu-Che Wu, Cheng-Hung San, Chih-Hsiang Chang, Huey-Jiuan Lin, Raed Marwan, Shuhei Baba, Weng-Sing Hwang, Numerical modeling of melt-pool behavior in selective laser melting with random powder distribution and experimental validation, Journal of Materials Processing Technology, Volume 254, 2018
    This paper discusses powder bed compaction with random packing for different powder-size distributions, and the importance of considering evaporation effects in the melting process to validate the melt pool dimensions.
  2. Lee, Y.S., and W.Zhang, Mesoscopic simulation of heat transfer and fluid flow in laser powder bed additive manufacturing, Proceedings of the Annual International Solid Freeform Fabrication Symposium, Austin, TX, USA. 2015
    A study conducted by Ohio State University researchers to understand the influence of process parameters in formation of balling defects.
  3. Y.S. Lee, W.Zhang, Modeling of heat transfer, fluid flow and solidification microstructure of nickel-base superalloy fabricated by laser powder bed fusion, Additive Manufacturing, Volume 12, Part B, 2016
    A study conducted by Ohio State University researchers to understand the influence of solidification parameters, calculated from the temperature fields, on solidification morphology and grain size using existing theoretical models in laser powder bed fusion processes.

 

 

레이저 용접 수치해석(FLOW WELD)

Laser Welding

뛰어난 생산성과 속도, 낮은 열 입력이 결합되어 기존의 용접 프로세스를 대체하는 레이저 용접 프로세스가 있습니다. 레이저 용접이 제공하는 장점은 용접강도가 좋고, 열 영향 부위가 작으며, 정밀도가 높고 변형이 적으며 강철, 알루미늄, 티타늄 및 이종 금속을 포함한 광범위한 금속 및 합금을 용접 할 수 있는 기능이 있습니다.

FLOW-3D는 레이저 용접 공정에 대한 강력한 통찰력을 제공하고 궁극적으로 프로세스 최적화를 달성하는 데 도움이 됩니다. 보다 나은 프로세스 제어를 통해 다공성을 최소화할 수 있습니다. 열 영향부위 및 마이크로-구조를 제어합니다. FLOW-3D는 자유표면 추적 알고리즘으로 인해 매우 복잡한 용접 풀 시뮬레이션을 해석하는데 적합합니다. 용접의 추가 모듈은 레이저 소스에 의해 생성된 Heat flux, 용융 금속에 대한 증발압력, shield gas효과, 용융 풀의 반동압력 및 다중 레이저반사와 같은 물리적 모델을 FLOW-3D에 통합하기 위해 개발되었습니다. Keyhole 용접과 같은 현실적인 프로세스 시뮬레이션을 위해서는 모든 관련 물리적 현상을 포착하는 것이 중요합니다.

FLOW-3D는 레이저 용접의 conduction and keyhole 방식을 시뮬레이션 할 수 있습니다. 전 세계의 연구원들은 FLOW-3D를 사용하여 용접역학을 분석하고, 공정 매개 변수를 최적화하여 다공성을 최소화하며, 레이저 용접공정의 수지결정 성장을 예측합니다.

Shallow penetration weld (top left); deep penetration weld with shield gas effects (top right); deep penetration weld with shield gas and evaporation pressure (bottom left); and deep penetration weld with shield gas, evaporation pressure and multiple laser reflections effects (bottom right).

Full Penetration Laser Welding Experiments

한국 카이스트와 독일 BAM은 16KW레이저를 사용하여 10mm강판에 완전 침투 레이저 용접 실험을 수행하였습니다. CCD카메라의 도움을 받아 완전 용입 레이저 용접으로 형성된 상단 및 하단 용융지 역학을 포착할 수 있었습니다. 그들은 또한 FLOW-3D공정을 시뮬레이션하여 해석과 실험결과가 경향이 일치하는 것을 나타내었습니다.

Experimental setup with CCD cameras observing the top and bottom molten pools
 
Simulation results at the top show melt pool lengths of 8mm and 15mm, whereas experiments indicated melt pool lengths of 7mm and 13mm
 
 
 
 
Schematic of computation domain in FLOW-3D

 

Laser Welding Porosity Case Study

General Motors, Michigan, 중국의 상하이 대학교는 공정변수, 즉 keyhole 용접에서 다공성 발생 에 대해 용접속도 및 용접각도와 같은 공정 매개 변수가 미치는 영향을 이해하기 위해 협력하여 연구를 진행하였습니다.

 
레이저 용접된 Al 접합부 단면의 다공성을 용접합니다. Keyhole 유도 된 다공성은 유동 역학으로 인해 발생되고 균열을 일으킬 수 있습니다. 최적화 공정의 매개변수는 이러한 종류의 다공성을 완화할 수 있습니다. FLOW-3D를 사용하여 연구원들은 증발 및 반동 압력, 용융풀, 온도에 따른 표면장력 및 Keyhole내의 다중 레이저 반사, 프레넬 흡수를 포함한 모든 중요한 물리적 현상을 설명했습니다.

연구진은 시뮬레이션 모델을 기반으로 Keyhole용접에서 유도된 다공성의 주요 원인으로 불안정한Keyhole을 규정하였습니다. 아래 이미지에서 볼 수 있듯이 뒤쪽 용융 풀의 과도한 재순환은 뒤쪽 용융 풀이 앞쪽 용융 풀 경계를 무너뜨리며 다공성을 초래시킵니다. 갇힌 공간이 증가하는 응고 전면에 의해 포착되었을 때 다공성이 유도되었습니다.

용접 속도가 빠를수록 더 큰 keyhole이 생성되며 이로 인해보다 안정적인 keyhole이 구성됩니다. 연구진은 FLOW-3D를 사용하여 높은 용접 속도와 큰 용접 경사각으로 다공성을 완화시킬 수 있다고 예측했습니다.

 
 
Distribution of porosity in longitudinal welding sections as seen in simulations (top) and experiments (bottom)

용접분야 활용

Conduction 용접

하이브리드 레이저 용접

깊은 용접 레이저용접

레이저 적층 공법

TIG 용접

이종소재 레이저 용접

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.

2023년 8월 7일 update

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

FLOW-3D CAST Suites

FLOW-3D CAST Suites

FLOW-3D CAST v5 comes in Suites of relevant casting processes: 

HIGH PRESSURE DIE CASTING SUITE

Process Workspace

High Pressure Die Casting

Features

Thermal Die Cycling
– Cooling/heating channels
– Spray cooling
Filling
– Shot sleeve with Plunger
– Shot motion
– Ladles, stoppers
– Venting efficiency
– PQ^2 analysis
– HPDC machine database
Solidification
– Squeeze pins
Cooling


PERMANENT MOLD CASTING SUITE

Process Workspaces

Permanent Mold Casting
Low Pressure Die Casting
Tilt Pour Casting

Features

Thermal Die Cycling
– Cooling/heating channels
Filling
– Tilt pouring
Solidification
– Squeeze pins
Cooling


SAND CASTING SUITE

Process Workspaces

Sand Casting
Low Pressure Sand Casting

Features

Filling
– Permeable molds
– Moisture evaporation in molds
– Gas generation in cores
– Ladle model
Solidification
– Exothermic sleeves
– Chills
– Cast iron solidification
Cooling


LOST FOAM CASTING SUITE

Process Workspaces

Lost Foam
Sand Casting
Low Pressure Sand Casting

Features

Filling
– Permeable molds
– Moisture evaporation in molds
– Gas generation in cores
– Ladle model
– Lost foam pattern evaporation models (Fast model and Full model)
– Lost foam defect prediction
Solidification
– Exothermic sleeves
– Chills
– Cast iron solidification
Cooling

 


ALL SUITES INCLUDE THESE CORE FEATURES:

Solver Engine

  • TruVOF – The most accurate filling simulation tool in the industry
  • Heat transfer and solidification
  • Shrinkage – Rapid Shrinkage model and Shrinkage with flow model
  • Temperature dependent properties
  • Multi-block meshing including conforming meshes
  • Turbulence models
  • Non-Newtonian viscosity (shear thinning/thickening, thixotropic)
  • Flow tracers
  • Active Simulation Control with Global Conditions
  • Surface tension model
  • Thermal stress analysis with warpage
  • General moving geometry w/6 DOF

FlowSight

  • Multi-case analysis
  • Porosity analysis tool

Defect Prediction Tools

  • Gas entrainment model
  • Thermal Modulus output
  • Hot Spot identification
  • Micro and macro porosity prediction
  • Surface defect prediction
  • Shrinkage
  • Cavitation and Cavitation Potential
  • Particle models (Inclusion modeling, collapsed bubble tracking)

User Conveniences

  • Process-oriented workspaces
  • Configurable Simulation Monitor
  • Metal and solid material databases
  • Heat transfer database
  • Filter database
  • Remote solving queues
  • Quick Analyze/Display tool

FSR-05-14_moisture drying model [수분/습기 건조 모델]

Introduction
In the manufacture of paper it is necessary to remove all water from the paper before it is rolled up. The majority of water is typically removed by squeezing the paper between large rollers. The remaining moisture can be removed by forcing hot air through the paper to accelerate its evaporation.
Using heated air can be an expensive process so there is interest in investigating optimum arrangements for achieving the fastest and least expensive means of removing the residual water from paper. A prototype arrangement using heated air is shown in the following figure: (그림은 첨부파일 참조)

Both the paper and the fabric backing are porous materials. The support blocks may not be porous. It is expected that the permeability of the fabric and paper will be a function of their water content.
This report describes a software development that allows for a realistic treatment of the drying process in porous media such as that shown in Fig. 1. A description is given of the new model, which has been validated with available data. This data does not cover the entire range of moisture content or airflow rates that are typically encountered in practice. Consequently, it may be found necessary to make some small model adjustments. It is hoped that the formulation of the model, which is based on simple physical principles, will be easy to adjust to fit a larger range of observations.
Before describing the new model, a better perspective of its capabilities can be appreciated by noting some of the ways that it differs from previous work on paper drying. Most importantly, the new model considers the paper as having finite thickness and properties such as moisture content, temperature and vapor concentration that vary through the thickness. Thus, the paper may have dried on the upstream side, but still be completely wet on the opposite side. Another difference is that air and water vapor constitute a two-component gas that is compressible. Compressibility means, for
example, that the gas velocity in the paper must increase in the direction of flow because of the decrease in pressure through the paper (i.e., density and/or temperature must decrease by expansion to give a pressure decrease). Since flow velocity has an important effect on drying rate, compressibility can influence local drying conditions in the paper.

Finally, by computing transient conditions throughout the paper, this model could be used to investigate arbitrary non-uniform initial conditions or paper with a non-uniform thickness and/or porosity distribution.

 

[다운로드]

FSR-05-14_moisture drying model

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.

Microfluidics Bibliography

Microfluidics Bibliography

다음은 Microfluidics Bibliography의 기술 문서 모음입니다.
이 모든 논문은 FLOW-3D  결과를 특징으로  합니다. 미세 유체 공정 및 장치 를 성공적으로 시뮬레이션하기 위해 FLOW-3D 를 사용 하는 방법에 대해 자세히 알아보십시오  .

2023년 8월 7일 Update

64-23   Tihomir Tjankov, Dimitar Trifonov, Conceptual design and 3D modeling of a microfluidic device for liver cells investigation, Industry 4.0, 8.2; pp. 39-41, 2023.

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

64-22   Babatunde Aramide, Computational modelling of electrohydrodynamic jetting (Taylor cone formation, dripping & jet evolution): Case study of electrospinning, Thesis, University College London, 2022.

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

138-21   Enver Guler, Mine Eti, Aydin Cihanoglu, Esra Altiok, Kadriye Ozlem Hamaloglu, Burcu Gokcal, Ali Tuncel, Nalan Kabay, Ion exchange membranes with enhanced antifouling properties to produce energy from renewable sources, Proceedings of the 6th International Symposium on Green and Smart Technologies for a Sustainable Society, Santander, Cantabria, Spain, December 9-10, 2021.

45-21   Navid Tonekaboni, Mahdi Feizbahr, Nima Tonekaboni, Guang-Jun Jiang, Hong-Xia Chen, Optimization of solar CCHP systems with collector enhanced by porous media and nanofluid, Mathematical Problems in Engineering, 2021; 9984940, 2021. doi.org/10.1155/2021/9984840

40-21   B. Hayes, G.L. Whiting, R. MacCurdy, Modeling of contactless bubble–bubble interactions in microchannels with integrated inertial pumps, Physics of Fluids, 33.4; 042002, 2021. doi.org/10.1063/5.0041924

Below is a collection of technical papers in our Microfluidics Bibliography. All of these papers feature FLOW-3D results. Learn more about how FLOW-3D can be used to successfully simulate microfluidic processes and devices.

14-21   Jian-Chiun Liou, Chih-Wei Peng, Philippe Basset, Zhen-Xi Chen, DNA printing integrated multiplexer driver microelectronic mechanical system head (IDMH) and microfluidic flow estimation, Micromachines, 12.1; 25, 2021. doi.org/10.3390/mi12010025

08-20   Li Yong-Qiang, Dong Jun-Yan and Rui Wei, Numerical simulation for capillary driven flow in capsule-type vane tank with clearances under microgravity, Microgravity Science and Technology, 2020. doi.org/10.1007/s12217-019-09773-z

89-19   Tim Dreckmann, Julien Boeuf, Imke-Sonja Ludwig, Jorg Lumkemann, and Jorg Huwyler, Low volume aseptic filling: impact of pump systems on shear stress, European Journal of Pharmeceutics and Biopharmeceutics, in press, 2019. doi:10.1016/j.ejpb.2019.12.006

88-19   V. Amiri Roodan, J. Gomez-Pastora, C. Gonzalez-Fernandez, I.H. Karampelas, E. Bringas, E.P. Furlani, and I. Ortiz, CFD analysis of the generation and manipulation of ferrofluid droplets, TechConnect Briefs, pp. 182-185, 2019. TechConnect World Innovation Conference & Expo, Boston, Massachussetts, USA, June 17-19, 2019.

55-19     Julio Aleman, Sunil K. George, Samuel Herberg, Mahesh Devarasetty, Christopher D. Porada, Aleksander Skardal, and Graça Almeida‐Porada, Deconstructed microfluidic bone marrow on‐a‐chip to study normal and malignant hemopoietic cell–niche interactions, Small, 2019. doi: 10.1002/smll.201902971

37-19     Feng Lin Ng, Miniaturized 3D fibrous scaffold on stereolithography-printed microfluidic perfusion culture, Doctoral Thesis, Nanyang Technological University, Singapore, 2019.

32-19     Jenifer Gómez-Pastora, Ioannis H. Karampelas, Eugenio Bringas, Edward P. Furlani, and Inmaculada Ortiz, Numerical analysis of bead magnetophoresis from flowing blood in a continuous-flow microchannel: Implications to the bead-fluid interactions, Nature: Scientific Reports, Vol. 9, No. 7265, 2019. doi: 10.1038/s41598-019-43827-x

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

75-18   Tobias Ladner, Sebastian Odenwald, Kevin Kerls, Gerald Zieres, Adeline Boillon and Julien Bœuf, CFD supported investigation of shear induced by bottom-mounted magnetic stirrer in monoclonal antibody formulation, Pharmaceutical Research, Vol. 35, 2018. doi: 10.1007/s11095-018-2492-4

53-18   Venoos Amiri Roodan, Jenifer Gómez-Pastora, Aditi Verma, Eugenio Bringas, Inmaculada Ortiz and Edward P. Furlani, Computational analysis of magnetic droplet generation and manipulation in microfluidic devices, Proceedings of the 5th International Conference of Fluid Flow, Heat and Mass Transfer, Niagara Falls, Canada, June 7 – 9, 2018; Paper no. 154, 2018.  doi: 10.11159/ffhmt18.154

35-18   Jenifer Gómez-Pastora, Cristina González Fernández, Marcos Fallanza, Eugenio Bringas and Inmaculada Ortiz, Flow patterns and mass transfer performance of miscible liquid-liquid flows in various microchannels: Numerical and experimental studies, Chemical Engineering Journal, vol. 344, pp. 487-497, 2018. doi: 10.1016/j.cej.2018.03.110

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.

15-18   J. Gómez-Pastora, I.H. Karampelas, A.Q. Alorabi, M.D. Tarn, E. Bringas, A. Iles, V.N. Paunov, N. Pamme, E.P. Furlani, I. Ortiz, CFD analysis and experimental validation of magnetic droplet generation and deflection across multilaminar flow streams, Biotech, Biomaterials and Biomedical TechConnect Briefs, vol. 3, pp. 182-185, 2018.

14-18   J. Gómez-Pastora, C. González-Fernández, I.H. Karampelas, E. Bringas, E.P. Furlani, and I. Ortiz, Design of Magnetic Blood Cleansing Microdevices through Experimentally Validated CFD Modeling, Biotech, Biomaterials and Biomedical TechConnect Briefs, vol. 3, pp. 170-173, 2018.

10-18   A. Gupta, I.H. Karampelas, J. Kitting, Numerical modeling of the formation of dynamically configurable L2 lens in a microchannel, Biotech, Biomaterials and Biomedical TechConnect Briefs, Vol. 3, pp. 186 – 189, 2018.

17-17   I.H. Karampelas, J. Gómez-Pastora, M.J. Cowan, E. Bringas, I. Ortiz and E.P. Furlani, Numerical Analysis of Acoustophoretic Discrete Particle Focusing in Microchannels, Biotech, Biomaterials and Biomedical TechConnect Briefs 2017, Vol. 3

16-17   J. Gómez-Pastora, I.H. Karampelas, E. Bringas, E.P. Furlani and I. Ortiz, CFD analysis of particle magnetophoresis in multiphase continuous-flow bioseparators, Biotech, Biomaterials and Biomedical TechConnect Briefs 2017, Vol. 3

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

102-16   J. Brindha, RA.G. Privita Edwina, P.K. Rajesh and P.Rani, “Influence of rheological properties of protein bio-inks on printability: A simulation and validation study,” Materials Today: Proceedings, vol. 3, no.10, pp. 3285-3295, 2016. doi: 10.1016/j.matpr.2016.10.010

99-16   Ioannis H. Karampelas, Kai Liu, Fatema Alali, and Edward P. Furlani, Plasmonic Nanoframes for Photothermal Energy Conversion, J. Phys. Chem. C, 2016, 120 (13), pp 7256–7264

98-16   Jelena Dinic and Vivek Sharma, Drop formation, pinch-off dynamics and liquid transfer of simple and complex fluidshttp://meetings.aps.org/link/BAPS.2016.MAR.B53.12, APS March Meeting 2016, Volume 61, Number 2, March 14–18, 2016, Baltimore, Maryland

67-16  Vahid Bazargan and Boris Stoeber, Effect of substrate conductivity on the evaporation of small sessile droplets, PHYSICAL REVIEW E 94, 033103 (2016), doi: 10.1103/PhysRevE.94.033103

57-16   Ioannis Karampelas, Computational analysis of pulsed-laser plasmon-enhanced photothermal energy conversion and nanobubble generation in the nanoscale, PhD Dissertation: Department of Chemical and Biological Engineering, University at Buffalo, State University of New York, July 2016

44-16   Takeshi Sawada et al., Prognostic impact of circulating tumor cell detected using a novel fluidic cell microarray chip system in patients with breast cancer, EBioMedicine, Available online 27 July 2016, doi: 10.1016/j.ebiom.2016.07.027.

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

30-16   Ioannis H. Karampelas, Kai Liu and Edward P. Furlani, Plasmonic Nanocages as Photothermal Transducers for Nanobubble Cancer Therapy, Nanotech 2016 Conference & Expo, May 22-25, Washington, DC.

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.

02-16  Stephen D. Hoath (Editor), Fundamentals of Inkjet Printing: The Science of Inkjet and Droplets, ISBN: 978-3-527-33785-9, 472 pages, February 2016 (see chapters 2 and 3 for FLOW-3D results)

125-15   J. Berthier, K.A. Brakke, E.P. Furlani, I.H. Karampelas, V. Poher, D. Gosselin, M. Cubinzolles and P. Pouteau, Whole blood spontaneous capillary flow in narrow V-groove microchannels, Sensors and Actuators B: Chemical, 206, pp. 258-267, 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.

77-15   Ho-Lin Tsai, Weng-Sing Hwang, Jhih-Kai Wang, Wen-Chih Peng and Shin-Hau Chen, Fabrication of Microdots Using Piezoelectric Dispensing Technique for Viscous Fluids, Materials 2015, 8(10), 7006-7016. doi: 10.3390/ma8105355

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

28-15   Yongqiang Li, Mingzhu Hu, Ling Liu, Yin-Yin Su, Li Duan, and Qi Kang, Study of Capillary Driven Flow in an Interior Corner of Rounded Wall Under MicrogravityMicrogravity Science and Technology, June 2015

20-15   Pamela J. Waterman, Diversity in Medical Simulation Applications, Desktop Engineering, May 2015, pp 22-26,

16-15   Saurabh Singh, Ann Junghans, Erik Watkins, Yash Kapoor, Ryan Toomey, and Jaroslaw Majewski, Effects of Fluid Shear Stress on Polyelectrolyte Multilayers by Neutron Scattering Studies, © 2015 American Chemical Society, DOI: 10.1021/acs.langmuir.5b00037, Langmuir 2015, 31, 2870−2878, February 17, 2015

11-15   Cheng-Han Wu and Weng-Sing Hwang, The effect of process condition of the ink-jet printing process on the molten metallic droplet formation through the analysis of fluid propagation direction, Canadian Journal of Physics, 2015. doi: 10.1139/cjp-2014-0259

03-15 Hanchul Cho, Sivasubramanian Somu, Jin Young Lee, Hobin Jeong and Ahmed Busnaina, High-Rate Nanoscale Offset Printing Process Using Directed Assembly and Transfer of Nanomaterials, Adv. Materials, doi: 10.1002/adma.201404769, February 2015

122-14  Albert Chi, Sebastian Curi, Kevin Clayton, David Luciano, Kameron Klauber, Alfredo Alexander-Katz, Sebastián D’hers and Noel M Elman, Rapid Reconstitution Packages (RRPs) implemented by integration of computational fluid dynamics (CFD) and 3D printed microfluidics, Research Gate, doi: 10.1007/s13346-014-0198-7, July 2014

113-14 Cihan Yilmaz, Arif E. Cetin, Georgia Goutzamanidis, Jun Huang, Sivasubramanian Somu, Hatice Altug, Dongguang Wei and Ahmed Busnaina, Three-Dimensional Crystalline and Homogeneous Metallic Nanostructures Using Directed Assembly of Nanoparticles, 10.1021/nn500084g, © 2014 American Chemical Society, April 2014

110-14 Koushik Ponnuru, Jincheng Wu, Preeti Ashok, Emmanuel S. Tzanakakis and Edward P. Furlani, Analysis of Stem Cell Culture Performance in a Microcarrier Bioreactor System, Nanotech, Washington, D.C., June 15-18, 2014

109-14   Ioannis H. Karampelas, Young Hwa Kim and Edward P. Furlani, Numerical Analysis of Laser Induced Photothermal Effects using Colloidal Plasmonic Nanostructures, Nanotech, Washington, D.C., June 15-18, 2014

108-14   Chenxu Liu, Xiaozheng Xue and Edward P. Furlani, Numerical Analysis of Fully-Coupled Particle-Fluid Transport and Free-Flow Magnetophoretic Sorting in Microfluidic Systems, Nanotech, Washington, D.C., June 15-18, 2014

95-14   Cheng-Han Wu, Weng-Sing Hwang, The effect of the echo-time of a bipolar pulse waveform on molten metallic droplet formation by squeeze mode piezoelectric inkjet printing, Accepted November 2014, Microelectronics Reliability (2014) , © 2014 Elsevier Ltd. All rights reserved.

85-14   Sudhir Srivastava, Lattice Boltzmann method for contact line dynamics, ISBN: 978-90-386-3608-5, Copyright © 2014 S. Srivastava

61-14   Chenxu Liu, A Computational Model for Predicting Fully-Coupled Particle-Fluid Dynamics and Self-Assembly for Magnetic Particle Applications, Master’s Thesis: State University of New York at Buffalo, 2014, 75 pages; 1561583, http://gradworks.umi.com/15/61/1561583.html

41-14 Albert Chi, Sebastian Curi, Kevin Clayton, David Luciano, Kameron Klauber, Alfredo Alexander-Katz, Sebastian D’hers, and Noel M. Elman, Rapid Reconstitution Packages (RRPs) implemented by integration of computational fluid dynamics (CFD) and 3D printed microfluidics, Drug Deliv. and Transl. Res., DOI 10.1007/s13346-014-0198-7, # Controlled Release Society 2014. Available for purchase online at SpringerLink.

21-14  Suk-Hee Park, Ung Hyun Koh, Mina Kim, Dong-Yol Yang, Kahp-Yang Suh and Jennifer Hyunjong Shin, Hierarchical multilayer assembly of an ordered nanofibrous scaffold via thermal fusion bonding, Biofabrication 6 (2014) 024107 (10pp), doi:10.1088/1758-5082/6/2/024107, IOP Publishing, 2014. Available for purchase online at IOP.

17-14   Vahid Bazargan, Effect of substrate cooling and droplet shape and composition on the droplet evaporation and the deposition of particles, Ph.D. Thesis: Department of Mechanical Engineering, The University of British Columbia, March 2014, © Vahid Bazargan, 2014

73-13  Oliver G. Harlen, J. Rafael Castrejón-Pita, and Arturo Castrejon-Pita, Asymmetric Detachment from Angled Nozzles Plates in Drop-on Demand Inkjet Printing, NIP & Digital Fabrication Conference, 2013 International Conference on Digital Printing Technologies. Pages 253-549, pp. 277-280(4)

63-13  Fatema Alali, Ioannis H. Karampelas, Young Hwa Kim, and Edward P. Furlani, Photonic and Thermofluidic Analysis of Colloidal Plasmonic Nanorings and Nanotori for Pulsed-Laser Photothermal ApplicationsJ. Phys. Chem. C, Article ASAP, DOI: 10.1021/jp406986y, Copyright © 2013 American Chemical Society, September 2013.

25-13  Sudhir Srivastava, Theo Driessen, Roger Jeurissen, Herma Wijshoff, and Federico Toschi, Lattice Boltzmann Method to Study the Contraction of a Viscous Ligament, International Journal of Modern Physics © World Scientific Publishing Company, May 2013.

11-13  Li-Chieh Hsu, Yong-Jhih Chen, Jia-Huang Liou, Numerical Investigation in the Factors on the Pool Boiling, Applied Mechanics and Materials Vol. 311 (2013) pp 456-461, © (2013) Trans Tech Publications, Switzerland, doi:10.4028/www.scientific.net/AMM.311.456. Available for purchase online at Scientific.Net.

10-13 Pamela J. Waterman, CFD: Shaping the Medical World, Desktop Engineering, April 2013. Full article available online at Desktop Engineering.

90-12 Charles R. Ortloff and Martin Vogel, Spray Cooling Heat Transfer- Test and CFD Analysis, Electronics Cooling, June 2012. Available online at Electronics Cooling.

79-12    Daniel Parsaoran Siregar, Numerical simulation of evaporation and absorption of inkjet printed droplets, Ph.D. Thesis: Technische Universiteit Eindhoven, September 18, 2012, Copyright 2012 by D.P. Siregar, ISBN: 978-90-386-3190-5.

71-12   Jong-hyeon Chang, Kyu-Dong Jung, Eunsung Lee, Minseog Choi, Seungwan Lee, and Woonbae Kim, Varifocal liquid lens based on microelectrofluidic technology, Optics Letters, Vol. 37, Issue 21, pp. 4377-4379 (2012) http://dx.doi.org/10.1364/OL.37.004377

70-12   Jong-hyeon Chang, Kyu-Dong Jung, Eunsung Lee, Minseog Choi, and Seunwan Lee, Microelectrofluidic Iris for Variable ApertureProc. SPIE 8252, MOEMS and Miniaturized Systems XI, 82520O (February 9, 2012); doi:10.1117/12.906587

69-12   Jong-hyeon Chang, Eunsung Lee, Kyu-Dong Jung, Seungwan Lee, Minseog Choi, and  Woonbae Kim, Microelectrofluidic Lens for Variable CurvatureProc. SPIE 8486, Current Developments in Lens Design and Optical Engineering XIII, 84860X (October 11, 2012); doi:10.1117/12.925852.

61-12  Biddut Bhattacharjee, Study of Droplet Splitting in an Electrowetting Based Digital Microfluidic System, Thesis: Doctor of Philosophy in the College of Graduate Studies (Applied Sciences), The University of British Columbia, September 2012, © Biddut Bhattacharjee.

55-12 Hejun Li, Pengyun Wang, Lehua Qi, Hansong Zuo, Songyi Zhong, Xianghui Hou, 3D numerical simulation of successive deposition of uniform molten Al droplets on a moving substrate and experimental validation, Computational Materials Science, Volume 65, December 2012, Pages 291–301. Available for purchase online at SciVerse.

54-12   Edward P. Furlani, Anthony Nunez, Gianmarco Vizzeri, Modeling Fluid Structure-Interactions for Biomechanical Analysis of the Human Eye, Nanotech Conference & Expo, June 18-21, 2012, Santa Clara, CA.

53-12   Xinyun Wu, Richard D. Oleschuk and Natalie M. Cann, Characterization of microstructured fibre emitters in pursuit of improved nano electrospray ionization performance, The Royal Society of Chemistry 2012, http://pubs.rsc.org, DOI: 10.1039/c2an35249d, May 2012

25-12    Edward P. Furlani, Ioannis H. Karampelas and Qian Xie, Analysis of Pulsed Laser Plasmon-assisted Photothermal Heating and Bubble Generation at the Nanoscale, Lab on a Chip, 10.1039/C2LC40495H, Received 01 May 2012, Accepted 07 Jun 2012. First published on the web 13 Jun 2012.

22-12  R.A. Sultanov, D. Guster, Numerical Modeling and Simulations of Pulsatile Human Blood Flow in Different 3D-Geometries, Book chapter #21 in Fluid Dynamics, Computational Modeling and Applications (2012), ISBN: 978-953-51-0052-2, p. 475 [18 pages]. Available online at INTECH.

21-12  Guo-Wei Huang, Tzu-Yi Hung, and Chin-Tai Chen, Design, Simulation, and Verification of Fluidic Light-Guide Chips with Various Geometries of Micro Polymer Channels, NEMS 2012, Kyoto, Japan, March 5-8, 2012. Available for purchase online at IEEE.

103-11   Suk-Hee Park, Development of Three-Dimensional Scaffolds containing Electrospun Nanofibers and their Applications to Tissue Regeneration, Ph.D. Thesis: School of Mechanical, Aersospace and Systems Engineering, Division of Mechanical Engineering, KAIST, 2011.

81-11   Xinyun Wu, Modeling and Characterization of Microfabricated Emitters-In Pursuit of Improved ESI-MS Performance, thesis: Department of Chemistry, Queen’s University, December 2011, Copyright © Xinyun Wu, 2011

79-11  Cong Lu, A Cell Preparation Stage for Automatic Cell Injection, thesis: Graduate Department of Mechanical and Industrial Engineering, University of Toronto, Copyright © Cong Lu, 2011

77-11 Ge Bai, W. Thomas Leach, Computational fluid dynamics (CFD) insights into agitation stress methods in biopharmaceutical development, International Journal of Pharmaceutics, Available online 8 December 2011, ISSN 0378-5173, 10.1016/j.ijpharm.2011.11.044. Available online at SciVerse.

72-11  M.R. Barkhudarov, C.W. Hirt, D. Milano, and G. Wei, Comments on a Comparison of CFD Software for Microfluidic Applications, Flow Science Technical Note #93, FSI-11-TN93, December 2011

45-11  Chang-Wei Kang, Jiak Kwang Tan, Lunsheng Pan, Cheng Yee Low and Ahmed Jaffar, Numerical and experimental investigations of splat geometric characteristics during oblique impact of plasma spraying, Applied Surface Science, In Press, Corrected Proof, Available online 20 July 2011, ISSN 0169-4332, DOI: 10.1016/j.apsusc.2011.06.081. Available to purchase online at SciVers

33-11  Edward P. Furlani, Mark T. Swihart, Natalia Litchinitser, Christopher N. Delametter and Melissa Carter, Modeling Nanoscale Plasmon-assisted Bubble Nucleation and Applications, Nanotech Conference and Expo 2011, Boston, MA, June 13-16, 2011

32-11  Lu, Cong and Mills, James K., Three cell separation design for realizing automatic cell injection, Complex Medical Engineering (CME), 2011 IEEE/ICME, pp: 599 – 603, Harbin, China, 10.1109/ICCME.2011.5876811, June 2011. Available online at IEEEXplore.

25-11 Issam M. Bahadur, James K. Mills, Fluidic vacuum-based biological cell holding device with piezoelectrically induced vibration, Complex Medical Engineering (CME), 2011 IEEE/ICME International Conference on, 22-25 May 2011, pp: 85 – 90, Harbin, China. Available online at: IEEE Xplore.

14-11  Edward P. Furlani, Roshni Biswas, Alexander N. Cartwright and Natalia M. Litchinitser, Antiresonant guiding optofluidic biosensor, doi:10.1016/j.optcom.2011.04.014, Optics Communication, April 2011

05-11 Hyeju Eom and Keun Park, Integrated numerical analysis to evaluate replication characteristics of micro channels in a locally heated mold by selective induction, International Journal of Precision Engineering and Manufacturing, Volume 12, Number 1, 53-60, DOI: 10.1007/s12541-011-0007-x, 2011. Available online at: SpringerLink.

70-10  I.N. Volnov, V.S. Nagornyi, Modeling Processes for Generation of Streams of Monodispersed Fluid Droplets in Electro-inkjet Applications, Science and Technology News, St. Petersburg State Polytechnic University, 4, pp 294-300, 2010. In Russian.

62-10  F. Mobadersani, M. Eskandarzade, S. Azizi and S. Abbasnezhad, Effect of Ambient Pressure on Bubble Growth in Micro-Channel and Its Pumping Effect, ESDA2010-24436, pp. 577-584, doi:10.1115/ESDA2010-24436, ASME 2010 10th Biennial Conference on Engineering Systems Design and Analysis (ESDA2010), Istanbul, Turkey, July 12–14, 2010. Available online at the ASME Digital Library.

58-10 Tsung-Yi Ho, Jun Zeng, and Chakrabarty, K, Digital microfluidic biochips: A vision for functional diversity and more than moore, Computer-Aided Design (ICCAD), 2010 IEEE/ACM International Conference on, DOI: 10.1109/ICCAD.2010.5654199, © IEEE, November 2010. Available online at IEEE Explore.

51-10  Regina Bleul, Marion Ritzi-Lehnert, Julian Höth, Nico Scharpfenecker, Ines Frese, Dominik Düchs, Sabine Brunklaus, Thomas E. Hansen-Hagge, Franz-Josef Meyer-Almes, Klaus S. Drese, Compact, cost-efficient microfluidics-based stopped-flow device, Anal Bioanal Chem, DOI 10.1007/s00216-010-4446-5, Available online at Springer, November 2010

22-10    Krishendu Chakrabarty, Richard B. Fair and Jun Zeng, Design Tools for Digital Microfluidic Biochips Toward Functional Diversification and More than Moore, IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems, Vol. 29, No. 7, July 2010

14-10 E. P. Furlani and M. S. Hanchak, Nonlinear analysis of the deformation and breakup of viscous microjets using the method of lines, International Journal for Numerical Methods in Fluids (2010), © 2010 John Wiley & Sons, Ltd., Published online in Wiley InterScience. DOI: 10.1002/fld.2205

55-09 R.A. Sultanov, and D. Guster, Computer simulations of  pulsatile human blood flow through 3D models of the human aortic arch, vessels of simple geometry and a bifurcated artery, Proceedings of the 31st Annual International Conference of the IEEE EMBS (Engineering in Medicine and Biology Society), Minneapolis, September 2-6, 2009, p.p. 4704-4710.

30-09 Anurag Chandorkar and Shayan Palit, Simulation of Droplet Dynamics and Mixing in Microfluidic Devices using a VOF-Based Method, Sensors & Transducers journal, ISSN 1726-5479 © 2009 by IFSA, Vol.7, Special Issue “MEMS: From Micro Devices to Wireless Systems,” October 2009, pp. 136-149.

13-09 E.P. Furlani, M.C. Carter, Analysis of an Electrostatically Actuated MEMS Drop Ejector, Presented at Nanotech Conference & Expo 2009, Houston, Texas, USA, May 3-7, 2009

12-09 A. Chandorkar, S. Palit, Simulation of Droplet-Based Microfluidics Devices Using a Volume-of-Fluid Approach, Presented at Nanotech Conference & Expo 2009, Houston, Texas, USA, May 3-7, 2009

3-09 Christopher N. Delametter, FLOW-3D Speeds MEMS Inkjet Development, Desktop Engineering, January 2009

42-08  Tien-Li Chang, Jung-Chang Wang, Chun-Chi Chen, Ya-Wei Lee, Ta-Hsin Chou, A non-fluorine mold release agent for Ni stamp in nanoimprint process, Microelectronic Engineering 85 (2008) 1608–1612

26-08 Pamela J. Waterman, First-Pass CFD Analyses – Part 2, Desktop Engineering, November 2008

09-08 M. Ren and H. Wijshoff, Thermal effect on the penetration of an ink droplet onto a porous medium, Proc. Eurotherm2008 MNH, 1 (2008)

04-08 Delametter, Christopher N., MEMS development in less than half the time, Small Times, Online Edition, May 2008

02-08 Renat A. Sultanov, Dennis Guster, Brent Engelbrekt and Richard Blankenbecler, 3D Computer Simulations of Pulsatile Human Blood Flows in Vessels and in the Aortic Arch – Investigation of Non-Newtonian Characteristics of Human Blood, The Journal of Computational Physics, arXiv:0802.2362v1 [physics.comp-ph], February 2008

01-08 Herman Wijshoff, thesis: University of Twente, Structure- and fluid dynamics in piezo inkjet printheads, ISBN 978-90-365-2582-4, Venlo, The Netherlands January 2008.

30-07 A. K. Sen, J. Darabi, and D. R. Knapp, Simulation and parametric study of a novel multi-spray emitter for ESI–MS applications, Microfluidics and Nanofluidics, Volume 3, Number 3, June 2007, pp. 283-298(16)

28-07 Dan Soltman and Vivek Subramanian, Inkjet-Printed Line Morphologies and Temperature Control of the Coffee Ring Effect, Langmuir; 2008; ASAP Web Release Date: 16-Jan-2008; (Research Article) DOI: 10.1021/la7026847

23-07 A K Sen and J Darabi, Droplet ejection performance of a monolithic thermal inkjet print head, Journal of Micromechanical and Microengineering,vol.17, pp.1420-1427 (2007) doi:10.1088/0960-1317/17/8/002; Abstract only.

18-07 Herman Wisjhoff, Better Printheads Via Simulation, Desktop Engineering, October 2007, Vol. 13, Issue 2

17-07 Jos de Jong, Ph.D. Thesis: University of Twente, Air entrapment in piezo inkjet printing, ISBN 978-90-365-2483-4, April 2007

15-07 Krishnendu Chakrabarty and Jun Zeng, (Ed.), Design Automation Methods and Tools for Microfluidics-Based Biochips, Springer, September 2006.

14-07 Fei Su and Jun Zeng, Computer-aided design and test for digital microfluidics, IEEE Design & Test of Computers, 24(1), 2007, 60-70.

13-07 Jun Zeng, Modeling and simulation of electrified droplets and its application to computer-aided design of digital microfluidics, IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems, 25(2), 2006, 224-233.

12-07 Krishnendu Chakrabarty and Jun Zeng, (2005), Automated top-down design for microfluidic biochips, ACM Journal on Emerging Technologies in Computing Systems, 1(3), 2005, 186–223.

01-07 Wijshoff, Herman, Drop formation mechanisms in piezo-acoustic inkjet, NSTI-Nanotech 2007, ISBN 1420061844 Vol. 3, 2007)

23-06 John J. Uebbing, Stephan Hengstler, Dale Schroeder, Shalini Venkatesh, and Rick Haven, Heat and Fluid Flow in an Optical Switch Bubble, Journal of Microelectromechanical Systems, Vol. 15, No. 6, December 2006

21-06 Wijshoff, Herman, Manipulating Drop Formation in Piezo Acoustic Inkjet, Proc. IS&T’s NIP22, 79 (2006)

20-06 J. de Jong, H. Reinten, M. van den Berg, H. Wijshoff, M. Versluis, G. de Bruin, A. Prosperetti and D. Lohse, Air entrapment in piezo-driven inkjet printheads, J. Acoust. Soc. Am. 120(3), 1257 (2006)

11-06 A. K. Sen, J. Darabi, D. R. Knapp and J. Liu, Modeling and Characterization of a Carbon Fiber Emitter for Electrospray Ionization, 1 MEMS and Microsystems Laboratory, Department of Mechanical Engineering, University of South Carolina, 300 Main Street, Columbia, SC 29208, USA, 2 Department of Pharmacology, Medical University of South Carolina, Charleston, SC

5-06 E. P. Furlani, B. G. Price, G. Hawkins, and A. G. Lopez, Thermally Induced Marangoni Instability of Liquid Microjets with Application to Continuous Inkjet Printing, Proceedings of NSTI Nanotech Conference 2006, Vol. 2, pp 534-537.

28-05 O B Fawehinmi, P H Gaskell, P K Jimack, N Kapur, and H M Thompson, A combined experimental and computational fluid dynamics analysis of the dynamics of drop formation, May 2005. DOI: 10.1243/095440605X31788

5-05 E. P. Furlani, Thermal Modulation and Instability of Newtonian Liquid Microjets, presented at Nanotech 2005, Anaheim, CA, May 8-12, 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

19-04 G. F. Yao, Modeling of Electroosmosis Without Resolving Physics Inside a Electric Double Layer, Flow Science Technical Note (FSI-04-TN69)

12-04 Jun Zeng and Tom Korsmeyer, Principles of Droplet Electrohydrodynamics for Lab-on-a-Chip, Lab. Chip. Journal, 2004, 4(4), 265-277

9-04 Constantine N. Anagnostopoulos, James M. Chwalek, Christopher N. Delametter, Gilbert A. Hawkins, David L. Jeanmaire, John A. Lebens, Ali Lopez, and David P. Trauernicht, Micro-Jet Nozzle Array for Precise Droplet Metering and Steering Having Increased Droplet Deflection, Proceedings of the 12th International Conference on Solid State Sensors, Actuators and Microsystems, sponsored by IEEE, Boston, June 8-12, 2003, pp. 368-71

8-04 Christopher N. Delametter, David P. Trauernicht, James M. Chwalek, Novel Microfluidic Jet Deflection – Significant Modeling Challenge with Great Application Potential, Technical Proceedings of the 2002 International Conference on Modeling and Simulation of Microsystems sponsored by NSTI, San Juan, Puerto Rico, April 21-25, 2002, pp. 44-47

6-04 D. Vadillo*, G. Desie**, A Soucemarianadin*, Spreading Behavior of Single and Multiple Drops, *Laboratoire des Ecoulements Geophysiques et Industriels (LEGI), and **AGFA-Gevaert Group N.V., XXI ICTAM, 15-21 August 2004, Warsaw, Poland

2-04 Herman Wijshoff, Free Surface Flow and Acousto-Elastic Interaction in Piezo Inkjet, Nanotech 2004, sponsored by the Nano Science & Technology Institute, Boston, MA, March 2004

30-03 D Souders, I Khan and GF Yao, Alessandro Incognito, and Matteo Corrado, A Numerical Model for Simulation of Combined Electroosmotic and Pressure Driven Flow in Microdevices, 7th International Symposium on Fluid Control, Measurement and Visualization

27-03 Jun Zeng, Daniel Sobek and Tom Korsmeyer, Electro-Hydrodynamic Modeling of Electrospray Ionization – CAD for a µFluidic Device-Mass Spectrometer Interface, Agilent Technologies Inc, paper presented at Transducers 2003, June 03 Boston (note: Reference #10 is to FLOW-3D)

17-03 John Uebbing, Switching Fiber-optic Circuits with Microscopic Bubbles, Sensors Magazine, May 2003, Vol 20, No 5, p 36-42

16-03 CFD Speeds Development of MEMS-based Printing Technology, MicroNano Magazine, June 2003, Vol 8, No 6, p 16

3-03 Simulation Speeds Design of Microfluidic Medical Devices, R&D Magazine, March 2003, pp 18-19

1-03 Simulations Help Microscopic Bubbles Switch Fiber-Optic Circuits, Agilent Technologies, Fiberoptic Product News, January 2003, pp 22-23

27-02 Feng, James Q., A General Fluid Dynamic Analysis of Drop Ejection in Drop-on-Demand Ink Jet Devices, Journal of Imaging Science and Technology®, Volume 46, Number 5, September/October 2002

1-02 Feixia Pan, Joel Kubby, and Jingkuang Chen, Numerical Simulation of Fluid Structure Interaction in a MEMS Diaphragm Drop Ejector, Xerox Wilson Research Center, Institute of Physics Publishing, Journal of Micromechanics and Microengineering, 12 (2002), PII: SO960-1317(02)27439-2, pp. 70-76

48-01   Rainer Gruber, Radial Mass Transfer Enhancement in Bubble-Train Flow, PhD thesis in Engineering Sciences, Rheinisch- Westf alischen Technische Hochschule Aachen, December 2001.

34-01 Furlani, E.P., Delametter, C.N., Chwalek, J.M., and Trauernicht, D., Surface Tension Induced Instability of Viscous Liquid Jets, Fourth International Conference on Modeling and Simulation of Microsystems, April 2001

12-01 C. N. Delametter, Eastman Kodak Company, Micro Resolution, Mechanical Engineering, Col 123/No 7, July 2001, pp 70-72

11-01 C. N. Delametter, Eastman Kodak Company, Surface Tension Induced Instability of Viscous Liquid Jets, Technical Proceeding of the Fourth International Conference on Modeling and Simulation of Microsystems, April 2001

9-01 Aman Khan, Unipath Limited Research and Development, Effects of Reynolds Number on Surface Rolling in Small Drops, PVP-Col 431, Emerging Technologies for Fluids, Structures and Fluids, Structures and Fluid Structure Interaction — 2001

2-00 Narayan V. Deshpande, Significance of Inertance and Resistance in Fluidics of Thermal Ink-Jet Transducers, Journal of Imaging Science and Technology, Volume 40, Number 5, Sept./Oct. 1996, pp.457-461

4-98 D. Deitz, Connecting the Dots with CFD, Mechanical Engineering Magazine, pp. 90-91, March 1998

14-94 M. P. O’Hare, N. V. Deshpande, and D. J. Drake, Drop Generation Processes in TIJ Printheads, Xerox Corporation, Adv. Imaging Business Unit, IS&T’s Tenth International Congress on Advances in Non-Impact Printing, Tech. 1994

14-92 Asai, A.,Three-Dimensional Calculation of Bubble Growth and Drop Ejection in a Bubble Jet Printer, Journal of Fluids Engineering Vol. 114 December 1992:638-641

Contact Line Insights

Contact Line Insights

FLOW-3D의 수치 모델링 기능은 코팅 성능 향상에 관심이 있는 엔지니어에게 이상적입니다. 계산 시뮬레이션은 코팅 흐름에 영향을 미치는 다양한 물리적 공정의 상대적 중요성과 효과를 연구하는 훌륭한 방법입니다. 물리적 테스트에서 프로세스를 분리하거나 해당 프로세스의 규모를 임의로 조정하는 것이 항상 가능한 것은 아닙니다. 이 섹션에서는 리 블릿 형성(rivulet formation), 핑거링(fingering), 증발, 거친 표면 위의 접촉선 이동 및 유체 흡수와 관련하여 FLOW-3D의 정적 및 동적 접촉각 처리에 대해 설명합니다.

Static and Dynamic Contact Angles

FLOW-3D는 입력으로 설정된 정적 접촉각의 함수로 동적 접촉각과 자유 표면 인터페이스에서 작용하는 관련 힘을 정확하게 계산하여 유체의 소수성을 캡처 할 수 있습니다. 아래 시뮬레이션은 물방울이 경사면 아래로 이동함에 따라 정적 접촉각이 동적 접촉각에 미치는 영향을 보여줍니다.

L.M. Hocking 박사는 그의 저서 [“A moving fluid interface on a rough surface,” J. Fluid Mech., 76, 801, (1976)]에서 표면에 미세한 요철이 흐름 구조를 유도하기 때문에 Contact line이 고체 표면을 통해 이동할 수 있으며 이는 거시적 관점에서 “velocity slip”로 해석 될 수 있다고 했습니다.

이 가설에 대한 전산 해석은 FLOW-3D를 이용하여 쉽게 수행됩니다. 선택된 테스트는 가로, 규칙적으로 이격 된 직사각형 슬롯 패턴 이차원 고체 표면 구성됩니다. 슬롯은 2mm 깊이 10mm 폭, 그리고 그들 사이 폭 10mm 고체 조각을 갖고 이격 됩니다. 이 크기는 전형적으로 상대적으로 부드러운 표면에 긁힌 모양입니다. 액체와 고체 사이의 정적인 접촉각이 60 °가 되도록 선택 하였습니다. 작동 유체는 물로 선정되었고 시험은 채널을 통해 속도30cm / s의 평균 물높이 15mm의 채널의 바닥에 있는 거친 표면을 두고 구동 이루어져 있습니다. 채널의 상단은 free-slip boundary로 정해집니다.

Hocking의 주장대로 micro-scale 교란이 Large scale 관점에서 보았을 때 계산된 속도장으로 보면 velocity slip의 한 종류로서 해석 될 수 있습니다. 아래는 계산된 수평 속도 분포를 나타내고 있습니다. 이것은 표면 바로 위에 제어 볼륨 층의 계산 된 수평 속도 분포를 제공하는 X-Y 플롯에 그래픽으로 보여 주고 있습니다. 격자 미세화에 의해 표면의 고체 부분의 윗쪽 속도가 영이 되는 경향이 있지만, 슬롯들 위에 있는 속도는 영이 안되게 유지됩니다. 많은 요철 위의 이러한 속도의 평균은 효과적인 슬립으로 해석 될 수 있는 non-zero 수평 이송 속도를 일으킵니다.

Evaporative Effects

분산된 고체 물질을 포함하는 액체 방울이 고체 표면에서 건조되면 고체 물질이 침전물로 남습니다. 이 퇴적물의 패턴은 많은 인쇄, 청소 및 코팅 공정에 중요한 의미를 갖습니다. 한 가지 유형의 침전물의 전형적인 예는 왼쪽 이미지와 같이 유출 된 커피 조각의 둘레를 따라 링 얼룩이 형성되는 “커피 링”문제입니다. 이러한 유형의 링 침전물은 액체의 증발로 인한 표면 장력 구동 흐름의 결과로 발생하며, 특히 방울 주변에서 발생합니다 [1].

Drying

건조는 코팅 공정의 중요한 부분입니다. 잘 도포된 코팅은 건조 결함으로 인해 완전히 손상될 수 있습니다. 건조 중에 온도 및 용질 구배는 밀도 및 표면 장력 구배로 인해 코팅 내 흐름을 유도 할 수 있으며, 이로 인해 잠재적으로 코팅 품질이 손상 될 수 있습니다. FLOW-3D의 증발 잔류물 모델을 통해 사용자는 건조로 인한 흐름을 시뮬레이션하고 값 비싼 물리적 실험에 소요되는 시간을 줄일 수 있습니다.

FLOW-3D’s evaporation residue model simulates a 3D view of residue formed from toluene after drying (magnified 30x)

Modeling Ring Formation

FLOW-3D는 증발이 가장 큰 접촉 라인에서의 증착으로 인해 에지 고정이 발생 함을 보여줍니다.

링 형성 모델링
증발에 의해 접촉 라인에서 생성 된 흐름 시뮬레이션
증발은 증발로 인한 열 손실로 인해 액체를 냉각시킵니다 (색상은 온도를 나타냄). 동시에 고체 표면은 전도에 의해 액체를 가열합니다. 증발은 접촉 라인 근처에서 가장 크므로 액체가 접촉 라인을 향해 흐르게하여 정적 상태를 다시 설정합니다. 최종 결과는 액체가 완전히 증발하는 액체 가장자리에 부유 고체가 증착됩니다.

FLOW-3D의 접촉 선 고정 모델에 대해 자세히 알아보십시오.

Simulation of flow generated at a contact line by evaporation

Dip Coating

Dip Coating

딥 코팅은 코팅 재료가 들어있는 탱크에 기판을 담그고 탱크에서 조각을 제거하여 배수하는 것입니다. 이와 같은 일시적인 코팅 문제는 고정 메쉬 내에서 유체의 움직임이 결정되기 때문에 FLOW-3D를 사용하여 간단하고 효율적으로 해결할 수 있습니다 (메쉬를 따르는 유체의 움직임이 아님). 

이 3D 시뮬레이션은 증발이 수반되는 딥 코팅 공정을 보여줍니다. 습식 필름은 용액에서 작은 개별 기판을 제거하여 증착됩니다. 모델은 추가적으로 용매의 증발을 설명합니다. 이는 필름 증착 중에 증발이 유체 역학과 겹치는 휘발성 용매의 경우와 관련이 있습니다. 잔류 물 모델은 코팅 된 건조 필름의 프로파일을 계산하는 고유 한 기능을 제공합니다. “가장자리 효과”의 정확한 평가를 통해 엔지니어는 최종 박막 형상 및 균질성에 대한 공정 매개 변수 또는 유체 특성의 영향을 분석 할 수 있습니다.

Dr. Julien Boeuf of Roche Diagnostics GmbH. 제공.

딥 코팅 공정에 대한 프레젠테이션은 Roche Diagnostics GmbH의 Julien Boeuf 박사의 2013 Conference Proceedings, “Model of dip coating with concomitant evaporation,“에서 확인할 수 있습니다.

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

MEMS/WELD 분야

Microfluidics

Microfluidics는 집적 회로 산업에서 사용되는 것과 유사한 공정을 사용하여 소형 기기의 제조에 급격하게 성장하는 기술입니다. Microfluidics 기술은 0.1 미크론에서 1mm에 이르기까지 매우 작은 장치로 기계, 유체, 광학, 전자 기능을 통합 할 수있는 방법을 제공합니다. Microfluidics는 기존의 방법과 비교하면 두 가지 중요한 장점이 있습니다. 첫째, 대량으로 제조 될 수 있으므로, 생산의 비용이 실질적으로 감소 될 수 있습니다. 둘째, 집적 회로에 통합 될 수 있어서 다른 기술보다 훨씬 더 복잡한 시스템으로 제조 될 수 있습니다.

Chip packaging simulation. Results generated by FLOW-3D/MP, FLOW-3D‘s HPC solution.

엔지니어 및 과학자가 설계, 시험 제작하고 그 성능을 최적화하기 위해 장치를 재 설계하는 등, 다른 제조 방법에서와 같이 microfluidics 설계 프로세스는 매우 고가 일 수 있습니다. 그러나, 수치 시뮬레이션은 전자, 기계, 화학, 열 과학 및 유체 과학 등의 분야에 걸쳐 정량 분석과 중요한 통찰력을 제공 할 수 있습니다.

laser-sintering

 

코팅분야

Coating

FLOW-3D는 산업계 및 학계의 코팅 연구원들이 기계 설계 연구, Display 공정개발 및 최적화를 위해 사용했습니다. 미크론 규모의 코팅 물리학을 이해하는 것은 코팅 유체 유변학의 복잡한 특성과 기판 및 Die와의 상호 작용으로 인해 어려울 수 있습니다.

FLOW-3D 는 비용이 많이 드는 실제 실험에 의존하지 않고, 코팅 프로세스를 분석할 수 있는 편리한 방법을 제공합니다. FLOW-3D는 표면 장력, Wall 접착, 용액 운반, 밀도 기반 흐름 및 상 변화의 영향을 이해하기위한 고밀도 모델링을 제공합니다.

Forward roll coating 공정에 대한 FLOW-3D의 시뮬레이션은 high capillary number수로 인한ribbing 결함을 포착합니다. 이 모델은 backing rollers가 400 micron nip을 통해 유체를 끌어 당길 때 표면 장력과 점도의 효과를 통합합니다. 시뮬레이션은 Lee, et al [1]의 연구를 기반으로합니다.

ribbing 시작에 대한 정확한 예측을 통해 엔지니어는 결함을 방지하기 위한 공정 매개 변수를 식별하고 수정할 수 있습니다.

Reference

[1] Lee, J. H., Han, S. K., Lee, J. S., Jung, H. W., & Hyun, J. C. (2010). Ribbing instability in rigid and deformable forward roll coating flows. Korea Australia Rheology Journal, 22(1), 75-80.

Bibliography

Models

Conference Proceedings


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