TY - JOUR
T1 - Simulating liquid droplets
T2 - A quantitative assessment of lattice Boltzmann and Volume of Fluid methods
AU - Mukherjee, Siddhartha
AU - Zarghami, Ahad
AU - Haringa, Cees
AU - van As, Kevin
AU - Kenjereš, Saša
AU - Van den Akker, Harry E.A.
N1 - Publisher Copyright:
© 2017 Elsevier Inc.
PY - 2018/4
Y1 - 2018/4
N2 - While various multiphase flow simulation techniques have found acceptance as predictive tools for processes involving immiscible fluids, none of them can be considered universally applicable. Focusing on accurate simulation of liquid-liquid emulsions at the scale of droplets, we present a comparative assessment of the single-component multiphase pseudopotential lattice Boltzmann method (PP-LB, classical and modified) and the Volume of Fluid method (VOF, classical and modified), highlighting particular strengths and weaknesses of these techniques. We show that a modified LB model produces spurious velocities 1–3 orders of magnitude lower than all VOF models tested, and find that LB is roughly 10 times faster in computation time, while VOF is more versatile. Simulating falling liquid droplets, a realistic problem, we find that despite identical setups, results can vary with the technique in certain flow regimes. At lower Reynolds numbers, all methods agree reasonably well with experimental values. At higher Reynolds numbers, all methods underpredict the droplet Reynolds number, while being in good agreement with each other. Particular issues regarding LB simulations at low density ratio are emphasized. Finally, we conclude with the applicability of VOF vis-à-vis PP-LB for a general range of multiphase flow problems relevant to myriad applications.
AB - While various multiphase flow simulation techniques have found acceptance as predictive tools for processes involving immiscible fluids, none of them can be considered universally applicable. Focusing on accurate simulation of liquid-liquid emulsions at the scale of droplets, we present a comparative assessment of the single-component multiphase pseudopotential lattice Boltzmann method (PP-LB, classical and modified) and the Volume of Fluid method (VOF, classical and modified), highlighting particular strengths and weaknesses of these techniques. We show that a modified LB model produces spurious velocities 1–3 orders of magnitude lower than all VOF models tested, and find that LB is roughly 10 times faster in computation time, while VOF is more versatile. Simulating falling liquid droplets, a realistic problem, we find that despite identical setups, results can vary with the technique in certain flow regimes. At lower Reynolds numbers, all methods agree reasonably well with experimental values. At higher Reynolds numbers, all methods underpredict the droplet Reynolds number, while being in good agreement with each other. Particular issues regarding LB simulations at low density ratio are emphasized. Finally, we conclude with the applicability of VOF vis-à-vis PP-LB for a general range of multiphase flow problems relevant to myriad applications.
KW - Emulsions
KW - Liquid droplets
KW - Multiphase flows
KW - Pseudopotential Lattice Boltzmann
KW - Volume of fluid
UR - http://www.scopus.com/inward/record.url?scp=85041503897&partnerID=8YFLogxK
U2 - 10.1016/j.ijheatfluidflow.2017.12.001
DO - 10.1016/j.ijheatfluidflow.2017.12.001
M3 - Article
AN - SCOPUS:85041503897
SN - 0142-727X
VL - 70
SP - 59
EP - 78
JO - International Journal of Heat and Fluid Flow
JF - International Journal of Heat and Fluid Flow
ER -