A chemical-potential multiphase lattice Boltzmann model with high Reynolds and Weber numbers

Abstract

Numerical simulation of nonideal fluids is one of the most successful applications of the lattice Boltzmann method. The Chapman–Enskog (C–E) analysis reveals that the pressure tensor in the chemical-potential lattice Boltzmann model deviates from the standard one, and consequently, the surface tension cannot be effectively adjusted by the coefficient. In this paper, an additional term is constructed to modify the pressure tensor, while a scaling factor is utilized to prevent the expansion of the phase interface. The proposed model has thermodynamic consistency and is able to linearly adjust the surface tension without changing the interface width largely. Laplace's law and Galilean invariance are also verified. The present model has excellent dynamic stability at large liquid/gas density ratios and, thus, enables dynamic simulations with high Reynolds and Weber numbers.