Liquid-vapor phase separation under shear by a pseudopotential lattice Boltzmann method

Abstract In this paper, the liquid-vapor phase separation under viscous shear is investigated by using a pseudopotential central moment lattice Boltzmann method. Physically, the multiphase shear flow is governed by two competing mechanisms: surface tension and shear force. It is interesting to find that the liquid tends to form a droplet when the surface tension dominates under conditions of low temperature, shear velocity, and viscosity, and in larger domain size. Otherwise, the liquid tends to form a band if shear force dominates. Moreover, the average density gradient is used as a physical criterion to distinguish the spinodal decomposition and domain growth. Both spatial and temporal changes of density are studied during the phase separation under shear.