An extrapolation-based boundary treatment for using the lattice Boltzmann method to simulate fluid-particle interaction near a wall

Abstract

Two important issues need to be addressed when using lattice Boltzmann methods to simulate particulate flows: complex moving boundaries and near contact of two solid objects. This study introduces a new boundary treatment method for using lattice Boltzmann methods to study fluid-particle interaction problems in which solid objects are close to a wall or two solid objects are near contact. The new method does not need to use any additional lubrication correction to total hydrodynamic force, instead implementing the no-slip boundary condition by introducing an appropriate fictitious flow field outside the fluid domain. The new method was verified by simulating a spherical particle falling down in fluids with and without rebound. It is concluded that the proposed boundary treatment method can accurately simulate the fluid-particle interaction near a rigid wall and collision in fluid.