Equilibrium distribution boundary condition in lattice Boltzmann model and numerical simulation of Darcy-Forcheimer drag for fluid flow across a square cylinder array

This article presents a boundary condition for the equilibrium distribution suitable for a variety of non-slip flow Llattice Boltzmann simulations. The boundary condition is based on the Bounce-back method and satisfies mass and momentum conservation principles. The computational results show that the new boundary condition for the equilibrium distribution overcame the erroneous slip velocities resulted from the conventional bounce-back method. The porous flow field around prism-shaped particles which is governed by Darcy-Forcheimer formula is calculated and compared with Lee and Yang's (1997) the predictions are found to be sufficiently reliable.