Analysis of non-physical slip velocity in lattice Boltzmann simulations using the bounce-back scheme

Abstract

In this work, we investigate the non-physical velocity-slip at a solid wall associated with lattice Boltzmann simulations using the bounce-back boundary scheme. By comparing the analytical solutions for the force-driven Poiseuille flow problem of two lattice models involving four and nine discrete velocities respectively, we found that the bounce-back scheme fails to define the behavior of certain discrete velocities and gives room for other factors to generate the commonly observed non-physical velocity-slip. To eliminate this deficiency, it is necessary to supplement the missing definition. For a lid-driven cavity flow, this is shown to be very simple although further study is necessary for more complex geometries.