A central-moment multiple-relaxation-time collision model

Abstract

We propose a multiple relaxation time Boltzmann equation collision model by systematically assigning a separate relaxation time to each of the central moments of the distribution function. The Chapman-Enskog calculation leads to correct hydrodynamic equations. The thermal diffusion and viscous dissipation are mutually independent and Galilean invariant. By transforming the central moments into the absolute reference frame and evaluating using fixed discrete velocities, an efficient lattice Boltzmann (LB) model is obtained. The LB model is found to have excellent numerical stability in high-Reynolds numbers simulations.