A new hybrid lattice-Boltzmann method for thermal flow simulations in low-Mach number approximation

A new low-Mach algorithm for the thermal lattice Boltzmann method (LBM) is proposed aiming at reducing computational cost of flow simulations in low Mach number limit. The well-known approximation adopted to accelerate by enlarging time step through re-scaling psuedoacoustic speed same order fluid motion velocity. This specific process inspired similarity between artificial compressibility and isothermal LBM further extended its counterpart. It must be emphasized that such acceleration strategy a general form, thus can easily applied other compressible LB methods. present overcomes drawback classical pressure gradient scaling due changing. validated various well-documented academic test cases laminar [one dimensional gravity column, 2D (two dimensional) rising bubble, differentially heated square cavity] turbulent [3D (three Taylor–Green vortex 3D cylinder] regimes. All results show excellent agreement with reference data high efficiency.