Lattice Bhatnagar-Gross-Krook Simulations of Turbulent Natural Convection in a Cavity

A thermal lattice Bhatnagar-Gross-Krook (LBGK) model with a robust boundary scheme is developed for the Boussinesq incompressible fluids. In the model the velocity and temperature fields are solved by two independent LBGK equations which are combined into a coupled one for the whole system. The two-dimensional natural convection flow of air in a differentially heated cavity of aspect ratio 4 is simulated for the Rayleigh number up to 10¹⁰. The numerical results are found to be in good agreement with those of previous studies.