A coupled lattice Boltzmann and finite volume method for natural convection simulation

A coupled lattice Boltzmann and finite volume method is proposed to solve natural convection in a differentially heated squared enclosure. The computational domain is divided into two subdomains and a message passing zone is between them. The velocity and temperature fields are respectively solved using D2Q9 and D2Q5 models in lattice Boltzmann method (LBM) while SIMPLE algorithm is applied to the finite volume method (FVM). The velocity and temperature information transfers are fulfilled by a nonequilibrium extrapolation scheme. Pure FVM, pure LBM, and the coupled method with two different geometric settings are applied to solve the natural convection with different Rayleigh numbers. The results obtained from the coupled method agreed with those from pure FVM and LBM very well.