Comparative study of the flow in a differentially heated cavity using thermal lattice Boltzmann method

摘要

A D2Q9 thermal lattice Boltzmann model is applied to investigate the flow in a differentially heated cavity. The paper is intended to analysis the physics of heat and mass transfer in a closure cavity filled with air. For three Rayleigh numbers (Ra = 10~4～10~6), the aspect ratio K are varied from 1 to 10. Results of validation indicate this algorithm is reliable and easy for implementation. It can be found that the circulation rate of heat driven flow get lower when the K get higher. Also, the Nusselt number Nu tends to be approximated to 1 when K is higher than a critical value, which is depended on the value of Ra.