Numerical Study Of Air Convection In Two-dimensional Square Cavity

To meet the requirement of indoor environment control, pollutant dispersion, heat and wetdissipation of equipment, this paper makes the basic research work on the air convection intwo-dimensional square cavity.First of all, this paper researches calculation method of convective heat transfer andcompares average Nusselt number with the benchmark solution. The error is within1.00%,which verifies the correctness of the method. Different processing method of density, thermalconductivity, dynamic viscosity, specific heat, gas property have influence on the calculationresults. The error is within1.50%when temperature difference is below30K and the maximumerror is9.30%when temperature difference is500K by Boussinesq. The maximum error ofconstant property is7.28%when temperature difference is500K. Gas property changed withtemperature can not be ignored.Secondly, the article researches the problem of heat and mass transfer with discreteheat/pollutant sources by general combined temperature scale and discusses the effect ofbuoyancy ratio, spacing and the heat source intensity on the flow structure.At last, the problem of air convection with high Rayleigh number is analyzed. Calculationmethod of laminar should be used with Gr<109and turbulence should be used with Gr>109.