Turbulent thermal convection at high Rayleigh numbers for a Boussinesq fluid of constant Prandtl number

Abstract

The results from direct numerical simulations of turbulent Boussinesq convection are briefly presented. The flow is computed for a cylindrical cell of aspect ratio 1∕2 in order to compare with the results from recent experiments. The results span eight decades of Ra from 2×106 to 2×1014 and form the baseline data for a strictly Boussinesq fluid of constant Prandtl number (Pr=0.7). A conclusion is that the Nusselt number varies nearly as the 1∕3 power of Ra for about four decades towards the upper end of the Ra range covered.