Turbulent regime of thermogravitational convection in a closed cavity

We have performed a numerical analysis of the nonstationary turbulent natural convection in a closed region with heat-conducting walls of finite thickness and a heat source located at the cavity base under the conditions of convective-radiative heat exchange with the environment. Typical distributions of the thermohydrodynamic parameters (streamlines, temperature field, field of the kinetic energy of turbulence, and dissipation field of the kinetic energy of turbulence) in a fairly wide range of Grashof numbers 107 ≤ Gr ≤ 109 have been obtained. Results characterizing the scales of influence of the nonstationarity factor and the relative heat conductivity coefficient of the material of the surrounding walls on the heat transfer intensity are presented. A correlation for determining the average Nusselt number on the heat source surface has been established. © 2010 Springer Science+Business Media, Inc.