Turbulent Natural Convection Inside U-shaped Enclosure

Abstract

The turbulent buoyancy induced flow and heat transfer characteristics inside U-shaped enclosure has been numerically documented. Fully elliptic Navier-Stockes and energy equations are solved using control volume based finite volume method with a staggered grid arrangements. A computer program using SIMPLEC algorithm is developed to handle the problem of interest. The effect of Rayleigh number and aspect ratio on the studied parameters are examined. The problem is simulated for Ra up to 1016 and aspect ratio of (0.25, 0.35 and 0.5). The k-є model is engaged with the flow equations to model the turbulence while the wall function method is used to model the regions near the walls. The present results show that the aspect ratio and Ra have a significant effect on the flow and thermal characteristics. The rate of heat transfer is increased with the decrease of aspect ratio and increase with Ra. A multi cellular flow has been obtained at decreasing the aspect ratio for Ra up to 1012.