Mixed convection over a heated horizontal surface in a partial enclosure

Abstract

Abstract This paper reports a numerical study of mixed convection on a heated horizontal surface within a partially open vertical enclosure in which the buoyancy driven and the forced flows oppose each other. Two values of the Grashof number, 10 4 and 10 5 , are considered. Two kinds of analyses are performed: One in which the domain is considered to be symmetric by the imposition of appropriate symmetry conditions, and the other in which the full domain is simulated. For Gr=10 4 , both the symmetric and the full domains give rise to identical solutions and no multiple steady states are obtained. For Gr=10 5 , multiple steady state solutions arise with both the symmetric domain and the full domains. However, the hysteresis effect observed while using symmetric domain is not observed with the full domain. Further, the full domain analysis reveals interesting asymmetries that have been observed experimentally in a similar configuration in the past. The effect of the location of the exit boundary is also investigated. Results indicate that unless proper exit conditions are chosen, the quantitative results can vary considerably.