Double-diffusive mixed convection in the slot ventilated enclosure with different arrangements of supplying air flow ports

Abstract

Steady double-diffusive mixed convection in an enclosure with side venting and discrete heat and contaminant sources is numerically studied under supplying upside and returning downside (STRB) mode and returning upside and supplying downside mode (RTSB), respectively. The parameters governing the fluid flow include the Grashof number Gr (10 2 –10 6 ), Reynolds number Re (100–500), supplying or returning distance H 1 / H T (0–2), Prandtl number Pr (0.7), buoyancy ratio N , and Schmidt number Sc . Effects of Gr, Re , and H 1 / H T on the flow patterns, thermal, and species transports were numerically investigated concerning STRB and RTSB modes. Fluid flow, heat, and species transports in the enclosure are visualized and analyzed by the contours of stream function, heat function, and mass function, respectively. Air age was also presented to evaluate the freshness of the enclosed fluid. Averaged Nusselt number of the heat source and Sherwood number of the contaminant source are power-law correlated with Gr, Re , and H 1 / H T for two ventilation modes, respectively. The correlations demonstrate that the ratio of averaged Nusselt number to Sherwood number was approximately approaching unity, independent of ventilation modes and values of H 1 / H T . This investigation could benefit the future design of room ventilation and thermal removals from the electronic chips.