Study of Flow and Heat Transfer Characteristics in Asymmetrically Heated Sintered Porous Heat Sinks With Periodical Baffles

Abstract

This work numerically examined the mechanism of heat transfer in a sintered porous heat sink with baffles. A channel filled with the sintered porous heat sink was asymmetrically heated and metallic baffles were periodically mounted on the heated surface. The fluid medium was air. The results indicate that no recirculation occurred between baffles. The metallic baffle obtained heat from the heated surface by conduction directly from the heated surface and indirectly through the porous media. It dissipated heat to the fluid that passed over the zone above the baffle. The Nusselt numbers in the cases with baffles exceeded those in cases without a baffle. The enhancement in the average Nusselt numbers of sintered porous heat sinks with baffles increased as the Reynolds number (Re) declined; the baffle height (h∕H) increased; the baffle length (w∕H) increased, or the baffle pitch (XL) decreased. However, at Re=500, the average Nusselt number in the case with h∕H=0.3 was higher than those with h∕H=0.7, 0.5, and 0.1. Additionally, the minimum enhancement appeared at around Re=3000 for various h∕H, w∕H, and XL. For the cases with h∕H⩽0.3 and various w∕H as well as XL, at Re>3000, sintered porous heat sinks with baffles insignificantly improved heat transfer.