Experimental and numerical analysis of porous metal foam effect on heat sink under impingement flow

Abstract

The rise in power density and the shrinking size of electronic components have made efficient thermal management an essential aspect of design. Present study uniquely explores the thermal and hydraulic performance of three different heat sink designs: plate-fin, porous metal foam, and hybrid of finned metal foam, using both experimental and numerical methods under the same impingement cooling conditions. The innovation of this study is its thorough evaluation of these designs using the Local Thermal Non-Equilibrium (LTNE) method to precisely simulate heat transfer within porous materials. Key metrics such as Nusselt number, and pressure drop were assessed. The findings reveal that both porous and hybrid heat sinks surpass the traditional plate-fin design, with the hybrid model showing the highest thermal efficiency due to its larger effective surface area and improved flow disruption. Experimental results indicate that utilizing a hybrid heat sink and metal foam at an input power of 30 W increases the average Nusselt number by 35.82 % and 24.79 %, respectively, compared to the plate-fin heat sink, which, according to the numerical results, these values are 34.76 % and 20.65 %, respectively. These results provide valuable insights for designing advanced thermal management systems for compact electronic devices. The Figure of Merit (FOM) is determined by simultaneously considering both thermal and hydraulic performance. the average FOM for the hybrid and metal foam heat sinks increases by 32.62 % and 19.47 %, respectively, relative to the plate-fin configuration. An increase in the Nusselt number and enhancement of the FOM in heat sinks lead to improved heat transfer efficiency and better protection of electronic components against thermal stress. The effects of input power, interfacial area density, and interfacial heat transfer coefficient are also examined.