Effects of metal foam on exergy and entropy of nanofluids in a heat sink applied for thermal management of electronic components
Cong Qi, Tiantian Chen, Jianglin Tu, Yuying Yan
Abstract
To solve the high heat dissipation of the heat sink, a set of experimental device for the flow and heat transfer of the nanofluids through a heat sink filled with metal foam was established in this paper. The impacts of metal foam with diverse pore densities (PPI = 20, 30, 40), nanoparticle mass fractions (from β = 0.0 wt% to β = 0.5 wt%) and Reynolds numbers (Re = 414-1119) on the flow and heat transfer characteristics were investigated. In addition, the thermal and hydraulic properties were evaluated by the exergy efficiency and entropy generation. The conclusions displayed that the metal foam with a pore density (PPI = 40) is instrumental in strengthening the heat transfer under a certain porosity, and the heat sink under the working condition (β = 0.3 wt% and PPI = 40) possesses the best capacity of thermal performance. Nanofluids and metal foam (PPI = 40) can improve Nusselt number by 6.13% and 3.2% at most compared with water and metal foam (PPI = 20 and PPI = 30), respectively. Nanofluids with β = 0.3 wt% exhibit the highest exergy efficiency, and the metal foam with PPI = 40 shows the smallest entropy generation.