International Communications in Heat and Mass Transfer, vol.162, 2025 (SCI-Expanded)
This study basically aims to enhance the heat removal performance of conventional solid cylindrical pin-finned heat sinks while maintaining a tolerable pressure drop by inserting porous aluminum material into the slots at the fin tips. To this end, the influences of fin arrangement, fin type, slot width and height, pore density of the open-cell aluminum foam material and convergent/divergent slot design on the thermal and fluid flow characteristic of the air-cooled heat sink equipped with slotted solid cylindrical pin-fins with aluminum foam insert, referred to as a compound finned heat sink were numerically examined within the range of Re = 500–3500 using the COMSOL Multiphysics. Additionally, the thermo-hydraulic performance of integrated heat sink produced by embedding cylindrical solid fins into the bulk porous material was compared with the performance of solid cylindrical, slotted solid cylindrical and compound finned heat sinks. Before the numerical study, a compound finned heat sink was fabricated to validate the simulation results. Its pressure drop and heat removal performances were experimentally tested within the range of Re = 3000 to 15,000. For all the heat sinks examined, an increase in Re resulted in an increase in both the Nusselt number and pressure drop along the flow direction. When it is compared to the solid cylindrical finned heat sink, thermal performance factor (η) of the slotted solid cylindrical and compound finned heat sinks increased by 28 %, and 54 %, respectively. The results also indicated that the compound finned heat sink performs better in terms of η compared to the integrated heat sink within a specific range of Re. For the compound finned heat sink, increasing the slot height and thickness had a positive impact on the Nusselt number, pressure drop and η. However, increasing the pore density of the aluminum foam insert did not produce a similar effect. Finally, the influences of slot geometries (convergent-divergent) on overall performance of investigated heat sinks was found to be insignificant.