A novel gyroid-based two-inlet heat sink for enhancing heat dissipation and mitigating hot spots in power electronics cooling

Localized thermal hotspots can create steep temperature gradients within microprocessors, significantly reducing their performance and accelerating failure. This study presents a numerical investigation of a novel two-inlet heat sink (TIHS) incorporating a gyroid triply periodic minimal surface (TPMS) structure to mitigate such hotspots. The heat sink features two inlets and two outlets, with the outlets positioned diagonally opposite to the inlets. The TIHS consists of two independent flow channels that exchange heat through the TPMS walls. To replicate realistic thermal loading conditions, three non-uniform heating schemes—with five, three, and two randomly distributed hotspots—were applied to the bottom surface of the heat sink. The two-inlet configuration significantly reduced hotspot intensity and improved temperature uniformity at the outlet, because of convoluted flow paths and the large heat transfer surface area provided by the TPMS structure. Key thermal performance indicators such as maximum temperature rise, mean temperature deviation, and thermal resistance all decreased with increasing flow rate, indicating enhanced heat dissipation, although this required slightly higher pumping power. The temperature gradient along the streamwise direction indicated efficient bidirectional heat transfer between the fluid and solid regions of the TPMS structure. The heat sink maintained a uniform temperature gradient beyond a certain height, with only minor non-uniformities in localized zones, commonly referred to as “dead zones” within the TPMS. Compared to a non-TPMS model, the two-inlet gyroid-based heat sink dissipated up to 40 times more heat. These results underscore the potential of this design for efficient thermal management in power electronic systems.