Experimental investigation of hexagonal topology-optimized heat sinks for dual-source high-power electronics

A hexagonal topological heat sink was designed using a variable-density topology optimization method, accounting for dual heat sources and the thermal conduction of the external shell. The optimization aimed to minimize the maximum temperature, achieving efficient heat transfer and stable temperature control while avoiding local overheating. The design addresses the complex structural and multi-heat-source requirements of airborne high-power cooling applications. The heat sink was integrally fabricated via selective laser melting and experimentally compared with copper foam, honeycomb, and lattice heat sinks. A structural performance index incorporating mass was introduced to reduce the influence of weight differences on performance evaluation. Results show that the topological structure exhibits excellent temperature control under all conditions, especially at higher heat flux and lower temperature targets. Under the design condition, it improved the temperature control time by 70.21%, 155.32%, and 15.38% compared with copper foam, honeycomb, and lattice heat sinks, respectively. Even accounting for mass differences, the topological fins maintain a significant lightweight advantage, with an average dimensionless structural effectiveness index over 25.00% higher than other structures. Moreover, it achieves superior temperature uniformity, reducing the average inter-chip temperature difference by more than 11.51%. This study confirms the strong potential of three-dimensional topology optimization for chip thermal management and provides guidance for high-power electronic cooling applications.