Experimental analysis of strut and TPMS-based heat sinks for thermoelectric cooling applications

In this study, the thermodynamic performance of strut-based Simple Cubic (SC) and Body Centered Cubic (BCC) and Triply Periodic Minimal Surface (TPMS)-based gyroid and diamond lattice heat sinks at 60%, 70%, and 80% porosities was experimentally investigated to improve the hot surface thermal management of thermoelectric cooler (TEC). Heat sinks fabricated from AlSi10Mg alloy using Selective Laser Melting (SLM) were tested on a commercial TEC1-12706 module under the same operating conditions. Cold and hot surface temperatures, cooling capacity, heat removal, thermal resistance, and Coefficient of Performance (COP) were evaluated as a function of the applied current. Infrared (IR) thermal camera images are also presented to better understand the heat transfer mechanism at the hot surface. The results reveal that cell topology and porosity are decisive parameters in the thermodynamic performance of the TEC system. Consequently, the average actual COP values obtained with the lattice configurations were 0.7-1.8, which is consistent with the average range of 0.5-1.2 reported in experimental TEC studies conducted with conventional finned heat sinks. It was also observed that structures with highest porosity exhibited the lowest thermodynamic performance in all topologies, which is explained by the fact that the weakening of the conduction channels with increasing porosity outweighs the benefit provided by the increase in specific surface area. These findings demonstrate that lattice-structured heat sinks have significant potential for increasing energy efficiency in TEC systems.