A Comprehensive Analysis of Triply Periodic Minimal Surface Structures Applied to Additively Manufactured Conformal Heat Exchangers for High-Speed Applications

The rapid evolution of aerospace technology has introduced a growing demand for efficient thermal management systems, particularly in military aircraft and unmanned aerial systems. Heat exchangers play a pivotal role in dissipating excess heat generated by advanced avionics, propulsion systems, and high-power payloads. Conventional heat exchangers, typically composed of stacked tubes and plates, while effective, present limitations in terms of weight, size, and susceptibility to mechanical failure. In recent years, advanced manufacturing techniques, such as additive manufacturing (AM), have opened new possibilities for designing and producing heat exchangers with complex geometries that traditional manufacturing methods could not achieve. A particularly promising approach involves the use of Triply Periodic Minimal Surfaces (TPMS), which offer enhanced surface area-to-volume ratios and improved thermal transfer efficiency. This work aimed to experimentally and computationally evaluate additively manufactured conformal heat exchangers with the TPMS structure for their heat transfer efficiency, pressure drop, and overall feasibility. A comparison of two conformal TPMS AM heat exchangers was performed, each with a different infill period density, with the goal to optimize the heat exchanger by balancing the pressure loss and heat transfer obtained. Data collected was then compared to the CFD models for validation. The results showed that the effectiveness and heat transfer increased approximately 7% and 4 kW respectively when the cell arc count doubled between both HX’s. The relationship between the Nusselt, Reynolds, and Prandtl number was then presented, along with the effectiveness-NTU relationship between both HX’s. The results of this work enhance the overall understanding of how these novel heat exchangers perform compared to their traditional counterparts and if the technology is ready for implementation into advanced air platforms.