Thermo-hydraulic performance of uniform and hybrid Triply Periodic Minimal Surfaces (TPMS) heat exchangers

Abstract

Triply Periodic Minimal Surfaces (TPMS) geometries are remarkable solutions for achieving optimal heat transfer performance in industries where space-efficient cooling solutions are required. Utilizing these additively manufactured geometries in Heat Exchanger (HX) applications involves a trade-off between maximizing heat transfer and minimizing pressure drop. While prior studies mostly focused on uniform TPMS-based HXs, this research investigates the thermo-hydraulic performance of both uniform (Gyroid, Diamond D, and FRD) and hybrid (Gyroid-FRD, Diamond D-Gyroid, and Diamond D-FRD) TPMS-based HXs. In this study, TPMS geometries were generated via LattGen, and design setup and Computational Fluid Dynamics (CFD) simulation were conducted using Ansys Fluent 2023 R2. All geometries were generated at 30% relative density, and hybrid transitions were achieved via the Sigmoid function. A k-epsilon turbulence model was employed for CFD analysis, and the model was validated against existing literature. Results illustrate that the FRD HX exhibits the best temperature change performance, corresponding to a 13.9 [K] increase in temperature, while introducing a 239.58 [Pa] pressure drop. Among hybrids, Diamond D-FRD HX enabled 13.82 [K] temperature change, improving base uniform FRD flow resistance by 62.5%. The investigation reveals that hybridization can yield an intermediate of thermo-hydraulic performance characteristics from their uniform base structures.