Study on convective heat transfer performance of triply periodic minimal surface structures based on multi-aspect ratio regulation

Triply periodic minimal surfaces (TPMS) possess excellent convective heat transfer performance, making them highly promising for thermal management in hypersonic vehicles. In this study, a series of novel Diamond structures (TPMS1–TPMS5) were constructed by adjusting the longitudinal aspect ratio (AR) and were experimentally tested and numerically compared with Gyroid, IWP (Infinite Wrapped Package), and the classic Diamond model. The results show that, due to its higher specific surface area, the Diamond structure exhibits significantly better overall heat dissipation performance than the Gyroid and IWP structures. By optimizing the aspect ratio difference (Tx), TPMS1–TPMS4 achieved comprehensive heat transfer performance (j/f) that was 44.3%–53.6%, 16.5%–34.2%, 23.4%–44.1%, and 34.5%–60.1% higher, respectively, than the classic Diamond structure. Furthermore, hybrid structures TPMSH (Hybrid triply periodic minimal surface) and TPMSF (Fusion triply periodic minimal surface) were designed using a Sigmoid function, combining the advantages of low flow resistance (TPMS1) and high heat exchange (TPMS4). Compared with TPMS1 and TPMS4, the j/f of the TPMSH model increased by 14.4%–32.4% and 15.6%–27.8%, respectively, while the segmented hybrid TPMSF model was significantly affected by flow regime, showing limitations in coupling flow and heat transfer under different flow conditions. This study provides a theoretical basis for the application of TPMS structures in the thermal management of aircraft surfaces under extreme environments and offers a technical foundation for meeting the thermal protection engineering requirements of various operating conditions.