Collaborative topology optimization method for two-type triply periodic minimal surfaces (TPMS) heat exchanger

Different types of triply periodic minimal surfaces (TPMS) exhibit distinct heat transfer and flow characteristics. Combining them may yield complementary performance benefits, yet previous studies have focused only on optimizing single-type TPMS. To address this, we propose a collaborative topology optimization method for hybrid structures incorporating both I-graph-wrapped package (IWP) and F-rhombic dodecahedron (F-RD) types. A major contribution is the development and validation of an effective porous media model for F-RD TPMS. Using the effective models of both types, we establish a material interpolation model and a topology optimization formulation aimed at minimizing average temperature under pressure drop constraints. The optimized hybrid TPMS structure significantly outperforms the original single-type design, reducing peak temperature by 35.5 °C, pressure drop by 38.08 %, and material usage by 17 %. It also surpasses the optimized IWP-only design, further reducing peak temperature by 8.23 °C and material consumption by 17 %. These results demonstrate that the proposed framework enables effective multi-type TPMS optimization, simultaneously enhancing thermal performance and enabling lightweight heat exchanger designs.