Investigation on the flow and heat transfer of a novel three-fluid heat exchanger based on TPMS

To reduce the number of heat exchangers (HEs) in thermal management systems and minimize the interactions between them, this study performs topology optimization based on the TPMS equation to design a three-fluid HE. Furthermore, fins are incorporated into the three-fluid HE. The influence mechanisms of the TPMS structure, solid volume fraction (Sv) and fin on the flow and heat transfer performance of the three-fluid HE are revealed. Results show that: (1) The three-fluid HE enables efficient heat exchange between each flow channel and air, maintaining high consistency in air temperature and velocity. (2) Compared to Gyroid heat exchanger (G-HE), Diamond heat exchanger (D-HE) exhibits a significantly higher heat transfer coefficient. The heat transfer coefficient of D-HE is approximately 3.1 times that of G-HE. (3) Increasing the Sv enhances the heat transfer performance of the HE, while also increasing flow resistance. When the Sv increases from 7 % to 13 %, the Nu and f on the cold side of the D-HE increase by 34 % and 19.6 %, respectively, while those for the G-HE increase by 13.2 % and 5.9 %. The three-fluid HE enhances the integration of the thermal management system and plays a crucial role in improving the reliability and stability of the system. © 2024 Elsevier Ltd