Heat exchanger design and thermal-fluid coupling simulation based on triply periodic minimal surfaces (TPMS)

Heat exchangers, as critical thermal exchange equipment, are widely used in fields such as aerospace and energy chemical engineering. However, the design of traditional heat exchangers is often constrained by structural design and manufacturing processes. The triply periodic minimal surfaces (TPMS), an advanced porous structure derived from nature with mathematically definable properties, offers a novel solution to overcome these limitations when integrated with additive manufacturing (AM). This study employs a parametric design methodology based on TPMS structures to systematically construct a series of heat exchanger models. These models utilize Gyroid, Diamond, and Schwarz as unit cells with varying unit cell dimensions and wall thicknesses. Through thermal-fluid coupling simulations, the effect of key geometric parameters on the macroscopic performance of the heat exchangers is investigated. The results indicate that TPMS structures can effectively enhance heat transfer performance. Smaller unit cell dimensions contribute to intensified heat transfer, with the temperature difference between hot and cold fluids under optimal conditions reduced to 8.74% of the initial temperature difference. Variations in unit cell wall thickness have a minor impact on the performance of the heat exchangers studied here once steady state is achieved. Among the different TPMS configurations, the Diamond unit cell demonstrates superior heat transfer performance due to its multi-branch flow channel structure. This study provides a theoretical foundation and design reference for the development of high-performance heat exchangers based on TPMS structures and additive manufacturing.