Numerical study of single-channel heat exchangers reconstructed from TPMS structures

Triply periodic minimal surface (TPMS) structures are attractive for compact heat exchangers because of their large specific surface area and complex flow topology. However, their two naturally separated continuous subdomains are generally more suitable for multi-port or dual-channel configurations than for applications requiring a single inlet and a single outlet. This study proposes a class of single-channel heat exchangers reconstructed from TPMS geometries. The two original TPMS subdomains were connected to form a continuous single-inlet-single-outlet flow path. Two representative TPMS topologies, namely Gyroid and Diamond, were reconstructed and evaluated. The effects of eight solid volume fractions (10%–80%) and six inlet flow rates (0.1–2.5 m 3 /h) on convective flow and heat transfer were investigated, and the results were compared with those of a conventional parallel-channel heat exchanger. The results showed that the reconstructed TPMS structures achieved up to 25% higher convective heat transfer than the baseline heat exchanger under low-flow conditions. The results also indicate that the thermal-hydraulic trade-off can be regulated by adjusting the inlet flow rate and solid volume fraction. The results clarify the topology-dependent trade-off between heat transfer enhancement and hydraulic penalty in single-channel TPMS heat exchangers and provide guidance for the design of compact TPMS-based heat exchangers with single-inlet-single-outlet configurations.