Convection Heat Transfer and Performance Analysis of a Triply Periodic Minimal Surface (TPMS) for a Novel Heat Exchanger

Heat exchangers are necessary in most engineering systems that move thermal energy from a hot source to a colder location. The development of additive manufacturing technology facilitates the design and optimization of heat exchangers by introducing triply periodic minimal surface (TPMS) structures. TPMSs have shown excellent mechanical and thermal performance, which can improve heat energy transfer efficiency in heat exchangers. This current study intends to design and develop efficient, lightweight heat exchangers for aerospace and space applications. Using the TPMS structure, a porous construction encloses a horizontal tube that circulates heated fluid. Low-temperature water circulates inside a rectangular box that houses the complete system to remove heat from the horizontal pipe. Three porous structures, the gyroid, diamond, and FKS structures, were employed and examined. Porous models with various porosities and surface areas (15 cm2 and 24 cm2) were investigated. The results revealed that the gyroid structure exhibits the highest Nusselt number for heat removal (Nu max = 2250), confirming the highest heat transfer and lowest pressure drop among the three structures under investigation. The maximum Nusselt number obtained for the FKS structure is less than 1000, whereas, for the diamond structure, it is near 1250. A linear variation in the average Nusselt number as a function of the structure surface area was found for the FKS and diamond structures. In contrast, nonlinearity was observed in the gyroid structures.