Topology‐porosity assessment of TPMS ‐based aluminum foams for accelerated melting of RT31 phase change material

Thermal energy storage systems based on phase change materials are limited by the low thermal conductivity of PCMs, which results in slow melting and temperature non‐uniformity. In this study, a three‐dimensional numerical investigation was performed to assess the combined effects of TPMS ( Triply Periodic Minimal Surface ) topology and porosity on the melting behavior of RT31 PCM. Gyroid, Schwarz Diamond, and Schwarz Primitive structures were examined using the enthalpy‐porosity method in ANSYS Fluent R19. The numerical model showed good agreement with the experimental RT31 data, with an RMSE of 1.24°C and an of 0.995. At the common porosity of 85.11%, the Gyroid configuration reached 95% melting in 57.29 s, compared with 100.89 s for Schwarz Diamond and 99.91 s for Schwarz Primitive, corresponding to reductions of 43.2% and 42.7%, respectively. For the Gyroid topology, decreasing porosity from 92.03% to 78.18% reduced the time to 95% melting from 65.76 to 50.32 s, an improvement of approximately 23.5%. However, lower porosity also reduced PCM volume and restricted natural convection. The results therefore show that intermediate Gyroid porosities provide the most balanced compromise between rapid melting, thermal uniformity, natural‐convection development, and latent storage capacity.