Hybrid design of triply periodic minimal surface (TPMS) structures for loop heat pipe wicks to enhance heat and mass transfer

Triply Periodic Minimal Surface (TPMS) structures provide promising applications for loop heat pipe wicks due to their advantages in fluid flow and heat transfer. This study conducted a numerical study on the performance of nine typical TPMS network wick structures. The permeability and flow characteristics of different lattice cell sizes and layers were analyzed. The differences in liquid absorption rates and heat transfer coefficients between different structures were investigated. A novel structure fusion method was proposed to integrate two advantageous TPMS structures, thereby improving overall performance. Results indicate that lattice cell size and number of layers affect the permeability and Darcy number of TPMS structures. The structures with minimal flow area variations along the size direction exhibited rapid absorption rates, while the increase in lattice cell size (10 μm to 50 μm) reduced the absorption rate by 4.94 times. The G Prime structure maintained the highest heat transfer coefficient under various conditions due to its uniform channel cross-section. The G-G P structures fusing Gyroid's flow and G Prime's thermal characteristics were compared across fusion coefficients α. The structure with α=2 shows balanced performance. When α increased to 4 and 6, although the average heat transfer coefficients improved by 5.21 % and 5.63 %, the permeability decreased by 13.65 % and 14.94 %, and pressure drops increased by 28.52 % and 30.99 %. This study may provide new perspectives on high-performance wick design.