Enhancement of heat transfer in cooling channels for electronic devices using multi-directional graded triply periodic minimal surfaces (TPMS)

The use of liquid cooling in thermal management systems has expanded due to the increased heat generation from integrated electronic devices and manufacturing processes. The triply periodic minimal surface (TPMS) structure has garnered attention due to its superior mechanical properties while utilizing less material. This study numerically analyzed and compared heat transfer characteristics of liquid cooling TPMS with those of conventional straight channels at various inlet Reynolds numbers (Re) ranging from 737 to 5110. Additionally, this study examined the effects of multi-directional porosity gradings and TPMS materials in diamond channels to enhance their heat transfer performance. The total convective heat transfer coefficient (HTC) of the diamond channels was on average 118.8 % higher than that of conventional straight channels. Y(-20 %)Z(-10 %) channel with a diamond structure, which features 20 % and 10 % decreases in porosity along the cross-sectional (Y) and flow (Z) directions, respectively, exhibited a 22.6 % lower standard deviation in working surface temperature than the uniform TPMS channel due to locally enhanced convective HTC and low conductive thermal resistance. Across all Re numbers, the Y(-20 %)Z(-10 %) channel with copper demonstrated the lowest total thermal resistance owing to copper's higher thermal conductivity and optimized porosity grading.