Computational and experimental analysis of a novel triply periodic minimal surface heat sink with phase change material

The rapid miniaturization of modern electronics has led to significant overheating issues, which pose substantial risks to their performance, reliability, and service life. This study aims to address these challenges by proposing a novel heat sink design incorporating Triply Periodic Minimal Surface (TPMS)-based metal lattice structures embedded with a phase change material (PCM). A comprehensive numerical and experimental investigation was conducted on a 3D-printed PCM metal-lattice heat sink. By employing a three-dimensional unsteady numerical approach and the finite volume method, this study evaluated the metal lattice as a thermal conductivity enhancer. A parametric study was performed to assess the impacts of the heater power input, material, design, and applied heat flux direction. The tested materials were Stainless Steel (SS) and titanium (Ti), with paraffin wax as the PCM. The findings demonstrated that the TPMS-based lattice structure (P3) helps improve the heat exchange between the metal and PCM by facilitating gradual and uniform melting within the system. The SS (P3) heat sink showed up to a 9 % reduction in base temperature compared to Ti (P3) under heater power inputs ranging from 5.1 W to 8.6 W, attributed to its better thermal conductivity. The parametric analysis indicated that, when compared to radial fin design (P5) under multidirectional heat input, P5 returns 3 to 4 °C lower base temperature than P3 for SS and Ti under base-only heating case scenario. On the contrary, P3 outperformed P5 by maintaining side walls 6 to 8 °C cooler during side-only heating. However, the combined effect of base and side heating was found to be insignificant for both designs. The analysis concluded that although the radial fin design (P5) performs slightly better under base-only heating conditions, the TPMS design (P3) would otherwise outperform it, particularly in applications involving multi-directional heat input.