Comparative study of different multilayered PCM finned heat sinks using low melting point alloys and paraffin: A numerical analysis

Growing need for high-performance electronic devices has necessitate effective heat management solutions. This study conducts a three-dimensional numerical analysis of phase change material (PCM)-based heat sinks, examining single, double, and triple-layered structures with and without internal fins. The heat sinks are subjected to heat fluxes of 30,000 W/m² and 100,000 W/m² applied from both the bottom and side directions. The analysis evaluates the thermal performance of low-melting-point alloy (LMPA) PCM and paraffin-based PCM with comparable melting temperatures, while maintaining a constant PCM volume fraction (100 %) and under a set point temperature (SPT) of 100 °C. A cascading approach in the triple-layered module, where PCM layers are arranged in decreasing melting temperatures along the heat flux direction, is introduced. The results show that the cascaded PCM configuration in three layers are more effective to slow down the base temperature increase of the heat sink than the single and double ones. The presence of fins with triple layered LMPA PCM module shows a superior base temperature reduction, the complete melting time reach to about 1113 s under the temperature of 95.26 °C, remaining well below the SPT of 100 °C. This demonstrates the capability of LMPAs to sustain lower temperatures for extended periods, outperforming paraffin in terms of thermal shock resistance and faster melting under high heat flux. This work advances the design of PCM-based heat sinks by integrating cascaded configurations, metal PCM, and high-conductivity fins, offering an innovative holistic analysis of their combined effects on performance and providing a viable solution for cooling high-power electronic devices.