Thermal performance of phase change material (PCM) based pin-finned heat sinks for electronics devices: Effect of pin thickness and PCM volume fraction

•Inclusion of paraffin wax reduces the base temperature of heat sink.•An enhancement ratio of 2.64 at ψ=1.00 is achieved for a SPT of 60°C at 3.174kW/m2 for 2mm thick pin-fin heat sink.•At heat input of 1.98kW/m2, it took 145min and 229min to reach SPTs of 60°C and 70°C respectively.•3mm Pin-fin thick heat sink outperform the 2mm pin-fin thick heat sink for volume fractions of ψ=0.33 and ψ=0.66.•An enhancement of 4.30 is achieved against heat flux of 3.174kW/m2 for 2mm thick pin-fin heat sink. The present experimental investigation focuses on the passive cooling of electronic devices by using phase change material (PCM) based pin-fin heat sinks to increase reliability, to ensure sufficiently lower temperature, to stretch the operating duration and to improve the functionality of installed features. Paraffin wax is used as a PCM and filled in heat sinks made of aluminum. As the thermal conductivity of PCM is very low, aluminum square fins are used as thermal conductivity enhancer (TCE). A volume fraction of TCE is kept constant at 9% and the uniform heat flux is applied to finned and un-finned heat sinks. An un-finned heat sink is used for base line comparison. Fin thicknesses of TCE of 1mm,2mm, and 3mm with square cross sectional area are investigated with a constant height of 20mm. Volume fractions of PCM are varied as 0.00, 0.33, 0.66 and 1.00 for each heat sink to determine the thermal performance. The present study reports thermal performance at various heat fluxes to enhance the operating time for different set point temperatures (SPTs) and to compare the latent heat phase duration for various heat sinks tested. The results reveal that maximum thermal performance in operating time is achieved for 2mm thick pin-fin heat sink filled with PCM volumetric fraction of 1.00.