Experimental analysis of flow and heat transfer in a miniature porous heat sink for high heat flux application

Abstract

A novel miniature porous heat sink system was presented for dissipating high heat fluxes of electronic device, and its operational principle and characteristics were analyzed. The flow and heat transfer of miniature porous heat sink was experimentally investigated at high heat fluxes. It was observed that the heat load of up to 280W (heat flux of 140W/cm2) was removed by the heat sink with the coolant pressure drop of about 34kPa across the heat sink system and the heater junction temperature of 62.9°C at the coolant flow rate of 6.2cm3/s. Nu number of heat sink increased with the increase of Re number, and maximum value of 323 for Nu was achieved at highest Re of 518. The overall heat transfer coefficient of heat sink increased with the increase of coolant flow rate and heat load, and the maximal heat transfer coefficient was 36.8kW(m2°C)−1 in the experiment. The minimum value of 0.16°C/W for the whole thermal resistance of heat sink was achieved at flow rate of 6.2cm3/s, and increasing coolant flow rate and heat fluxes could lead to the decrease in thermal resistance. The micro heat sink has good performance for electronics cooling at high heat fluxes, and it can improve the reliability and lifetime of electronic device.