Experimental investigations of thermal resistance of a heat sink with horizontal embedded heat pipes

Abstract

This article experimentally investigates the thermal resistance of a heat sink with horizontal embedded heat pipes. Heat sink with embedded heat pipes disperses heat from CPU to both the base plate and the heat pipes, and then removes heat from fins to the surrounding. This experimental approach measures the thermal resistances of interface between CPU and base plate, base plate, CPU to heat pipes, heat pipes and fins through the thermal resistance analysis. It can be divided into two steps. The first step is to measure the thermal performance of a heat pipe and the next step is the measurement for the thermal performance of heat sink with and without the function of heat pipes. These results are limited to the case of sink-processor assemblies installed horizontally and two U-shaped embedded heat pipes inserted into the heat sink in the paper. The results show that two heat pipes embedded in the base plate carry 36% of the total dissipated heat from CPU, while 64% of heat is delivered from the base plate to the fins. Furthermore, when the CPU power is 140 W, the total thermal resistance is at its minimum 0.27 °C/W and the thermal resistances of CPU to heat pipes and heat pipes are 0.32 °C/W and 0.12 °C/W respectively.