Experimental And Theoretical Investigation On Performance Of Heat Pipe Spreader

Nowadays the thermal losses of power electronic devices like CPU are increasing. At the same time, their sizes are decreasing. Consequently heat sinks have to dissipate very large heat flux. Therefore the thermal environment is a main issue in their performance and reliability. Meanwhile, the heat flux are not uniformly distributed in the CPU, the points which have large heat flux are called "hot spots". How to eliminate the "hot spots"becomes a great challenge and also arouse much interests among the researches. In order to improve heat transfers, materials with high thermal conductivity like diamonds seem very interesting. But as we know they are very expensive and not practical when the costs are taken into account. In this paper we propose a kind of novel thermal spreader to replace them with flat heat pipes. Firstly the background and significance of flat heat pipes are briefly introduced, as well as the history in this field .Secondly the theoretical study is described to instruct the work pursued in this paper. Thirdly an experimental study is described in order to show the performance of flat heat pipes used as thermal spreader in power electronics cooling. Finally thermal simulation of the ideal thermal spreader is provided to evaluate the thermal spreader with heat pipe. Thanks to them, thermal spreaders made with heat pipes and thermal spreaders made with copper are compared. When the input power is 100W, a temperature drop of 18.7℃of maximal temperature is reached when the heat-pipe spreader was added to the bottom of the sink.