The Performance Investigation And Structure Optimization Of New LED Heat Sink Of Heat Pipe

In recent years, while" green lighting " has been developed rapidly, lightingdevices have been regard as the key development areas in our country. Then LED(LightEmitting Diode) is been called as the star of environmental protection and energysaving lighting, which is going to be regarded as development trend in the future. Heatdissipation is important to lifetime of LED, with the increasing of power, the lower heatdissipation is the main technical bottleneck for the development of high power lightemitting diode in modern time.In this thesis, the new heat sink of heat pipe has been designed to solve thisproblem and the performance of heat transfer and flow is investigated for the new heatsink of heat pipe by ANSYS ICEPAK software. At the same test conditions, heatdissipation performance of the new heat sink of heat pipe is compared with traditionalaluminum finned heat sink and copper finned heat sink. Then the structure of the newheat sink of heat pipe is optimized to improve the heat dissipation performance, whichis analyzed by temperature field and velocity field. The junction temperature of chipsand thermal resistance of different structures of new heat sinks of heat pipe areinvestigated to find variation with the heat power.The results show that (1) the junction temperature of chips and thermal resistanceof the new heat sink of heat pipe are lowest in three types of heat sinks, which ambienttemperature is25℃and surface area of heat sink is0.03818㎡.(2) The structure of thenew heat sink of heat pipe is optimized, then it is found that the junction temperature ofchips and thermal resistance of P-type new heat sink of heat pipe are lowest in differentkinds of heat sinks of heat pipe, so heat dissipation performance of it is best.(3)The finsheight and fins spacing of P-type new heat sink of heat pipe are analyzed andinvestigated for heat dissipation performance. Under the condition of the same finsheight, with the change of fins spacing, there is a minimum of the junction temperatureand thermal resistance, then it is found that this minimum can move to the increase offins spacing with the increase of fins height.(4)Un-uniform fins height of the P-typenew heat sink of heat pipe is designed. Under the condition of the same volume, it isfound that it can make the junction temperature of chips and thermal resistance decrease significantly and improve heat dissipation performance effectively for heat sink of heatpipe, which the fins height in the outside of it is increased and the fins height in themiddle of it is decreased.