Research On The Microchannel Heat Dissipation System Of High Power LED Street Lamp

As green lighting,light-emitting diode(LED)which has a series of performance advantages compared with traditional light source,but the heat dissipation problem has been restricting the development of LED industry.Compared with traditional natural convection,forced convection,thermoelectric cooling,microchannel heat dissipation technology which has the advantages of stable structure and high reliability.This paper aims to develop a microchannel radiator.The maximum temperature of simplified heat block of the 90 W high power LED array dropped to below 85? where the ambient temperature is 25? with a large space under the natural convection conditions.This article combines theoretical analysis with experimental analysis,simulation analysis method to optimize the structure of the microchannel heat sink.Firstly,the thermal resistance of the whole LED is theoretically analyzed through the thermal resistance network.Since the heat source and heat sink in this paper have different area and cause diffusion thermal resistance,this paper focuses on analyzing the thermal resistance of diffusion;Second,the self-developed temperature measurement system includes hardware(PC,data acquisition card,thermocouple)software(labview temperature measurement program)to test the thermal performance of the micro-channel;Finally through the Fluent simulation of micro-channel heat sink,and measured Compare and analyze the influencing factors orthogonally and determine the optimal solution.Main conclusions are presented as follows:(1)The microchannel radiator has better heat dissipation performance than a conventional radiator,and can reduce the heat source temperature to 82.44?.Because of the internal heat transfer working medium,it can reach a steady state more quickly;the overall temperature of the microchannel radiator does not appear.Excessive fluctuations indicate that the overall stability is good.Through the study of thermal resistance,it has been found that the thermal resistance of convection heatexchangers accounts for the largest proportion.(2)Due to the complex structure of the microchannel radiators and more features,so we simplified and assumed the microchannel before the simulation.Compared with the results obtained through Fluent simulation which are close to the measured results,so the simplification and assumption are feasible.(3)Through theoretical analysis,there are mainly four factors that affect the heat dissipation performance of the microchannel heat sink,namely,the shape of the microchannel honeycomb,the depth of the microchannel,the distance between adjacent cells,the radius of the circumcircle,and the orthogonal test analysis of these four factors.Orthogonal experiment results in the best combination,and the maximum temperature of the heat source dropped to 77?.