Thermal Simulation Of Power LED Array And Optimization Of Heat Dissipation Structure

An LED,a light emitting diode,is a semiconductor device that directly converts electrical energy into light energy.LED devices occupy an important position in the lighting market as a green solid-state light source.As people's demand for high-power LED lamps increases,power requirements for LED lamps increase and packaging technology requirements increase.Because a large amount of heat concentration leads to a rapid rise in the junction temperature,the increase in the junction temperature leads to the attenuation of the LED lifetime and the reduction of the light extraction efficiency.Therefore,designing an effective heat dissipation model and using high thermal conductivity materials are particularly important.In recent years,there have been many studies on the selection of LED lamp package structures and thermal interface materials.Graphene materials have attracted attention because of their excellent thermal conductivity in two-dimensional planes.In order to improve the heat dissipation of high-power LEDs,the role of the graphene material in thermal diffusion was fully utilized,and it was combined with the surface of the aluminum radiator substrate.A single high-power LED model and multiple array high-power LED models were experimentally designed.Mainly explored two aspects:(1)The effect of the addition of graphene on the cooling effect of the LED;(2)The influence of different graphene thickness and different graphene shapes on the heat dissipation performance of the LED;because the graphene used in the simulation is very thin,The requirements for meshing are very strict,so mainstream cooling simulation software ANSYS Icepak is used.The experimental simulation results show that: graphene has obvious effect on improving LED heat dissipation,and can generally reduce the junction temperature by about 15° C.to achieve the effect of eliminating hot spots and lowering the junction temperature.At the nanometer thickness level,graphene thickness and shape improve the heat dissipation of the LED.The difference is not significant,and it is almost negligible within the error range.The application of aluminum radiators in the field of LED heat dissipation is the most extensive,thanks to its advantages of easy processing and molding,low density and so on.Inorder to explore the influence of heat sink structure parameters on the heat dissipation performance of LED,this paper designs the best heat sink structure parameters and establishes a model of high power LED street light.The test adopts the control variable method and uses the thermal simulation software Flotherm with its own optimized design function.Explored the aluminum radiator base thickness,fin height,fin thickness,fin spacing four parameters of the LED street junction temperature,pin temperature,light bar and the maximum temperature of the radiator,the experimental simulation results found that the cooling of the LED The degree of influence decreases in accordance with the fin height,fin thickness,fin spacing,and base thickness.Through simulation and analysis,the best heat sink structure parameters were found.