Study On Heat Dissipation Of High Power Airborne LED Light

LED,as a fourth-generation lighting source,is widely used in the fields of park lighting,street lighting,traffic signals,home lighting and aviation lighting.70%~80% energy could be converted to heat in LED,results in the junction temperature of LED chip rising,then voltage dropping,the red shifting,the luminous efficiency and life reducing.It is of great significance to balance between the volume limitation and the heat dissipation performance,since LEDs are being gradually applied on airplane lights with higher and higher power.This paper displays the mechanism of the LED and the heat generation,and the research situation at home and abroad.Based on the thermal resistance and thermal resistance network,the heat dissipation path of the high-power LED was analyzed,and the key link was pointed out.Respectively by thermal resistance network calculation and numerical simulation analysis,LED aluminum plate heat dissipation performance was carried on,the results showed that the LED heat sink,insulation layer was the main part of of thermal resistance but thermal resistance have large difference between two ways,largely due to the influence of transverse thermal resistance.Through the simulation analysis,the optimal aluminum substrate length is 10~12mm.Based on large thermal resistance of insulation layer,it was proposed that the embedded ceramic plate and thermoelectric separation aluminum base plate,the cooling performance was obviously better than the traditional LED aluminum base plate.The influence of fin heat sink geometric parameters,environmental temperature,and thermal power were analyzed,obtaining the optimal fin parameters,and through the orthogonal experiment to study the effect of fin parameters.Finally,based on the optimized parameters,the maximum thermal power of YY-1 is 95 W and 40 W when the ambient temperature is 25℃ and 70℃ respectively.