大功率LED工矿灯重力管散热器的传热性能研究

The heat transfer performance of high-power LED gravity heat pipe radiator

LED具有环保、节能、体积小、使用寿命长等诸多优点,开始逐步取代传统光源.但是,目前LED的电光转换效率较低,工作中约有80%电能转化为热能.随着功率密度和集成度的增加,传统的冷却技术已难以满足其散热要求,散热问题已大大阻碍了LED照明的发展.针对上述问题文章研制了一种一体化重力管翅片散热器,并应用于大功率LED工矿灯.对散热器进行了性能测试,实验结果表明:不同功率下,重力管散热器启动性能良好,达到稳态的时间几乎都为36 min;散热器具有良好的均温性能,热端最大温差为3.19℃,冷端最大温差低于3℃.传热过程中,翅片热阻占总热阻的比例最大;实测加热器中心点温度都在83℃以下.

Light-emitting diode( LED) has a series of outstanding advantages such as environmental protection,energy saving,small size,long life and so on. Gradually,it begins to replace traditional lamps. However,at present,electro-optical conversion efficiency of LED chips is low and about 80% of electrical energy has converted into heat at work. With the increasing of the power density and the degree of integration,conventional cooling techniques have been unable to meet the LED chips' cooling requirements. Thermal issues become the greatest technology bottleneck that impacts the development of LED lighting. A integrated radiator is designed and produced with thermosiphon heat pipe and fin. The radiator performance test is conducted. The results showed that the starting performance of the gravity heat pipe radiator is good enough and almost all of them spend about 36 min to reach steady state under different power. Gravity pipe radiator has a very good average temperature performance which the maximum temperature difference of the heating surface is 3. 19 ℃. The maximum temperature difference of the condensing surface is lower than 3 ℃. External fin heat exchanger'thermal resistance is a major obstacle throughout cooling process of the heat pipe radiator. The maximum temperature of measured center point does not exceed 83 ℃ in the heat source.