Structure optimization of heat sink for high power LED street lamp

Light emitting diode (LED) is now widely used in many fields including traffic lights, vehicle backlights and liquid crystal display (LCD) displays because of their long life, good illumination efficiency and low energy consumption. For the high power LED street lamp, a low operating temperature is essential for LED chips. However, it's waste and meaningless to increase the size of heat sink for high power LED street lamp immoderately. In this paper, structure optimization of heat sink is studied on the condition that the heat sink is sufficient for cooling demand of 196W LED street lamp. 1/7, 2/7 and 3/7 length diminution of the heat sink are studied respectively. Results show that temperature of plate surface is increased 16°C with 3/7 bulk and weight reducing. And cross-sectional shape optimization of fin is also studied. The result show that the bulk and weight of fins are reduced over 50% with only 0.42°C temperature rise. The results of this work provide useful guidelines for thermal management of the heat sink without affecting the cooling demand of high power LED street lamp.