Experimental investigation on active heat sink with heat pipe assistance for high-power automotive LED headlights

Abstract

Compared with traditional halogen headlights, LED has obvious advantages in energy consumption, photoelectric efficiency, luminous flux, and life span. However, the thermal management of LEDs is usually limited by space. This paper proposes a novel design of a heat pipes assisted compact heat sink (HPACHS) for LEDs to reduce the LED junction temperature. The thickness of the double-sided LED can be reduced to 1.5 mm since there is no multilayer structure, and the double-sided LED headlight can emit more concentrated light. The results show that HPACHS can cool the 34 W LED substrate to 100.32 °C at an ambient temperature of 26 °C, with a cooling fan power of only 0.267 W and a thermal resistance from the LED base to the environment of 2.17 °C/W. The minimum thermal resistance of HPACHS is 1.86 °C/W, with a heat load of 18 W. The heat sink is 71 mm long and the maximum outer diameter is 38 mm. Therefore, as an efficient and high-power LED cooling device, this compact active radiator has sufficient application prospects and can be applied to the thermal management of automobile headlights.