EXPERIMENTAL STUDY OF THERMAL MANAGEMENT OF LED AUTOMOTIVE HEADLAMPS USING HEAT PIPES

摘要

In this research, high-power white LED chips are used in automotive headlamp low beam system design. As more energy is pushed through the LED diode junction, heat removal becomes a critical issue. To assure LED device lifetime, quantum efficiency, and LED color, the diode junction temperature must be maintained within a specified band. The novel cooling devices are presented based on the nanofluid heat pipes for high-power LED headlamps. The radiator models are designed and its thermal performance is evaluated by the LED case temperature and the total thermal resistance. The optimum filling rates for both water-based heat pipe and nanofluid-based heat pipe is about 21% at a given heating power of 25 W. Parametric studies are carried out to compare the effects of the heat pipe distributions (linear and disperse), and inclination angles (0 degrees, 45 degrees, and 90 degrees) on the comprehensive cooling performance. The start-up performance is investigated with respect to different tilt angles. The results indicate that the heat transport capacity and the start-up performance are enhanced by gravity. It is shown that the proposed heat pipes base model is capable of addressing the issue of high-power LED headlamps thermal management.