CHIMNEY-ENHANCED DESIGN APPLIED ON THE THERMAL MANAGEMENT OF LED VEHICLE HEADLAMP

摘要

LED vehicle headlamp consists of several high-power LEDs and thermal module inside an enclosed space, and locates near the high-temperature engine compartment. Certainly, these factors results in a challenging task on the thermal management of headlamp. Obviously, the temperature stratification inside this bounded region is an unfavorable phenomenon for the natural-convection thermal module. This study utilizes the chimney effect to achieve a more uniform temperature distribution and thus enhance the heat-dissipation ability. Firstly, an enclosed space is selected for executing the parametric study on the chimney geometry. Several effective alternatives are obtained and verified via both numerical and experimental means on the chimney design. Also, a significant 4.6 degrees C reduction on LED junction temperature is attained on the best chimney-enhanced module. Then, these guidelines are applied to a commercial LED headlamp. Consequently, a range of 3.8 similar to 4.6 degrees C decrease on LEDs is found for this innovative chimney thermal module.