고출력 LED 탐조등의 방열특성 연구

Abstract

In this paper, thermal design of single searchlight module conducted in order to replace 2000 watt halogen searchlight to 50 watt LED. The thermal design conditions of high-power 5 watt LEDs-based searchlight were designed 12 models (#1~#12) with the different length (L), width (W), and thickness (t) of LED-supporting bar were suggested and optimized with varying LED bar’shape, materials, ambient temperature and bar angle. The LED junction temperature was estimated by using Computational Fluid Dynamics simulation. The thermal design conditions were found as follows; LED bar’ shape: L=40 mm, W=4 mm, t=10 mm, copper material, LED junction temperature of 116.6 ℃, ambient temperature of 50 ℃, total mass of 184 g, and shadowing area of 320 mm2. The difference between the junction temperatures of our fabricated and simulated LEDs-based searchlight modules is about 3 ℃, which confirms the validity of our thermal simulation results. The optical characteristics of searchlight were measured as follows; Input power was 50 watt, peak beam candle power was 2.0*106 [cd], beam angle was 1.4˚. Both searchlight were similar in optical properties but LED searchlight of power consumption was lower than halogen searchlight around 97.5 %.