A single unit cooling fins aluminum flat heat pipe for 100Â W socket type COB LED lamp

Although the LED light has higher energy conversion efficiency compared with the conventional metal halide lamp, it is well known that there is a thermal burden due to the poor photoelectric conversion efficiency of the semiconductor diode. SMD (Surface Mount Device) LED lamp which has been mainly used has induced a problem of poor optical efficiency though it has relatively large heat dissipation area. Much effort has been put to improve the optical efficiency through COB (Chip on Board) LED lamp, but the thermal problem particularly in the over 100 W application is still exist. As the studies for applying the heat pipe to the high power LED, an embedding technology the heat pipe in the MCPCB (Metal Core Printed Circuit Boards), loop heat pipe, and a columnar heat pipe for 90 W, etc. were developed and may apply to COB LED lamp. In this paper, a single unit cooling fins aluminum flat heat pipe (AFHP) with U shape is developed for the 100 W COB LED lamp with 120 ∗ 120 ∗ 170 mm3 of small volume and socket type electric connection. The U shape AFHP module has less than 900 g, low price by extrusion method and socket type lamp, therefore replacement and maintenance of the lamp for factory-light or street-light could be easily conducted. Through the study, a single unit cooling fins AFHP is designed and fabricated. And the heat transfer characteristics of the AFHP with two condensers have been investigated, and the junction temperature of the COB LED module was also evaluated within 85 °C at 100 W of input power.