자동차 LED Head Lamp 방열을 위한 히트싱크의 수치해석에 관한 연구

Abstract

This thesis was conducted a simulation on the radiant heat performance according to factors of design of heat sink for cooling of the automotive LED head lamp. The heat sinks were designed with 5 different types to fit the limited internal space by formula based on an existing product (Type 1). Designed heat sinks of five types were analyzed by ANSYS CFD V12.1, and the analysis results were compared with the existing type. The conditions of simulation were applied junction temperature of 160℃ and cooling fan operation. The results of simulation were analyzed temperature distribution and average temperature, air flow characteristic, heat flux etc. Through these analyses were obtained following conclusion.

1. The temperature distribution of existing heat sink (Type 1) was showed the thermal accumulation to the top of the fin and it was the maximum average temperature of 125℃ according to the temperature distribution. Designed Type 2 showed the low-temperature distribution toward the top of heat sink and it was the minimum average temperature of 101.9℃. 2. Air flow of the existing Type 1 was passed rapidly in the middle of heat sink, and the average velocity of fluid was 100.603 m/s. Designed Type 6 was increased in flow speed at the central, and the average velocity was 113.983 m/s as the maximum.

3. The design type of Type 2 was heat flux of the maximum as 44430 W/m2, and the thermal conductivity was showed highest 884.170 W.

This thesis was researched on the correlation of the cooling performance according to the heat sink structure and the fin shape. Through numerical analysis, could be confirmed heat sink Type 2 as the best results. In addition, by this study in regard to the heat radiant and flow characteristics of LED head lamp at the limited internal space is thought possible to optimal heat sink design and production.