液冷封裝高功率LED照明之自然對流熱傳研究

Study of Free Convection Heat Transfer for the Liquid-Cooled Package of High-Power LED Illuminations

顏庭堃(Ting-Kuen Yan)

指導教授 ： 周榮源

國立虎尾科技大學/工程學院/機械與機電工程研究所/碩士(2010年)

摘要

本研究主要是探討液冷封裝高功率LED照明之自然對流熱傳現象。將高功率LED陣列在矩形密閉容器中，以金屬殼體當成散熱基本結構，搭配三種透光且不導電之空氣、矽油和FC-40流體改變熱傳性能，藉由改變輸入功率3W、6W和9W，不同擺置角度0°、90°和180°照明下探討其自然對流熱傳現象。數值模擬主要是使用COMSOL模組進行分析LED整體受到輸入功率3W、6W和9W以及不同擺置角度0°、90°和180°照明之影響；實驗量測部分則是自行設計組裝一套自然對流實驗平台，擺置角度在0°照明下，以7個溫度量測點記錄LED整體模組溫度變化，其包括LED基板溫度、LED周圍流體溫度、金屬殼體外壁四個位置點溫度和環境溫度，分別進行量測三個輸入功率及三種流體特性所產生之變化情形，希望以實驗量測值來驗證分析模擬結果之準確性。並將模擬分析與實驗量測結果作比對驗證。分析研究結果對於不同的擺置角度會對LED晶片接面溫度造成影響，擺置角度在90°有較佳的降低晶片接面以熱阻來探討三種擺置角度下，改變流體對於液冷封裝高功率LED熱傳性能的影響。其中在擺置角度90°中，填充FC-40流體相對於空氣可以改善最佳的熱阻值為2.07~2.86%。

關鍵字

液冷散熱 ； 自然對流 ； 高功率LED ； 熱阻

並列摘要

In this study, natural convection heat transfer for the liquid-cooled package of high-power LED illumination module is investigated. Numerical simulations and experimental measurements are adopted to explore the heat transfer characteristics for the high-power LED arrays which are enclosed by a metal enclosure and are immersed in one of the three kinds of fluids, air, silicone oil, and FC-40, respectively, with transparent and electrical resistance characteristics. The COMSOL software is adopted to analyze the effects when the LED illumination module is subjected to the input power of 3W, 6W, and 9W, respectively, and is aligned to the orientation of 0°, 90°, 180°, respectively. In experimental measurements, the illumination module aligned in 0° orientation is investigated. Temperature responses at 7 different locations including one point for LED substrate position, one point for LED’ ambient fluids, one point for acrylic enclosure’ air, and four points for the metal enclosure wall, respectively, are measured for three input powers and three different fluids, respectively. Numerical results are compared to experimental data for validation of the accuracy of this study. According to the analyzed results, junction temperatures are changed due to orientation variations of illumination module and the 90° orientation is shown to be with the lowest junction temperature. Regarding to thermal resistances analyses, in the 90° orientation, resistance value for the FC-40 filled case is 2.07~2.86% lower than the air filled case.

並列關鍵字

Liquid Cooling ； Natural Convection ； High-Power LED ； Thermal Resistance

參考文獻

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