單晶高功率二極體應用於球泡燈散熱研究

Abstract

近年來高功率二極體(High Power Light Emitting Diode)的應用已經越來越廣泛,不外乎是應用於室內與室外照明上.室內照明則取代傳統的白織燈泡與冷陰極管式.LED不但有著低功耗與高光通量輸出,色溫可變,演色性較冷陰極管式高,封裝尺寸小與製造上不需要加入重金屬氣體如”汞”等對環境有害之物質. 目前為止,已大量生產的LED每瓦輸出的光通量已經達到130流明,但是隨之而來的散熱問題卻是當前的難題.以球泡燈為例,目前主流尺寸為IEC-A60規格,如何在有限的空間裡應用自然對流的方式創造最好的散熱效率是目前眾多研究的方向,根據散熱原理熱傳行為可分為三大要素:一,輻射,二,對流,三,傳導. 輻射與散熱裝置的表面處理有關,對流與溫度差改變空氣的密度有關,傳導與所選用的散熱片材質有關. 綜合上述熱傳三大要素,本研究課題在於如何提高輻射效率,熱對流係數與熱傳導係數.在科技發達的今天,電腦浮點運算能力已經超過每秒十億次,使用數值分析模擬軟體去做初期的散熱模擬也是目前熱門的方向.本論文使用Icepak作為模擬評估軟件,藉由模擬找到可能的解決方案,進而尋求最佳化設計.

In recent years, the application of high power diode (High Power Light Emitting Diode) has been more and more widely, no more than is used in indoor and outdoor lighting, indoor lighting to replace traditional incandescent bulbs and cold-cathode fluorescent lamps (CCFL) . LED not only has a low power consumption and high luminous flux output, variable color temperature, high color rendering better than CCFL, small package size and not need to add heavy metal gases such as mercury. So far, the mass production of LED luminous flux per watt output has reached 130 lumens, followed by cooling the current problem. Example, the bulb mainstream size is following IEC-A60 specification. Many researches direction is the application of natural convection in a limited space to create the best cooling efficiency, heat dissipation principle of heat transfer behavior can be described to three elements: radiation, convection and conduction. Radiation efficient is decided by surface coating, the convection is decided by temperature difference to change the density of the air, and the conduction is decided by material thermal conductivity performance. The heat transfer three elements, the subject of this study is how to improve the radiation efficiency, thermal convection and conduction coefficient. In the technological advances of today, the computer floating point capability has been more than billions of times per second, using the numerical analysis simulation software to do is currently popular way to estimate thermal performance in preliminary study. This thesis hopes to find the optimum solution by using simulation software Icepak.