LED節能杯燈散熱鰭片之參數設計與熱傳影響研究

Abstract

發光二極體（Light-emitting diode，LED）是一種可產生光源的半導體電子元件，在現今也發展了多種形態之高亮度LED，比起過去傳統燈具擁有多種優勢，如：發光效率較高、耗電量低、使用壽命長且較環保等。但LED在電能轉換為光源的過程中，會有部份能量轉換為熱能。此時當熱量積存於LED封裝晶片，如無法有效進行散熱，將嚴重影響LED的發光與工作效率，以及使用壽命。而在現今對於LED較常見之散熱技術，為搭配散熱鰭片將產生之熱量傳遞至鰭片，並透過空氣自然對流將熱傳遞出去。因此本研究主要透過電腦數值模擬方式，並使用Icepak熱傳分析軟體進行模擬實驗。透過改變LED散熱鰭片之數量、傾斜角度、材質以及表面放射率，探討此四種改變參數分別對於LED溫度之熱傳影響情形。而研究結果顯示，隨著鰭片數量增加，LED整體溫度會隨之降低，但當數量增加到一定值時，LED整體溫度反而會因此提升；隨著鰭片傾斜角度增加，LED整體溫度會因此持續提升；而散熱鰭片使用不同材質，LED整體溫度也會因材質的不同而產生改變；隨著放射率數值增加，LED整體溫度會隨之持續降低。因此瞭解此四種改變參數會對於LED散熱鰭片熱傳性能產生影響。The light-emitting diode (LED) is a light source that can be used to produce various semiconductor components. Modern advancements in LEDs include a number of high brightness LED illuminants offering a number of advantages when compared to conventional lighting such as: high luminous efficiency, low power consumption, long service life, and better environmental friendliness. However, when LED converts energy into visible light, part of the energy will generate heat, leading to heat accumulation in the LED package. Poor heat dissipation will significantly affect LED light emission, work efficiency, and service life. Common forms of LED heat dissipation technology include heat fins, wherein heat generated by the LED package is transferred to the fins, allowing natural convection of air to transfer the heat into the ambient environment. This study conducts computer numerical simulation experiments by using Icepak heat transfer analysis software. A total of 4 variable parameters are used, namely: (1) number of LED heat fins, (2) tilt angle, (3) material, and (4) surface emissivity, to investigate LED temperatures and heat transfer scenarios. Results show that overall LED temperature decreases with increasing number of fins up to a certain number of fins; overall LED temperature assumes a continuous cooling phenomenon when certain tilt angles are used; overall LED temperature differs according to the fin materials; and increasing surface emissivity will reduce overall LED temperature. Better understanding of these four parameters will allow improvements to LED cooling fin designs and augment LED heat transfer performance.