本文擬以數值逆算法及計算流體力學商業軟體配合實驗方法來探討散熱鰭片，置於不同高度及外觀下之矩形外殼，觀察其熱傳特性及流場分佈情形。依據文獻鰭片上之熱傳係數為不均勻分佈，在進行數值逆算法之前，先將整個鰭片分割成數個小區域，並假設每個小區域上之平均熱傳係數一未知的常數。本文再以有限差分法及合最小平方法(Least squares scheme)配合逆算法，將外界空氣溫度量測值及鰭片溫度量測值帶入逆算法中估算鰭片上之熱傳係數，為了驗證本文數值結果之正確性與可靠性，本文之平均熱傳係數將和相關文獻之經驗公式的結果相比較。再以逆算法估算結果及實驗溫度量測為基準下，選定計算流體力學商業軟體模式來觀察鰭片上之熱傳係數以及矩形外殼內之溫度與速度分佈。從實驗和模擬結果顯示，鰭片上之平均熱傳係數隨著鰭片間距的增加而增加，隨著機殼高度與鰭片高度比值增加而增加，且在有利散熱外觀之矩形外殼下，對於機殼高度與鰭片高度比值跟鰭片間距散熱效果更顯著。為了驗證數值模擬結果之正確性與可靠性，將鰭片量測位置之計算溫度也和模擬溫度相比較。

The present study applies the numerical inverse methods and fluid dynamics simulation software with the measured temperature data to research the heat transfer characteristic of cooling fins which placed in different height and apparent enclosures. Because of non-uniform heat transfer coefficient distribution on the fin. First, whole of plate fin was divided into several regions, and the heat transfer coefficient on each region is assumed to be unknown constant. And then, the measured temperatures is applied to inverse scheme which was in conjunction with Least squares scheme and finite difference. The inverse scheme results were comparative with empirical formula in order to verify the results were reasonable. The simulation model was determined by the criterion of experimental results and inverse results, and the inner enclosure’s flow and temperature field was investigated. The results showed that the average heat transfer coefficient of fins increased with the increase of fin spacing, increase of enclosure’s height and enclosures which was in favor of heat transfer. Specially, under the circumstance of enclosures which was in favor of heat transfer, the effect of fin’s spacing and height of enclosure were more obvious.

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