本文以逆算法與CFD軟體配合實驗數據探討以AISI 304不銹鋼為材料之矩形鰭片置於各種不同矩形外殼內之熱傳及流體流動特性，並探討鰭片間距、外殼高度與風速對結果之影響。由於鰭片上的熱傳係數並非均勻分佈，故將鰭片表面分割成數個子區域並假設各子區域之熱傳係數為常數，再利用結合有限差分法、最小平方法及實驗溫度量測值之逆算法來預測鰭片上的熱傳係數；本文亦利用CFD軟體求得於外殼內之空氣溫度與速度分佈以及鰭片表面之溫度與熱傳係數，為了求出本研究較正確之熱傳及流體流動特性，選用適當的流動模式及網格格點數所求得之鰭片熱傳係數，須盡可能分別接近實驗溫度量測值、逆算結果及先前之結果。結果顯示，流動模式對結果之影響不容忽視，於開孔矩形殼內鰭片上的混合對流平均熱傳係數會隨鰭片間距及風扇速度的增加而增大；而鰭片上的平均熱傳係數則隨外殼高度的增加先呈現增加的趨勢，若大於某高度後，鰭片的的平均熱傳係數則愈來愈小，此外，風扇的作用亦使得鰭片間距及外殼高度的影響變小。為了驗證本文逆算法預測結果之可靠度，亦與其它相關文獻之經驗公式以及CFD軟體之模擬進行比較。

This study applies inverse method and FLUENT to determine the heat transfer and fluid flow characteristics of plate-fin heat sinks with various enclosures and whether to install the axial-flow fan inside and exhaust fan on the cabinet. Using measured data to predict and analyze the average heat transfer coefficient on the fin in limited space. The inverse method along with the finite difference method, least squares fitting method and experimental temperature data are applied to determine the heat transfer coefficient. Since the distribution of the heat transfer coefficient on the fin is not uniform, the plate-fin is divided into several sub-fin regions and the heat transfer coefficient in each sub-fin region is assumed to be unknown constant. To obtain correct heat transfer and fluid flow characteristics of plate-fin heat sinks,choose appropriate flow model and number of grid points is very important. The results indicate that the heat transfer coefficient increase with increasing fin pitch and speed of fan in the opening rectangulr enclosure.. But the average heat transfer coefficient decreases when the heights larger than the optimal height. At the same time, the effect of the heights and the fin pitch decreases because of fans for mixed convection. In order to verify the reliability of the inverse method with predicted results of this paper, the present study also in comparison with the empirical corelations of other relevant literature and CFD simulation packages.

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