本文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各種不同型式之散熱鰭片，置於具開孔之矩形外殼，其熱傳特性及流場分佈情形。因鰭片上之熱傳係數可能為不均勻分佈，故於進行數值逆算法之前，整個鰭片將先被分割成數個小區域，且每個小區域上之平均熱傳係數假設為一未知的常數。而後，本文以有限差分法之反算法配合最小平方法(Least squares scheme)、外界空氣溫度量測值及鰭片溫度量測值來預測鰭片上之熱傳係數，除此之外，本文也以計算流體力學商業軟體來求得壓力降、鰭片上之熱傳係數以及矩形外殼內之溫度與速度分佈。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，隨著鰭片高度增加而減少，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，且於鰭片量測位置之計算溫度也將和量測溫度相比較。除此之外，本文亦將探討網格數對數值結果的影響。

The present study applies the numerical inverse methods and computational fluid dynamics commercial software with the experimental to explore a variety of different types of cooling fins, placed in the openings of rectangular shell, the heat transfer characteristics and flow field distribution. Due to the non-uniform distribution of the heat transfer coefficient, the whole plate fin is divided into several sub-fin regions before performing the inverse scheme, and the average heat transfer coefficient on each sub-fin region is assumed to be unknown. Later, the inverse scheme of the finite difference method in conjunction with the Least squares scheme and experimental measured temperatures is applied to determine the present results. In addition, the paper also by computational fluid dynamics commercial software to obtain the pressure drop, the distribution of temperature and speed of the fins on the heat transfer coefficient as well as within the rectangular enclosure. The results show that the average heat transfer coefficient of fins increased with the increase of fin spacing and reduced as the fin height increases, in order to verify the accuracy and reliability of the numerical results, the average heat transfer coefficient and the associated compared to the literature of the results of the empirical formula, and calculate the temperature of the fin measurement position will also be compared and measured temperature. In addition, this paper will also explore the impact of the grid number on the numerical results.

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