本文乃以有限差分法(Finite-difference method)並配合最小平方法(Least-squares scheme)及溫度量測值在絕緣封閉箱內來估算矩形鰭片上之平均熱傳係數(Average heat-transfer coefficient)、總熱傳量(Total heat transfer rate)和鰭片效率(Fin efficiency)。由於鰭片上的熱傳係數並非均勻。為了預測鰭片上之熱傳係數，因此整個鰭片分割成六個小區域及八個小區域，並假設每個區域上之熱傳係數為常數。結果顯示，平均熱傳係數會隨著鰭片間距增加而提高，卻隨鰭片高度增加而減小。此外並顯示鰭片分割成六個小區域之熱傳特性近似於八個小區域之值。本文所估算之平均熱傳係數與相關文獻之經驗公式相比較，以驗證本文逆算法之準確性及經驗公式之合理性。

The present study applies the finite-difference method in conjunction with the least-squares scheme and measured temperatures to estimate the average convection heat-transfer coefficient, total heat-transfer rate and fin efficiency on a vertical rectangular fin in an insulated enclosure. The heat-transfer coefficient on this rectangular fin is very non-uniform. In order to predict the average heat-transfer coefficient on a plate fin, the whole plate fin is divided to six and eight sub-regions. The heat-transfer coefficient on those sub-regions is assumed to be constant. The results show that the average heat-transfer coefficient increases with increasing the fin spacing and decreases with increasing the fin height. In addition, the heat-transfer characteristics of the fin divided into six sub-regions can approach values of the fin divide into eight sub-regions. In order to demonstrate the accuracy and reliability of the present inverse scheme, a comparison of the average heat-transfer coefficient between the present predicated results and those obtained from correlation recommended by current textbook is made.

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