本文乃以有限差分法(Finite difference method)並配合最小平方法(Least-squares scheme)及溫度量測值來估算不同風速於溼空氣下之散熱鰭片的平均熱傳係數(Average heat transfer coefficient)、總熱傳量(Total heat transfer rate)和鰭片效率(Fin efficiency)。鰭片上的熱傳係數是非均勻的，為了預測鰭片上之熱傳係數，因此將鰭片分割成數個小區域，並假設每個區域上之熱傳係數為常數。

於強制對流條件下，平均熱傳係數會隨著風速和鰭片高度增加而增加，而鰭片效率會隨著風速增加而減少。於相同風速下，平均熱傳係數會隨著鰭片間距的增大而減少並趨近於單一鰭片之值。結果顯示於強制對流(Forced convection)之環境下，鰭片間距與鰭片高度對本文預測值的影響不容忽視。而為了驗証本文反算法之準確性及合理性，本文之強制對流之平均熱傳係數的預測值將與相關文獻作比較。

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 wet fin for various air speeds. The heat transfer coefficient on this rectangular fin is non-uniform. Thus the whole plate fin is divided into sub-fin regions in order to predict the average heat transfer coefficient on a wet fin. The average convection heat transfer coefficient on those sub-fin regions is assumed to be constant.

The average heat transfer coefficient increases with increasing the air speed and the fin height, and the fin efficiency decreases with increasing the air speed for various fin spacing in forced convection. The average heat transfer coefficient decreases with increasing the fin spacing for a fixed air speed. It can also approach its corresponding asymptotical value obtained from a single fin for the fin spacing above a certain value. The effects of the fin spacing and fin height on the present estimates can not be negligible in forced convection. A comparison of the forced convection heat transfer coefficient between the present estimates and previous results is made in order to evidence the accuracy and reliability of the present inverse scheme.

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