本文主要是以有限差分法(Finite difference method)並配合最小平方法(Least-squares scheme)及溫度量測值來預測不同風速及濕度下之鰭管鰭片上有冷凝現象時的平均熱傳係數(Average heat transfer coefficient)、熱傳量(Heat rate)和鰭片效率(Fin efficiency)。本文乃以最小平方法來修正預估值，直至量測點之溫度計算值和溫度量測值之差甚小為止。為了欲驗證本文預測值的可靠性，本文先以一維逆向熱傳導(Inverse heat conduction problem)問題來進行分析，所得預測結果將和先前結果相比較。結果顯示, 相對濕度(Relative humidity)越高則鰭片上之熱傳係數及熱傳量也會隨之增加，但鰭片效率則隨之遞減。為了更進一步探討板鰭片之熱傳現象，吾人提出二維逆向熱傳導問題來進行分析，所得預測結果將和一維逆向分析之結果來進行比較。

　　The present study applies the finite difference method in conjunction with the least-squares scheme and measured temperatures to predict the average convection heat transfer coefficient, total heat rate, and fin efficiency on the rectangular vertical wet fin of plate finned-tube heat exchangers for various air speeds and relative humidities. The least-squares minimization technique is applied to correct the present estimates until the sum of the squares of the deviations between the calculated and measured temperatures are minimum in the present study. In order to show the reliability of the present estimates, the present study will apply the 1-D inverse heat conduction problem to perform the inverse analysis. A comparison between the present estimates and the previous results is made. The results show that the heat transfer coefficient and the heat rate on the fin increases with the relative humidity, but the fin efficiency decreases with increasing the relative humidity. In order to investigate the heat transfer performance on a fin of plate finned-tube heat exchangers further, the 2-D inverse heat conduction problem is also applied to determine the present estimates. The present estimates obtained from the 2-D inverse analysis compare with those obtained from the 1-D inverse analysis.

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