本文以數值逆算法與實驗方法來預測在自然對流及強制對流下不同鰭片間距之兩種不同交錯排列之管排間距板鰭橢圓管熱交換器的平均熱傳係數 與等溫平均熱傳係數 。由於鰭片上熱傳係數為不均勻分佈，故進行數值逆算法前，先將整個鰭片分割成數個子區域，並且假設每個子區域上平均熱傳係數為一未知的常數。本文之逆算法以有限差分法（Finite difference method）配合最小平方法(Least squares scheme)搭配外界空氣溫度量測值及鰭片溫度量測值來求得本文結果。結果顯示於自然對流條件下， 及 值隨鰭片間距增加而增加。於強制對流條件下， 及 值隨風速及鰭片間距的增加而增加。其他重要的發現為於第二排圓管後方之子區域的熱傳係數一般皆會比其他子區域的值低其緣由為管後低速的尾流區發生所致。另外，前後管排間距小者，第一排管後尾流區可能會影響第二排管後尾流區的流場。為了證明本文結果的可靠度，將本文 值與目前存在之經驗公式及商業計算流體力學軟體所求得結果相比較。此外，本文也利用商用軟體FLUENT配合本文之實驗數據以求得鰭片間空氣流場流動情形及鰭片溫度分佈。

The present study applies the numerical inverse method and experimental method to predict the average heat transfer coefficient and heat transfer coefficient under the isothermal situation on two kinds of elliptic tubes and plate-finned heat exchangers for two-row staggered arrangements in different fin spacings and air velocities. Due to the non-uniform distribution of the heat transfer coefficient, it must divide the plate fin into several sub-fin regions before performing the inverse scheme, and the unknown average heat transfer coefficient on each sub-fin region is required. Next step, 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. Another important result of the study is that and in nature convection increase with increasing the fin spacing S but it tends asymptotically towards a certain limiting or final value. However, and in force convection increase with increasing the fin spacing S and air velocity. The lower average heat transfer coefficients concerned with the upstream and wake fin regions of the 2nd row, The concentrated elliptic tube of staggered plate-finned may increase the pressure drop. A computational fluid dynamics ( CFD ) program called Fluent for verifying the Reliability is used in the analysis.

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