本文以實驗搭配逆運算法與Icepak探討橢圓板鰭管式熱交換器熱傳特性的研究，並探討橢圓鰭片間距、正向風速與兩種橢圓管尺寸對所得結果之影響。由於鰭片各點實際上的熱傳系數並不均勻，為了求得鰭片的平均熱傳系數，首先將鰭片劃分成數個小區域，並假設每個小區域內的熱傳係數為定值，接著搭配有限差分法及最小平方法來藉由實驗所得鰭片特定位置的溫度，以逆算法求得平均熱傳系數。本文也利用Icepak軟體求得實驗條件下的鰭片表面溫度與熱傳系數。結果顯示，增加鰭片間距可以使熱傳係數上升，並且會趨近於定值。提升流體風速可以使鰭片熱傳係數大幅提升，效果比增加鰭片間距還要好，但缺點是需要持續的外力來維持風速。當鰭片外緣相同時，中心的橢圓管徑越大，鰭片熱傳係數越大，但是風速越快時不同管徑的熱傳係數差距反而越小。另外，本文也利用模擬軟體分析比較不同情況下的鰭片周圍流場，並探討不同流動模式與網格切割對模擬結果之影響。

This study applies inverse method and Icepak to determine the heat transfer and fluid flow characteristics of elliptical fin and tube exchanger with various fin spacing, flow velocity and various tube size. Since the distribution of the heat transfer coefficient on the fin is not uniform, the plate-fin is divided into several subregions and the heat transfer coefficient in each subregion is assumed to be unknown constant.Then using inverse method with measured temperature data to predict and analyze the average heat transfer coefficient on each subregion and then the whole region. The inverse method along with the finite difference method, least squares fitting method and experimental temperature data are applied to determine the heat transfer coefficient. Icepak is applied to get temperature, heat transfer and coefficient.
The results indicate that the average heat transfer coefficient increase with increasing fin spacing and flow velocity but will be close to a value when the fin spacing is infinite long. The results also show that the average heat transfer coefficient increases when tube size is large but the difference between two different tube size will decrease when flow velocity increases. In order to verify the reliability of the inverse method with predicted results of this paper, the present study also compares the empirical corelations of other relevant literature with CFD simulation packages.

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