本文以有限差分法、最小平方法之逆算法搭配實驗溫度量測值來探討不同鰭片間距、鰭片孔洞大小、孔洞位置及邊界條件，垂直單管穿孔環狀鰭管式熱交換器之熱傳特性與流動特性。由於鰭片上的熱傳係數為不均勻的分布，故將鰭片劃分成數個小區域，而後把熱電偶安裝於小區域上以量測不同條件下量測溫度來預測鰭片之熱傳係數。為了驗證其準確性，本文使用商用軟體 ANSYS 進行數值模擬與本文逆算法所得之逆算值做比較，探討不同流動模式與網格劃分對於不同物理模型的適用度。
結果顯示在模擬中選擇適當的網格數量及laminar層流模式所求得的結果較符合實驗量測溫度與逆向方法結果。模擬結果中，隨著鰭片孔洞半徑增加，鰭片的平均熱傳係數會降低。隨著孔洞位置變化，鰭片的平均熱傳係數會增加，且鰭片間的空氣流動也會不同。在不同的邊界條件下，開放式邊界條件之平均熱傳係數會大於封閉式邊界條件。在固定的範圍內平均安置鰭片，間距較近的鰭片能產生最大的散熱量，所求得熱傳係數之逆算結果配合實驗與模擬來與先前結果或其他相關文獻之經驗公式相比較。

The present study applies the inverse method and computational fluid dynamics (CFD) software along with experimental method to predict the heat transfer and fluid characteristics of vertical annular finned tube heat exchanger. The effects of some physical parameters such as fin spacing, size of perforation, position of perforation, boundary condition are examined. Due to the heat transfer coefficient on the fin is non-uniform, so the fin is divided into several sub-regions. Later, the inverse method applied finite difference method in conjunction with the least-squares scheme and the experimental data to estimate the heat transfer coefficient on the fins. Simulation in this study are all steady state analysis. Furthermore, how to choose the appropriate flow model and the effect of the grid point are also investigated. In order to verify the reliability of the predicted result, the present study also compares with other relevant literature and CFD simulation packages. The result show that laminar is more suitable for this study than zero equation and standard k-ε turbulence flow model. The heat transfer coefficient has been developed for open system and it increases with the fin spacing and size of perforation. And it changes with different position of perforation.

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