本研究以逆向方法配合實驗溫度量測值探討鰭片間距、鰭片大小、不同偏心率及邊界條件下，垂直單管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，結合有限差分法、最小平方法及實驗溫度量測值之逆算法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Icepak 15.0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，並且利用經驗公式驗證本文選取的流動模式與網格劃分的合理性。
　　結果顯示在模擬中選擇Zero equation紊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。在自然對流中，隨著鰭片面積的增加，鰭片的平均熱傳係數會降低；隨著鰭片間距的增加，鰭片的平均熱傳係數會增加，不過上升幅度有趨於平緩的趨勢。根據不同的情況，存在著不同的最佳偏心率，當偏心率小於最佳偏心率時，熱傳係數會隨著偏心率的增加而上升；當偏心率大於最佳偏心率時，熱傳係數則會隨著偏心率的增加而下降。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。

In this study, the inverse method and the computational fluid dynamics (CFD) software and experimental methods were used to predict the heat transfer and fluid properties of a vertical annular finned tube heat exchanger. The effects of some physical parameters such as fin spacing, fin diameter, boundary conditions, and eccentricity were investigated. Since the heat transfer coefficient on the fins is not uniform, the fins are divided into several sub-regions. Later, the inverse method applied the finite difference method combined with the least squares scheme and experimental data to estimate the heat transfer coefficient on the fins. The simulations in this study is mainly used for steady state analysis. In addition, the effect of choosing the appropriate flow model and grid points was also studied. A proposed correlation is cited for examining the consistency of the flow model chosen. In order to verify the reliability of the prediction results, this study was compared with other related literature and CFD simulation software packages. The results show that the Zero equation is more suitable for this study than the laminar flow and the standard k-ε turbulence model.

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