本文以逆向方法及實驗特定溫度點的量測搭配ANSYS ICEPAK 15中各種流動模式的比較，確立合適於散熱水平鰭片置於封閉空腔內的熱壁中之系統的流動模式，再經由合適的流動模式預測水平鰭片之熱傳導係數及觀測鰭片對於封閉空腔內的流場產生之影響。實驗方面以穿孔及未穿孔鰭片隨鰭片位置、鰭片間距及鰭片數量等測試對鰭片表面的熱傳導係數及鰭片本身周圍的流場產生之影響。並利用ANSYS ICEPAK 15進行網格測試，研究網格劃分對於系統求解的影響。結果顯示雙鰭片在熱傳導係數的表現上複雜許多，鰭片間邊界層的互相影響或鰭片與空腔上下邊界的互相影響，使得鰭片之熱傳係數不再只是隨著鰭片間距增加而上升，透過以實驗數據搭配數值結果的溫度分布圖及速度流線圖去分析實驗的實驗數據的種種現象，另外嘗試以無因次參數進行流場行為之說明，並和研究結果進行互相驗證，最後為了驗證結果之可靠性及可用性，將所求結果與相關參考文獻之現象比較，得到穿孔鰭片確實能破壞鰭片周圍之邊界層，促使鰭片附近的流場趨於紊亂，流場之流速提升，鰭片本身的熱傳導係數也有所提升。

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 fins on a hot wall in a cavity. The effects of some physical parameters such as fin spacing, fin diameter and fin numbers, are examined. 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. With the methods of Rayleigh number with references and the comparsion between experimental and numerical results to obtain the appropriate flow model are included. Effect of perforation on fins in a cavity around fin is investigated by the temperature contour, velocity field and heat transfer characteristic. Perforation cause perturbation and reinforce heat convection around fins. Increase of Heat transfer coefficient and the change of temperature distribution on fins can be observed under the influence of perforation. Perforation cannot cause additional effect on fins. We found that the incease of heat transfer coefficient by the effect of perforation didn’t change under different parameters, such as fin postion, fin spacing and fin numbers under investigation. Although the effect of perforation can increase heat transfer coefficient on fins, the use of perforation on fins exists many challenges.

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