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。實驗方面以不同高度鰭片隨鰭片位置、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。結果顯示上下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左邊界的互相影響，使得鰭片之熱傳係數不再只是隨著鰭片高度及間距增加而上升，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，得到上下兩鰭片間距越大的確有利於系統對流，流場之流速提升，鰭片本身的熱傳導係數也有所提升。

In this study, inversion methods, computational fluid dynamics (CFD) software and experimental methods are used to predict the heat transfer and fluid characteristics of the vertical fins in the cavity. The influence of certain physical parameters (such as fin length, clapboard length and distance between fin and clapboard) was checked. The inverse method combines the least squares scheme and the experimental data to apply the finite difference method to estimate the heat transfer coefficient on the heat sink. The Rayleigh number method and temperature reference method are used, and the experimental results and numerical results are compared to obtain a suitable flow model. Through the temperature profile, velocity field and heat transfer characteristics, the influence of the clapboard on the heat sink in the cavity around the heat sink is studied. The clapboard will destroy the internal flow field and reduce the heat dissipation effect of the vertical fins. At the same time, the longer vertical fins will reduce the heat convection effect in the cavity, and the heat dissipation effect of the vertical fins is poor. When the clapboard is close to the vertical fins, the area between the two objects is prone to heat accumulation, which reduces the heat transfer effect. In this experiment, the temperature distribution on fins of various sizes has little difference. It can be seen that the thermal convection in the cavity in this experiment is the main reason that mainly affects the heat dissipation of the vertical fins.

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