本文以逆向數值方法、最小平方法及方均根誤差搭配實驗量測來探討不同鰭片間距、鰭片高度及是否具相變化熱沉，矩形空腔內矩形鰭片之熱傳特性與流動特性。將熱電偶安裝於實驗內之溫度量測點，並將所得到之溫度值以校正公式進行校正，並使用ANSYS公司的FLUENT配合最小平方法與均方根誤差求得熱源之功率與合適之紊流模型。並使用其後處理功能得到各模型之流場圖與溫度圖，了解空腔內之熱傳特性與流動特性。
結果顯示在三鰭片的模型下，不論鰭片高低，皆選用RNG k-ε模型配合標準壁面函數較為適當，而具相變化熱沉的模型則是選用零方程式較為適當。鰭片高度的增加導致熱對流係數下降，但因增加散熱面積，使散熱效果提升；鰭片間距的增加使熱對流係數上升，因此散熱效果提升，加入相變化熱沉使散熱效果提升。配合後處理軟體觀察各模型之溫度場與速度場，使我們更加了解空腔內之熱傳現象。

This article investigates the heat transfer and flow characteristics of rectangular fins inside a rectangular cavity using inverse methods, the least squares method, and the root mean square error, combined with experimental measurements. The study explores the effects of different fin spacing, fin height, and the presence of phase change heat sink on the heat transfer and flow behavior of rectangular fins within the cavity. The results indicate that in the three-fin model, using the RNG k-ε turbulence model with the standard wall function is more appropriate for all cases, while the model with a phase change heat sink is better suited with the zero-equation model. Increasing the fin height leads to a decrease in the heat convection coefficient; however, it also increases the heat dissipation area, resulting in improved heat dissipation performance. On the other hand, increasing the fin spacing leads to an increase in the heat convection coefficient, thereby enhancing the heat dissipation effectiveness. The addition of the phase change heat sink further improves the heat dissipation performance. By employing post-processing software to observe the temperature and velocity fields for each model, we gain a deeper understanding of the heat transfer phenomena within the cavity.

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