本文為優化板鰭式加熱器於空腔內之散熱效果，本文使用逆向數值方法為運用實驗溫度量測值與逆算法搭配CFD軟體精確未知物理量之方法，並於後續探討在穿孔鰭片在空腔中自然對流的熱傳特性。此外，可利用CFD軟體之後處理功能提供三維可視化之流場、溫度場等重要參數以利於後續的分析，本文為了確保CFD軟體計算的正確性，事先進行網格劃分及選用精確度較高的紊流數值模型是必要的，結果顯示在Nc = 1的情況下，選用零方程式作為紊流模型計算已具有足夠的準確性且可以大量縮短計算時間，僅Nc = 3的情況下須選用RNG k-ε搭配標準壁面函數處理較符合實驗結果。
本文透過改變鰭片長度、鰭片穿孔數目、冷壁開口數量及高度，探討其對∆T_f與¯h_f之影響，結果表示Lf從30 mm增加至70 mm時，∆T_f分別為3.138 K、5.627 K 及6.988 K，分別提升79 %及24 %，利用熱傳面積的增加與流體進行更多的熱交換，得到更好的散熱較果；改變鰭片穿孔數量，由模擬結果可得Nf = 1與Nf = 3的h ̅_f各為2.69 W/ m2·K及2.81 W/ m2·K，提升約4.8 %，再次驗證穿孔數量的提升能夠增強鰭片附近的熱對流強度，且由流線圖可得鰭片穿孔附近的流速提高至約0.1 m/s；改變冷壁開口高度及數量，Nc = 1時，H_d=H_c/4提高至H_d = 3H_c/4，h ̅_f分別提升5.5 %、1.4 %；Nc = 3時，h ̅_f提升78.5%。此研究結果皆表明三種變因皆可作為改善熱傳效果的參數

The present study shows an optimization of cooling in heat exchangers. Appling the inverse numerical method and computational fluid dynamics (CFD) software along with experimental method to predict the heat transfer and fluid characteristics of a fin on the hot wall. In order to verify the temperature distribution and flow characteristics, selecting an acceptable flow model and mesh grid independence study are necessary. In the cases of N_c= 1, The numerical results and experimental temperature data are closest when the zero equation model is used. In the cases of N_c= 3, The flow model need to choose RNG k-ε model with standard wall funtion. This study discusses the effect of ∆T_f and ¯h_f by changing parameters, such us fin lengths(L_f), perforation numbers(N_f), opening altitude(H_d) and opening numbers(N_c). The results in CFD simulation show that when L_f increases from 30 mm to 70 mm, ∆T_f increases by 79 % and 24 %, respectively. When N_f increases from 1 to 3, h ̅_f increases by 4.8%. Besides, It can be seen from the streamline diagram that the flow velocity around the perforated fin increases to about 0.1 m/s. In the cases of N_c= 1, when H_d increases from H_c/4 to 3H_c/4, h ̅_f increases by 5.5% andd 1.4%. In the cases of N_c= 3, h ̅_f increases by 78.5%. The results show that this four variables can be the control parameters for heat and fluid flow for cooling periods.

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