本論文主要探討波狀外形設計於鰭片之應用，利用商業模擬軟體ESI CFD-ACE+進行模擬分析，並搭配拉凡格氏法(Levenberg-Marquardt Method)將模型之設計參數最佳化，最後再利用後處理軟體ESI CFD-VIEW分析數值結果。本論文之模型均在固定體積之條件下進行比較。
論文第二章以文獻[1]為基礎，探討反置鰭片(Inverted fins)形狀設計對於系統最高溫度之影響，並以規則正弦波(Regular Sine Wave)進行外形設計，以振幅及角頻率為設計參數。在本章中以邊界等溫及邊界對流等兩種邊界條件進行最佳化設計，以系統均溫極小化為目標，期望可得到極小化之系統最高溫度。兩種邊界條件設計中均比照文獻[1]，分別以不同分枝數N=1、N=2、N=3、N=4進行最佳化設計，將反算後之結果與其它形狀設計之文獻做比較均有顯著的溫降效果。然而為證明本數值方法之有效性，本論文另外以系統溫降20%與40%進行設計，同樣可求得目標均溫下之設計參數。
論文第三章將此波狀設計運用於傳統板式鰭片，不同於第二章，在此參考文獻[2]之設計，以變形正弦波(Deformed Sine Wave)作為外形設計，即於振幅及角頻率兩參數中加入權重係數以生成曲線。此部分內容以底板均溫極小化為目標，期望藉由曲線外形之改變使鰭片達到更好的散熱效果，文章中亦有與規則正弦波設計之鰭片做比較，且除溫度外也針對變形前後之鰭片壓降做探討。結果顯示，此設計不僅能有效使底板均溫下降，最佳化之鰭片設計亦有減少壓降之效果。
在論文最後委託工廠將鰭片以放電線切割加工，並以風洞、電熱片與熱像儀完成本實驗，將熱像儀所紀錄鰭片底板之表面溫度與商業套裝軟體CFD-ACE+模擬之理論值做比對，結果顯示實驗值與本模擬有非常相近之結果。

A shape design problems in determining the optimal geometry of wavy-shaped inverted fins and WPFHS (Wavy-shaped Plate Fin Heat Sink) are discussed in this work in two and three-dimensional domains, respectively. Besides, all the cases are investigated under a fixed volume condition. The commercial software CFD-ACE+ and the Levenberg-Marquardt Method (LMM) are utilized to estimate the optimum design variables.
Based on literature [1], the objective of chapter two is to obtain the optimal shape design of a wavy-shaped cavities penetrated in to a heat generating body by minimizing the average temperature (Tave) of the system. The regular sinusoidal function is considered as a fin profile, and the design variables are amplitude, A, and angular frequency, ω.
In chapter three, the deformed sinusoidal function is adopted on WPFHS. According to literature [2], the changeable sine curve with increasing amplitude and decreasing wavelength simultaneously can enhance the performance of heat sink. In this thesis, the weighting coefficients of amplitude, a, and angular frequency, b, are considered as the design variables for minimizing the average temperature of base plate (Tb).
The results shows that the wavy-shaped design can remarkably enhanced the performance of fin temperature. Finally, experimental results of WPFHS shows the conformity with the numerical data. Also, the temperature distributions between experimental and numerical results are in an excellent consistency. The inverse problems utilizing the Levenberg-Marquardt Method (LMM) can estimate the optimal fin shape successfully and efficiently.

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