本論文利用商業套裝軟體CFD-ACE+建立三角翼渦流產生器之三維模型，並透過拉凡格氏法(Levenberg-Marquardt Method)最佳化渦流產生器之外形參數，以提升熱交換器之效率為目的來反算出三角翼渦流產生器最佳化之形狀。
本研究以文獻[1]為設計基礎並將其延伸，探討三種不同參數設計，並使用反算設計問題預測最佳渦流產生器外形參數。案例一將渦流產生器之長度固定，預測寬度及仰角，並與文獻[1]之結論相比，探討其外形改變對效率影響之趨勢；案例二將渦流產生器之長度、寬度及仰角皆列為預測參數；案例三以案例二之最佳化結果為初始設計，將各組渦流產生器之仰角列為參數，探討其各組參數改變對效率之影響，以上案例設計目標皆為取得熱交換器之最大效率。
由統計分析的結果顯示，經過最佳化設計後之熱交換器與無放置渦流產生器之熱交換器相比，其平均紐賽數增加了322%，最大效率達到1.34，因此達到本文之雙管型熱交換器之三角翼渦流產生器最佳化設計的目標。

A three-dimensional design problem is carried out to study the thermal-hydraulic characteristic of a heat exchanger with the delta winglet vortex generator. The objective of this thesis is to utilize the commercial package CFD-ACE+ and the Levenberg-Marquardt Method (LMM). Results show that the width of the delta- wing(w), height-pitch ratio (c/P) and the angle of attack (α) remains critical. Therefore, those parameters are chosen as our variables.
The thesis is aimed to improve the thermal performance of heat exchanger among the identical flow condition. Case A is optimized based on the original design while the width of the delta-wing and the angle of attack as design variables. Case B is optimized based on the original design while the width of the delta-wing, height-pitch ratio and the angle of attack are considered as design variables. Case C is optimized based on Case B while the angle of each vortex generators are considered as design variables.
The results of statistical analysis indicates that the optimized designs of the heat exchanger compare to the design without vortex generator, the average Nusselt number is higher by 322% and the thermal performance factor reach 1.34. As a result, the performance of heat exchanger is obviously improved.

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