本論文以散熱鰭片上安裝穿孔之三角翼渦流產生器為研究基礎，利用商業套裝軟體CFD-ACE+建立散熱鰭片及渦流產生器模型，並透過拉凡格式法(Levenberg-Marquardt Method)最佳化渦流產生器之最佳穿孔直徑與擺放位置，期望在控制穿孔直徑與擺放位置之下，得到最低之底板平均溫度。
本研究分別使用柱型與平板型散熱鰭片作為設計模型，並設計穿孔之三角翼渦流產生器安裝在鰭片兩側，使用反算設計問題預測最佳參數，分析不同鰭片與不同入口速度下渦流產生器最佳化結果。Design A為柱型散熱鰭片並搭配入口速度為Re = 10000 (1.2 m/s)、Re = 15000 (1.8 m/s)、Re = 20000 (2.4 m/s)，Design B為平板型散熱鰭片並搭配入口速度為Re = 10000 (1.2 m/s)、Re = 15000 (1.8 m/s)、Re = 20000 (2.4 m/s)。兩種案例都在鰭片兩側加裝穿孔之渦流產生器，以降低散熱鰭片之底板平均溫度為目標，並求得在不同案例之下的穿孔直徑與擺放位置。
分析之後最終結果顯示，散熱鰭片的底板平均溫度在最佳化之後的確能夠降低，柱型鰭片在Re = 10000、15000及20000之三種不同入口速度之下，使用最佳設計之渦流產生器可比有放置渦流產生器且無穿孔的底板平均溫度，降低約11.2%、6.9% 及5.0%；平板型鰭片在三種不同入口速度之下，使用最佳設計之渦流產生器比有放置渦流產生器且無穿孔的底板平均溫度，可降低約12.6%、2.5%及2.0%。吾人同時也探討在兩種案例之下，有放置且無穿孔之VG與最佳設計之VG比較熱性能係數(Thermal performance factor)的差異，在Design A的案例之下，分別提升約28%、28%及26%，在Design B的案例之下，分別提升約22%、5%及16%，結果顯示在經由穿孔及位置設計之後，其底板均溫與熱性能係數改善效果顯著。
最後本研究對兩種案例進行實驗，使用紅外線熱像儀與壓差計測量實體散熱模型的溫度及壓力，並且與CFD-ACE+ 模擬計算的鰭片溫度進行交叉比對，能夠證明模擬結果與實驗結果相當一致，因此可證明本研究之可信度。

An optimal design problem for estimating the design variables of a delta winglet vortex generator (VG), i.e., its position, attack angle and perforated radius, was investigated in this work to enhance the heat dissipation performance of pin-fin and plate-fin heat sinks using the commercial code CFD-ACE+ and the Levenberg-Marquardt Method (LMM). The role of VGs is to restructure the flow pattern of the inlet air and thus to enhance cooling. Three inlet air velocities with Reynolds numbers Re = 10000, 15000 and 20000 were considered, and the optimization algorithm with LMM was chosen to estimate the optimal design variables of the VGs to yield the minimum bottom average temperature of the heat sinks. The results revealed that the gap between the VG and the heat sink (i.e., position), attack angle and the perforated radius of the VG all became larger as Re increased to improve the cooling ability of the heat sinks. In addition, the pressure drop of the heat sink can be significantly reduced due to the perforation of the VGs; as a result, the thermal performance factor of the heat sink is significantly improved. Finally, the designed optimal VGs were installed on both pin-fin and plate-fin heat sinks, and experimental verifications were conducted. The results indicated that the measured temperatures on the bottom plate of the heat sinks are very close to the computed temperatures. In addition, the base plate temperatures of the heat sink using the designed optimal VGs are always lower than those using the original design VGs for various Re, which implies that the heat dissipation performance of the heat sink using optimal VGs is enhanced.

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