本研究探討使用SU2進行流場的預測和飛機的優化模擬，將結果和Fluent計算結果與實驗數據進行比對。讓飛機在相同升力係數(C_L)下所產生的阻力係數(C_(D ))減少進而提高所帶來的經濟效益，減少環境的污染與飛行時所產生的燃油消耗。本研究使用商業套裝軟體ANSYS Fluent進行DLR-F6外型的外部流場數值模擬與網格的建造，首先網格採用混合非結構型網格，於物體表面周圍建立菱柱型網格(Prism Mesh)來模擬邊界層附近的黏性流場，其他外圍計算領域則使用四面體網格(Tetrahedron Mesh)，將模擬結果的升力係數(C_L)與阻力係數(C_(D ))與開源軟件SU2計算結果進行比對，接著使用SU2自帶的優化工具，伴隨算子(adjoint operator)對其外型進行優化設計。流場計算使用可壓縮流Reynolds-averged Navier-Stokes quations(RANS)對DLR-F6進行流場的預測，在紊流模擬上使用SST(Shear-Stress Transport)k-ω model剪應力傳輸紊流模型，透過改變飛機的外型使DLR-F6的空氣動力特性比原始外型佳。綜合上述，本文證明了SU2在全機流場模擬與優化中之可行性和準確性，可為航天工程設計與優化提供了一種有效的工具。

This study discusses the prediction of the flow field and the shape optimization of the whole aircraft machine using SU2 and compares the results with the Fluent calculation results and the experimental data. The drag coefficient(C_(D )) produced by the aircraft under the same lift coefficient (C_L) is reduced to improve the aerodynamic performance and reduce environmental pollution and fuel consumption during flight. The commercial package software ANSYS Fluent is also used to carry out the numerical simulation of the external flow field of the aerodynamic shape of DLR-F6 and the construction of the grid. First, the grid adopts a mixed unstructured type, and a prismatic grid is established around the surface of the object to simulate the viscous flow field near the boundary layer, other peripheral computing fields use tetrahedron mesh, and the lift coefficient (C_L) and drag coefficient (C_(D )) of the simulation results are calculated with the open source software SU2. Then use the optimization tool that comes with SU2 to optimize its appearance.

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