Application of spring analogy mesh deformation technique in airfoil design optimization

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Tezin Türü: Yüksek Lisans

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Mühendislik Fakültesi, Havacılık ve Uzay Mühendisliği Bölümü, Türkiye

Tezin Onay Tarihi: 2015

Öğrenci: YOSHEPH YANG

Danışman: SERKAN ÖZGEN

Özet:

In this thesis, an airfoil design optimization with Computational Fluid Dynamics (CFD) analysis combined with mesh deformation method is elaborated in detail. The mesh deformation technique is conducted based on spring analogy method. Several improvements and modifications are addressed during the implementation of this method. These enhancements are made so that good quality of the mesh can still be maintained and robustness of the solution can be achieved. The capability of mesh deformation is verified by considering rotating case of an airfoil for both inviscid and viscous meshes. The edge connectivity required in the spring analogy itself is computed by several simple algorithms. It is found that the presence of modified spring analogy technique leads to better solution in mesh deformation technique. Regarding the aerodynamic design optimization, SU2 3.2.9 open source software is used as the CFD Solver. During the computation, the initial mesh used in the optimization is obtained from Pointwise® mesh generation software. OPTLIB Gradient Optimizer of Phoenix Model Center is implemented as the optimization solver. The optimization process is conducted for four different flight conditions. In each flight condition, minimizing airfoil drag becomes the objective function with different angle of attack constraints imposed. Furthermore, several shape parameterizations are utilized. It is found that in each case, optimized airfoil can be found based on the designated design variables.