Utilization of open source software for airfoil and fighter aircraft simulations and validation with commercial software

Date: November 2018In this thesis, it is aimed to demonstrate the simulation capabilities of the open source SU2 code developed by Stanford University and the well known ANSYS Fluent on test cases with increasing complexity for aerodynamics simulations. Computational Fluid Dynamics simulations with ONERA M6, SACCON (Stability and Control Configuration) and X-31 test cases are executed for this purpose. ONERA M6 is chosen for transonic lambda shock formation, SACCON for its wing-body configuration and X-31 for being a full scale fighter aircraft. ONERA M6 case is simulated with both softwares and SA and k-ω SST turbulence models are used. It is observed that for the simulations with both softwares, k-ω SST yields more accurate results. Despite being an open source software, SU2 yields more accurate results than ANSYS Fluent on shock estimation. Low subsonic and high angle of attack simulation of SACCON is carried out with SU2. The results are consistent with test data. Especially, despite the highly vortical flow structure on the suction side, very good agreement with the test results are obtained for moment coefficients which demonstrates the reliability of the open source code. X-31 is a full scale fighter aircraft with a canard and nose, wing and tail fins. X-31 test case is simulated for low subsonic speeds and high angles of attack with ANSYS Fluent software. Considering the complexity of the flow caused by fins and canard, simulation results managed to approach the test data moreover the results show satisfactory agreement with DLR TAU open source code. Briefly, both softwares are proven for their high fidelity simulation capabilities on the given test cases. Particularly results demonstrated by the open source and absolutely free SU2 code showcases the accesibility of such complex simulations without any licence fees. Keywords: Turbulence Model, Spalart Allmaras, K-ω Shear Stress Transport, Open Source, ANSYS Fluent, SU2