Kanat profillerinde buffet araştirmasi

The aim of the present thesis is to investigate buffet onset characteristics in two-dimensional flow. NACA0012 airfoil was chosen as the geometry in this study since the profile is frequently used for the lifting surfaces of aircraft, which are exposed to high flight loads during transonic flight and this causes buffet and flutter. In addition, it is one of the very few models which was studied for the buffet onset investigation in the literature and detailed wind tunnel test data is available. In the present study, after determining the optimum mesh resolution and the appropriate turbulence model, the results of the steady flow numerical analysis for low and high Reynolds numbers were validated with wind tunnel data. The transient flow is investigated for the buffet onset region of the NACA0012 airfoil and the results are verified with wind tunnel data. The oscillating behavior of the shock wave on the airfoil is investigated through the frequency and the Strouhal numbers of lift, drag, moment and static pressure distributions through time and frequency. The study investigates the primary effectors that stimulate buffet onset and the behavior of the flow during buffet through numerical analyses using Unsteady Reynolds-Averaged Navier-Stokes (U-RANS) Equations. The effects of Mach number, angle of attack and Reynolds number on buffet onset is investigated for the examination of buffet characteristics in detail.