Numerical experiments on aerodynamic resonance in transonic airfoil flow

Kurzfassung

We present the results of 2-d URANS simulations of unsteady shock/-boundary layer interaction on a supercritical airfoil in transonic flow. At constant Mach and Reynolds number the angle of attack is gradually increased until self-sustained periodic shock buffet oscillations set in. Subsequently, we focus on the subcritical flow field dynamics below the identified shock buffet onset, where already damped flow oscillations can be observed. Therefore, various fixed-point stable flows are perturbed with small time-periodic deflections of the airfoil geometry or random impulses, after which the particular flow response is analyzed in the frequency domain to identify the dominant aerodynamic eigenvalue. Furthermore, we demonstrate an effective stabilization of sub- and supercritical shock buffet flows by means of a closed-loop controller.