Stall control at high angle of attack with plasma sheet actuators. Experiments in Fluids 42

We analyze the modifications of the flow around a NACA 0015 airfoil when the flow is periodically perturbed with an electrohydrodynamic (EHD) actuator. The device used consists of two bare electrodes flush mounted on the surface of the profile operated in a discharge regime characterized by the formation of a plasma sheet contouring the body. In this study, we analyze the influence of the frequency of a periodic actuation on the aerodynamic performance of the airfoil. The analysis is undertaken with measurements of the surface pressure distribution and of the flow fields with Particle Image Velocimetry technique. The experiments indicate that at moderate Reynolds numbers (150.000 < Re < 333.000), the actuation enables a reattachment of the flow at high values of the angle of attack (α>15°)