Vers la déstabilisation d'une bulle de recirculation

Abstract

We investigate the ability of a recirculation bubble to be destabilized at low Reynolds number through stationary blowing and suction at the wall. A sensitivity analysis is developped in the framework of linear global stability theory that alleviates the effect of base flow modification on the temporel growth rate of linear global modes. The base flow modifications are induced by modification of the base flow wall velocity. The most sensitive global modes are identified and their sensitivity function indicate that wall blowing and suction should be applied in the region of reattachment to be most efficiently destabilizing. It is finally suggested that such a wall control might trigger the onset of the classical vortex shedding phenomenom.