Development of disturbances generated by an electric discharge in the shock wave / boundary layer interaction zone

The paper presents the results of experimental study of disturbances generated by an electric discharge. Observations are carried out in the zone of interaction of a shock wave and a boundary layer (the incident shock wave has the Mach number M = 1.43). Experiments were carried out in a supersonic wind tunnel with the unit Reynolds number Re1 = 11·106 1/m. The flow velocity was measured using the PIV method and hot-wire method. The artificial disturbances are generated by a periodic pulsed electric discharge; the discharge is allocated at the model surface upstream of the interaction zone. The discharge time is less than 100 ns: this enables creating a broadband disturbance inside the boundary layer. The method of phase-locked measurement with the ensemble averaging of realizations produces the spatial and temporal characteristics of disturbances generated in the interaction zone. The major growth of initial disturbances occurs in the shear layer behind the shock wave/boundary layer interaction zone (here the flow becomes turbulent).