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The influence of the creeping discharge on the air flow in the boundary layer and the adjoining region of a plate with a cylindrical wedge has been investigated experimentally. Experiments were carried out in a supersonic wind tunnel at a Mach number M = 3.0. The processes of initiation and propagation of such a discharge and boundary layer development on the above objects under the action of this discharge have been investigated. The data on the flow around a wedge-shape projection on the plate are presented. Introduction.In the 1950s, investigations on the heat input to the outer surface of a body around which a high-speed air stream flows began to be developed. In [1,2], on the basis of a series of calculations of the turbulent boundary layer it was shown that the surface friction of a body can be decreased by means of volume heat input into a supersonic boundary layer. At the same time, cooling of a streamlined surface can cause partial relaminarization of the flow in the turbulent boundary layer and a decrease in the friction. The possibility of decreasing the surface friction by means of volume heat input into a supersonic boundary layer at transonic flow velocities was also considered in [3]. In [4], the flow around the NASA-0012 airfoil in the range of Mach numbers M = 0.8-0.9 was investigated. The distribution of the gas-dynamic parameters over the airfoil surface located in a local supersonic zone at various values of the Mach number was obtained. It was shown that upon power input to the airfoil its drag can both increase and decrease depending on the Mach number of the undisturbed flow. The influence of the energy input to the airfoil on its lifting force, the pitching moment, and the position of the center of pressure of the airfoil was also investigated. Experiments performed in [5] showed that there is a relationship between the structure of the discharge in the boundary layer between the airfoil and the air flow and the vortex pattern of this flow. Data on the gas temperature depending on the experimental conditions are presented. In [6], the energy input to a supersonic air flow with the aim of increasing its mass at the inlet to the air intake of the scramjet at Mach numbers below the design value was investigated. The heated region creates a "virtual nozzle" and, diverting the flow, rationalizes the inlet. In this case, the region of energy input is located closer to the point of intersection of the nose shock with the extension of the nozzle line.The results of theoretical and experimental investigations on the action of electric discharges on the supersonic air flow are presented in [7]. The aerodynamic control of a symmetric cone by means of plasma discharges was investigated in [8] at M = 3; heat input to the flow in a wind tunnel was realized by means of microwave controlled discharges. In [9], an analysis was performed of the plasma methods for controlling the flow at the inlet to scramjets on the basis of the solution of two-dimensional inviscid steady-state equations jointly with equati...

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