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The possibility of controlling the aerodynamic characteristics of airfoils in transonic flight regimes by means of local pulsed periodic energy supply is considered. The numerical solution of two-dimensional unsteady equations of gas dynamics allowed determining the changes in the flow structure near a symmetric airfoil and its aerodynamic characteristics depending on the magnitude of energy in the case of its asymmetric (with respect to the airfoil ) supply. The results obtained are compared with the calculated data for the flow around the airfoil at different angles of attack without energy supply. With the use of energy supply, a prescribed lift force can be obtained with a substantially lower wave drag of the airfoil, as compared with the flow around the airfoil at an angle of attack.Introduction. The study of transonic flow around airfoils with pulsed periodic energy supply [1-4] provided the first results on nonlinear effects arising if the energy is supplied in thin zones located along the airfoil. The energy-supply regime proposed in [1-4] made it possible to reduce the wave drag of the airfoil by more than a factor of 2. Such a significant change in the flow structure with moderate consumption of energy was previously observed for supersonic flows only.The energy can be supplied along the airfoil contour, for instance, with the use of a sliding pulsed arc discharge. The corresponding experiments with Mach numbers 1.7 < M < 3.4 were performed in [5]. The experiments described in [6] involved a glow discharge on the wing of an aerodynamic model in a subsonic flow (with a flow velocity of 150 m/sec). In [7], similar experiments were performed at M = 4. Based on a plasma sheet in a transonic flow with a shock wave, a near-surface distributed energy-supply zone was obtained in [8].In the present work, the calculations were performed for asymmetric energy supply, which allowed us to obtain the lift force and pitching moment. This paper continues the investigations of the shock-wave structure of the transonic flow around a symmetric airfoil [1-4, 9, 10]. Asymmetric energy supply in a supersonic flow was considered, for instance, in [11][12][13][14].Formulation of the Problem. A system of two-dimensional unsteady equations of gas dynamics (Euler equations) in conservative form for an ideal gas with a constant ratio of specific heats γ is used as a mathematical model of the flow. A total variation diminishing (TVD) scheme is used in the intervals between instances of energy supply to solve this system numerically. Integration in time is performed by the Runge-Kutta method. The 352 × 320 computational grid in the physical domain is geometrically adapted to the airfoil contour and is refined in the vicinity of the latter. In the model considered, pulsed supply of energy is performed instantaneously, and the gas density and velocity remain unchanged thereby. The energy density of the gas e in energy-supply zones increases by Δe = ΔE/ΔS (ΔE is the total energy supplied in one zone per unit length in the direction per...

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