Active Control of Flow Separation Over a NACA0024 Airfoil by DBD Plasma Actuator and FBG Sensor

Dielectric barrier discharge plasma actuators (DBD-PA) and fiber Bragg grating flow sensors (FBG-FS) have been investigated for active control of flow separation around a NACA0024 airfoil. Tangential jets were produced in the vicinity of the DBD-PA slightly aft of the leading edge of the airfoil. The flow separation control ability was evaluated at a low Reynolds number, Re = 5.0×10⁴, in an open-circuit wind tunnel. Analysis of instantaneous and time-averaged velocity distributions around the airfoil was achieved using a particle image velocimetry (PIV) system. The flow conditions induced by the DBD-PA to suppress the flow separation were found for angles of attack of α = 8°, 12°, and 16°. When unaided by the DBD-PA system, flow separations from NACA0024 airfoil are suppressed significantly for certain Reynolds numbers and angles of attack. FBG-FS attached a chord-wise cantilever near the trailing edge of the airfoil was used to measure strain fluctuations for its feasibility to detect flow separation in real time and construct feedback control system with DBD-PA. In this study, it was found that standard deviations of strain fluctuations increase obviously in cases of flow conditions at which the flow around NACA0024 airfoil separates.