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10th Anniversary International Conference on Experimental Fluid Mechanics -- NOV 17-20, 2015 -- Prague, CZECH REPUBLIC, WOS: 000400395300106, A promising novel actuator called Spark-Plug Plasma Synthetic Jet (SPSJ) has been developed in Atmospheric Plasma Research Laboratory at Nigde University. It generates electrothermally high synthetic jet velocity by using high voltage. SPSJ actuator can be utilized to be an active flow control device having some advantages such as no moving parts, low energy consumption and easy to integrate the system. This actuator consists of two main components: semi-surface spark plug (NGK BUHW) as an anode electrode and a cap having an orifice as a cathode electrode. The cap, having a jet exit orifice diameter of 2 mm, has diameter of 4.4 mm and height of 4.65 mm. This study presents the characteristics of SPSJ actuator by using the hot wire anemometer in order to approximately determine jet velocity in quiescent air. Peak velocity as high as 180 m/s was obtained for f(e) = 100 and duty cycle 50%. The flow visualization indicated that the actuator's jet velocity is enough to penetrate the developed boundary layer., DANTEC Dynam GmbH, LAVISION, LENAM, MECAS ESI s r o, MIT s r o, TSI GmbH, Scientific and Technological Research Council of Turkey (TUBITAK) [213M179], The authors would like to acknowledge the financial support of this work by the Scientific and Technological Research Council of Turkey (TUBITAK) under the Contract Number of 213M179.

7th International Conference on Experimental Fluid Mechanics (EFM) -- NOV 20-23, 2012 -- Tech Univ Liberec (TU Liberec), Hradec Kralove, CZECH REPUBLIC, WOS: 000319932200008, In this study, effect of plasma actuator on a flat plate and manipulation of flow separation on NACA0015 airfoil with plasma actuator at low Reynolds numbers were experimentally investigated. In the first section of the study, plasma actuator which consists of positive and grounded electrode couple and dielectric layer, located on a flat plate was actuated at different frequencies and peak to peak voltages in range of 3-5 kHz and 6-12 kV respectively. The induced air flow velocity on the surface of flat plate was measured by pitot tube at different locations behind the actuator. The influence of dielectric thickness and unsteady actuation with duty cycle was also examined. In the second section, the effect of plasma actuator on NACA0015 airfoil was studied at Reynolds number 15000 and 30000. Four plasma actuators were placed at x/C = 0.1, 0.3, 0.5 and 0.9, and different electrode combinations were activated by sinusoidal signal. Flow visualizations were done when the attack angles were 0 degrees, 5 degrees, 10 degrees, 15 degrees and 20 degrees. The results indicate that up to the 15 degrees attack angle, the separated flow was reattached by plasma actuator at 12kV peak to peak voltage and 4 kHz frequency. However, 12 kV(pp) voltage was insufficient to reattach the flow at 20 angle of attack. The separated flow could be reattached by increasing the voltage up to 13 kV. Lift coefficient was also increased by the manipulated flow over the airfoil. Results showed that even high attack angles, the actuators can control the flow separation and prevent the airfoil from stall at low Reynolds numbers., Dantec Dynam GmbH, Kamax Holding, LENAM s r o, MIT s r o, SPECION s r o, Scientific and Technological Research Council of Turkey (TUBITAK) [110M056], The authors would like to acknowledge the financial support of this work by the Scientific and Technological Research Council of Turkey (TUBITAK) under the Contract Number of 110M056.