Active Control of Flow around NACA 0015 Airfoil by Using DBD Plasma Actuator

Abstract

Abstract. 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°, 5°, 10°, 15° and 20°. The results indicate that up to the 15° 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.

Vortex shedding noise reduction by single dielectric barrier discharge plasma actuators

“…The tones are also observed to slightly shift to a higher frequency. This is possibly an indication that the induced plasma jet has reduced the length scale of the vortex wake structure 11 . The effectiveness of the plasma actuator PA1 was explored at higher velocities.…”

“…The Dielectric Barrier Discharge (DBD) plasma actuator is simple, robust, lightweight, high frequency response and low-power consumption in the unsteady operation mode. It has been demonstrated in many studies that placing single or multiple DBD plasma actuators close to the separation point of an airfoil can prevent the flow separation and increase the lift coefficient 10,11 . Post and Corke 10 show that the plasma actuator can also prevent flow separation and the formation of dynamic stall vortex for an oscillating airfoil.…”

Aerodynamic and energy‐efficiency‐based assessment of plasma actuator's position on a NACA0015 airfoil

“…They mentioned that plasma preserve the flow direction and also stabilize the flow structure. Akansu et al [22] reports the comparison between duty cycle (10-90%) and steady actuation, revealing that duty cycle is better in increasing lift coefficient of the NACA0015 airfoil (about 25% more). Also, Font and Morgan [18] mentioned that plasma actuators are useful devices for flow control by the help of boundary layer attachment.…”

“…It is also reported that the duty-cycle-based approach leads to a significant reduction in the power consumption of the plasma actuators. Akansu et al [22] reports the comparison between duty cycle (10-90%) and steady actuation, revealing that duty cycle is better in increasing lift coefficient of the NACA0015 airfoil (about 25% more). Also, using duty cycle approach on activation of the plasma actuators have been reported to have consumed less power.…”

Bi̇r Kanat Profi̇li̇ Ve Bi̇r Dai̇resel Si̇li̇ndi̇r Etrafindaki̇ Akişin Aerodi̇nami̇k Karakteri̇skti̇kleri̇

“…Airfoil, as a streamlined or aerodynamic body, has also been used as a basic geometry in aerodynamics and hydrodynamics. Flow control around streamlined body by using a flap [9], dielectric barrier discharge (DBD) actuator [10] synthetic jet actuator [11] and so forth can be given as literature examples.…”