Effect of external flow velocity on momentum transfer of dielectric barrier discharge plasma actuators

• Published in: Journal of applied physics Vol. 116; no. 10
• Main Authors: Pereira, Ricardo, Ragni, Daniele, Kotsonis, Marios
• Format: Journal Article
• Language: English
• Published: Melville American Institute of Physics 14.09.2014
• Subjects: Applied physics; Boundary layers; CCD cameras; Configurations; Crosstalk; Dielectric barrier discharge; Electrical measurement; Flow velocity; Light emission; Load cells; Mathematical models; Momentum transfer; Plasma actuators; Power consumption
• DOI: 10.1063/1.4894518
• ISSN: 0021-8979

An experimental study is performed towards identifying cross-talk effects between DBD plasma actuators and external flow. An actuator is positioned in a boundary layer operated in a range of free stream velocities from 0 to 60 m/s, and tested both in counter-flow and co-flow forcing configurations. Electrical measurements are used for estimating the power consumption and the discharge formation is visualized using a CCD camera. The actuator's force is measured using a sensitive load cell. Results show the power consumption is constant for different flow velocities and actuator configurations. The plasma light emission is constant for co-flow forcing but shows a trend of increasing intensity with counter-flow forcing for increasing free stream velocities. The measured force is constant for free stream velocities larger than 20 m/s, with same magnitude and opposite direction for the counter-flow and co-flow configurations. In quiescent conditions, the measured force is smaller due to the change in wall shear force by the induced wall-jet. An analytical model is presented to estimate the influence of external flow on the actuator force. It is based on conservation of momentum through the ion-neutral collisional process while including the contribution of the wall shear force. Satisfactory agreement is found between the prediction of the model and experimental data at different external flow velocities.