Flow acceleration in an electrohydrodynamic (EHD) duct using paraelectric and peristaltic effects of a one atmosphere uniform glow discharge plasma

Abstract

Summary form only given. The plasma generated by a one atmosphere uniform glow discharge plasma (OAUGDP/sup /spl trade//) can be used in aerodynamics for boundary layer flow control, flow re-attachment and flow acceleration. Flow acceleration by an EHD duct can be based on paraelectric effects, in which plasma is accelerated by electric field gradients, and by peristaltic effects, in which the plasma is accelerated by a traveling electrostatic wave, or by a combination of these two mechanisms. In all cases, Lorentzian momentum transport by the plasma ions accelerates the neutral gas flow. Aerodynamic research with paraelectric plasma actuators currently uses a two-dimensional thin plasma layer formed by one or more sets of electrode strips. In this paper, we are conducting experiments to generate a three-dimensional EHD duct using paraelectric or combinations of paraelectric and peristaltic plasma actuators. These EHD duct configurations generate a higher electron and ion number density over a larger volume (as compared to the flat panel plasma actuators), thus transferring more momentum to the neutral gas. This improved momentum transfer accelerates the gas to higher velocities than a flat paraelectric panel. By using two RF power supplies operating at different frequencies, the paraelectrically induced flow velocity can reach more than 9 m/s. Addition of momentum by a peristaltic traveling wave increases the flow velocity still further. The performance of a three-dimensional EHD duct air flow accelerator makes it appealing for several aerodynamic applications.