Electrohydrodynamic wind generation in planar DBDs: role of electrode symmetry and geometry

Abstract This study experimentally and numerically investigates the electrohydrodynamic (EHD) interaction induced by a surface dielectric barrier discharge (SDBD) actuator at atmospheric pressure. The EHD effect, driven by non-thermal plasma in a dielectric barrier discharge (DBD), generates ionic wind, which is characterized here for a symmetric annular-type DBD actuator. A symmetric annular-type DBD actuator, consisting of concentric ring–disk electrodes that generate a predominantly vertical ionic wind rather than a tangential jet. Despite extensive studies on linear and tangential SDBD actuators, the influence of annular electrode geometry on vertically induced ionic wind and associated ozone generation remains insufficiently explored. We analyze the induced wind velocity perpendicular to the electrode plane, focusing on the influence of geometric parameters—electrode diameter (D) and thickness ( δ )—on performance. Experimental results reveal a maximum wind velocity of 3.42 m s −1 ± 1% for an optimized configuration (D = 32 mm, δ = 0.06 mm), corroborated by numerical simulations. The simulations further elucidate the velocity profile, volumetric force, electron temperature, and gas pressure distribution within the plasma region. Complementary diagnostics, including O 3 concentration measurements and Schlieren imaging, demonstrate that larger electrode diameters (e.g., 32 mm and 22 mm) enhance vertical flow height but concurrently increase ozone production. These findings provide actionable insights for designing DBD-based systems in applications such as plasma flow control, air purification, and biomedical plasma technologies.