Influence of the air-exposed active electrode shape on the electrical, optical and mechanical characteristics of a surface dielectric barrier discharge plasma actuator

The influence of the air-exposed active electrode shape on the electrical, optical and mechanical behaviors of a surface DBD plasma actuator is investigated. For high voltage up to 24 kV, a first set of experiments highlights that the discharge current, the plasma morphology and the produced ionic wind are fully different, according to the active electrode shape. With a wire active electrode, the discharge is streamer-free, the ionic wind velocity is improved and more homogeneous along the active electrode compared to the typical baseline plate-to-plate surface DBD. On the contrary, with a sawtooth active electrode, the streamers are more intense and the velocity is higher in front of the tips and smaller between two successive tips, following the shape of the electrode edge. Finally, by increasing the high voltage up to 30 kV, maximum ionic velocities of 7.1 m/s and 8.65 m/s are reported, with a plate active electrode and a sawtooth one, respectively. To our knowledge, these are the highest ionic wind velocities that have never been measured with a single surface DBD based on two electrodes.