Plasma actuators for airflow control: measurement of the non-stationary induced flow velocity

This paper deals with the measurement of the instantaneous flow velocity induced by surface plasma actuators in air at atmospheric pressure. More accurately, experiments with Laser Doppler Velocimetry (LDV) are conducted with two different types of plasma actuators in order to determine the establishment time of the induced airflow. DC corona discharges and AC dielectric barrier discharges are investigated in their non-stationary running (ignition and stop of the discharge) using a synchronization between power supplies and the LDV system. Results show: (1) The discharge-induced velocity is some m/s. (2) There is a strong correlation between the transient regime of the discharge current and the ionic wind velocity. (3) The AC discharge seems to induce a pulsed airflow at a frequency corresponding to the high voltage waveform frequency. (4) The DC discharge generates an airflow with important fluctuations which have not been correlated with current fluctuations.