Effects of the transverse electric field on nanosecond pulsed dielectric barrier discharge in atmospheric airflow

In this paper, an asymmetric electrode geometry (the misalignment between the ends of high-voltage and grounded electrodes) is proposed in order to investigate the effects of the transverse electric field on nanosecond pulsed dielectric barrier discharge (DBD). The results show that diffuse discharge manifests in the misaligned region and the micro-discharge channel in the aligned region moves directionally. Moreover, the diffuse discharge area increases with the decrease of the discharge gap and pulse repetition frequency, which is consistent with the variation of the moving velocity of the micro-discharge channel. When airflow is introduced into the discharge gap in the same direction as the transverse electric field, the dense filamentary discharge region at the airflow inlet of asymmetric electrode geometry is larger than that of symmetric electrode geometry. However, when the direction of the airflow is opposite to that of the transverse electric field, the dense filamentary discharge region of asymmetric electrode geometry is reduced. The above phenomena are mainly attributed to the redistribution of the space charges induced by the transverse electric field.