Study on multi-peak behavior of pulsed dielectric barrier discharges in atmospheric-pressure helium

In this work the multi-peak behavior of the dielectric barrier discharge excited by repetitive voltage pulses (pulsed DBD) in atmospheric-pressure helium has been systematically investigated, based on a one-dimensional fluid model. The effects of the parameters of the applied voltage pulse and dielectrics on the multi-peak behavior of the pulsed DBD have been analyzed in detail. The parameters of the applied voltage pulse include voltage growth rate, amplitude, pulse-width, and frequency. The parameters of dielectrics refer to relative permittivity and dielectric thickness. Under the given amplitude of the applied voltage pulse, the number of current pulses presents no monotonic decrease with increasing voltage growth rate, and the dependence of the amplitude of each current pulse on voltage growth rate is different. For a given voltage growth rate, the number of current pulses will increase with increasing applied voltage amplitude, but the amplitude of each current pulse does not vary. In addition, the increase of the pulse-width or the frequency can induce not only later appearance of current pulses and smaller amplitude of the last current pulse at the rising edge of the applied voltage pulse but also larger amplitude of the last current pulse at the falling edge of the applied voltage pulse. Also, the decrease of relative permittivity of the dielectric or the increase of dielectric thickness results in smaller discharge current density and shorter time of charging dielectrics, which may increase the number of current pulses.