Spatiotemporal analysis of streamer discharge in a wire-to-wire reactor with positive nanosecond pulse supply

Abstract

The spatial and temporal distribution of the discharge streamers in positive pulsed wire-to-wire electrode configuration in atmospheric air is investigated by an electrical-optical diagnostic system. Time-resolved ICCD images show that the discharge streamers in wire-to-wire electrode develop in three phases: the primary streamer, the secondary positive streamer, and the secondary negative streamer. It is observed that the evolution of discharge streamers is strongly influenced by the amplitude of the applied voltage. The optical emission spectroscopy measurement of hydroxyl radical OH indicates that the OH is mainly generated in the secondary positive streamer near the anode region. But in the region near the cathode the emission of OH radicals can also be detected due to the secondary negative streamer. The influences of rise time, fall time and pulse duration on streamer dynamics and the subsequent radical production are observed. It is shown that the average propagation velocity of the primary streamer decreases with the increase of the rise time, while the variation of pulse width and pulse duration parameters have little effect on that of the primary streamer. The response surface methodology based on Box–Behnken design model is implemented to evaluate the contribution of the three critical pulse parameters on ozone production. The results of the response surface quadratic model show that the pulse rise time plays the most prominent role in the generation of ozone among the three pulse parameters of rise time, fall time and pulse duration.

Physical and chemical properties of a magnetic-assisted DC superimposed nanosecond-pulsed streamer discharge plasma

“…As a result, the PS head developed near the ground electrode appears as an 'intense flash' phenomenon. Similar phenomena have also been reported for other electrode geometries [37,38]. Comparison of the streamer images for different U DC indicates that the streamer luminous intensity is enhanced and the number of streamer channels is increased by enhancing the amplitude of the DC component superimposed on pulsed voltage, especially for the SS.…”

The heat dissipation by the multi-needle electrode structure ionic wind generator

“…However, during ionic wind generation, the ionization process consumes most of the electric energy and only a few percent of the electric energy is converted to the fluid energy [16]. The low ionization degree of corona and dielectric barrier discharges (10 −4 -10 −6 ) at atmospheric pressure would also result in the low wind velocity generated by the momentum transfer between charged particles and neutral molecules [17]. Therefore, the low energy efficiency and wind velocity are the most important limitations for the practical application of ionic wind cooling technique.…”