Analysis of Streamers in Pulsed Corona and Dielectric Barrier Discharges

In recent years, there has been a growing interest in comparative studies between a pulsed corona discharge (PCD) and dielectric barrier discharge (DBD) for the purpose of the more effective decomposition of pollutant gases, such as NOx and VOCs. In our previous NO decomposition experiment, for example, showed that the PCD was effective to decompose NO in nitrogen whereas the DBD was efficient to decompose NO in air. Since a streamer measurement by using optical emission spectroscopy revealed that the energy levels of the PCD and DBD was different, it is believed that the streamer characteristics are closely related with the efficiency of the pollutant decompositions. In this work, respective numerical analysis of the streamer in PCD and DBD are carried out for a deeper insight into the plasma induced chemical reactions. • Streamer analysis in PCD: We have developed a 3-D numerical simulation model to predict more reliable streamer propagation in a wire-cylinder reactor. As a result, inherent 3-D nature of the streamer propagation is successfully obtained. In addition, interaction phenomena between the neighboring streamers are more deeply investigated with this novel 3-D approach. • Streamer analysis in DBD: It is experimentally well known that streamers take place during the rising phase of AC voltage and they show recurrent phenomena as well. Until now, however, numerical verifications have not been found yet, so, a new approach was carried out with considering the surface charge behavior on the barrier materials. The present simulation result apparently shows the conduction loss of the surface charges is a key factor in recurrence phenomena in DBD. It is also found that a fast voltage rise produces electrons with high energies, while a slow voltage fall sustains the streamers for a longer period.