Influence of the charges deposition on the spatio-temporal self-organization of streamers in a DBD

At atmospheric pressure, dielectric barrier discharges (DBDs) are mainly constituted of unstably triggered non-equilibrium transient plasma filaments, also called microdischarges. A self-organization of plasma filaments and their interaction with the deposited charges upon the dielectric material has been studied previously for frequencies on the order of a few kilohertz (for example see Guikema et al (2000 Phys. Rev. Lett. 85 3817) and Chirokov et al (2004 Plasma Sources Sci. Technol. 13 623–35)). In this paper we realized a DBD in the configuration cylinder-tip to dielectric plate biased by a low frequency power supply (50 Hz) in synthetic air. Using a CCD camera coupled with electrical diagnostics we observed collective behaviour of plasma filaments in the gas gap, as already observed for asymmetric surface dielectric barrier discharges (ASDBD) in Allegraud et al (2007 J. Phys. D: Appl. Phys. 40 7698–706) and predicted in Guaitella et al (2006 J. Phys. D: Appl. Phys. 39 2964–72). We also show how the surface charge deposited upon the dielectric plate modifies the spatial organization of microdischarges in this experimental device. In parallel, we made an electrostatic model of the experimental device which gave results consistent with the experimental measurements and with the assumption we made on the role of the deposited charges for their impact on the subsequent discharges during a positive half-cycle.