Simulations of Plasma Filamentation in Dielectric Barrier Discharges*

Dielectric Barrier Discharges (DBDs) are widely used in various configurations to produce cold atmospheric pressure plasmas. Depending on operating conditions, they generate transient filamentary or homogeneous discharges. The DBD can be generated between two parallel electrodes covered by dielectrics interfacing with the plasma. Dynamics of pattern formation in such a DBD configuration have been observed in many experiments and simulations. In previous work, we have simulated plasma self-organization in Helium DBD [1]. It was shown that charge accumulation on dielectric surfaces is responsible for pattern formation. The present work aims to understand the underlying physics better and clarify the mechanisms of plasma filamentation in DBDs. For our studies, we use commercial CFD-ACE+ software to analyze the influence of the gas type, pressure and composition, dielectric type (resistivity, and secondary electron emission coefficient), and driving voltage (amplitude and frequency) on the pattern formation. The results of simulations are compared with available experimental data. We clarify the effects of plasma properties and surface processes on the self-organization phenomena at the plasma interface with solid dielectrics that could be valuable for more complex geometries and operating conditions used in practical applications.