Two-dimensional simulation of an atmospheric-pressure RF DBD in a H2 : O2 mixture: discharge structures and plasma chemistry

Abstract

The results of two-dimensional modelling of a radio-frequency dielectric barrier discharge (RF DBD) in a hydrogen–oxygen stoichiometric mixture under atmospheric pressure are presented. The production of active species and the possibility of ignition of the mixture are studied. It is shown that the production of active species in the discharge is enough to reduce the ignition temperature significantly. A detailed description of the ion production and loss is presented. The processes of electron attachment are very fast, while the detachment processes depend on the type of ion. The electron detachment, charge recombination, and conversion of negative and positive ions are very important here. The current discharge consists of breakdowns that occur in each half-period, and it resembles the standard DBDs of kilohertz frequency. The surface charge is not uniform over the electrode area and the RF DBD consists of micro-discharges, which are not so pronounced as in the DBDs of kilohertz frequency. Two additional types of RF DBDs, the dual-frequency RF DBD and frequency-modulated RF DBD, are simulated for the purpose of controlling the ratio between the input power absorbed by electrons and ions in this discharge.