Characterization of a He-H₂-N₂ jet plasma by means of a plug-flow model

A global plasma kinetics model of atmospheric pressure jet plasma in He with admixture of H₂ and N₂ is taylored to a plug flow model. The composition and velocity of the feed gas as well the spatial profile of the power density are used as input parameters. The global model solves rate equations for the species occurring in the most important reactions including electron impact with heavy species and reactions between heavy species along with the energy balance of electrons and heavy species. The model involves 21 species and 120 reactions. The flow conditions in the active zone and in the effluent of the RF discharge are considered in terms of a pseudo-one-dimensional plug flow model. The latter accounts for gas expansion at constant pressure. In this way, the temporal evolution of a volume element flowing with the gas is converted into a spatial dependence of all quantities considered. The models allows one to get insight into the plasma chemistry and to study the influence of power and flow rate. Selected results are compared with experimental findings available from literature.