Glow Discharge in an Axially Symmetric Supersonic Gas Flow

Abstract: A glow discharge in a supersonic gas flow between the central body (cathode) and nozzle (anode) has been theoretically investigated. Features of a glow discharge in a supersonic gas flow have been taken into account in the theoretical model and distributions of the internal characteristics of the discharge along the electric field lines and along the flow have been calculated. It has been found that the characteristics of the discharge in the spatial localization, radiation intensity, and formation of near-electrode zones depend on the current and geometric parameters of the nozzle and central body. The distribution of the main parameters of the discharge is affected by features of the discharge region geometry. Near the cathode, the field is strong and electrons intensively multiply. Then, the field is almost zero and electrons and ions accumulate in a cloud of electrons and ions. The electrodes absorb this electron and ion cloud. In the distributions, the Faraday dark space can be clearly seen. It extends almost to the anode. The discharge of this type can be used to produce hydrogen by direct pumping of methane through the supersonic nozzle with the central body. Each hydrocarbon molecule will be bombarded by electrons, which will result in decomposition of methane into hydrogen and carbon. The high flow rates and low temperatures will facilitate the long-term operation of the device.