Experimental study of transient processes in a Glow Discharge

Abstract

The article experimentally investigated the features of a glow discharge with a hollow cathode in a longitudinal air flow. The discharge chamber consisted of glass sections separated by copper plates serving as probes. The channel formed by such sections and probes had a cylindrical shape. Air flowed through the hollow cathode into the cylindrical channel. The anode served as a metal grid. Probes and electrodes were made of copper. The distance between the electrodes was 6.5 cm. The air pressure P, its speed V, the discharge current I and its voltage U changed respectively in the ranges: P = (6, 4 - 19) kPa, V = (0 - 10) m / c, I = (5-100) mA, U = (1, 0 - 2, 2, 0) kV. Volt-ampere characteristic had negative differential resistance. It was found that in the range of discharge currents I = (40-80) mA, the forward and reverse branches of the current-voltage characteristics do not match. When the current decreases (reverse branch), the discharge voltage rises sharply. This is due to the process of transition of a glow discharge into its non-stationary form, which was observed visually and was recorded photographically for all the characteristic modes of discharge. It was also shown that the flow of air allows a reverse transition to the usual form of discharge.