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The article is devoted to an experimental study of the features of the combustion of a glow discharge between a hollow copper cathode and a mesh anode in a longitudinal air flow. The cylindrical channel of the discharge chamber was formed by five glass sections separated by copper plates, which served as probes for measuring the plasma potential. Air flowed through the hollow cathode into a cylindrical channel. The anode was a metal grid of a copper plate 1.5 mm thick with holes uniformly located on it with a diameter of 1 mm. The distance between the hollow cathode and the mesh anode was 6.5 cm. Air pressure P, its velocity V, discharge current I and its voltage U varied respectively in the ranges: P = (6. 4 - 19) kPa, V = (0 - 10) m / s, I = (5-100) mA, U = (1. 0 – 2. 0) kV. The current-voltage characteristic had a negative differential resistance. By changing the ballast resistance, the forward and reverse branches of the current-voltage characteristic were removed. It was found that in the range of discharge currents I = (40-80) mA, these branches do not coincide, that is, hysteresis phenomena were observed. In the ascending branch of the current-voltage characteristic in the region of the current strength I = 80 mA, the discharge voltage increases sharply from U = 1. 2 kV to U = 1.6 kV. In this case, the discharge glow becomes more intense, wider and brighter, and the structure of light and dark zones along the discharge chamber also changes. Characteristic photos of the discharge are given. The formation of luminous and dark gaps inside the positive column of the discharge and their movement towards the anode was detected.

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Currently, a glow discharge is widely used not only as a gas-discharge light source or as an active medium for gas lasers, but also as an element of a plasma-chemical reactor, which allows for various chemical transformations in order to obtain new materials, modify and clean surfaces. Despite the fact that the structure and distribution of parameters in a classical glow discharge without gas flow and flat cylindrical electrodes are well known, to solve new technological problems, it is necessary to study glow discharge in discharge chambers with different electrode geometries and gas flow organization methods.The presence of a gas flow causes heterogeneity in the distribution of the parameters of a glow discharge, and can also affect the structure of its individual zones. Experimental study of the parameters of a longitudinal glow discharge will allow not only a better understanding of the physics of gas discharge, but also will make it possible to find ways to control these parameters, which is important for designing discharge chambers of various technological purposes. The article is devoted to a comprehensive experimental study of the distribution of potentials, field strength, current-voltage characteristics in a longitudinal glow discharge. The gas pressure P, its flow rate G, the discharge current strength I and its voltage U vary respectively in the ranges: P = (2–9) kPa, G = (0–0. 05) g / s, I = (30-80) mA, U = (1 - 2) kV.