Effect of gas flow on the form and characteristics of Glow Discharge

Abstract

The article is devoted to an experimental study of the effect of gas flow on the characteristics of a glow discharge. The design of the discharge chamber made it possible to change the interelectrode distance a = (2–8) cm. The family of current-voltage characteristics was measured in the following ranges of gas pressure P, its flow rate G, discharge current I and voltage U: P = (4. 7 - 26) kPa, G = (0 – 0.05) g / s, I = (20 - 100) mA, U = (1. 5 – 4. 2) kV. The oscillations of the discharge voltage were recorded with an oscilloscope, the current-voltage characteristic of the discharge was recorded by a two-coordinate recorder. The current-voltage characteristics had a negative differential resistance. The influence of the interelectrode distance on the type and quantitative relationships of these characteristics is analyzed. When gas is pumped through the discharge chamber, the current-voltage characteristics do not change qualitatively, but the discharge voltage and the steepness of the characteristics increase compared to a discharge without gas flow. At pressures of the order of P = 26 kPa, the discharge stability deteriorates, and high-frequency oscillations of the discharge voltage are observed in the gas flow (f ∼ 100 kHz). In this case, the discharge voltage decreases by a value of the order of tens of volts, and the glow of the positive column of discharge becomes intermittent. The typical oscillograms of discharge voltage pulsations are given.