In our contribution, the positive column of oxygen DC glow discharge is investigated using methods of computational physics at medium pressures (200–687 Pa) and discharge currents from 20 to 40 mA. Under mentioned conditions, the attributes of the DC oxygen discharge are particular, what is based on the existence of two forms: H‐form and T‐form. One‐dimensional fluid model of the stable H‐form has been developed. Not only radial profiles of various species in cylindrical tube but also the reaction among them and their interaction with the walls are taken into account. The model is built on the continuous description of concentration of species and drift‐diffusion approximation of the particle flux. The results of the simulation are in good agreement with experimental ones.

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The positive column of argon‐oxygen direct current (DC) glow discharge was investigated using a fluid model at pressures of around 410 Pa and discharge currents from 10 to 40 mA. The model was used to study the influence of an oxygen admixture on the properties of argon discharge. The simulated intensity of the electric field strength was compared with measured values at 5% and 100% of oxygen concentration. The one‐dimensional model in a cylindrical tube is based on the drift‐diffusion approximation of particle flux and the mean‐electron‐energy approximation is used to describe the electron interaction. The model takes into account the radial profile of particle concentration, the neutral gas kinetic temperature profile, and interactions with the wall in the cylindrical glass discharge tube. It was shown that 2% of the oxygen admixture causes a significant increase in longitudinal electric field strength and gas heating.