Main field of study: 011200 Physics
Area of specialization: 20 Physical Optics and Lasers
Department of Optics
Scientific advisor: Associate professor A.A. Kudryavtsev
Reviewer: Associate professor Yu.E. Skoblo

Modelling of DC glow discharge in argon: analysis of discharge characteristics and investigation of its structure
M.I. Zakharov 

The hybrid two-dimensional numerical model of a glow discharge in argon was developed. The core of model formed by the system of hydrodynamic equations of particle balance, electron energy balance and the Poisson equation. At some conditions heat balance equation added to the model in case of gas heating accounting necessity. Due to analysis of electron kinetics increased accuracy of simulation achieved. For this purpose the reaction rate constants Ki, electron mobility μe and the diffusion coefficient De computed by solving Boltzmann kinetic equation. Considered two sets of plasma-chemical reactions: for low pressure P ~ 1 Torr and for a pressure of about atmospheric. Via the model current-voltage characteristics and spatial distribution of the main parameters of the discharge was obtained. The results are compared with the references, shows good agreement. Comparison of discharges scaled by a factor of λ = 100 is made for low and atmospheric pressure in normal and abnormal mode. The influence of various elementary reactions occurring in the discharge, to violation of scaling laws was investigated. The contribution of gas heating to the steady state characteristics of short discharge in argon at atmospheric pressure was estimated. It is demonstrated that a sharp rise in CVC already occurred in the normal discharge. It is proved that the displacement of the gas from discharge gap caused by the temperature increasing leads to obstructed discharge mode.