The main results of the performed theoretical and numerical studies are: The steady-state composition of plasma of single-element vapour approaches Saha-Boltzmann distribution, while substantially nonequilibrium composition can be reached in two vapours mixture. Investigations for the influence of kinetics on the temperature regime of gas-discharge plasma have confirmed that the equilibration of electronic and heavy particles temperatures occurs for a sufficiently short time (0.1 - 1 sec). This important result justifies the applicability of thermodynamic equilibrium models for the description of electric discharge in gases. The nonequilibrium composition emerges due to the presence of particles of different gases, whereas radiation transfer modelling can be performed by equilibrium approaches. Mathematical modelling of gas discharge in a wide range of pressures have shown, that the maximum degree of nonequilibrium, and subsequently maximum luminous efficiency is reached at 2-5Bar.Analysis of the starting process for gas-discharge has shown that the process rate can be increased by the introduction of "heavy" inert gas (Xe or Ar). The performed analysis of available literature has shown that small clusters formation and evolution substantially influence on physical properties of discharge plasma and operation features of discharge-based lighting devices.
The performed studies show that perspective directions of further investigations are i) analysis of new perspective cluster media and ii) increase of efficiency by means of studies of processes kinetics at equilibrium approximation.
The following software systems have been developed:
1. Simulation software for modelling of non-equilibrium discharge plasma, including calculation block, system of relational tables for kinetic coefficients, convenient interface and graphical presentation system.
2. TORATOM database software for storing of initial spectroscopic characteristics of atoms and ions: determination and processing of thermodynamic and optical characteristics of plasma formations either in conditions of local thermodynamic equilibrium (LTE) or equilibrium violation determined on self-consistent model of Hartree-Fock-Sletter.