CALCULATIONS OF A FREE-BURNING ELECTRIC ARC BY NON-EQUILIBRIUM MODEL

In order to investigate the processes in electric arc, a two-temperature approach calculation was carried. In accordance with two-temperature approach plasma of an electric arc consider as a mixture of two interacting components (the electron and atom-ion) with different temperature. Also was taken into account the deviation of plasma from ionization equilibrium. In the framework of calculation was used a model of electric arc, comprising of itself the Navier−Stoks equations, Maxwell equations, energy balance equations for electron and atom-ion plasma components, equations for determination of plasma composition and transport coefficients in non-equilibrium conditions. The calculations were conducted for arcs long L=10÷20mm burning in argon at currents I=50÷150A and gas flow rate G=20l/min. The temperature of electron and atom-ion plasma components, velocity and pressure of plasma, current density and electric field strength was obtained as a result of calculations. Also was carried an analysis of influence the deviation from thermal and ionization equilibrium to plasma composition and transport coefficients. Finally the radial and axial distribution of electron and atom ion temperature, plasma velocity and pressure, the heat flux to the anode was calculated.