Operating regimes and structure of an atmospheric-pressure interelectrode microwave discharge in argon

Continuous and pulse-periodic operating regimes and spatio-temporal structure of an atmospheric-pressure interelectrode microwave discharge in transverse argon flow were experimentally investigated for a hemisphere-to-plate electrodes configuration. A multielectrode plasma torch with a power of about 100 W was used as a gas-discharge device, electromagnetic energy to which was supplied from a waveguide-type microwave plasma torch operating on the basis of a magnetron with a frequency of 2.45 GHz. The discharge regime switching were carried out using a high-voltage three-phase magnetron power supply. In the continuous regime, fractal filamentation of near-electrode regions of a glow-type microwave discharge was described. Diagnostics of the regimes was conducted by floating potential oscillography of the microwave discharge flowing afterglow (cold plasma jet).