Diagnostics of argon plasma immersed into water and produced by a non-transferred ARC by optical emission spectroscopy

Optical emission spectroscopy techniques based on evaluation of the plasma emission coefficients have been adopted for the measurements of plasma parameters of ARCs immersed into water and for determining potential active species and their distribution in the plasma. An electric ARC torch in argon has been considered working in non-transferred mode to produce the plasma. The resulting plasma jet is neither homogeneous nor stable one which makes it especially difficult for the OES measurements. So, the approach has been applied relying upon relative intensity of lines in the plasma total emission spectra and some general data on the plasma behaviour. The measurement results give a rather realistic picture of plasma parameters and spatial distributions of active species in the plasma jet with an admixture of water.