Time-resolved tomographic measurements of temperatures in a thermal plasma jet

Temperatures in a thermal plasma jet were measured using an experimental set-up providing time-resolved scans of plasma optical radiation near 650 nm from four directions. The acquired data were used for reconstructions of time-resolved temperature distributions in measurement planes perpendicular to the plasma jet axis. The plasma torch was fed by the dc power source with a substantial ripple voltage modulation which leads to significant differences between the temperature distributions according to the actual phase of the arc current.