Measurements of the Temperature of Subsonic CO{sub 2} Induction Plasma Flows by Analyzing Their Emission Spectra

• Published in: Plasma physics reports 2004-11, Vol.30 (11)
• Main Authors: Bykova, N.G., Kuznetsova, L.A.
• Format: Article
• Language: English
• Subjects: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ANODES; CARBON DIOXIDE; EMISSION SPECTRA; EXCITATION; EXCITED STATES; INDUCTION; MOLECULES; PLASMA; PLASMA DENSITY; PLASMA HEATING; SELF-ABSORPTION; SUBSONIC FLOW
• ISSN: 1063-780X; 1562-6938
• DOI: 10.1134/1.1825132

Results are presented from measurements of the temperature characteristics of subsonic CO{sub 2} plasma flows generated by a 100-kW induction plasmatron at the Institute for Problems of Mechanics, Russian Academy of Sciences. The atomic excitation temperature T{sub a} and the population temperature T{sub e} of the electronic states of C{sub 2} molecules (both averaged over the jet diameter) were measured from the absolute intensities of the atomic spectral lines and the spectrum of C{sub 2} molecules in different generation regimes at gas pressures of 25-140 hPa and anode supply powers of 29-72 kW. The longitudinal and radial profiles of the temperatures were determined for some of these regimes and compared to those obtained from numerical calculations of equilibrium induction plasma flows in the discharge channel. For some generation regimes, the dependences of the averaged (over the line of sight) rotational and vibrational temperatures (T{sub r} and T{sub v} ) on the discharge parameters, as well as the radial profiles of these temperatures, were determined from the best fit of the measured and calculated spectra of C{sub 2} molecules (Swan bands). The self-absorption of molecular emission was observed at sufficiently high temperatures and gas pressures, and its influence on the measured values of the molecular temperatures T{sub e} , T{sub v} , and T{sub r} was examined.