Spectroscopic Investigations of Plasma Generated by Waveguide-supplied Nozzleless Microwave Source
J. Mizeraczyk1, 2, B. Hrycak1, M. Jasiﾅгki1, and M. Dors1
1Centre for Plasma and Laser Engineering, The Szewalski Institute of Fluid Flow Machinery, Poland
2Faculty of Marine Electrical Engineering, Gdynia Maritime University, Poland
Abstract— In this paper, results of spectroscopic study of microwave (2.45 GHz) plasma at atmospheric pressure and high flow rate are presented. The plasma is generated by waveguide-supplied coaxial-line-based microwave plasma source (MPS). Pure argon, nitrogen and methane were used as working gases. An additional nitrogen flow rate of 50 l/min was introduced to the plasma by four gas ducts which formed a swirl flow inside the quartz tube. The swirl concentrated near the quartz cylinder wall, stabilized plasma generation and protects the quartz tube wall from overheating. Working gas flow rate and microwave absorbed power varied from 50 up to 200 l/min and from 600 up to 5000 W, respectively. The emission spectra in the range of 300 - 600 nm were recorded. The rotational and vibrational temperatures of N2+ ions, C2, N2, CN molecules and OH radicals were determined by comparing the measured and simulated spectra. The MPS can be used in various gas processing applications.
Keywords— Microwave plasma, OES, rotational temperature, gas processing