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Title: Microwave plasma source operating with atmospheric pressure air-water mixtures

Abstract

The overall performance of a surface wave driven air-water plasma source operating at atmospheric pressure and 2.45 GHz has been analyzed. A 1D model previously developed has been improved in order to describe in detail the creation and loss processes of active species of interest. This model provides a complete characterization of the axial structure of the source, including the discharge and the afterglow zones. The main electron creation channel was found to be the associative ionization process N + O {yields} NO{sup +}+ e. The NO(X) relative density in the afterglow plasma jet ranges from 1.2% to 1.6% depending on power and water percentage, according to the model predictions and the measurements. Other types of species such as NO{sub 2} and nitrous acid HNO{sub 2} have also been detected by mass and Fourier Transform Infrared spectroscopy. The relative population density of O({sup 3}P) ground state atoms increases from 8% to 10% in the discharge zone when the input microwave power increases from 200 to 400 W and the water percentage from 1% to 10%. Furthermore, high densities of O{sub 2}(a{sup 1}{Delta}{sub g}) singlet delta oxygen molecules and OH radicals (1% and 5%, respectively) can be achieved in the dischargemore » zone. In the late afterglow the O{sub 2}(a{sup 1}{Delta}{sub g}) density is about 0.1% of the total density. This plasma source has a flexible operation and potential for channeling the energy in ways that maximize the density of active species of interest.« less

Authors:
; ; ; ;  [1];  [2]
  1. Institute of Plasmas and Nuclear Fusion, Instituto Superior Tecnico, Technical University of Lisbon, 1049-001 Lisbon (Portugal)
  2. Lebedev Physical Institute of the Russian Academy of Sciences, 119991 Moscow (Russian Federation)
Publication Date:
OSTI Identifier:
22089556
Resource Type:
Journal Article
Journal Name:
Journal of Applied Physics
Additional Journal Information:
Journal Volume: 112; Journal Issue: 9; Other Information: (c) 2012 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0021-8979
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; AFTERGLOW; AIR; ATMOSPHERIC PRESSURE; FOURIER TRANSFORM SPECTROMETERS; GROUND STATES; HIGH-FREQUENCY DISCHARGES; HYDROXYL RADICALS; IONIZATION; MICROWAVE RADIATION; MIXTURES; NITROGEN DIOXIDE; NITROUS ACID; PLASMA; PLASMA DENSITY; PLASMA DIAGNOSTICS; PLASMA JETS; SIMULATION; WATER

Citation Formats

Tatarova, E., Henriques, J. P., Felizardo, E., Lino da Silva, M., Ferreira, C. M., and Gordiets, B. Microwave plasma source operating with atmospheric pressure air-water mixtures. United States: N. p., 2012. Web. doi:10.1063/1.4762015.
Tatarova, E., Henriques, J. P., Felizardo, E., Lino da Silva, M., Ferreira, C. M., & Gordiets, B. Microwave plasma source operating with atmospheric pressure air-water mixtures. United States. doi:10.1063/1.4762015.
Tatarova, E., Henriques, J. P., Felizardo, E., Lino da Silva, M., Ferreira, C. M., and Gordiets, B. Thu . "Microwave plasma source operating with atmospheric pressure air-water mixtures". United States. doi:10.1063/1.4762015.
@article{osti_22089556,
title = {Microwave plasma source operating with atmospheric pressure air-water mixtures},
author = {Tatarova, E. and Henriques, J. P. and Felizardo, E. and Lino da Silva, M. and Ferreira, C. M. and Gordiets, B.},
abstractNote = {The overall performance of a surface wave driven air-water plasma source operating at atmospheric pressure and 2.45 GHz has been analyzed. A 1D model previously developed has been improved in order to describe in detail the creation and loss processes of active species of interest. This model provides a complete characterization of the axial structure of the source, including the discharge and the afterglow zones. The main electron creation channel was found to be the associative ionization process N + O {yields} NO{sup +}+ e. The NO(X) relative density in the afterglow plasma jet ranges from 1.2% to 1.6% depending on power and water percentage, according to the model predictions and the measurements. Other types of species such as NO{sub 2} and nitrous acid HNO{sub 2} have also been detected by mass and Fourier Transform Infrared spectroscopy. The relative population density of O({sup 3}P) ground state atoms increases from 8% to 10% in the discharge zone when the input microwave power increases from 200 to 400 W and the water percentage from 1% to 10%. Furthermore, high densities of O{sub 2}(a{sup 1}{Delta}{sub g}) singlet delta oxygen molecules and OH radicals (1% and 5%, respectively) can be achieved in the discharge zone. In the late afterglow the O{sub 2}(a{sup 1}{Delta}{sub g}) density is about 0.1% of the total density. This plasma source has a flexible operation and potential for channeling the energy in ways that maximize the density of active species of interest.},
doi = {10.1063/1.4762015},
journal = {Journal of Applied Physics},
issn = {0021-8979},
number = 9,
volume = 112,
place = {United States},
year = {2012},
month = {11}
}