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Title: On the physical processes ruling an atmospheric pressure air glow discharge operating in an intermediate current regime

Abstract

Low-frequency (100 Hz), intermediate-current (50 to 200 mA) glow discharges were experimentally investigated in atmospheric pressure air between blunt copper electrodes. Voltage–current characteristics and images of the discharge for different inter-electrode distances are reported. A cathode-fall voltage close to 360 V and a current density at the cathode surface of about 11 A/cm{sup 2}, both independent of the discharge current, were found. The visible emissive structure of the discharge resembles to that of a typical low-pressure glow, thus suggesting a glow-like electric field distribution in the discharge. A kinetic model for the discharge ionization processes is also presented with the aim of identifying the main physical processes ruling the discharge behavior. The numerical results indicate the presence of a non-equilibrium plasma with rather high gas temperature (above 4000 K) leading to the production of components such as NO, O, and N which are usually absent in low-current glows. Hence, the ionization by electron-impact is replaced by associative ionization, which is independent of the reduced electric field. This leads to a negative current-voltage characteristic curve, in spite of the glow-like features of the discharge. On the other hand, several estimations show that the discharge seems to be stabilized by heat conduction; being thermally stable due tomore » its reduced size. All the quoted results indicate that although this discharge regime might be considered to be close to an arc, it is still a glow discharge as demonstrated by its overall properties, supported also by the presence of thermal non-equilibrium.« less

Authors:
; ; ;  [1];  [1];  [2]
  1. Grupo de Descargas Eléctricas, Departamento Ing. Electromecánica, Facultad Regional Venado Tuerto (UTN), Laprida 651, Venado Tuerto (2600), Santa Fe (Argentina)
  2. (CONICET), Facultad de Ciencias Exactas y Naturales (UBA) Ciudad Universitaria Pab. I, 1428, Buenos Aires (Argentina)
Publication Date:
OSTI Identifier:
22408144
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 22; Journal Issue: 2; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; AIR; ATMOSPHERIC PRESSURE; CATHODES; COPPER; CURRENT DENSITY; DISTANCE; ELECTRIC FIELDS; ELECTRIC POTENTIAL; ELECTRONS; GLOW DISCHARGES; IMAGES; IONIZATION; NITRIC OXIDE; NITROGEN; NON-EQUILIBRIUM PLASMA; OXYGEN; PRESSURE RANGE KILO PA; THERMAL CONDUCTION

Citation Formats

Prevosto, L., E-mail: prevosto@waycom.com.ar, Mancinelli, B., Chamorro, J. C., Cejas, E., Kelly, H., and Instituto de Física del Plasma. On the physical processes ruling an atmospheric pressure air glow discharge operating in an intermediate current regime. United States: N. p., 2015. Web. doi:10.1063/1.4907661.
Prevosto, L., E-mail: prevosto@waycom.com.ar, Mancinelli, B., Chamorro, J. C., Cejas, E., Kelly, H., & Instituto de Física del Plasma. On the physical processes ruling an atmospheric pressure air glow discharge operating in an intermediate current regime. United States. doi:10.1063/1.4907661.
Prevosto, L., E-mail: prevosto@waycom.com.ar, Mancinelli, B., Chamorro, J. C., Cejas, E., Kelly, H., and Instituto de Física del Plasma. 2015. "On the physical processes ruling an atmospheric pressure air glow discharge operating in an intermediate current regime". United States. doi:10.1063/1.4907661.
@article{osti_22408144,
title = {On the physical processes ruling an atmospheric pressure air glow discharge operating in an intermediate current regime},
author = {Prevosto, L., E-mail: prevosto@waycom.com.ar and Mancinelli, B. and Chamorro, J. C. and Cejas, E. and Kelly, H. and Instituto de Física del Plasma},
abstractNote = {Low-frequency (100 Hz), intermediate-current (50 to 200 mA) glow discharges were experimentally investigated in atmospheric pressure air between blunt copper electrodes. Voltage–current characteristics and images of the discharge for different inter-electrode distances are reported. A cathode-fall voltage close to 360 V and a current density at the cathode surface of about 11 A/cm{sup 2}, both independent of the discharge current, were found. The visible emissive structure of the discharge resembles to that of a typical low-pressure glow, thus suggesting a glow-like electric field distribution in the discharge. A kinetic model for the discharge ionization processes is also presented with the aim of identifying the main physical processes ruling the discharge behavior. The numerical results indicate the presence of a non-equilibrium plasma with rather high gas temperature (above 4000 K) leading to the production of components such as NO, O, and N which are usually absent in low-current glows. Hence, the ionization by electron-impact is replaced by associative ionization, which is independent of the reduced electric field. This leads to a negative current-voltage characteristic curve, in spite of the glow-like features of the discharge. On the other hand, several estimations show that the discharge seems to be stabilized by heat conduction; being thermally stable due to its reduced size. All the quoted results indicate that although this discharge regime might be considered to be close to an arc, it is still a glow discharge as demonstrated by its overall properties, supported also by the presence of thermal non-equilibrium.},
doi = {10.1063/1.4907661},
journal = {Physics of Plasmas},
number = 2,
volume = 22,
place = {United States},
year = 2015,
month = 2
}
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