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Title: Voltage and pressure scaling of streamer dynamics in a helium plasma jet with N{sub 2} co-flow

Abstract

Positive polarity applied voltage and gas pressure dependent scaling of cathode directed streamer propagation properties in helium gas flow guided capillary dielectric barrier discharge have been quantified from streamer velocity, streamer current, and streamer optical diameter measurements. All measurements of the non-stochastic streamer properties have been performed in a variable gas pressure glass cell with N{sub 2} co-flow and under self-consistent Poisson electric field dominated conditions to permit data comparison with 2-D streamer dynamics models in air/nitrogen. The streamer optical diameter was found to be nearly independent of both gas pressures, from 170 Torr up to 760 Torr, and also for applied voltages from 6 to 11 kV at 520 Torr. The streamer velocity was found to increase quadratically with increased applied voltage. These observed differences in the 2-D scaling properties of ionization wave sustained cathode directed streamer propagation in helium flow channel with N{sub 2} annular co-flow compared to the streamer propagation in air or nitrogen have been shown to be caused by the remnant ionization distribution due to large differences in the dissociative recombination rates of He{sub 2}{sup +} versus N{sub 4}{sup +} ions, for this 5 kHz repetition rate applied voltage pulse generated streamers.

Authors:
 [1]; ;  [2]
  1. UES, Inc., 4401 Dayton-Xenia Road, Dayton, Ohio 45432 (United States)
  2. Air Force Research Laboratory, Wright-Patterson Air Force Base, Ohio 45433-7919 (United States)
Publication Date:
OSTI Identifier:
22303808
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 21; Journal Issue: 8; Other Information: (c) 2014 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; COMPARATIVE EVALUATIONS; ELECTRIC POTENTIAL; GAS FLOW; HELIUM; IONIZATION; IONS; KHZ RANGE 01-100; NITROGEN; PLASMA JETS; PRESSURE DEPENDENCE

Citation Formats

Leiweke, Robert J., Ganguly, Biswa N., and Scofield, James D.. Voltage and pressure scaling of streamer dynamics in a helium plasma jet with N{sub 2} co-flow. United States: N. p., 2014. Web. doi:10.1063/1.4892968.
Leiweke, Robert J., Ganguly, Biswa N., & Scofield, James D.. Voltage and pressure scaling of streamer dynamics in a helium plasma jet with N{sub 2} co-flow. United States. doi:10.1063/1.4892968.
Leiweke, Robert J., Ganguly, Biswa N., and Scofield, James D.. Fri . "Voltage and pressure scaling of streamer dynamics in a helium plasma jet with N{sub 2} co-flow". United States. doi:10.1063/1.4892968.
@article{osti_22303808,
title = {Voltage and pressure scaling of streamer dynamics in a helium plasma jet with N{sub 2} co-flow},
author = {Leiweke, Robert J. and Ganguly, Biswa N. and Scofield, James D.},
abstractNote = {Positive polarity applied voltage and gas pressure dependent scaling of cathode directed streamer propagation properties in helium gas flow guided capillary dielectric barrier discharge have been quantified from streamer velocity, streamer current, and streamer optical diameter measurements. All measurements of the non-stochastic streamer properties have been performed in a variable gas pressure glass cell with N{sub 2} co-flow and under self-consistent Poisson electric field dominated conditions to permit data comparison with 2-D streamer dynamics models in air/nitrogen. The streamer optical diameter was found to be nearly independent of both gas pressures, from 170 Torr up to 760 Torr, and also for applied voltages from 6 to 11 kV at 520 Torr. The streamer velocity was found to increase quadratically with increased applied voltage. These observed differences in the 2-D scaling properties of ionization wave sustained cathode directed streamer propagation in helium flow channel with N{sub 2} annular co-flow compared to the streamer propagation in air or nitrogen have been shown to be caused by the remnant ionization distribution due to large differences in the dissociative recombination rates of He{sub 2}{sup +} versus N{sub 4}{sup +} ions, for this 5 kHz repetition rate applied voltage pulse generated streamers.},
doi = {10.1063/1.4892968},
journal = {Physics of Plasmas},
number = 8,
volume = 21,
place = {United States},
year = {Fri Aug 15 00:00:00 EDT 2014},
month = {Fri Aug 15 00:00:00 EDT 2014}
}
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