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Title: Experimental investigation on the effect of plasma jet in the triggered discharge process of a gas switch

Abstract

The temporal and spatial evolution of a plasma jet generated by a spark discharge was observed. The electron temperature and density were obtained under different time and gas pressures by optical emission spectroscopy. Moreover, the discharge process of the plasma-jet triggered gas switch was recorded and analyzed at the lowest working coefficient. The results showed that the plasma jet moved forward in a bullet mode, and the advancing velocity increased with the decrease of pressure, and decreased with time growing. At initial time, the maximum velocity of a plasma jet could reach 3.68 × 10{sup 6 }cm/s. The electron temperature decreased from 2.0 eV to 1.3 eV, and the electron density increased from 3.1 × 10{sup 15}/cm{sup 3} to 6.3 × 10{sup 15}/cm{sup 3} at the initial moment as the gas pressure increases from 0.1 MPa to 0.32 MPa. For a two-gap gas switch, the discharge performances were more depended on the second discharge spark gap (gap 2). Because plasma jet promoted the discharge in Gap 2, the gas switch operating in mode II had better triggered discharge characteristics. In the discharge process, the plasma-jet triggering had the effect of non-penetrating inducing, which not only provided initial electrons for reducing statistical lag but also enhanced the local electric field. The dischargemore » was initiated and accelerated from electron avalanche to streamer. Therefore, a fast discharge was occurred in the gas switch.« less

Authors:
 [1];  [2]; ; ;  [3]
  1. Xi'an Electronic Engineering Research Institute, Xi'an 710100 (China)
  2. (China)
  3. Xi'an Jiaotong University, Xi'an 710049 (China)
Publication Date:
OSTI Identifier:
22599949
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 23; Journal Issue: 8; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ELECTRIC FIELDS; ELECTRON DENSITY; ELECTRON TEMPERATURE; ELECTRONS; EMISSION SPECTROSCOPY; PLASMA JETS; PRESSURE RANGE MEGA PA 01-10; SPARK GAPS; SWITCHES; VELOCITY

Citation Formats

Tie, W., E-mail: twh.110.666@163.com, E-mail: 84470220@qq.com, Xi'an Jiaotong University, Xi'an 710049, Liu, S., Liu, X., and Zhang, Q. Experimental investigation on the effect of plasma jet in the triggered discharge process of a gas switch. United States: N. p., 2016. Web. doi:10.1063/1.4960322.
Tie, W., E-mail: twh.110.666@163.com, E-mail: 84470220@qq.com, Xi'an Jiaotong University, Xi'an 710049, Liu, S., Liu, X., & Zhang, Q. Experimental investigation on the effect of plasma jet in the triggered discharge process of a gas switch. United States. doi:10.1063/1.4960322.
Tie, W., E-mail: twh.110.666@163.com, E-mail: 84470220@qq.com, Xi'an Jiaotong University, Xi'an 710049, Liu, S., Liu, X., and Zhang, Q. 2016. "Experimental investigation on the effect of plasma jet in the triggered discharge process of a gas switch". United States. doi:10.1063/1.4960322.
@article{osti_22599949,
title = {Experimental investigation on the effect of plasma jet in the triggered discharge process of a gas switch},
author = {Tie, W., E-mail: twh.110.666@163.com, E-mail: 84470220@qq.com and Xi'an Jiaotong University, Xi'an 710049 and Liu, S. and Liu, X. and Zhang, Q.},
abstractNote = {The temporal and spatial evolution of a plasma jet generated by a spark discharge was observed. The electron temperature and density were obtained under different time and gas pressures by optical emission spectroscopy. Moreover, the discharge process of the plasma-jet triggered gas switch was recorded and analyzed at the lowest working coefficient. The results showed that the plasma jet moved forward in a bullet mode, and the advancing velocity increased with the decrease of pressure, and decreased with time growing. At initial time, the maximum velocity of a plasma jet could reach 3.68 × 10{sup 6 }cm/s. The electron temperature decreased from 2.0 eV to 1.3 eV, and the electron density increased from 3.1 × 10{sup 15}/cm{sup 3} to 6.3 × 10{sup 15}/cm{sup 3} at the initial moment as the gas pressure increases from 0.1 MPa to 0.32 MPa. For a two-gap gas switch, the discharge performances were more depended on the second discharge spark gap (gap 2). Because plasma jet promoted the discharge in Gap 2, the gas switch operating in mode II had better triggered discharge characteristics. In the discharge process, the plasma-jet triggering had the effect of non-penetrating inducing, which not only provided initial electrons for reducing statistical lag but also enhanced the local electric field. The discharge was initiated and accelerated from electron avalanche to streamer. Therefore, a fast discharge was occurred in the gas switch.},
doi = {10.1063/1.4960322},
journal = {Physics of Plasmas},
number = 8,
volume = 23,
place = {United States},
year = 2016,
month = 8
}
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