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Title: Radiation-MHD simulations for the development of a spark discharge channel.

Abstract

The growth of a cylindrical s park discharge channel in water and Lexan is studied using a series of one - dimensional simulations with the finite - element radiation - magnetohydrodynamics code ALEGRA. Computed solutions are analyzed in order to characterize the rate of growth and dynamics of the spark c hannels during the rising - current phase of the drive pulse. The current ramp rate is varied between 0.2 and 3.0 kA/ns, and values of the mechanical coupling coefficient K p are extracted for each case. The simulations predict spark channel expansion veloc ities primarily in the range of 2000 to 3500 m/s, channel pressures primarily in the range 10 - 40 GPa, and K p values primarily between 1.1 and 1.4. When Lexan is preheated, slightly larger expansion velocities and smaller K p values are predicted , but the o verall behavior is unchanged.

Authors:
 [1];  [1];  [1];  [1]
  1. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Publication Date:
Research Org.:
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Sponsoring Org.:
USDOE National Nuclear Security Administration (NNSA)
OSTI Identifier:
1365528
Report Number(s):
SAND2017-4461
652832
DOE Contract Number:
AC04-94AL85000
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS

Citation Formats

Niederhaus, John Henry, Jorgenson, Roy E., Warne, Larry K., and Chen, Kenneth C. Radiation-MHD simulations for the development of a spark discharge channel.. United States: N. p., 2017. Web. doi:10.2172/1365528.
Niederhaus, John Henry, Jorgenson, Roy E., Warne, Larry K., & Chen, Kenneth C. Radiation-MHD simulations for the development of a spark discharge channel.. United States. doi:10.2172/1365528.
Niederhaus, John Henry, Jorgenson, Roy E., Warne, Larry K., and Chen, Kenneth C. Sat . "Radiation-MHD simulations for the development of a spark discharge channel.". United States. doi:10.2172/1365528. https://www.osti.gov/servlets/purl/1365528.
@article{osti_1365528,
title = {Radiation-MHD simulations for the development of a spark discharge channel.},
author = {Niederhaus, John Henry and Jorgenson, Roy E. and Warne, Larry K. and Chen, Kenneth C.},
abstractNote = {The growth of a cylindrical s park discharge channel in water and Lexan is studied using a series of one - dimensional simulations with the finite - element radiation - magnetohydrodynamics code ALEGRA. Computed solutions are analyzed in order to characterize the rate of growth and dynamics of the spark c hannels during the rising - current phase of the drive pulse. The current ramp rate is varied between 0.2 and 3.0 kA/ns, and values of the mechanical coupling coefficient K p are extracted for each case. The simulations predict spark channel expansion veloc ities primarily in the range of 2000 to 3500 m/s, channel pressures primarily in the range 10 - 40 GPa, and K p values primarily between 1.1 and 1.4. When Lexan is preheated, slightly larger expansion velocities and smaller K p values are predicted , but the o verall behavior is unchanged.},
doi = {10.2172/1365528},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sat Apr 01 00:00:00 EDT 2017},
month = {Sat Apr 01 00:00:00 EDT 2017}
}

Technical Report:

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