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Title: Convergence of shock waves between conical and parabolic boundaries

Abstract

Convergence of shock waves, generated by underwater electrical explosions of cylindrical wire arrays, between either parabolic or conical bounding walls is investigated. A high-current pulse with a peak of ∼550 kA and rise time of ∼300 ns was applied for the wire array explosion. Strong self-emission from an optical fiber placed at the origin of the implosion was used for estimating the time of flight of the shock wave. 2D hydrodynamic simulations coupled with the equations of state of water and copper showed that the pressure obtained in the vicinity of the implosion is ∼7 times higher in the case of parabolic walls. However, comparison with a spherical wire array explosion showed that the pressure in the implosion vicinity in that case is higher than the pressure in the current experiment with parabolic bounding walls because of strong shock wave reflections from the walls. It is shown that this drawback of the bounding walls can be significantly minimized by optimization of the wire array geometry.

Authors:
; ; ; ; ;  [1]
  1. Physics Department, Technion, Haifa 32000 (Israel)
Publication Date:
OSTI Identifier:
22600023
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 23; Journal Issue: 7; 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; COMPARATIVE EVALUATIONS; COMPUTERIZED SIMULATION; CONVERGENCE; COPPER; CYLINDRICAL CONFIGURATION; EQUATIONS OF STATE; EXPLOSIONS; GEOMETRY; HYDRODYNAMIC MODEL; IMPLOSIONS; OPTICAL FIBERS; OPTIMIZATION; PULSE RISE TIME; SHOCK WAVES; SPHERICAL CONFIGURATION; TIME-OF-FLIGHT METHOD; TWO-DIMENSIONAL CALCULATIONS; UNDERWATER; WALLS; WIRES

Citation Formats

Yanuka, D., Zinowits, H. E., Antonov, O., Efimov, S., Virozub, A., and Krasik, Ya. E. Convergence of shock waves between conical and parabolic boundaries. United States: N. p., 2016. Web. doi:10.1063/1.4959115.
Yanuka, D., Zinowits, H. E., Antonov, O., Efimov, S., Virozub, A., & Krasik, Ya. E. Convergence of shock waves between conical and parabolic boundaries. United States. doi:10.1063/1.4959115.
Yanuka, D., Zinowits, H. E., Antonov, O., Efimov, S., Virozub, A., and Krasik, Ya. E. 2016. "Convergence of shock waves between conical and parabolic boundaries". United States. doi:10.1063/1.4959115.
@article{osti_22600023,
title = {Convergence of shock waves between conical and parabolic boundaries},
author = {Yanuka, D. and Zinowits, H. E. and Antonov, O. and Efimov, S. and Virozub, A. and Krasik, Ya. E.},
abstractNote = {Convergence of shock waves, generated by underwater electrical explosions of cylindrical wire arrays, between either parabolic or conical bounding walls is investigated. A high-current pulse with a peak of ∼550 kA and rise time of ∼300 ns was applied for the wire array explosion. Strong self-emission from an optical fiber placed at the origin of the implosion was used for estimating the time of flight of the shock wave. 2D hydrodynamic simulations coupled with the equations of state of water and copper showed that the pressure obtained in the vicinity of the implosion is ∼7 times higher in the case of parabolic walls. However, comparison with a spherical wire array explosion showed that the pressure in the implosion vicinity in that case is higher than the pressure in the current experiment with parabolic bounding walls because of strong shock wave reflections from the walls. It is shown that this drawback of the bounding walls can be significantly minimized by optimization of the wire array geometry.},
doi = {10.1063/1.4959115},
journal = {Physics of Plasmas},
number = 7,
volume = 23,
place = {United States},
year = 2016,
month = 7
}
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