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Title: Numerical simulation of fiber and wire array Z-pinches with Trac-II

Abstract

Trac-II is a two dimensional axisymmetric resistive MHD code. It simulates all three spatial components (r, z, φ) of the magnetic field and fluid velocity vectors, and the plasma is treated as a single fluid with two temperatures (T e,T i). In addition, it can optionally include a self-consistent external circuit. Recent modifications to the code include the addition of the 3-T radiation model, a 4-phase (solid-liquid-vapor-plasma) equation of state model (QEOS), a 4-phase electrical/thermal conductivity model, and an implicit solution of poloidal B z,B r) magnetic field diffusion. These changes permit a detailed study of fiber and wire array Z-pinches. Specifically, Trac-II is used to study the wire array Z-pinch at the PBFA-Z pulse power generator at Sandia National Laboratory. First, in 1-D we examine the behavior of a single wire in the Z-pinch. Then, using these results as initial radial conditions in 2-D, we investigate the dynamics of wire array configurations in the r-z and r-θ plane. In the r-z plane we examine the growth of the m=0 or "sausage" instability in single wires within the array. In the r-θ plane we examine the merging behavior between neighboring wires. Special emphasis is placed on trying to explain howmore » instability growth affects the performance of the Z-pinch. Lastly, we introduce Trac-III, a 3-D MHD code, and illustrate the m=1 or "kink" instability. We also discuss how Trac-III can be modified to simulate the wire array Z-pinch.« less

Authors:
 [1]
+ Show Author Affiliations
  1. Univ. of California, Davis, CA (United States)
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE Office of Defense Programs (DP)
OSTI Identifier:
2451
Report Number(s):
UCRL-LR-131742
R&D Project: DP0102012; ON: DE00002451
DOE Contract Number:
W-7405-Eng-48
Resource Type:
Thesis/Dissertation
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION; Computerized Simulation; Pinch Devices; Wires

Citation Formats

Reisman, David B. Numerical simulation of fiber and wire array Z-pinches with Trac-II. United States: N. p., 1998. Web. doi:10.2172/2451.
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Reisman, David B. Numerical simulation of fiber and wire array Z-pinches with Trac-II. United States. doi:10.2172/2451.
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Reisman, David B. Tue . "Numerical simulation of fiber and wire array Z-pinches with Trac-II". United States. doi:10.2172/2451. https://www.osti.gov/servlets/purl/2451.
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@article{osti_2451,
title = {Numerical simulation of fiber and wire array Z-pinches with Trac-II},
author = {Reisman, David B.},
abstractNote = {Trac-II is a two dimensional axisymmetric resistive MHD code. It simulates all three spatial components (r, z, φ) of the magnetic field and fluid velocity vectors, and the plasma is treated as a single fluid with two temperatures (Te,Ti). In addition, it can optionally include a self-consistent external circuit. Recent modifications to the code include the addition of the 3-T radiation model, a 4-phase (solid-liquid-vapor-plasma) equation of state model (QEOS), a 4-phase electrical/thermal conductivity model, and an implicit solution of poloidal Bz,Br) magnetic field diffusion. These changes permit a detailed study of fiber and wire array Z-pinches. Specifically, Trac-II is used to study the wire array Z-pinch at the PBFA-Z pulse power generator at Sandia National Laboratory. First, in 1-D we examine the behavior of a single wire in the Z-pinch. Then, using these results as initial radial conditions in 2-D, we investigate the dynamics of wire array configurations in the r-z and r-θ plane. In the r-z plane we examine the growth of the m=0 or "sausage" instability in single wires within the array. In the r-θ plane we examine the merging behavior between neighboring wires. Special emphasis is placed on trying to explain how instability growth affects the performance of the Z-pinch. Lastly, we introduce Trac-III, a 3-D MHD code, and illustrate the m=1 or "kink" instability. We also discuss how Trac-III can be modified to simulate the wire array Z-pinch.},
doi = {10.2172/2451},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Sep 01 00:00:00 EDT 1998},
month = {Tue Sep 01 00:00:00 EDT 1998}
}
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Thesis/Dissertation:
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DOI:  10.2172/2451
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