Effects of compressibility on the magnetoRayleighTaylor instability in Zpinch implosions with sheared axial flows
Abstract
A linear analysis of the ideal magnetohydrodynamic (MHD) stability of the compressible Zpinch plasma with axial flow is presented. Comparing with results of incompressible models, compressibility can reduce the growth rate of the magnetoRayleighTaylor (MRT)/KelvinHelmholtz (KH) instability and allow sheared axial flows to mitigate the MRT instability far more effectively. The effect of magnetic field, which cannot be detected in an incompressible model, is also investigated. The result indicates that the mitigation effect of magnetic field on the MRT instability becomes significant as the perturbation wavenumber increases. Therefore, with the cooperation of sheared axial flow, magnetic field, and plasma compressibility, the stability of the Zpinch plasma is improved remarkably. In addition, the analysis also suggests that in an early stage of the implosion, because the plasma temperature is relatively low, the compressible model is much more suitable than the incompressible one based on the framework of MHD theory.
 Authors:
 Institute of Applied Physics and Computational Mathematics, P.O. Box 8009, Beijing 100088 (China)
 (China) and CCAST (World Laboratory), P.O. Box 8730, Beijing 100080 (China)
 Publication Date:
 OSTI Identifier:
 20782510
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physics of Plasmas; Journal Volume: 13; Journal Issue: 2; Other Information: DOI: 10.1063/1.2167912; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; COMPRESSIBILITY; COOPERATION; ELECTRON TEMPERATURE; HELMHOLTZ INSTABILITY; IMPLOSIONS; ION TEMPERATURE; LINEAR Z PINCH DEVICES; LONGITUDINAL PINCH; MAGNETIC FIELDS; MAGNETOHYDRODYNAMICS; PLASMA; RAYLEIGHTAYLOR INSTABILITY; SHEAR; STABILITY
Citation Formats
Zhang Yang, Ding Ning, and Institute of Applied Physics and Computational Mathematics, P.O. Box 8009, Beijing 100088. Effects of compressibility on the magnetoRayleighTaylor instability in Zpinch implosions with sheared axial flows. United States: N. p., 2006.
Web. doi:10.1063/1.2167912.
Zhang Yang, Ding Ning, & Institute of Applied Physics and Computational Mathematics, P.O. Box 8009, Beijing 100088. Effects of compressibility on the magnetoRayleighTaylor instability in Zpinch implosions with sheared axial flows. United States. doi:10.1063/1.2167912.
Zhang Yang, Ding Ning, and Institute of Applied Physics and Computational Mathematics, P.O. Box 8009, Beijing 100088. Wed .
"Effects of compressibility on the magnetoRayleighTaylor instability in Zpinch implosions with sheared axial flows". United States.
doi:10.1063/1.2167912.
@article{osti_20782510,
title = {Effects of compressibility on the magnetoRayleighTaylor instability in Zpinch implosions with sheared axial flows},
author = {Zhang Yang and Ding Ning and Institute of Applied Physics and Computational Mathematics, P.O. Box 8009, Beijing 100088},
abstractNote = {A linear analysis of the ideal magnetohydrodynamic (MHD) stability of the compressible Zpinch plasma with axial flow is presented. Comparing with results of incompressible models, compressibility can reduce the growth rate of the magnetoRayleighTaylor (MRT)/KelvinHelmholtz (KH) instability and allow sheared axial flows to mitigate the MRT instability far more effectively. The effect of magnetic field, which cannot be detected in an incompressible model, is also investigated. The result indicates that the mitigation effect of magnetic field on the MRT instability becomes significant as the perturbation wavenumber increases. Therefore, with the cooperation of sheared axial flow, magnetic field, and plasma compressibility, the stability of the Zpinch plasma is improved remarkably. In addition, the analysis also suggests that in an early stage of the implosion, because the plasma temperature is relatively low, the compressible model is much more suitable than the incompressible one based on the framework of MHD theory.},
doi = {10.1063/1.2167912},
journal = {Physics of Plasmas},
number = 2,
volume = 13,
place = {United States},
year = {Wed Feb 15 00:00:00 EST 2006},
month = {Wed Feb 15 00:00:00 EST 2006}
}

The stabilizing effect of different axial flow profiles on the magnetoRayleighTaylor (MTR) instability in Zpinch implosions is investigated with a compressible skincurrent model. The numerical results show that the mitigation effect of the axial flow on the MRT instability is caused by the radial velocity shear, and it is highly susceptible to the shear value nearby the plasma outer surface. By adjusting the flow profile, the mitigation effect can be improved markedly.

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