Finite Larmor radius magnetohydrodynamic analysis of the Rayleigh-Taylor instability in Z pinches with sheared axial flow

Journal Article · Thu Mar 15 04:00:00 EDT 2007 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.2717583· OSTI ID:20974870

Qiu, X M; Huang, L; Jian, G D ^[1]

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1. Southwestern Institute of Physics, P. O. Box 432, Chengdu 610041 (China)

The Rayleigh-Taylor (RT) instability in Z pinches with sheared axial flow (SAF) is analyzed using finite Larmor radius (FLR) magnetohydrodynamic theory, in whose momentum equation the FLR effect (also referred to as the effect of gyroviscosity) is introduced through an anisotropic ion (FLR) stress tensor. A dispersion relation is derived for the linear RT instability. Both analytical and numerical solutions of the dispersion equation are given. The results indicate that the short-wavelength modes of the RT instability can be stabilized by a sufficient FLR, whereas the long-wavelength modes can be stabilized by a sufficient SAF. In the small-wavenumber region, for normalized wavenumber K<2.4, the hybrid RT/KH (Kelvin-Helmholtz) instability is shown to be the most difficult to stabilize. However the synergistic effect of the SAF and gyroviscosity can mitigate both the RT instability in the large-wavenumber region (K>2.4) and the hybrid RT/KH instability in the small-wavenumber region. In addition, this synergistic effect can compress the RT instability to a narrow wavenumber region. Even the thorough stabilization of the RT instability in the large-wavenumber region is possible with a sufficient SAF and a sufficient gyroviscosity.

• OSTI ID: 20974870
• Journal Information: Physics of Plasmas, Journal Name: Physics of Plasmas Journal Issue: 3 Vol. 14; ISSN PHPAEN; ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ANISOTROPY
DISPERSION RELATIONS
DISPERSIONS
EQUATIONS
HELMHOLTZ INSTABILITY
IONS
LARMOR RADIUS
MAGNETOHYDRODYNAMICS
NUMERICAL SOLUTION
PLASMA
RAYLEIGH-TAYLOR INSTABILITY
SHEAR
STABILIZATION
STRESSES
TENSORS
WAVELENGTHS