Hostname: page-component-586b7cd67f-l7hp2 Total loading time: 0 Render date: 2024-11-26T00:36:34.479Z Has data issue: false hasContentIssue false

Asymptotic self-similar solutions for thermally isolated Z-pinches

Published online by Cambridge University Press:  10 May 2005

Y. M. SHTEMLER
Affiliation:
Pearlstone Center for Aeronautical Engineering Studies, Department of Mechanical Engineering, Ben-Gurion University of the Negev, P.O.B. 653, Beer-Sheva 84105, Israel ([email protected])
M. MOND
Affiliation:
Pearlstone Center for Aeronautical Engineering Studies, Department of Mechanical Engineering, Ben-Gurion University of the Negev, P.O.B. 653, Beer-Sheva 84105, Israel ([email protected])

Abstract

The dynamics of thermally-isolated Z-pinches carrying power law in time total currents (${\sim} t^S$) in magnetized resistive plasmas is studied. Time–space separable self-similar solutions with cylindrical symmetry are considered. The non-dimensional variables are chosen in a way that makes the problem consistent with the moderately resistive magnetohydrodynamic (MHD) model. For $S\,{=}\,{-}\frac15$ and Lundquist number $Lu\,{>}\, 1.5$ a non-equilibrium solution is obtained in addition to the conventional solutions for either exact, $S\,{=}\,{\pm}\frac13$, or asymptotic, $Lu\,{=}\,\infty$, equilibria (the latter is homogeneously valid for long times only if $S\,{>}\,{-}\frac15$). The problem is treated asymptotically for high dimensionless thermal-conductivity, which is proportional to the square root of the ion/electron mass ratio. To obtain a closure condition for the leading-order isothermal solution, the first-order terms in the energy equation are invoked. Radial profiles are found explicitly which depend on $S$ for equilibrium, and on $Lu$ for non-equilibrium solutions. The multiplicity of the self-similar solutions is investigated.

Type
Papers
Copyright
2005 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)