ON HYDROMAGNETIC CRITICAL LAYERS.

I. A. Eltayeb, M. H A Hassan

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

When a horizontal magnetic field B(z) is sheared vertically on a lengthscale L in a diffusionless fluid, critical layers occur at z//c where the local Alfven speed V(z//c) matches the phase speed c of the wave. However, when a vertical field B//z is introduced, all the critical layers disappear. The present study investigates the solution in the neighborhood of z//c when B//z/B is very small, in order to clarify the manner in which the vertical field annihilates the critical layers. It is found that the solution across the critical layer is adjusted in a thin magnetic layer whose thickness is determined by the parameter epsilon **2( equals U/ alpha V, where U, V are measures of the vertical and horizontal components of the Alfven velocity and alpha /L is the horizontal wavenumber). The influence of the vertical field on the resistive instabilities present in its absence is also examined.

Original languageEnglish
Pages (from-to)117-130
Number of pages14
JournalJournal of Fluid Mechanics
Volume167
Publication statusPublished - Jun 1986

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magnetohydrodynamics
Magnetic fields
Fluids
fluids
magnetic fields

ASJC Scopus subject areas

  • Computational Mechanics
  • Mechanics of Materials
  • Physics and Astronomy(all)
  • Condensed Matter Physics

Cite this

ON HYDROMAGNETIC CRITICAL LAYERS. / Eltayeb, I. A.; Hassan, M. H A.

In: Journal of Fluid Mechanics, Vol. 167, 06.1986, p. 117-130.

Research output: Contribution to journalArticle

Eltayeb, IA & Hassan, MHA 1986, 'ON HYDROMAGNETIC CRITICAL LAYERS.', Journal of Fluid Mechanics, vol. 167, pp. 117-130.
Eltayeb, I. A. ; Hassan, M. H A. / ON HYDROMAGNETIC CRITICAL LAYERS. In: Journal of Fluid Mechanics. 1986 ; Vol. 167. pp. 117-130.
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