Sign on

SAO/NASA ADS Astronomy Abstract Service


· Find Similar Abstracts (with default settings below)
· Full Refereed Journal Article (PDF/Postscript)
· Full Refereed Scanned Article (GIF)
· References in the article
· Citations to the Article (21) (Citation History)
· Refereed Citations to the Article
· Also-Read Articles (Reads History)
·
· Translate This Page
Title:
A Numerical Study of Rayleigh-Taylor Instability in Magnetic Fluids
Authors:
Jun, Byung-Il; Norman, Michael L.; Stone, James M.
Publication:
Astrophysical Journal v.453, p.332 (ApJ Homepage)
Publication Date:
11/1995
Origin:
APJ; KNUDSEN
Astronomy Keywords:
INSTABILITIES, MAGNETIC FIELDS, METHODS: NUMERICAL, MAGNETOHYDRODYNAMICS: MHD, TURBULENCE
DOI:
10.1086/176393
Bibliographic Code:
1995ApJ...453..332J

Abstract

Mixing by the Rayleigh-Taylor (R-T) instability in incompressible magnetic fluids is studied with two- and three-dimensional ideal MHD simulations. Evolution and amplification of magnetic fields in the Rayleigh- Taylor instability are explored in the linear and nonlinear regime for various perturbations. In a single-mode perturbation, both tangential and normal magnetic fields to the density interface decrease the growth of instabilities, while a tangential field is more efficient in stabilizing the flow, as predicted by linear theory. However, the growth of a multiple-mode perturbation in the nonlinear regime tends to be enhanced by a normal magnetic field because the flow is collimated along the field lines. A strong tangential field suppresses the growth of short-wavelength modes, as expected from linear theory. Three-dimensional numerical simulations are carried out to study the amplification of magnetic fields in the turbulent mixing layer developed by the instability in the nonlinear regime. We find the following results. (1) The turbulent flow amplifies the magnetic field more efficiently in three-dimensions than in two-dimensions. (2) The peak of the magnetic energy spectrum occurs at high wavenumbers, which means that the field is amplified preferentially on small scales. (3) The peak of the kinetic energy spectrum is at scales significantly longer than the grid scale, is independent of grid resolution, and reflects the characteristic size of the R-T fingers at a given time. (4) Secondary Kelvin-Helmholtz instabilities generate vortex rings and ring-structured magnetic fields. However, the stretching of field lines by R-T fingers is the dominant amplification mechanism. (5) The final structures are very sensitive to the initial magnetic field and numerical resolution. (6) The magnetic field component along the gravity vector dominates as the instabilities grow. This dominance is stronger in three dimensions than in two dimensions, but it becomes less dominant as the resolution increases. (7) Higher resolution produces a greater total magnetic energy and a smaller total kinetic energy.

Printing Options

Print whole paper
Print Page(s) through

Return 600 dpi PDF to Acrobat/Browser. Different resolutions (200 or 600 dpi), formats (Postscript, PDF, etc), page sizes (US Letter, European A4, etc), and compression (gzip,compress,none) can be set through the Printing Preferences



More Article Retrieval Options

HELP for Article Retrieval


Bibtex entry for this abstract   Preferred format for this abstract (see Preferences)

  New!

Find Similar Abstracts:

Use: Authors
Title
Keywords (in text query field)
Abstract Text
Return: Query Results Return    items starting with number
Query Form
Database: Astronomy
Physics
arXiv e-prints