J. Fluid Mech.
419 (2000) 283-323.
doi:10.1017/S0022112000001373
Compressible magnetoconvection in three dimensions:
pattern formation in a strongly stratified layer
A.M.Rucklidge(1),
N.O. Weiss(1),
D.P. Brownjohn(1),
P.C. Matthews(1,2) and
M.R.E. Proctor(1)
(1) Department of Applied Mathematics and Theoretical Physics,
University of Cambridge, Cambridge, CB3 9EW, UK
(2) School of Mathematical Sciences, University of Nottingham,
University Park, Nottingham, NG7 2RD, UK
Abstract.
The interaction between magnetic fields and convection is interesting both
because of its astrophysical importance and because the nonlinear Lorentz
force leads to an especially rich variety of behaviour. We present several
sets of computational results for magnetoconvection in a square box, with
periodic lateral boundary conditions, that show transitions from steady
convection with an ordered planform through a regime with intermittent
bursts to complicated spatiotemporal behaviour. The constraints imposed
by the square lattice are relaxed as the aspect ratio is increased.
In wide boxes we find a new regime, in which regions with strong fields
are separated from regions with vigorous convection. We show also how
considerations of symmetry and associated group theory can be used to
explain the nature of these transitions and the sequence in which the
relevant bifurcations occur.
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