Instability of non-linear α2-dynamos

Details Instability of non-linear α2-dynamos Instability of non-linear α2-dynamos

May 2004

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2004pepi..142..101f&link_type=abstract

Physics of the Earth and Planetary Interiors, Volume 142, Issue 1-2, p. 101-112.

Physics

1

Scientific paper

Studies of the stability of prescribed magnetic fields in rapidly rotating systems have clearly demonstrated the relevance of the mechanism of magnetic field instability to the dynamics of planetary cores, see for example [Magnetic instabilities in rapidly rotating systems. In: Proctor, M.R.E., Matthews, P.C., Rucklidge, A.M. (Eds.), Solar and Planetary Dynamos. CUP, 1993, p. 59] The present study investigates the non-linear development of such instabilities and their feedback on the field generation process. The non-axisymmetric instability of a mean magnetic field B generated by a prescribed α-effect has been investigated in a rapidly rotating fluid spherical shell. The mean field drives a flow through the Lorentz force in the momentum equation and this flow feeds back on the field-generation process in the magnetic induction equation, equilibrating the field at some finite amplitude. This amplitude increases with α0, the strength of α. Above some critical value of α0, the mean field becomes unstable to a non-axisymmetric instability. The present work is the continuation of preliminary work by [Phys. Earth Planet. Inter. 134 (2002) 213] to higher values of α0, and to a different, more realistic, form of α. We are particularly interested in how the instability affects the mean field generated. We find that instability can dramatically reduce the strength of the mean field and significantly constrains the growth of B with α0.
On leave from: Department of Mathematics, University of Dhaka, Dhaka 1000, Bangladesh.

Affiliated with

Also associated with

No associations

Rating

Instability of non-linear α2-dynamos does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Instability of non-linear α2-dynamos, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Instability of non-linear α2-dynamos will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1552522