Baroclinically-driven flows and dynamo action in rotating spherical fluid shells

Simitev, R. D. and Busse, F. H. (2017) Baroclinically-driven flows and dynamo action in rotating spherical fluid shells. Geophysical and Astrophysical Fluid Dynamics, 111(5), pp. 369-379. (doi:10.1080/03091929.2017.1361945)

[img]
Preview
Text
144981.pdf - Accepted Version

1MB

Abstract

The dynamics of stably stratified stellar radiative zones is of considerable interest due to the availability of increasingly detailed observations of Solar and stellar interiors. This article reports the first non-axisymmetric and time-dependent simulations of flows of anelastic fluids driven by baroclinic torques in stably stratified rotating spherical shells – a system serving as an elemental model of a stellar radiative zone. With increasing baroclinicity a sequence of bifurcations from simpler to more complex flows is found in which some of the available symmetries of the problem are broken subsequently. The poloidal component of the flow grows relative to the dominant toroidal component with increasing baroclinicity. The possibility of magnetic field generation thus arises and this paper proceeds to provide some indications for self-sustained dynamo action in baroclinically-driven flows. We speculate that magnetic fields in stably stratified stellar interiors are thus not necessarily of fossil origin as it is often assumed.

Item Type:Articles
Additional Information:This work was supported by NASA [grant number NNX-09AJ85G] and the Leverhulme Trust [grant number RPG-2012-600].
Status:Published
Refereed:Yes
Glasgow Author(s) Enlighten ID:Simitev, Dr Radostin
Authors: Simitev, R. D., and Busse, F. H.
College/School:College of Science and Engineering > School of Mathematics and Statistics
Journal Name:Geophysical and Astrophysical Fluid Dynamics
Publisher:Taylor & Francis
ISSN:0309-1929
ISSN (Online):1029-0419
Published Online:10 August 2017

University Staff: Request a correction | Enlighten Editors: Update this record

Project CodeAward NoProject NamePrincipal InvestigatorFunder's NameFunder RefLead Dept
570591Two-layer thermo-compositional dynamo models of the geomagnetic field.Radostin SimitevLeverhulme Trust (LEVERHUL)RPG-2012-600M&S - MATHEMATICS