Convection in a rotating magnetic system and Taylor's constraint
- 1 December 1988
- journal article
- research article
- Published by Taylor & Francis in Geophysical & Astrophysical Fluid Dynamics
- Vol. 44 (1) , 91-116
- https://doi.org/10.1080/03091928808208880
Abstract
A system is considered in which electrically conducting fluid is contained between two rigid horizontal planes and bounded laterally by a circular cylinder. The fluid is permeated by a strong azimuthal magnetic field. The strength of the field increases linearly with distance from the vertical axis of the cylinder, about which the entire system rotates rapidly. An unstable temperature gradient is maintained by heating the fluid from below and cooling from above. When viscosity and inertia are neglected, an arbitrary geostrophic velocity, which is aligned with the applied azimuthal magnetic field and independent of the axial coordinate, can be superimposed on the basic axisymmetric state. In this inviscid limit, the geostrophic velocity which occurs at the onset of convection is such that the net torque on geostrophic cylinders vanishes (Taylor's condition). The mathematical problem which describes the ensuing marginal convection is nonlinear, and was discussed previously for the planar case by Soward (1986). Here new features are isolated which result from the cylindrical geometry. New asymptotic solutions are derived valid when Taylor's condition is relaxed to include viscous effects.Keywords
This publication has 22 references indexed in Scilit:
- αω-Dynamos and Taylor's constraintGeophysical & Astrophysical Fluid Dynamics, 1988
- A model-Z geodynamoGeophysical & Astrophysical Fluid Dynamics, 1987
- Hydromagnetic waves in a differentially rotating Annulus I. A test of local stability analysisGeophysical & Astrophysical Fluid Dynamics, 1983
- Local analysis of thermal and magnetic instabilities in a rapidly rotating fluidGeophysical & Astrophysical Fluid Dynamics, 1983
- Boundary conditions for a rapidly rotating hydromagnetic system in a cylindrical containerGeophysical & Astrophysical Fluid Dynamics, 1983
- ‘Stable’ density stratification as a catalyst for instabilityJournal of Fluid Mechanics, 1980
- Thermally driven hydromagnetic convection in a rapidly rotating sphereProceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences, 1979
- Thermal and magnetic instabilities in a rapidly rotating fluid sphereGeophysical & Astrophysical Fluid Dynamics, 1979
- Hydromagnetic convective instability of a rotating, self-gravitating fluid sphere containing a uniform distribution of heat sourcesProceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences, 1977
- On the nearly axially-symmetrical model of the hydromagnetic dynamo of the earthPhysics of the Earth and Planetary Interiors, 1976