Abstract
The dynamics of convecting fluids in rotating spherical shells is governed at Prandtl numbers of the order unity by the interaction between differential rotation and roll-like convection eddies. While the differential rotation is driven by the Reynolds stresses of the eddies, its shearing action inhibits convection and causes phenomena such as localized convection and turbulent relaxation oscillations. The response of the system is enriched in the case of dynamo action. Lorentz forces may brake either entirely or partially the geostrophic differential rotation and give rise to two rather different dynamo states. Bistability of turbulent dynamos exists for magnetic Prandtl numbers of the order unity. While the ratios between mean magnetic and kinetic energies differ by a factor of 5 or more for the two dynamo states, the mean convective heat transports are nearly the same. They are much larger than in the absence of a magnetic field.
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References
Ardes, M., Busse, F.H., and Wicht, J.: Thermal convection in rotating spherical shells. Phys. Earth Planet. Inter., 99, 55–67 (1997)
Busse, F.H.: Convective flows in rapidly rotating spheres and their dynamo action, Phys. Fluids, 14, 1301–1314 (2002)
Busse, F.H., and Simitev, R.: Inertial convection in rotating fluid spheres. J. Fluid Mech., 498, 23–30 (2004)
Christensen, U.: Zonal flow driven by strongly supercritical convection in rotating spherical shells. J. Fluid Mech., 470, 115–133 (2002)
Dormy, E., and Soward, A.M., eds.: Mathematical Aspects of Natural Dynamos, CRC Press, Taylor & Francis Group, 2007
Grote, E., and Busse, F.H.: Dynamics of convection and dynamos in rotating spherical fluid shells. Fluid Dyn. Res., 28, 349–368 (2001)
Jones, C.A., Soward, A.M., and Mussa, A.I.: The onset of thermal convection in a rapidly rotating sphere. J. Fluid Mech., 405, 157–179 (2000)
Kutzner, C., and Christensen, U.: Driving mechanisms in geodynamo models. Geophys. Res. Lett., 27, 29–32 (2000)
Mujica, N., and Lathrop, D.P.: Bistability and hystreresis in a highly turbulent swirling flow, Physica A 49, 162–166 (2005)
Ravelet, F., Marié, L., Chiffaudel, A., and Daviaud, F.: Multistability and Memory Effect in a Highly Turbulent Flow: Experimental Evidence for a Global bifurcation, Phys. Rev. Lett. 93, 164501 (2004).
Simitev, R.D., and Busse, F.H.: Patterns of convection in rotating spherical shells, New J. Phys., 5, 97.1–97.20 (2003)
Simitev, R.D., and Busse, F. H.: Prandtl number dependence of convection-driven dynamos in rotating spherical fluid shells, J. Fluid Mech., 532, 365–388 (2003)
Simitev, R.D., and Busse, F.H.: Bistability and hysteresis of dipolar dynamos generated by turbulent convection in rotating spherical shells, Euro Phys. Lett., 85, 19001 (2009)
Tilgner, A., and Busse, F.H.: Finite amplitude convection in rotating spherical fluid shells, J. Fluid Mech., 332, 359–376 (1997)
Tilgner, A.: Spectral Methods for the Simulation of Incompressible Flows in Spherical Shells. Int. J. Numer. Meth. Fluids, 30, 713–724 (1999)
Zhang, K.-K., and Busse, F.H.: On the onset of convection in a rotating spherical shells. Geophys. Astrophys. Fluid Dyn., 39, 119–147 (1987)
Zhang, K.: On coupling between the Poincaré equation and the heat equation. J. Fluid Mech., 268, 211–229 (1994)
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Busse, F.H., Simitev, R.D. (2010). Some Unusual Properties of Turbulent Convection and Dynamos in Rotating Spherical Shells. In: Dritschel, D. (eds) IUTAM Symposium on Turbulence in the Atmosphere and Oceans. IUTAM Bookseries, vol 28. Springer, Dordrecht. https://doi.org/10.1007/978-94-007-0360-5_15
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DOI: https://doi.org/10.1007/978-94-007-0360-5_15
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