Abstract
The flow generated by a random buoyancy field in a rotating medium permeated by a dynamo-generated magnetic field is considered, under the assumptions that the Rossby number and the magnetic Reynolds number (based on the scale of the buoyancy fluctuations) are both small. This permits linearisation of the governing evolution equations. Provided ‘up-down’ symmetry is broken, a mean helicity and an associated α-effect are generated. These are calculated in terms of the spectrum function of the buoyancy field. Expressions are also obtained for the buoyancy flux and the Reynolds stresses (kinetic and magnetic), and an outline dynamo scenario is proposed. The nature of this type of magnetostrophic turbulence is briefly discussed.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
References 51
Moffatt HK (1989) In: Lielpeteris J, Moreau R (eds) Liquid metal magnetohy-drodynamics. Kluwer:403-412
Moffatt HK, Loper D (1994) Geophys J Int 117:394-402
St Pierre MG (1996) Geophys Astrophys Fluid Dyn 83:293-296
Siso-Nadal F, Davidson PA (2004) Phys Fluids 16:1242-1254
Braginski SI (1967) Geomag Aeron 4:572-583
Drobyshevsky EM, Yuferev VS (1974) J Fluid Mech 65:41-43
Moffatt HK (1978) Magnetic Field Generation in Electrically Conducting Fluids. Cambridge University Press (see also <www.moffatt.tc>)
Moffatt HK (1972) J Fluid Mech 53:385-399
Batchelor GK (1959) J Fluid Mech 5:113-133
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2008 Springer
About this paper
Cite this paper
Moffatt, H.K. (2008). Magnetostrophic Turbulence and the Geodynamo. In: Kaneda, Y. (eds) IUTAM Symposium on Computational Physics and New Perspectives in Turbulence. IUTAM Bookseries, vol 4. Springer, Dordrecht. https://doi.org/10.1007/978-1-4020-6472-2_51
Download citation
DOI: https://doi.org/10.1007/978-1-4020-6472-2_51
Publisher Name: Springer, Dordrecht
Print ISBN: 978-1-4020-6471-5
Online ISBN: 978-1-4020-6472-2
eBook Packages: EngineeringEngineering (R0)