Exact scaling laws and the local structure of isotropic magnetohydrodynamic turbulence
- 7 March 2007
- journal article
- research article
- Published by Cambridge University Press (CUP) in Journal of Fluid Mechanics
- Vol. 575, 111-120
Abstract
This paper examines the consistency of the exact scaling laws for isotropic magnetohydrodynamic (MHD) turbulence in numerical simulations with large magnetic Prandtl numbersPmand withPm= 1. The exact laws are used to elucidate the structure of the magnetic and velocity fields. Despite the linear scaling of certain third-order correlation functions, the situation is not analogous to the case of Kolmogorov turbulence. The magnetic field is adequately described by a model of a stripy (folded) field with direction reversals at the resistive scale. At currently available resolutions, the cascade of kinetic energy is short-circuited by the direct exchange of energy between the forcing-scale motions and the stripy magnetic fields. This non-local interaction is the defining feature of isotropic MHD turbulence.Keywords
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This publication has 16 references indexed in Scilit:
- Small-scale statistics of viscoelastic turbulenceEurophysics Letters, 2006
- Anisotropy, inhomogeneity and inertial-range scalings in turbulent convectionJournal of Fluid Mechanics, 2006
- Shell-to-shell energy transfer in magnetohydrodynamics. I. Steady state turbulencePhysical Review E, 2005
- Simulations of the Small‐Scale Turbulent DynamoThe Astrophysical Journal, 2004
- A model of nonlinear evolution and saturation of the turbulent MHD dynamoNew Journal of Physics, 2002
- Dynamical length scales for turbulent magnetized flowsGeophysical Research Letters, 1998
- von Kármán–Howarth equation for magnetohydrodynamics and its consequences on third-order longitudinal structure and correlation functionsPhysical Review E, 1998
- Magnetic eddies in an incompressible viscous fluid of high electrical conductivityJournal of Fluid Mechanics, 1963
- The invariant theory of isotropic turbulence in magneto-hydrodynamicsProceedings of the Royal Society of London. A. Mathematical and Physical Sciences, 1951
- On the spontaneous magnetic field in a conducting liquid in turbulent motionProceedings of the Royal Society of London. A. Mathematical and Physical Sciences, 1950