A self-sustaining nonlinear dynamo process in Keplerian shear flows

Abstract

A three-dimensional nonlinear dynamo process is identified in rotating plane Couette flow in the Keplerian regime. It is analogous to the hydrodynamic self-sustaining process in non-rotating shear flows and relies on the magneto-rotational instability of a toroidal magnetic field. Steady nonlinear solutions are computed numerically for a wide range of magnetic Reynolds numbers but are restricted to low Reynolds numbers. This process may be important to explain the sustenance of coherent fields and turbulent motions in Keplerian accretion disks, where all its basic ingredients are present.

4 pages, 7 figures, accepted for publication in Physical Review Letters

References in corpus (3)

• The Effect of Resistivity on the Nonlinear Stage of the Magnetorotational Instability in Accretion Disks
• Direct magnetic field detection in the innermost regions of an accretion disc
• On self-sustaining processes in Rayleigh-stable rotating plane Couette flows and subcritical transition to turbulence in accretion disks

Cited by in corpus (42)

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• Helical magnetorotational instability in a Taylor-Couette flow with strongly reduced Ekman pumping
• On Self-Sustained Dynamo Cycles in Accretion Discs
• Magnetohydrodynamic experiments on cosmic magnetic fields
• Experimental evidence for non-axisymmetric magnetorotational instability in a rotating liquid metal exposed to an azimuthal magnetic field
• Saturation of the magnetorotational instability in the unstratified shearing box with zero net flux: convergence in taller boxes
• Global bifurcations to subcritical magnetorotational dynamo action in Keplerian shear flow
• High accretion rates in magnetised Keplerian discs mediated by a Parker instability driven dynamo
• Large-Scale Magnetic-Field Generation by Randomly Forced Shearing Waves
• On the viability of the shearing box approximation for numerical studies of MHD turbulence in accretion disks
• Periodic magnetorotational dynamo action as a prototype of nonlinear magnetic field generation in shear flows
• On the self-sustained nature of large-scale motions in turbulent Couette flow
• Numerical experiments on dynamo action in sheared and rotating turbulence
• Supercriticality to subcriticality in dynamo transitions
• On the Nature of Magnetic Turbulence in Rotating, Shearing Flows
• Subcritical dynamo bifurcation in the Taylor Green flow
• Statistical simulation of the magnetorotational dynamo
• Magnetorotational instability and dynamo action in gravitoturbulent astrophysical discs
• Subcritical dynamos in shear flows
• Dissipative effects on the sustainment of a magnetorotational dynamo in Keplerian shear flow
• Magnetorotational dynamo chimeras. The missing link to turbulent accretion disk dynamo models?
• Supertransient magnetohydrodynamic turbulence in Keplerian shear flows
• Observation of axisymmetric standard magnetorotational instability in the laboratory
• Large scale dynamo action precedes turbulence in shearing box simulations of the magnetorotational instability
• Localized magnetorotational instability and its role in the accretion disc dynamo
• MRI turbulence in accretion discs at large magnetic Prandtl numbers
• Magnetorotational instability with smoothed particle hydrodynamics
• Simple advecting structures and the edge of chaos in subcritical tokamak plasmas
• The edge as a Lagrangian Coherent Structure in a high-dimensional state space
• Dynamo quenching due to shear flow
• Magnetorotational Dynamo Action in the Shearing Box
• The Magnetorotational Instability Prefers Three Dimensions
• A non-local magneto-curvature instability in a differentially rotating disk
• Onset of Plasmoid Reconnection during Magnetorotational Instability
• A systematic route to subcritical dynamo branches
• High-speed shear driven dynamos. Part 1. Asymptotic analysis
• High-speed shear driven dynamos. Part 2. Numerical analysis
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• Magnetorotational instability in a solar near-surface mean-field dynamo
• Impact of magnetic field gradients on the development of the MRI: Applications to binary neutron star mergers and proto-planetary disks
• On nonlinear transitions, minimal seeds and exact solutions for the geodynamo
• Gravitoturbulent dynamo in global simulations of gaseous disks