Subcritical dynamo bifurcation in the Taylor Green flow

Abstract

We report direct numerical simulations of dynamo generation for flow generated using a Taylor-Green forcing. We find that the bifurcation is subcritical, and show its bifurcation diagram. We connect the associated hysteretic behavior with hydrodynamics changes induced by the action of the Lorentz force. We show the geometry of the dynamo magnetic field and discuss how the dynamo transition can be induced when an external field is applied to the flow.

4 pages

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Cited by in corpus (19)

• Dynamo theories
• Bistability and hysteresis of dipolar dynamos generated by turbulent convection in rotating spherical shells
• On the lack of universality in decaying magnetohydrodynamic turbulence
• Nonlinear small-scale dynamos at low magnetic Prandtl numbers
• Systematics of the magnetic-Prandtl-number dependence of homogeneous, isotropic magnetohydrodynamic turbulence
• Bistability and chaos in Taylor-Green dynamo
• Supercriticality to subcriticality in dynamo transitions
• Axial dipolar dynamo action in the Taylor-Green vortex
• Subcritical dynamos in shear flows
• Subcritical transition to turbulence of a precessing flow in a cylindrical vessel
• On the two-dimensional state in driven magnetohydrodynamic turbulence
• The dynamics of unforced turbulence at high Reynolds number for Taylor-Green vortices generalized to MHD
• Dynamo Action in a Quasi-Keplerian Taylor-Couette Flow
• Numerical study of impeller-driven von Karman flows via a volume penalization method
• Study on the large scale dynamo transition
• Dynamo Onset as a First-Order Transition: Lessons from a Shell Model for Magnetohydrodynamics
• A systematic route to subcritical dynamo branches
• Dynamo transition in a five-mode helical model
• The role of field correlations on turbulent dissipation