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Streaky dynamo equilibria persisting at infinite Reynolds numbers

  • Kengo Deguchi (a1)

Abstract

Nonlinear three-dimensional dynamo equilibrium solutions of viscous-resistive magneto-hydrodynamic equations are continued to formally infinite magnetic and hydrodynamic Reynolds numbers. The external driving mechanism of the dynamo is a uniform shear, which constitutes the base laminar flow and cannot support any kinematic dynamo. Nevertheless, an efficient subcritical nonlinear instability mechanism is found to be able to generate large-scale coherent structures known as streaks, for both velocity and magnetic fields. A finite amount of magnetic field generation is identified at the self-consistent asymptotic limit of the nonlinear solutions, thereby confirming the existence of an effective nonlinear dynamo action at astronomically large Reynolds numbers.

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Corresponding author

Email address for correspondence: kengo.deguchi@monash.edu

References

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Streaky dynamo equilibria persisting at infinite Reynolds numbers

  • Kengo Deguchi (a1)

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