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arXiv · 1304.0190

Fluctuation dynamo amplified by intermittent shear bursts in convectively driven magnetohydrodynamic turbulence

J. Pratt·A. Busse·W. -C. Mueller
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Abstract

Intermittent large-scale high-shear flows are found to occur frequently and spontaneously in direct numerical simulations of statistically stationary turbulent Boussinesq magnetohydrodynamic (MHD) convection. The energetic steady-state of the system is sustained by convective driving of the velocity field and small-scale dynamo action. The intermittent emergence of flow structures with strong velocity and magnetic shearing generates magnetic energy at an elevated rate over time-scales longer than the characteristic time of the large-scale convective motion. The resilience of magnetic energy amplification suggests that intermittent shear-bursts are a significant driver of dynamo action in turbulent magnetoconvection.

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J. Pratt, A. Busse, W. -C. Mueller. 2013-09-05. Fluctuation dynamo amplified by intermittent shear bursts in convectively driven magnetohydrodynamic turbulence. https://doi.org/10.1051/0004-6361%2F201321613

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