Magnetic energy spectrum produced by turbulent dynamo: Effect of time irreversibility
نویسندگان
چکیده
We consider the kinematic stage of evolution magnetic field advected by turbulent hydrodynamic flow. use a generalization Kazantsev-Kraichnan model to investigate time irreversible flows. In viscous range scales, infinite-time limit spectrum is power law but its slope more flat than that predicted Kazantsev model. This result agrees with numerical simulations. The rate energy growth slower in time-symmetric case. show for high Prandtl plasma, formation power-law shape takes very long and may never happen because nonlinearity. propose another ansatz describe at finite time.
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ژورنال
عنوان ژورنال: Physics of Fluids
سال: 2022
ISSN: ['1527-2435', '1089-7666', '1070-6631']
DOI: https://doi.org/10.1063/5.0085170