Influence of turbulence on the dynamo threshold.
نویسندگان
چکیده
We use direct and stochastic numerical simulations of the magnetohydrodynamic equations to explore the influence of turbulence on the dynamo threshold. In the spirit of the Kraichnan-Kazantsev model, we model the turbulence by a noise, with given amplitude, injection scale, and correlation time. The addition of a stochastic noise to the mean velocity significantly alters the dynamo threshold and increases it for any noise at large scale. For small-scale noise, the result depends on its correlation time and on the magnetic Prandtl number.
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ar X iv : p hy si cs / 0 60 10 62 v 1 1 0 Ja n 20 06 Influence of turbulence on the dynamo threshold
We use direct and stochastic numerical simulations of the magnetohydrodynamic equations to explore the influence of turbulence on the dynamo threshold. In the spirit of the Kraichnan-Kazantsev model, we model the turbulence by a noise, with given amplitude, injection scale and correlation time. The addition of a stochastic noise to the mean velocity significantly alters the dynamo threshold. Wh...
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ورودعنوان ژورنال:
- Physical review letters
دوره 96 20 شماره
صفحات -
تاریخ انتشار 2006