IUCAA Preprints

Permanent URI for this communityhttp://localhost:4000/handle/11007/149

Browse

Filters

20111

Settings

Author: search.filters.author.Subramanian, KandaswamySubject: search.filters.subject.Non-linear

Search Results

Now showing 1 - 1 of 1
  • No Thumbnail Available
    Item
    Hyperdiffusion in non-linear, large and small-scale turbulent dynamos
    (2011-07-05) Subramanian, Kandaswamy
    The generation of large-scale magnetic fields is generically accompanied by the more rapid growth of small-scale fields. The growing Lorentz force due to these fields back reacts on the turbulence to saturate the mean-field and small-scale dynamos. For the mean-field dynamo, in a quasi-linear treatment of this saturation, it is generally thought that, while the alpha-effect gets renormalised and suppressed by non-linear effects, the turbulent diffusion is left unchanged. We show here that this is not true and the effect of the Lorentz forces, is also to generate additional non-linear hyperdiffusion of the mean field. A combination of such non-linear hyperdiffusion with diffusion at small scales, also arises in a similar treatment of small-scale dynamos, and is crucial to understand its saturation.