Numerical simulations of turbulent dynamos
نویسنده
چکیده
Using a periodic box calculation it is shown that, owing to helicity conservation, a large scale field can only develop on a resistive timescale. This behaviour can be reproduced by a mean-field dynamo with α and ηt quenchings that are equally strong and ‘catastrophic’.
منابع مشابه
Advances in Theory and Simulations of Large-Scale Dynamos
Recent analytical and computational advances in the theory of large-scale dynamos are reviewed. The importance of the magnetic helicity constraint is apparent even without invoking mean-field theory. The tau approximation yields expressions that show how the magnetic helicity gets incorporated into mean-field theory. The test-field method allows an accurate numerical determination of turbulent ...
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تاریخ انتشار 2000