Large-scale fluctuations and dynamics of the Bullard-von Karman dynamo
نویسندگان
چکیده
A synthetic fluid dynamo built in the spirit of the Bullard device [1] is investigated. It is a two-step dynamo in which one process stems from the fluid turbulence, while the other part is achieved by a linear amplification of currents in external coils [2]. Modifications in the forcing are introduced in order to change the dynamics of the flow, and hence the dynamo behavior. Some features, such as on-off intermittency at onset of dynamo action, are very robust. Large scales fluctuations have a significant impact on the resulting dynamo, in particular in the observation of magnetic field reversals.
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