Large scale fluctuations and dynamics of the Bullard - von K\'arm\'an dynamo
Fluid Dynamics
2015-05-13 v1
Abstract
A synthetic fluid dynamo built in the spirit of the Bullard device [E. C. Bullard, Proc. Camb. Phil. Soc., 51, 744 (1955)] is investigated. It is a two-step dynamo in which one process stems from the fluid turbulence, while the other part is an alpha effect achieved by a linear amplification of currents in external coils [M. Bourgoin et al., New J. Phys., 8, 329 (2006)]. 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.
Keywords
Cite
@article{arxiv.0906.2719,
title = {Large scale fluctuations and dynamics of the Bullard - von K\'arm\'an dynamo},
author = {Gautier Verhille and Nicolas Plihon and Grégory Fanjat and Romain Volk and Mickael Bourgoin and Jean-François Pinton},
journal= {arXiv preprint arXiv:0906.2719},
year = {2015}
}