Magnetic field reversals in an experimental turbulent dynamo
Fluid Dynamics
2007-05-23 v1
Abstract
We report the first experimental observation of reversals of a dynamo field generated in a laboratory experiment based on a turbulent flow of liquid sodium. The magnetic field randomly switches between two symmetric solutions B and -B. We observe a hierarchy of time scales similar to the Earth's magnetic field: the duration of the steady phases is widely distributed, but is always much longer than the time needed to switch polarity. In addition to reversals we report excursions. Both coincide with minima of the mechanical power driving the flow. Small changes in the flow driving parameters also reveal a large variety of dynamo regimes.
Cite
@article{arxiv.physics/0701076,
title = {Magnetic field reversals in an experimental turbulent dynamo},
author = {M. Berhanu and R. Monchaux and S. Fauve and N. Mordant and F. Petrelis and A. Chiffaudel and F. Daviaud and B. Dubrulle and L. Marie and F. Ravelet and M. Bourgoin and Ph. Odier and J. -F. Pinton and R. Volk},
journal= {arXiv preprint arXiv:physics/0701076},
year = {2007}
}
Comments
5 pages, 4 figures