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Title: {alpha} Effect in a Family of Chaotic Flows

Abstract

We perform numerical experiments to calculate the kinematic {alpha} effect for a family of maximally helical, chaotic flows with a range of correlation times. We find that the value of {alpha} depends on the structure of the flow, on its correlation time and on the magnetic Reynolds number in a nontrivial way. Furthermore, it seems that there is no clear relation between {alpha} and the helicity of the flow, contrary to what is often assumed for the parametrization of mean-field dynamo models.

Authors:
; ;  [1]
  1. Department of Applied Mathematics, University of Leeds, Leeds LS2 9JT (United Kingdom)
Publication Date:
OSTI Identifier:
20776985
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 96; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevLett.96.034503; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; CHAOS THEORY; CORRELATIONS; HELICITY; MAGNETIC REYNOLDS NUMBER; MEAN-FIELD THEORY

Citation Formats

Courvoisier, Alice, Hughes, David W., and Tobias, Steven M.. {alpha} Effect in a Family of Chaotic Flows. United States: N. p., 2006. Web. doi:10.1103/PhysRevLett.96.034503.
Courvoisier, Alice, Hughes, David W., & Tobias, Steven M.. {alpha} Effect in a Family of Chaotic Flows. United States. doi:10.1103/PhysRevLett.96.034503.
Courvoisier, Alice, Hughes, David W., and Tobias, Steven M.. Fri . "{alpha} Effect in a Family of Chaotic Flows". United States. doi:10.1103/PhysRevLett.96.034503.
@article{osti_20776985,
title = {{alpha} Effect in a Family of Chaotic Flows},
author = {Courvoisier, Alice and Hughes, David W. and Tobias, Steven M.},
abstractNote = {We perform numerical experiments to calculate the kinematic {alpha} effect for a family of maximally helical, chaotic flows with a range of correlation times. We find that the value of {alpha} depends on the structure of the flow, on its correlation time and on the magnetic Reynolds number in a nontrivial way. Furthermore, it seems that there is no clear relation between {alpha} and the helicity of the flow, contrary to what is often assumed for the parametrization of mean-field dynamo models.},
doi = {10.1103/PhysRevLett.96.034503},
journal = {Physical Review Letters},
number = 3,
volume = 96,
place = {United States},
year = {Fri Jan 27 00:00:00 EST 2006},
month = {Fri Jan 27 00:00:00 EST 2006}
}
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