Small-scale kinematic dynamo and non-dynamo in inertial-range turbulence.
Autor(a) principal: | |
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Data de Publicação: | 2010 |
Outros Autores: | |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Institucional da UFOP |
Texto Completo: | http://www.repositorio.ufop.br/handle/123456789/1946 |
Resumo: | We investigate the Lagrangian mechanism of the kinematic “fluctuation” magnetic dynamo in turbulent plasma flow at small magnetic Prandtl numbers. The combined effect of turbulent advection and plasma resistivity is to carry infinitely many field lines to each space point, with the resultant magnetic field at that point given by the average over all the individual line vectors. As a consequence of the roughness of the advecting velocity, this remains true even in the limit of zero resistivity. We show that the presence of dynamo effect requires sufficient angular correlation of the passive line-vectors that arrive simultaneously at the same space point. We demonstrate this in detail for the Kazantsev-Kraichnan model of kinematic dynamo with a Gaussian advecting velocity that is spatially rough and white-noise in time. In the regime where dynamo action fails, we also obtain the precise rate of decay of the magnetic energy. These exact results for the model are obtained by a generalization of the “slow-mode expansion” of Bernard, Gaw¸edzki and Kupiainen to non-Hermitian evolution. Much of our analysis applies also to magnetohydrodynamic turbulence. |
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Eyink, Gregory L.Francisco Neto, Antônio2012-12-03T14:01:15Z2012-12-03T14:01:15Z2010EYINK, G. L.; FRANCISCO NETO, A. Small-scale kinematic dynamo and non-dynamo in inertial-range turbulence. New Journal of Physics, v. 12, n.2, p. 023021-1-023021-40, 2010. Disponível em: <http://arxiv.org/pdf/0908.1598.pdf>. Acesso em: 30 nov. 2012.13672630http://www.repositorio.ufop.br/handle/123456789/1946We investigate the Lagrangian mechanism of the kinematic “fluctuation” magnetic dynamo in turbulent plasma flow at small magnetic Prandtl numbers. The combined effect of turbulent advection and plasma resistivity is to carry infinitely many field lines to each space point, with the resultant magnetic field at that point given by the average over all the individual line vectors. As a consequence of the roughness of the advecting velocity, this remains true even in the limit of zero resistivity. We show that the presence of dynamo effect requires sufficient angular correlation of the passive line-vectors that arrive simultaneously at the same space point. We demonstrate this in detail for the Kazantsev-Kraichnan model of kinematic dynamo with a Gaussian advecting velocity that is spatially rough and white-noise in time. In the regime where dynamo action fails, we also obtain the precise rate of decay of the magnetic energy. These exact results for the model are obtained by a generalization of the “slow-mode expansion” of Bernard, Gaw¸edzki and Kupiainen to non-Hermitian evolution. Much of our analysis applies also to magnetohydrodynamic turbulence.Small-scale kinematic dynamo and non-dynamo in inertial-range turbulence.info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articleDisponível sob Licença Creative Commons 3.0, que permite copiar, distribuir e transmitir o trabalho, desde que seja citado o autor e licenciante. Não permite o uso para fins comerciais nem a adaptação desta. Fonte: Sherpa/Romeo <http://www.sherpa.ac.uk/romeo/search.php?issn=1367-2630> Acesso em 10 Dez. 2013.info:eu-repo/semantics/openAccessengreponame:Repositório Institucional da UFOPinstname:Universidade Federal de Ouro Preto (UFOP)instacron:UFOPLICENSElicense.txtlicense.txttext/plain; charset=utf-81748http://www.repositorio.ufop.br/bitstream/123456789/1946/2/license.txt8a4605be74aa9ea9d79846c1fba20a33MD52ORIGINALARTIGO_SmallScaleKinematic.pdfARTIGO_SmallScaleKinematic.pdfapplication/pdf381831http://www.repositorio.ufop.br/bitstream/123456789/1946/1/ARTIGO_SmallScaleKinematic.pdf0cbde609e94d76e67e600828d70d03b9MD51123456789/19462017-01-05 06:55:23.526oai:localhost: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Repositório InstitucionalPUBhttp://www.repositorio.ufop.br/oai/requestrepositorio@ufop.edu.bropendoar:32332017-01-05T11:55:23Repositório Institucional da UFOP - Universidade Federal de Ouro Preto (UFOP)false |
dc.title.pt_BR.fl_str_mv |
Small-scale kinematic dynamo and non-dynamo in inertial-range turbulence. |
title |
Small-scale kinematic dynamo and non-dynamo in inertial-range turbulence. |
spellingShingle |
Small-scale kinematic dynamo and non-dynamo in inertial-range turbulence. Eyink, Gregory L. |
title_short |
Small-scale kinematic dynamo and non-dynamo in inertial-range turbulence. |
title_full |
Small-scale kinematic dynamo and non-dynamo in inertial-range turbulence. |
title_fullStr |
Small-scale kinematic dynamo and non-dynamo in inertial-range turbulence. |
title_full_unstemmed |
Small-scale kinematic dynamo and non-dynamo in inertial-range turbulence. |
title_sort |
Small-scale kinematic dynamo and non-dynamo in inertial-range turbulence. |
author |
Eyink, Gregory L. |
author_facet |
Eyink, Gregory L. Francisco Neto, Antônio |
author_role |
author |
author2 |
Francisco Neto, Antônio |
author2_role |
author |
dc.contributor.author.fl_str_mv |
Eyink, Gregory L. Francisco Neto, Antônio |
description |
We investigate the Lagrangian mechanism of the kinematic “fluctuation” magnetic dynamo in turbulent plasma flow at small magnetic Prandtl numbers. The combined effect of turbulent advection and plasma resistivity is to carry infinitely many field lines to each space point, with the resultant magnetic field at that point given by the average over all the individual line vectors. As a consequence of the roughness of the advecting velocity, this remains true even in the limit of zero resistivity. We show that the presence of dynamo effect requires sufficient angular correlation of the passive line-vectors that arrive simultaneously at the same space point. We demonstrate this in detail for the Kazantsev-Kraichnan model of kinematic dynamo with a Gaussian advecting velocity that is spatially rough and white-noise in time. In the regime where dynamo action fails, we also obtain the precise rate of decay of the magnetic energy. These exact results for the model are obtained by a generalization of the “slow-mode expansion” of Bernard, Gaw¸edzki and Kupiainen to non-Hermitian evolution. Much of our analysis applies also to magnetohydrodynamic turbulence. |
publishDate |
2010 |
dc.date.issued.fl_str_mv |
2010 |
dc.date.accessioned.fl_str_mv |
2012-12-03T14:01:15Z |
dc.date.available.fl_str_mv |
2012-12-03T14:01:15Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
format |
article |
status_str |
publishedVersion |
dc.identifier.citation.fl_str_mv |
EYINK, G. L.; FRANCISCO NETO, A. Small-scale kinematic dynamo and non-dynamo in inertial-range turbulence. New Journal of Physics, v. 12, n.2, p. 023021-1-023021-40, 2010. Disponível em: <http://arxiv.org/pdf/0908.1598.pdf>. Acesso em: 30 nov. 2012. |
dc.identifier.uri.fl_str_mv |
http://www.repositorio.ufop.br/handle/123456789/1946 |
dc.identifier.issn.none.fl_str_mv |
13672630 |
identifier_str_mv |
EYINK, G. L.; FRANCISCO NETO, A. Small-scale kinematic dynamo and non-dynamo in inertial-range turbulence. New Journal of Physics, v. 12, n.2, p. 023021-1-023021-40, 2010. Disponível em: <http://arxiv.org/pdf/0908.1598.pdf>. Acesso em: 30 nov. 2012. 13672630 |
url |
http://www.repositorio.ufop.br/handle/123456789/1946 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.source.none.fl_str_mv |
reponame:Repositório Institucional da UFOP instname:Universidade Federal de Ouro Preto (UFOP) instacron:UFOP |
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Universidade Federal de Ouro Preto (UFOP) |
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UFOP |
institution |
UFOP |
reponame_str |
Repositório Institucional da UFOP |
collection |
Repositório Institucional da UFOP |
bitstream.url.fl_str_mv |
http://www.repositorio.ufop.br/bitstream/123456789/1946/2/license.txt http://www.repositorio.ufop.br/bitstream/123456789/1946/1/ARTIGO_SmallScaleKinematic.pdf |
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repositorio@ufop.edu.br |
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