[Étude linéaire et non linéaire d'une dynamo produite par un forçage de Taylor–Green]
Un écoulement turbulent forçé par un tourbillon de type Taylor–Green, partage de nombreuses propriétés avec l'écoulement de von Kármán dans lequel une dynamo turbulente a été récemment mise en évidence expérimentalement. Nous présentons des résultats récents de dynamos numériques engendrées par des tourbillons de Taylor–Green dans les régimes linéaire et non linéaire. Nous discutons certaines de ses propriétés comme l'influence de la turbulence, le transfert d'énergie entre différentes échelles, la structure du mode neutre, la nature de la bifurcation et les mécanismes de saturation. Nous discutons également le rôle joué par les fluctuations de vitesse sur le seuil de la dynamo.
The Taylor–Green flow is a model flow sharing many properties with the von Kármán flow, in which experimental turbulent dynamo action has recently been achieved. We present here recent numerical results on the Taylor–Green dynamo instability, both in the linear and non-linear regime. Various properties are considered, such as the influence of turbulence, the energy transfer between different scales, the spatial structure of the neutral mode, the nature of the bifurcation and the saturation mechanisms. We also discuss the role of the velocity fluctuations on the dynamo onset.
Mot clés : Dynamo, Magnétohydrodynamique, Turbulence, Taylor–Green
Yannick Ponty 1 ; Pablo D. Mininni 2, 3 ; Jean-Philipe Laval 4 ; Alexandros Alexakis 1, 3 ; Julien Baerenzung 1, 3 ; François Daviaud 5 ; Bérengère Dubrulle 5 ; Jean-François Pinton 6 ; Héléne Politano 1 ; Annick Pouquet 3
@article{CRPHYS_2008__9_7_749_0,
author = {Yannick Ponty and Pablo D. Mininni and Jean-Philipe Laval and Alexandros Alexakis and Julien Baerenzung and Fran\c{c}ois Daviaud and B\'ereng\`ere Dubrulle and Jean-Fran\c{c}ois Pinton and H\'el\'ene Politano and Annick Pouquet},
title = {Linear and non-linear features of the {Taylor{\textendash}Green} dynamo},
journal = {Comptes Rendus. Physique},
pages = {749--756},
publisher = {Elsevier},
volume = {9},
number = {7},
year = {2008},
doi = {10.1016/j.crhy.2008.07.007},
language = {en},
}
TY - JOUR AU - Yannick Ponty AU - Pablo D. Mininni AU - Jean-Philipe Laval AU - Alexandros Alexakis AU - Julien Baerenzung AU - François Daviaud AU - Bérengère Dubrulle AU - Jean-François Pinton AU - Héléne Politano AU - Annick Pouquet TI - Linear and non-linear features of the Taylor–Green dynamo JO - Comptes Rendus. Physique PY - 2008 SP - 749 EP - 756 VL - 9 IS - 7 PB - Elsevier DO - 10.1016/j.crhy.2008.07.007 LA - en ID - CRPHYS_2008__9_7_749_0 ER -
%0 Journal Article %A Yannick Ponty %A Pablo D. Mininni %A Jean-Philipe Laval %A Alexandros Alexakis %A Julien Baerenzung %A François Daviaud %A Bérengère Dubrulle %A Jean-François Pinton %A Héléne Politano %A Annick Pouquet %T Linear and non-linear features of the Taylor–Green dynamo %J Comptes Rendus. Physique %D 2008 %P 749-756 %V 9 %N 7 %I Elsevier %R 10.1016/j.crhy.2008.07.007 %G en %F CRPHYS_2008__9_7_749_0
Yannick Ponty; Pablo D. Mininni; Jean-Philipe Laval; Alexandros Alexakis; Julien Baerenzung; François Daviaud; Bérengère Dubrulle; Jean-François Pinton; Héléne Politano; Annick Pouquet. Linear and non-linear features of the Taylor–Green dynamo. Comptes Rendus. Physique, Volume 9 (2008) no. 7, pp. 749-756. doi : 10.1016/j.crhy.2008.07.007. https://comptes-rendus.academie-sciences.fr/physique/articles/10.1016/j.crhy.2008.07.007/
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