[Couches de Shercliff dans un écoulement cylindrique fortement magnétique de Taylor–Couette]
Nous modéliserons l'écoulement axisymétrique de Taylor–Couette en présence d'un champ magnétique axialement périodique, avec un nombre de Hartmann jusqu'à . La géometrie du champ montre des lignes de champ sous forme de couche de Shercliff. On observe des couches de cisaillement lorsque les frontières sont isolantes, tandis que la rotation est excessive ou inversée pour les frontières conductrices. Certaines configurations de champs sont similaires à celles vues sous forme sphérique ; cependant, de nouvelles configurations existent. Enfin, nous découvrirons l'influence de champs azimutaux () sur ces couches et nous montrerons que l'écoulement diminue avec des bords conducteurs, alors qu'il s'accentue pour des frontières isolantes.
We numerically compute the axisymmetric Taylor–Couette flow in the presence of axially periodic magnetic fields, with Hartmann numbers up to . The geometry of the field singles out special field lines on which Shercliff layers form. These are simple shear layers for insulating boundaries, versus super-rotating or counter-rotating layers for conducting boundaries. Some field configurations have previously studied spherical analogs, but fundamentally new configurations also exist, having no spherical analogs. Finally, we explore the influence of azimuthal fields on these layers, and show that the flow is suppressed for conducting boundaries, but enhanced for insulating boundaries.
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Mot clés : Magnétohydrodynamique, Écoulement de Taylor–Couette
Rainer Hollerbach 1 ; Deborah Hulot 1, 2
@article{CRMECA_2016__344_7_502_0, author = {Rainer Hollerbach and Deborah Hulot}, title = {Shercliff layers in strongly magnetic cylindrical {Taylor{\textendash}Couette} flow}, journal = {Comptes Rendus. M\'ecanique}, pages = {502--509}, publisher = {Elsevier}, volume = {344}, number = {7}, year = {2016}, doi = {10.1016/j.crme.2016.02.012}, language = {en}, }
Rainer Hollerbach; Deborah Hulot. Shercliff layers in strongly magnetic cylindrical Taylor–Couette flow. Comptes Rendus. Mécanique, Volume 344 (2016) no. 7, pp. 502-509. doi : 10.1016/j.crme.2016.02.012. https://comptes-rendus.academie-sciences.fr/mecanique/articles/10.1016/j.crme.2016.02.012/
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