Transition to turbulence in open flows: what linear and fully nonlinear local and global theories tell us

Jean-Marc Chomaz 1, *
Abstract : Mixing layers, jets, wakes, boundary layers over wings or rotating disks, Poiseuille and Couette flows are examples of open shear flows encountered in many industrial or geophysical situations. These flows develop spatially under the combined action of advection and instabilities and eventually undergo a transition to turbulence. In the eighties, the linear concepts of absolute and convective instability succeeded in predicting some aspects of open shear flow dynamics, but a description of their spatio-temporal development including nonlinear effects and secondary instabilities was lacking and even the very fact that a linear criterion describes so well strongly nonlinear flows remains mysterious. The present work reports on very recent progress elucidating open shear flow dynamics. A fully nonlinear extension of the concepts of absolute and convective instability introduced by Chomaz (Phys. Rev. Lett. 69 (1992) 1931) is recalled in connection with the broader problem of front and pattern selection. These new ideas are first illustrated on simple amplitude equations. Then the fully nonlinear concepts are applied to actual flows such as wakes and mixing layers. Furthermore, new scenarii involving secondary absolute instability are proposed and compared to the dynamics of the rotating disk and mixing layers experiment.
Type de document :
Article dans une revue
European Journal of Mechanics - B/Fluids, Elsevier, 2004, 23 (13), pp.385-399. 〈10.1016/j.euromechflu.2003.10.006〉
Liste complète des métadonnées

Littérature citée [69 références]  Voir  Masquer  Télécharger

https://hal-polytechnique.archives-ouvertes.fr/hal-01025808
Contributeur : Denis Roura <>
Soumis le : vendredi 8 décembre 2017 - 20:54:33
Dernière modification le : mercredi 25 avril 2018 - 10:45:04

Fichier

JMCT.pdf
Fichiers produits par l'(les) auteur(s)

Identifiants

Collections

Citation

Jean-Marc Chomaz. Transition to turbulence in open flows: what linear and fully nonlinear local and global theories tell us. European Journal of Mechanics - B/Fluids, Elsevier, 2004, 23 (13), pp.385-399. 〈10.1016/j.euromechflu.2003.10.006〉. 〈hal-01025808〉

Partager

Métriques

Consultations de la notice

187

Téléchargements de fichiers

6