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Summary: Instability mechanisms and transition scenarios of spiral turbulence in Taylor-Couette flow
Alvaro Meseguer,1,* Fernando Mellibovsky,1
Marc Avila,2
and Francisco Marques1
1
Departament de Física Aplicada, Universitat Politècnica de Catalunya, 08034 Barcelona, Spain
2
Max Planck Institute for Dynamics and Self-Organization, 37073 Göttingen, Germany
Received 20 May 2009; published 23 October 2009
Alternating laminar and turbulent helical bands appearing in shear flows between counterrotating cylinders
are accurately computed and the near-wall instability phenomena responsible for their generation identified.
The computations show that this intermittent regime can only exist within large domains and that its spiral
coherence is not dictated by endwall boundary conditions. A supercritical transition route, consisting of a
progressive helical alignment of localized turbulent spots, is carefully studied. Subcritical routes disconnected
from secondary laminar flows have also been identified.
DOI: 10.1103/PhysRevE.80.046315 PACS number s : 47.20.Lz, 47.20.Ft, 47.27.Cn
A comprehensive understanding of turbulent phenomena
necessarily requires a previous explanation of the mecha-
nisms that mediate between laminar and fully disordered
fluid motion. One of the most challenging shear flow prob-
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