arXiv 0909.05302009-09-02physics.flu-dyn

Localised edge states nucleate turbulence in extended plane Couette cells

TM Schneider, D Marinc, Bruno Eckhardt

备注：: 15 pages, 5 figures
DOI：: 10.1017/S0022112009993144

英文摘要：

We study the turbulence transition of plane Couette flow in large domains where localised perturbations are observed to generate growing turbulent spots. Extending previous studies on the boundary between laminar and turbulent dynamics we determine invariant structures intermediate between laminar and turbulent flow. In wide but short domains we find states that are localised in spanwise direction, and in wide and long domains the states are also localised in downstream direction. These localised states act as critical nuclei for the transition to turbulence in spatially extended domains.

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