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Travelling waves in pipe flow

H. Faisst·B. Eckhardt
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Abstract

A family of three-dimensional travelling waves for flow through a pipe of circular cross section is identified. The travelling waves are dominated by pairs of downstream vortices and streaks. They originate in saddle-node bifurcations at Reynolds numbers as low as 1250. All states are immediately unstable. Their dynamical significance is that they provide a skeleton for the formation of a chaotic saddle that can explain the intermittent transition to turbulence and the sensitive dependence on initial conditions in this shear flow.

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H. Faisst, B. Eckhardt. 2003-10-15. Travelling waves in pipe flow. https://doi.org/10.1103/physrevlett.91.224502

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