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arXiv · 1601.01227

Travelling-wave solutions bifurcating from relative periodic orbits in plane Poiseuille flow

Subhendu Rawat·Carlo Cossu·François Rincon
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Abstract

Travelling-wave solutions are shown to bifurcate from relative periodic orbits in plane Poiseuille flow at Re = 2000 in a saddle-node infinite period bifurcation. These solutions consist in self-sustaining sinuous quasi-streamwise streaks and quasi- streamwise vortices located in the bulk of the flow. The lower branch travelling-wave solutions evolve into spanwise localized states when the spanwise size Lz of the domain in which they are computed is increased. On the contrary, upper branch of travelling-wave solutions develop multiple streaks when Lz is increased. Upper branch travelling-wave solutions can be continued into coherent solutions of the filtered equations used in large-eddy simulations where they represent turbulent coherent large-scale motions.

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Subhendu Rawat, Carlo Cossu, François Rincon. 2016-01-06. Travelling-wave solutions bifurcating from relative periodic orbits in plane Poiseuille flow. https://doi.org/10.1016/j.crme.2015.12.005

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