Exact Coherent Structures in Turbulent Shear Flows
نویسنده
چکیده
Exact coherent structures are three-dimensional, nonlinear traveling wave solutions of the Navier-Stokes equations. These solutions are typically unstable from onset, yet they capture the basic statistical and structural features of low Reynolds number turbulent shear flows remarkably well. These exact coherent structures have now been found in all canonical shear flows: plane Couette, Poiseuille and pipe flow. They are generic for shear flows and exist for both no-slip and stress boundary conditions. Their discovery opens up new avenues for turbulence research and forces a fundamental rethinking of the true nature of turbulence.
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