Toward a Structural Understanding of Turbulent Drag Reduction: Nonlinear Coherent States in Viscoelastic Shear Flows

Philip A. Stone, Fabian Waleffe, and Michael D. Graham

Phys. Rev. Lett. 89, 208301 – Published 24 October 2002

Abstract

Nontrivial steady flows have recently been found that capture the main structures of the turbulent buffer layer. We study the effects of polymer addition on these “exact coherent states” (ECS) in plane Couette flow. Despite the simplicity of the ECS flows, these effects closely mirror those observed experimentally: Structures shift to larger length scales, wall-normal fluctuations are suppressed while streamwise ones are enhanced, and drag is reduced. The mechanism underlying these effects is elucidated. These results suggest that the ECS are closely related to buffer layer turbulence.

Received 11 December 2001

DOI:https://doi.org/10.1103/PhysRevLett.89.208301

Authors & Affiliations

Philip A. Stone¹, Fabian Waleffe², and Michael D. Graham^1,*

¹Department of Chemical Engineering, University of Wisconsin–Madison, Madison, Wisconsin 53706
²Departments of Mathematics and Engineering Physics, University of Wisconsin–Madison, Madison, Wisconsin 53706

^*Electronic address: graham@engr.wisc.edu

Article Text (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand

Issue

Vol. 89, Iss. 20 — 11 November 2002

Reuse & Permissions

Access Options

Author publication services for translation and copyediting assistance advertisement

Physical Review Letters