Localized travelling waves in the asymptotic suction boundary layer

Academic Article

Abstract

  • We present two spanwise-localized travelling-wave solutions in the asymptotic suction boundary layer, obtained by continuation of solutions of plane Couette flow. One of the solutions has the vortical structures located close to the wall, similar to spanwise-localized edge states previously found for this system. The vortical structures of the second solution are located in the free stream far above the laminar boundary layer and are supported by a secondary shear gradient that is created by a large-scale low-speed streak. The dynamically relevant eigenmodes of this solution are concentrated in the free stream, and the departure into turbulence from this solution evolves in the free stream towards the walls. For invariant solutions in free-stream turbulence, this solution thus shows that the source of energy of the vortical structures can be a dynamical structure of the solution itself, instead of the laminar boundary layer.
  • Authors

  • Kreilos, Tobias
  • Gibson, John
  • Schneider, Tobias M
  • Status

    Publication Date

  • May 2016
  • Has Subject Area

    Published In

    Keywords

  • boundary layers
  • nonlinear dynamical systems
  • transition to turbulence
  • Digital Object Identifier (doi)

    Start Page

  • r3
  • Volume

  • 795