The Vorticity Diffusion of Λ-Vortices in Drag Reducing Solutions

Conference paper
Part of the International Union of Theoretical and Applied Mechanics book series (IUTAM)

Abstract

The vorticity diffusion in a Λ -vortex attached to the wall in a complex eigenvalue critical point is investigated. It is shown that extensional viscosity is produced near the critical point. The internal strainfield of the vortex rods is damped and an accelerated vorticity diffusion occurs due to polymer additives.

Some ideas on drag reduction based on such a mechanism are discussed.

Keywords

Vortex Vorticity Macromolecule Nism Shoe 

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References

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Copyright information

© Springer, Berlin Heidelberg 1985

Authors and Affiliations

  • A. Gyr
    • 1
  1. 1.Institute of Hydromechanics and Water Resources ManagementFederal Institute of Technology ETHZZurich-HönggerbergSwitzerland

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