Full Content is available to subscribers

Subscribe/Learn More  >

Vorticity Dynamics in the Wake of a Yawed Cylinder

[+] Author Affiliations
J. S. Marshall

University of Iowa, Iowa City, IA

Paper No. FEDSM2002-31345, pp. 1151-1156; 6 pages
  • ASME 2002 Joint U.S.-European Fluids Engineering Division Conference
  • Volume 1: Fora, Parts A and B
  • Montreal, Quebec, Canada, July 14–18, 2002
  • Conference Sponsors: Fluids Engineering Division
  • ISBN: 0-7918-3615-0 | eISBN: 0-7918-3600-2
  • Copyright © 2002 by ASME


A theoretical and computational study is reported of the effect of cylinder yaw angle on the vorticity and velocity field in the cylinder wake. Previous experimental studies for yawed cylinder flows conclude that, sufficiently far away from the cylinder ends and for small and moderate values of the yaw angle, the near-wake region is dominated by vortex structures aligned parallel to the cylinder. Associated with this observation, experimentalists have proposed the so-called Independence Principle, which asserts that the forces and vortex shedding frequency of a yawed cylinder are the same as for a cylinder with no yaw using only the component of the free-stream flow oriented normal to the cylinder axis. The current paper examines the structure and consequences for yawed cylinder flows of a quasi-two-dimensional (Q2D) approximation in which the velocity and vorticity have three nonzero components, but have vanishing gradient in the direction of the cylinder axis. In this approximation, the cross-stream velocity field is independent of the axial velocity component, thus reproducing the Independence Principle. Both the axial vorticity and axial velocity components are governed by an advection-diffusion equation. The governing equations for vorticity and velocity in the Q2D theory can be nondimensionalized to eliminate dependence on yaw angle, such that the cross-stream Reynolds number is the only dimensionless parameter. Computations using the Q2D theory are performed to examine the evolution of the cross-stream vorticity and associated axial velocity field. The cross-stream vorticity is observed to shed from the cylinder as thin sheets and to wrap around the Kárman vortex structures, which in turn induces an axial velocity deficit within the wake vortex cores. The computational results indicate two physical mechanisms, associated with instability of the Q2D flow, that might explain the experimentally observed breakdown of the Independence Principle for large yaw angles.

Copyright © 2002 by ASME



Interactive Graphics


Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature

Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal

Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In