Advertisement

Imbedded Longitudinal Vortices in Turbulent Boundary Layers

  • R. D. Mehta
  • I. M. M. A. Shabaka
  • P. Bradshaw
Conference paper

Abstract

Sufficiently strong lateral deflection (“skewing”) of the mean streamlines in a shear layer can lead to the generation of discrete longitudinal vortices. The mechanism is basically in viscid, given the presence of an initial shear: this “skew-induced” vorticity should be distinguished from the generation of streamwise vorticity by Reynolds stresses, which is important only in very long, straight streamwise corners and is confined in practice to noncircular ducts. In most cases of practical interest the boundary layer and the imbedded vortex will be turbulent but the decay of the vortex under the action of Reynolds stresses is slow, because its circulation is reduced only by the effect of the spanwise component of skin friction. That is, the skew-induced vortices can influence the flow for a very long distance downstream. The present paper is a description of measurements of the mean and turbulent properties of decaying vortices and vortex pairs; the process of formation (being “ in viscid “) does not require such detailed study as the slow decay. The configurations used are idealizations of those found in practice, but the data should be useful for developing and testing calculation methods intended for reallife cases.

Keywords

Reynolds Stress Turbulent Boundary Layer Eddy Viscosity Vortex Pair Vortex Generator 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Copyright information

© Springer Science+Business Media New York 1982

Authors and Affiliations

  • R. D. Mehta
    • 1
  • I. M. M. A. Shabaka
    • 1
  • P. Bradshaw
    • 1
  1. 1.Department of AeronauticsImperial CollegeLondonUK

Personalised recommendations