Experiments in Fluids

, Volume 26, Issue 1, pp 63–74

Influence of a counter rotating vortex pair on the stability of a jet in a cross flow: an experimental study by flow visualizations

  • J. N. Blanchard
  • Y. Brunet
  • A. Merlen

DOI: 10.1007/s003480050265

Cite this article as:
Blanchard, J., Brunet, Y. & Merlen, A. Experiments in Fluids (1999) 26: 63. doi:10.1007/s003480050265

Abstract

 The loss of stability of a flow resulting from the interaction of a transverse jet and a crossflow has been studied experimentally by means of several nonintrusive optical methods (Laser-Induced Fluorescence, Particle Streak Velocimetry). In particular, flow visualizations have allowed measurement of the characteristic velocity of rotation of a counter-rotating vortex pair, which is the prevailing system of this complex flow. It is shown that the elliptical geometry of the cross sections of these vortex structures can cause the loss of stability of the jet according to the theory of Landman and Saffman (1987). The unstable jet state is characterized by the generation of transverse unsteady rotating structures on the jet boundaries. These transverse eddies are clearly identifiable and their regularity of occurrence is satisfactorily explained by the theory of Landman and Saffman. Therefore, this study shows for the first time that the longitudinal structures must be taken into account in the mechanism of stability arising from the meeting of a jet and a cross stream.

Copyright information

© Springer-Verlag Berlin Heidelberg 1999

Authors and Affiliations

  • J. N. Blanchard
    • 1
  • Y. Brunet
    • 2
  • A. Merlen
    • 2
  1. 1.Laboratoire de Combustion et Systèmes Réactifs – C. N. R. S. F-45071 Orléans Cedex 2, FranceFR
  2. 2.Laboratoire de Méchanique de Lille, U.R.A. C.N.R.S. 1441 Bd Paul Langevin, F-59655 Villeneuve d’ascq, FranceFR