Hostname: page-component-cd9895bd7-hc48f Total loading time: 0 Render date: 2024-12-20T20:15:10.751Z Has data issue: false hasContentIssue false
  • English
  • Français

Secondary vortices in the wake of circular cylinders

Published online by Cambridge University Press:  21 April 2006

T. Wei  and
C. R. Smith
T. Wei
Affiliation:
Department of Mechanical Engineering and Mechanics, Lehigh University, Bethlehem, PA 18015, USA
C. R. Smith
Affiliation:
Department of Mechanical Engineering and Mechanics, Lehigh University, Bethlehem, PA 18015, USA
Get access Rights & Permissions [Opens in a new window]

Abstract

Using both the hydrogen-bubble flow-visualization technique and hot-wire-anemometry measurements, secondary vortices have been detected in the near-wake of circular cylinders and their characteristics studied over a Reynolds-number range of 1200–11000. The vortex-shedding characteristics of these secondary vortices clearly indicate that ‘transition waves’, detected in the cylinder near wake by Bloor (1964), and secondary vortices are identical phenomena. It is established that the non-dimensional shedding frequency of the secondary vortices demonstrates a 0.87 power-law relationship relative to Reynolds number, contrary to the 0.5 power-law reported by Bloor. The results suggest that the vortices result from a near-wake, free-shear instability which causes the separated cylinder boundary layer to roll up into the secondary vortices. Visual observations indicate that immediately following their formation the vortices undergo a strong three-dimensional distortion, which may provide the mechanism for the transition from laminar to turbulent Strouhal vortices.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 169 , August 1986 , pp. 513 - 533
Copyright
© 1986 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Bearman, P. W. 1965 Investigation of the flow behind a two-dimensional model with a blunt trailing edge and fitted with splitter plates. J. Fluid Mech. 21, 241–255.Google Scholar
Bernal, L. P. 1981 The coherent structure of turbulent mixing layers. I. Similarity of the primary vortex structure. II. Secondary streamwise vortex structure. Ph.D. thesis, California Institute of Technology, Pasadena
Bloor, M. S. 1964 The transition to turbulence in the wake of a circular cylinder. J. Fluid Mech. 19, 290–304.Google Scholar
Breidenthal, R. 1979 Chemically reacting, turbulent shear layer. AIAA J. 17, 310–311.
Browand, F. K. 1965 An experimental investigation of the instability of an incompressible, separated shear layer. MIT Rep. ASRL TR92–4.Google Scholar
Cain, A. B., Reynolds, W. C. & Ferzinger, J. H. 1981 A three-dimensional simulation of transition and early time decaying mixing layer. Stanford University Rep. No. Tf-14.
Freymuth, P. 1966 On transition in a separated laminar boundary layer. J. Fluid Mech. 25, 683–70.Google Scholar
Gerrard, J. H. 1978 The wakes of cylindrical bluff bodies at low Reynolds number. Phil. Trans. R. Soc. Lond. A 288, 351–382.Google Scholar
Hama, F. R. 1963 Progressive deformation of a perturbed line vortex filament. Phys. Fluids 6, 526–534.Google Scholar
Ho, C. M. & Huang, L. S. 1982 Subharmonics and vortex merging in mixing layers. J. Fluid Mech. 119, 443–472.Google Scholar
Ho, C. M. & Huerre, P. 1984 Perturbed free-shear layers. Ann. Rev. Fluid Mech. 16, 365–424.Google Scholar
Ho, C. M. & Nosseir, N. S. 1981 Dynamics of an impinging jet. Part I. The feedback phenomenon. J. Fluid Mech. 105, 119–42.Google Scholar
Konrad, J. H. 1976 An experimental investigation of mixing in two-dimensional turbulent shear flows with applications to diffusion-limited chemical reactions. Project SQUID Tech. Rep. CIT-8-PU.Google Scholar
Lasheras, J. C., Cho, J. S. & Maxworthy, T. 1986 On the origin and evolution of streamwise vortical structures in a plane, free shear layer. J. Fluid Mech. (in press).Google Scholar
Lin, S. J. 1981 The evolution of streamwise vorticity in the free shear layer. Ph.D. thesis, University of California, Berkeley.
Michalke, A. 1965 On spatially growing disturbances in an inviscid shear layer. J. Fluid Mech. 23, 521–544.Google Scholar
Michalke, A. 1969 A note on spatially growing three-dimensional disturbances in a free shear layer. J. Fluid Mech. 38, 765–767.Google Scholar
Michalke, A. & Hermann, G. 1982 On the inviscid instability of a circular jet with external flow. J. Fluid Mech. 114, 343–359.Google Scholar
Neter, J. & Wasserman, W. 1974 Applied Linear Statistical Models. Richard D. Irwin, Inc.
Schlichting, H. 1979 Boundary Layer Theory, 7th edn, pp. 215–216. McGraw-Hill.
Smith, C. R. & Metzler, S. P. 1983 The characteristics of low-speed streaks in the near-wall region of a turbulent boundary layer. J. Fluid Mech. 129, 27–54.Google Scholar
Unal, M. F. & Rockwell, D. O. 1986 On vortex formation from a cylinder. Part I. The initial instability. J. Fluid Mech. (to appear).Google Scholar
Wei, T. & Smith, C. R. 1980 The appearance of axial vortices in vortex shedding from a cylinder. Bull. Am. Phys. Soc. 25, 1092.Google Scholar