Hostname: page-component-76d6cb85b7-lrvh5 Total loading time: 0 Render date: 2026-07-21T17:03:41.093Z Has data issue: false hasContentIssue false
  • English
  • Français

Quantitative characteristics of a laminar, unsteady necklace vortex system at a rectangular block-flat plate juncture

Published online by Cambridge University Press:  26 April 2006

C. V. Seal ,
C. R. Smith ,
O. Akin  and
D. Rockwell
C. V. Seal
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
O. Akin
Affiliation:
Department of Mechanical Engineering and Mechanics, Lehigh University, Bethlehem, PA 18015, USA
D. Rockwell
Affiliation:
Department of Mechanical Engineering and Mechanics, Lehigh University, Bethlehem, PA 18015, USA
Get access Rights & Permissions [Opens in a new window]

Abstract

The unsteady laminar necklace vortex system formed at the junction of a rectangular bluff body and a flat plate was studied experimentally using hydrogen bubble flow visualization and particle image velocimetry (PIV). The vortex system was found to exhibit unsteady behaviour similar to that described by other investigators for cylinder-flat plate junctures, and is characterized by the periodic formation of necklace vortices upstream of the body that subsequently break away and advect towards the block. Detailed analysis of PIV measurements on the plane of symmetry indicates that the dominant mechanism for vorticity balance in the vortex system is the cross-cancellation of the vorticity of the necklace vortex with vorticity of opposite sign generated by interaction of the necklace vortex with the approach surface to the body.

Information

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 286 , 10 March 1995 , pp. 117 - 135
Copyright
© 1995 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.)

Article purchase

Temporarily unavailable

References

Adrian, R. J. 1986 Image shifting technique to resolve directional ambiguity in double-pulsed velocimetry. Appl. Opt. 25, 3855–3858.Google Scholar
Adrian, R. J. 1991 Particle-imaging techniques for experimental fluid mechanics. Ann. Rev. Fluid Mech. 23, 261–304.Google Scholar
Baker, C. J. 1979 The laminar horseshoe vortex. J. Fluid Mech. 95 (2), 347–367.Google Scholar
Blevins, R. D. 1990 Flow-Induced Vibrations, 2nd edn., Van Nostrand Reinhold.
Corcoran, T. E. 1992 Control of the wake from a simulated blade by trailing-edge blowing. MS thesis, Department of Mechanical Engineering and Mechanics, Lehigh University.
Greco, J. J. 1990 The flow structure in the vicinity of a cylinder-flat plate junction: flow regimes, periodicity, and vortex interactions. MS thesis, Department of Mechnical Engineering and Mechanics, Lehigh University.
Harvey, J. K. & Perry, F. J. 1971 Flow field produced by trailing vortices in the vicinity of the ground. AIAA J. 9, 1659–1660.Google Scholar
Landreth, C. C. & Adrian, R. 1989 Measurement and refinement of velocity data using high-image-density analysis in particle image velocimetry. Applications of Laser Anemometry to Fluid Mechanics (ed. R. J. Adrian, T. Asauuma, D. F. G. Durão, F. Durst & J. H. Whitelaw). Springer.
Lugt, H. J. 1983 Vortex Flow in Nature and Technology. John Wiley & Sons.
Mason, P. J. & Morton, B. R. 1987 Trailing vortices in the wakes of surface-mounted obstacles. J. Fluid Mech. 175, 247–293.Google Scholar
Norman, R. S. 1972 On obstacle generated secondary flows in laminar boundary layers and transition to turbulence. PhD dissertation, Department of Mechanics/Mechanical and Aerospace Engineering, Illinois Institute of Technology.
Peace, A. J. & Riley, N. 1983 A viscous vortex pair in ground effect. J. Fluid Mech. 129, 409–426.Google Scholar
Peridier, V. J., Smith, F. T. & Walker, J. D. A. 1991 Vortex-induced boundary-layer separation. Part 1. The unsteady limit problem Re → ∞. J. Fluid Mech. 232, 99–131.Google Scholar
Perry, A. E. & Chong, M. S. 1987 A description of eddying motions and flow patterns using critical-point concepts. Ann. Rev. Fluid Mech. 19, 125–155.Google Scholar
Perry, A. E. & Steiner, T. R. 1987 Large-scale vortex structures in turbulent wakes behind bluff bodies. Part 1. Vortex formation processes. J. Fluid Mech. 174, 233–270.Google Scholar
Robinson, S. K. 1991 Coherent motions in the turbulent boundary layer. Ann. Rev. Fluid Mech. 23, 601–639.Google Scholar
Rockwell, D., Magness, C., Towfighi, J., Akin, O. & Corcoran, T. 1993 High image-density particle image velocimetry using laser scanning techniques. Exps Fluids 14, 181–192.Google Scholar
Schwind, R. G. 1962 The three-dimensional boundary layer near a strut. Gas Turbine Lab. Rep. 67, MIT.
Thomas, A. S. W. 1987 The unsteady characteristics of laminar juncture flow. Phys. Fluids 30, 283–285.Google Scholar
Towfighi, J. 1992 Instantaneous structure of vortex breakdown on a delta wing. MS thesis, Lehigh University.
Visbal, M. R. 1991 The laminar horseshoe vortex system formed at a cylinder/plate juncture. AIAA 22nd Fluid Dyn., Plasma Dyn. & Lasers Conf. AIAA 91–1826.
Walker, J. D. A., Smith, C. R., Cerra, A. W. & Doligalski, T. L. 1987 The impact of a vortex ring on a wall. J. Fluid Mech. 181, 99–140.Google Scholar