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Experiments in Fluids

, 55:1660 | Cite as

Characteristic length scales for vortex detachment on plunging profiles with varying leading-edge geometry

  • David E. Rival
  • Jochen Kriegseis
  • Pascal Schaub
  • Alexander Widmann
  • Cameron Tropea
Research Article

Abstract

Experiments on leading-edge vortex (LEV) growth and detachment from a plunging profile have been conducted in a free-surface water tunnel. Direct-force and velocity-field measurements have been performed at a Reynolds number of Re = 10,000, a reduced frequency of k = 0.25, and a Strouhal number of St = 0.16, for three varying leading-edge geometries. The leading-edge shape is shown to influence the shear layer feeding the LEV, and thus to some extent the development of the LEV and associated flow topology. This effect in turn influences the arrival time of the rear (LEV) stagnation point at the trailing edge, which, once breached, constitutes a detachment of the LEV. It is found that despite minor phase changes in LEV detachment through leading-edge shape, the position of the trailing edge (chord length) should be chosen as the characteristic length scale for the vortex separation process.

Keywords

Vortex Vorticity Particle Image Velocimetry Shear Layer Strouhal Number 
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.

Notes

Acknowledgments

This project was funded by the Natural Science and Engineering Research Council of Canada (NSERC) and the Deutsche Forschungsgemeinschaft (DFG). The authors gratefully thank Prof. John Foss for the fruitful discussions regarding the topology of this flow.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  • David E. Rival
    • 1
  • Jochen Kriegseis
    • 1
  • Pascal Schaub
    • 1
    • 2
  • Alexander Widmann
    • 2
  • Cameron Tropea
    • 2
  1. 1.Department of Mechanical EngineeringUniversity of CalgaryCalgaryCanada
  2. 2.Center of Smart Interfaces, Institute of Fluid Mechanics and AerodynamicsTechnische Universität DarmstadtDarmstadtGermany

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