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Experiments in Fluids

, Volume 52, Issue 2, pp 511–517 | Cite as

On the stabilization of leading-edge vortices with spanwise flow

  • Heather R. Beem
  • David E. Rival
  • Michael S. Triantafyllou
Research Article

Abstract

The influence of spanwise flow on the development and stabilization of leading-edge vortices (LEVs) on a foil (without rotational acceleration) has been investigated. The plunging swept wing/fin geometry used in this study, characteristic of fish-like tails, has been found to be insufficient in the stabilization of LEVs. Direct force measurements and visualizations, including Particle Image Velocimetry and lead precipitation, show that despite the presence of a strong spanwise flow at higher sweepback angles, the vortex breaks off and convects downstream at the same relative time as found for low sweepback angles, which experience little spanwise contribution. Although the LEV stabilization is insensitive to bulk spanwise flow, the LEV and tip vortex have been observed to maintain a stronger connection with one another at higher sweepback angles. This result implies that despite similar forces developing for low and high sweepback angles alike, the resulting vortex-wake topologies can vary significantly from one another.

Keywords

Vortex Vorticity Particle Image Velocimetry Vortex Line Particle Image Velocimetry Measurement 
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

We would like to thank J. Dahl for his advice regarding the force measurements and lead precipitation visualizations. Also the authors are grateful for the insight and encouragement provided by H. Babinsky on this topic.

References

  1. Birch JM, Dickinson MH (2001) Spanwise flow and the attachment of the leading-edge vortex on insect wings. Nature 412:729–733CrossRefGoogle Scholar
  2. Buchholz JHJ., Smits AJ (2008) The wake structure and thrust performance of a rigid low-aspect-ratio pitching panel. J Fluid Mech 603:331–365zbMATHCrossRefGoogle Scholar
  3. Ellington CP, van den Berg C, Willmott AP, Thomas ALR (1996) Leading-edge vortices in insect flight. Nature 384:626–630CrossRefGoogle Scholar
  4. Henningsson P, Spedding GR, Hedenstrom A (2008) Vortex wake and flight kinematics of a swift in cruising flight in a wind tunnel. J Exp Biol 211:717–730CrossRefGoogle Scholar
  5. Jones AR, Babinsky H (2011) Reynolds number effects on leading-edge vortex development on a waving wing. Exp Fluids 51(1):197–210. doi: 10.1007/s00348-010-1037-3 Google Scholar
  6. Kim D, Gharib M (2010) Experimental study of three-dimensional vortex structures in translating and rotating plates. Exp Fluids 49(1):329–339Google Scholar
  7. Lentink D, Dickinson MH (2009) Rotational accelerations stabilize leading edge vortices on revolving fly wings. J Exp Biol 212:2705–2719CrossRefGoogle Scholar
  8. McCroskey WJ (1982) Unsteady airfoils. Annu Rev Fluid Mech 14:285–311CrossRefGoogle Scholar
  9. Parker K, von Ellenrieder KD, Soria J (2007) Morphology of the forced oscillatory flow past a finite-span wing at low Reynolds number. J Fluid Mech 571:327–357zbMATHCrossRefGoogle Scholar
  10. Polhamus EC (1971) Predictions of vortex-lift characteristics by a leading-edge suction analogy. J Aircraft 8:193–199CrossRefGoogle Scholar
  11. Ol MV, Bernal L, Kang C-K, Shyy W (2009) Shallow and deep dynamic stall for flapping low Reynolds number airfoils. Exp Fluids 46(5):883–901CrossRefGoogle Scholar
  12. Suryadi A, Ishii T, Obi S (2010) Stereo PIV measurement of a finite, flapping rigid plate in hovering condition. Exp Fluids 49(2):447–460CrossRefGoogle Scholar
  13. Triantafyllou MS, Triantafyllou GS, Yue DKP (2000) Hydrodynamics of fishlike swimming. Annu Rev Fluid Mech 32:3353MathSciNetCrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2011

Authors and Affiliations

  • Heather R. Beem
    • 1
  • David E. Rival
    • 1
    • 2
  • Michael S. Triantafyllou
    • 1
  1. 1.Department of Mechanical EngineeringMassachusetts Institute of TechnologyCambridgeUSA
  2. 2.Department of Mechanical and Manufacturing EngineeringUniversity of CalgaryCalgaryCanada

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