Hostname: page-component-cd9895bd7-dk4vv Total loading time: 0 Render date: 2024-12-24T12:50:46.806Z Has data issue: false hasContentIssue false
  • English
  • Français

Dynamics of the wing-tip vortex in the near field of a NACA 0012 aerofoil

Published online by Cambridge University Press:  27 January 2016

C. del Pino ,
J.M. López-Alonso ,
L. Parras  and
R. Fernandez-Feria
J.M. López-Alonso
Affiliation:
University of Málaga, Málaga, Spain
L. Parras
Affiliation:
University of Málaga, Málaga, Spain
R. Fernandez-Feria
Affiliation:
University of Málaga, Málaga, Spain
Get access Rights & Permissions [Opens in a new window]

Abstract

The dynamics of the wing tip vortex in the near-field of a NACA 0012 aerofoil has been analysed by means of flow visualisations in a water tunnel. Different axial distances near the wing up to four chords, Reynolds numbers up to 42,000 and three angles-of-attack are studied to characterise the behaviour of the vortex meandering. The spatio-temporal vortex centre positions show distorted elliptical shapes in a (x,y)-plane. The Reynolds number has no significant influence on the axial evolution of the meandering amplitude. In addition, the flow visualisations obtained with a low speed camera are analysed by the singular value or proper orthogonal decomposition. Thus, the most energetic displacement modes are obtained. The frequency associated to these modes is computed by FFT. In all the cases studied, our results show that the most unstable mode corresponds to the azimuthal wavenumber |n| = 1 in the so-called Kelvin helical modes and the frequency is lower or close to 1Hz.

Type
Research Article
Information
The Aeronautical Journal , Volume 115 , Issue 1166 , April 2011 , pp. 229 - 239
Copyright
Copyright © Royal Aeronautical Society 2011 

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

1. Baker, G.R., Barker, S.J., Bofah, K.K. and Saffman, P.G. Laser anemometer measurements of trailing vortices in water, J Fluid Mech, 1974, 65, p 325.Google Scholar
2. Green, S.I. and Acosta, A.J. Unsteady flow in trailing vortices, J Fluid Mech, 1991, 227, pp 107–134.Google Scholar
3. Fabre, D. and Le Dizes, S. Viscous and inviscid centre modes in the linear stability of vortices: the vicinity of the neutral curves, J Fluid Mech, 2008, 603, pp 1–38.Google Scholar
4. Devenport, W.J., Rife, M.C., Liapis, S.I. and Follin, G.J. The structure and development of a wing-tip vortex, J Fluid Mech, 1996, 312, pp 67–106.Google Scholar
5. Roy, C. and Leweke, T. Experiments on vortex meandering, 2008, Technical Report TR 1.1.1-4 STREP project no. AST4-CT-2005-012238, Fundamental research on aircraft wake phenomena (FAR-Wake), CNRS-IRPHE.Google Scholar
6. Roy, C. Dynamique et Stabilité de Tourbillons avec Écoulement Axial, 2008, PhD thesis, Université de Provence Aix-Marseille I, Marseille France.Google Scholar
7. Bailey, S.C.C. and Tavoularis, S. Measurements of the velocity field of a wing-tip vortex, wandering in grid turbulence, J Fluid Mech, 2008, 601, pp 281–315.Google Scholar
8. Beresh, S.J., Henfling, J.F. and Spillers, R.W. Meander of a fin trailing vortex and the origin of its turbulence, Exp in Fluids, 2010.Google Scholar
9. Lee, H.W. and Huang, R.F. Frequency selection of wake flow behind a NACA0012 wing, J Marine Sci Tech, 1998, 6, (1), p 29.Google Scholar
10. Heyes, A.L. and Smith, D.A.R. Spatial evolution of a wing-tip vortex using pulsed span-wise jets, Exp in Fluids, 2004, 37, p 120.Google Scholar
11. Abbott, I.H. and Von Doenhoff, A.E. Theory of Wing Sections, Dover publications.Google Scholar
12. Spalart, P. Airplane training vortices, Ann Rev Fluid Mech, 1998, 30, pp 107–138.Google Scholar
13. Parras, L. and Fernandez-Feria, R. Spatial stability and the onset of absolute instability of Batchelor vortex for high swirl numbers, J Fluid Mech, 2007, 583, pp 27.Google Scholar
14. del Pino, C., Parras, L., Felli, M. and Fernandez-Feria, R. PIV measurements of the structure of wing-tip trailing vortices and their comparison with theoretical models, 2010, 15th International Symposium on Applications of Laser Techniques to Fluid Mechanics, Lisbon, Portugal.Google Scholar
15. Antowiak, A. and Brancher, P. Transient energy growth for the Lamb-Oseen vortex, Phys Fluids, 2004, 16, (1).Google Scholar
16. Antowiak, A. and Brancher, P. On vortex rings around vortices: an optimal mechanism, J Fluid Mech, 2007, 578, pp 295–304.Google Scholar
17. Fontane, J., Brancher, P. and Fabre, D. Stochastic forcing of the Lamb Oseen vortex. J Fluid Mech, 2008, 613, p 233.Google Scholar
18. White, F.M. Fluid Mechanics, 2005, Fifth edition, McGraw-Hill, New York.Google Scholar
19. Berkooz, G., Holmes, P. and Lumley, J.L. The proper orthogonal decomposition in the analysis of turbulent flows, Ann Rev Fluid Mech, 1993, 25, pp 539–575.Google Scholar
20. Saad, Y. Iterative Methods for Sparse Linear Systems, 2003, Second ed.ition, SIAM, Philadelphia, USA.Google Scholar