Hostname: page-component-cd9895bd7-jn8rn Total loading time: 0 Render date: 2024-12-21T05:23:16.329Z Has data issue: false hasContentIssue false
  • English
  • Français

Structure of a streamwise-oriented vortex incident upon a wing

Published online by Cambridge University Press:  06 March 2017

C. McKenna Open the ORCID record for C. McKenna [Opens in a new window] ,
M. Bross  and
D. Rockwell
C. McKenna*
Affiliation:
Department of Mechanical Engineering, Lehigh University, Bethlehem, PA 18015, USA
M. Bross
Affiliation:
Institute for Fluid Mechanics and Aerodynamics, Bundeswehr University, Werner-Heisenberg-Weg 39, 85577 Neubiberg, Germany
D. Rockwell
Affiliation:
Department of Mechanical Engineering, Lehigh University, Bethlehem, PA 18015, USA
*
†Email address for correspondence: ckm310@lehigh.edu
Get access Rights & Permissions [Opens in a new window]

Abstract

Impingement of a streamwise-oriented vortex upon a fin, tail, blade or wing represents a fundamental class of flow–structure interaction that extends across a range of applications. It can give rise to unsteady loading known as buffeting and to changes of the lift to drag ratio. These consequences are sensitive to parameters of the incident vortex as well as the location of vortex impingement on the downstream aerodynamic surface, generically designated as a wing. Particle image velocimetry is employed to determine patterns of velocity and vorticity on successive cross-flow planes along the vortex, which lead to volume representations and thereby characterization of the streamwise evolution of the vortex structure as it approaches the downstream wing. This evolution of the incident vortex is affected by the upstream influence of the downstream wing, and is highly dependent on the spanwise location of vortex impingement. Even at spanwise locations of impingement well outboard of the wing tip, a substantial influence on the structure of the incident vortex at locations significantly upstream of the leading edge of the wing was observed. For spanwise locations close to or intersecting the vortex core, the effects of upstream influence of the wing on the vortex are to: decrease the swirl ratio; increase the streamwise velocity deficit; decrease the streamwise vorticity; increase the azimuthal vorticity; increase the upwash; decrease the downwash; and increase the root-mean-square fluctuations of both streamwise velocity and vorticity. The interrelationship between these effects is addressed, including the rapid attenuation of axial vorticity in presence of an enhanced defect of axial velocity in the central region of the vortex. When the incident vortex is aligned with, or inboard of, the tip of the wing, the swirl ratio decreases to values associated with instability of the vortex, thereby giving rise to enhanced values of azimuthal vorticity relative to the streamwise (axial) vorticity, as well as relatively large root-mean-square values of streamwise velocity and vorticity.

JFM classification

Aerodynamics: Aerodynamics Vortex Flows: Vortex interactions
Type
Papers
Information
Journal of Fluid Mechanics , Volume 816 , 10 April 2017 , pp. 306 - 330
Check for updates
Copyright
© 2017 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

Adrian, R. J. & Westerweel, J. 2011 Particle Image Velocimetry. Cambridge University Press.Google Scholar
Barnes, C. J., Visbal, M. R. & Gordnier, R. E.2014a Investigation of aeroelastic effects in streamwise-oriented vortex/wing interactions. AIAA Paper 2014-1281.CrossRefGoogle Scholar
Barnes, C. J., Visbal, M. R. & Gordnier, R. E.2014b Numerical simulations of streamwise-oriented vortex/flexible wing interaction. AIAA Paper 2014-2313.Google Scholar
Barnes, C. J., Visbal, M. R. & Gordnier, R. E. 2015a Analysis of streamwise-oriented vortex interactions for two wings in close proximity. Phys. Fluids 27, 015103.Google Scholar
Barnes, C. J., Visbal, M. R. & Huang, G. P.2015b Effect of bending oscillations on a streamwise-oriented vortex interaction. AIAA Paper 2015-3303.Google Scholar
Batchelor, G. K. 1964 Axial flow in trailing line vortices. J. Fluid Mech. 20 (4), 645–658.CrossRefGoogle Scholar
Devenport, W. J., Rife, M. C., Liapis, S. I. & Follin, G. J. 1993 The structure and development of a wing-tip vortex. J. Fluid Mech. 312, 67–106.Google Scholar
Garmann, D. J. & Visbal, M. R.2014a Interactions of a streamwise-oriented vortex with a wing. AIAA Paper 2014-1282.Google Scholar
Garmann, D. J. & Visbal, M. R.2014b Unsteady interactions of a wandering streamwise-oriented vortex with a wing. AIAA Paper 2014-2105.Google Scholar
Garmann, D. J. & Visbal, M. R. 2015a Interactions of a streamwise-oriented vortex with a finite wing. J. Fluid Mech. 767, 782–810.CrossRefGoogle Scholar
Garmann, D. J. & Visbal, M. R.2015b Transient encounters of a NACA 0012 wing with a streamwise-oriented vortex. AIAA Paper 2015-1066.Google Scholar
Garmann, D. J. & Visbal, M. R.2015c Streamwise-oriented vortex interactions with a NACA 0012 wing. AIAA Paper 2015-3073.Google Scholar
Gordnier, R. E. & Visbal, M. R. 1999 Numerical simulation of the impingement of a streamwise vortex on a plate. Intl J. Comput. Fluid Dyn. 12 (1), 49–66.Google Scholar
Gursul, I. & Xie, W. 2001 Interaction of vortex breakdown with an oscillating fin. AIAA J. 39 (3), 438–446.Google Scholar
Hummel, D. 1983 Aerodynamic aspects of formation flight in birds. J. Theor. Biol. 104 (3), 321–347.CrossRefGoogle Scholar
Hummel, D. 1995 Formation flight as an energy-saving mechanism. Isr. J. Zool. 41 (3), 261–278.Google Scholar
Inasawa, A., Mori, F. & Asai, M. 2012 Detailed observations of interactions of wingtip vortices in close-formation flight. J. Aircraft 49 (1), 206–213.Google Scholar
Jacquin, L. & Pantano, C. 2002 On the persistence of trailing vortices. J. Fluid Mech. 471, 159–168.Google Scholar
Kao, D. L., Ahmad, J. U., Holst, T. L. & Allan, D. G.2013 Visualization and analysis of vortex features in helicopter rotor wakes. AIAA Paper 2013-1162.Google Scholar
Kless, J., Aftosmis, M. J., Ning, S. A. & Nemec, M. 2013 Inviscid analysis of extended-formation flight. AIAA J. 51 (7), 1703–1715.Google Scholar
Kroo, I.2004 Innovations in aeronautics. AIAA Paper 2004-0001.Google Scholar
Leibovich, S. & Stewartson, K. 1983 A sufficient condition for the instability of columnar vortices. J. Fluid Mech. 126, 335–356.Google Scholar
Patel, M. H. & Hancock, G. J. 1974 Some experimental results of the effect of a streamwise vortex on a two-dimensional wing. Aeronaut. J. 78, 151–155.Google Scholar
Raffel, M., Steelhorst, U. & Willert, C. 1998 Vortical flow structures at a helicopter rotor model measured by LDV and PIV. Aeronaut. J. 102 (1014), 221–227.Google Scholar
Rockwell, D. 1998 Vortex-body interactions. Annu. Rev. Fluid Mech. 30, 199–229.CrossRefGoogle Scholar
Wittmer, K. S. & Devenport, W. J. 1999 Effects of perpendicular blade-vortex interaction, part 1: turbulence structure and development. AIAA J. 37 (7), 805–812.CrossRefGoogle Scholar
Wolfe, S., Lin, J. C. & Rockwell, D. 1999 Buffeting at the leading-edge of a flat plate due to a streamwise vortex: flow structure and surface pressure loading. J. Fluids Struct. 9, 359–370.Google Scholar
Zheng, Y. & Ramaprian, B. R.1993 An experimental study of wing tip vortex in the near wake of a rectangular wing. US Army Research Office Rep. No. MME-TF-93-1. Washington State University.Google Scholar