Experiments in Fluids

, Volume 46, Issue 5, pp 811–821 | Cite as

Smoke visualization of free-flying bumblebees indicates independent leading-edge vortices on each wing pair

  • Richard James Bomphrey
  • Graham K. Taylor
  • Adrian L. R. Thomas
Research Article

Abstract

It has been known for a century that quasi-steady attached flows are insufficient to explain aerodynamic force production in bumblebees and many other insects. Most recent studies of the unsteady, separated-flow aerodynamics of insect flight have used physical, analytical or numerical modeling based upon simplified kinematic data treating the wing as a flat plate. However, despite the importance of validating such models against living subjects, few good data are available on what real insects actually do aerodynamically in free flight. Here we apply classical smoke line visualization techniques to analyze the aerodynamic mechanisms of free-flying bumblebees hovering, maneuvering and flying slowly along a windtunnel (advance ratio: −0.2 to 0.2). We find that bumblebees, in common with most other insects, exploit a leading-edge vortex. However, in contrast to most other insects studied to date, bumblebees shed both tip and root vortices, with no evidence for any flow structures linking left and right wings or their near-wakes. These flow topologies will be less efficient than those in which left and right wings are aerodynamically linked and shed only tip vortices. While these topologies might simply result from biological constraint, it is also possible that they might have been specifically evolved to enhance control by allowing left and right wings to operate substantially independently.

Notes

Acknowledgments

Research sponsored by BBSRC Studentship 00A1S06405. RJB is a PD Research Fellow at St Anne’s College, Oxford. GKT is a Royal Society University Research Fellow and RCUK Academic Fellow. The authors are grateful to the BBC for loaning the Phantom high-speed digital video camera.

Supplementary material

348_2009_631_MOESM1_ESM.mov (7.8 mb)
Supplementary material 1 (MOV 7986 kb)

References

  1. Altshuler DL, Dickson WB, Vance JT, Roberts SP, Dickinson MH (2005) Short-amplitude high-frequency wing strokes determine the aerodynamics of honeybee flight. PNAS 102:18213–18218CrossRefGoogle Scholar
  2. Birch JM, Dickinson MH (2001) Spanwise flow and the attachment of the leading-edge vortex on insect wings. Nature 412:729–733CrossRefGoogle Scholar
  3. Bomphrey RJ (2006) Insects in flight: direct visualization and flow measurements. J Bioinsp Biomim 1:S1–S9CrossRefGoogle Scholar
  4. Bomphrey RJ, Lawson NJ, Harding NJ, Taylor GK, Thomas ALR (2005) The aerodynamics of Manduca sexta: digital particle image velocimetry analysis of the leading-edge vortex. J Exp Biol 208:1079–1094CrossRefGoogle Scholar
  5. Bomphrey RJ, Lawson NJ, Taylor GK, Thomas ALR (2006a) Application of digital particle image velocimetry to insect aerodynamics: measurement of the leading-edge vortex and near wake of a Hawkmoth. Exp Fluids 40:546–554CrossRefGoogle Scholar
  6. Bomphrey RJ, Taylor GK, Lawson NJ, Thomas ALR (2006b) Digital particle image velocimetry measurements of the downwash distribution of a desert locust Schistocerca gregaria. J Roy Soc Interface 3:311–317CrossRefGoogle Scholar
  7. Brodsky AK (1994) The evolution of insect flight. Oxford University Press, OxfordGoogle Scholar
  8. Cimbala JM, Nagib HM, Roshko A (1988) Large structure in the far wakes of two-dimensional bluff bodies. J Fluid Mech 190:265–298CrossRefGoogle Scholar
  9. Dabiri JO (2005) On the estimation of swimming and flying forces from wake measurements. J Exp Biol 208:3519–3532CrossRefGoogle Scholar
  10. Délery JM (2001) Robert Legendre and Henri Werlé: toward the elucidation of three-dimensional separation. Annu Rev Fluid Mech 33:129–154CrossRefGoogle Scholar
  11. Demoll R (1918) Der Flug der Insekten und Vögel, vol. 69. Jena, G FischerGoogle Scholar
  12. Demoll R (1919) Zuschriften an die Herausgeber. Der Flug der Insekten und der Vögel. Die Naturwissenschaften 27:480–482CrossRefGoogle Scholar
  13. Dickinson MH, Götz KG (1996) The wake dynamics and flight forces of the fruit fly Drosophila melanogaster. J Exp Biol 199:2085–2104Google Scholar
  14. Dickinson MH, Lehmann F-O, Sane SP (1999) Wing rotation and the aerodynamic basis of insect flight. Science 284:1954–1960CrossRefGoogle Scholar
  15. Dudley R, Ellington CP (1990) Mechanics of forward flight in bumblebees: I. Kinematics and morphology. J Exp Biol 148:19–52Google Scholar
  16. Ellington CP (1984) The aerodynamics of hovering insect flight. III. Kinematics. Phil Trans R Soc Lond B 305:41–78CrossRefGoogle Scholar
  17. Ellington CP, van den Berg C, Willmott AP, Thomas ALR (1996) Leading-edge vortices in insect flight. Nature 384:626–630CrossRefGoogle Scholar
  18. Grodnitsky DL, Morozov PP (1993) Vortex formation during tethered flight of functionally and morphologically two-winged insects, including evolutionary considerations on insect flight. J Exp Biol 182:11–40Google Scholar
  19. Hedenstrom A, Johansson LC, Wolf M, von Busse R, Winter Y, Spedding GR (2007) Bat flight generates complex aerodynamic tracks. Science 316:894–897CrossRefGoogle Scholar
  20. Hoff W (1919) Der Flug der Insekten und der Vögel. Die Naturwissenschaften 10:162–169Google Scholar
  21. Kokshaysky NV (1979) Tracing the wake of a flying bird. Nature 279:146–148CrossRefGoogle Scholar
  22. Lehmann FO (2004) The mechanisms of lift enhancement in insect flight. Naturwissenschaften 91:101–122CrossRefGoogle Scholar
  23. Lehmann FO, Sane SP, Dickinson M (2005) The aerodynamic effects of wing-wing interaction in flapping insect wings. J Exp Biol 208:3075–3092CrossRefGoogle Scholar
  24. Maxworthy T (1979) Experiments on the Weis-Fogh mechanism of lift generation by insects in hovering flight. Part 1. Dynamics of the ‘fling’. J Fluid Mech 93:47–63CrossRefGoogle Scholar
  25. Noca F, Shiels D, Jeon D (1999) A comparison of methods for evaluating time-dependent fluid dynamic forces on bodies, using only velocity fields and their derivatives. J Fluids Struct 13:551–578CrossRefGoogle Scholar
  26. Norberg UM (1976) Aerodynamics, kinematics, and energetics of horizontal flapping flight in the long-eared bat Plecotus auritus. J Exp Biol 65:179–212Google Scholar
  27. Perry AE, Chong MS (1987) A description of eddying motions and flow patterns using critical-point concepts. Annu Rev Fluid Mech 19:125–155CrossRefGoogle Scholar
  28. Ramasamy M, Leishman JG (2006) Phase-locked particle image velocimetry measurements of a flapping wing. J Aircraft 43:1867–1875CrossRefGoogle Scholar
  29. Sane SP (2003) The aerodynamics of insect flight. J Exp Biol 206:4191–4208CrossRefGoogle Scholar
  30. Shyy W, Liu H (2007) Flapping wings and aerodynamic lift: the role of leading-edge vortices. AIAA J 45:2817–2819CrossRefGoogle Scholar
  31. Spedding GR (1986) The wake of a jackdaw (Corvus-Monedula) in slow flight. J Exp Biol 125:287–307Google Scholar
  32. Spedding GR (1987) The wake of a kestrel (Falco tinnunculus) in flapping flight. J Exp Biol 127:59–78Google Scholar
  33. Spedding GR, Rosen M, Hedenstrom A (2003) A family of vortex wakes generated by a thrush nightingale in free flight in a wind tunnel over its entire natural range of flight speeds. J Exp Biol 206:2313–2344CrossRefGoogle Scholar
  34. Srygley RB, Thomas ALR (2002) Unconventional lift-generating mechanisms in free-flying butterflies. Nature 420:660–664CrossRefGoogle Scholar
  35. Swartz S, Galvao R, Iriarte-Diaz J, Israeli E, Middleton K, Roemer R, Tian X, Breuer K (2005) Unique characteristics of aerodynamics of bat flight evidence from direct visualization of patterns of airflow in the wakes of naturally flying bats. Int Comp Biol 45:1080Google Scholar
  36. Thomas ALR, Taylor GK, Srygley RB, Nudds RL, Bomphrey RJ (2004) Dragonfly flight: free-flight and tethered flow visualizations reveal a diverse array of unsteady lift-generating mechanisms, controlled primarily via angle of attack. J Exp Biol 207:4299–4323CrossRefGoogle Scholar
  37. Van den Berg C, Ellington CP (1997) The vortex wake of a ‘hovering’ model hawkmoth. Phil Trans R Soc Lond B 352:317–328CrossRefGoogle Scholar
  38. Videler JJ, Stamhuis EJ, Povel GDE (2004) Leading-edge vortex lifts swifts. Science 306:1960–1962CrossRefGoogle Scholar
  39. Walker JA (2002) Rotational lift: something different or more of the same? J Exp Biol 205:3783–3792Google Scholar
  40. Walker SM, Thomas ALR, Taylor GK (2008) Photogrammetric reconstruction of high-resolution surface topographies and deformable wing kinematics of tethered locusts and free-flying hoverflies. J Roy Soc Interface. doi:10.1098/rsif.2008.0245
  41. Walker SM, Thomas ALR, Taylor GK (2009) Deformable wing kinematics in the desert locust: how and why do camber, twist and topography vary through the stroke? J Roy Soc Interface. doi:10.1098/rsif.2008.0435
  42. Warrick DR, Tobalske BW, Powers DR (2005) Aerodynamics of the hovering hummingbird. Nature 435:1094–1097CrossRefGoogle Scholar
  43. Willmott AP, Ellington CP, Thomas ALR (1997) Flow visualization and unsteady aerodynamics in the flight of the hawkmoth, Manduca sexta. Phil Trans R Soc Lond B 352:303–316CrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  • Richard James Bomphrey
    • 1
  • Graham K. Taylor
    • 1
  • Adrian L. R. Thomas
    • 1
  1. 1.Department of ZoologyOxford UniversityOxfordUK

Personalised recommendations