Abstract
The effect of the wake of previous strokes on the aerodynamic forces of a flap** model insect wing is studied using the method of computational fluid dynamics. The wake effect is isolated by comparing the forces and flows of the starting stroke (when the wake has not developed) with those of a later stroke (when the wake has developed). The following has been shown. (1) The wake effect may increase or decrease the lift and drag at the beginning of a half-stroke (downstroke or upstroke), depending on the wing kinematics at stroke reversal. The reason for this is that at the beginning of the half-stroke, the wing ``im**es'' on the spanwise vorticity generated by the wing during stroke reversal and the distribution of the vorticity is sensitive to the wing kinematics at stroke reversal. (2) The wake effect decreases the lift and increases the drag in the rest part of the half-stroke. This is because the wing moves in a downwash field induced by previous half-stroke's starting vortex, tip vortices and attached leading edge vortex (these vortices form a downwash producing vortex ring). (3) The wake effect decreases the mean lift by 6%–18% (depending on wing kinematics at stroke reversal) and slightly increases the mean drag. Therefore, it is detrimental to the aerodynamic performance of the flap** wing.
Similar content being viewed by others
References
Dickinson, M.H.: The effects of wing rotation on unsteady aerodynamic performance at low Reynolds numbers. J. Exp. Biol. 192, 179–206 (1994)
Sun, M., Hossein, H.: A study on the mechanism of high-lift generation by an airfoil in unsteady motion at low Reynolds number. Acta Mechanica Sinica 17, 97–114 (2001)
Dickinson, M.H., Lehman, F.O., Sane, S.P.: Wing rotation and the aerodynamic basis of insect flight. Science 284, 1954–1960 (1999)
Sun, M., Tang, J.: Unsteady aerodynamic force generation by a model fruit fly wing in flap** motion. J. Exp. Biol. 205, 55–70 (2002)
Birch, J.M., Dickinson, M.H.: The Influence of wing-wake interactions on the production of aerodynamic forces in flap** flight. J. Exp. Biol. 206, 2257–2272 (2003)
Ellington, C.P.: The aerodynamics of hovering insect flight. III. Kinematics. Phil. Trans. R. Soc. Lond. B 305, 41–78 (2003)
Fry, S.N., Sayaman, R., Dickinson, M.H.: The aerodynamics of free-flight maneuvers in drosophila. Science 300, 495–498 (2003)
Sun, M., Wu, J.H.: Aerodynamic force generation and power requirements in forward flight in a fruit fly with modeled wing motion. J. Exp. Biol. 206, 3065–3083 (2003)
Wu, J.H., Sun, M.: Unsteady aerodynamic forces of a flap** wing. J. of Exp. Biol. 207, 1137–1150 (2004)
Sun, M., Wu, J.H.: Large aerodynamic force generation by a swee** wing at low Reynolds numbers. Acta Mechanica Sinica 20, 24–31 (2004)
Author information
Authors and Affiliations
Corresponding author
Additional information
The project supported by the National Natural Science Foundation of China (10232010) and the National Aeronautic Science Fund of China(03A51049)
The English text was polished by **%20wing%20on%20the%20production%20of%20aerodynamic%20forces&author=Jianghao%20Wu%20et%20al&contentID=10.1007%2Fs10409-005-0064-4©right=Springer-Verlag%20Berlin%20Heidelberg&publication=0567-7718&publicationDate=2005-10-26&publisherName=SpringerNature&orderBeanReset=true">Reprints and permissions
About this article
Cite this article
Wu, J., Sun, M. The influence of the wake of a flap** wing on the production of aerodynamic forces. ACTA MECH SINICA 21, 411–418 (2005). https://doi.org/10.1007/s10409-005-0064-4
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10409-005-0064-4