spacer gif spacer gif spacer gif spacer gif spacer gif
 QUICK SEARCH:   [advanced]


spacer gif
     Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents    

This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Dickinson, M. H.
Right arrow Articles by Gotz, K. G.
Right arrow Search for Related Content
PubMed
Right arrow Articles by Dickinson, M. H.
Right arrow Articles by Gotz, K. G.

Journal of Experimental Biology, Vol 174, Issue 1 45-64, Copyright © 1993 by Company of Biologists


JOURNAL ARTICLES

UNSTEADY AERODYNAMIC PERFORMANCE OF MODEL WINGS AT LOW REYNOLDS NUMBERS

M. H. Dickinson and K. G. Gotz

The synthesis of a comprehensive theory of force production in insect flight is hindered in part by the lack of precise knowledge of unsteady forces produced by wings. Data are especially sparse in the intermediate Reynolds number regime (10<Re<1000) appropriate for the flight of small insects. This paper attempts to fill this deficit by quantifying the time-dependence of aerodynamic forces for a simple yet important motion, rapid acceleration from rest to a constant velocity at a fixed angle of attack. The study couples the measurement of lift and drag on a two-dimensional model with simultaneous flow visualization. The results of these experiments are summarized below. 1. At angles of attack below 13.5°, there was virtually no evidence of a delay in the generation of lift, in contrast to similar studies made at higher Reynolds numbers. 2. At angles of attack above 13.5°, impulsive movement resulted in the production of a leading edge vortex that stayed attached to the wing for the first 2 chord lengths of travel, resulting in an 80 % increase in lift compared to the performance measured 5 chord lengths later. It is argued that this increase is due to the process of detached vortex lift, analogous to the method of force production in delta-wing aircraft. 3. As the initial leading edge vortex is shed from the wing, a second vortex of opposite vorticity develops from the trailing edge of the wing, correlating with a decrease in lift production. This pattern of alternating leading and trailing edge vortices generates a von Karman street, which is stable for at least 7.5 chord lengths of travel. 4. Throughout the first 7.5 chords of travel the model wing exhibits a broad lift plateau at angles of attack up to 54°, which is not significantly altered by the addition of wing camber or surface projections. 5. Taken together, these results indicate how the unsteady process of vortex generation at large angles of attack might contribute to the production of aerodynamic forces in insect flight. Because the fly wing typically moves only 2-4 chord lengths each half-stroke, the complex dynamic behavior of impulsively started wing profiles is more appropriate for models of insect flight than are steady-state approximations.


This article has been cited by other articles:


Home page
ScienceHome page
F. T. Muijres, L. C. Johansson, R. Barfield, M. Wolf, G. R. Spedding, and A. Hedenstrom
Leading-Edge Vortex Improves Lift in Slow-Flying Bats
Science, February 29, 2008; 319(5867): 1250 - 1253.
[Abstract] [Full Text] [PDF]


Home page
J. Exp. Biol.Home page
Z. J. Wang
Aerodynamic efficiency of flapping flight: analysis of a two-stroke model
J. Exp. Biol., January 15, 2008; 211(2): 234 - 238.
[Abstract] [Full Text] [PDF]


Home page
J. Exp. Biol.Home page
D. Lentink, F. T. Muijres, F. J. Donker-Duyvis, and J. L. van Leeuwen
Vortex-wake interactions of a flapping foil that models animal swimming and flight
J. Exp. Biol., January 15, 2008; 211(2): 267 - 273.
[Abstract] [Full Text] [PDF]


Home page
Proc. Natl. Acad. Sci. USAHome page
D. L. Altshuler, W. B. Dickson, J. T. Vance, S. P. Roberts, and M. H. Dickinson
Short-amplitude high-frequency wing strokes determine the aerodynamics of honeybee flight
PNAS, December 13, 2005; 102(50): 18213 - 18218.
[Abstract] [Full Text] [PDF]


Home page
J. Exp. Biol.Home page
F.-O. Lehmann, S. P. Sane, and M. Dickinson
The aerodynamic effects of wing-wing interaction in flapping insect wings
J. Exp. Biol., August 15, 2005; 208(16): 3075 - 3092.
[Abstract] [Full Text] [PDF]


Home page
Integr. Comp. Biol.Home page
M. H. Dickinson
The Initiation and Control of Rapid Flight Maneuvers in Fruit Flies
Integr. Comp. Biol., April 1, 2005; 45(2): 274 - 281.
[Abstract] [Full Text] [PDF]


Home page
J. Exp. Biol.Home page
M. Sun and Y. Xiong
Dynamic flight stability of a hovering bumblebee
J. Exp. Biol., February 1, 2005; 208(3): 447 - 459.
[Abstract] [Full Text] [PDF]


Home page
J. Exp. Biol.Home page
L. A. Miller and C. S. Peskin
A computational fluid dynamics of `clap and fling' in the smallest insects
J. Exp. Biol., January 15, 2005; 208(2): 195 - 212.
[Abstract] [Full Text] [PDF]


Home page
J. Exp. Biol.Home page
W. B. Dickson and M. H. Dickinson
The effect of advance ratio on the aerodynamics of revolving wings
J. Exp. Biol., November 15, 2004; 207(24): 4269 - 4281.
[Abstract] [Full Text] [PDF]


Home page
J. Exp. Biol.Home page
Z. J. Wang
The role of drag in insect hovering
J. Exp. Biol., November 1, 2004; 207(23): 4147 - 4155.
[Abstract] [Full Text] [PDF]


Home page
J. Exp. Biol.Home page
L. A. Miller and C. S. Peskin
When vortices stick: an aerodynamic transition in tiny insect flight
J. Exp. Biol., September 1, 2004; 207(17): 3073 - 3088.
[Abstract] [Full Text] [PDF]


Home page
J. Exp. Biol.Home page
J. M. Birch, W. B. Dickson, and M. H. Dickinson
Force production and flow structure of the leading edge vortex on flapping wings at high and low Reynolds numbers
J. Exp. Biol., March 1, 2004; 207(7): 1063 - 1072.
[Abstract] [Full Text] [PDF]


Home page
J. Exp. Biol.Home page
J. H. Wu and M. Sun
Unsteady aerodynamic forces of a flapping wing
J. Exp. Biol., March 1, 2004; 207(7): 1137 - 1150.
[Abstract] [Full Text] [PDF]


Home page
J. Exp. Biol.Home page
Z. J. Wang, J. M. Birch, and M. H. Dickinson
Unsteady forces and flows in low Reynolds number hovering flight: two-dimensional computations vs robotic wing experiments
J. Exp. Biol., February 1, 2004; 207(3): 449 - 460.
[Abstract] [Full Text] [PDF]


Home page
J. Exp. Biol.Home page
S. P. Sane
The aerodynamics of insect flight
J. Exp. Biol., December 1, 2003; 206(23): 4191 - 4208.
[Abstract] [Full Text] [PDF]


Home page
J. Exp. Biol.Home page
M. Sun and J. H. Wu
Aerodynamic force generation and power requirements in forward flight in a fruit fly with modeled wing motion
J. Exp. Biol., September 1, 2003; 206(17): 3065 - 3083.
[Abstract] [Full Text] [PDF]


Home page
J. Exp. Biol.Home page
J. M. Birch and M. H. Dickinson
The influence of wing-wake interactions on the production of aerodynamic forces in flapping flight
J. Exp. Biol., July 1, 2003; 206(13): 2257 - 2272.
[Abstract] [Full Text] [PDF]


Home page
J. Exp. Biol.Home page
H. Wang, L. Zeng, H. Liu, and C. Yin
Measuring wing kinematics, flight trajectory and body attitude during forward flight and turning maneuvers in dragonflies
J. Exp. Biol., February 15, 2003; 206(4): 745 - 757.
[Abstract] [Full Text] [PDF]


Home page
J. Exp. Biol.Home page
J. A. Walker
Rotational lift: something different or more of the same?
J. Exp. Biol., December 15, 2002; 205(24): 3783 - 3792.
[Abstract] [Full Text] [PDF]


Home page
Integr. Comp. Biol.Home page
J. A. Walker and M. W. Westneat
Kinematics, Dynamics, and Energetics of Rowing and Flapping Propulsion in Fishes
Integr. Comp. Biol., November 1, 2002; 42(5): 1032 - 1043.
[Abstract] [Full Text] [PDF]


Home page
J. Exp. Biol.Home page
M. Sun and J. Tang
Lift and power requirements of hovering flight in Drosophila virilis
J. Exp. Biol., August 15, 2002; 205(16): 2413 - 2427.
[Abstract] [Full Text] [PDF]


Home page
J. Exp. Biol.Home page
J. R. Usherwood and C. P. Ellington
The aerodynamics of revolving wings I. Model hawkmoth wings
J. Exp. Biol., June 1, 2002; 205(11): 1547 - 1564.
[Abstract] [Full Text] [PDF]


Home page
J. Exp. Biol.Home page
S. P. Sane and M. H. Dickinson
The aerodynamic effects of wing rotation and a revised quasi-steady model of flapping flight
J. Exp. Biol., April 15, 2002; 205(8): 1087 - 1096.
[Abstract] [Full Text] [PDF]


Home page
Integr. Comp. Biol.Home page
J. A. Walker
Functional Morphology and Virtual Models: Physical Constraints on the Design of Oscillating Wings, Fins, Legs, and Feet at Intermediate Reynolds Numbers
Integr. Comp. Biol., April 1, 2002; 42(2): 232 - 242.
[Abstract] [Full Text] [PDF]


Home page
J. Exp. Biol.Home page
M. Sun and J. Tang
Unsteady aerodynamic force generation by a model fruit fly wing in flapping motion
J. Exp. Biol., January 1, 2002; 205(1): 55 - 70.
[Abstract] [Full Text] [PDF]


Home page
J. Exp. Biol.Home page
S. P. Sane and M. H. Dickinson
The control of flight force by a flapping wing: lift and drag production
J. Exp. Biol., January 8, 2001; 204(15): 2607 - 2626.
[Abstract] [Full Text] [PDF]


Home page
ScienceHome page
M. H. Dickinson, F. Lehmann, and S. P. Sane
Wing Rotation and the Aerodynamic Basis of Insect Flight
Science, June 18, 1999; 284(5422): 1954 - 1960.
[Abstract] [Full Text]


Home page
J. Exp. Biol.Home page
C. Ellington
The novel aerodynamics of insect flight: applications to micro-air vehicles
J. Exp. Biol., January 12, 1999; 202(23): 3439 - 3448.
[Abstract] [PDF]


Home page
J. Exp. Biol.Home page
E. Drucker and G. Lauder
Locomotor forces on a swimming fish: three-dimensional vortex wake dynamics quantified using digital particle image velocimetry
J. Exp. Biol., January 9, 1999; 202(18): 2393 - 2412.
[Abstract] [PDF]


Home page
J. Exp. Biol.Home page
C Schilstra and J. Hateren
Blowfly flight and optic flow. I. Thorax kinematics and flight dynamics
J. Exp. Biol., January 6, 1999; 202(11): 1481 - 1490.
[Abstract] [PDF]




© The Company of Biologists Ltd 1993