This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Wake Structure Diagnostics of a Flapping Wing MAV
Technical Paper
2005-01-3198
ISSN: 0148-7191, e-ISSN: 2688-3627
Annotation ability available
Sector:
Language:
English
Abstract
Experiments were performed to better understand the aerodynamic flow field of a flapping-wing micro air vehicle. High-resolution laser sheet flow visualization and particle image velocimetry (PIV) analyses have shown the presence of folded vortex filaments that are trailed from the tip and root of the wing, which are combined with a shed dynamic stall vortex with a strong spanwise flow toward the wing tip. This leading-edge vortex gains strength as the translational motion of the wing accelerates through mid-stroke. There is a subsequent shedding of this vortex, but with the simultaneous formation of another leading-edge vortex. The generation of the second vortex occurs before the first vortex reaches mid-chord, enhancing overall lift. This second vortex moves along the chord during supination, before finally being shed from the trailing-edge of the wing. A starting vortex forms near the trailing-edge as the wing starts to accelerate during the downstroke/upstroke of the flapping cycle. This starting vortex grows larger in size, gaining energy from further shed vortices, until the wing reaches the mid-point of the cycle. The folded root and tip vortices that trail from the flapping wing have been found to be relatively strong, and move inward and axially downward as the wing moves through its flapping cycle. The close proximity of the starting vortex, as well as the trailed root and tip vortices, has a large influence on the downwash over the wing. This suggests that any modeling techniques used to predict the lift on flapping wings must fundamentally take into account the three-dimensional, unsteady effects associated with its complex vortex wake structure.
Recommended Content
Technical Paper | Design of Quiet Efficient Propellers |
Technical Paper | Practical Design of Minimum Induced Loss Propellers |
Technical Paper | Nonlinear Slender Beam-Wise Schemes for Structural Behavior of Flexible UAS Wings |
Authors
Citation
Ramasamy, M., Leishman, J., and Singh, B., "Wake Structure Diagnostics of a Flapping Wing MAV," SAE Technical Paper 2005-01-3198, 2005, https://doi.org/10.4271/2005-01-3198.Also In
References
- Willmott, A. P. Ellington, C. P. Thomas, A. L. R. “Flow Visualization and Unsteady Aerodynamics in the Flight of the Hawkmoth, Manduca Sexta,” Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences 352 No. 1351 March 1997 303 316
- Srygley, R. B. Thomas, A. L. R. “Unconventional Lift-Generating Mechanisms in Free-Flying Butterflies,” Nature 420 Dec. 2002 660 662
- Buckholz, R. H. “Measurements of Unsteady Periodic Forces Generated by the Blowfly Flying in Wind Tunnel,” The Journal of Experimental Biology 90 1981 163 173
- Zanker, J. M. Gotz, K. G. “The Wing Beat of Drosophila Melanogaster II. Dynamics,” Philosophical Transactions of Royal Society of London. B 327 1990 19 44
- Maxworthy, T. “Experiments on the Weis-Fogh Mechanism of Lift Generation by Insects in Hovering Flight. Part I. Dynamics of the “Fling”,” Journal of Fluid Mechanics 93 1979 47 63
- Bennett, L. “Clap and Fling Aerodynamics – An Experimental Evaluation,” The Journal of Experimental Biology 69 1977 261 272
- Dickinson, M. H. Lehmann, F. O. Sane, S. P. “Wing Rotation and the Aerodynamic Basis of Insect Flight,” Science 284 No. 5422 1999 1954 1960
- Ellington, C. P. Van den Berg, C. Willmott, A. P. Thomas, A. L. R. “Leading Edge Vortices in Insect Flight,” Nature 384 1996 626 630
- Wang, Z. J. “Two Dimensional Mechanism for Insect Hovering,” Physics Review Letters 85 2000 2216 2219
- Liu, H. Kawachi, K. “A Numerical Study of Insect Flight,” Journal of Computational Physics 146 1998 124 156
- Ellington, C. P. “The Aerodynamics of Hovering Insect Flight. IV. Aerodynamic Mechanisms,” Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences 305 No. 1122 Feb. 1984 79 113
- Zbikowski, R. Knowles, K. Pedersen, C. B. Galinski, C. “Some Aeromechanical Aspects of Insect-Like Flapping Wings in Hover,” Proceedings of the I Mech E Part G Journal of Aerospace Engineering 218 No. 6 389 298 2004
- Laitone, E. V. “Aerodynamic Lift at Reynolds Number Below 7×10 4 ,” AIAA Journal 34 No. 9 Sept. 1996 1941 1942
- Laitone, E. V. “Wind Tunnel Tests of Wings at Reynolds Number Below 70,000,” Experiments in Fluids 23 1997 405 409
- Ho. Steven Nassef. Hany Pornsinsirirak. Nick Tai. Yu-Chong Ho. Chih-Ming “Unsteady Aerodynamics and Flow Control For Flapping Wing Flyers,” Progress in Aerospace Sciences 39 635 681 2003
- Zimmerman, C. H. “Aerodynamic Characteristics of Several Airfoils of Low Aspect Ratio,” NACA Aug. 1935
- Pelletier, A. Mueller, T. J. “Low Reynolds Number Aerodynamics of Low Aspect Ratio Wings,” AIAA Paper 99–3182 1999
- Van den Berg, C. Ellington, C. P. “The Vortex Wake of a ”Hovering” Model Hawkmoth,” Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences 352 No. 1351 Mar. 1997 317 328
- Van den Berg, C. Ellington, C. P. “The Three-Dimensional Leading Edge Vortex of a ”Hovering” Model Hawkmoth,” Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences 352 No. 1351 Mar. 1997 329 340
- Birch, J. M. Dickinson, M. H. “Spanwise Flow and the Attachment of Leading-Edge Vortex on Insect Wings,” Nature 412 No. 6848 2001 729 733
- Ellington, C. P. Usherwood, J. R. “Lift and Drag Characteristics of Rotary and Flapping Wings,” Fixed and Flapping Wing Aerodynamics for Micro-Air Vehicle Applications Thomas, A. Mueller 195 Progress in Aeronautics and Astronautics AIAA Reston, VA 2001 231 248
- Weish-Fogh, T. “Quick Estimates of Flight Fitness in Hovering Animals Including Novel Mechanisms for Lift Production,” The Journal of Experimental Biology 59 1973 169 230
- Sane, S. P. “The Aerodynamics of Insect Flight,” The Journal of Experimental Biology 206 2003 4191 4208
- Birch, J. M. Dickinson, M. H. “The Influence of Wing-Wake Interactions on the Production of Aerodynamic forces in Flapping Flight,” The Journal of Experimental Biology 206 2257 2272 2003
- Tarascio, M. Ramasamy, M. Chopra, I. Leishman, J. G. “Flow Visualization of MAV Scaled Insect Based Flapping Wings in Hover,” Journal of Aircraft 42 No. 2 March 2005 355 360
- Leishman, J. G. Principles of Helicopter Aerodynamics Cambridge University Press New York 2000 9
- Birch, J. M. Dickson, W. B. Dickinson, M. H. “Force Production and Flow Structure of the Leading Edge Vortex on Flapping Wings at High and Low Reynolds Numbers,” The Journal of Experimental Biology 207 1063 1072 2004
- Leishman, J. G. “Measurements of the Aperiodic Wake of a Hovering Rotor,” Experiments in Fluids 25 1998 352 361