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Flapping flight is a commonly used mechanism of micro aerial vehicles and insects alike. Dragonflies use their four-winged anatomy to navigate the environment, maneuver around obstacles, and perform other essential flight patterns. The flight performance and aerodynamics of intact flapping wings is well known; however, this study aims to clarify how wing damage affects the flight performance. First, high speed videos of the damaged wing flight, a takeoff performed by a dragonfly, is captured, and subsequently digitally reconstructed to create a three-dimensional model. Second, using an immersed-boundary method (IBM) based incompressible Navier-Stokes direct numerical simulation (DNS) solver, we resolve the aerodynamic forces and wake topology of the dragonfly’s damaged wing flapping flight in high detail. We found that spanwise damage doesn’t cause any detriment to the force capabilities of the damaged wing which is due to increased pitch angles of the damaged wing. As a consequence, fliers with spanwise damaged and intact wings may be able to utilize similar strategies to achieve takeoffs. The wake topology of the wing damaged flight is also examined. This work serves as a baseline for studying the effect of wing damage for flapping flight and could provide useful insights to micro-aerial vehicle (MAV) designers as some degree of wing damage may be an inevitable occurrence for winged fliers.
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Computational study on the gliding flight of a damselfly
Gliding flight is commonly accepted to be a valuable energy-saving mechanism used by natural flyers. In this work, In this work, the gliding flight of a damselfly undergoing was filmed in a large flight enclosure by using three orthogonally arranged and synchronized highspeed cameras. Using a 3D subdivision surface reconstruction methodology, the damselfly’s wing deformation and kinematics were modeled and reconstructed from the high-speed videos. An immersed-boundary-method-based Navier-Strokes equation solver is then employed to compute the aerodynamic performance of damselfly in gliding flight. A comparison between the aerodynamics of solitary wings and the fore-hind wing system suggests that wing-wing interactions can reduce the drag of the forewing and improve its gliding performance. Three Euler angles are employed to define the orientation of the wings in gliding. Parametric studies on these angles are implemented to obtain the optimal orientation of the wings in gliding flight. It is found that the wings with the orientation directly obtained from the experiments achieve the optimal gliding performance among all cases. In addition, vortex structures and surface pressure are also compared and analyzed to better understand the gliding aerodynamics, which can be used for the flight control of flapping wing micro air vehicles.
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- Award ID(s):
- 1931929
- PAR ID:
- 10473212
- Publisher / Repository:
- American Institute of Aeronautics and Astronautics
- Date Published:
- ISBN:
- 978-1-62410-631-6
- Format(s):
- Medium: X
- Location:
- San Diego, CA & Virtual
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.2514/6.2022-0728
