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OJFD> Vol.4 No.4, December 2014
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Aerodynamics of the Cupped Wings during Peregrine Falcon’s Diving Flight

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DOI: 10.4236/ojfd.2014.44027    4,019 Downloads   5,702 Views   Citations
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Benjamin Ponitz, Michael Triep, Christoph Brücker

Affiliation(s)

Institute of Mechanics and Fluid Dynamics, TU Bergakademie Freiberg, Freiberg, Germany.

ABSTRACT

During a dive peregrine falcons can reach velocities of more than 320 km/h and makes themselves the fastest animals in the world. The aerodynamic mechanisms involved are not fully understood yet and the search for a conclusive answer to this fact motivates the three-dimensional (3-D) flow study. Especially the cupped wing configuration which is a unique feature of the wing shape in falcon peregrine dive is our focus herein. In particular, the flow in the gap between the main body and the cupped wing is studied to understand how this flow interacts with the body and to what extend it affects the integral forces of lift and drag. Characteristic shapes of the wings while diving are studied with regard to their aerodynamics using computational fluid dynamics (CFD). The results of the numerical simulations via ICEM CFD and OpenFOAM show predominant flow structures around the body surface and in the wake of the falcon model such as a pair of body vortices and tip vortices. The drag for the cupped wing profile is reduced in relation to the configuration of opened wings (without cupped-like profile) while lift is increased. The purpose of this study is primarily the basic research of the aerodynamic mechanisms during the falcon’s diving flight. The results could be important for maintaining good maneuverability at high speeds in the aviation sector.

KEYWORDS

Peregrine Falcon, Aerodynamics, Cupped Wings, CFD

Conflicts of Interest

The authors declare no conflicts of interest.

Cite this paper

Ponitz, B. , Triep, M. and Brücker, C. (2014) Aerodynamics of the Cupped Wings during Peregrine Falcon’s Diving Flight. Open Journal of Fluid Dynamics, 4, 363-372. doi: 10.4236/ojfd.2014.44027.

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