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Flapping Soft Fin Deformation Modeling using Planar Laser-Induced Fluorescence Imaging
Published on: April 28, 2022
Spontaneous symmetry breaking of a hinged flapping filament generates lift
Shervin Bagheri1, Andrea Mazzino, Alessandro Bottaro
1DICCA, University of Genova, Genova, Italy.
Abstract:
Elastic filamentous structures found on swimming and flying organisms are versatile in function, rendering their precise contribution to locomotion difficult to assess. We show in this Letter that a single passive filament hinged on the rear of a bluff body placed in a stream can generate a net lift force without increasing the mean drag force on the body. This is a consequence of spontaneous symmetry breaking in the filament's flapping dynamics. The phenomenon is related to a resonance between the frequency associated with the von Kármán vortex street developing behind the bluff body and the natural frequency of the free bending vibrations of the filament.
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