1. Heavy flags undergo spontaneous oscillations in flowing water
- Author
-
Jun Zhang, Nicolas Vandenberghe, Michael Shelley, Applied Math Laboratory Courant Institute of Mathematical Sciences (AML - COURANT INSTITUTE), New York University [New York] (NYU), NYU System (NYU)-NYU System (NYU), Institut de Recherche sur les Phénomènes Hors Equilibre (IRPHE), Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-École Centrale de Marseille (ECM), Department of Physics [New York], and Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Water flow ,media_common.quotation_subject ,drapeau ,General Physics and Astronomy ,Inertia ,01 natural sciences ,Instability ,010305 fluids & plasmas ,[SPI.MECA.MEFL]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph] ,Physics::Fluid Dynamics ,symbols.namesake ,[PHYS.MECA.STRU]Physics [physics]/Mechanics [physics]/Structural mechanics [physics.class-ph] ,0103 physical sciences ,Fluid–structure interaction ,[PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph] ,010306 general physics ,Choked flow ,media_common ,Physics ,[PHYS.MECA.VIBR]Physics [physics]/Mechanics [physics]/Vibrations [physics.class-ph] ,[SPI.MECA.VIBR]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Vibrations [physics.class-ph] ,Vortex shedding ,Classical mechanics ,Drag ,[SPI.MECA.STRU]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Structural mechanics [physics.class-ph] ,symbols ,Strouhal number ,couplage fluides-structures ,46.40.-f, 47.20.-k, 87.19.St - Abstract
International audience; By immersing a compliant yet self-supporting sheet into flowing water, we study a heavy, streamlined, and elastic body interacting with a fluid. We find that above a critical flow velocity a sheet aligned with the flow begins to flap with a Strouhal frequency consistent with animal locomotion. This transition is subcritical. Our results agree qualitatively with a simple fluid dynamical model that predicts linear instability at a critical flow speed. Both experiment and theory emphasize the importance of body inertia in overcoming the stabilizing effects of finite rigidity and fluid drag.
- Published
- 2004
- Full Text
- View/download PDF