Bending oscillations of a cylinder freely falling in still fluid - Institut mécanique des fluides de Toulouse Accéder directement au contenu
Article Dans Une Revue Journal of Fluid Mechanics Année : 2020

Bending oscillations of a cylinder freely falling in still fluid

Résumé

We investigate experimentally the behavior of an elongated flexible cylinder settling at moderate Reynolds number under the effect of buoyancy in a fluid otherwise at rest. The experiments uncover the development of large-amplitude periodic deformations of the cylinder (of the order of its diameter) in specific parameter ranges. Bending oscillations are observed to occur for two base flow situations, involving either a steady or an unsteady wake. In both cases, the sequence of oscillatory deformations emerging when the cylinder length is increased involves the bending modes of an unsupported cylinder with free ends. Comparison of the deformation frequency measured for the falling cylinder with the vortex shedding frequency expected for a non-deformable cylinder at the same Reynolds number indicates that the deformation is coupled to the wake unsteadiness. It also suggests that the cylinder degrees of freedom in deformability allow wake instability to be triggered at Reynolds numbers that would be subcritical for fixed rigid cylinders.
Fichier principal
Vignette du fichier
JFM_R_Cyl_Flex_Production.pdf (1.28 Mo) Télécharger le fichier
Origine : Fichiers produits par l'(les) auteur(s)
Loading...

Dates et versions

hal-02989020 , version 1 (05-11-2020)

Identifiants

Citer

Patricia Ern, Jérôme Mougel, Sébastien Cazin, Manuel Lorite-Díez, Rémi Bourguet. Bending oscillations of a cylinder freely falling in still fluid. Journal of Fluid Mechanics, 2020, 905, ⟨10.1017/jfm.2020.828⟩. ⟨hal-02989020⟩
126 Consultations
107 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More