Rotational dynamics of a soft filament: wrapping transition and propulsive forces

Abstract

We analyze experimentally the shape of a long elastic filament rotating in a viscous liquid. We identify a continuous but sharp transition from a straight to an helical shape, resulting from the competition between viscous stresses and elastic forces. This induced helicity generates a propulsive force along the axis of rotation. In addition, we show that the shape transition is associated with an unstable branch in the force-torque relation. A linearized model of the fluid-structure interaction is proposed to account for all the features of the non-linear filament dynamics.

References in corpus (9)

• Flexive and Propulsive Dynamics of Elastica at Low Reynolds Numbers
• Hydrodynamic flow patterns and synchronization of beating cilia
• Self-organized Beating and Swimming of Internally Driven Filaments
• Trapping and Wiggling: Elastohydrodynamics of Driven Microfilaments
• Experimental Investigations of Elastic Tail Propulsion at Low Reynolds Number
• A macroscopic scale model of bacterial flagellar bundling
• Floppy swimming: Viscous locomotion of actuated elastica
• Propulsion with a Rotating Elastic Nanorod
• Shape transition and propulsive force of an elastic rod rotating in a viscous fluid

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