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arXiv · 2110.10499

Fiber buckling in confined viscous flows: an absolute instability described by the Ginzburg-Landau equation

Jean Cappello·Olivia du Roure·François Gallaire·Camille Duprat·Anke Lindner
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Abstract

We explore the dynamics of a flexible fiber transported by a viscous flow in a Hele-Shaw cell of height comparable to the fiber height. We show that long fibers aligned with the flow experience a buckling instability. Competition between viscous and elastic forces leads to the deformation of the fiber into a wavy shape convolved by a Bell-shaped envelope. We characterize the wavelength and phase velocity of the deformation as well as the growth and spreading of the envelope. Our study of the spatio-temporal evolution of the deformation reveals a linear and absolute instability arising from a local mechanism well described by the Ginzburg-Landau equation.

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Jean Cappello, Olivia du Roure, François Gallaire, Camille Duprat, Anke Lindner. 2021-10-20. Fiber buckling in confined viscous flows: an absolute instability described by the Ginzburg-Landau equation. https://doi.org/10.1103/physrevlett.129.074504

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