Non-axisymmetric instability of shear-banded Taylor-Couette flow

Abstract

Recent experiments show that shear-banded flows of semi-dilute worm-like micelles in Taylor-Couette geometry exhibit a flow instability in the form of Taylor-like vortices. Here we perform the non-axisymmetric linear stability analysis of the diffusive Johnson-Segalman model of shear banding and show that the nature of this instability depends on the applied shear rate. For the experimentally relevant parameters, we find that at the beginning of the stress plateau the instability is driven by the interface between the bands, while most of the stress plateau is occupied by the bulk instability of the high-shear-rate band. Our work significantly alters the recently proposed stability diagram of shear-banded flows based on axisymmetric analysis.

6 pages, 5 figures, main text and supplementary material; accepted to Phys. Rev. Lett

References in corpus (9)

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• Shear banding and flow-concentration coupling in colloidal glasses
• Shear-induced transitions and instabilities in surfactant wormlike micelles
• Interface instability in shear banding flow
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Cited by in corpus (9)

• Shear Banding of Complex Fluids
• Topology, Length Scales and Energetics of Surfactant Micelles
• Dynamics and Scission of Rodlike Cationic Surfactant Micelles in Shear Flow
• Surfactant micelles: model systems for flow instabilities of complex fluids
• Shear-induced structures versus flow instabilities
• Linear stability analysis of purely elastic travelling wave solutions in pressure driven channel flows
• The relationship between viscoelasticity and elasticity
• A mesoscopic model for the rheology of dilute and semidilute solutions of wormlike micelles
• Geometric scaling of elastic instabilities in the Taylor-Couette geometry: A theoretical, experimental and numerical study