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arXiv · 1311.7418

Inertio-elastic instability of non shear-banding wormlike micelles

Christophe Perge·Marc-Antoine Fardin·Sebastien Manneville
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Abstract

Homogeneous polymer solutions are well-known to exhibit viscoelastic flow instabilities: purely elastic when inertia is negligible, inertio-elastic otherwise. Recently, shear-banding wormlike micelles solutions were also discovered to follow a similar phenomenology. In the shear-banding regime, inertia is usually negligible so only purely elastic flows have been reported. Here, we investigate a non-shear-banding solution where inertia becomes significant, leading to flow patterns akin to the inertio-elastic regime of dilute polymer solutions. We show that the instability follows a supercritical bifurcation and we investigate the structure of the inertio-elastic vortices that develop above onset.

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Christophe Perge, Marc-Antoine Fardin, Sebastien Manneville. 2013-11-28. Inertio-elastic instability of non shear-banding wormlike micelles. https://doi.org/10.1039/c3sm52868e

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