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Spatio-temporal dynamics of wormlike micelles under shear

L. Becu·S. Manneville·A. Colin
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Abstract

Velocity profiles in a wormlike micelle solution (CTAB in D2O) are recorded using ultrasound every 2 s after a step-like shear rate into the shear-banding regime. The stress relaxation occurs over more than six hours and corresponds to the very slow nucleation and growth of the high-shear band. Moreover, oscillations of the interface position with a period of about 50 s are observed during the growth process. Strong wall slip, metastable states and transient nucleation of three-band flows are also reported and discussed in light of previous experiments and theoretical models.

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L. Becu, S. Manneville, A. Colin. 2004-02-09. Spatio-temporal dynamics of wormlike micelles under shear. https://doi.org/10.1103/physrevlett.93.018301

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