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arXiv · 0903.5394

Superposition rheology of shear-banding wormlike micelles

P. Ballesta·M. P. Lettinga·S. Manneville
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Abstract

Wormlike micelle solutions are submitted to small-amplitude oscillatory shear superimposed to steady shear in the shear banding regime. By imposing a shear oscillation, the interface between high- and low-shear regions oscillates in time. A two-fluid semi-phenomenological model is proposed for superposition rheology in the shear banding regime, which allows us to extract a characteristic velocity for the interface dynamics from experiments involving only a standard rheometer. Estimates of the stress diffusion coefficient ${\cal D}$ can also be inferred from such superposition experiments. The validity of our model is confirmed by directly recording the interface displacement using ultrasonic velocimetry.

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P. Ballesta, M. P. Lettinga, S. Manneville. 2009-03-31. Superposition rheology of shear-banding wormlike micelles. https://doi.org/10.1122/1.2750665

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