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Interface instability in shear banding flow

S. Lerouge·M. Argentina·J. P. Decruppe
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Abstract

We report on the spatio-temporal dynamics of the interface in shear-banding flow of a wormlike micellar system (cetyltrimethylammonium bromide and sodium nitrate in water) during a start-up experiment. Using the scattering properties of the induced structures, we demonstrate the existence of an instability of the interface between bands along the vorticity direction. Different regimes of spatio-temporal dynamics of the interface are indentified along the stress plateau. We build a model based on the flow symetry which qualitatively describes the observed patterns.

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S. Lerouge, M. Argentina, J. P. Decruppe. 2006-01-31. Interface instability in shear banding flow. https://doi.org/10.1103/physrevlett.96.088301

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