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arXiv · 1306.3811

Suppression of the Rayleigh-Plateau instability on a vertical fibre coated with wormlike micelle solutions

François Boulogne·Marc-Antoine Fardin·Sandra Lerouge·Ludovic Pauchard·Frédérique Giorgiutti-Dauphiné
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Abstract

We report on the Rayleigh-Plateau instability in films of giant micelles solutions coating a vertical fibre. We observe that the dynamics of thin films coating the fibre could be very different from the Newtonian or standard Non-Newtonian cases. By varying the concentration of the components of the solutions and depending on the film thickness, we show for the first time that the Rayleigh-Plateau instability can be stabilized using surfactant solutions. Using global rheology and optical visualisations, we show that the development of shear-induced structures is required to stabilize the micellar film along the fibre. Assuming that the viscoelastic properties of the shear-induced state can be described by a simple model, we suggest that, in addition to the presence of shear-induced structures, the latter must have an elastic modulus greater than a critical value evaluated from a linear stability analysis. Finally, our analysis provides a way of estimating the bulk elasticity of the shear-induced state.

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François Boulogne, Marc-Antoine Fardin, Sandra Lerouge, Ludovic Pauchard, Frédérique Giorgiutti-Dauphiné. 2013-06-17. Suppression of the Rayleigh-Plateau instability on a vertical fibre coated with wormlike micelle solutions. https://doi.org/10.1039/c3sm27940e

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