Foam in a two-dimensional Couette shear: a local measurement of bubble deformation

Eric Janiaud; Francois Graner

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arXiv · cond-mat/0306590

Foam in a two-dimensional Couette shear: a local measurement of bubble deformation

Eric Janiaud·Francois Graner

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Abstract

We re-analyse experiments on a foam sheared in a two-dimensional Couette geometry [Debregeas et al. , Phys. Rev. Lett. 87 , 178305 (2001)]. We characterise the bubble deformation by a texture tensor. Our measurements are local in time: they show two regimes, one transient and one stationary. They provide both the average and fluctuations of the anisotropy. Measurements are also local in space: they show that both the deformation and the elastic contribution to the stress field do not localise, varying smoothly across the shear gap. We can thus describe the foam as a continuous medium with elastic properties.

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Eric Janiaud, Francois Graner. 2004-11-26. Foam in a two-dimensional Couette shear: a local measurement of bubble deformation. https://arxiv.org/abs/cond-mat/0306590

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