Mickaël Le Fur | Searcharxiv

arXiv2024

A device for studying elementary plasticity fluctuations in granular media

In this manuscript, we describe a scientific device specifically designed for the study of the plasticity fluctuations preceding the fracture of granular media. Biaxial tests on model granular media are performed using a commercial uniaxial loading system. Strain field fluctuations are measured using a method based on the interference of coherent light scattered by the sample. We show that such a device enables discrete plasticity events to be unambiguously evidenced. Moreover, those discrete plasticity fluctuations depend only on the imposed strain, and not on the strain rate.

cond-mat.soft↗

arXiv2019

Dynamical coupling between connected foam films by interface transfer across the menisci

The highly confined flow of the liquid phase, trapped between the gas bubbles, is at the origin of the large effective viscosity of the liquid foams. Despite the industrial relevance of this complex fluid, the foam viscosity remains difficult to predict, because of the lack of flow characterization at the bubble scale. Using an original deformable frame, we provide the first experimental evidence of the interface transfer between a compressed film (resp. a stretched film) and its first neighbour, across their common meniscus. We measure this transfer velocity, which is a key boundary condition for local flows in foams. We also show the dramatic film thickness variation induced by this interface transfer, which may play an important role in the film thickness distribution of a 3D foam sample.

cond-mat.soft↗