Orateur
Description
Granular materials are collections of grains, larger than 100 μm, that interact through collisions or solid friction. They encompass a wide variety of materials and are present in many industrial sectors and natural phenomena (mining, landslides, etc.). In all of them, mechanical processes such as segregation, percolation, and diffusion take place when subjected to an external shear force. Of all of them, the diffusion process of spherical grains is currently a topic of intense research. However, the diffusion of non-spherical particles, and particularly of single fibers in sheared granular medium still presents a lack of research. Therefore, in this work, we experimentally study the diffusivity of a single fiber immersed in a sheared granular flow. Through the calculation of the mean-squared displacement (MSD), we extract the diffusion coefficient of the fiber under different experimental conditions. We observe that the diffusion is influenced by the fiber length, the grain diameter, and the shear rate imposed on the system. We demonstrate that the normalized diffusion coefficient of the fiber is proportional to the ratio of the fiber length and the grain diameter.
