ConFiG

The sweeping of sand, the anchoring of plant roots in soil or the strengthening of construction materials by fibres are common examples of mechanical interactions between flexible fibres and rigid grains. However, modelling the evolution of the fibres in a moving granular flow is the challenge that the ConFiG project aims at addressing. The difficulty originates from the coupling between the movement of the grains and the shape of the fibre, which results from a balance between the internal elastic forces and the external constrains (mostly friction forces) imposed by the medium. We will work on the fundamental problem of the interactions of a constrained flexible fibre with a granular flow. The ConFiG project will enable the development of theoretical models to predict the configurations of those constrained fibres, a crucial step to better handle mixture of fibres and grains in future processes. The teams will work at the scale of elastic fibres of different mechanical properties and shapes under controlled mechanical load with model experiments and numerical simulations to rationalize such interactions. What is the drag and lift forces on a single fibre in a granular medium? What are the selected shapes in a granular flow? When fibres are arranged in a network, how correlated movements influence the drag forces? Do fibres segregate in a granular flow? We aim at answering those fundamental questions which are the root for future developments.