G. VERHILLE – 27 Novembre

The transport of deformable objects by a turbulent flow is common in environmental sciences which are interested, for instance, in the dynamics of plankton in the ocean, and in industry, such as the papermaking or textile industries. However most of the fundamental studies focus on rigid particles and the amplitude of the deformations and their influence on the transport of the fibers remain to be explored.

My presentation is focused on the characterization of the deformations of flexible fibres in homogeneous isotropic turbulence. Two main questions will be tackled here: when does a fiber start to be deformed by the flow? And what is the amplitude of these deformations? Answering these questions will allow to draw an analogy with wormlike chain polymer. However, the spatiotemporal correlations of turbulence are responsible of interesting features such as a straightening of long fibers which become statistically less distorted by turbulence as their length increases.