REsearch

A gradient of surface tension along an interface between two fluids will set them in motion, a phenomenon known as the Marangoni effect. My colleagues I. Cantat, A. Saint-Jalmes (both in Rennes) and I are interested in the consequences of using water-soluble surface-active molecules to create these flows. Solubility modifies the transport of momentum and mass in the system leading to fascinating connections between macroscopic features (flow size,...) and microscopic properties (solubility,...).

Wetting has been studied for a long time, in particular when the solid of interest is very rigid. My colleagues Julien Dervaux, Laurent Limat and I are interested in what happens when a liquid wets a soft solid (typically a silicone gel). In particular, we investigate the consequences of the deformability of the solid and its ability to dissipate energy alongside that of the liquid on the motion of contact lines, droplets and films.

Granular suspensions are dispersions of solid particles in a liquid in which thermal agitation is negligible. The presence of particles intoduces new characteristic length scales in the material, the particle size and the inter-particle distance. With my colleague Elisabeth Guazzelli, we are interested in suspension flows in thin films. This focus includes the motion of contact lines and sliding droplets. In these cases, the particles experience confinement and volume exclusion, the effect of which on the spreading of the suspensions has received little to no attention.