The interaction of two spherical particles in a simple-shear flow of yield stress fluids

We provide acurate measurements of the flow field around a single sphere sheared in a yield stress fluid and discuss the interaction between two spheres, particularly, we show that the fore-aft asymmetry depends on the Deborah number, Bingham number, shear history, initial offset and roughness of the particles. More here 2018_Sarah_2parts.



Mixing resolved beyond the Batchelor scale


Here we present high resolution experiments allowing for the precise quantication of the evolution of concentration distributions of a single lamella experiencing diffusion, stretching and aggregation with other lamellae [2018_Lamella_Souzy].

Revealing the frictional transition in shear thickening suspensions

The sudden and severe increase in the viscosity of certain suspensions above an onset stress is one of the most spectacular phenomena observed in complex fluids.  This shear thickening, which has major implications for industry, is a long-standing puzzle in soft-matter physics.  Recently, a frictional transition was conjectured to cause this phenomenon. Using experimental concepts from granular physics, we provide direct evidences that such suspensions are frictionless under low confining pressure, which is key to understanding their shear thickening behavior. More from PNAS here (2017_PNAS_Clavaud)