Séminaire de Mécanique d'Orsay
Jeudi 10 novembre à 14h au FAST
Flow of dense suspensions:
Liquefaction and avalanches, sedimentation and fluidofracturation
Renaud Toussaint
IPGS, CNRS, Université de Strasbourg
 

When fluid pressure gradients rises to sufficiently high levels in porous media, seepage forces can lead to irreversible flow of the solid matrix. This process is unstable, and leads to high permeability channel formation. We will present here experimental and numerical results on this channel formation and the characterization of their dynamics. We will address the following situations:
. Friction in a sheared dense fluid/granular mixture;
. Saffman Taylor like instability: Transition from fingering to fracture during fluid injection in dense grain packing;
. Rayleigh Taylor like instability: mixing and front growth during sedimentation.