Viscous resuspension of non-Brownian particles: determination of the concentration profiles and particle normal stresses

We perform local measurements of both the shear rate and the particle fraction to study viscous resuspension in non-Brownian suspensions. A suspension of PMMA spherical particles dispersed in a lighter Newtonian fluid (Triton X100) is sheared in a vertical Couette cell. The vertical profiles of the particle volume fraction are measured for Shields numbers ranging from 10 --3 to 1, and the variation in the particle normal stress in the vorticity direction of the particle fraction is deduced.