Tunable fall velocity of a dense ball in oscillatory cross-sheared concentrated suspensions

Tunable fall velocity of a dense ball in oscillatory cross-sheared concentrated suspensions

Microstructure in sheared non-Brownian concentrated suspensions

The shear-induced microstructure in non-Brownian suspensions is studied. The Pair Distribution Function in the shear plane is experimentally determined for particle volume fractions ranging from 0.05 to 0.56. Transparent suspensions made of PMMA particles (172μm in diameter) dispersed in a fluorescent index matched Newtonian liquid is sheared in a wide gap Couette rheometer. A thin laser sheet ...

Microstructure and velocity fluctuations in sheared suspensions

The velocity fluctuations present in macroscopically homogeneous suspensions of neutrally buoyant, non-Brownian spheres undergoing simple shear flow, and their dependence on the microstructure developed by the suspensions, are investigated in the limit of vanishingly small Reynolds numbers using Stokesian dynamics simulations. We show that, in the dilute limit, the standard deviation of the vel...

Self-diffusion in sheared suspensions

Self-diffusion in a suspension of spherical particles in steady linear shear flow is investigated by following the time evolution of the correlation of number density fluctuations. Expressions are presented for the evaluation of the self-diffusivity in a suspension which is either macroscopically quiescent or in linear flow at arbitrary Peclet number Pe = j a 2 / 2 D , where j i s the shear rat...

Rheological Measurement of Concentrated Pulp Fiber Suspensions in Oscillatory Shear Using a Novel Device

This paper presents a novel device based on an oscillating torsion resonator with continuously varying frequency capability to characterize the rheological properties of pulp fiber suspensions in a concentrated regime. Fiber suspensions made from unbleached wheat straw pulp at concentrations ranging from 5 wt% to 15 wt% were used. Pulp suspensions exhibit shear-thinning behavior up to a limited...