K-1218 Solidity of concentrated suspensions due to the flow-induced microstructure in squeezing now between a spherical surface and a flat plate

Abstract

We have examined Bingham like property of concentrated suspensions with non-Brownian spheres in a squeezing film flow. Apparent yield stress has been estimated with a very weak squeezing flow between a spherical surface with a large radius of curvature and a flat plate. The apparent yield stress has gap dependence and is larger than that measured with a torsional shear flow between parallel plates. These trends are more remarkable in monodispersed system in particle size. It is expected from these results that the monodispersed suspension generates a highly aligned structure and the influence of elongational deformation of the structure is significant in the squeezing film for the concentrated suspension.