Viscosity of Slurry

The viscosity of slurry usually does not take constant value. In usual cases, viscosity decreases as increasing shear rate or the strength of fluid flow, which is referred as “shear thinning.” Highly loaded slurries of very fine particles show not only the non-Newtonian behavior but also time-dependent flow characteristics. Rheological characteristics of certain kinds of suspensions are remarkably and instantaneously changed by applying external electric and magnetic fields. These phenomena are called electrorheological and magnetorheological effects, respectively. Most systems of interest in practical applications are, of course, more complex in view of particle size than the monodisperse suspensions. Although the viscosity for slurries of completely dispersed particles is a unique function of solid volume fraction, the apparent viscosity usually decreases with increasing shear rate. Additionally, the effects of particle size distribution, the shape, and the surface properties of particles on the viscosity of slurry are significant.