The viscosity of suspensions of spheres

Particle size distribution, often suggested as a factor influencing the viscosity of suspensions, is considered quantitatively. By an analysis of previously reported data, the viscosity of suspensions of spheres from the lowest to the highest concentration is shown to be described in terms of the viscosity of the pure liquid, the volume fraction of solids, the packed sediment volume of solids, and the geometric standard deviation for the solids.