Shear rheology of hard-sphere, dispersed, and aggregated suspensions, and filler-matrix composites

Dependence of Sediment Suspension Viscosity on Solid Concentration: A Simple General Equation

“…Some experiments have shown that the exponent of Equation (5) (i.e., Bφ m ) is always approximately two for many suspensions [33,34]. The exact particle concentration (φ m ) at which there is no fluid to lubricate particle motion for a system of particles remains a matter of debate [16,34], and its determination appears to be an open problem. In many experiments, φ m was commonly used as an adjustable parameter, so that Equation (5) can provide an excellent fitting relationship with the experimental data.…”

“…This study focuses on the suspension viscosity. The suspension viscosity, not limited to the sediment mixture, is affected by particle concentration, shear rate, particle shape, particle size distribution and particle deformability [16][17][18]. Among these factors, the dependence of suspension viscosity on the particle concentration is of great interest in the sediment field [2,3,19,20].…”

“…When particle concentrations are high, particle crowding causes hydrodynamic interactions among particles, which results in large positive deviations from the viscosity value of highly concentrated suspensions from Equations (1) and (2) [16].…”

“…Its value varies depending on various factors, such as the variation of particles from mono-size, and the geometric arrangement of particles [16][17][18]. Equations (1)-(3) apply only to the suspension in which non-cohesive particles are suspended.…”

“…Experiments have been performed to study this relationship, and some models have been used to describe it [21][22][23][24][25][26]. However, a simple relationship may not exist because the particle in a suspending medium can Water 2017, 9, 474 2 of 14 be subject to hydrodynamic, Brownian, colloidal force and other effects, which are not easily modelled in a simple form [16,[27][28][29].…”