Quantification of shear viscosity and wall slip velocity of highly concentrated suspensions with non-Newtonian matrices in pressure driven flows

Abstract The rheological characterization of concentrated suspensions is complicated by the heterogeneous nature their flow. In this contribution, shear viscosity and wall slip velocity are quantified for highly (solid volume fractions 0.55–0.60, D 4,3 ~ 5 µm). was determined using a high-pressure capillary rheometer equipped with 3D-printed die that has grooved surface internal flow channel. then calculated from difference between apparent rates through rough smooth die, at identical stress. influence liquid phase rheology on investigated different thickeners, resulting in degrees rate dependency, i.e. indices varied 0.20 1.00. scaled index solid fraction 0.60 showed increasingly large deviations decreasing fraction. It hypothesized these related to shear-induced migration solids macromolecules due stress gradients.