Rheometry of visco-plastic fluids

Abstract

This chapter deals with experimental methods for the measurement of the rheological properties of materials, with a focus on yield stress fluids. Section 2 provides the basis of rheometry. Standard equations for viscosimetric flows are given and their application to visco-plastic fluids is discussed. The third section deals with the measurements of the main properties of simple yield stress fluids: solid viscoelastic properties, yield stress, and visco-plastic properties. The fourth section is devoted to the measurements of the properties of thixotropic yield stress fluids, with a focus on the dependence of their behaviour on shear history and on their aging at rest. The phenomena of shear localisation and shear banding are finally discussed in the fifth section, together with possible material inhomogeneities.