Shear-induced self-diffusion in concentrated suspensions

Suspensions consist of solid particles dispersed in a liquid. In practice they are for example used for large-scale transport of particulate materials like sand. During oil and gas drilling suspensions are utilized for the transport of rock cuttings. Furthermore they can be found in industry in the production of foods, paint and paper. Knowledge of the flow properties of suspensions is therefore of practical interest and forms an important research area in rheology. This thesis contains the results of an experimental investigation of ’shear-induced diffusion’. It is by now well-known that individual particles in concentrated suspensions of non-colloidal particles (> 10 μm) exhibit a fluctuating motion under influence of an externally applied flow field. The process can be characterized as diffusion and is caused by the fact that particles on neighbouring streamlines are forced to pass each other. The interactions are asymmetrical and lead to particle displacements.