(601d) Cfd Simulations of Low Concentration Particle Distribution in a Viscometer Cup

The rheological data of a two phase suspension shows a transition from shear thinning fluid to shear thickening fluid at a given shear rate when viscosity is measured using a rheometer with a vane geometry impeller. This phenomenon is observed to occur only for low solids concentration suspensions. We postulate that the settling of the solid particles at low shear could be a reason for this rheological behavior. Computational fluid dynamics (CFD) is used to investigate the distribution of solid particles in the suspension. Sawdust particles classified for a controlled size range is the material used in viscosity measurements. Eularian two-phase model is adopted with the k-e turbulence model to simulate the agitation of the particle suspension in the rheometer cup. Examination of particle suspension simulations over a range of rheometer vane shear rates is used to explain the rheological behavior of the suspension.