Ceramics-Silikáty 45, (2) 70 - 75 (2001)

A two-dimensional unsteady mathematical model of particle settling in high-viscosity liquid is presented. The mathematical description of the problem is based on the theory of continua when the presence of solid particles increases the average density of the liquid. To verify this model by laboratory experiments, the settling of monodisperse alumina particles in a high-viscosity liquid was observed. The settling rate was measured as a function of the particle size and concentration. Experimental and calculated data were in acceptable agreement with differences up to 15 rel.%. In addition, the model was used for the simulation of particles accumulation in the cell bottom. The accumulation rate predicted by the model was about 1.5 times higher than the experimental value. The comparison of the mathematical description with laboratory experiments is the first step in the verification procedure of the model for spinel settling during high-level waste vitrification.