Modeling of particle settling in high viscosity liquid

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 in creases the average density of the liquid. To verify this model by laborato ry experiments, the settling of monodisperse alumina particles in a high-vi scosity liquid was observed. The settling rate was measured as a function o f the particle size and concentration. Experimental and calculated data wer e in acceptable agreement with differences up to 15 rel. %. In addition, th e model was used for the simulation of particles accumulation in the cell b ottom. The accumulation rate predicted by the model was about 1.5 times hig her than the experimental value. The comparison of the mathematical descrip tion with laboratory experiments is the first step in the verification proc edure of the model for spinel settling during high-level waste vitrificatio n.