Zone settling of concentrated slurries in a centrifugal field.

Theory of batchwise centrifugal casting

“…Submicron-sized particles were used only once before, namely by Sambuichi et al (19911, who used a Hara Gairome Clay. In all studies, good agreement was obtained between experiment and simulation. It must be realized, however, that Sambuichi et al (1987Sambuichi et al ( , 1991 used gravitational settling data to obtain an expression for the sedimentation coefficient s and did not base their model on Stokes' law.…”

“…Because of particle stabilization in suspension, a dense and noncompressible cast develops (Lange and Miller, 1987). Therefore it is not necessary to solve momentum balances over the cast as has been done by Sambuichi et al (1987Sambuichi et al ( , 1991 and Tiller and Hsyung (1993) to describe cast formation from a flocculated suspension.…”

A Strongly Degenerate Convection-diffusion Problem Modeling Centrifugation of Flocculated Suspensions

“…Numerical example. Sambuichi et al [19] published centrifugation experiments with three different flocculent aqueous suspensions, namely of limestone, yeast, and clay, using a cylindrical centrifuge. For each material, the measured gravitational settling rates led to a function 4(^)> and compression data determined a unique effective solid stress function cr e (</>) for each material.…”

“…In this paper, we choose the published data referring to a limestone suspension (see [3] for the case of a clay suspension). Sambuichi et al [19] approximated the measured gravity settling rates for various initial concentrations by three different connecting straight segments in a logarithmic plot, which yields the function …”

“…The parameters and the data that differ in the three cases considered, viz. </> 0 = 0.111 and uj = 146.4 rad/s; (j> 0 = 0.138 and w = 146.4 rad/s; 4> 0 = 0.138 and u = 104.9 rad/s, were chosen in such a way that the simulated supernate-suspension interfaces could be compared with measurements by Sambuichi et al [19], which are shown as open circles (o). While in the compression zone, where <j > > (j) c is valid and hence (16) is parabolic, the solutions are similar to those of the pure gravity case [2,5], there are some distinctive features visible in the hindered settling zone (</> < 4> c ) where (16) is hyperbolic, due to the rotating frame of reference.…”