Collect. Czech. Chem. Commun. 1998, 63, 870-880

Particle Migration in a Helle-Shaw Cell with Non-Parallel Walls

Jana Wichterlová, Ondřej Wein and František Kaštánek

Institute of Chemical Process Fundamentals, Academy of Sciences of the Czech Republic, 165 02 Prague 6-Suchdol, Czech Republic


Motion of a single macroscopic particle in a liquid flowing through a narrow channel with slightly non-parallel walls is studied by a visualization method. The experiment is limited to the region of slight inertia effects, Ar < 500. Three kinematic characteristics of the particle motion in the channel, viz. settling velocity in a still liquid, as well as longitudinal and lateral migration velocities under non-zero flow, are determined and correlated in dependence on the operation parameters. Both the longitudinal characteristics strongly depend on the particle-to-channel size ratio and are only slightly affected by inertia effects. On the other hand, the inertia effects play an essential role in the mechanism of lateral migration.

Keywords: Helle-Shaw cell; Sedimentation; Longitudinal migration; Lateral migration.