PARTICLE MIGRATION IN A HELLE-SHAW CELL WITH NONPARALLEL WALLS

Motion of a single macroscopic particle in a liquid flowing through a narrow channel with slightly non-parallel walls is studied by a visual ization method. The experiment is limited to the region of slight iner tia effects, Ar < 500. Three kinematic characteristics of the particle motion in the channel, viz. settling velocity in a still liquid, as w ell as longitudinal and lateral migration velocities under non-zero fl ow, are determined and correlated in dependence on the operation param eters. Both the longitudinal characteristics strongly depend on the pa rticle-to-channel size ratio and are only slightly affected by inertia effects. On the other hand, the inertia effects play an essential rol e in the mechanism of lateral migration.