The movement of a cluster of particles subject to the effect of gravity and their sedimentation onto a plane horizontal surface

A numerical investigation, on the basis of nonstationary two-dimensional equations of the mechanics of heterogeneous media, into the movement mechanisms of a cloud of particles subject to the effect of gravity in an unbounded medium, and into the interaction of the descending cluster of particles with a plane horizontal surface is reported. According to the degree of hydrodynamic interaction between the particles, various conditions of movement are discerned of the cloud which is settling, and the change in its spatial configuration is traced, which is determined by the large-scale vortical movement of the carrier medium which develops. Distributions are obtained of the concentrations of particles on the sedimentation surfaces. A dispersion coefficient for the cluster of particles on the plane horizontal surface is introduced, and its relationship with the concentration of the particles, with their size and with other parameters is examined.