1. MECHANICAL INTERACTION OF PARTICLES

In the previous chapter, interesting relationships were obtained for the examined process. However, they are relatively abstract and require detailed verification. Therefore, it will be attempted to approach this process from a slightly different side. Attention will be given to the mass movement of particles in their physical realisation taking into account the presence of mechanical contact interaction of solid particles in a two-phase flow.

Taking into account the mechanical interaction of particles in a flow greatly complicates the considerations regarding the mechanism of gravitational separation.

This interaction results in a constant redistribution of the velocities of different size classes as a result of inhibition of fine particles and acceleration of larger particles in the direction of movement of the medium, leads to changes in the trajectory of movement of the individual particles, increases the radial component of their velocity generated by different migration effects. Identical results may be obtained not only by direct contact interaction of particles but also by affecting them through a moving medium, especially if they are closely spaced.

Under the same regime parameters, the frequency of such an interaction depends greatly on the physical properties of the material, primarily on the particle size. It is evident that the number of interactions amongst particles of different sizes increases with increasing concentration of the material in the flow, but it is not clear what is the dynamics of this increase. There are three aspects of the model examined here.

First, only the...