Internal friction angle model of particles

Abstract

Currently, pressure from industry to streamline processes by creating their simulation models, and thus to gradual digitization is increasing. The essence of representative simulation models of bulk materials is to understand the principles and laws of the real behavior of particles. The aim of this study is therefore to find and quantify the possibilities and principles of how particles can change their position relative to other particles. The possibilities of particle displacements were expressed using their specific trajectories and work ratios, or internal friction angle values. This created a new comprehensive model of the internal friction angle of particles independent of particle size. It enables the interpretation of the determined values of the angles of internal friction of particles and its application in the field of simulations of mass and process models. The model can be used to determine the basic composition of particles in volume and the dominant ways of their mutual displacements.

Figure 1

Diagram of the work of particles during displacement.

Figure 2

Particle displacement. (a) Initial position of the rotary test, (b) final position of the rotary test, (c) schematic representation of the initial position, (d) schematic representation of the displacement.

Figure 3

Possibility of symmetrical values of displacements ǀǀΔxǀǀ and ǀǀΔzǀǀ.

Figure 4

Initial and terminal positions of the displacements T₁₁–T₁₅ and T₂₁–T₂₅.

Figure 5

View of the grains of the measured salt samples, (a) edible iodized salt, (b) pure natural salt, (c) fine sea salt, (d) coarse-grained sea salt, (e) Sicilian fine salt, (f) dehydrated sea salt, (g) fine coastal sea salt, (h) Sicilian coarse-grained salt, (i) edible stone salt, (j) Italian coarse-grained sea salt.

Figure 6

Gaussian distribution φsf for individual samples, for the whole set of samples φsfC and mean probable angle of internal friction of particles φC.