28. Computational Model for Path Mapping of Spherical Particles in a Continuous Medium Applied to Iron Ore Transfer Chute

During the fall of bulk materials, the air around the material mainstream is dragged by the non-slip condition modifying the near pressure and velocity fields generating air currents around the bulk material fall. A particle that comes off the mainstream will be subject to the drag force due to the moving air and can be transported away, characterizing the formation and dispersion of dust. This work applies a computational model in an iron ore conveyor belt transfer chute to evaluate the forces acting on microparticles that can be carried away from the control volume. The computational model is easy to implement, has low computational effort, and allows to map the particle’s path making it possible to estimate the particle diameters with a greater propensity for dust formation than observing the preferred dust escape paths. The capacity of an extractor fan to absorb suspended particles was also evaluated. Analytical solutions for the particle velocity in continuous medium considering the Stokes flow are presented and used in model validation. Physical parameters relevant to flows involving particle displacement (specifically iron ore particles) are presented and discussed: terminal velocity, terminal time, relative Reynolds number, drag coefficient, and suspension time.