DPM

Modeling multiphase flows often requires the consideration of particulate matter - especially in industrial applications. The Discrete Phase Model (DPM) is a convenient tool for calculating the trajectory of particles (but also of liquid droplets) with a relatively small fraction in the volume of a fluid. The animation below shows the trajectories of solid particles <5 μm in the cyclone. These trajectories are chaotic, filling practically the entire available volume inside the de-duster. As you look closely, some of the particles are entrained by the gas and leave the cyclone through the central exit.

Much heavier particles, with the same density but about 100 μm in diameter, behave completely differently - their trajectories are ordered, creating a characteristic spiral near the walls of the dust collector. In the lower (conical) part, you can see how the wall angle affects the falling speed of the particles.