Pneumatic Separation of Fractions of a Polydisperse Gas Suspension in a Low-Velocity Flow

The authors have described a change in the spatial dispersity distribution of a powder gas suspension on a z-shaped classifier of particles. The process of separation of particles by size occurs under the gravity force and the aerodynamic resistance force and is described by the Eulerian model of a polydisperse gas suspension consisting of several fractions of particles of varying radius and of air as the carrier medium. The dynamics of dispersed fractions is described by systems of equations of the gasdynamic type with account of the interphase exchange of momentum and energy with the carrier medium whose motion is described by a system of Navier–Stokes equations which takes account of the exchange of momentum and energy with the dispersed fractions. The system of equations of a polydisperse gas suspension is represented in generalized curvilinear coordinates and is solved by the explicit predictor–corrector method with splitting of the spatial operator by directions and with the scheme of nonlinear correction at each time step. Consideration has been given to the time and space characteristics of the process of motion of the carrier medium and the dispersed fractions.