MODEL OF MOTION AND SEDIMENTATION OF A CHARGED GAS SUSPENSION IN AN ELECTRIC FIELD

We have constructed a model of the dynamics of a charged gas suspension moving in an electric field under the action of interphase friction and Coulomb forces and used it to describe the process of powder coloration. The model incorporates the equations of motion of the carrier and dispersed phases obtained with account for the interphase momentum and energy exchange. The carrier medium is described by a system of Reynolds-averaged Navier-Stokes equations for a compressible heat-conducting gas with a Spalart-Allmaras model. The dispersed phase is given by the mass equation with account for the turbulent diffusion and by the conservation equations of momentum components with account for the action of the Coulomb force and aerodynamic friction, as well as by the internal energy equation. The system is written in generalized coordinates in dimensionless form and is solved by the explicit McCormack method with splitting into spatial directions and by the nonlinear correction scheme. The model is used to investigate the velocity and density fields of the gas suspension in the interelectrode space near the surface on which the powder is deposited.