Modeling of Two-Phase Flows

K. O. Lund
Engineering Consultant to SML Associates, Del Mar, CA, USA

Viscous equations are developed for regions with two interacting flowing fluids, or two fluid phases, such as occur in fluidized particle beds or the mixing of fluids. The descriptive equations are rendered into the standard COMSOL PDE matrix form, and solved over typical two-dimensional regions, as time-dependent interacting laminar flows.

The model geometry selected is that of a so-called spouted fluidized bed in which a two dimensional jet of gas is injected into a bed of particles. The resulting interface shear stress between the gas and the particles is modeled with a typical shear parameter, and viscous effects are included in the viscous terms with effective viscosities.

Results show the effect of the developing jet, the particle circulation, and the distribution of the void fraction.