FLOW OF SUSPENSIONS IN TWO-DIMENSIONAL POROUS MEDIA WITH MOBILE AND IMMOBILE LIQUID ZONES

In this paper, flow of suspensions in a 2D porous medium is considered. The porous medium consist of two zones, one of them is saturated with a mobile, pure (without any solid particles) liquid and another one is saturated with an immobile liquid. The flow of suspensions occurs with colmatation and suffosion, longitudinal and across diffusion effects and in the immobile liquid zone only, diffusion transport of particles is observed. The problem is numerically solved and the influence of colmatation-suffosion, diffusion, hydrodynamic dispersion effects on filtration and mass transport characteristics is estimated. The fields of relative concentration of particles in both mobile and immobile liquid zones, porosity, permeability, and pressure gradient in the mobile liquid zone are determined for several values of diffusion, dispersion coefficients, and colmatation-suffosion intensity coefficients. Relative current, common, and total mass fluxes of solid particles through the common boundary of the mobile and immobile liquid zones are also determined. It is shown that the presence of immobile liquid zones in porous media considerably alter both the filtration and transport characteristics. Colmatation and suffosion effects in the zone with mobile liquid influence not only the filtration and transport characteristics of this zone, but also the diffiision particle transport from the zone with the mobile liquid into the zone with the immobile liquid. Results can be important in field data interpretation during water flooding in oil reservoirs, wastewater filtration, environment protection, etc.