EFFECTS OF NON-NEWTONIAN FLUID AND POROUS-MEDIUM PARAMETERS ON 2-PHASE FLOW IN POROUS-MEDIA

This paper describes a three-dimensional finite element method for mod elling two-phase non-Newtonian flows using the power law to describe t he non-Newtonian behaviour of the non-wetting and/or the wetting fluid . The fluids can be either dilatant or a pseudoplastic. The technique allows the two-phase flow behaviour to be studied using described empi rical parameters for the fluid/fluid interaction. The porous medium ma y be anisotropic (i.e. it may be described by a variable permeability tensor), and the permeability may be a function of distance in any of the three orthogonal directions. The porosity of the medium may also b e defined as a function of the spacial coordinate system. The first ap plication illustrated here is the one-dimensional displacement of a no n-wetting fluid by a wetting fluid in a isotropic porous medium. The r esults illustrate the wetting fluid saturation profile moving through a porous medium, and the effects on the velocity and shape of the prof ile when changing non-Newtonian and two-phase flow parameters, which g ives insights into the choice of drilling fluids. The effects of spati ally varying permeability is also investigated and presented here.