CALCULATION OF LARGE-SCALE PROPERTIES FOR MULTIPHASE FLOW IN RANDOM POROUS MEDIA

A numerical procedure for the calculation of large-scale properties for two-phase flow in heterogeneous porous media using the Large-Scale Averaging technique is presented. Validity tests for simple idealistic geological models such as stratified media are presented. Special emphasis is put upon the importance of the anisotropic nature of relative permeabilities using illustrations based on Boolean media. As a more realistic model of geological structures, two-dimensional porous media with random spatially correlated permeability distributions have been generated using different methods. Other multiphase properties are chosen to depend on the permeability. The equivalent or effective properties are calculated using the Large-Scale Averaging Method. The influence of the size of the averaging surface for a given correlation length as a function of the variance of the permeability is studied. Some general rules for the calculation of the large-scale properties of random porous media have been established.