Two Phase Equilibrium Distribution in Three- Dimensional P–

This work presents a methodology for determining the interface between wetting and nonwetting phases inside a three-dimensional porous space, at a given equilibrium state. The work is limited to the study of mechanical equilibrium. The method is based on a three dimensional extension of the opening method from image analysis presented in [1] and applied on threedimensional stochastically reconstructed porous microstructures of reservoir rocks. The great advantage of the presently proposed methodology with respect to percolation networks conception is that simplifying assumptions regarding the geometry of the porous space are avoided. In fact, invasion of wetting fluid in imbibition and wetting fluid retention in the later stages of drainage occur spatially through a complex structure of corners and intrinsic irregularities of pore surfaces that are very difficult to model using percolation networks of sites and bonds. Simulation results were compared with experimental data related to mercury intrusion and water-oil capillary curves were simulated for several distinct cases.