Network Modeling of Drainage and Imbibition in Microfractured Porous Media

摘要

This paper investigates two-phase flow in microfractured porous media. We obtain relative permeabilities and capillary pressure curves for drainage and imbibition processes using a two-dimensional microfracture network model. The system of microfractures is composed of interconnected parallel plates of varying apertures, lengths and pre-established orientation. Fluid flow in each microfracture unit is described by the paralle plate flow model. Capillary pressure for individual microfractures is obtained as a function of fracture aperture. The model takes into account capillary and viscous forces, thus the model allows for the analysis of different configurations of fluids on the network obtained with different capillary numbers and viscosity ratio. Relative permeabilities and capillary pressures are obtained as a function of the average saturation of the fluids in the network and the effect of different flow conditions on these curves is presented.