Research of capillary forces influence on liquid flow in fractures within non-uniform aperture

The paper presents a mathematical model of a two-phase flow in a discrete fracture network, accounting for non-uniform fracture aperture, flow exchange between fractures, capillary and gravitational forces. Capillary forces are described by Young-Laplace model, which takes into account rock wettability and surface tension. The influence of the channel structure in a fracture, capillary and gravity forces, pressure gradient, the ratio of water and oil viscosities on flow dynamics and the oil recovery factor is explored. Capillary forces and the structure of channels in a fracture are proved to play a decisive role in oil displacement process.