Two-Phase Modeling within Fractured Vuggy Reservoir

Abstract

The paper is devoted to the mathematical modeling of flows within discrete fracture network systems, taking into account the fluid flow along vugs associated with fracture intersections. A mathematical model is described for a two-phase flow accounting for the flow exchange between fractures and vugs, as well as capillary and gravitational forces. Capillary forces are characterized by the Young–Laplace model which takes into account rock wettability, surface tension, fracture aperture, and vug cross-section diameters. The appropriate numerical simulation techniques are presented. Under various wettability conditions, the effect the flow within vugs has on the water–oil displacement process in a fractured vuggy reservoir is numerically investigated. It is shown that the presence of vugs at the intersections of fractures may significantly influence the flow characteristics under certain conditions.