Study of Fractures in a Permeable Rock Matrix using Two Phase Numerical Flow Model–Effect on Relative Permeability Curve

The presence of open fractures in a permeable matrix generates highly heterogeneous permeability fields which have a large impact on the relative flow of oil and water. This results in highly variable velocities which generates complex oil-water fronts and strongly heterogeneous water saturation fields. Such conditions makes prediction of reservoir behaviour difficult and efficient recovery problematic. One of the best known effects is early water breakthrough at wells due to the preferential flow of water along a connected fracture system. In the present paper the effects of open fractures on the flow of oil and water are investigated using a two phase numerical flow model with some simple and simulated and natural fractures patterns. The results are used to investigate the nature of ‘pseudo curves’ (relative permeability curves for volumes of heterogeneous rock) in the case of fractured permeable rocks. And we will get a important result that increasing fracture aperture beyond a critical value does not significantly alter the pseudo relative permeability curves resulting in flow channeling and thus affects production.