Evaluation and selection of numerical simulation methods for shale gas reservoirs

Abstract

The complex fracture network brings great challenge to the numerical simulation of shale gas reservoirs. Based on the discrete fracture model (DFM), micro scale model and field scale model are established to investigate the influence of fracture types on the reservoir performance when the correspondence of matrix permeability and fracture aperture is different. Results show that: because the magnitude of shale gas reservoir matrix permeability is (10−8–10−4)×10−3μm2 and the SRV is a prerequisite for shale gas production, hydraulic fractures play an important role in the shale gas production while the contribution of natural fractures in and out the SRV is relatively small. Therefore, considering the computational complexity and precision, natural fractures can be characterized by matrix-natural fracture apparent permeability model and continuum model while the hydraulic fracture can be characterized by the discrete fracture network (DFN) with less computational grids and high efficient.