Modeling Two Phase Flow in Large Scale Fractured Porous Media with an Extended Multiple Interacting Continua Method

摘要

We present a two phase flow conceptual model, the corresponding simulator (2pMINC) and a workflow for large-scale fractured reservoirs, based on a continuum fracture approach which uses the multiple interacting continua (MINC) method complemented with an improved upscaling technique. The complex transient behavior of the flow processes in fractured porous media is captured by sub-gridding the coarse blocks in nested volume elements which have effective properties calculated from the detailed representation of the fracture system. In this way, we keep a physically based approach, preserve the accuracy of the model, avoid the common use of empirically derived transfer functions and considerably reduce the complexity of the problem which is reflected in the speedup factors up to 1000. The results are verified by comparison to a discrete fracture model (DFM) for which the fractures and matrix are explicitly accounted for. The simulator is applied to an idealized medium with periodic fracture pattern and to a real, naturally fractured reservoir, mapped on the "wave platforms" along the Bristol Channel. The evaluation shows that the extended MINC model is able to reproduce both, the large-scale permeability and the dynamics of the fracture-matrix mass transfer, correctly.