Efficient Finite-Difference Model for Flow in a Reservoir With Multiple Length-Scale Fractures

Abstract

Summary In this paper we describe a hierarchical approach for modeling fluid flow in a naturally fractured reservoir with multiple length-scale fractures. Based on fracture length relative to the finite-difference grid size, fractures are classified as short disconnected fractures, medium-length fractures, and long fractures. Effective grid-block permeabilities, associated with the short-and medium-length fractures, are used as input to a finite-difference simulator. We also present a separate transport equation for flow through long fractures to capture effects of large-scale high permeability pathways. Simulation results from the new hierarchical approach are compared with those from the conventional dual porosity/permeability model.