Combining finite volume and finite element methods to simulate fluid flow in geologic media

Abstract

The permeability, porosity, and fluid velocities that govern the flow of multi-phase fluids such as water, oil and steam in the earth's subsurface often vary over several orders of magnitude and the scales of interest vary from centimetres to kilometres. We describe a node-centred finite volume method coupled with a finite element method on an unstructured triangular grid to accurately and efficiently model multi-phase flow in geologic media. This is demonstrated by modelling multi-phase flows in complex geometries and with transport parameters that vary over several orders of magnitude.