Numerical Simulation in Reservoir Engineering:

An Overview

A. S. Harouaka and H. Menouar

CPM/Research Institute

King Fahd University of Petroleum & Minerals

Abstract

Reservoir simulation has been recently defined as the art, science and engineering of the modeling of flow in petroleum reservoirs by solving relevant equations using modern computers.

Specifically, we seek the solution to a system of highly nonlinear partial differential equations (PDE), describing a single or multiphase fluid flow in one two or three dimensions. The procedure most commonly used and accepted is to approximate the PDE by finite difference.

The discretisation process leads to a matrix A whose entries are mainly zeros. This matrix can be extremely large for reservoir engineering problems of a practical size. The solution technique needed to solve the matrix A is by far the most important part of any reservoir simulator and for large simulation problems, iterative solutions techniques have been preferred to direct ones.

The main objectives of this discussion are: 1) Present a brief description of a reservoir simulator; 2) show the different models currently being used and 3) describe how reservoir simulators are considered the primary tools for reservoir management.