Simulation of Water Coning in Oil Reservoirs Using a Corrected IMPES Method

Implicit pressure-explicit saturation method (IMPES) is widely used in oil reservoir simulation to study the multiphase flow in porous media. This method has no complexity compared to the fully implicit method, although both of them are based on the finite difference technique. Water coning is one the most important phenomenon that affects the oil production from oil reservoirs having a water drive source. Since the water coning affects final oil recovery, identification of this phenomenon is very important. In order to study this phenomenon, one should determine the critical production rate, the breakthrough time and watercut percentage. The scale of the problem hinders the numerical simulations, IMPES included, for a long running time. A corrected IMPES method is used here to overcome the long running time problem by choosing larger the time step for the coning problem. A water-oil phase flow system in the cylindrical coordinate that is commonly used to simulate water coning phenomenon is solved by the corrected IMPES method. The validity of the model is checked against Aziz and Settari’s model, which is based on a complicated fully implicit method.  The effects of the production rate and the thickness of the oil zone on the breakthrough time have been investigated. The results were found to be in good agreement with the results of previous studies.