Waterflooding Process in an Irregularly Shaped Oil Reservoir: A Finite-Volume Approach

Abstract

Oil reservoirs are porous and permeable rocks that allow the hydrocarbon accumulation. Reservoir simulations are necessary to obtain the best fluid flow conditions in the porous medium and increase oil recovery capacity. The aim of this paper was to study the influence of the absolute rock permeability on the oil recovery of a complex geometry oil reservoir, using water injection with the black oil model. Numerical simulations in boundary-fitted coordinates were performed in a two-dimensional and irregularly shaped reservoir. Finite volume method was used to solve the governing equations and two inverted five-spot meshes were set in parallel for a total injection time of 30 years. Results of injected porous volume per recovered oil volume, the water cut charts and the water saturations maps showed that the lower porous medium permeability increased the oil recovery, once the permeability intensified fingers and early breakthrough, which leads to high water production rates and consequent reduction of the waterflooding efficiency.