Computational study of fingering phenomenon in heavy oil reservoir with water drive

Abstract

The objective of this paper is to numerically study the flow in heavy oil reservoir with water drive. The main focus is to investigate the viscous fingering phenomenon and how it affects the oil recovery. Two-dimensional simulations of oil production in a homogeneous heavy oil reservoir were carried out using ANSYS Fluent as the Computational Fluid Dynamics software. Cross section of the reservoir is simulated to study the fingering behaviour; an instability which occurs in the water oil contact (WOC) zone. Fingering occurs in a homogeneous porous media due to the interaction of several forces where the viscous forces play the dominant role in a heavy oil reservoir. Velocity and pressure profiles, breakthrough times and flow rates were studied. Furthermore, the critical velocity is calculated to indicate the instable flow region. The low velocity of the water oil interface is sufficient to create the instabilities of the water front. The ANSYS VOF model is verified against experimental data for viscous fingering found in literature. Reasonable agreement between the experimental and simulated results was obtained. Simulations were performed to check the grid size and time step size dependency.