Role of the process conditions on three-dimensional viscous fingering: Impact on enhanced oil recovery and geological storage

Abstract

The problem of viscous fingering is a scientific challenge in oil recovery and geological storage. The phenomena of viscous fingering in a three dimensional setting is widely different from the 2D analogue. Here, we study the three-dimensional viscous fingering morphology to investigate the effect of fluid miscibility and porous medium permeability. High resolution industrial grade X-ray micro-computer-tomography scanning is used to explore the 3D instability patterns. The phase miscibility of the injection fluid to the displaced fluid affects the fingering phenomena, transitioning from dispersion limited to diffusion. The areal sweep efficiency is higher for miscible case and is invariant with flow rates. We have used the fractal analysis to analyse the complex patterns, and the fractal dimension is related to the process conditions. We report 3D diffusion-limited aggregation simulations to obtain patterns similar to the miscible fingering patterns and provide insights on the pattern growth behaviour.