Experimental and numerical study of the impact of viscosity ratio and velocity on the multiphase flow in micromodels

Abstract

The process of fluid displacement in a microscale of porous media in oil reservoirs rock is affected by several factors. Understanding the effects of factors in multiphase flow mechanisms in porous media through numerical investigations allows us to estimate the flow behavior. In this study, the effect of important parameters like viscosity ratio and velocity on displacement in porous media was investigated using the volume of fluid method as a numerical model. So, a set of governing equations were calculated under a wide range of injection velocities and viscosity ratios to characterize displacing pattern. A similar experiment was done on a micromodel to validate the numerical method, and a rational agreement was reached between the experimental and numerical results. Saturation, velocity, pressure, breakthrough times, displacement efficiencies and displacement patterns were studied. Results show that the effect of viscosity ratio is more important than the effect of velocity. If the viscosity ratio increases five times, injection rate has to decrease 10 times to recover the same amount of oil. However, in a homogeneous porous media, fingering takes place due to the interaction of some forces where in a heavy oil reservoir the viscous forces play the main role. Also, pore scale events were investigated to better understanding the role of film rupture, coalescence, pinch off and splitting in meniscus displacement through the throat of the pore.