Numerical Analysis of Viscous Fingering Instability due to Miscible Displacement
A. Nemati, H. Saffari, B. Z. Vamerzani, R. Azizi, S. M. Hosseinalipoor, H. Miri
Iran University of Science and Technology, Tehran, Iran
Keywords: неустойчивость вязкостного пальцеобразования, закон Дарси для двухфазной жидкости, пористая среда, поток смешивающихся жидкостей, viscous fingering instability, two-phase Darcy's law, porous media, miscible flow displacement
Abstract
In this study, miscible viscous fingering instability is examined numerically by using the two-phase Darcy's law and transport equations. The effects of the viscosity ratio, anisotropic permeability, and porosity on instabilities are investigated. The finger patterns and their splitting and spreading in the domain are discussed. An image processing algorithm is applied to concentration contours to quantify instability parameters, such as the breakthrough time, efficiency, and fractal dimension. It is revealed that more complex fingers are obtained as the viscosity ratio increases, while the efficiency and the breakthrough time decrease. It is demonstrated that high permeability perpendicular to the flow direction leads to instability intensification and to an increase in the fractal dimension, whereas changing the porosity does not have any considerable impact on viscous fingering instability.
|
