Numerical Simulations of Gravity-Driven Fingering in Unsaturated Porous Media Using a Non-Equilibrium Model

Abstract

This is a computational study of gravity-driven fingering instabilities in unsaturated porous media. The governing equations and corresponding numerical scheme are based on the work of Nieber et al. [Ch. 23 in Soil Water Repellency, eds. C. J. Ritsema and L. W. Dekker, Elsevier, 2003] in which non-monotonic saturation profiles are obtained by supplementing the Richards equation with a non-equilibrium capillary pressure-saturation relationship, as well as including hysteretic effects. The first part of the study takes an extensive look at the sensitivity of the finger solutions to certain key parameters in the model such as capillary shape parameter, initial saturation, and capillary relaxation coefficient. The second part is a comparison to published experimental results that demonstrates the ability of the model to capture realistic fingering behaviour.

References in corpus (1)

• Dynamics of Wetting Fronts in Porous Media

Cited by in corpus (3)

• A numerical study of two-phase flow with dynamic capillary pressure using an adaptive moving mesh method
• A moving mesh finite difference method for non-monotone solutions of non-equilibrium equations in porous media
• A numerical study of two-phase flow models with dynamic capillary pressure and hysteresis