Chapwanya, MichaelStockie, John M.2011-02-242011-02-242010Chapwanya, M & Stockie JM 2010, 'Numerical simulations of gravity-driven fingering in unsaturated porous media using a nonequilibrium model', Water Resources Research, vol. 46, W09534, pp. 1-16. [http://www.agu.org/journals/wr/]0043-139710.1029/2009WR008583http://hdl.handle.net/2263/15935This 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. (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.en© 2010 by the American Geophysical Union.Experimental resultsGravity-driven fingeringSaturationPorous materialsPostprint Article