Nonmonotonic traveling wave solutions of infiltration into porous media

Published

Journal Article

In uniform soils that are susceptible to unstable preferential flow, the water saturation may exhibit a nonmonotonic profile upon continuous infiltration. As this nonmonotonicity (also known as saturation overshoot) cannot be described by the conventional Richards equation, there have been proposed possible extensions to the unsaturated flow equations, including a nonmonotonic capillary pressure-saturation curve and a second-order hyperbolic term. Here, we present analytic traveling wave solutions to the extended Richards equation. These new solutions indeed display a nonmonotonic saturation profile, similar to previous simulation results. We show that these extensions need a regularization term to produce a unique solution. We develop complete analytic solutions using a relaxation regularization term, and we discuss the results in terms of recent measurements of saturation overshoot. Copyright 2008 by the American Geophysical Union.

Full Text

Duke Authors

Cited Authors

  • DiCarlo, DA; Juanes, R; LaForce, T; Witelski, TP

Published Date

  • February 1, 2008

Published In

Volume / Issue

  • 44 / 2

International Standard Serial Number (ISSN)

  • 0043-1397

Digital Object Identifier (DOI)

  • 10.1029/2007WR005975

Citation Source

  • Scopus