Boundary Element Formulation For Flow In Unsaturated Porous Media.

Abstract

A numerical single-phase model for unsteady state unsaturated flow has been derived and
solved using the boundary element method (BEM). BEM procedures have had a relatively restricted
development due to the limitation of the conventional BEM to deal with the highly non-linear
governing equations. Here, the governing equation has been represented as a non-homogeneous
Laplace equation, and the non-homogeneous part has been dealt with by using the dual reciprocity
method (DRM). The soil-water characteristic curve according to a van Genuchten approach was
employed. The developed scheme was implemented in a 3D code and applied to solution of upward
and downward infiltration in clay showing good agreement with numerical solutions previously
reported in open literature.