Two-dimensional unsaturated flow in irregularly shaped regions using a finite volume method

Abstract

To describe the two-dimensional flow of water in unsaturated soil, the governing equation is solved on a mesh constructed from small area elements. A transformation is introduced with which these possibly distorted rectangular elements of the physical plane are mapped into computational squares. Thus, irregularly shaped regions, which present difficulties when attempting to describe their geometry on an orthogonal computational mesh, can be more easily modelled. Using this methodology, here called the finite volume method, numerical results are obtained showing the ability of the method to describe transient unsaturated flow.