NUMERICAL-SIMULATION OF AN UNSATURATED FLOW EQUATION

A numerical model for an unsaturated flow problem by using the finite element method is established in order to simulate liquid moisture flo w in an unsaturated zone with homogeneous soil and deep subsurface wat er, and with different initial and boundary conditions. For infiltrati on or evaporation problems, a traditional method usually yields oscill atory non-physics profiles. However, nonoscillatory solutions are obta ined and non-physics solutions for these problems are evaded by using the mass-lumped finite element method. Moreover, the kind of boundary condition is handled very well.