Author(s)

F. De Smedt & M.A. Sbai

Abstract

Groundwater pollutant transport modelling based on the finite element technique with M-matrix preconditioning F. De Smedt & M.A. Sbai Laboratory of Hydrology, Free University of Brussels, Pleinlaan 2, 5-70JO, anwWj, ae/g/wm E-mail: masbai@vub.ac.be Abstract Transport of pollutants in groundwater is simulated by means of a 3D finite element model. The obtained system of numerical equations is very large, sparse, non-symmetric and usually difficult to solve with standard iterative techniques. It is proposed to improve the convergence behavior of the solvers by preconditioning, where the existence of the preconditioning is guaranteed by using an M-matrix type of transformation. The usefulness of the method is demonstrated by solving several test examples, using different solvers as the minimal residual method and the stabilized biconjugate gradient method and different preconditioning schemes as diagonal scaling and incomplete factorization. It is shown that M-matrix

Keywords