POLF: Two-dimensional finite-element model for predicting the areal flow of pollutant in confined and unconfined aquifers

A finite-element program for modeling two-dimensional (2D) pollutant transport in confined and unconfined aquifers is presented. The code accounts for the absorption and biological decay of the pollutant, which is supposed to behave as a tracer. The flow and pollutant transport equations are solved by using either a Galerkin finite-element (GFE) or a control;volume finite-element (CVFE) formulation. The discretization of the flow domain is obtained by using triangular finite elements and linear shape functions, whereas integration in time is performed by a finite-difference (FD) Picard scheme. For two problems of which the analytical solution is known, the results of the simulations carried out by the CVFE and by GFE formulations are compared, taking as evaluation parameters the global mass-balance errors and the average deviation between the numerical and analytical solutions. The listing of the FORTRAN 77 source code, along with the user manual and two input files for solving the above mentioned problems are available by anonymous FTP from IAMG.ORG. (C) 1998 Elsevier Science Ltd. All rights reserved