Simulating advective-dispersive transport in groundwater: an accurate finite difference model

Finite difference models (FDMs) may provide oscillatory results when employ ed to predict contaminant transport in groundwater. The oscillation is usua lly avoided by adapting upwind methods. The upwind methods are reported to introduce large artificial dispersion. An improved FDM has been developed t o provide oscillation free results with the introduction of minimum artific ial dispersion. The improvement has been achieved by developing an expressi on of the minimum artificial dispersion needed to provide accurate results. The improved FDM provides results in excellent agreement with the analytic al solution. Further, the improved FDM can easily be extended to two- or th ree-dimensional problems. (C) 1999 Elsevier Science Inc. All rights reserve d.