Laplace Transform Finite Element Method (LTFEM) for the Analysis of ContaminantTransport in Porous Media

摘要

This paper develops a finite element method for the analysis of contaminanttransport in porous media. The Laplace transform removes the time derivative and consequently the transformed equation contains only spatial derivatives. The transform equation is then approximated using the finite element method and solved to give the values of nodal variables in Laplace transform space. The actual solution in the time domain is found by numerical inversion of the Laplace transform. The actual solution in the time domain is found by numerical inversion of the Laplace transform. In this paper, the disadvantages of using complex arithmetic in the analysis of solute transport are overcome by using a numerical Laplace transform inversion technique due to Stehfest (1970) which uses only real arithmetic and thus provides a significant reduction in storage together with an increased efficiency of computation.