Solute dispersion along and against the groundwater flow in two-dimensional finite aquifer

Abstract

The present work deals with numerical solution of advection-dispersion equation (ADE) to find solute distribution profiles along and against groundwater flow in two-dimensional finite homogeneous porous medium. Initially, the transport medium is supposed as non-solute free. A constant concentration is assigned throughout the medium at the initial time. An intermediate point is located in the medium from where dispersion of solute is studied along and against groundwater flow. Dirichlet boundary conditions are prescribed along co-ordinate axes from the intermediate point. Solute fluxes are prescribed as zeros at the extreme boundaries. For the numerical solution, alternating direction implicit (ADI) method is applied to approximate the ADE together with initial and boundary conditions. On approximation of the ADE by ADI method, a tridiagonal linear system of algebraic equations is obtained at each half level of time interval. This linear system of equations is solved graphically to illustrate solute transport.