CIEMAT
The analytical solutions for solute diffusion equation in porous media are very useful for analysing diffusion tests carried out in the laboratory and to solve real problems for simple geometries and/or homogeneous materials. They are also widely used to validate results obtained from numerical modelling.
Analytical solutions can be implemented relatively easily in spreadsheets or can be written in programs such as MathCad and MATLAB, which makes them especially useful as a tool to understand the effects that natural, physical and chemical processes have on the spread of contaminants in groundwater and porewater.
This document presents a wide variety of analytical solutions to describe diffusion of solutes in 1D, but that can be easily generalized to 2D and 3D, with different initial and boundary conditions. Special emphasis will be given to the experimental methods used in a laboratory for determining diffusion coefficients.