Abstract: The mathematical model for radial transport of a solute is summed up in this paper. The action of non-equilibrium linear adsorption, the double property of porous media and the decay of solute are considered. With the first kind of boundary condition, one finds the analytical solution of these equations by Laplace transform and calculates the dimensionless solution by FORTRAN program with DJS-040. The distribution and change of solute are evaluated and the solution under various limit cases is given. By numerical analysis, one obtains some valuable conclusions.

Key words: rod with variable cross-section, axial extensibility, post-buckling, shooting method, numerical solution