Mathematical Model For Soil-Column Experiment And Parameters Inversion

An important method for describing and researching solute transport in the soil and groundwater is by doing soil-column experiment. The target of the soil-column experiment is to study the geotechnical property, thickness and structure of the soil, determine the aquosity and the solute transportation parameters, and construct a transport model which satisfies the practical situation.Based on the solute transport theory, this paper is to study solute transport actions in the soils and groundwater in one dimension by analyszing two kings of soil-column experiments. The main study endeavors to do the following three things.Firstly, an improved optimal perturbation iteration algorithm was constructed by recommending a homotopy method. The improved inversion algorithm was testified to have wide convergent regions by performing on an inverse problem of determining parameters in multi-component solutes transport of sulphate.Second, a disturbed soil-column experiment was completed, and solutes transport model describing transfer behaviors of eight ions with nonlinear source (sink) terms relating with time was established based on the analysis of the experimental process. Furthermore, the improved optimal perturbation iteration algorithm was applied to determine unknown parameters in the model, and the numerical inversion results basically coincide with the breakthrough data.Finally, an undisturbed soil-column experiment was investigated, and a mathematic model which satisfies the practical situation was constructed by combining hydrodynamic dispersion theory with hydrochemistry analysis. Numerical simulation results show that the optimal perturbation iterative algorithm is effective at least to the inverse problem of multi-parameter identification arising in the undisturbed soil-column experiment.