Numerical Modelization of the Pollutant’s Insertion in a Soil of South Morocco

Abstract

Nowadays, one of the most studied issues is pollution; because of the repercussion on human health, many researchers have focused their searches on understanding such phenomena. In order to do so, searchers have needed to understand the penetration of the pollutants in the soil depending of the nature of this last one. In this work, the focus is on the flow of pollutants in a porous, unsaturated and fractured soil. The flow of fluids in such media is characterized by the Richards equation. In order to have a solvable problem, some basic equations are needed in order to establish the relationship between fluid pressure and relative permeability. Then, the pollutant transport equation, and the equation of thermal transfer will be added to the obtained system. Because of the strong non-linearity of the equations, the discrete method has been adopted to discretize this system of equations. For the resolution, the ADI (Alternating Direction Implicit) method is used. Then, a solver has been developed to solve such equations. The figures drawn in this paper have helped understanding the criticality of three main parameters: temperature, velocity and concentration. The following conclusion has been reached: the temperature decreases over time, which is explained by the amortization of the heat transfer from the soil surface over time. The velocity decreases in an exponential way. This decrease is justified by the action of friction of the fluid with the media. The concentration of the pollutants increases over time, which is explained by the accumulation of products of dissolution of pollutants. The originality of this work is the development of a numerical solution to solve the flow of the pollutants for such media. Then, it has been applied on a specific region of South Morocco. Copyright © 2020 Praise Worthy Prize - All rights reserved.