Numerical modeling of contamination transport equation in porous media for transient flow regime by finite volume method

Groundwater is an essential source of fresh water, which is less prone to pollution in comparison to surface water, and access to this valuable resource is affordable. These issues make groundwater a viable source during surface water shortages such as drought, especially in arid and semi-arid countries. In this research, the equation of contamination transport in groundwater is modeled by a novel dual discrete finite volume method (DDFVM). Using this numerical method, the contamination concentrations are obtained at the center and vertices of each element. This model has been applied to an unstructured triangular mesh that could be fitted to complex geometric boundaries. For the transient flow regimes, the flow equation has been coupled with the contaminant transport problem, and the results of the numerical model are validated with the model of Modflow. Finally, the flow and transport FV coupled model has been applied in a porous media with strong heterogeneity. The free-oscillation results for the two parameters of head and concentration demonstrate the stability of the model.