Modelling of processes in fractured rock using FEM/FVM on multidimensional domains

摘要

The paper deals with a new approach to the numerical modelling of groundwater flow in compact rock massifs.Empirical knowledge of hydrogeologists is summarized first. There are three types of objects important for the groundwater flow in such massifs—small fractures, which can be replaced by blocks of porous media, large deterministic fractures and lines of intersection of the large fractures. We solve problem of the linear Darcy's flow on each of these three separated domains and then we join them by coupling the equations. We do not require geometrical correspondence between 1D, 2D and 3D meshes, which simplifies the process of the spatial dicretization. The mixed-hybrid FEM with the lowest-order Raviart–Thomas elements is used for approximation of the solution. The advective mass transfer is solved by the FVM on the same discretization as the flow problem.Results of numerical experiments with the model are shown in the end of the paper.