A hybrid method for the simulation of radionuclide contaminant plumes in heterogeneous unsaturated formations

The numerical simulation of multiphase flow and contaminant transport problems that take place around nuclear waste repositories is an important tool for selecting appropriate sites for these facilities. The goal of this paper is to present an accurate and efficient simulation tool to approximate flows in heterogenous unsaturated hydrogeological environments. We employ a hybrid method that combines a Eulerian finite volume approximation scheme for the underlying water–air flow problem with a locally conservative Lagrangian particle tracking method to approximate the transport of a radionuclide within the water phase. The Lagrangian scheme is computationally efficient and theoretically free of numerical diffusion. Numerical simulations showing the effectiveness of the new procedure are presented and discussed.

► We model multiphase flow and contaminant transport.
► We present an accurate and efficient simulation tool.
► We combine a Eulerian scheme and a Lagrangian particle tracking method.
► Numerical simulations showing the effectiveness of the new procedure.