Building a Robust Numerical Model for Mass Transport Through Complex Porous Media

J. Perko[1], D. Mallants[1], E. Vermariën[2], and W. Cool[2]
[1]Belgian Nuclear Research Centre (SCK-CEN), Mol, Belgium
[2]Belgian Agency for Radioactive Waste and Enriched Fissile Material (ONDRAF/NIRAS), Mol, Belgium

Mass transport modelling through porous media is typically characterized by complex physics and geometry. In the particular case of radionuclide transport, modelling for radioactive waste repositories, an additional level of complexity, and thus uncertainty, originates from the long time frames involved. Performing a safety analysis of a radioactive waste disposal system requires therefore reasonable simplifications which enable us to model such complex system thereby minimizing the effect of uncertainties.

In this work several examples, calculated by COMSOL Multiphysics, are selected to show the acceptable level of simplification to assure representative yet robust modelling of radionuclide transport from a disposal facility.