Two phase partially miscible flow and transport modeling in porous media: application to gas migration in a nuclear waste repository

TL;DR

This paper develops a two-phase flow model for simulating hydrogen migration in deep geological repositories, incorporating capillary effects and high gas diffusivity, and demonstrates its effectiveness through computational tests.

Contribution

It introduces a novel compositional model using specific variables for accurate simulation of gas generation and migration in nuclear waste repositories.

Findings

Model effectively simulates hydrogen migration in repositories.

Inclusion of capillary effects improves simulation accuracy.

Model handles gas appearance and disappearance consistently.

Abstract

We derive a compositional compressible two-phase, liquid and gas, flow model for numerical simulations of hydrogen migration in deep geological repository for radioactive waste. This model includes capillary effects and the gas high diffusivity. Moreover, it is written in variables (total hydrogen mass density and liquid pressure) chosen in order to be consistent with gas appearance or disappearance. We discuss the well possedness of this model and give some computational evidences of its adequacy to simulate gas generation in a water saturated repository.