Numerical models of pressure-driven fluid percolation in rock salt: nucleation and propagation of flow pathways under variable stress conditions

• DOI: 10.1007/s12665-022-10228-9
• Publication Date: 2022-02-17T06:02:47Z
• Authors: Keita Yoshioka; Amir Sattari; Mathias Nest; Ralf-Michael Günther; Frank Wuttke; Thomas Fischer; Thomas Nagel
• Keywords: Percolation (cognitive psychology); Percolation Theory

Abstract Success of our ongoing energy transition largely depends on subsurface exploitation. The can act as a “battery” to store dense fluids such hydrogen, or “host” sequester unwanted substances carbon dioxide radioactive waste. On the other hand, these operations cause pressure and/or temperature change and induce various (or cyclical) loadings surrounding formations. Their operational safety crucially hinges upon integrity. most imminent risk is nucleation cracks that lead loss mechanical Unlike hydraulic fracturing in geoenergy applications where one deliberately initiates at certain targets, we normally design system avoid fracturing. At designing stage, thus have no prior knowledge crack initiation locations propagation paths. And, computational tools should be able assess without knowledge. In this study, compared three approaches do not require prescribed geometries—the discrete element method, lattice variational phase-field approach—against percolation experiments rock salt. experimental results show different fracture paths depending boundary loads. geometries were reasonably matched by all despite some differences path irregularities. While approach predicts relatively regular paths, predicted methods are more irregular. These irregularities may seem comparable intergrain failure real rocks, but they also necessary triggers for methods. contrast, realization minimization system, grain level descriptions absent current formulation. findings highlight their predictive capabilities gaps bridged between continuum scales field-scale applications.