In this study, we introduce an open-source benchmark gallery for a systematic verification of numerical simulations of coupled multi-field processes in geological storage and sequestration. Here, the focus lies on assessing the integrity of a host rock and/or geological barrier, which requires understanding material failure and behavior under different thermal-hydraulic-mechanical-chemical (THMC) conditions. To support quality assurance of the simulation workflows, the gallery provides automated benchmarking and peer-reviewed code development.
Since closed-form solutions covering all aspects of non-isothermal two-phase flow in deformable media (TH2M) problems are not available, the verification procedure is subdivided into simpler conceptual models, up to single-variable processes (Grunwald et al., 2022). These reduced complexity problems can be described by semi- or fully analytical solutions. Extensive verification of very basic combinations (T/H/M/HM/TH etc.) was already conducted, therefore, focus lies on the investigation of more complex problems.
In the context of TH2M systems, the gallery includes three cases relevant to CCS:
THM problem: Thermally induced expansion of liquid and solid phases resulting in thermal strain in the surrounding solid matrix and fluid displacement. (Booker and Savvidou, 1985; Chaudhry et al., 2019)
TH2 problem: Phase change and heat transport in a thermal gradient (Udell and Fitch, 1985; Helmig et al. 1997)
TH2M: Heat loss to under- and overburden due to non-isothermal, supercritical CO2 injection into reservoir. (LaForce et al. 2014a and 2014b; Green at al. 2021)
The gallery consists of comprehensive browser-integrated problem descriptions, analytical solutions, and numerical simulations obtained with the open-source simulation tool OpenGeoSys (Bilke et al., 2022).