Direct numerical approach for determination of H2-water flow functions applicable to underground hydrogen storage and production

• Published in: Journal of energy storage 2024-08, Vol.96, p.112573, Article 112573
• Main Authors: Bagheri, Matin, Mahani, Hassan, Ayatollahi, Shahab, Zivar, Davood
• Format: Article
• Language: English
• Subjects: Capillary pressure; Direct numerical simulation; Heterogeneity; History matching; Hydrogen relative permeability; OpenFOAM; Underground hydrogen storage and production
• ISSN: 2352-152X
• DOI: 10.1016/j.est.2024.112573

Abnormally low hydrogen endpoint and crossover point in the relative permeability-saturation functions for hydrogen-brine have been reported in the published literature. This paper develops a direct computational fluid dynamics simulation approach to understand the two-phase flow of hydrogen and water at the pore-scale during primary drainage and imbibition, as relevant to underground hydrogen storage (UHS). History matching of displacement data via genetic algorithm optimization was performed to simultaneously compute capillary pressure and relative permeability functions for four pore-scale geometries, examining the impact of pore-scale heterogeneity (e.g., tortuosity, coordination number, and pore geometry) on the flow characteristics. The findings reveal that in the drainage stage, increased heterogeneity lessens viscous fingering, leading to a lower remaining water saturation, and a lower relative permeability for both hydrogen and water phases. These results can explain the low hydrogen endpoint (even