The Paris agreement, adopted by 196 parties in 2015, aims at limiting global warming to below 2° compared to pre-industrial levels. To achieve this goal, the reduction of greenhouse gas emissions in the atmosphere is crucial and requires the transition towards renewable energies and effective energy storage facilities. Additionally, a safe long term sequestration of CO2 is considered a promising strategy to reduce emissions into the atmosphere. The aforementioned technologies entail a massive use of the subsurface for fluids injection, storage and production. Understanding subsurface geological processes is crucial to guarantee the mechanical integrity and avoid environmental damage, such as fracturing and induced seismicity, and to develop renewable alternatives for energy generation. The key for the successful assessment of subsurface activities is the ability to perform accurate numerical simulations able to predict the effects of soil exploitation.
The PDGeoFF project focus on the design and analysis of advanced nonconforming polyhedral discretisation methods for geomechanical modelling. The versatility of polyhedral finite element methods allows to successfully tame the main numerical challenges that have to be accounted for in computational geosciences: the geometric complexity arising from the presence of various layers and fractures, the strong coupling between the flow and the mechanics, and the possible rough variations of the physical parameters. The project tackles the design and the analysis of advanced numerical methods for simulating coupled fluid flow and deformation in fractured poroelastic media. The main goal is to provide an efficient tool to evaluate and prevent risks related to several human geological activities including, in particular, geothermal power production and CO2 sequestration and storage.
During the project, we were able to develop new nonconforming polyhedral finite element methods for fully coupled problems in poromechanics taking into account the hydraulic and thermal effects on the deformation of the porous media as well as the presence of fractures and inner interface between regions with different physical properties.