Multiphyisics geomechanical simulations using REDBACK
This project aims at understanding the geomechanical behaviour of rocks at high temperature and pressure by considering multi-scale and multi-physics processes. It investigates a new constitutive model which needs to be calibrated against available laboratory experiments. It also accounts for chemical dissolution and precipitation of rocks at the micro-scale and studies their influence on the hydraulic conductivity (permeability) at the larger scale, which plays a major role in geological events like fault reactivation.
Area of science
Geosciences
Systems used
Magnus, Zeus
Applications used
MOOSEThe Challenge
Most physical models to simulate the mechanical behaviour of rocks under deformation are derived from an engineering perspective and require preliminary laboratory experiments to be calibrated. This approach makes it hard to extrapolate the behaviour beyond laboratory conditions and simulate scenarios at great depths, involving high temperatures and pressures.
The Solution
This project aims at developing a physics-based approach to palliate those deficiencies and increase the prediction power of numerical simulations under untested conditions. A new constitutive model is investigated that accounts for temperature and pore pressure explicitly to simulate mechanical deformations. A multi-scale approach also allows to account for the impact of the microstructure – and its evolution due to chemical reactions- on fluid flow at the larger scale.
The Outcome
The physical models were coded in the REDBACK module of MOOSE, a platform specifically designed to run on supercomputers. The calibration of the geomechanical model was performed by taking advantage of the Pawsey Centre’s resources to run numerous simulations in order to derive the sensitivity of the parameters involved when this could not be done analytically. The multi-scale framework developed also required the large computational power of the Pawsey Centre to simulate the complex flow simulations at the microscale, where the microstructure of rocks evolves due to chemical dissolution and precipitation reactions.
List of publications from this project
- Lesueur, M., Poulet, T., & Veveakis, M. (2020). Three-scale multiphysics finite element framework (FE3) modelling fault reactivation. Computer Methods in Applied Mechanics and Engineering, 365, 112988.
- Lin, J.; Sari, M.; Alevizos, S.; Veveakis, M. & Poulet, T. (2020) “A heuristic model inversion for coupled thermo-hydro-mechanical modelling of triaxial experiments” Computers and Geotechnics, Elsevier BV, 2020, 117, 103278
