Speaker
Description
Coupled fluid-flow and geomechanical simulations are essential for assessing the safety and effectiveness of reservoir operations. In fractured reservoirs, the presence of a large number of fractures makes fully resolved 2D and 3D coupled simulations of flow and deformation computationally infeasible. In such settings, efficient reduced-order methods that accurately approximate the governing processes are required.
Recently, two closely related methods have been developed to efficiently model either the pressure field or the mechanical response of highly fractured rock. The fracture displacement basis function (FDBF) method represents the displacement field as a superposition of numerically computed basis functions based on predefined displacement profiles. Only a few degrees of freedom per fracture-one shear slip component, one tensile opening component, and additional skewness terms-are required to capture the global displacement field, the shear displacement, and tensile opening when solving slip criteria formulated in an integral sense. Similarly, the fracture pressure basis function method employs pressure basis functions to efficiently solve for the pressure field in complex fracture domains.
Both methods are scale-independent and mesh-less; therefore, they can handle fracture networks with high length-scale heterogeneity. Coupling the two approaches requires accounting for permeability changes due to variations in fracture aperture on the flow side, as well as the influence of fluid pressure on mechanical forces and slip criteria. We investigate whether direct or iterative coupling strategies are more appropriate in this framework and examine the role of relaxation in the Coulomb friction law and the flow solver to represent delayed mechanical and hydraulic responses, respectively.
We apply the coupled model to various fracture patterns and show that approximate pressure, displacement, and stress fields can be computed efficiently, opening the possibility of large-scale coupled flow and geomechanics simulations in complex fractured systems
| Country | Switzerland |
|---|---|
| Acceptance of the Terms & Conditions | Click here to agree |
