An Embedded Discrete Fracture Model (EDFM) Approach Using a Multipoint Flux Approximation (MPFA) Formulation in Naturally Fractured Reservoirs

Resumo

Naturally Fractured Reservoirs (NFR) form part of major water and energy sources around the world.
However, due to their geological complexity and high-contrast permeability, it is difficult to obtain accurate
forecasts and estimates of their production behavior. The numerical modeling and simulation of such reservoirs,
involving fractures of different scales is a great challenge from a mathematical and numerical point of views. In
this context, a very interesting way of representing fractures is through the Embedded Discrete Fracture Model
(EDFM). The strategy was initially developed as a technique that directly incorporates fractures in a conventional
structured mesh, bypassing the additional computational cost of using unstructured meshes, and remaining
compatible with the complex fracture geometries, such as non-planar fractures and fractures with variable aperture.
In this context, our simulation tool incorporates a Multi-Point Flux Approximation method via a diamond stencil
(MPFA-D), which is a very flexible and robust formulation capable of handling highly heterogeneous and
anisotropic domains using general polygonal meshes to solve the pressure equation. To verify our formulation, we
solve some representative problems found in the literature.