Discrete Fracture Modeling in Porous Media Systems

Discrete fracture modelling addresses the explicit representation of individual fractures within a porous matrix, enabling accurate prediction of flow and transport in naturally and hydraulically fractured formations. Unlike continuum or dual‐continuum approaches, this class of models treats fractures as lower‐dimensional entities embedded in a higher‐dimensional rock matrix, honouring their geometry, connectivity and aperture distribution. The resulting systems of coupled equations capture matrix‐to‐fracture exchange, anisotropic permeability and complex flow regimes under single‐ and multiphase conditions. Key challenges include the generation of representative fracture networks from field or image data, the handling of large conductivity contrasts, and the need for computationally efficient discretisation schemes that preserve mass conservation on unstructured or hybrid grids. Recent advances have integrated geomechanical coupling to simulate fracture propagation and shear reactivation, multiscale methods to bridge core‐scale detail with field‐scale performance, and enhanced transport physics such as gas slippage and diffusive effects in narrow apertures. Applications span subsurface energy production, carbon storage, groundwater management and geothermal energy extraction, each demanding tailored fracture representations to predict deliverability, breakthrough behaviour and long‐term sustainability.

Research from Nature Portfolio

Recent studies have extended discrete fracture modelling to account for the full complexity of non‐planar networks in low‐permeability shales. A comprehensive model has been developed that integrates real gas transport mechanisms—advection, desorption, Knudsen diffusion and slip flow—within arbitrarily curved fracture geometries. This framework demonstrates that simple planar approximations can substantially overestimate productivity, and that the appearance and sharpness of transitional “humps” in rate‐transient analysis directly reflect fracture irregularity and connectivity. The work highlights how mechanistic coupling of multiple gas‐phase phenomena prolongs transition‐flow regimes and underscores the importance of generating highly connected, non‐planar fracture systems for optimised resource recovery.

Discrete Fracture Modeling in Porous Media Systems publication trend

The graph below shows the total number of articles in discrete fracture modeling in porous media systems across all publications each year (not limited to Nature Index journals).

Technical terms

Discrete fracture model (DFM): A numerical approach that represents fractures explicitly as lower‐dimensional features within a porous matrix to simulate fluid flow and transport.

Embedded discrete fracture model (EDFM): A variant of DFM that embeds fractures into a Cartesian or structured grid, avoiding mesh conformity while ensuring local mass conservation.

Projection‐based EDFM (pEDFM): An advanced EDFM that automatically adjusts matrix transmissibility and adds matrix‐fracture connections to capture arbitrary conductivity contrasts.

Multicontinuum modelling: A framework that treats fractures, matrix and possibly vugs as overlapping continua, each with its own flow equations and inter‐continuum transfer terms.

Knudsen diffusion: A gas transport mechanism that dominates when the fracture aperture is comparable to the mean free path of molecules, leading to molecule‐wall collisions.

Slip flow: A gas flow regime in narrow apertures where velocity at the fracture walls deviates from the classical no‐slip condition, enhancing apparent permeability.

References

1. A Comprehensive Model for Real Gas Transport in Shale Formations with Complex Non-planar Fracture Networks. Scientific Reports (2016).
2. An efficient 3D cell-based discrete fracture-matrix flow model for digitally captured fracture networks. International Journal of Coal Science & Technology (2023).
3. Projection-based Embedded Discrete Fracture Model (pEDFM). Advances in Water Resources (2017).
4. An Open-Source Code for Fluid Flow Simulations in Unconventional Fractured Reservoirs. Geosciences (2021).