Subsurface Hydraulic Fracture Simulation with 3D Rock Discontinuities
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional reservoir simulators fail to accurately model complex three-dimensional hydraulic fractures and multiscale subterranean rock discontinuities, leading to loss of spatial information and numerical instability issues due to upscaling of rock discontinuities and simplistic representation of two-dimensional geometries.
Innovation Solution
The implementation of embedded discrete fracture modeling (EDFM) techniques, which convert discrete fracture network and hydraulic fracture data into a digital EDFM format, allowing for the creation of a computational domain separate from conventional simulator modules to generate a simulation of subterranean regions with complex fracture geometries, including non-neighboring connections between matrix, rock discontinuity, and hydraulic fracture cells.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If conventional dual porosity and dual permeability (DPDK) models upscale rock discontinuities in reservoir simulation models, then the model complexity is reduced and computational efficiency is improved, but the resolution of three-dimensional geometries is severely reduced and spatial information such as connectivity and intensity is lost
Solution Approach 1:
The patent segments the reservoir model into matrix blocks and discrete fracture networks, where each fracture is represented as a separate entity with its own geometric properties. This segmentation allows the model to maintain three-dimensional fracture geometries while using efficient numerical methods for computation, resolving the contradiction between model detail and computational efficiency.
Solution Approach 2:
The patent transitions from two-dimensional upscaling approaches to three-dimensional discrete fracture network modeling. By representing fractures as three-dimensional objects with explicit geometry, orientation, and connectivity, the model preserves spatial information while using dimensionality-aware numerical methods to maintain computational efficiency.
2Manufacturing precision
If local grid refinement is used to represent fracture behavior by using progressive refinement in a grid, then the representation of two-dimensional fracture geometry is improved, but the ability to represent three-dimensional rock discontinuities is lost because the method was designed for two-dimensional geometry
Solution Approach 1:
The patent extends fracture representation from two-dimensional local grid refinement to three-dimensional discrete fracture networks. Fractures are modeled as three-dimensional objects with explicit geometry, orientation, and spatial extent, allowing the model to represent complex three-dimensional rock discontinuities while maintaining geometric precision through the discrete fracture network framework.
3Manufacturing precision
If unstructured gridding is used to generate a grid that conforms to three-dimensional geometries of rock discontinuities, then the representation of three-dimensional hydraulic fractures and rock discontinuities is improved, but large computational overhead is demanded when running field cases with high numbers of rock discontinuities and numerical instability problems occur due to gridblocks having small sizes
Solution Approach 1:
The patent segments the computational domain into matrix blocks and discrete fracture networks, allowing each to be modeled with appropriate numerical methods. This segmentation avoids the need for fine unstructured gridding throughout the entire domain, reducing computational overhead while maintaining geometric precision where it matters most—in the fracture representations.
Solution Approach 2:
The patent uses dimensionality-aware modeling where fractures are represented as three-dimensional objects embedded in the matrix grid. This approach allows the use of structured or semi-structured grids in the matrix domain while representing fractures with their true three-dimensional geometry, avoiding the computational burden of fully unstructured fine-gridded models.
4Productivity
If conventional reservoir simulators are used, then the simulation process is simple and computationally efficient, but accurate modeling of complex three-dimensional hydraulic fractures and multiscale subterranean rock discontinuities is failed resulting in loss of spatial information
Solution Approach 1:
The patent segments the reservoir system into matrix and fracture components, with the discrete fracture network representing complex three-dimensional geometries explicitly. This segmentation allows conventional simulator efficiency to be maintained in the matrix domain while adding geometric accuracy where needed through the discrete fracture representation and specialized flow equations.
Solution Approach 2:
The patent enhances conventional simulators by incorporating three-dimensional discrete fracture network representations that capture complex geometries, orientations, and connectivities. This dimensional enhancement allows accurate modeling of three-dimensional fracture systems while using efficient numerical methods adapted for discrete fracture modeling.
Data Source
AI summary
Systems and methods for simulating subterranean regions having multi-scale, complex fracture geometries in a realistic simulation environment, which includes in the modeling process three-dimensional multi-scale rock discontinuities, hydraulic fractures, and heterogenous reservoir properties. Non-intrusive embedded discrete fracture modeling formulations are applied in conjunction with commercial or in-house simulators to efficiently and accurately model subsurface characteristics including three-dimensional geometries having combinations of complex hydraulic fractures and multi-scale rock discontinuities.