Dimensionless Stress to Pore Pressure Conversion for Reservoir Simulation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for reservoir simulation often neglect coupled geomechanics, leading to inaccurate predictions of reservoir response to production, and pseudo-representations of structural subsurface changes fail to capture full physics of production-induced interactions.
Innovation Solution
Transforming rock mechanics data from pore compressibility tests into rock compaction tables using Dimensionless Stress to Pore Pressure Conversion (DSPC) to model geomechanical changes due to confining stress in terms of pore pressure, allowing for more accurate simulation of structural and hydrodynamic interactions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If coupled reservoir and geomechanics simulation is used, then prediction accuracy of reservoir response is improved, but computational cost and time consumption increase significantly
Solution Approach 1:
The coupled simulation problem is segmented into two separate simulations: a reservoir simulation and a geomechanics simulation. The reservoir simulator handles fluid flow while the geomechanics simulator handles stress-strain relationships. Data is exchanged between the two simulators at specified intervals rather than solving the full coupled system simultaneously, reducing computational complexity and time requirements while maintaining prediction accuracy.
2Measurement precision
If coupled reservoir and geomechanics simulation is used, then prediction accuracy of reservoir response is improved, but computational resources and financial cost increase
Solution Approach 1:
The computational system is segmented into two independent simulation engines that can be executed separately. The reservoir simulator computes fluid pressure and saturation fields while the geomechanics simulator computes stress and strain fields. This segmentation allows practitioners to use standard reservoir simulators without requiring access to expensive multiphysics simulation software, reducing financial and computational resource requirements.
Solution Approach 2:
An intermediary data exchange mechanism is introduced between the reservoir and geomechanics simulators. pore pressure values from the reservoir simulator are converted to confining stress inputs for the geomechanics simulator, and compaction factors from the geomechanics simulator are converted to pore volume multipliers for the reservoir simulator. This intermediary conversion layer enables communication between the two simulators without requiring full coupling capability.
3Ease of operation
If pore volume and transmissibility multipliers are used, then computational simplicity is improved, but physical accuracy of structural subsurface changes deteriorates
Solution Approach 1:
An intermediary geomechanics simulator is introduced between the simple multiplier approach and the full coupled simulation. The geomechanics simulator computes physically accurate stress-strain-deformation relationships under varying confining stress conditions, and these results are then converted to pore volume multipliers that can be used in the reservoir simulator. This intermediary step preserves physical accuracy while maintaining the simplicity of using multipliers in the reservoir simulation.
Solution Approach 2:
The approach transforms the input parameters from the reservoir simulator (pore pressure) to the appropriate parameters for the geomechanics simulator (confining stress), and then transforms the output parameters from the geomechanics simulator (strain, compaction) back to the appropriate parameters for the reservoir simulator (pore volume multiplier). This parameter transformation chain enables physically accurate results while maintaining compatibility with standard reservoir simulation workflows.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enhances the accuracy of reservoir simulation models by capturing geomechanical changes due to pore pressure, reducing the need for additional data and simplifying the modeling process while maintaining high accuracy, thus improving the prediction of well production and production drive mechanisms.
Implementation Method 1
Transforming rock mechanics data from pore compressibility tests into rock compaction tables using Dimensionless Stress to Pore Pressure Conversion (DSPC) to model geomechanical changes due to confining stress in terms of pore pressure
Data Source
AI summary
Systems and methods of the present disclosure are directed to reservoir simulation modeling using upon rock compaction tables derived from physical pore compressibility tests. The illustrative methods transform rock mechanics-based pore compressibility tests into compliant rock compaction tables for reservoir simulators using Dimensionless Stress to Pore Pressure Conversion, to thereby transfer geomechanical changes due to confining stress into expressions of geomechanical changes due to pore pressure.