EOR Injection Modeling for Viscous Fingering on Coarse Reservoir Grids
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing EOR techniques face challenges in accurately and efficiently modeling viscous fingering effects due to varying EOR agent concentrations, leading to inefficient oil recovery and potential water breakthrough, which conventional methods fail to address effectively.
Innovation Solution
A computationally efficient method for modeling viscous fingering by simulating EOR agent injection at multiple concentrations using upscaling techniques, applying transport coefficient functions to modify fluid mobility based on concentration, and employing coarse simulation grids to capture these effects.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If high-resolution simulation grid is used to accurately simulate viscous fingering, then simulation accuracy is improved, but computational time and resources become impractical
Solution Approach 1:
The patent changes the parameter of grid resolution by introducing an upscaling factor that transforms fine-grid viscous fingering effects into equivalent coarse-grid representations. This allows the simulation to use coarse grids (reducing computational time) while still capturing the essential physics of viscous fingering through modified relative permeability functions that incorporate the upscaling factor and concentration gradients.
Solution Approach 2:
The patent introduces an intermediary upscaling factor as a mediator between fine-scale viscous fingering physics and coarse-scale simulation. This factor acts as a bridge that transfers the effects of high-resolution fingering phenomena into the coarse-grid model through modified relative permeability relationships, allowing accurate representation without requiring fine-grid resolution.
2Productivity
If conventional upscaling methods are used to reduce computational cost, then computational efficiency is improved, but accuracy deteriorates when EOR agent concentration varies
Solution Approach 1:
The patent applies local quality by making the upscaling factor and relative permeability modifications concentration-dependent. Instead of using uniform upscaling across the entire domain, the method locally adapts the upscaling factor based on the local EOR agent concentration and its gradients. This allows the coarse-grid model to accurately represent viscous fingering effects in regions where concentration variations are significant while maintaining computational efficiency.
Solution Approach 2:
The patent introduces dynamics by making the upscaling factor a dynamic variable that changes with concentration gradients rather than being a static parameter. The upscaling factor is computed based on local concentration differences and evolves throughout the simulation, allowing the model to adapt to changing flow conditions and concentration profiles, thereby maintaining accuracy under varying EOR agent injection scenarios.
3Quantity of substance
If chase water is injected to push EOR agent through reservoir, then EOR agent usage is reduced, but viscous fingering increases due to higher chase water mobility
Solution Approach 1:
The patent applies feedback by using the simulated concentration fields and flow patterns to dynamically adjust the upscaling factor and relative permeability modifications. The model continuously monitors the development of viscous fingering through concentration gradients and uses this information to adjust the upscaling parameters, creating a feedback loop that prevents excessive fingering while maintaining the benefits of chase water injection for reducing EOR agent usage.
Data Source
Figure 1
Figure 2A~2D
Figure 3
AI summary
A method, apparatus, and program product model an Enhanced Oil Recovery (EOR) process in a subsurface volume by computer modeling a variable-concentration injection of an EOR agent in multiple grid blocks of a reservoir grid, where the variable-concentration injection includes an injection of the EOR agent at multiple injection concentrations. For a first grid block among the multiple grid blocks within which EOR agent is present, a viscous fingering effect is modeled by modifying a fluid mobility in the first grid block based at least in part upon the injection concentration of the EOR agent present in the first grid block.