Dynamic Time Step Optimization for Reservoir Flow Simulation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current flow modeling algorithms for oil/gas reservoirs primarily rely on duration-based time stepping, which can lead to inaccurate simulations due to subjective user input and neglect of quality criteria, affecting the representation of transient effects and pressure frequency content.
Innovation Solution
A method that determines time steps based on quality criteria, including root mean square error, mean absolute error, and frequency analysis, to ensure accurate simulation by adjusting time steps according to the variability and relevance of control data, thereby enhancing simulation quality and accuracy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of time
If duration-based time stepping is used to limit simulation time, then simulation duration is reduced, but simulation accuracy deteriorates
Solution Approach 1:
The time step selection is made dynamic by adjusting it based on the quality criterion evaluation. Instead of using fixed duration-based time steps, the method dynamically selects time step sizes that satisfy both time efficiency and accuracy requirements by evaluating whether the selected time step produces simulation results within an acceptable error margin of the control data.
Solution Approach 2:
The method changes the parameter selection criterion from purely duration-based to quality-based. By evaluating the quality criterion (error margin) and adjusting the time step parameter accordingly, the system achieves optimal balance between simulation speed and accuracy, selecting larger time steps when accuracy is sufficient and smaller time steps when higher precision is needed.
2Ease of operation
If user-defined number of steps is used for time stepping, then simulation control is improved, but simulation quality deteriorates due to subjective input
Solution Approach 1:
The method introduces feedback by evaluating the quality criterion (error margin) of the simulation results and using this information to adjust subsequent time step selections. This automated feedback loop replaces subjective user input with objective quality-based adjustments, ensuring simulation accuracy while maintaining ease of operation through automated optimization.
3Productivity
If flexible stepping logic based on convergence function is used, then simulation efficiency is improved, but simulation accuracy deteriorates due to long time steps
Solution Approach 1:
The method makes time step selection dynamic by continuously evaluating the quality criterion and adjusting time step sizes accordingly. This dynamic adjustment ensures that time steps are neither too large (which would lose accuracy) nor too small (which would reduce efficiency), but rather optimized for each specific simulation condition to achieve both efficiency and accuracy.
Data Source
Figure 1
Figure 2a~2b
Figure 2c
AI summary
The present invention relates to a method for optimizing a modeling of flows within a reservoir for optimization of oil/gas production, the method comprising: /a/ receiving (302) a first time step; /b/ receiving (301) flow condition for at least one well connected to the reservoir; /c/ selecting data (204, 208) in the control data that is applicable to the first time step; /d/ determining (309, 319, 329) at least one quality value based on the selected data; /e/ if a quality criterion is not met (310, 330) based on the quality value, determining a second time step within the first time step and reiterating step /c/ to /e/ with the second time step as the first time step; /f/ if the quality criterion is met (310, 330) based on the quality value, performing a modeling (104) of flows within the reservoir based on said first time step.