Thermal Adaptive Implicit Method for Reservoir Simulation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current reservoir simulation techniques, such as FIM, IMPES, and AIM, face challenges in thermal systems with complex CFL conditions, requiring improved simulation run time and memory usage, especially in decoupling CFL conditions for multi-phase systems with inter-phase mass transfer and capillarity effects.
Innovation Solution
A method involving a thermal adaptive implicit method (TAIM) that calculates multiple CFL conditions concurrently, decouples CFL conditions in each cell, and expands CFL conditions to include temperature effects, enabling efficient simulation of multi-phase systems with mass transfer.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If traditional reservoir simulation techniques (FIM, IMPES, AIM) are used for thermal systems, then simulation coverage of multi-phase systems is achieved, but simulation run time increases and memory usage increases
Solution Approach 1:
The patent segments the complex thermal reservoir simulation into distinct computational components by calculating multiple CFL conditions (temperature CFL, composition CFL, saturation CFL) concurrently for different aspects of the multi-phase system. This segmentation allows each condition to be evaluated and handled independently, improving computational efficiency while maintaining comprehensive simulation coverage of thermal, compositional, and saturation effects.
2Adaptability or versatility
If traditional reservoir simulation techniques (FIM, IMPES, AIM) are used for thermal systems, then simulation coverage of multi-phase systems is achieved, but memory usage increases
Solution Approach 1:
The patent segments the computational requirements into separate CFL condition calculations for temperature, composition, and saturation. By treating these as distinct, concurrently calculable conditions rather than a monolithic system, the patent reduces the peak memory requirements while still capturing all thermal, compositional, and phase behavior effects in the reservoir simulation.
Solution Approach 2:
The patent changes the computational parameters by introducing multiple concurrent CFL conditions (temperature CFL, composition CFL, saturation CFL) that can be calculated independently. This parameter transformation allows the simulation to maintain comprehensive multi-phase thermal system coverage while using memory more efficiently through parallel, modular condition evaluation.
3Measurement precision
If CFL conditions are calculated for thermal systems with mass transfer and capillarity, then simulation accuracy is improved, but calculation complexity increases
Solution Approach 1:
The patent segments the complex CFL condition calculations into three distinct types: temperature CFL for thermal effects, composition CFL for mass transfer, and saturation CFL for capillarity. By segmenting these calculations, the patent maintains high simulation accuracy for all phenomena while reducing calculation complexity through modular, concurrent evaluation of each condition type.
Solution Approach 2:
The patent transforms the complex coupled thermal-compositional-capillary simulation into a set of parameterized CFL conditions that can be calculated concurrently. This parameter change approach maintains accuracy by explicitly accounting for temperature, composition, and saturation effects while simplifying the overall calculation structure through standardized condition evaluation.
4Productivity
If multiple CFL conditions are calculated concurrently for each cell, then simulation efficiency is improved, but computational requirements increase
Solution Approach 1:
The patent segments the computational workload into distinct CFL condition calculations (temperature, composition, saturation) that can be performed concurrently at the cell level. This segmentation improves simulation efficiency by enabling parallel computation while managing computational requirements through modular organization of the calculation tasks.
Solution Approach 2:
The patent applies partial implicit treatment by calculating multiple CFL conditions concurrently for each cell, applying implicit methods selectively where needed rather than uniformly across the entire system. This partial action approach improves efficiency by focusing computational effort on critical conditions while maintaining acceptable accuracy, thereby improving simulation efficiency without excessive computational requirements.
Data Source
AI summary
The invention relates to a method of performing an oilfield operation of an oilfield having at least one wellsite, each wellsite having a wellbore penetrating a subterranean formation for extracting fluid from an underground reservoir therein. The method includes determining a time-step for simulating the reservoir, the reservoir being represented as a plurality of gridded cells and being modeled as a multi-phase system using a plurality of partial differential equations, calculating a plurality of Courant-Friedrichs-Lewy (CFL) conditions of the reservoir model corresponding to the time-step, the plurality of CFL conditions comprising a temperature CFL condition, a composition CFL condition, and a saturation CFL condition, simulating a first cell of the plurality of gridded cells with an Implicit Pressure, Explicit Saturations (IMPES) system, and simulating a second cell of the plurality of gridded cells with a Fully Implicit Method (FIM) system.