Multiphase Pipeline Flow Prediction Beyond CFL Time-Step Limits
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current computational fluid dynamics (CFD) simulations for multiphase flows in pipeline transport systems face challenges with numerical stability, particularly due to the Courant-Friedrichs-Lewy (CFL) condition, which restricts time step sizes and increases computational load, leading to inaccurate and inefficient predictions of fluid behavior.
Innovation Solution
A computer-implemented method that uses a polynomial to spatially reconstruct mass fluxes, allowing for explicit numerical solutions independent of the CFL condition, ensuring positivity of mass and enabling larger time steps without compromising stability, thus improving the accuracy and efficiency of multiphase flow simulations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If explicit numerical solution schemes are used for multiphase flow simulation, then computational efficiency and accuracy are improved, but numerical stability deteriorates due to CFL condition restrictions
Solution Approach 1:
The patent transforms the explicit numerical solution scheme by changing the parameter of time step size independence from CFL condition restrictions. This is achieved through a modified numerical formulation that decouples the stability constraint from the time step selection, allowing larger time steps without sacrificing numerical stability while maintaining computational efficiency.
Solution Approach 2:
The patent replaces the traditional explicit numerical solution mechanism constrained by CFL conditions with a modified numerical scheme that uses a different computational approach. The substitution involves transforming the governing equations and solution methodology to eliminate the CFL stability restriction while preserving the explicit scheme's computational advantages.
2Loss of time
If larger time steps are used to reduce computational load, then productivity increases, but measurement precision deteriorates due to CFL condition limitations
Solution Approach 1:
The patent changes the parameter relationship between time step size and simulation accuracy by modifying the numerical solution scheme. The transformed scheme allows time step sizes to be increased for reducing computational time while maintaining simulation accuracy through the stabilized numerical formulation that is independent of CFL restrictions.
3Measurement precision
If CFD simulations are performed for long-distance multiphase flow transport, then prediction accuracy is improved, but computational load increases due to complex non-linear interactions
Solution Approach 1:
The patent transforms the computational parameters by introducing a numerical scheme that is independent of CFL conditions, enabling the use of larger time steps. This reduces the total number of computational steps required for long-distance multiphase flow simulations while maintaining prediction accuracy, thereby decreasing computational load and energy consumption.
Data Source
Figure 1
Figure 2a~2b
Figure 3a
AI summary
This invention relates to an autonomous flow management system for regulating a multiphase flow in a pipeline-based transport system which utilises a novel computer-implemented method for predicting the multiphase fluid behaviour in the pipeline-based transport system. The computer-implemented method comprises applying a one-dimensional computational fluid dynamic applying a finite volume method in the solver and which estimates the mass flux out of the finite control volumes by i) applying a polynomial to spatially reconstruct the mass present in each finite control volume, ii) reconstructing the flow velocity as a function of the x-component of the flow velocity vector to determine a domain of dependence for each finite control volume representing the distance the fluid has travelled during a time step, and iii) sum the spatially reconstructed mass being present in the domain of dependence for each finite control volume and assume the summarised mass passes out of the respective finite control volume over the applied time step.