A Method for Predicting the Dynamic Flow Temperature of Natural Gas Based on Path Search

Abstract

The invention relates to a path search-based temperature prediction method for natural gas dynamic flow in a natural gas pipeline network. First, the grid of the natural gas pipeline network to be predicted is discrete, and by means of actual measurement and other methods, each discrete node in the natural gas pipeline network is determined. Then the dynamic energy equation of natural gas with partial differential form running inside the pipeline is mathematically discretized, and at the same time, the temperature change equation of natural gas with nonlinear form in non-pipeline components is linearly processed to obtain the required linear algebra Equations; after adding the corresponding boundary conditions for the temperature calculation of the natural gas pipeline network, the method based on path search is used to solve the temperature prediction, and the calculation is carried out until the required moment. The present invention has the advantages of fast calculation speed and long predictable time interval at the next moment, and can realize efficient temperature prediction for working conditions with long duration or large fluctuations of natural gas flow state fluctuations.

Description

technical field [0001] The invention relates to a method for predicting the dynamic flow temperature of natural gas based on path search, which is suitable for predicting and measuring the temperature of natural gas in a natural gas pipeline network. Background technique [0002] As a high-quality, clean and efficient fossil energy, natural gas is favored in the context of developing a low-carbon economy. The International Energy Agency (IEA) clearly pointed out that the 21st century is the "golden age of natural gas". In recent years, my country has attached great importance to the development of natural gas and has made great achievements. By the end of 2015, natural gas accounted for 5.9% of my country's energy structure, and the total length of natural gas trunk pipelines was about 64,000 kilometers. At the same time, the "13th Five-Year Plan" for energy development pointed out that my country will continue to increase the construction of natural gas pipelines and furth...

AI Technical Summary

Problems solved by technology

[0004] The advantages and disadvantages of the explicit method are as follows: Advantages: There is only one discrete node on the right side of the mathematical formula used in the solution process or only the value of the temperature to be predicted at the outlet of the component. The solution in computer programming is a numerical value assignment process, no need Multiple iterative calculation process, the calculation process is simple and the calculation speed is fast; Disadvantage: The value of the time step used by the explicit method is limited by the stability condition, and the range of values ​​is small, which can predict the time interval of the next moment shorter

When a personal computer is used to solve a moment, the required calculation time is 10s

When the fluctuation of the flow state of natural gas in the pipeline network is relatively large, if the time step must be set to be less than 10s, obviously, the implicit method cannot predict the natural gas temperature at the next moment before the arrival of the next moment, and loses engineering application value

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