Temperature prediction method during dynamic flowing of natural gas in natural gas pipeline network on the basis of path search

Abstract

The invention relates to a temperature prediction method during the dynamic flowing of natural gas in a natural gas pipeline network on the basis of path search. The method comprises the following steps that: firstly, carrying out grid dispersion on a natural gas pipeline network to be predicted; by means of a practical measurement method, determining the hydraulic parameter of each dispersing node in the natural gas pipeline network; then, carrying out mathematic dispersion on a dynamic energy equation which is operated by natural gas of a partial differential form in the pipeline; meanwhile,carrying out linear processing on the temperature change equation of the natural gas of a nonlinear form in a non-pipeline element to obtain a required linear algebra equation set; and after a corresponding natural gas pipeline network calculation boundary condition is increased, adopting a method based on path search to solve temperature prediction until the required moment is calculated. The method has two advantages of high calculation speed and long time interval of a next predictable moment, and working conditions of long volatility persistence time or large fluctuation of a natural gasflowing state can be subjected to efficient temperature prediction.

Description

technical field [0001] The invention relates to a path search-based method for predicting the temperature of natural gas in a natural gas pipeline network during dynamic flow, which is suitable for predicting and measuring the temperature of natural gas in the 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 constru...

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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