Search

CN-122021420-A - Method and system for rapidly analyzing transportation and distribution capacity of hydrogen-doped natural gas urban pipe network

CN122021420ACN 122021420 ACN122021420 ACN 122021420ACN-122021420-A

Abstract

The invention relates to a method and a system for rapidly analyzing the transmission and distribution capacity of a hydrogen-doped natural gas urban pipe network; the method comprises the steps of determining initial pipe network flow field parameters and reference flow coefficients under the reference working condition without hydrogen addition, calculating the hydrogen addition proportion of each pipe based on the current pipe network flow field parameters, correcting the flow coefficients, updating the pipe network flow field parameters based on the corrected current flow coefficients, and repeating the processes until cut-off conditions are met. According to the invention, the pipeline circulation capacity after hydrogen loading can be directly obtained without complex iteration, so that the rapid calculation can be performed according to the gas source hydrogen loading ratio and the user flow, the calculation flow is greatly simplified, and the calculation efficiency of a large-scale pipe network is remarkably improved.

Inventors

  • QIAN XIAOLEI
  • HUANG XINHUI

Assignees

  • 上海天麦能源科技有限公司

Dates

Publication Date
20260512
Application Date
20260119

Claims (10)

  1. 1. A method for rapidly analyzing the transmission and distribution capacity of a hydrogen-doped natural gas urban pipe network is characterized by comprising the following steps: step S1, constructing a topological structure model of a gas pipe network of a region to be analyzed, wherein the topological structure model comprises nodes and pipelines, and initializing node and pipeline parameters in the topological structure model, wherein the nodes comprise air source nodes and user nodes; Step S2, determining initial pipe network flow field parameters and reference flow coefficients under the reference working condition without hydrogen; s3, calculating the hydrogen loading proportion of each pipeline based on the current pipe network flow field parameters; S4, correcting the current circulation coefficient based on the hydrogen loading proportion of each pipeline, specifically, using a fitting relation constructed based on the hydrogen loading proportion to correct the current circulation coefficient Setting a reference circulation coefficient as a current circulation coefficient in an initial state; Step S5, updating pipe network flow field parameters based on the corrected current flow coefficient, judging whether updating cut-off conditions are met, if yes, entering the next step, otherwise, returning to the step S3; And S6, attaching the pipe network flow field parameters to the pipe network structure model for output.
  2. 2. The method for rapid analysis of capacity of a hydrogen-doped natural gas municipal pipe network according to claim 1, wherein step S2 is performed by initializing the hydrogen-doped ratio in the topology model assuming that the entire gas pipe network is not doped with hydrogen Reference flow coefficient of each pipeline in the state of not adding hydrogen The method comprises the steps of taking the flow coefficient as an initial value, taking a pipe network flow field parameter under a reference working condition as an initial value of the pipe network flow field parameter based on a gas pipe network hydraulic model, wherein the pipe network flow field parameter comprises the pressure P of a node, the mass flow M of a pipeline and/or the flow field coefficient.
  3. 3. The rapid analysis method for the capacity of a hydrogen-doped natural gas municipal pipe network according to claim 2, wherein the current flow coefficient is based on the formula (8) Linear correction is carried out to obtain a corrected flow coefficient under the hydrogen loading working condition ; (8)。
  4. 4. The method for rapid analysis of urban pipeline network transmission and distribution capacity of hydrogen-doped natural gas according to claim 3, wherein the method is applicable to the pressure of urban gas pipeline in medium-pressure operation interval.
  5. 5. The rapid analysis method for the transportation and distribution capacity of the hydrogen-doped natural gas urban pipe network according to claim 4, wherein the medium-pressure operation interval is 0.2-0.4MPa.
  6. 6. The method for rapid analysis of capacity of a hydrogen-doped natural gas municipal pipe network according to claim 5, wherein step S5 comprises the steps of And judging whether the difference between the pipe network flow field parameters before and after updating is smaller than a preset convergence tolerance, if so, determining that the updating cut-off condition is met, entering the next step, otherwise, returning to the step S3.
  7. 7. A rapid analysis platform for the transportation and distribution capacity of a hydrogen-doped natural gas urban pipe network, which is characterized in that the platform is used for realizing the rapid analysis method for the transportation and distribution capacity of the hydrogen-doped natural gas urban pipe network according to any one of claims 1 to 6.
  8. 8. A server for rapidly analyzing the transmission and distribution capacity of a hydrogen-doped natural gas urban pipe network, comprising a processor, wherein the processor is coupled to a memory, the memory stores program instructions, and the method for rapidly analyzing the transmission and distribution capacity of the hydrogen-doped natural gas urban pipe network according to any one of claims 1 to 6 is realized when the program instructions stored in the memory are executed by the processor.
  9. 9. A system for rapidly analyzing the transmission and distribution capacity of a hydrogen-doped natural gas urban pipe network, wherein the system is used for realizing the rapid analysis method for the transmission and distribution capacity of the hydrogen-doped natural gas urban pipe network according to any one of claims 1 to 6.
  10. 10. A computer readable storage medium comprising a program which, when run on a computer, causes the computer to perform the method for rapid analysis of the capacity of a hydrogen-loaded natural gas municipal pipe network of any of claims 1-6.

Description

Method and system for rapidly analyzing transportation and distribution capacity of hydrogen-doped natural gas urban pipe network Technical Field The invention belongs to the technical field of intelligent pipe networks, and particularly relates to a method and a system for rapidly analyzing the transmission and distribution capacity of a hydrogen-doped natural gas urban pipe network. Background An important output result of the gas pipe network transmission and distribution calculation method is a pipe network flow field state. The flow field state of the pipe network mainly refers to pipe network pressure distribution, pipe network flow distribution and pipe network component distribution. The method can obtain whether a low-pressure area exists in the pipe network based on pipe network pressure distribution, can obtain a transmission and distribution bottleneck in the pipe network based on pipe network flow distribution, and can obtain a fuel gas heat value obtained by a user based on pipe network component distribution. The transmission and distribution calculation method of the gas pipe network is highly dependent on the transmission and distribution capacity measurement and calculation method of each pipeline. When the transmission and distribution capacity of a single pipeline is measured and calculated, the relationship between the pressure difference and the flow rate at two ends of the pipeline is generally calculated according to the law of hydraulics, and the relationship is calculated gradually along the flow direction from the air source of a pipe network. In general, in natural gas networks without hydrogen addition, the gas physical parameters can be simplified to be related to pressure and temperature, and the friction coefficient and the flow coefficient can be calculated by a limited iteration convergence mode. However, when hydrogen is injected into a pipe network and the delivery process is to be simulated, the composition of the gas flow becomes a variable factor, and the conventional method has insufficient appearance. Fluctuations in the hydrogen ratio of the gas in the pipeline can also occur when the hydrogen loading ratio of the gas source is changed. The physical properties of hydrogen and the physical properties of the fuel gas component are greatly different, and particularly when the hydrogen loading ratio is large, the physical properties of the mixed gas and the physical properties of the gas without hydrogen loading are greatly different. Thus, in addition to the effect of the hydrogen loading ratio of the gas source on the hydrogen loading ratio throughout the pipeline, the hydrogen loading ratio in the pipeline is also affected by the flow ratio at which the gases are mixed, and the physical properties of the gases in the pipeline are affected by the pressure, temperature and hydrogen loading ratio at the same time. The hydrogen loading ratio in a certain pipeline needs to be calculated after knowing the pipeline flow field, so that the flow coefficient needs to be calculatedRepeated iterations are performed in the process of calculating the friction coefficient and the hydrogen loading ratio. The main problems in the prior art are that firstly, the calculation complexity is high and the iteration efficiency is low, namely, after hydrogen is added, key physical parameters such as gas density, viscosity and the like are changed from a binary function (P, T) to a ternary function (P, T,) And (5) calculating dimension improvement. Meanwhile, the calculation of the friction coefficient depends on the Reynolds number, which is a function of density and viscosity, and a complex nonlinear relation is introduced. In order to solve the flow capacity of a pipe section, it is necessary to iterate the physical properties and the friction coefficient several times, and the calculation load increases sharply. Secondly, the global convergence is difficult, the traditional method needs to perform multiple global iterations on the whole pipe network to simultaneously meet the requirements of pressure balance and component conservation, the calculation flow is long, the convergence is poor, and the requirement of quick simulation in engineering practice is difficult to meet. Third, there is a lack of efficient approximation models for low-ratio loading, facing the complex coupling calculations described above, and the conventional approach lacks efficient simplified models at medium-pressure network, low loading ratios. In summary, however, there are often tens of thousands of pipelines in the working condition, and the increase of the number of pipelines does not increase the calculated amount linearly, but increases in an exponential level, so that common calculation resources cannot support smooth calculation, and the calculation accuracy and the calculation efficiency are difficult to be compatible. Based on the problems, the invention realizes the quick and accurate estimation of the