CN115879324B

CN115879324B - Simulation method, simulation platform and medium for urban gas multi-stage pipe network

Info

Publication number: CN115879324B
Application number: CN202310113798.XA
Authority: CN
Inventors: 刘韶鹏; 王长欣; 吴连奎; 田淑明; 赵洪斌; 康天; 王庆涛
Original assignee: Beijing Yunlu Technology Co Ltd
Current assignee: Beijing Yunlu Technology Co Ltd
Priority date: 2023-02-15
Filing date: 2023-02-15
Publication date: 2023-05-23
Anticipated expiration: 2043-02-15
Also published as: CN115879324A

Abstract

The application relates to a simulation method, a simulation platform and a medium of a multi-stage pipe network of urban fuel gas. Providing a first-level to third-level system with sequentially reduced operation authority. And verifying the user operation rights. For the first-level authority, an urban trunk model is established by a first-level system, and simulation analysis is carried out to obtain simulation data of each trunk node. For the second-level authority, establishing a jurisdiction model by using a second-level system; and obtaining simulation data of corresponding trunk nodes in the urban trunk model, and performing simulation analysis by using the simulation data as boundary conditions to obtain simulation data of nodes in the jurisdiction. For the third-level authority, a management unit model is established by a third-level system; and obtaining simulation data of the corresponding district node in the district model, and performing simulation analysis by using the simulation data as boundary conditions to obtain the simulation data of the management unit node. Therefore, nested hierarchical simulation and operation can be carried out according to the hierarchical management architecture of the urban gas pipe network, pipe network data of all levels are fully utilized across stages, high-efficiency overall regulation and control are achieved, and the calculation cost is remarkably reduced.

Description

Simulation method, simulation platform and medium for urban gas multi-stage pipe network

Technical Field

The present application relates to a modeling simulation method, a modeling simulation system and a medium for an urban public facility pipe network, and more particularly to a simulation method, a simulation platform and a medium for an urban gas multi-stage pipe network.

Background

The urban gas pipe network is complicated and comprises different pressures, pipe diameters, equipment information and monitoring system information. For convenience of management, a GIS (geographic information system) system is usually built for an urban gas pipe network so as to uniformly manage information such as pipe network, valves, gate wells, construction ages, materials and the like. Although gas enterprises begin to purchase simulation software in a unified way, the main pipe and the main loop of the city are usually emphasized in simulation analysis.

The large-scale city pipe network has complex pressure level and is transmitted to end users through gate stations, pipe networks, gas storage facilities, pressure regulating station boxes, sluice wells, management facilities and monitoring systems in the multi-stage pipe networks. If the integrated calculation is required to be carried out on the pipe network system from the trunk to the cell level branch of the large-scale city, the calculation nodes are very many, the data of the monitoring system are complex, a large amount of data are required to be processed behind the simulation interactive interface, the integrated calculation load is very large, the simulation speed is very slow, and the hardware requirement and the calculation force requirement on the processor are very high.

Although management units in some jurisdictions in the city can purchase some gas pipe network management software, the management units are split with a simulation platform of a main pipe network, are limited by local calculation power and data resources, and can only perform rough and simple simulation in the jurisdictions.

Disclosure of Invention

The present application is provided to solve the above-mentioned problems occurring in the prior art.

The simulation method, the simulation platform and the medium can perform nested hierarchical simulation and operation according to a hierarchical management architecture of the urban gas pipeline network, can rapidly perform accurate simulation on the pipeline network, rapidly diagnose abnormal conditions of the pipeline network and auxiliary structures, are beneficial to fully utilizing pipeline network simulation data of all levels across levels, perform efficient overall regulation and control on the pipeline network, and remarkably reduce calculation cost.

According to a first scheme of the application, a simulation method of a multi-stage pipe network of urban fuel gas is provided. The simulation method comprises the following steps. The first-stage simulation system, the second-stage simulation system and the third-stage simulation system with sequentially reduced operation authority are provided, so that the first-stage simulation system can acquire simulation data of the second-stage simulation system and the third-stage simulation system. The user's operational rights are verified. Under the condition that a user has primary authority, the primary simulation system is utilized to acquire pipe network data acquired by a GIS system and an SCADA monitoring system for DN500 and above urban trunk pipe networks and associated auxiliary structures, and accordingly, an urban trunk simulation model of the urban gas pipe network is established. And performing simulation analysis on the urban trunk simulation model to obtain simulation data of each trunk node.

Under the condition that the user has the second-level authority, the second-level simulation system is utilized to acquire pipe network data acquired by the GIS system and the SCADA monitoring system for the jurisdictional pipe network of DN300-500 of the jurisdiction and associated auxiliary structures, and accordingly, a jurisdictional simulation model of the urban gas pipe network is established. And acquiring simulation data of trunk nodes corresponding to boundary conditions of the district simulation model in the city trunk simulation model. And carrying out simulation analysis on the district simulation model by using the simulation data of the corresponding trunk nodes as boundary conditions so as to obtain the simulation data of each district node. Under the condition that a user has three-level authority, the three-level simulation system is utilized to acquire pipe network data acquired by the GIS system and the SCADA monitoring system for the management unit pipe network of DN50-300 of the management unit under the jurisdiction and associated auxiliary structures, and accordingly, a management unit simulation model of the urban gas pipe network is established. And obtaining simulation data of district nodes corresponding to boundary conditions of the management unit simulation model in the district simulation model of the district to which the management unit belongs. And carrying out simulation analysis on the management unit simulation model by using the simulation data of the corresponding district node as a boundary condition so as to obtain the simulation data of each management unit node.

According to a second scheme of the application, a simulation platform of the urban gas multi-stage pipe network is provided. The simulation platform includes an interface and at least one processor. The interface is configured to receive pipe network information from a GIS system and a SCADA monitoring system of the urban gas multi-stage pipe network. The at least one processor is configured to perform a simulation method of a municipal gas multi-stage pipe network according to various embodiments of the application. The simulation method comprises the following steps. The first-stage simulation system, the second-stage simulation system and the third-stage simulation system with sequentially reduced operation authority are provided, so that the first-stage simulation system can acquire simulation data of the second-stage simulation system and the third-stage simulation system. The user's operational rights are verified. Under the condition that a user has primary authority, the primary simulation system is utilized to acquire pipe network data acquired by a GIS system and an SCADA monitoring system for DN500 and above urban trunk pipe networks and associated auxiliary structures, and accordingly, an urban trunk simulation model of the urban gas pipe network is established. And performing simulation analysis on the urban trunk simulation model to obtain simulation data of each trunk node. Under the condition that the user has the second-level authority, the second-level simulation system is utilized to acquire pipe network data acquired by the GIS system and the SCADA monitoring system for the jurisdictional pipe network of DN300-500 of the jurisdiction and associated auxiliary structures, and accordingly, a jurisdictional simulation model of the urban gas pipe network is established. And acquiring simulation data of trunk nodes corresponding to boundary conditions of the district simulation model in the city trunk simulation model. And carrying out simulation analysis on the district simulation model by using the simulation data of the corresponding trunk nodes as boundary conditions so as to obtain the simulation data of each district node. Under the condition that a user has three-level authority, the three-level simulation system is utilized to acquire pipe network data acquired by the GIS system and the SCADA monitoring system for the management unit pipe network of DN50-300 of the management unit under the jurisdiction and associated auxiliary structures, and accordingly, a management unit simulation model of the urban gas pipe network is established. And obtaining simulation data of district nodes corresponding to boundary conditions of the management unit simulation model in the district simulation model of the district to which the management unit belongs. And carrying out simulation analysis on the management unit simulation model by using the simulation data of the corresponding district node as a boundary condition so as to obtain the simulation data of each management unit node.

According to a third aspect of the present application, there is provided a computer readable medium having stored thereon computer executable instructions which, when executed by a processor, implement a simulation method for a multi-stage pipe network for urban gas according to various embodiments of the present application. The simulation method comprises the following steps. The first-stage simulation system, the second-stage simulation system and the third-stage simulation system with sequentially reduced operation authority are provided, so that the first-stage simulation system can acquire simulation data of the second-stage simulation system and the third-stage simulation system. The user's operational rights are verified. Under the condition that a user has primary authority, the primary simulation system is utilized to acquire pipe network data acquired by a GIS system and an SCADA monitoring system for DN500 and above urban trunk pipe networks and associated auxiliary structures, and accordingly, an urban trunk simulation model of the urban gas pipe network is established. And performing simulation analysis on the urban trunk simulation model to obtain simulation data of each trunk node. Under the condition that the user has the second-level authority, the second-level simulation system is utilized to acquire pipe network data acquired by the GIS system and the SCADA monitoring system for the jurisdictional pipe network of DN300-500 of the jurisdiction and associated auxiliary structures, and accordingly, a jurisdictional simulation model of the urban gas pipe network is established. And acquiring simulation data of trunk nodes corresponding to boundary conditions of the district simulation model in the city trunk simulation model. And carrying out simulation analysis on the district simulation model by using the simulation data of the corresponding trunk nodes as boundary conditions so as to obtain the simulation data of each district node. Under the condition that a user has three-level authority, the three-level simulation system is utilized to acquire pipe network data acquired by the GIS system and the SCADA monitoring system for the management unit pipe network of DN50-300 of the management unit under the jurisdiction and associated auxiliary structures, and accordingly, a management unit simulation model of the urban gas pipe network is established. And obtaining simulation data of district nodes corresponding to boundary conditions of the management unit simulation model in the district simulation model of the district to which the management unit belongs. And carrying out simulation analysis on the management unit simulation model by using the simulation data of the corresponding district node as a boundary condition so as to obtain the simulation data of each management unit node.

According to the simulation method, the simulation platform and the medium of the urban gas multi-stage pipe network, by providing the primary simulation system, the secondary simulation system and the tertiary simulation system with sequentially reduced operation authorities, the related simulation data of the simulation model of the superior simulation system are used as boundary conditions of the simulation model of the present stage simulation system, simulation analysis results are shared by being lowered step by step as required, and meanwhile, calculation loads are lowered step by step, so that nested hierarchical simulation and operation can be performed according to the hierarchical management architecture of the urban gas pipe network, accurate simulation can be performed on the pipe network, abnormal conditions of the pipe network and the auxiliary structures can be rapidly diagnosed, the primary simulation system can acquire simulation data of the secondary simulation system and the tertiary simulation system, the pipe network simulation data of each stage can be fully utilized across the stage, efficient integral regulation and control of the pipe network can be performed, and the calculation cost is remarkably reduced.

Drawings

In the drawings, which are not necessarily drawn to scale, like numerals may describe similar components in different views. The same reference numerals with letter suffixes or different letter suffixes may represent different instances of similar components. The accompanying drawings illustrate various embodiments by way of example in general and not by way of limitation, and together with the description and claims serve to explain the disclosed embodiments. Such embodiments are illustrative and not intended to be exhaustive or exclusive of the present apparatus or method.

FIG. 1 shows a flow chart of a simulation method of a multi-stage pipe network for urban gas according to an embodiment of the application;

FIG. 2 shows a hierarchical schematic view of a city gas multi-stage piping network in accordance with an embodiment of the present application;

FIG. 3 illustrates a flowchart of an example of obtaining simulation data of a trunk node in the city trunk simulation model corresponding to boundary conditions of a jurisdictional simulation model, in accordance with an embodiment of the present application;

FIG. 4 shows a schematic diagram of a transition point according to an embodiment of the present application;

FIG. 5 illustrates a schematic diagram of a response and simulation flow of a four-stage gas emergency on a three-stage simulation system in accordance with an embodiment of the present application;

FIG. 6 (a) shows a configuration diagram of a simulation platform of a city gas multi-stage pipe network according to an embodiment of the present application; and

fig. 6 (b) shows a block diagram of a simulation platform of a city gas multi-stage pipe network according to an embodiment of the present application.

Detailed Description

In order to better understand the technical solutions of the present application, the following detailed description of the present application is provided with reference to the accompanying drawings and the specific embodiments. Embodiments of the present application will now be described in further detail with reference to the accompanying drawings and specific examples, but are not intended to be limiting of the present application.

The terms "first," "second," and the like, as used herein, do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. The word "comprising" or "comprises" and the like means that elements preceding the word encompass the elements recited after the word, and not exclude the possibility of also encompassing other elements. As used herein, "a or more" includes a and a number greater than a, and "B or less" as used herein includes not B but only a number less than B. The abbreviation "DN" in this application denotes the nominal diameter of the pipes of a gas network. "DN300", "DN50", "DN500" etc. correspond to gas network pipes of different diameter levels.

The order in which the steps of the methods described in the present application with reference to the accompanying drawings are performed is not intended to be limiting. As long as the logical relationship between the steps is not affected, several steps may be integrated into a single step, the single step may be decomposed into multiple steps, or the execution order of the steps may be exchanged according to specific requirements.

FIG. 1 shows a flow chart of a modeling simulation method of a multi-stage urban gas network according to an embodiment of the application. An example of a multi-stage network of urban fuel gas can be seen in fig. 2. As shown in fig. 2, the municipal gas multi-stage network may be divided into a municipal main network 201, a district network 202, and a management unit network 203. Specifically, municipal mains network 201 typically comprises network of different materials of DN500 and above and their associated ancillary structures, such as door stations (municipal gas distribution stations, gas storage stations), pressure regulating stations (high-medium pressure regulating stations), gas supply sources (such as coal gas plants, etc.), and typically provides high pressure. District network 202 typically includes networks of different materials for DNs 300-500 and their associated ancillary structures, such as voltage regulators/boxes (medium-low voltage regulators, etc.), shaft information, and typically provides medium voltage. The management unit network 203 typically comprises networks of different materials of DNs 50-300 and their associated ancillary structures such as voltage regulating stations/boxes, gates, end users (residential users), and the like.

As shown in fig. 1, the modeling simulation method of the urban gas multi-stage pipe network may include the following steps.

In step 100, a primary simulation system, a secondary simulation system and a tertiary simulation system with sequentially reduced operation authority are provided, so that the primary simulation system can acquire simulation data of the secondary simulation system and the tertiary simulation system.

In step 101, the user's operational rights are verified.

In case the user has a primary right (102 a), the following steps are performed with the primary simulation system. In step 103a, network data collected by the GIS system and the SCADA monitoring system on DN500 and above and related auxiliary structures is obtained, and accordingly, an urban trunk simulation model of the urban gas network is established. In step 104a, simulation analysis is performed on the urban trunk simulation model to obtain simulation data of each trunk node.

Taking urban main pipe network, step 103a and step 104a as examples, the data acquisition, modeling and simulation analysis solving of pipe networks of various levels will be described. Although the urban main pipe network is taken as an example, the data acquisition, modeling and simulation analysis solution can be also applied to the lower-level district pipe network and the management unit pipe network, and the details are not repeated later.

The SCADA monitoring system is also called as a monitoring and data acquisition system, is a production process control and scheduling automation system based on a computer, can monitor and control equipment running on site, and realizes various functions of data acquisition, measurement, various signal alarms, equipment control, parameter adjustment and the like. The SCADA system can monitor, manage and schedule the whole process of air intake, metering, transmission and distribution and pressure regulation of the urban gas pipe network, and realize automatic collection, classification, transmission, arrangement, analysis and storage of pipe network conditions. Specifically, the SCADA monitoring system may include a dispatch center, remote end stations (including a site control system and a monitoring point), and a communication system.

The dispatching center performs processing, display and warehousing of collected data and information integration with an urban gas network (such as a GIS system but not limited to the GIS system), and is generally composed of a SCADA server, an operator workstation, an engineer workstation, a communication processor and the like.

The remote terminal station can comprise various stations such as a gate station, each stage of voltage regulating station, CNG station, LNG station, industrial and commercial users, pipe network monitoring points, valve chambers and the like. The remote terminal station completes data collection of control equipment of the pipe network and the station yard, for example, a gas monitoring wireless data transmission unit (RTU) can be used for collecting pressure and flow information of each monitoring point of the pipe network, and the like.

The communication system can comprise a wired special line and a wireless CDMA/GPRS network, realizes large communication between each station control system and the monitoring point PLC/RTU and the dispatching center, ensures the real-time performance of data exchange of the SCADA system, and ensures timely, accurate, reliable, coordinated and high-efficiency work. Specifically, the temperature, pressure, flow and the like of a pipe network can be collected by the field instrument of each pipeline node, the RTU is responsible for collecting signals output by various field instruments in real time, then the collected data is uploaded to a dispatching center through a communication system, and the dispatching center can calculate and analyze the data and store the data in a shared database. For example, the network information, such as the city backbone network, monitored by the SCADA monitoring system, and the spatial data information from the city backbone network of the GIS system may be obtained by communicating with a dispatch center or database of the SCADA monitoring system and with a management center or database of the GIS system through a standard data interface OPC (process controlled object linking and embedding) or ODBC (open database interconnection).

Further, an urban trunk simulation model of the urban trunk pipe network can be established based on the acquired pipe network information of the GIS system and the SCADA monitoring system from the urban gas pipe network. The model integrates pipe network information of the GIS system and the SCADA monitoring system, establishes the model or provides similar algorithms in some commercial Gas pipeline system simulation software products, such as but not limited to SynerGEE Gas software, can synchronize or import data of the GIS system and the SCADA monitoring system, supports input modeling of map files with different formats, and can establish a multi-stage pressure system model of facilities including valves, pressure regulators, pipeline accessories and the like. In the application, the collected data of the GIS system and the SCADA monitoring system corresponding to the urban trunk pipe network are extracted, and the urban trunk simulation model of the urban trunk pipe network is built only according to the collected data. Similarly, collected data corresponding to the GIS system and SCADA monitoring system of the district network can be extracted, and a district simulation model of the district network can be built only according to the collected data. Similarly, collected data corresponding to the GIS and SCADA monitoring systems of the under-jurisdiction management units may be extracted and only management unit simulation models of the under-jurisdiction management units may be built accordingly.

Specifically, a user with primary authority may operate the primary simulation system, via which collected data corresponding to the GIS systems and SCADA monitoring systems of the respective levels of the municipal main pipe network, the jurisdiction, and the under-jurisdiction management unit can be acquired, but may only utilize collected data corresponding to the municipal main pipe network, since it is only necessary to take charge of construction of the municipal main simulation model, but may also freely acquire collected data of the GIS systems and SCADA monitoring systems of the respective levels of the jurisdiction pipe network, and the under-jurisdiction management unit pipe network, if necessary, for analysis. Further, a user with the second-level authority may operate the second-level simulation system, and acquire, via the second-level simulation system, acquired data of the GIS system and the SCADA monitoring system corresponding to the levels of the district pipe network and the management unit pipe network under the district, but may only use acquired data corresponding to the district pipe network, or may acquire, from the first-level simulation system, acquired data or simulation data of a small part of the urban trunk pipe network corresponding to the boundary condition for executing the pipe network simulation calculation. Further, a user with three-level authority can operate the three-level simulation system, acquire the acquired data of the GIS system and the SCADA monitoring system corresponding to the management unit pipe network and other levels through the three-level simulation system, and acquire the acquired data or simulation data of a small part of the district pipe network corresponding to the boundary conditions for executing pipe network simulation calculation from the two-level simulation system.

Taking the urban trunk network shown in fig. 2 as an example, how to simulate and calculate the pressure and flow of each trunk node will be described.

Based on the city main pipe network, initial conditions and boundary conditions (such as the air supply amount of the city gas distribution station) are input, and the initial conditions and boundary conditions comprise physical parameters of an air source point, flow and pressure of each node, information of all pipe sections and the like.

In the simulation process, a mathematical model equation is established as follows, and the flow and the pressure of each node in the pipe network are subjected to simulation calculation.

Equation of motion is defined using equation (1):

formula (1)

Wherein the first term on the left side of the equal sign is an inertia term and the second term is a convection term, W represents the flow rate of the fuel gas, ρ represents the density of the fuel gas, τ represents time, x represents the pipe position, d represents the inner diameter of the fuel gas pipe, α represents the inclination angle of the fuel gas pipe to the horizontal plane, radian represents, λ represents the hydraulic friction coefficient, p represents the gas pressure in the pipe, and g represents the gravitational acceleration.

The flow of the fuel gas in the pipeline complies with the law of conservation of mass, and the continuity equation reflects that the mass of the fuel gas flowing into a certain section of the pipeline section in unit time is equal to the mass of the fuel gas flowing out of the section of the pipeline section. Equation (2) can be used to define the unstable flow continuity equation for gas:

Formula (2)

For high pressure gas, also considering its compressibility, the equation of gas state can be defined using equation (3):

formula (3)

Where p represents pressure, Z represents gas compression factor, ρ represents gas density, R represents gas constant, and T represents absolute temperature.

The energy equation of the gas is defined by equation (4):

formula (4)

Wherein h represents specific enthalpy, M represents mass flow, A represents flow cross section of the pipeline, K represents heat transfer coefficient,

the soil temperature, T, the gas temperature, alpha, the inclination angle of the gas pipeline to the horizontal plane, radian, and the gravity acceleration are shown in a form.

The enthalpy equation of the gas is defined using equation (5):

formula (5)

The formulas (1) to (5) form 5 equations in total, wherein the equations contain 5 unknown variables ρ and M, P, T, h, and boundary conditions are set, so that the flow parameters of any one pipe section at any time in various levels of pipe networks such as an urban main pipe network can be solved, including but not limited to the flow, pressure, temperature and the like of fuel gas at each node.

Further, an accessory equation may be constructed for an accessory structure of a pipe network, such as an accessory structure of a municipal mains network. Taking the valve as an example, the pressure drop equation can be defined by equation (6):

Formula (6)

Wherein, the liquid crystal display device comprises a liquid crystal display device,

indicating the mass flow of gas at the beginning of the pipe, < + >>

The valve flow coefficient is represented by Z, the compression factor of the fuel gas is represented by Z, the specific gravity of the fuel gas relative to air is represented by father, T, the temperature of the fuel gas is represented by +.>

Representing the gas density at the beginning of the pipeline, +.>

And->

Representing the pressure at the beginning and the outlet of the pipe, respectively.

The equations of the auxiliary structures can be embedded into corresponding positions in the urban trunk simulation model of the urban trunk network, so that a transient model equation of the whole urban trunk network is formed, the central implicit difference is carried out on the transient model equation, then the Newton-Lafson method is used for carrying out iterative solution on a nonlinear equation set, and the iterative solution based on the transient model equation can be realized in various modes.

For example, the initial time pressure, temperature, and flow distribution may be determined and used as a calculation iteration initial value, and initial boundary conditions may be input according to a target region (e.g., a whole or partial region) to be calculated by simulation. And determining pipeline time step and space step, and dividing a numerical calculation grid. And in each time step, carrying out iterative solution on the nonlinear equation set until the difference value of each equation is smaller than the specified error. In each time step, a jacobian matrix can be calculated, a correction vector is solved, and each variable to be solved is calculated, so that equation difference values are calculated again. This solution process is clear and obvious to a person skilled in the art and is not described in detail here.

In case the user has secondary rights (102 b), the following steps are performed with the secondary simulation system. In step 103b, network data collected by the GIS system and the SCADA monitoring system for the district network of DN300-500 of the district and associated auxiliary structures are obtained, and a district simulation model of the urban gas network is built accordingly. In step 104b, simulation data of trunk nodes corresponding to boundary conditions of the district simulation model in the city trunk simulation model are obtained. In step 105b, simulation data of the corresponding trunk node is used as a boundary condition, and simulation analysis is performed on the district simulation model to obtain simulation data of each district node.

In case the user has three levels of rights (102 c), the following steps are performed with the three levels of simulation system. In step 103c, network data collected by the GIS system and the SCADA monitoring system on the management unit network of DN50-300 of the management unit under the jurisdiction and the associated auxiliary structures are obtained, and accordingly, a management unit simulation model of the urban gas network is established. In step 104c, simulation data of a district node corresponding to a boundary condition of the management unit simulation model in a district simulation model of the district to which the management unit belongs is obtained. In step 105c, simulation data of the corresponding jurisdiction nodes are used as boundary conditions, and simulation analysis is performed on the management unit simulation model to obtain simulation data of each management unit node.

By providing the primary simulation system, the secondary simulation system and the tertiary simulation system with sequentially reduced operation authorities, a small part of the simulation model of the superior simulation system collects data or simulation data to be used as boundary conditions of the simulation model of the present simulation system, the results of simulation analysis are shared step by step as required, and simultaneously the calculation load is also shared step by step, for example, a user with primary authorities uses the primary simulation system to simulate a large-sized urban trunk simulation model of an urban trunk network, a user with secondary authorities uses the secondary simulation system to simulate a medium-sized jurisdictional simulation model of a jurisdiction, and a user with tertiary authorities uses the tertiary simulation system to simulate a small-sized management unit simulation model of a management unit. Therefore, the method can perform nested hierarchical simulation and operation according to the hierarchical management architecture of the urban gas pipe network, can rapidly perform accurate simulation on the pipe network, and can rapidly diagnose the abnormal conditions of the pipe network and the auxiliary structures. Furthermore, the primary simulation system can acquire simulation data of the secondary simulation system and the tertiary simulation system, so that cross-level full utilization of pipe network simulation data of each level is facilitated, efficient overall regulation and control are performed on the pipe network, and the calculation cost is remarkably reduced.

In some embodiments, the primary authority is assigned to a dispatch center and/or lead cockpit of the gas group, the secondary authority is assigned to a regional branch and/or a head office of the gas group, and the tertiary authority is assigned to an operational management unit under the jurisdiction of the regional branch and/or the head office of the gas group. Therefore, the authority level arrangement is matched with the management level architecture of the gas group, the high-level simulation system can acquire simulation data of the low-level simulation system, the low-level simulation system can acquire small part of simulation data of the high-level simulation system according to simulation requirements, a manager of the high management level can acquire corresponding simulation data of each low management level as required so as to conduct global evaluation and control, the simulation data of the simulation model of the high management level are not completely sealed for the low management level, but a small part of simulation data required by simulation analysis of the simulation model corresponding to the low management level is provided appropriately, and cross-level efficient utilization, proper circulation and data safety of the simulation data are considered.

In some embodiments, the pressures in the network may be divided from low to high into low, medium, sub-high, high and ultra-high pressures such that the municipal main network, such as municipal main network 201 in fig. 2, carries at least one of the sub-high, high and ultra-high pressures such that the district network, such as district network 202 in fig. 2, carries at medium pressure such that the management unit network, such as management unit network 203 in fig. 2, carries at low pressure. Specifically, a simulation solution may be performed using a transient non-isothermal equation set, i.e., equations (1) - (6) above, to perform a simulation analysis on the urban trunk simulation model.

Meanwhile, a steady-state non-isothermal or isothermal equation set can be used for simulation solution to carry out simulation analysis on the district simulation model and the management unit simulation model. The steady state non-isothermal equation set includes the following equations (7) - (9), while the steady state isothermal equation set is simplified to equation (10).

At steady state, the flow parameters do not change with time, and the continuity equation is:

formula (7)

The equation of motion is:

formula (8)

The energy equation is:

formula (9)

The mass flow equation of the steady-state isothermal gas pipeline is as follows:

formula (10)

Wherein M is the mass flow of the pipeline,

for the starting pressure of the pipeline, +.>

Is the final pressure of the pipeline, d is the inner diameter of the pipeline, < ->

The hydraulic friction coefficient is that Z is the compression factor of natural gas under the condition of pipe transportation, F is the sectional area of a pipeline, R is a gas constant, T is the gas transportation temperature, and L is the length of a calculated pipe section. The same parameters in the formulas (7) - (10) as those in the formulas (1) - (6) have the same technical meanings, and are not described in detail herein.

Therefore, equations different from the district simulation model and the management unit simulation model are adopted for the city trunk simulation model, so that the simulation accuracy and the calculation load are considered. Specifically, the transient non-isothermal equation set with significantly larger calculation load is only used for calculation and analysis of the urban trunk simulation model, so that the generally more sufficient calculation resources of the primary simulation system are fully utilized, and more accurate calculation is performed on the higher pressure of the urban trunk pipe network and the operation parameters such as the pressure, the flow and the like with more significant dynamic change; meanwhile, the steady-state non-isothermal or isothermal equation set with remarkably reduced calculation load is only used for calculation analysis of the district simulation model and the management unit simulation model (for example, the steady-state non-isothermal equation set is applied to the former and the steady-state isothermal equation set is applied to the latter), so that the system is suitable for lower calculation resource configuration of a secondary simulation system and a tertiary simulation system compared with a primary simulation system, and the system is sufficient for calculating lower pressure and motion parameters such as generally stable pressure, flow and the like of a district pipe network and a management unit pipe network with robustness and accuracy.

FIG. 3 illustrates a flowchart of an example of obtaining simulation data of a trunk node in the urban trunk simulation model corresponding to boundary conditions of a jurisdictional simulation model, according to an embodiment of the application. As shown in fig. 3, the obtaining of the simulation data of the trunk node corresponding to the boundary condition of the district simulation model in the city trunk simulation model is further realized by the following steps. In the step 301 of the process of the present invention,

searching loops traversing all of the tubing in the jurisdictional simulation model. The jurisdiction of interest may be framed by the user via a mouse, such as for example, jurisdiction 401 in fig. 4. For jurisdiction 401, the loops of all of the conduits in the corresponding jurisdiction simulation model may be searched, i.e., whether all of the conduits in that jurisdiction 401 form a closed loop. In step 302, it is determined whether such a loop can be searched. If such a loop is not searched (no in step 302), such as in the case of district 401, where the pipeline 402 does not form a closed loop, then in step 303, a pipe segment having its end extended to a vicinity outside the district is searched for, for example, by a point capturing technique. Referring to fig. 4, a tube segment 403 can be searched with its end extending beyond the jurisdiction 401 in the vicinity. At step 304, loops are further searched through all of the tubing and protruding tubing segments in the jurisdictional simulation model. With reference to fig. 4, a closed circuit can be formed by connecting the protruding pipe section 403 and the pipe section 402 in the district 401, i.e. such a circuit can be searched. If such a loop is found (yes in step 305), then the end simulation data is also used as a boundary condition for the jurisdictional simulation model. Therefore, the full boundary conditions can be acquired for the district simulation model in a targeted manner so as to ensure smooth simulation calculation, and the data of the adjacent simulation model (of the extending pipe section) can be prevented from being excessively leaked to the district simulation model and users with lower authority.

Similarly, in some embodiments, simulation data of a jurisdictional node corresponding to a boundary condition of a jurisdictional simulation model of a jurisdiction to which the management unit belongs may be obtained by. A loop is searched through all of the pipes in the management unit simulation model. If such a loop is not searched, the search end extends to a pipe section in the vicinity outside the management unit. Further searching loops traversing all of the pipes and extending pipe segments in the management unit simulation model. If such a loop is searched, the simulation data of the end is also used as boundary conditions for the simulation model of the management unit.

The end of the extension tube segment 403 in fig. 4 may also be referred to as a transition point. For example, the area A and the area B are connected through a single pipeline, and if the pipe network condition of the area A is to be simulated, the information at the valve in the connecting pipe of the area A and the area B can be used for simplification to be used as a transition point. The transition point may be used as a boundary condition for the simulation model of zone a. In some embodiments, transition points may also exist between networks of different pressure levels, see FIG. 2, and high-medium voltage regulator stations 204 may be provided as transition points between municipal trunk network 201 and district network 202, such transition points between the municipal trunk simulation model and the district simulation model also being referred to as primary-secondary transition points. Similarly, the transition points between the jurisdictional simulation model and the management unit simulation model are referred to as secondary-tertiary transition points.

In some embodiments, the simulation method may further include the following steps associated with the transition point.

A first-second transition point between the city backbone simulation model and the jurisdiction simulation model may be determined, the first-second transition point being used to segment the city backbone simulation model and the jurisdiction simulation model, simulation data of the first-second transition point being used as boundary conditions of the jurisdiction simulation model.

A second-third level transition point between the jurisdiction simulation model and the management unit simulation model may be determined, the second-third level transition point being used to segment the jurisdiction simulation model and the management unit simulation model, simulation data of the second-third level transition point being used as boundary conditions of the management unit simulation model. Boundary conditions of the corresponding level simulation model can be obtained efficiently through determination of the transition points, and therefore accurate simulation analysis is achieved. Unlike the corresponding points of other boundary conditions, for example, the traffic and pressure of the end user (cell user) are also used as boundary conditions of the management unit simulation model, but the point at which they are located is not a transition point. The transition points have the function of dividing pipe networks of different levels.

Accordingly, in some embodiments, the simulation method further comprises: receiving interactive operation of a user for indicating folding and hiding a pipe network or unfolding the pipe network; under the condition that the interactive operation of the user indicating folding hidden pipe network is received and the user has primary authority, only an urban trunk simulation model at the upstream of the primary-secondary transition point is presented; and under the condition that the interactive operation of the folding hidden pipe network of the user is received and the user has the secondary authority, only presenting the jurisdictional simulation model upstream of the secondary-tertiary transition point.

In some embodiments, the simulation method further comprises: under the condition that the interactive operation of a user for indicating to expand a pipe network is received and the user has primary authority, enabling a primary simulation system to acquire simulation data of a secondary simulation system and a tertiary simulation system, and connecting and presenting the city trunk simulation model, the district simulation model and the management unit simulation model; under the condition that the interactive operation of the user for indicating to expand the pipe network is received and the user has the second-level authority, the second-level simulation system acquires the simulation data of the third-level simulation system, and the jurisdiction simulation model and the management unit simulation model are connected and presented together.

Therefore, a user can freely select to fold the hidden pipe network or unfold the pipe network according to the concerned region, so that the simulation result which simply presents the upstream city trunk simulation model or the district simulation model itself or the simulation result which comprehensively presents the city trunk simulation model or the low-level details which the district simulation model extends downwards can be selected according to the real-time requirement. Thus, taking the urban trunk simulation model as an example, a user with first-level authority, such as a dispatching center and/or a leading cockpit, can simply present the simulation result of the upstream urban trunk simulation model so as to initially locate the trunk fault region, and then expand and present the simulation data to check the district simulation model corresponding to the trunk fault region, so as to finely confirm the fault region in the district, thereby avoiding being submerged in a large amount of expanded detail simulation data at first, and further improving the analysis efficiency.

FIG. 5 illustrates a schematic diagram of a response and simulation flow of a four-stage gas emergency on a three-stage simulation system in accordance with an embodiment of the present application. As shown in fig. 5, the gas emergency class is classified into a particularly significant gas emergency, a general gas emergency, and a general gas emergency.

Specifically, the occurrence of one of the following events belongs to a particularly significant gas emergency: the problem of the upstream air supply system causes abnormal air supply in the whole market, so that the government starts an emergency supply plan; the emergency happens to the air supply system, so that more than 2 thousands of households stop supplying air; the gas composition in the urban gas source or gas supply system changes, so that the normal use of the end user equipment cannot be satisfied.

Further, one of the following events occurs as a major gas event: the abnormality of the air supply system causes the overpressure operation or air supply tension in the local area, and the alarm level of yellow or more specified by enterprises is reached; the pipe network operates in large-area overpressure, so that a large number of pipe networks or user facilities fail and leak air; the number of the gas stopping of resident users is more than 1 thousand of users and less than 2 thousand of users; continuously stopping the air for more than 24 hours in public canteens of higher institutions; the SCADA monitoring system cannot be recovered in a short period of paralysis, so that the operation of the air supply system cannot be monitored normally.

Further, one of the following conditions occurs, which belongs to a general gas emergency: the number of the gas stopping of resident users is more than 300 to less than 1 thousand; the heating period causes the gas interruption of a resident heating boiler or the gas interruption of a large-scale scattered heating user.

Further, the following conditions are common gas emergency events: the number of the gas stopping of resident users is below 300.

As shown in fig. 5, in the case of an emergency of ordinary gas, only the user with three-level authority (shown as the user with one star) is prompted, the three-level simulation system is called, and simulation analysis is performed on the management unit simulation model of the management unit pipe network where the event occurs, so as to guide maintenance and scheduling.

Under the condition of general gas emergency, prompting the user with three-level authority and the user with two-level authority (shown as the user with two stars), calling the two-level simulation system, and carrying out collaborative simulation analysis on the district simulation model of the district pipe network related to the event and the management unit simulation model related to the management unit pipe network so as to guide maintenance and scheduling.

Under the condition that a major gas event or a particularly major gas emergency occurs, prompting a user with first-level authority (shown as a user with three stars), a user with second-level authority and a user with third-level authority, and carrying out collaborative simulation analysis on the urban trunk simulation model, the district simulation model of a district pipe network related to the event and the management unit simulation model related to a management unit pipe network so as to guide maintenance and scheduling.

In this way, for each level of gas emergency, the highest level of responsibility people which need to give a guiding maintenance strategy to the event, such as a dispatching center and/or a leading cockpit of a gas group, an regional branch company and/or a head office of the gas group, or an operation management unit under the jurisdiction of the regional branch company and/or the head office of the gas group, can be automatically prompted, and except for calling a simulation model related to simulation data, the responsibility people corresponding to the highest level of the event can share the simulation data of the lower simulation model from the lower level of responsibility people, so that redundant interference to other irrelevant responsibility people is avoided, meanwhile, simulation data required for guiding the maintenance strategy is acquired pertinently, responsibility distribution for guiding the maintenance strategy is realized, and the responsibility distribution, comprehensive analysis and efficient rapid processing of various gas emergency events which occur in multiple levels among the multiple layers of responsibility people of the gas group are facilitated.

Fig. 6 (a) shows a configuration diagram of a simulation platform of a multi-stage urban gas network according to an embodiment of the present application. As shown in FIG. 6 (a), the simulation platform 600 may include a primary simulation system 600a, a secondary simulation system 600b, a tertiary simulation system 600, and a shared database 600d. The shared database 600d may be distributed in the cloud or may be fixed in a remote location. The primary simulation system 600a is embedded with an urban backbone simulation model for call, the secondary simulation system 600b is embedded with a jurisdictional simulation model 600b for call, and the tertiary simulation system 600c is embedded with a management unit simulation model 600c for call. Simulation data for each simulation model may be stored in the shared database 600d, and each of the primary simulation system 600a, the secondary simulation system 600b, and the tertiary simulation system 600 may be provided with an interface (not shown) to transmit to the shared database 600d and/or acquire data from the shared database 600d that it has authority to acquire. For example, the primary simulation system 600a has access to all data, while the secondary and

tertiary simulation systems

600b, 600b can only acquire data of their own modeling simulation and simulation data across other systems required for its modeling simulation. By letting the shared database 600d take charge of the data sharing according to the rights, the communication and workload of each advanced system such as the primary simulation system 600a (which also receives the network information from the GIS system and the SCADA monitoring system of the urban gas network) can be significantly reduced, so that the simulation analysis work is focused more.

Fig. 6 (b) shows a block diagram of a simulation platform of a city gas multi-stage pipe network according to an embodiment of the present application. As shown in figure 6 (b) of the drawings,

the simulation platform 600 may include an interface 601 and at least one processor 602. The interface 601 may be configured to: and receiving pipe network information of a GIS system and a SCADA monitoring system from the urban gas multi-stage pipe network. The processor 602 may be configured to perform a simulation method of a city gas multi-stage pipe network in accordance with various embodiments of the present application. For example, the simulation platform 600 may be implemented on a fixed server or may be implemented on a cloud, which is not described herein.

In some embodiments, the present application further provides a computer-readable medium having stored thereon computer-executable instructions that, when executed by a processor, implement a simulation method for a multi-stage network of urban gas according to various embodiments of the present application. The method may include the following steps. The first-stage simulation system, the second-stage simulation system and the third-stage simulation system with sequentially reduced operation authority are provided, so that the first-stage simulation system can acquire simulation data of the second-stage simulation system and the third-stage simulation system. The user's operational rights are verified. Under the condition that a user has primary authority, the primary simulation system is utilized to acquire pipe network data acquired by a GIS system and an SCADA monitoring system for DN500 and above urban trunk pipe networks and associated auxiliary structures, and accordingly, an urban trunk simulation model of the urban gas pipe network is established. And performing simulation analysis on the urban trunk simulation model to obtain simulation data of each trunk node. Under the condition that the user has the second-level authority, the second-level simulation system is utilized to acquire pipe network data acquired by the GIS system and the SCADA monitoring system for the jurisdictional pipe network of DN300-500 of the jurisdiction and associated auxiliary structures, and accordingly, a jurisdictional simulation model of the urban gas pipe network is established. And acquiring simulation data of trunk nodes corresponding to boundary conditions of the district simulation model in the city trunk simulation model. And carrying out simulation analysis on the district simulation model by using the simulation data of the corresponding trunk nodes as boundary conditions so as to obtain the simulation data of each district node. Under the condition that a user has three-level authority, the three-level simulation system is utilized to acquire pipe network data acquired by the GIS system and the SCADA monitoring system for the management unit pipe network of DN50-300 of the management unit under the jurisdiction and associated auxiliary structures, and accordingly, a management unit simulation model of the urban gas pipe network is established. And obtaining simulation data of district nodes corresponding to boundary conditions of the management unit simulation model in the district simulation model of the district to which the management unit belongs. And carrying out simulation analysis on the management unit simulation model by using the simulation data of the corresponding district node as a boundary condition so as to obtain the simulation data of each management unit node.

Examples of modeling simulation methods of other embodiments throughout this application may be incorporated herein and are not described in detail herein.

In some embodiments, the processor 602 may be, for example, a processing component including one or more general-purpose processors, such as a microprocessor, a Central Processing Unit (CPU), a Graphics Processing Unit (GPU), or the like.

The computer-readable storage medium described above is non-transitory and may be, for example, read-only memory (ROM), random-access memory (RAM), phase-change random-access memory (PRAM), static random-access memory (SRAM), dynamic random-access memory (DRAM), electrically erasable programmable read-only memory (EEPROM), other types of random-access memory (RAMs), flash memory or other forms of flash memory, cache, registers, static memory, compact disc read-only memory (CD-ROM), digital Versatile Discs (DVD) or other optical storage, magnetic tape or other magnetic storage devices, or any other non-transitory medium that may be used to store information or instructions that may be accessed by a computer device.

The various processing steps in this application may be written in various programming languages, such as, but not limited to, fortran, c++, and Java, and are not described in detail herein.

Furthermore, although exemplary embodiments have been described herein, the scope thereof includes any and all embodiments having equivalent elements, modifications, omissions, combinations (e.g., of the various embodiments across), adaptations or alterations as pertains to the present application. Elements in the claims are to be construed broadly based on the language employed in the claims and are not limited to examples described in the present specification or during the practice of the present application, which examples are to be construed as non-exclusive. It is intended, therefore, that the specification and examples be considered as exemplary only, with a true scope and spirit being indicated by the following claims and their full scope of equivalents.

The above description is intended to be illustrative and not restrictive. For example, the above-described examples (or one or more aspects thereof) may be used in combination with each other. For example, other embodiments may be used by those of ordinary skill in the art upon reading the above description. In addition, in the above detailed description, various features may be grouped together to streamline the application. This is not to be interpreted as an intention that the disclosed features not being claimed are essential to any claim. Rather, the subject matter of the present application is capable of less than all of the features of a particular disclosed embodiment. Thus, the following claims are hereby incorporated into the detailed description as examples or embodiments, with each claim standing on its own as a separate embodiment, and it is contemplated that these embodiments may be combined with one another in various combinations or permutations. The scope of the invention should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.

The above embodiments are only exemplary embodiments of the present application and are not intended to limit the present invention, the scope of which is defined by the claims. Various modifications and equivalent arrangements may be made to the present invention by those skilled in the art, which modifications and equivalents are also considered to be within the scope of the present invention.

Claims

1. The simulation method of the urban gas multi-stage pipe network is characterized by comprising the following steps of:

providing a primary simulation system, a secondary simulation system and a tertiary simulation system with sequentially reduced operation authority, so that the primary simulation system can acquire simulation data of the secondary simulation system and the tertiary simulation system;

verifying an operation right of a user;

in the case that the user has a primary authority, with the primary simulation system,

acquiring pipe network data acquired by a GIS system and an SCADA monitoring system for DN500 and above and related auxiliary structures, and accordingly establishing an urban trunk simulation model of the urban gas pipe network;

performing simulation analysis on the urban trunk simulation model to obtain simulation data of each trunk node;

in case the user has secondary rights, with the secondary simulation system,

Acquiring pipe network data acquired by a GIS system and an SCADA monitoring system for a district pipe network of DN300-500 of a district and associated auxiliary structures, and establishing a district simulation model of the urban gas pipe network according to the pipe network data;

obtaining simulation data of a trunk node corresponding to boundary conditions of a district simulation model in the city trunk simulation model, and performing simulation analysis on the district simulation model by using the simulation data of the trunk node as the boundary conditions to obtain the simulation data of each district node, wherein the simulation data comprises the following specific steps:

selecting a district of interest from the user frame, and searching loops traversing all pipelines in a district simulation model of the district of interest;

if a non-closed loop is searched, searching a pipe section of which the tail end extends to an adjacent area outside the district of interest through a point capturing technology, and taking the tail end as a transition point for dividing the urban trunk simulation model and the district simulation model;

searching loops traversing all pipelines and extending pipe sections in the district simulation model, and if such loops are searched, combining trunk nodes corresponding to boundary conditions of the district simulation model in the divided trunk simulation model with simulation data of the transition points as simulation boundary conditions to perform simulation calculation;

In the case of a user having three levels of rights, with the three levels of simulation system,

acquiring pipe network data acquired by a GIS system and an SCADA monitoring system for a management unit pipe network of DN50-300 of a management unit under a jurisdiction and associated auxiliary structures, and accordingly establishing a management unit simulation model of the urban gas pipe network;

obtaining simulation data of district nodes corresponding to boundary conditions of a district simulation model of a district to which the management unit belongs;

and carrying out simulation analysis on the management unit simulation model by using the simulation data of the corresponding district node as a boundary condition so as to obtain the simulation data of each management unit node.

2. The simulation method according to claim 1, further comprising:

the primary authority is given to a dispatching center and/or a leading cockpit of the gas group, the secondary authority is given to regional branch companies and/or head companies of the gas group, and the tertiary authority is given to operation management units under the jurisdiction of the regional branch companies and/or the head companies of the gas group.

3. The simulation method according to claim 1, further comprising:

dividing the pressure in the pipe network into low pressure, medium pressure, secondary high pressure, high pressure and ultrahigh pressure from low to high, so that the pressure borne by the urban main pipe network is at least one of the secondary high pressure, the high pressure and the ultrahigh pressure, the pressure borne by the pipe network in the district is the medium pressure, and the pressure borne by the pipe network of the management unit is the low pressure;

Using a transient non-isothermal equation set to carry out simulation solution to carry out simulation analysis on the urban trunk simulation model;

and performing simulation solution by using a steady-state non-isothermal or isothermal equation set to perform simulation analysis on the district simulation model and the management unit simulation model.

4. The simulation method according to claim 1, further comprising:

the gas emergency class is divided into a special major gas emergency, a general gas emergency and a general gas emergency,

wherein, one of the following conditions occurs belongs to a particularly serious gas emergency: the problem of the upstream air supply system causes abnormal air supply in the whole market, so that the government starts an emergency supply plan; the emergency happens to the air supply system, so that more than 2 thousands of households stop supplying air; the change of the gas composition in the urban gas source or gas supply system can not meet the normal use of the terminal user equipment,

one of the following events occurs as a major gas event: the abnormality of the air supply system causes the overpressure operation or air supply tension in the local area, and the alarm level of yellow or more specified by enterprises is reached; the pipe network operates in large-area overpressure, so that a large number of pipe networks or user facilities fail and leak air; the number of the gas stopping of resident users is more than 1 thousand of users and less than 2 thousand of users; continuously stopping the air for more than 24 hours in public canteens of higher institutions; the SCADA monitoring system cannot be recovered in a short period of paralysis, so that the operation of the air supply system cannot be monitored normally,

One of the following conditions occurs, which belongs to a general gas emergency: the number of the gas stopping of resident users is more than 300 to less than 1 thousand; the heating period causes the gas interruption of a resident heating boiler or the gas interruption of a large-scale scattered heating user,

the following conditions are common gas emergency events: the number of the gas stopping of resident users is below 300 users;

under the condition of common gas emergency, only prompting users with three-level authority, and carrying out simulation analysis on a management unit simulation model of a management unit pipe network where the event occurs so as to guide maintenance and scheduling;

under the condition of a general gas emergency, prompting a user with three-level authority and a user with two-level authority, and carrying out collaborative simulation analysis on a district simulation model of a district pipe network related to the event and a management unit simulation model related to a management unit pipe network so as to guide maintenance and scheduling;

under the condition that a major gas event or a particularly major gas emergency occurs, prompting a user with first-level authority, a user with second-level authority and a user with third-level authority, and carrying out collaborative simulation analysis on the urban trunk simulation model, the district simulation model of the district pipe network related to the event and the management unit simulation model related to the management unit pipe network so as to guide maintenance and scheduling.

5. The simulation method according to claim 1, further comprising: the obtaining simulation data of the district node corresponding to the boundary condition of the management unit simulation model in the district simulation model of the district to which the management unit belongs further comprises:

searching loops traversing all pipelines in the management unit simulation model; if such a loop is not searched, a pipe section with the searching end extending to an area adjacent to the outside of the management unit is searched; further searching loops traversing all of the pipes and the extended pipe sections in the management unit simulation model, and if such loops are searched, using the end simulation data as boundary conditions of the management unit simulation model.

6. The simulation method according to claim 1, further comprising:

determining a first-second transition point between the city backbone simulation model and the jurisdiction simulation model, wherein the first-second transition point is used for dividing the city backbone simulation model and the jurisdiction simulation model;

determining a secondary-tertiary transition point between the jurisdictional simulation model and the management unit simulation model, the secondary-tertiary transition point being used to segment the jurisdictional simulation model and the management unit simulation model,

The simulation data of the first-level-second-level transition points are used as boundary conditions of the district simulation model, and the simulation data of the second-level-third-level transition points are used as boundary conditions of the management unit simulation model.

7. The simulation method according to claim 6, further comprising:

receiving interactive operation of a user for indicating folding and hiding a pipe network or unfolding the pipe network;

under the condition that the interactive operation of the user indicating folding hidden pipe network is received and the user has primary authority, only an urban trunk simulation model at the upstream of the primary-secondary transition point is presented;

and under the condition that the interactive operation of the folding hidden pipe network of the user is received and the user has the secondary authority, only presenting the jurisdictional simulation model upstream of the secondary-tertiary transition point.

8. The simulation method according to claim 6, further comprising:

under the condition that the interactive operation of a user for indicating to expand a pipe network is received and the user has primary authority, enabling a primary simulation system to acquire simulation data of a secondary simulation system and a tertiary simulation system, and connecting and presenting the city trunk simulation model, the district simulation model and the management unit simulation model;

Under the condition that the interactive operation of the user for indicating to expand the pipe network is received and the user has the second-level authority, the second-level simulation system acquires the simulation data of the third-level simulation system, and the jurisdiction simulation model and the management unit simulation model are connected and presented together.

9. A simulation system for a multi-stage pipe network of urban fuel gas, comprising:

an interface configured to: receiving pipe network information of a GIS system and an SCADA monitoring system from a multi-stage pipe network of the urban gas;

at least one processor configured to: simulation method of the urban gas multi-stage pipe network according to any one of claims 1-8.

10. A computer readable medium having stored thereon computer executable instructions which, when executed by a processor, implement a method of simulating a multi-stage pipe network for urban gas according to any one of claims 1-8.