CN115879324A

CN115879324A - Simulation method, simulation platform and medium for urban gas multistage pipe network

Info

Publication number: CN115879324A
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: 2023-03-31
Anticipated expiration: 2043-02-15
Also published as: CN115879324B

Abstract

The application relates to a simulation method, a simulation platform and a medium for an urban gas multistage pipe network. And providing a one-level to three-level system with sequentially reduced operation authority. And verifying the user operation right item. And for the primary authority, establishing a city backbone model by using a primary system, and carrying out simulation analysis to obtain simulation data of each backbone node. For the secondary authority, establishing a district model by using a secondary system; and acquiring simulation data of corresponding trunk nodes in the city 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 three-level authority, a management unit model is established by using a three-level system; and acquiring simulation data of corresponding district nodes 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 nodes. Therefore, nested hierarchical simulation and operation can be performed according to the hierarchical management architecture of the urban gas pipe network, data of all levels of pipe networks are fully utilized in a cross-level mode, overall regulation and control are efficient, and calculation cost is reduced remarkably.

Description

Simulation method, simulation platform and medium for urban gas multistage pipe network

Technical Field

The application relates to a modeling simulation method, a modeling simulation system and a medium for an urban public facility pipe network, in particular 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 complex and 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 established for an urban gas pipe network so as to uniformly manage information such as pipe networks, valves, gate shafts, construction times, materials and the like. Although the gas enterprises begin to uniformly purchase simulation software, simulation analysis is usually performed on main trunk pipes and main loops of cities.

The pressure level of the large-scale urban pipe network is complex, and the large-scale urban pipe network is conveyed to a terminal user through a gate station, a pipe network, a gas storage facility, a pressure regulating station box, a gate well, a management facility and a monitoring system in the multi-level pipe network. If integrated calculation is carried out on a pipe network system of a branch from a trunk to a cell level in a large city, the number of calculation nodes is very large, data of a monitoring system is complicated, a large amount of data needs to be processed behind a simulation interactive interface, the integrated calculation load is large, the simulation speed is slow, and the requirements on hardware and calculation power of a processor are extremely high.

Although management units in some jurisdictions in cities can purchase some gas pipe network management software, the simulation platform of the main pipe network is split, is limited by local computing 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 for the urban gas multi-stage pipe network can perform nested hierarchical simulation and operation according to a hierarchical management framework of the urban gas pipe network, can quickly perform accurate simulation on the pipe network, quickly diagnose the abnormal conditions of the pipe network and an attached structure, are beneficial to fully utilizing simulation data of the pipe network at all levels in a cross-level mode, perform efficient overall regulation and control on the pipe network, and remarkably reduce calculation cost.

According to a first scheme of the application, a simulation method of an urban gas multistage pipe network is provided. The simulation method comprises the following steps. The first-level simulation system, the second-level simulation system and the third-level simulation system with sequentially reduced operation authority are provided, so that the first-level simulation system can obtain simulation data of the second-level simulation system and the third-level simulation system. And verifying the operation right of the user. Under the condition that a user has primary authority, acquiring pipe network data acquired by a GIS system and an SCADA monitoring system for a DN500 and above urban trunk pipe networks and associated affiliated structures by utilizing the primary simulation system, and accordingly establishing an urban trunk simulation model of the urban gas pipe network. And carrying out simulation analysis on the city trunk simulation model to obtain simulation data of each trunk node.

And under the condition that the user has secondary authority, acquiring the pipe network data acquired by the GIS system and the SCADA monitoring system for the DN300-500 district pipe network of the district and the associated accessory structures by using the secondary simulation system, and establishing a district simulation model of the urban gas pipe network according to the pipe network data. And acquiring simulation data of the trunk nodes corresponding to the boundary conditions of the district simulation model in the city trunk simulation model. And performing simulation analysis on the jurisdiction simulation model by using the simulation data of the corresponding trunk node as a boundary condition to obtain the simulation data of each jurisdiction node. And under the condition that the user has three-level authority, acquiring pipe network data acquired by a GIS system and an SCADA monitoring system for DN50-300 management unit pipe networks of management units in the jurisdictions and associated auxiliary structures by utilizing the three-level simulation system, and establishing a management unit simulation model of the urban gas pipe network according to the pipe network data. And acquiring 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. And performing simulation analysis on the management unit simulation model by using the simulation data of the corresponding jurisdictional node as a boundary condition to obtain the simulation data of each management unit node.

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

According to the simulation method, the simulation platform and the medium for the urban gas multi-stage pipe network, which are provided by the embodiments of the application, the operation authority is sequentially reduced for the first-stage simulation system, the second-stage simulation system and the third-stage simulation system, the related simulation data of the simulation model of the upper-stage simulation system is used as the boundary condition of the simulation model of the current-stage simulation system, the simulation analysis result is transferred and shared step by step as required, and the calculation load is also transferred step by step, so that nested hierarchical simulation and operation can be performed according to the hierarchical management framework of the urban gas pipe network, the accurate simulation can be rapidly performed on the pipe network, the abnormal conditions of the pipe network and the accessory structure can be rapidly diagnosed, the simulation data of the second-stage simulation system and the third-stage simulation system can be obtained by the first-stage simulation system, the cross-stage full utilization of the simulation data of the pipe network at each stage is facilitated, the efficient overall regulation and control of the pipe network is performed, and the calculation cost is remarkably reduced.

Drawings

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

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

FIG. 2 shows a hierarchical schematic of a city gas multi-stage pipe network according to an embodiment of the application;

FIG. 3 is a flowchart illustrating an example of obtaining simulation data of a trunk node corresponding to a boundary condition of a district simulation model in the city trunk simulation model according to 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 shows an overview of the response of a four-stage gas emergency on a three-stage simulation system and a simulation flow according to an embodiment of the 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 the city gas multi-stage pipe network according to the embodiment of the application.

Detailed Description

In order to make the technical solutions of the present application better understood, the present application is described in detail below with reference to the accompanying drawings and the detailed description. The embodiments of the present application will be described in further detail below with reference to the drawings and specific embodiments, but the present application is not limited thereto.

As used in this application, the terms "first," "second," and the like 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 the element preceding the word comprises the element listed after the word, and does not exclude the possibility that other elements may also be included. The term "a or more" used in the present application includes a and a number greater than a, and the term "B or less" used does not include B but includes only a number smaller than B. The abbreviation "DN" in this application denotes the nominal diameter of the pipes of the gas network. "DN300", "DN50", "DN500", etc. correspond to gas pipe network pipes of different diameter levels.

The order of execution of the steps in the methods described in this application in connection with the figures is not intended to be limiting. As long as the logical relationship between the steps is not affected, the steps can be integrated into a single step, the single step can be divided into a plurality of steps, and the execution order of the steps can be changed according to the specific requirements.

Fig. 1 shows a flowchart of a modeling simulation method of a city gas multi-stage pipe network according to an embodiment of the application. An example of a city gas multi-stage pipe network can be seen in fig. 2. As shown in fig. 2, the urban gas multi-stage pipe network can be divided into an urban main pipe network 201, a district pipe network 202 and a management unit pipe network 203. Specifically, the main city pipe network 201 generally includes pipe networks of different materials of DN500 and above and their associated auxiliary structures, such as gate stations (city gas distribution stations, gas storage stations), pressure regulating stations (high-medium pressure regulating stations), gas supply sources (such as coal gas plants, etc.), etc., and generally provides high pressure. The jurisdictional network 202 typically contains a network of different materials of DN300-500 and its associated ancillary structures such as surge stations/boxes (medium-low pressure surge stations, etc.), lock well information, and typically provides medium pressure. The management unit pipe network 203 typically comprises a network of different materials of DN50-300 and their associated ancillary structures such as pressure regulating stations/boxes, gates, end users (residential users), etc.

As shown in fig. 1, the modeling simulation method for the city 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 permissions are provided, so that the primary simulation system can obtain simulation data of the secondary simulation system and the tertiary simulation system.

In step 101, the operation right of the user is verified.

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

Taking city main pipe network, step 103a and step 104a as examples, the following describes data acquisition, modeling and simulation analysis solving of various levels of pipe networks. Although the city main pipe network is taken as an example, the data acquisition, modeling and simulation analysis solving can also be suitable for a lower-level district pipe network and a management unit pipe network, and are not described in detail later.

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

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

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

The communication system can comprise a wired special line and a wireless CDMA/GPRS network, realizes the large communication between each station control system and the PLC/RTU of the monitoring point and the dispatching center, ensures the real-time performance of the data exchange of the SCADA system, and ensures the SCADA system to work in time, accurately, reliably, coordinately and efficiently. Specifically, the field instruments of each pipeline node can be used for collecting the temperature, the pressure, the flow and the like of a pipe network, the RTU is responsible for collecting signals output by various field instruments in real time, then the collected data are uploaded to the dispatching center through the communication system, and the dispatching center can calculate and analyze the data and store the data in the shared database. For example, the network information such as the city main network monitored by the SCADA monitoring system and the spatial data information from the city main network of the GIS system can be obtained by communicating with a scheduling center or a database of the SCADA monitoring system through a standard data interface OPC (process control 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 from the GIS system and the SCADA monitoring system of the urban gas pipe network. The model integrates and processes pipe network information of a GIS system and an SCADA monitoring system, establishes the model or provides similar algorithms in some commercially available Gas pipeline system simulation software products, such as but not limited to SynergE 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 method, the collected data of the GIS system and the SCADA monitoring system corresponding to the urban main pipe network are extracted, and the urban main pipe simulation model of the urban main pipe network is established only according to the collected data. Similarly, the collected data of the GIS system and the SCADA monitoring system corresponding to the district pipe network can be extracted, and a district simulation model of the district pipe network is established according to the collected data. Similarly, the collected data of the GIS system and SCADA monitoring system corresponding to the management unit under jurisdiction may be extracted, and the management unit simulation model of the management unit under jurisdiction may be established based on this.

Specifically, a user with a primary authority can operate the primary simulation system, and can acquire the acquired data of the GIS system and the SCADA monitoring system corresponding to each level of the city main pipe network, the jurisdiction and the management unit under the jurisdiction via the primary simulation system, but can only utilize the acquired data corresponding to the city main pipe network, because the primary simulation system is only responsible for the construction of the city main pipe network simulation model, but can freely acquire the acquired data of the GIS system and the SCADA monitoring system of each level of the jurisdiction pipe network and the management unit under the jurisdiction for analysis if needed. Further, a user with a secondary authority can operate the secondary simulation system, and can obtain the collected data of the GIS system and the SCADA monitoring system corresponding to the levels of the administrative region pipe network, the administrative region management unit pipe network and the like through the secondary simulation system, but can only use the collected data corresponding to the administrative region pipe network, and can also obtain the collected data or the simulation data of a small part of the city main pipe network corresponding to the boundary condition for executing pipe network simulation calculation from the primary simulation system. Further, a user with a third level of authority can operate the third level simulation system, and can obtain data collected by the GIS system and the SCADA monitoring system corresponding to the management unit pipe network and other levels through the third level simulation system, and also can obtain data collected or simulated data of a small part of district pipe network corresponding to boundary conditions for executing pipe network simulation calculation from the second level simulation system.

The following describes how to calculate the pressure and flow of each trunk node by simulation, taking the city main pipe network shown in fig. 2 as an example.

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

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.

Using equation (1), the equation of motion is defined:

formula (1)

Where the first term to the left of the equality sign is the inertial term and the second term is the convective term, W represents the flow rate of the gas, ρ represents the density of the gas, τ represents time, x represents the location of the pipe, d represents the internal diameter of the gas pipe, α represents the angle of inclination of the gas pipe to the horizontal, expressed in radians, λ represents the coefficient of hydraulic friction, p represents the gas pressure in the pipe, and p represents the acceleration of gravity.

The flow of the fuel gas in the pipeline follows the mass conservation law, 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. The unstable flow continuity equation of the gas can be defined using equation (2):

formula (2)

For high pressure gas, the compressibility of the gas is also considered, and the gas state equation can be defined by the formula (3):

formula (3)

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

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

formula (4)

Wherein h represents specific enthalpy, M represents mass flow, A represents flow cross-sectional area of the pipe, K represents heat transfer coefficient,

represents the soil temperature, T represents the gas temperature, α represents the angle of inclination of the gas duct to the horizontal, in radians, and represents the acceleration of gravity.

The enthalpy equation for gas is defined using equation (5):

formula (5)

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

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

formula (6)

Wherein,

represents the mass flow of the gas at the beginning of the pipeline and is greater or less than>

Represents the flow coefficient of the valve, Z represents the compression factor of the gas, T represents the specific gravity of the gas relative to the air, and T represents the temperature of the gas, and>

represents the gas density at the starting point of the pipeline and is used for judging whether the gas density is greater or less>

And &>

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

Equations of all auxiliary structures can be embedded into corresponding positions in an urban trunk simulation model of the urban trunk pipe network, so that a transient model equation of the whole urban trunk pipe network is formed, central implicit difference is carried out on the transient model equation, then a non-linear equation set is iteratively solved by a Newton-Raphson method, and the iterative solution based on the transient model equation can be realized in various modes.

For example, the pressure, temperature and flow distributions at the initial time may be determined as initial values of the calculation iteration and the initial boundary conditions may be input according to the target region (e.g., whole or local region) to be simulated and calculated. Determining the time step length and the space step length of the pipeline, and dividing the number to calculate the grid. And in each time step, carrying out iterative solution on the nonlinear equation set until the difference value of each equation is less than a specified error. Within each time step, a Jacobian matrix can be calculated, correction vectors are solved, variables to be solved are calculated, and equation difference values are calculated. This solving process is clear to those skilled in the art and will not be described in detail here.

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

In the case where the user has three levels of permissions (102 c), the following steps are performed using the three-level simulation system. In step 103c, acquiring pipe network data acquired by the management unit pipe network of DN50-300 of the management units in the administrative area and associated auxiliary structures by the GIS system and the SCADA monitoring system, and accordingly establishing a management unit simulation model of the urban gas pipe network. In step 104c, acquiring the 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. In step 105c, simulation analysis is performed on the management unit simulation model by using the simulation data of the corresponding jurisdictional node as a boundary condition to obtain the simulation data of each management unit node.

By providing a primary simulation system, a secondary simulation system and a tertiary simulation system with sequentially reduced operation permissions, a small part of collected data or simulation data of a simulation model of the primary simulation system is used as a boundary condition of a simulation model of the primary simulation system, a simulation analysis result is transferred and shared step by step as required, and a calculation load is also transferred step by step, for example, a user with the primary permission utilizes the primary simulation system to simulate a large city main trunk simulation model of a city main pipe network, a user with the secondary permission utilizes the secondary simulation system to simulate a medium-sized district simulation model of a district, and a user with the tertiary permission utilizes the tertiary simulation system to simulate a small management unit simulation model of a management unit. Therefore, nested hierarchical simulation and operation can be performed according to the hierarchical management structure of the urban gas pipe network, accurate simulation can be performed on the pipe network quickly, and abnormal conditions of the pipe network and the attached structures can be diagnosed quickly. Furthermore, the first-level simulation system can acquire the simulation data of the second-level simulation system and the third-level simulation system, cross-level full utilization of the simulation data of all levels of the pipe network is facilitated, efficient overall regulation and control of the pipe network are performed, and the calculation cost is remarkably reduced.

In some embodiments, the primary right is assigned to a dispatching center and/or a leading cockpit of the gas group, the secondary right is assigned to a regional branch company and/or a head office of the gas group, and the tertiary right is assigned to an operation management unit under the jurisdiction of the regional branch company 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 the simulation data of the low-level simulation system, the low-level simulation system can acquire a small part of the simulation data of the high-level simulation system according to the simulation requirement, a manager of the high-level management level can acquire the corresponding simulation data of each low-level management level according to the requirement so as to perform global evaluation and regulation, the simulation data of the simulation model of the high-level management level is not completely closed to the low-level management level, but a small part of the simulation model corresponding to the low-level management level is provided properly for simulation analysis, and cross-level efficient utilization, proper circulation and data safety of the simulation data are considered.

In some embodiments, the pressure in the pipe network may be divided into low pressure, medium pressure, secondary high pressure, and extra high pressure from low to high, so that the city main pipe network, for example, the city main pipe network 201 in fig. 2, bears at least one of the secondary high pressure, the high pressure, and the extra high pressure, so that the jurisdiction pipe network, for example, the jurisdiction pipe network 202 in fig. 2, bears the pressure of the medium pressure, so that the management unit pipe network, for example, the management unit pipe network 203 in fig. 2, bears the pressure of the low pressure. Specifically, the simulation analysis of the city trunk simulation model can be performed by using the transient non-isothermal equations, i.e., the above equations (1) to (6) to perform the simulation solution.

Meanwhile, a steady-state non-isothermal or isothermal equation set can be used for simulation solution to perform simulation analysis on the district simulation model and the management unit simulation model. The steady-state non-isothermal equations include the following equations (7) to (9), and the steady-state isothermal equations are 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 transmission pipeline is as follows:

formula (10)

Where M is the mass flow rate of the pipeline,

is the starting pressure of the duct>

Is the end pressure of the pipeline, d is the internal diameter of the pipeline,/>

the coefficient of hydraulic friction resistance, Z is the compression factor of natural gas under the pipe conveying condition, F is the sectional area of the pipeline, R is the gas constant, T is the gas conveying temperature, and L is the length of the calculated pipe section. The same parameters in formula (7) to formula (10) as in formula (1) to formula (6) have the same technical meaning, and are not described herein.

Therefore, an equation different from the district simulation model and the management unit simulation model is adopted for the city main simulation model, so that the simulation accuracy and the calculation load are both considered. Specifically, the transient non-isothermal equation set with significantly larger computational load is only used for computational analysis of the urban trunk simulation model, so that the generally more sufficient computational resources of the primary simulation system are fully utilized, and more accurate computation is performed on operating parameters such as higher pressure and more significantly dynamically changed pressure, flow and the like of the urban trunk network; meanwhile, the steady-state non-isothermal or isothermal equation set with significantly reduced computational load is only used for computational analysis of the jurisdictional simulation model and the management unit simulation model (for example, the former applies the steady-state non-isothermal equation set and the latter applies the steady-state isothermal equation set) so as to adapt to lower computational resource configuration of the second-level simulation system and the third-level simulation system compared with the first-level simulation system, and to be robust and accurate enough to compute the lower pressure and the generally stable pressure, flow and other motion parameters of the jurisdictional pipe network and the management unit pipe network.

Fig. 3 is a flowchart illustrating an example of acquiring simulation data of a trunk node corresponding to a boundary condition of a district simulation model in the city trunk simulation model according to an embodiment of the present application. As shown in fig. 3, obtaining 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 a step 301 of the method, the step of,

and searching and traversing loops of all pipelines in the district simulation model. The jurisdiction of interest can be framed by a user via a mouse, such as the jurisdiction 401 in FIG. 4. For the jurisdiction 401, it is possible to search for loops of all pipelines in the corresponding jurisdiction simulation model, that is, whether all pipelines in the jurisdiction 401 form a closed loop. At step 302, it is determined whether such a loop can be searched. If no such circuit is searched (no in step 302), such as in the case of jurisdiction 401, where lines 402 do not form a closed circuit, then at step 303, a spool piece is searched whose end extends into the vicinity outside the jurisdiction, such spool piece being searchable, for example, by point capture techniques. Referring to FIG. 4, a spool piece 403 can be searched with its end extending out of the vicinity of jurisdiction 401. In step 304, a further search is made to traverse all of the tubing in the jurisdictional simulation model as well as loops extending out of the spool piece. With reference to FIG. 4, a closed loop can be formed by connecting extension spool piece 403 with spool piece 402 within jurisdiction 401, i.e., such a loop can be searched. If such a loop is searched (YES in step 305), the simulation data of the terminal is also used as a boundary condition of the simulation model of the jurisdiction. Therefore, sufficient boundary conditions can be obtained for the jurisdictional simulation model in a targeted manner to ensure smooth simulation calculation, and data of the adjacent simulation model (to which the extension pipe section belongs) can be prevented from being excessively leaked to the jurisdictional simulation model and users with lower authority.

Similarly, in some embodiments, the simulation data of the jurisdictional node corresponding to the boundary condition of the management unit simulation model in the jurisdictional simulation model of the jurisdiction to which the management unit belongs can be obtained through the following steps. And searching and traversing loops of all pipelines in the management unit simulation model. If such a loop is not searched, pipe segments whose ends extend out of the vicinity outside the management unit are searched. Further searching is performed for loops traversing all of the piping and extension pipe sections in the management unit simulation model. If such a loop is searched, the simulation data of the end is also used as a boundary condition of the management unit simulation model.

The end of the extended tube section 403 in fig. 4 may also be referred to as a transition point. For example, the area a and the area B are connected by 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 between the area a and the area B can be utilized to simplify the pipe network condition, and the information can be used as a transition point. This transition point may serve as a boundary condition for the simulation model of zone a. In some embodiments, the transition point may also exist between pipe networks with different pressure levels, and referring to fig. 2, a high-medium pressure regulating station 204 may be provided as a transition point between the city main pipe network 201 and the jurisdiction pipe network 202, and such a transition point between the city main simulation model and the jurisdiction simulation model is also referred to as a first-second transition point. Similarly, the transition point between the district simulation model and the management unit simulation model is referred to as a secondary-tertiary transition point.

In some embodiments, the simulation method may further comprise the following steps in relation to the transition point.

A primary-secondary transition point between the city trunk simulation model and the jurisdiction simulation model can be determined, the primary-secondary transition point is used for dividing the city trunk simulation model and the jurisdiction simulation model, and simulation data of the primary-secondary transition point is used as a boundary condition of the jurisdiction simulation model.

A second-third transition point between the jurisdiction simulation model and the management unit simulation model may be determined, the second-third transition point being used to partition the jurisdiction simulation model and the management unit simulation model, and simulation data of the second-third transition point being used as a boundary condition of the management unit simulation model. The boundary conditions of the corresponding level simulation model can be efficiently obtained through the determination of the transition points, so that accurate simulation analysis is realized. 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 for the management unit simulation model, but not at the 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 to fold and hide the pipe network or unfold the pipe network; under the condition that the interactive operation of the folding hidden pipe network is received by the indication of the user and the user has primary authority, only presenting the urban trunk simulation model at the upstream of the primary-secondary transition point; and only presenting the district simulation model at the upstream of the secondary-tertiary transition point under the condition that the interactive operation of the folding hidden pipe network of the user is received and the user has secondary authority.

In some embodiments, the simulation method further comprises: under the condition that the interactive operation of a pipe network is expanded and the user has a primary authority under the instruction of the user, the primary simulation system obtains the simulation data of the secondary simulation system and the tertiary simulation system, and the city main simulation model, the district simulation model and the management unit simulation model are presented in a connected mode; and under the condition that the interactive operation of the pipe network is expanded and the user has a secondary authority after receiving the instruction of the user, enabling the secondary simulation system to obtain the simulation data of the tertiary simulation system and connecting and presenting the jurisdiction simulation model and the management unit simulation model together.

Therefore, a user can freely select to fold and hide the pipe network or unfold the pipe network according to the concerned area, so that the simulation result of the urban trunk simulation model at the upstream or the district simulation model can be simply presented according to the real-time requirement, or the simulation result of the urban trunk simulation model or the low-level detail extended by the district simulation model can be comprehensively presented. Therefore, taking the city trunk simulation model as an example, a user with a primary authority, such as a dispatching center and/or a leading cockpit, can simply present the simulation result of the upstream city trunk simulation model, so as to initially locate the trunk fault area, and then expand and present the simulation result to view the simulation data of the jurisdiction simulation model corresponding to the trunk fault area, so as to confirm the fault area in the jurisdiction in a refined manner, thereby avoiding being submerged in a large amount of expanded detailed simulation data at the beginning, and further improving the analysis efficiency.

FIG. 5 shows an overview of the response and simulation flow of a four-stage gas emergency on a three-stage simulation system according to an embodiment of the application. As shown in fig. 5, the gas emergency is classified into a special major gas emergency, a major gas event, a general gas emergency, and a general gas emergency.

Specifically, one of the following events occurs, which is a particularly significant gas emergency: the problem of an upstream gas supply system causes gas supply abnormity in the whole city, so that the government starts an emergency supply plan; the emergency of the air supply system causes residents of more than 2 ten thousand households to stop supplying air; the normal use of the terminal user equipment cannot be met due to the change of gas components in an urban gas source or gas supply system.

Further, one of the following events occurs, which is a significant gas event: the abnormal gas supply system causes the overpressure operation or the gas supply shortage in local areas, and the alarm level above yellow specified by enterprises is reached; the large-area overpressure operation of the pipe network causes a large number of pipe networks or user facilities to break down and leak gas; the gas stopping quantity of resident users is more than 1 ten thousands of households to less than 2 ten thousands of households; a public canteen of a college and universities stops gas continuously for more than 24 hours; the SCADA monitoring system can not be recovered in a short period of paralysis, so that the operation of the gas supply system can not be normally monitored.

Further, one of the following events occurs in a general gas emergency: the gas stopping quantity of the resident users is more than 300 to less than 1 ten thousand; and the air supply of resident heating boilers is stopped during the heating period, or the air supply of large-range scattered heating users is stopped.

Further, the following events occur in the event of a common gas emergency: the number of the gas supply stop of the residential users is below 300.

As shown in fig. 5, in the case of an ordinary gas emergency, only users with three-level authority (shown as users with one star) are prompted, a three-level simulation system is called, and a simulation analysis is performed 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 that a common gas emergency happens, prompting a user with a third-level authority and a user with a second-level authority (shown as a user with two stars), calling a second-level simulation system, and performing 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 to guide maintenance and scheduling.

And under the condition of a major gas event or a particularly major gas emergency, prompting a user with a primary authority (shown as a user with three stars), a user with a secondary authority and a user with a tertiary authority, and performing collaborative simulation analysis on the city main stem 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.

Therefore, for each grade of gas emergency, the responsible person of the highest level required to provide guidance maintenance strategy for the event is automatically prompted, such as a dispatching center and/or a leading cockpit of a gas group, or a regional branch and/or a head office of the gas group, or an operation management unit under the jurisdiction of the regional branch and/or the head office of the gas group, and the responsible person of the highest level corresponding to the event can share simulation data from a subordinate simulation model of the responsible person of the subordinate level except for calling a simulation model related to the simulation data by itself, so that the simulation data required for guidance maintenance strategy is obtained in a targeted manner while redundant interference on other unrelated responsible persons is avoided, and responsibility distribution, comprehensive analysis and rapid processing of various gas emergency generated in multiple grades among the responsible persons of the gas group are facilitated.

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. 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 city trunk simulation models for calling, the secondary simulation system 600b is embedded with district simulation models 600b for calling, and the tertiary simulation system 600c is embedded with management unit simulation models 600c for calling. The 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 data to the shared database 600d and/or to obtain data from the shared database 600d that it has the right to obtain. For example, primary simulation system 600a has access to all data, while secondary simulation system 600b and tertiary simulation system 600 can only access data for its own modeling simulation and simulation data across other systems that is needed for its modeling simulation. By making the shared database 600d responsible for the behavior of sharing data according to the authority, the communication (which also receives the pipe network information from the GIS system and the SCADA monitoring system of the city gas pipe network) and the workload of each high-level system such as the primary simulation system 600a can be significantly reduced, thereby focusing more on the simulation analysis work.

Fig. 6 (b) shows a block diagram of a simulation platform of the city gas multi-stage pipe network according to the embodiment of the 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 an SCADA monitoring system from the urban gas multistage pipe network. The processor 602 may be configured to execute a simulation method of a city gas multi-stage pipe network according to various embodiments of the present application. For example, the simulation platform 600 may be implemented on a fixed server or may be implemented in 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, which, when executed by a processor, implement a method for simulating a city gas multi-stage pipe network according to various embodiments of the present application. The method may include the following steps. The first-level simulation system, the second-level simulation system and the third-level simulation system with sequentially reduced operation authority are provided, so that the first-level simulation system can obtain simulation data of the second-level simulation system and the third-level simulation system. And verifying the operation right of the user. Under the condition that a user has primary authority, acquiring pipe network data acquired by a GIS system and an SCADA monitoring system for a DN500 and above urban main pipe networks and associated affiliated structures by utilizing the primary simulation system, and establishing an urban main pipe simulation model of the urban gas pipe network according to the pipe network data. And carrying out simulation analysis on the city trunk simulation model to obtain simulation data of each trunk node. And under the condition that the user has secondary authority, acquiring the pipe network data acquired by the GIS system and the SCADA monitoring system for the DN300-500 district pipe network of the district and the associated accessory structures by using the secondary simulation system, and establishing a district simulation model of the urban gas pipe network according to the pipe network data. And acquiring simulation data of the trunk nodes corresponding to the boundary conditions of the district simulation model in the city trunk simulation model. And performing simulation analysis on the jurisdiction simulation model by using the simulation data of the corresponding trunk node as a boundary condition to obtain the simulation data of each jurisdiction node. Under the condition that a user has three levels of authority, acquiring pipe network data acquired by a GIS system and an SCADA monitoring system for DN50-300 management unit pipe networks of management units in jurisdictions and associated auxiliary structures by utilizing the three levels of simulation systems, and accordingly establishing a management unit simulation model of the urban gas pipe network. And acquiring simulation data of the district nodes corresponding to the boundary conditions of the management unit simulation model in the district simulation model of the district to which the management unit belongs. And performing simulation analysis on the management unit simulation model by using the simulation data of the corresponding jurisdictional node as a boundary condition to obtain the simulation data of each management unit node.

Examples of modeling simulation methods of other embodiments in the present application may be incorporated herein, and are not described herein again.

In some embodiments, the processor 602 may be, for example, a processing element comprising one or more general-purpose processors, such as a microprocessor, central Processing Unit (CPU), graphics Processing Unit (GPU), or the like.

The computer-readable storage medium is non-transitory and may be, for example, a read-only memory (ROM), a random-access memory (RAM), a phase-change random-access memory (PRAM), a static random-access memory (SRAM), a dynamic random-access memory (DRAM), an electrically erasable programmable read-only memory (EEPROM), other types of random-access memory (RAMs), a flash disk or other form of flash memory, a cache, a register, a static memory, a compact disc read-only memory (CD-ROM), a Digital Versatile Disc (DVD) or other optical storage, a magnetic tape or other magnetic storage device, or any other non-transitory medium that can be used to store information or instructions that can 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, which are not described herein.

Moreover, although exemplary embodiments have been described herein, the scope thereof includes any and all embodiments based on the present application with equivalent elements, modifications, omissions, combinations (e.g., of various embodiments across), adaptations or alterations. The elements of the claims are to be interpreted broadly based on the language employed in the claims and not limited to examples described in the present specification or during the prosecution of the 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 versions thereof) may be used in combination with each other. For example, other embodiments may be utilized by those of ordinary skill in the art upon reading the foregoing description. In addition, in the above detailed description, various features may be grouped together to streamline the application. This should not be interpreted as an intention that a disclosed feature not claimed is essential to any claim. Rather, subject matter of the present application may lie in less than all 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 each other 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 equivalents may be made by those skilled in the art within the spirit and scope of the present application and such modifications and equivalents should also be considered as falling within the scope of the present invention.

Claims

1. A simulation method for an urban gas multistage pipe network is characterized by comprising the following steps:

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 the operation right item of the user;

under the condition that the user has primary authority, by utilizing the primary simulation system,

acquiring pipe network data acquired by a GIS system and an SCADA monitoring system for a DN500 and above urban main pipe networks and associated auxiliary structures, and establishing an urban main stem simulation model of the urban gas pipe network according to the pipe network data;

carrying out simulation analysis on the city trunk simulation model to obtain simulation data of each trunk node;

in the case that the user has secondary rights, with the secondary emulation system,

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

acquiring simulation data of a trunk node corresponding to the boundary condition of the district simulation model in the city trunk simulation model;

performing simulation analysis on the jurisdiction simulation model by using the simulation data of the corresponding trunk node as a boundary condition to obtain the simulation data of each jurisdiction node;

in the case that the user has three levels of authority, with the three-level simulation system,

acquiring pipe network data acquired by a management unit pipe network of DN50-300 of management units in the administrative area and associated auxiliary structures by a GIS system and an SCADA monitoring system, and establishing a management unit simulation model of the urban gas pipe network according to the pipe network data;

acquiring simulation data of a district node corresponding to the boundary condition of the management unit simulation model in 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 to obtain the simulation data of each management unit node.

2. The simulation method of claim 1, further comprising:

and giving the primary authority to a dispatching center and/or a leading cockpit of the gas group, giving the secondary authority to a regional division company and/or a head office of the gas group, and giving the tertiary authority to an operation management unit under the jurisdiction of the regional division company and/or the head office 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 district pipe network is the medium pressure, and the pressure borne by the management unit pipe network is the low pressure;

carrying out simulation solution by using a transient non-isothermal equation system 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 of claim 1, further comprising:

the grade of the gas emergency is divided into a special important gas emergency, an important gas event, a general gas emergency and a general gas emergency,

among them, one of the following cases occurs, which is a particularly significant gas emergency: the problem of the upstream gas supply system causes abnormal gas supply in the whole city, so that the government starts an emergency supply plan; the emergency of the air supply system causes residents of more than 2 ten thousand households to stop supplying air; the change of the gas components in the urban gas source or gas supply system can not meet the normal use of the terminal user equipment,

one of the following occurrences is a major gas event: the abnormal gas supply system causes the overpressure operation or the gas supply shortage in local areas, and the alarm level above yellow specified by enterprises is reached; the large-area overpressure operation of the pipe network causes a large number of pipe networks or user facilities to break down and leak gas; the gas stopping quantity of the residential users is more than 1 ten thousands of households to less than 2 thousands of households; a public canteen of a college and universities stops gas continuously for more than 24 hours; the SCADA monitoring system can not be recovered in a short period of paralysis, so that the operation of the gas supply system can not be normally monitored,

one of the following events occurs in a typical gas emergency: the gas stopping quantity of the resident users is more than 300 to less than 1 ten thousand; the gas supply of resident heating boilers is stopped during the heating period, or the gas supply of distributed heating users in a large range is stopped,

the following situations occur and belong to common gas emergencies: the gas supply stop quantity of the resident users is below 300 households;

under the condition that a common gas emergency happens, only users with three-level authority are prompted, and a management unit simulation model of a management unit pipe network of the occurrence of the event is subjected to simulation analysis so as to guide maintenance and scheduling;

under the condition that a common gas emergency happens, prompting a user with a third-level authority and a user with a second-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 of a major gas event or a particularly major gas emergency, prompting a user with a primary authority, a user with a secondary authority and a user with a tertiary authority, and carrying out collaborative simulation analysis on the city main 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 of claim 1, wherein obtaining simulation data of a trunk node in the city trunk simulation model corresponding to a boundary condition of a jurisdictional simulation model further comprises;

searching and traversing loops of all pipelines in the district simulation model; if such a loop is not searched, then pipe sections with ends extending out of the neighborhood are searched; further searching and traversing all pipelines in the district simulation model and loops extending out of the pipe sections, and if such loops are searched, using the simulation data of the tail end as the boundary condition of the district simulation model; and/or

Obtaining simulation data of a jurisdiction node corresponding to a boundary condition of the management unit simulation model in a jurisdiction simulation model of a jurisdiction to which the management unit belongs, further comprises:

searching and traversing loops of all pipelines in the management unit simulation model; if such a loop is not searched, then pipe segments whose ends extend out of the administrative unit into the vicinity are searched; further searching for loops traversing all of the piping and extending pipe segments in the management unit simulation model, and if such loops are searched, also using the simulation data of the end as boundary conditions for the management unit simulation model.

6. The simulation method of claim 1, further comprising:

determining a primary-secondary transition point between the city trunk simulation model and the jurisdiction simulation model, wherein the primary-secondary transition point is used for dividing the city trunk simulation model and the jurisdiction simulation model;

determining a secondary-tertiary transition point between the jurisdictional simulation model and the management unit simulation model, wherein the secondary-tertiary transition point is used for dividing the jurisdictional simulation model and the management unit simulation model,

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

7. The simulation method of claim 6, further comprising:

receiving interactive operation of a user for indicating to fold and hide the pipe network or unfold the pipe network;

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

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

8. The simulation method of claim 6, further comprising:

under the condition that interactive operation of a pipe network is expanded and a user has a primary authority after receiving an instruction of the user, 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 main simulation model, the jurisdiction simulation model and the management unit simulation model;

and under the condition that the instruction of the user is received to expand the interactive operation of the pipe network and the user has a secondary authority, the secondary simulation system obtains the simulation data of the tertiary simulation system and is connected with and displays the jurisdiction simulation model and the management unit simulation model.

9. The utility model provides a simulation platform of multistage pipe network of city gas which characterized in that includes:

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

at least one processor configured to: a simulation method of the urban gas multistage pipe network according to any one of claims 1 to 8 is carried out.

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