CN114580129A - Method for performing dynamic simulation on gas pipe network based on pressure sampling data - Google Patents

Method for performing dynamic simulation on gas pipe network based on pressure sampling data Download PDF

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CN114580129A
CN114580129A CN202210397681.4A CN202210397681A CN114580129A CN 114580129 A CN114580129 A CN 114580129A CN 202210397681 A CN202210397681 A CN 202210397681A CN 114580129 A CN114580129 A CN 114580129A
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point
gas
absolute pressure
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pressure
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马卫涛
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Dongguan Hengli Xinghua Pipeline Gas Co ltd
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    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F30/00—Computer-aided design [CAD]
    • G06F30/10—Geometric CAD
    • G06F30/18—Network design, e.g. design based on topological or interconnect aspects of utility systems, piping, heating ventilation air conditioning [HVAC] or cabling
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17D—PIPE-LINE SYSTEMS; PIPE-LINES
    • F17D3/00—Arrangements for supervising or controlling working operations
    • F17D3/01—Arrangements for supervising or controlling working operations for controlling, signalling, or supervising the conveyance of a product
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17D—PIPE-LINE SYSTEMS; PIPE-LINES
    • F17D3/00—Arrangements for supervising or controlling working operations
    • F17D3/18—Arrangements for supervising or controlling working operations for measuring the quantity of conveyed product
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17D—PIPE-LINE SYSTEMS; PIPE-LINES
    • F17D5/00—Protection or supervision of installations
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F30/00—Computer-aided design [CAD]
    • G06F30/20—Design optimisation, verification or simulation
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F2113/00—Details relating to the application field
    • G06F2113/14—Pipes
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F2119/00—Details relating to the type or aim of the analysis or the optimisation
    • G06F2119/14—Force analysis or force optimisation, e.g. static or dynamic forces

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Abstract

The invention provides a method for dynamically simulating a gas pipe network based on pressure sampling data, which is characterized in that a medium pressure sensor and an atmospheric pressure sensor are installed near each source point, sink point and node of an urban pipe network, the medium absolute pressure and the atmospheric pressure of each point are monitored in real time, and the mutual relation between the absolute pressures of each point in a static state is obtained through an iterative algorithm, so that the influence of factors such as measurement errors of the pressure sensor and the like on a calculation result is eliminated. The method solves the technical problems that the existing gas pipe network simulation calculation method can not accurately master the gas flow information of the pipe network, can not find the abnormal condition of the gas flow rate in time and can not find the logic error in the pipe network in time. The invention can be widely applied to the field of dynamic monitoring of gas pipe networks.

Description

Method for performing dynamic simulation on gas pipe network based on pressure sampling data
Technical Field
The invention relates to a dynamic monitoring method of a gas pipe network, in particular to a method for performing dynamic simulation of the gas pipe network based on pressure sampling data.
Background
The fuel gas mainly refers to natural gas, and the natural gas has great strategy for national economy and sustainable development as smokeless industry and strategic industry with low consumption, high income, low pollution and high benefit. The gas is delivered to each household through the gas pipe network, and the real-time monitoring of the pressure, flow and other information of the gas pipe network is a necessary means for avoiding potential safety hazards in the gas delivery process.
With the popularization and development of the internet of things technology, the dynamic monitoring means of the urban pipe network is gradually maturing. The existing gas pipe network simulation calculation method can not accurately master the gas flow information of the pipe network, find the abnormal condition of the gas flow rate in time and find the logic error in the pipe network in time.
Disclosure of Invention
The invention provides a method for dynamically simulating a gas pipe network based on pressure sampling data, which can obtain pipe network gas flow information in real time, monitor abnormal gas flow and straighten the logic relationship of the pipe network, aiming at the technical problems that the pipe network gas flow information is difficult to accurately master, the abnormal gas flow condition is not found in time and the logic error in the pipe network cannot be found in time in the existing gas pipe network monitoring method.
In order to achieve the purpose, the invention is realized by the following technical scheme: a method for carrying out dynamic simulation on a gas pipe network based on pressure sampling data is characterized in that a medium pressure sensor and an atmospheric pressure sensor are mounted near each source point, each sink point and each node of an urban gas municipal pipe network, the medium pressure sensors are used for monitoring medium absolute pressure of each point in real time, the atmospheric pressure sensors are used for monitoring atmospheric pressure of each point in real time, static absolute pressure difference of each point is obtained through an iterative algorithm, and information of flow speed, flow direction, flow and gas consumption of gas in a pipeline is obtained through a hydraulic calculation formula.
Preferably, the specific steps of obtaining the static absolute pressure difference of each point through an iterative algorithm are as follows:
step 1, setting a source point as a set { A }, finding a point with highest air supply pressure in the set { A }, and setting A as A0Said setCombining other point elements in the { A } into (Ai), setting a node as a set { B }, setting any element in the set { B } into (Bi), setting a sink as a set { C }, and setting any element in the set { C } into (Ci);
step 2, taking data of each measuring point for 24 hours every day, finding out the absolute pressure value of the medium when the local gauge pressure is maximum, and setting the absolute pressure value as PInsulation boardRecord said PInsulation boardCorresponding time point is read, and the time point A is read0Absolute pressure value of point is P0Obtaining PInsulation board-P0Marking the static absolute pressure difference of the measuring point on the day, calculating every day, keeping the minimum value of the absolute values, iterating for a period of time, and determining all measuring points relative to A0Static absolute pressure difference of points, and keeping the signs of the points;
step 3, obtaining a static absolute pressure difference set { P) of all source pointsAi quiet}, set of static absolute pressure differences of all nodes { PBi quietSet of static absolute pressure differences of all sinks { P }Ci Jing}。
Preferably, an arbitrary node Bi is taken as a center, the connected pipe sections are Gi, i is an integer, and the adjacent points are points with arbitrary properties of a source point, a node and a sink point, and according to the point pairs A0And (4) calculating the static absolute pressure value between the Bi point and all the adjacent points around the Bi point according to the static absolute pressure difference value of the points.
Preferably, the method for acquiring the flow direction of the fuel gas in the pipeline comprises the following steps: let Bi and the static absolute pressure difference of some adjacent point be Delta PiStatic stateSetting the absolute pressure value of Bi point measured at a certain moment as PBi testThe absolute pressure value of a certain adjacent point is measured to be PAdjacent side surveyWhen P isAdjacent side survey-PBi test-△PiStatic stateWhen the flow rate is more than 0, the medium flow in the pipe section Gi is from the adjacent point to the point Bi, when P isAdjacent side survey-PBi test-△PiStatic stateWhen the flow rate is less than 0, the medium flow in the pipe section Gi is that Bi points flow to adjacent points, and when P isAdjacent side survey-PBi test-△PiStatic stateTowards 0, the media in the pipe section Gi does not flow.
Preferably, let Δ PiDynamic state＝PAdjacent side survey-PBi test-△PiStatic stateWhen Δ PiDynamic state>At 0 hour, throughMass flows from adjacent point to Bi point, then pi＝PBi test，pj＝PBi test-△PiDynamic state(ii) a When Δ PiDynamic state<At 0, the medium flows from the Bi point to the adjacent point, then pj＝PBi test，pi＝PBi test+△PiDynamic stateAnd pi is the absolute pressure of the inlet node of the pipe section, and pj is the absolute pressure of the outlet node of the pipe section.
Preferably, the hydraulic calculation formula of the high-pressure and medium-pressure gas pipe sections is as follows:
Figure BDA0003598164230000031
Figure BDA0003598164230000032
in the formula:
pi、pj-absolute pressure, kPa, at the pipe section inlet and outlet nodes;
l-the length of the pipe section, km;
λ -coefficient of friction resistance of the pipe section;
qk-gas flow in the Standard State, m3/h；
d-inner diameter of the pipe section, mm;
rho-density of gas, kg/m30.7174 at 0 ℃ and 101.325 KPa;
t-temperature of the gas, unit: k, T ═ T0+ t ℃, wherein t is the medium temperature;
z is a gas compression factor, and when the gas pressure is less than 1.2MPa, 1 is taken;
T0-gas temperature in standard state, in units: k, taking T0＝273.16k；
K is the equivalent absolute roughness of the inner surface of the pipe section;
Re-Reynolds number.
The invention has the beneficial effects that:
(1) the method comprises the steps of obtaining gas flow information of a pipe network in real time through measuring pressure of each point, grasping gas flow direction, obtaining medium flow rate through calculation, and monitoring abnormal flow and sudden large leakage events of the gas;
(2) the logical relationship of the management network can be orderly managed, and logical errors can be timely found;
(3) the neck pipe sections can be found in time, design basis is provided for pipe network construction, and data support is provided for gas network allocation and visual management.
Detailed Description
The invention will be further elucidated with reference to the embodiments of the invention described hereinafter.
A method for carrying out dynamic simulation on a gas pipe network based on pressure sampling data comprises the following steps of installing medium pressure sensors and atmospheric pressure sensors near source points, sinks and nodes of an urban gas municipal pipe network, monitoring the absolute pressure and the atmospheric pressure of media of each point in real time, and obtaining the mutual relation between the absolute pressures of the points in a static state through an iterative algorithm, so that the influence of factors such as measurement errors of the pressure sensors on the calculation result is eliminated, wherein the method comprises the following specific steps:
step 1, setting a source point as a set { A }, finding a point with highest air supply pressure in the set { A }, and setting the point as A0The elements of other points are (Ai), the nodes are set as a set { B }, any element is (Bi), the sink is set as a set { C }, and any element is (Ci);
step 2, taking data of each measuring point for 24 hours every day, and finding out local gauge pressure (P)Insulation board-Pa) The maximum absolute pressure of the medium (at which the local fluidity is minimal) is designated as PInsulation boardRecord the PInsulation boardCorresponding time point is read, and the time point A is read0Absolute pressure value of point is P0Obtaining PInsulation board-P0The static absolute pressure difference of the measuring point on the day is marked, the minimum value of the absolute value is obtained every day, iteration is carried out for a period of time, for example, 30 days, and all measuring points are determined relative to A0Static absolute pressure difference of points, and keeping the signs of the points;
step 3, obtaining { P of all source pointsAi quiet{ P } of all nodesBi quiet{ P of all sinksCi quietAnd centering on any node Bi, setting the connected pipe sections as Gi (i is 1, 2 and 3.), setting adjacent points as points with any properties such as source points, nodes and sinks, and according to each point pair A0The static absolute pressure value between the Bi point and all the adjacent points around is obtained.
Let Bi and the static absolute pressure difference of some adjacent point be Delta PiStatic stateSetting the absolute pressure value of Bi point measured at a certain moment as P, wherein the corresponding pipe section is GiBi testThe absolute pressure value of a certain adjacent point is measured to be PAdjacent side surveySuch as PAdjacent side survey-PBi test-△PiStatic stateIf > 0, the medium flow in the pipe section Gi is from the adjacent point to the point Bi, e.g. PAdjacent side survey-PBi test-△PiStatic stateIf < 0, the medium flow in the pipe section Gi is Bi point flow to adjacent point, such as PAdjacent side survey-PBi test-△PiStatic stateTowards 0, the media in the pipe section Gi does not flow. Here, 0 is intended to be equal to 0 or close to 0.
And processing the acquired information, and obtaining the flow direction of the medium in the pipe section where the point is located according to the static absolute pressure difference and the absolute pressure value of the point and the absolute pressure value of the adjacent point obtained through processing.
Let Δ PiDynamic state＝PAdjacent side survey-PBi test-△PiStatic stateDetermining the import-export relationship between Bi point and adjacent point (by P)Side by side-PBi test-△PiStatic state"the value of the flow direction is judged, and further the import-export relationship is determined), p is set according to the import-export relationshipi＝PBi testAnd pj＝PBi test-△PiDynamic stateOr pj＝PBi testAnd pi＝PBi test+△PiDynamic stateAnd calculating to obtain the information of the flow speed, the flow direction, the flow and the gas consumption of the pipe section Gi.
The hydraulic calculation formula of the high-pressure and medium-pressure gas pipe sections is as follows:
Figure BDA0003598164230000051
Figure BDA0003598164230000052
in the formula:
pi、pj-absolute pressure, kPa, at the pipe section inlet and outlet nodes;
l-the length of the pipe section, km;
λ -coefficient of friction resistance of the pipe section;
qk-gas flow in the Standard State, m3/h；
d-inner diameter of the pipe section, mm;
rho-density of gas, kg/m3(0.7174 at 0 ℃ and 101.325 KPa);
t-temperature of the gas, unit: k, (T ═0+ t ℃), where t is the medium temperature;
z is gas compression factor (when the gas pressure is less than 1.2MPa, 1 is taken);
T0-gas temperature in standard state, in units: k, (take T)0＝273.16k)；
K is the equivalent absolute roughness of the inner surface of the pipe section;
Re-Reynolds number.
And repeating the calculation to obtain the dynamic flow information of all the pipe sections in any pressure state, thereby realizing the dynamic simulation of the pipe network.
The method comprises the steps of obtaining gas flow information of a pipe network in real time through measuring pressure of each point, grasping gas flow direction, obtaining medium flow rate through calculation, and monitoring abnormal flow and sudden large leakage events of the gas; the logical relationship of the management network can be orderly managed, and logical errors can be timely found; the neck pipe sections can be found in time, design basis is provided for pipe network construction, and data support is provided for gas network allocation and visual management.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.

Claims (6)

1. A method for carrying out dynamic simulation on a gas pipe network based on pressure sampling data is characterized in that a medium pressure sensor and an atmospheric pressure sensor are installed near each source point, sink point and node of an urban gas municipal pipe network, the medium pressure sensor is used for monitoring medium absolute pressure of each point in real time, the atmospheric pressure sensor is used for monitoring atmospheric pressure of each point in real time, static absolute pressure difference of each point is obtained through an iterative algorithm, and information of flow velocity, flow direction, flow and gas consumption of gas in a pipeline is obtained through a hydraulic calculation formula.
2. The method for performing dynamic simulation on a gas pipe network based on pressure sampling data according to claim 1, wherein the specific step of obtaining the static absolute pressure difference of each point through an iterative algorithm is as follows:
step 1, setting a source point as a set { A }, finding a point with the highest gas supply pressure in the set { A }, and setting the point as A0Setting the node as a set { B }, any element in the set { B } as (Bi), and a sink as a set { C }, and any element in the set { C } as (Ci);
step 2, taking data of each measuring point for 24 hours every day, finding out the absolute pressure value of the medium when the local gauge pressure is maximum, and setting the absolute pressure value as PInsulation boardRecord said PInsulation boardCorresponding time point is read, and the time point A is read0Absolute pressure value of point is P0Obtaining PInsulation board-P0Marking the static absolute pressure difference of the measuring point on the day, calculating every day, keeping the minimum value of the absolute values, iterating for a period of time, and determining all measuring points relative to A0Static absolute pressure difference of points, and keeping the signs of the points;
step 3, obtaining a static absolute pressure difference set { P) of all source pointsAi quiet}, set of static absolute pressure differences of all nodes { PBi quietSet of static absolute pressure differences of all sinks { P }Ci quiet}。
3. The method for performing dynamic simulation on a gas pipe network based on pressure sampling data according to claim 1, wherein an arbitrary node Bi is taken as a center, connected pipe sections are Gi, i is an integer, and adjacent points are points with arbitrary properties such as source points, nodes and sinks, and A is determined according to each point pair0And (4) calculating the static absolute pressure value between the Bi point and all the adjacent points around the Bi point according to the static absolute pressure difference value of the points.
4. The method for performing dynamic simulation on a gas pipe network based on pressure sampling data according to claim 3, wherein the method for acquiring the flow direction of gas in a pipeline comprises the following steps: let the static absolute pressure difference between Bi and some adjacent point be Δ PiStatic stateSetting the absolute pressure value of Bi point measured at a certain moment as P, wherein the corresponding pipe section is GiBi testThe absolute pressure value of a certain adjacent point is measured to be PAdjacent side surveyWhen P isAdjacent side survey-PBi test-△PiStatic stateWhen the flow rate is more than 0, the medium flow in the pipe section Gi is from the adjacent point to the point Bi, when P isAdjacent side survey-PBi test-△PiStatic stateWhen the flow rate is less than 0, the medium flow in the pipe section Gi is that Bi points flow to adjacent points, and when P isSide by side-PBi test-△PiStatic stateTowards 0, the media in the pipe section Gi does not flow.
5. The method for gas pipeline network dynamic simulation based on pressure sampling data as claimed in claim 4, wherein Δ Pi is setDynamic state＝PAdjacent side survey-PBi test-△PiStatic stateWhen Δ PiDynamic state>At 0, the medium flows from the adjacent point to the Bi point, then pi＝PBi test，pj＝PBi test-△PiDynamic state(ii) a When Δ PiDynamic state<At 0, the medium flows from the Bi point to the adjacent point, then pj＝PBi test，pi＝PBi test+△PiDynamic stateAnd pi is the absolute pressure of the inlet node of the pipe section, and pj is the absolute pressure of the outlet node of the pipe section.
6. The method for performing dynamic simulation on a gas pipe network based on pressure sampling data according to claim 5, wherein hydraulic calculation formulas of the high-pressure gas pipe section and the medium-pressure gas pipe section are as follows:
Figure FDA0003598164220000021
Figure FDA0003598164220000022
in the formula:
pi、pj-absolute pressure, kPa, at the pipe section inlet and outlet nodes;
l-the length of the pipe section, km;
λ -coefficient of friction resistance of the pipe section;
qk-gas flow in the Standard State, m3/h；
d-inner diameter of the pipe section, mm;
rho-density of gas, kg/m30.7174 at 0 ℃ and 101.325 KPa;
t-temperature of the gas, unit: k, T ═ T0+ t ℃, wherein t is the medium temperature;
z is a gas compression factor, and when the gas pressure is less than 1.2MPa, 1 is taken;
T0-gas temperature in standard state, in units: k, taking T0＝273.16k；
K is the equivalent absolute roughness of the inner surface of the pipe section;
Re-Reynolds number.
CN202210397681.4A 2022-04-15 2022-04-15 Method for performing dynamic simulation on gas pipe network based on pressure sampling data Pending CN114580129A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114878108A (en) * 2022-07-08 2022-08-09 山东拙诚智能科技有限公司 Gas flow monitoring method and device
CN115875614A (en) * 2023-02-23 2023-03-31 山东拙诚智能科技有限公司 Device and method for detecting gas pipeline leakage through medium pressure disturbance signal

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114878108A (en) * 2022-07-08 2022-08-09 山东拙诚智能科技有限公司 Gas flow monitoring method and device
CN115875614A (en) * 2023-02-23 2023-03-31 山东拙诚智能科技有限公司 Device and method for detecting gas pipeline leakage through medium pressure disturbance signal
CN115875614B (en) * 2023-02-23 2023-06-06 山东拙诚智能科技有限公司 Device and method for detecting leakage of gas pipeline through medium pressure disturbance signal

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