Method and device for regulating and controlling heating system based on digital twinborn model

Abstract

The embodiment of the invention provides a heating system regulation and control method based on a digital twinborn model, and belongs to the technical field of intelligent heating, and the method comprises the following steps: inputting specified weather data into a pre-constructed heating system digital twinborn model, and obtaining a heat transfer calculation model corresponding to the specified weather data; wherein the heating system digital twinborn model is constructed according to input characteristic parameters, and the input characteristic parameters comprise heating equipment parameters, pipeline parameters, a heating process and weather data; the heating system digital twinborn model comprises heat transfer calculation models under different weather data; and utilizing the heat transfer calculation model to perform simulation calculation on a shell pass heat transfer coefficient, a tube pass heat transfer coefficient and a total heat transfer coefficient of the heat exchange equipment, and regulating and controlling the heating system according to one or more indexes of the shell pass heat transfer coefficient, the tube pass heat transfer coefficient and the total heat transfer coefficient. According to the embodiment of the invention, full-process node data of the heat supply pipe network can be simulated and calculated, and intelligent regulation and control are realized.

Description

Technical Field

[0001] The present invention relates to the technical field of intelligent heating, and particularly to a control method and device for a heating system based on a digital twin model. Background Art

[0002] Central heating refers to a way of supplying steam and hot water generated by a central heat source to a city or a part of the area through a pipe network to meet the heat requirements for production, heating and living. Central heating is an important infrastructure for building a modern city. It can not only provide a stable and reliable high-quality heat source for the city, but also save energy and reduce energy consumption. The central heating system mainly consists of three parts: a heat source, a heat supply pipe network, and target users. Among them, the heat sources for central heating include power plants with combined heat and power, central boiler houses, industrial and other waste heat, geothermal energy, nuclear energy, solar energy, heat pumps, etc. The heat supply pipe network includes the connection relationship between heating equipment and pipes. However, the structure of the heat supply pipe network is complex and the scope is wide, making it difficult for humans to accurately and quickly understand the operation status of the pipe network. Moreover, the number of instruments in the heating system is limited, and there are basically only instruments for metering in the heat exchange station, and the flow meter metering is prone to errors. Summary of the Invention

[0003] The purpose of the embodiments of the present invention is to provide a control method and device for a heating system based on a digital twin model. Through the embodiments of the present invention, the problems existing in the prior art can be solved or partially solved. To achieve the above purpose, the embodiments of the present invention provide a control method for a heating system based on a digital twin model, and the method includes:

[0004] Input the specified weather data into a pre-constructed digital twin model of the heating system to obtain a heat transfer calculation model corresponding to the specified weather data; wherein,

[0005] The digital twin model of the heating system is constructed according to the input characteristic parameters, and the input characteristic parameters include heating equipment parameters, pipe parameters, heating process, and weather data;

[0006] The heating process includes the connection relationship between heating equipment and pipes in the heat supply pipe network; the digital twin model of the heating system includes heat transfer calculation models under different weather data;

[0007] The heat transfer calculation model is used to simulate and calculate the shell-side heat transfer coefficient, tube-side heat transfer coefficient, and total heat transfer coefficient of the heat exchange equipment;

[0008] Utilize the heat transfer calculation model to simulate and calculate the shell-side heat transfer coefficient, tube-side heat transfer coefficient, and total heat transfer coefficient of the heat exchange equipment, and control the heating system according to one or more of the shell-side heat transfer coefficient, the tube-side heat transfer coefficient, and the total heat transfer coefficient.

[0009] Optionally, the heat supply network node includes the input and output nodes of heating equipment and pipelines.

[0010] Optionally, the digital twin model of the heating system further includes a hydraulic calculation model under different weather data;

[0011] Input the specified weather data into the pre-constructed digital twin model of the heating system to obtain the hydraulic calculation model corresponding to the specified weather data;

[0012] The hydraulic calculation model is used to simulate and calculate the flow rate, flow velocity, and pressure of the heat supply network nodes;

[0013] Utilize the hydraulic calculation model to simulate and calculate the flow rate, flow velocity, and pressure of the heat supply network nodes, and regulate the heating system according to one or more of the flow rate, flow velocity, and pressure of the heat supply network nodes.

[0014] Optionally, the characteristic parameters for constructing the digital twin model of the heating system further include altitude and coordinate information;

[0015] The altitude is used to represent the altitude of the heating equipment and pipelines;

[0016] The coordinate information is used to determine the actual distribution positions of the heating equipment and pipelines.

[0017] Optionally, the heating equipment parameters include: structural parameters, operating parameters, and physical property parameters;

[0018] Among them, the structural parameters include the number of heating equipment, size, and number of tube passes; the operating parameters include: flow rate, pressure, and temperature; the physical property parameters include medium type, density, viscosity, specific heat at constant pressure, and thermal conductivity;

[0019] The pipeline parameters include: pipe diameter, wall thickness, length, insulation material, and insulation layer thickness.

[0020] Optionally, the heating equipment includes: heat exchange equipment, circulation pumps, and heat exchange units.

[0021] Optionally, the flow rate and pressure of the heat supply network nodes are calculated by the following method:

[0022] Determine one or more source nodes in the heat supply network. For each of these source nodes, measure the flow rate and pressure of the input and output nodes corresponding to the source node under the specified weather data;

[0023] Input the flow rate and pressure of the input and output nodes corresponding to the source node under the specified weather data into the hydraulic calculation model;

[0024] The hydraulic calculation model simulates and calculates the flow rate and pressure corresponding to the remaining nodes in the heat supply network under the specified weather data.

[0025] Optionally, the heat transfer calculation model is also used to simulate and calculate the temperature of the nodes in the heat supply network.

[0026] Optionally, the temperature of the nodes in the heat supply network is calculated in the following manner:

[0027] Determine one or more source nodes in the heat supply network. For each of these source nodes, measure the temperatures of the input and output nodes corresponding to the source node under the specified weather data respectively;

[0028] Input the temperatures of the input and output nodes corresponding to the source node under the specified weather data into the heat transfer calculation model;

[0029] The heat transfer calculation model simulates and calculates the temperatures corresponding to the remaining nodes in the heat supply network under the specified weather data.

[0030] Optionally, the flow velocity u of the nodes in the heat supply network is calculated by the following formula:

[0031]

[0032] where m is the mass flow rate, ρ is the fluid density, and s is the cross-sectional area of the pipe;

[0033] And the flow velocity and pressure of the nodes in the heat supply network satisfy the following relationship:

[0034]

[0035] where g is the acceleration due to gravity, Z is the height difference between the input and output nodes of the pipe, p is the node pressure, ρ is the fluid density, u is the flow velocity, and C is a constant.

[0036] Optionally, the tube-side heat transfer coefficient h t is calculated according to the following formula:

[0037]

[0038] where C is a coefficient. For gases, C = 0.021; for non-viscous liquids, C = 0.023; for viscous liquids, C = 0.027; k t is the tube-side fluid thermal conductivity, with the unit of W / (m·℃); Pr is the Prandtl number; Re is the Reynolds number; μ t is the tube-side working fluid viscosity, with the unit of Pa·s; μ tw is the fluid viscosity on the tube wall, with the unit of Pa·s; d i is the inner diameter of the heat exchange tube;

[0039] The shell-side heat transfer coefficient is calculated by the following formula:

[0040] h s = h IS F hn F hw F hb F hl

[0041] In the formula: h s is the shell-side heat transfer coefficient, with the unit of W / (m2·℃); h IS is the theoretical shell-side heat transfer coefficient for ideal cross-flow; F hn is the correction factor; F hw is the window correction coefficient; F hb is the bypass flow correction factor, F hl is the leakage correction coefficient;

[0042] The overall heat transfer coefficient of the heat exchange equipment is calculated according to the following formula:

[0043]

[0044] where U is the overall heat transfer coefficient of the heat exchange equipment; h s is the shell-side heat transfer coefficient; h sf is the shell-side fouling resistance, with the unit of W / (m2·℃); h w is the tube wall heat transfer coefficient, with the unit of W / (m2·℃); d0 is the outer diameter of the heat exchange tube, with the unit of mm; d i is the inner diameter of the heat exchange tube, with the unit of mm; h tf is the tube-side fouling resistance, with the unit of W / (m2·℃); h t is the tube-side heat transfer coefficient.

[0045] Optionally, the regulation of the heating system according to one or more of the shell-side heat transfer coefficient, the tube-side heat transfer coefficient, and the overall heat transfer coefficient includes:

[0046] Determine the position of the thermal resistance according to the tube-side heat transfer coefficient, the shell-side heat transfer coefficient, and the overall heat transfer coefficient; after determining the position of the thermal resistance, the heating system issues a warning and displays the thermal resistance node;

[0047] Compare the shell-side heat transfer coefficient with a preset threshold. When the error between the two is large, the heating system issues a warning after determining the heat exchange equipment corresponding to the shell-side heat transfer coefficient and displays the heat exchange equipment.

[0048] Optionally, the method further includes: comparing the temperature of the heat supply network node with the corresponding original design value, and when the error is greater than a preset error range, the heating system displays the corresponding node and issues a warning.

[0049] Optionally, the regulation of the heating system according to one or more of the flow rate, flow velocity, and pressure of the heat supply network node includes:

[0050] comparing the pressure of the heat supply network node with the corresponding original design value, and when the error is greater than a preset error range, the heating system displays the corresponding node and issues a warning;

[0051] comparing the flow velocity of the heat supply network node with the corresponding original design value, and when the error is greater than a preset error range, the heating system displays the flow velocity value and the corresponding node and issues a warning.

[0052] Optionally, the heat transfer calculation model is further used to calculate the total heat transfer coefficient of the pipeline, and the total heat transfer coefficient of the pipeline is calculated according to the following formula:

[0053]

[0054] where k represents the total heat transfer coefficient of the pipeline; d0 is the outer diameter of the pipeline, d i is the inner diameter of the pipeline, α i is the heat transfer coefficient of the fluid inside the pipeline, a0 is the heat transfer coefficient of the fluid outside the pipeline, δ is the thickness of the pipeline, λ0 is the thermal conductivity of the pipe material, d m is the average diameter, and d m , d0, d i , satisfy the following formula:

[0055]

[0056] Optionally, the heat transfer calculation model is further used to calculate the heat exchange efficiency, and the heat exchange efficiency is used to evaluate the optimizable space of the heating system.

[0057] The heat exchange efficiency is calculated according to the following formula:

[0058]

[0059] where Q1 is the actual heat transfer load, Q2 is the theoretical heat transfer load, and e is the heat exchange efficiency; the actual heat transfer load Q1 is calculated according to the following formula:

[0060] Q1 = U·A0·ΔT

[0061] where U is the total heat transfer coefficient of the heat exchange equipment, A0 is the heat transfer area based on the outside of the pipe, and ΔT is the temperature difference between the inlet pipe and the outlet pipe of the tube-side fluid.

[0062] Optionally, when establishing the digital twin model of the heating system, some of the nodes of the heat supply pipe network are preselected, and the pressure values and temperature values of the preselected nodes of the heat supply pipe network measured by instruments are used to correct the model parameters.

[0063] Optionally, the digital twin model of the heating system is further configured to simulate the indoor temperature of the target heating user under different weather data according to the input different weather data.

[0064] On the other hand, an embodiment of the present invention provides a control device for a heating system, which includes a processor configured to perform the control method for a heating system based on a digital twin model as described above.

[0065] On the one hand, the control method for a heating system based on a digital twin model according to an embodiment of the present invention can, in advance for various weather conditions, simulate and predict the corresponding operation data of the heating system under the specific weather data, so as to formulate corresponding heating strategies, reduce energy consumption, and improve the energy efficiency of the heating system; on the other hand, it can simulate and calculate the full-process node data of the heat supply pipe network, and on this basis, make calibration and adjustment in combination with the actual situation, with high simulation accuracy and reliable calculation.

[0066] Other features and advantages of the embodiments of the present invention will be described in detail in the subsequent specific implementation part. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] The accompanying drawings are used to provide a further understanding of the embodiments of the present invention, and constitute a part of the specification. They are used together with the following specific implementation to explain the embodiments of the present invention, but do not constitute a limitation to the embodiments of the present invention. In the accompanying drawings:

[0068] Figure 1 is a flowchart of the control method for a heating system based on a digital twin model provided by an embodiment of the present invention;

[0069] Figure 2 is a flowchart of the method for calculating the flow rate and pressure of the nodes of the heat supply pipe network provided by an embodiment of the present invention;

[0070] Figure 3 is a schematic diagram of the digital twin model of the heating system in the West Yanshan area provided by an embodiment of the present invention;

[0071] Figure 4 is a schematic diagram of the digital twin model of the heating system in the East Yanshan area provided by an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0072] The following will describe in detail the specific implementation of the embodiments of the present invention with reference to the accompanying drawings. It should be understood that the specific implementation described herein is only used to illustrate and explain the embodiments of the present invention, and is not used to limit the embodiments of the present invention.

[0073] Figure 1 It is a flowchart of a regulation method for a heating system based on a digital twin model provided by an embodiment of the present invention; Figure 3 It is a schematic diagram of a digital twin model of the Yanshan West District heating system provided by an embodiment of the present invention; Figure 4 It is a schematic diagram of a digital twin model of the Yanshan East District heating system provided by an embodiment of the present invention.

[0074] As Figure 1 shown, the regulation method includes:

[0075] Step S101: Input specified weather data into a pre-constructed digital twin model of the heating system to obtain a heat transfer calculation model corresponding to the specified weather data.

[0076] A digital twin model of a heating system provided by an embodiment of the present invention is as Figure 3 shown, and another digital twin model of the heating system is as Figure 4 shown.

[0077] Furthermore, the weather data includes index values such as temperature, humidity, wind force, and weather conditions (sunny, cloudy, rainy, snowy), etc. The specified weather data can be the daily weather data of the target application location of the heating system, the monthly average of various index data of the monthly weather data, or the quarterly average of various index data of the weather data in the winter heating season.

[0078] Among them, the digital twin model of the heating system is constructed according to the input characteristic parameters. The input characteristic parameters include heating equipment parameters, pipeline parameters, heating process, and weather data.

[0079] It should be noted that when establishing the digital twin model of the heating system, some of the heat supply network nodes are preselected, and the pressure values and temperature values of the preselected part of the heat supply network nodes measured by instruments are used to correct the model parameters.

[0080] Specifically, the heating equipment involved mainly includes one or more of the following equipment: shell-and-tube heat exchanger, pipeline, circulation pump, lithium bromide large temperature difference heat exchange unit.

[0081] Furthermore, the heating equipment parameters are specifically described in combination with the heating equipment. The heat exchanger structure parameters include: the number of heat exchange tubes, the size of heat exchange tubes, the length of heat exchange tubes, and the number of tube passes. The rated parameters of the circulation pump include: rated flow, rated head, and rated efficiency. The rated parameters of the circulation pump include: rated flow, rated head, and rated efficiency. The rated parameters of the lithium bromide unit include the inlet and outlet flow rates, pressures, and temperatures of the heat source, chilled water, and cooling water, and the operating characteristic parameters of the generator, absorber, condenser, and evaporator.

[0082] It should be noted that the heating equipment parameters also include operating parameters and physical properties parameters. Among them, the operating parameters include the flow rate, pressure, and temperature of the process materials. The physical properties parameters include: medium type, density, viscosity, specific heat at constant pressure, and thermal conductivity.

[0083] The pipeline parameters include: pipe diameter, wall thickness, length, insulation layer material, and insulation layer thickness.

[0084] The heating process includes the connection relationship between the heating equipment and the pipeline in the heat supply network. Further, the heat supply network includes multiple heat supply network nodes, and the heat supply network nodes include the input and output nodes of the heating equipment and the pipeline.

[0085] Specifically, the heating process also includes the connection relationships between the waste heat heat source, the heat supply first station, the primary water pipeline, the heat supply end station and the pipeline respectively.

[0086] It should be noted that the characteristic parameters for constructing the digital twin model of the heating system also include altitude and coordinate information. Among them, the altitude is used to represent the altitude of the heating equipment and the pipeline; the coordinate information is used to determine the actual distribution position of the heating equipment and the pipeline. Selecting the altitude as the input feature mainly considers the influence of height on water pressure. The higher the altitude, the smaller the atmospheric pressure. Selecting the coordinate information as the input feature can make the finally constructed digital twin model of the heating system more accurate, and further reduce the errors of various physical quantities determined according to the digital twin model of the heating system.

[0087] The digital twin model of the heating system includes a heat transfer calculation model under different weather data.

[0088] Specifically, the heat transfer calculation model is used to simulate and calculate the shell-side heat transfer coefficient, tube-side heat transfer coefficient, and total heat transfer coefficient of the heat exchange equipment. Among them, the heat exchange equipment is preferably a shell-and-tube heat exchanger.

[0089] The digital twin model of the heating system provided by the embodiments of the present invention can adjust the equipment and pipelines, simulate and calculate the operating data before and after the adjustment, so as to compare the operating data before and after the replacement, calculate the benefits, and evaluate the effects of the adjustment measures.

[0090] Specifically, digital twin refers to the use of various types of data such as physical models, sensor data, and operating data to integrate the simulation processes of multiple disciplines, multiple physical quantities, multiple scales, and multiple probabilities, and complete the mapping in the virtual space, so as to reflect the entire life cycle process of the corresponding physical equipment. Digital twin is widely used in fields such as product design, product manufacturing, medical analysis, and engineering construction.

[0091] Step S102: Using a heat transfer calculation model, simulate and calculate the shell-side heat transfer coefficient, tube-side heat transfer coefficient, and overall heat transfer coefficient of the heat exchange equipment.

[0092] Among them, the tube-side heat transfer coefficient h t is calculated according to the following formula:

[0093]

[0094] Among them, C is a coefficient. For gases, C = 0.021; for non-viscous liquids, C = 0.023; for viscous liquids, C = 0.027; k t is the tube-side fluid thermal conductivity, with the unit of W / (m·°C); Pr is the Prandtl number; Re is the Reynolds number; μ t is the tube-side working fluid viscosity, with the unit of Pa·s; μ tw is the fluid viscosity on the tube wall, with the unit of Pa·s; d i is the inner diameter of the heat exchange tube;

[0095] It should be noted that the Reynolds number Re is determined based on the flow velocity calculated by the hydraulic calculation model.

[0096] The shell-side heat transfer coefficient is calculated according to the following formula:

[0097] h s = h IS F hn F hw F hb F hl

[0098] In the formula: h s is the shell-side heat transfer coefficient, with the unit of W / (m2·°C); h IS is the theoretical shell-side heat transfer coefficient for ideal cross-flow; F hn is the correction factor. For turbulent flow, F hn is close to 1.0; F hw is the window correction coefficient. For heat exchangers with high design accuracy, the value of F hw is close to 1.0; F hb is the bypass flow correction factor. A conservative assumption is that both the clean and contaminated conditions are 0.8, but fouling tends to increase its value to close to 1.0; F hl is the leakage correction coefficient. A conservative assumption is that both the clean and contaminated conditions are 0.8, but fouling tends to increase its value to close to 1.0.

[0099] The overall heat transfer coefficient of the heat exchange equipment is calculated according to the following formula:

[0100]

[0101] Among them, U is the overall heat transfer coefficient of the heat exchange equipment; h s is the heat transfer coefficient of the shell side; h sf is the fouling thermal resistance of the shell side, with the unit of W / (m2·℃); h w is the heat transfer coefficient of the tube wall, with the unit of W / (m2·℃); d0 is the outer diameter of the heat exchange tube, with the unit of mm; d i is the inner diameter of the heat exchange tube, with the unit of mm; h tf is the fouling thermal resistance of the tube side, with the unit of W / (m2·℃); h t is the heat transfer coefficient of the tube side.

[0102] According to this formula, it can be known that if the value of either the heat transfer coefficient of the tube side or the heat transfer coefficient of the shell side is small, the overall heat transfer coefficient of the heat exchange equipment will be reduced; if the heat transfer coefficients at both ends are not much different, fouling will become the main factor affecting the heat transfer effect.

[0103] Furthermore, the heat transfer calculation model is also used to calculate the heat exchange efficiency, and the heat exchange efficiency is used to evaluate the optimizable space of the heating system.

[0104] Among them, the heat exchange efficiency is calculated according to the following formula:

[0105]

[0106] Among them, Q1 is the actual heat transfer load, Q2 is the theoretical heat transfer load, and e is the heat exchange efficiency; the actual heat transfer load Q1 is calculated according to the following formula:

[0107] Q1 = U·A0·ΔT

[0108] Among them, U is the overall heat transfer coefficient of the heat exchange equipment, A0 is the heat transfer area based on the outside of the tube, and ΔT is the temperature difference between the inlet pipe and the outlet pipe of the tube side fluid.

[0109] It should be noted that the heat exchange process can be analyzed, combined with the process of the waste heat heat source material, to obtain the theoretical lowest temperature after heat exchange, so as to determine the theoretical heat transfer load.

[0110] According to the calculation formula of the actual heat transfer load, the larger the total heat transfer system, the more the heat exchange quantity, and the larger the temperature difference; the lower the heat exchange efficiency, the larger the optimizable space. If the heat exchange equipment is severely aged and the deviation of the heat exchange efficiency from the corresponding original design value is large, the replacement benefit and the investment payback period can be calculated by replacing some of the aged equipment and simulating the effect after replacement. The reason can also be further analyzed. If the low heat exchange efficiency is due to the small heat exchange area, the heat exchange area can be increased accordingly. The operation situation after transformation is re-simulated according to the corresponding adjustment measures, and the transformation benefit is calculated.

[0111] Furthermore, the heat transfer calculation model is also used to calculate the overall heat transfer coefficient of the pipeline. The heat transfer process of the pipeline includes five links: from the fluid inside the pipe to the inner wall of the pipe, from the inner wall of the pipe to the outer wall of the pipe, from the outer wall of the pipe to the inner wall of the insulation layer, from the inner wall of the insulation layer to the outer wall of the insulation layer, and from the outer wall of the insulation layer to the ambient atmosphere. The overall heat transfer coefficient of the pipeline is based on the outer surface area of the insulation layer and is calculated according to the following formula:

[0112]

[0113] Among them, k represents the overall heat transfer coefficient of the pipeline; d0 is the outer diameter of the pipeline, d i is the inner diameter of the pipeline, α i is the heat transfer coefficient of the fluid inside the pipe, a0 is the heat transfer coefficient of the fluid outside the pipe, δ is the thickness of the pipeline, λ0 is the thermal conductivity of the pipe material, d m is the average diameter, and d m , d0, d i satisfy the following formula:

[0114]

[0115] For a low-viscosity fluid in forced turbulence inside a circular pipeline, the heat transfer coefficient of the fluid inside the pipeline or the heat transfer coefficient of the fluid outside the pipeline both satisfy the following formula:

[0116]

[0117] The coefficients and exponents in the formula are all obtained through experiments. a is the heat transfer coefficient of the fluid inside the pipeline or the heat transfer coefficient of the fluid outside the pipeline, λ is the thermal conductivity of the fluid, d i is the inner diameter of the pipeline, u is the flow velocity of the fluid inside the pipeline, ρ is the density of the fluid, μ is the viscosity of the fluid, c p is the specific heat at constant pressure.

[0118] It should be noted that the flow velocity of the fluid inside the pipeline is determined according to the hydraulic calculation model.

[0119] Step S103, regulate the heating system according to one or more of the shell-side heat transfer coefficient, the tube-side heat transfer coefficient, and the overall heat transfer coefficient of the heat exchange equipment.

[0120] Specifically, regulating the heating system according to one or more of the shell-side heat transfer coefficient, the tube-side heat transfer coefficient, and the overall heat transfer coefficient includes:

[0121] Determine the position of the thermal resistance according to the tube-side heat transfer coefficient, the shell-side heat transfer coefficient, and the overall heat transfer coefficient; after determining the position of the thermal resistance, the heating system issues a warning and displays the thermal resistance node.

[0122] Specifically, thermal resistance refers to the degree of obstruction to heat transfer in an object and is usually used to describe the limitation of the heat transfer ability of materials, structures, or systems. For example, after determining the location of the thermal resistance, further analysis is carried out on the pipeline node corresponding to the thermal resistance. If the thermal resistance is caused by equipment aging, the corresponding equipment needs to be replaced.

[0123] Compare the shell-side heat transfer coefficient with a preset threshold. When the error between the two is large, the heating system issues a warning after determining the heat exchange equipment corresponding to the shell-side heat transfer coefficient and displays the heat exchange equipment.

[0124] Specifically, according to the characteristics of the shell-side heat transfer coefficient formula, when the values corresponding to the cleanliness and pollution status indicators in the pipeline are too high, the shell-side heat transfer coefficient correspondingly increases. Therefore, the determined pipeline node can be descaled or part of the pipeline can be replaced to make the shell-side heat transfer coefficient close to the original design value.

[0125] Furthermore, the heat transfer calculation model is also used for simulating and calculating the temperature of the heat supply network nodes, and the temperature of the heat supply network nodes is calculated by the following method:

[0126] Step 401: Determine one or more source nodes in the heat supply network. For each of these source nodes, measure the temperatures of the corresponding input and output nodes under specified weather data respectively;

[0127] Specifically, the source nodes in the heat supply network are multiple selected heat exchange stations, and the temperatures of the primary water and secondary water are measured actually using instruments.

[0128] Step 402: Input the temperatures of the input and output nodes of the heat supply network nodes (including heating equipment and pipelines) into the heat transfer calculation model;

[0129] Step 403: The heat transfer calculation model simulates and calculates the temperatures corresponding to the remaining nodes in the heat supply network under specified weather data.

[0130] When the supply temperature or return temperature of the primary water and / or secondary water exceeds the corresponding preset threshold, the heating system displays the corresponding temperature value and issues a warning.

[0131] When the supply temperature of the primary water exceeds the corresponding preset threshold, it is prompted to reduce the load of the peak heat exchanger at the heat supply first station to lower the supply temperature of the primary water. For example, reduce the steam flow of the steam heater. Among them, the primary water is the water in the pipeline between the heat source and the intermediate heat exchange station, and the secondary water is the water in the heating pipeline between the intermediate heat exchange station and the target heating households.

[0132] Further, the temperature of the heat supply network node can be compared with the corresponding original design value. When the error is greater than the preset error range, the heating system displays the corresponding heat supply network node and issues a warning.

[0133] The digital twin model of the heating system further includes a hydraulic calculation model under different weather data. The control method of the heating system based on the digital twin model further includes:

[0134] Step S201: Input the specified weather data into the pre-constructed digital twin model of the heating system to obtain the hydraulic calculation model corresponding to the specified weather data.

[0135] Further, the hydraulic calculation model is used to simulate and calculate the flow rate, flow velocity, and pressure of the heat supply network node.

[0136] Step S202: Use the hydraulic calculation model to simulate and calculate the flow rate, flow velocity, and pressure of the heat supply network node.

[0137] Figure 2 It is a flowchart of the method for calculating the flow rate and pressure of the heat supply network node provided by the embodiment of the present invention. As Figure 2 shown, the flow rate and pressure of the heat supply network node are calculated by the following method:

[0138] Step S301: Determine one or more source nodes in the heat supply network. For each of these source nodes, measure the flow rate and pressure of the input and output nodes corresponding to the source node under the specified weather data respectively.

[0139] Specifically, the source nodes in the heat supply network are multiple selected heat exchange stations, and the flow rate and pressure of the primary water and secondary water are measured by instruments.

[0140] Step S302: Input the flow rate and pressure of the input and output nodes corresponding to the source node under the specified weather data into the hydraulic calculation model.

[0141] Step S303: The hydraulic calculation model simulates and calculates the flow rate and pressure corresponding to the remaining nodes in the heat supply network under the specified weather data.

[0142] In the existing heating system, the number of instruments is limited, and there are basically only instruments for measurement in the heat exchange station. The flow velocity, pressure, and temperature of the heat supply network not covered by the instruments are still unknown; moreover, the flow rate, pressure, and temperature measured by the instruments are prone to errors. However, the hydraulic calculation model provided by the embodiment of the present invention can simulate and calculate the flow velocity, pressure, and temperature data corresponding to all process nodes in the heat supply network under the specified weather data.

[0143] Further, the flow velocity u of the heat supply network node is calculated by the following formula:

[0144]

[0145] Wherein, m is the mass flow rate, ρ is the fluid density, and s is the cross-sectional area of the pipeline;

[0146] And the flow velocity and pressure of the heating pipe network node satisfy the following relationship:

[0147]

[0148] Wherein, g is the acceleration due to gravity, Z is the height difference between the input and output nodes of the pipeline, p is the node pressure, ρ is the fluid density, u is the flow velocity, and C is a constant.

[0149] It should be noted that according to the above equation, the pressure difference between adjacent nodes can also be calculated based on the mass flow rate m.

[0150] Step S203, adjust the heating system according to one or more of the flow rate, flow velocity, and pressure of the heating pipe network node.

[0151] Specifically, adjusting the heating system according to one or more of the flow rate, flow velocity, and pressure of the heating pipe network node includes:

[0152] Compare the flow rate, flow velocity, and pressure of the heating pipe network node with the corresponding original design values respectively. When the error of any one of the indicators is greater than the preset error range, the heating system displays the corresponding node and issues a warning.

[0153] Specifically, the heating pipe network node includes the input and output nodes of the heating equipment and the pipeline. The heating system in the embodiment of the present invention can visually display the specific position information of the input and output nodes of the heating equipment and the pipeline in the heating pipe network, such as distribution position coordinate data and the corresponding altitude.

[0154] The heating system provided by the embodiment of the present invention can realize centralized monitoring and visual display of the full-process node data of the heating pipe network, such as viewing parameters that are not metered, such as the flow velocity, heat preservation, and heat dissipation of each pipeline segment; viewing the operating status of each heat exchange equipment, and managing and monitoring the heat supply, transportation, and user end usage of waste heat, so as to realize process control and intelligent regulation.

[0155] Furthermore, the digital twin model of the heating system is also used to simulate the indoor temperature of the target heating user under different weather data according to the input different weather data. Specifically, the heat transfer calculation model can be used to simulate and calculate the temperature of the heating pipe network node, and the target heating user is a part of the specified nodes in the heating pipe network node.

[0156] According to the national standard "Code for Residential Design", the indoor heating calculation temperature of the bedrooms and living rooms in ordinary residences should not be lower than 18°C. By adjusting the primary water supply temperature multiple times, the lowest primary water supply temperature can be obtained under various environmental temperatures to meet the condition that the indoor temperature is higher than 18°C, which plays a reference role for heating units. The heating system provided by the embodiments of the present invention can simulate and predict the heating temperature in advance for various weather conditions, so as to formulate corresponding heating strategies.

[0157] It should be noted that, on the one hand, the regulation method of the heating system provided by the embodiments of the present invention can independently analyze one of the various indicators simulated and calculated by the heat transfer calculation model and the hydraulic calculation model to regulate the heating system; on the other hand, it can comprehensively analyze the various indicators simulated and calculated by the heat transfer calculation model and the hydraulic calculation model to regulate the heating system.

[0158] Specifically, Figure 3 is a schematic diagram of the digital twin model of the heating system in the west area of Yanshan provided by the embodiments of the present invention; Figure 4 is a schematic diagram of the digital twin model of the heating system in the east area of Yanshan provided by the embodiments of the present invention.

[0159] Referring to Figure 3 、 Figure 4 , the modeling scope of the west area of Yanshan includes: the waste heat source of the refinery, the west area first station, the primary water pipe network, the Dongfeng end station, the Yangeryu west area end station, and the Yangeryu end station. The modeling scope of the east area of Yanshan includes: the waste heat of the chemical plant, the east area first station, the primary water pipe network, and the Beizhuang end station. According to the heating system model in the west area of Yanshan and the heating system model in the east area of Yanshan, first analyze the bottleneck of the heat exchange pipe network. If there are pipelines with too slow or too fast flow rates, optimize suggestions for replacing the pipelines are put forward; then analyze the temperature drop of the pipelines. If there are pipelines with too large temperature drop and appropriate flow rate, optimize suggestions for replacing the pipeline insulation are put forward; finally, calculate and analyze the heat exchange efficiency of the heat exchange equipment. If the heat exchange efficiency of the equipment is low, optimize suggestions for replacing high-efficiency equipment are put forward.

[0160] The above are only the embodiments of the present application and are not used to limit the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the scope of the claims of the present application.

Claims

1. A control method for a heating system based on a digital twin model, characterized in that, The method includes: Inputting specified weather data into a pre - constructed digital twin model of a heating system to obtain a heat transfer calculation model corresponding to the specified weather data; wherein, The digital twin model of the heating system is constructed based on the input characteristic parameters, and the input characteristic parameters include heating equipment parameters, pipeline parameters, heating process, and weather data; The heating process includes the connection relationship between heating equipment and pipelines in the heat supply network; The digital twin model of the heating system includes heat transfer calculation models under different weather data; The heat transfer calculation model is used to simulate and calculate the shell - side heat transfer coefficient, tube - side heat transfer coefficient, and overall heat transfer coefficient of the heat exchange equipment; Using the heat transfer calculation model, simulate and calculate the shell - side heat transfer coefficient, tube - side heat transfer coefficient, and overall heat transfer coefficient of the heat exchange equipment, and regulate the heating system according to one or more of the shell - side heat transfer coefficient, tube - side heat transfer coefficient, and overall heat transfer coefficient.

2. The method according to claim 1, characterized in that, The heat supply network nodes include the input and output nodes of heating equipment and pipelines.

3. The method according to claim 2, wherein The digital twin model of the heating system further includes a hydraulic calculation model under different weather data; Inputting specified weather data into a pre - constructed digital twin model of a heating system to obtain a hydraulic calculation model corresponding to the specified weather data; The hydraulic calculation model is used to simulate and calculate the flow rate, flow velocity, and pressure of the heat supply network nodes; Using the hydraulic calculation model, simulate and calculate the flow rate, flow velocity, and pressure of the heat supply network nodes, and regulate the heating system according to one or more of the flow rate, flow velocity, and pressure of the heat supply network nodes.

4. The method according to claim 1, characterized in that The characteristic parameters for constructing the digital twin model of the heating system further include altitude and coordinate information; The altitude is used to represent the altitude of heating equipment and pipelines; The coordinate information is used to determine the actual distribution position of heating equipment and pipelines.

5. The method according to claim 1, wherein The heating equipment parameters include: structural parameters, operating parameters, and physical property parameters; Wherein, the structural parameters include the number of heating equipment, size, and the number of tube passes; the operating parameters include: flow rate, pressure, and temperature; the physical property parameters include the type of medium, density, viscosity, specific heat at constant pressure, and thermal conductivity; The pipeline parameters include: pipe diameter, wall thickness, length, insulation material, and insulation layer thickness.

6. The method according to claim 1, characterized in that The heating equipment includes: heat exchange equipment, circulation pumps, and heat exchange units.

7. The method according to claim 3, wherein The flow rate and pressure of the heat supply network nodes are calculated by the following method: Determine one or more source nodes in the heat supply network, and for each of these source nodes, measure the flow rate and pressure of the input and output nodes corresponding to the source node under specified weather data; Input the flow rate and pressure of the input and output nodes corresponding to the source node under specified weather data into the hydraulic calculation model; The hydraulic calculation model simulates and calculates the flow rate and pressure corresponding to the remaining nodes in the heat supply network under specified weather data.

8. The method according to claim 2, wherein The heat transfer calculation model is also used to simulate and calculate the temperature of the heat supply network nodes.

9. The method according to claim 8, wherein The temperature of the heat supply network node is calculated in the following manner: Determine one or more source nodes in the heat supply network. For each of these source nodes, measure the temperatures of the corresponding input and output nodes under specified weather data respectively; Input the temperatures of the corresponding input and output nodes of the source node under the specified weather data into the heat transfer calculation model; The heat transfer calculation model simulates and calculates the temperatures of the remaining nodes in the heat supply network corresponding to the specified weather data.

10. The method according to claim 3, characterized in that, The flow velocity u of the heat supply network node is calculated by the following formula: where m is the mass flow rate, ρ is the fluid density, and s is the cross-sectional area of the pipe; And the flow velocity and pressure of the heat supply network node satisfy the following relationship: where g is the acceleration due to gravity, Z is the height difference between the input and output nodes of the pipe, p is the node pressure, ρ is the fluid density, u is the flow velocity, and C is a constant.

11. The method according to claim 1, wherein The tube-side heat transfer coefficient h t is calculated according to the following formula: Among them, C is a coefficient. For gases, C = 0.021; for non-viscous liquids, C = 0.023; for viscous liquids, C = 0.027; k t is the thermal conductivity of the tube-side fluid, with the unit of W / (m·°C); Pr is the Prandtl number; Re is the Reynolds number; μ t is the viscosity of the tube-side working medium, with the unit of Pa·s; μ tw is the fluid viscosity on the tube wall, with the unit of Pa·s; d i is the inner diameter of the heat exchange tube; The shell-side heat transfer coefficient is calculated by the following formula: h s = h IS F hn F hw F hb F hl Where: h s is the shell-side heat transfer coefficient, with the unit of W / (m2·℃); h IS is the theoretical shell-side heat transfer coefficient for ideal cross flow; F hn is the correction factor; F hw is the window correction coefficient; F hb is the bypass flow correction factor, F hl is the leakage correction coefficient; The overall heat transfer coefficient of the heat exchange equipment is calculated according to the following formula: Among them, U is the overall heat transfer coefficient of the heat exchange equipment; h s is the heat transfer coefficient of the shell side; h sf is the fouling thermal resistance of the shell side, with the unit of W / (m2·℃); h w is the heat transfer coefficient of the tube wall, with the unit of W / (m2·℃); d0 is the outer diameter of the heat exchange tube, with the unit of mm; d i is the inner diameter of the heat exchange tube, with the unit of mm; h tf is the fouling thermal resistance of the tube side, with the unit of W / (m2·℃); h t is the heat transfer coefficient of the tube side.

12. The method according to claim 1, characterized in that, Regulating the heating system according to one or more of the shell-side heat transfer coefficient, the tube-side heat transfer coefficient, and the overall heat transfer coefficient includes: Determine the position of the thermal resistance according to the tube-side heat transfer coefficient, the shell-side heat transfer coefficient, and the overall heat transfer coefficient; after determining the position of the thermal resistance, the heating system issues a warning and displays the thermal resistance node; Compare the shell-side heat transfer coefficient with a preset threshold value. When the error between the two is large, after determining the heat exchange equipment corresponding to the shell-side heat transfer coefficient, the heating system issues a warning and displays the heat exchange equipment.

13. The method according to claim 8, wherein This method further includes: comparing the temperature of the heat supply network node with the corresponding original design value. When the error is greater than the preset error range, the heating system displays the corresponding node and issues a warning.

14. The method according to claim 3, wherein Regulating the heating system according to one or more of the flow rate, flow velocity, and pressure of the heat supply network node includes: Compare the pressure of the heat supply network node with the corresponding original design value. When the error is greater than the preset error range, the heating system displays the corresponding node and issues a warning; Compare the flow velocity of the heat supply network node with the corresponding original design value. When the error is greater than the preset error range, the heating system displays the flow velocity value and the corresponding node and issues a warning.

15. The method according to claim 1, wherein The heat transfer calculation model is also used to calculate the overall heat transfer coefficient of the pipe, and the overall heat transfer coefficient of the pipe is calculated according to the following formula: where k represents the overall heat transfer coefficient of the pipe; d0 is the outer diameter of the pipe, and d i is the inner diameter of the pipe, α i is the heat transfer coefficient of the fluid inside the pipe, a0 is the heat transfer coefficient of the fluid outside the pipe, δ is the pipe thickness, λ0 is the thermal conductivity of the pipe material, and d m is the average diameter, and d m , d0, and d i satisfy the following formula:

16. The method according to claim 1, characterized in that, The heat transfer calculation model is also used to calculate the heat exchange efficiency, and the heat exchange efficiency is used to evaluate the optimizable space of the heating system, The heat exchange efficiency is calculated according to the following formula: where Q1 is the actual heat transfer load, Q2 is the theoretical heat transfer load, and e is the heat exchange efficiency; the actual heat transfer load Q1 is calculated by the following formula: Q1 = U·A0·ΔT where U is the overall heat transfer coefficient of the heat exchange equipment, A0 is the heat transfer area based on the outside of the tube, and ΔT is the temperature difference between the inlet and outlet pipes of the tube-side fluid.

17. The method according to claim 1, characterized in that, When establishing the digital twin model of the heating system, some of the nodes of the heat supply pipe network are preselected, and the pressure values and temperature values of the preselected nodes of the heat supply pipe network measured by instruments are used to correct the model parameters.

18. The method according to claim 1, characterized in that, The digital twin model of the heating system is also used to simulate the indoor temperature of the target heating users under different weather data according to the input different weather data.

19. A control device for a heating system, the device includes a processor, and the processor is configured to execute the control method of the heating system based on the digital twin model according to claims 1 to 18.

Images