A simulation method for the water hammer process of a single-phase fluid network

Abstract

The present invention discloses a simulation method for the water hammer process in a single-phase fluid network. The solution includes: dividing nodes and streamlines based on the characteristics of the pipe network and filling in the input card; reading the data of the input card and initializing the simulation calculation of the single-phase fluid network; selecting a single-phase fluid network algorithm to calculate the node pressure, enthalpy value, and streamline flow rate; updating the thermal and hydraulic states of the nodes and streamlines; determining whether to perform the water hammer calculation for the single-phase fluid network; recording the thermal and hydraulic states of the single-phase fluid network and initializing the water hammer for the single-phase fluid network; performing the water hammer calculation for the single-phase fluid network and updating the node pressure and streamline flow rate. Solving the temperature field of the single-phase fluid network and updating the thermal state of the nodes; determining whether to continue the water hammer calculation for the single-phase fluid network. If the water hammer calculation time is reached, the water hammer calculation is ended; otherwise, the calculation of the next water hammer time step Δt2 is continued; determining whether to continue the single-phase fluid network calculation, and the judgment basis is the calculation time in the input card.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrodynamic simulation, and in particular, to a simulation method for the water hammer process of a single-phase fluid network. Background Art

[0002] A single-phase fluid network is a pipe network system composed of pipelines, valves, pumps, hot plates, water tanks, and other fluid machinery and heat exchange equipment, and the working medium is a single-phase fluid. Single-phase fluid network simulation mainly uses the node pressure method to divide the pipe network system into a fluid network model composed of basic elements such as internal nodes, streamlines, boundary nodes, and hot plates, and simplifies the complex transmission problems in the pipe network system into the problems of solving the transient pressure of nodes and the flow rate of streamlines. This method has the advantages of small calculation amount, stable calculation, and the ability to achieve real-time simulation. Therefore, single-phase fluid network simulation is mostly applied to the development of simulators for energy and power systems, the operation research of thermal systems, and design verification.

[0003] Water hammer is a physical process in which pressure waves propagate to adjacent nodes due to the transient operation of fluid machinery in a pipeline, after the pressure and flow rate deviate from the initial steady-state values. This process is often accompanied by huge noise and violent vibration, and in severe cases, it will cause pipeline fatigue fracture and equipment failure. Therefore, accurately calculating the water hammer process has important engineering value for the operation safety and design of pipe networks. Currently, few single-phase fluid network simulations can perform water hammer process simulations. The main reasons are as follows: 1. To meet the real-time requirements, single-phase fluid network simulations have been greatly simplified both in terms of models and solution methods, and cannot calculate the water hammer process; 2. Existing water hammer calculations mostly use the method of characteristics for calculation. This method needs to meet the Courant condition, and the node selection is denser than that of single-phase fluid networks, and the pipe network needs to be re-divided, resulting in a sharp increase in the calculation amount and difficult coupling between programs. Therefore, it is necessary to provide a new simulation method for the water hammer process of a single-phase fluid network to couple single-phase fluid network simulation and water hammer simulation, make up for the deficiency that single-phase fluid network simulation cannot perform water hammer process simulation, and expand the application scope of single-phase fluid network simulation technology. Summary of the Invention

[0004] The present invention provides a simulation method for the water hammer process of a single-phase fluid network to overcome at least one technical problem existing in the prior art.

[0005] According to an embodiment of the present invention, a simulation method for the water hammer process of a single-phase fluid network is provided, including:

[0006] Step S1: Divide nodes and streamlines based on the pipe network characteristics of the pipe network system composed of a condenser, a pump, and a pressure vessel, and fill in the input card;

[0007] Step S2: Read the data of the input card and perform the initialization of single-phase fluid network simulation calculation;

[0008] Step S3: Select the single-phase fluid network algorithm to calculate the node pressure, enthalpy value, and streamline flow rate; update the thermal-hydraulic state of the nodes and streamlines, and output the key parameters; specifically including:

[0009] List the single-phase fluid network mathematical model shown in the following formulas:

[0010]

[0011]

[0012]

[0013] Equation (1) is the node mass conservation equation, Equation (2) is the node energy conservation equation, and Equation (3) is the streamline momentum conservation equation. In the equations, the symbol V represents the volume of the node; the symbol ρ represents the density of the node; the symbol D represents the incidence matrix between the nodes, D ij = 1 indicates flowing from node j to node i, D ij = 0 indicates no connection between node i and node j, D ij = -1 indicates flowing from node i to node j; the symbol G represents the flow value between the nodes; the symbol Y represents the value range of the node numbers as [1, Y]; the symbol M represents the mass of the node; the symbol P represents the pressure of the node; the symbol v represents the specific volume of the node; the symbol G in represents the flow rate flowing into node i; the symbol G out represents the flow rate flowing out of node i; the symbol h represents the specific enthalpy value of the node; the symbol K represents the heat transfer coefficient between the node and the environment; the symbol A h represents the heat transfer area between the node and the environment; the symbol T represents the node temperature; the symbol T0 represents the environmental temperature; the symbol Q represents the heat absorption or internal heat source of the node; the symbol W represents the work done by the node; the symbol L represents the streamline length; the symbol A represents the flow cross-sectional area of the streamline; the symbol Hpump represents the head of the pump on the streamline; the symbol Hg represents the gravity pressure difference on the streamline; the symbol f represents the frictional pressure drop and local pressure drop on the streamline;

[0014] Step S4: Determine whether to perform single-phase fluid network water hammer calculation;

[0015] Step S5: Record the thermal-hydraulic state of the single-phase fluid network and perform single-phase fluid network water hammer initialization;

[0016] Step S6: Use the wave tracking method to perform single-phase fluid network water hammer calculation and update the node pressure and streamline flow rate;

[0017] Among them, Steps S5 and S6 specifically include: Select the wave tracking method to solve the water hammer. The expression of the wave tracking method is as follows:

[0018]

[0019]

[0020] Among them, the symbol f represents the downstream wave in the positive direction of the flow rate in the single-phase fluid network topology; the symbol F represents the upstream wave in the negative direction of the flow rate in the single-phase fluid network topology; the symbol P represents the node pressure; the symbol P0 represents the steady-state node pressure; the symbol G represents the node mass flow rate; the symbol G0 represents the steady-state node mass flow rate; the symbol a represents the wave speed; the symbol A c represents the cross-sectional area of the streamline; the expression for the propagation process of the water hammer wave in the pipeline is:

[0021]

[0022]

[0023] Among them, the subscripts A and B respectively represent the upstream and downstream nodes of the streamline; the symbol f A represents the downstream wave at node A; f B represents the downstream wave at node B, and the symbol L AB represents the length of the streamline between node A and node B; the symbol ρ represents the streamline density; the symbol J represents the streamline friction loss; the symbol J0 represents the steady-state streamline friction loss;

[0024] Step S7, solve the temperature field of the single-phase fluid network and update the thermal state of the nodes;

[0025] Step S8, determine whether to continue the water hammer calculation of the single-phase fluid network. The judgment basis is the water hammer calculation time given in the online debugging stage. If the water hammer calculation time is reached, the water hammer calculation is ended; otherwise, continue the calculation of the next water hammer time step Δt2 and return to Step S6;

[0026] Step S9, determine whether to continue the single-phase fluid network calculation. The judgment basis is the calculation time in the input card. When the calculation time is reached, the calculation is ended; otherwise, continue the calculation of the next time step Δt1.

[0027] Preferably, the input card includes a flow network quantity card, a calculation card, a pressure boundary data card, a flow rate boundary data card, an internal node data card, a streamline data card, a pump data card, and a hot plate data card.

[0028] Preferably, the calculation card includes the type of calculation, calculation start time, calculation step size, calculation end time, and fluid type; the pressure boundary data card includes the pressure of the pressure boundary nodes and the enthalpy value; the flow boundary data card includes the flow rate of the flow boundary nodes and the enthalpy value; the internal node data card includes the pressure, flow rate, and enthalpy value of the internal nodes. The internal node data card serves as the initial data, and the data of the flow boundary nodes and pressure boundary nodes serve as the boundary conditions; the streamline data card includes the topological structure between nodes, streamline geometric parameters, etc.; the pump data card includes the rated parameters of the pump; the hot plate data card includes the geometric parameters of the hot plate, heat transfer coefficient, and node connection relationship.

[0029] At least one embodiment of this specification can achieve the following beneficial effects:

[0030] 1. The present invention uses input cards to input the data required for single-phase fluid network simulation calculations, making the data input concise and standardized, and improving the program usage efficiency. By identifying whether to perform water hammer calculations for the single-phase fluid network during the online debugging stage and supplementing the water hammer calculation data through the online window, the coupling between the single-phase fluid network simulation and the single-phase fluid network water hammer simulation is realized, and the independence between the two is strong.

[0031] 2. The present invention uses the wave tracking method for water hammer calculations. Compared with other solution methods, the water hammer calculation efficiency is greatly improved. The influence of temperature field changes on water hammer calculations is considered during the single-phase fluid network water hammer calculation process, improving the solution accuracy and being closer to the real physical process.

[0032] 3. A single-phase fluid network water hammer process simulation method proposed by the present invention makes up for the deficiency that the single-phase fluid network simulation cannot perform water hammer process simulation, and expands the application scope of the single-phase fluid network simulation. Description of the Drawings

[0033] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0034] Figure 1 is a flowchart of a single-phase fluid network water hammer process simulation method provided by the present invention;

[0035] Figure 2 is a pipe network system diagram composed of a condenser, a pump, and a pressure tank;

[0036] Figure 3 is a schematic diagram of the node streamline division of the pipe network system;

[0037] Figure 4 It is a schematic diagram of the parameter information related to the input card;

[0038] Figure 5 It is a schematic diagram of modifying the pump speed during the online debugging stage;

[0039] Figure 6 It is a curve graph of the changes in pump flow rate, pressure, and condenser outlet temperature during a power-off pump stop accident. Specific implementation manners

[0040] To make the objectives, technical solutions, and advantages of one or more embodiments of this specification clearer, the technical solutions of one or more embodiments of this specification will be clearly and completely described below in conjunction with the specific embodiments of this specification and the corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this specification, rather than all the embodiments. Based on the embodiments in this specification, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope protected by one or more embodiments of this specification.

[0041] It should be understood that although terms such as first, second, and third may be used in this application document to describe various information, such information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other.

[0042] Figure 1 It is a schematic flow diagram of a simulation method for the water hammer process of a single-phase fluid network provided for the embodiments of this specification.

[0043] As Figure 1 shown, the process may include the following steps.

[0044] Step S1: Divide nodes and streamlines according to the characteristics of the pipe network and fill in the input card

[0045] As Figure 2 shown, the simulation object is a pipe network system composed of a condenser, a pump, and a pressure vessel. According to its characteristics, it can be divided into pressure boundary nodes, internal nodes, streamlines, and hot plates, as Figure 3 shown. Figure 4The input cards in it include a streamline network quantity card, a calculation card, a pressure boundary data card, a flow boundary data card, an internal node data card, a streamline data card, a pump data card, and a hot plate data card. The calculation card includes the type of calculation, the start time of calculation, the calculation step size, the end time of calculation, and the fluid type; the pressure boundary data card includes the pressure and enthalpy value of the pressure boundary nodes; the flow boundary data card includes the flow rate and enthalpy value of the flow boundary nodes; the internal node data card includes the pressure, flow rate, and enthalpy value of the internal nodes. The internal node data card is mainly used as initial data, and the data of the flow boundary nodes and pressure boundary nodes are used as boundary conditions; the streamline data card includes the topological structure between nodes, streamline geometric parameters, etc.; the pump data card includes the rated parameters of the pump; the hot plate data card includes the geometric parameters of the hot plate, the heat transfer coefficient, the node connection relationship, etc.

[0046] Step S2: Read the input card data and initialize the single-phase fluid network simulation calculation.

[0047] Step S3: Select a single-phase fluid network algorithm to calculate the node pressure, enthalpy value, and streamline flow rate;

[0048] Step S4: Update the thermo-hydraulic state of the nodes and streamlines and output the key parameters;

[0049] Steps S3 and S4 are the core steps of the single-phase fluid network simulation calculation. The single-phase fluid network mathematical model:

[0050]

[0051]

[0052] Equation (1) is the node mass conservation equation, Equation (2) is the node energy conservation equation, and Equation (3) is the streamline momentum conservation equation. In the equations, the symbol V represents the volume of the node; the symbol ρ represents the density of the node; the symbol D represents the incidence matrix between nodes. D ij = 1 indicates flowing from node j to node i, D ij = 0 indicates that there is no connection between node i and node j, D ij = -1 indicates flowing from node i to node j; the symbol G represents the flow value between nodes; the symbol Y represents the value range of the node number as [1, Y]; the symbol M represents the mass of the node; the symbol P represents the pressure of the node; the symbol v represents the specific volume of the node; the symbol G in represents the flow rate flowing into node i; the symbol G out represents the flow rate flowing out of node i; the symbol h represents the specific enthalpy value of the node; the symbol K represents the heat transfer coefficient between the node and the environment; the symbol A hIt represents the heat exchange area between the node and the environment; the symbol T represents the node temperature; the symbol T0 represents the environmental temperature; the symbol Q represents the heat absorption or internal heat source of the node; the symbol W represents the work done by the node; the symbol L represents the streamline length; the symbol A represents the flow cross-sectional area of the streamline; the symbol Hpump represents the head of the pump on the streamline; the symbol Hg represents the gravitational pressure difference on the streamline; the symbol f represents the frictional pressure drop and local pressure drop on the streamline.

[0053] The single-phase fluid network algorithms mainly include the separation algorithm and the coupling algorithm. In the separation algorithm, the pressure field is calculated first, then the flow field, and finally the temperature field. In the coupling algorithm, the temperature field and the pressure field are solved simultaneously, and then the flow field is calculated. The former can improve the calculation efficiency, and the latter is closer to the real physical process. Therefore, an appropriate algorithm can be selected according to the needs for single-phase fluid network simulation calculation.

[0054] Step S5: Determine whether to perform water hammer calculation for the single-phase fluid network.

[0055] During the software operation, the parameters of the single-phase fluid network can be modified through the online debugging function. The parameters that can be modified include the streamline length, streamline inner diameter, streamline flow rate, node pressure, node enthalpy value, pump speed on the streamline, valve opening on the streamline, etc. When it is necessary to modify the pump speed and valve opening on the streamline, water hammer calculation for the single-phase fluid network is performed. At this time, additional parameters required for the calculation need to be supplemented, such as pump operating conditions (power-off and pump stop, variable speed), pump inertia, motor electromagnetic torque, valve action time, etc. As Figure 5 shown, the pump at the internal node 4 upstream of streamline 5 is selected for water hammer calculation, the pump inertia is supplemented, and the electromagnetic torque is taken as 0 to simulate the power-off and pump stop case. The online debugging function establishes the coupling between the single-phase fluid network simulation and the single-phase fluid network water hammer simulation, and has strong operability and a good user experience.

[0056] Step S6: Record the thermo-hydraulic state of the single-phase fluid network and perform water hammer initialization for the single-phase fluid network.

[0057] Step S7: Use the wave tracking method to perform water hammer calculation for the single-phase fluid network and update the node pressure and streamline flow rate.

[0058] Steps S6 and S7 are the core steps of the single-phase fluid network water hammer calculation. To improve the efficiency of the single-phase fluid network water hammer calculation, the present invention selects the wave tracking method for water hammer solution. The wave tracking method is a solution method based on the Lagrangian format, which tracks the propagation process of pressure waves in the pipeline and updates the flow field information at the places where the waves pass, and has the advantage of high calculation efficiency. The expression of the wave tracking method:

[0059]

[0060]

[0061] Symbol f represents the downstream wave in the positive direction of flow in the single-phase fluid network topology; symbol F represents the upstream wave in the negative direction of flow in the single-phase fluid network topology; symbol P represents the node pressure; symbol P0 represents the node steady-state pressure; symbol G represents the node mass flow; symbol G0 represents the node steady-state mass flow; symbol a represents the wave speed; symbol A c represents the cross-sectional area of ​​the streamline; the propagation process of water hammer wave in the pipeline is expressed as:

[0062]

[0063]

[0064] The subscripts A and B represent the upstream and downstream nodes on the streamline, respectively; the symbol f A represents the downstream wave at node A; f B represents the downstream wave at node B, symbol L AB represents the streamline length between node A and node B; the symbol ρ represents the streamline density; the symbol J represents the streamline friction loss; the symbol J0 represents the streamline steady-state friction loss.

[0065] From equations (4), (5), (6) and (7), it can be seen that the wave tracking method only needs the node steady-state pressure, streamline flow and geometric parameters of the single-phase fluid network to solve the water hammer. At the same time, it only focuses on the pressure and flow changes at the key nodes, which is similar to the division idea of ​​the node pressure method of the single-phase fluid network simulation. Therefore, the wave tracking method can use the same topological structure with the single-phase fluid network without the need to re-divide the pipe network. Therefore, from the perspective of program writing, the wave tracking method has better program compatibility than other water hammer solution algorithms, can be well coupled with the single-phase fluid network simulation program, and the water hammer calculation efficiency can also be greatly improved.

[0066] S8: Solve the temperature field of the single-phase fluid network and update the thermal state of the node.

[0067] Since the time from the occurrence to the end of the water hammer process is very short, the change in pipeline enthalpy caused by friction during the water hammer process can be basically ignored, so most mathematical models of the water hammer phenomenon do not consider energy changes. However, in thermal systems, energy changes indirectly caused by water hammer need to be considered. For example, water hammer causes fluctuations in the flow rate of the heat transfer pipe, affecting the heat exchange of the heat exchanger, which in turn causes changes in the temperature field in the pipe network. Changes in the temperature field are bound to cause changes in the fluid density, which in turn affects the water hammer calculation. Therefore, the present invention takes into account the impact of temperature field changes on water hammer calculations, improves the accuracy of water hammer solution, and is closer to the real physical process. The temperature field is corrected using the flow network node energy equation (2) to update the node thermal parameters.

[0068] Step S9: Determine whether to continue the water hammer calculation for the single-phase fluid network. The determination basis is the water hammer calculation time given in the online debugging stage. If the water hammer calculation time is reached, the water hammer calculation ends; otherwise, continue the calculation for the next water hammer time step Δt2, and return to Step S7.

[0069] Step S10: Determine whether to continue the single-phase fluid network calculation. The determination basis is the calculation time in the input card. When the calculation time is reached, the calculation ends; otherwise, continue the calculation for the next time step Δt1.

[0070] Figure 6 It is the curve graph of the pump flow rate, pressure, and the temperature change at the condenser outlet during a power failure and pump shutdown accident, and it is from Figure 6 As can be seen from a, when a pump shutdown water hammer occurs, due to the extremely small inertia of the pump and the short coasting time, the pump flow rate drops rapidly and reverses. The reverse flow rate reaches 0.6 kg / s, seriously damaging the pump. As can be seen from Figure 6 b, the maximum pressure is 0.31 MPa, which will have an adverse impact on the pipeline operation. As can be seen from Figure 6 c, after the power failure and pump shutdown, the temperature of the condenser drops rapidly. To sum up, during the operation of the pipe network, the occurrence of pump shutdown water hammer should be avoided, or the impact of water hammer can be alleviated by increasing the inertia of the pump. From this example, it can be seen that the present invention can well simulate the fluctuations of temperature, pressure, and flow rate when a power failure and pump shutdown accident occurs in the thermal system.

[0071] The present invention uses the form of an input card to input the data required for the single-phase fluid network simulation calculation, making the data input simple and standardized, and improving the program usage efficiency. By identifying whether to perform the water hammer calculation for the single-phase fluid network during the online debugging stage and supplementing the water hammer calculation data through the online window, the coupling between the single-phase fluid network simulation and the single-phase fluid network water hammer simulation is realized, and the independence between the two is strong. The present invention uses the wave tracking method for water hammer calculation. Compared with other solution methods, the water hammer calculation efficiency is greatly improved. During the single-phase fluid network water hammer calculation, the influence of the temperature field change on the water hammer calculation is considered, improving the solution accuracy and being closer to the real physical process. A single-phase fluid network water hammer process simulation method proposed by the present invention makes up for the deficiency that the single-phase fluid network simulation cannot perform the water hammer process simulation, and expands the application scope of the single-phase fluid network simulation.

[0072] Those of ordinary skill in the art can understand that: The drawings are only schematic diagrams of an embodiment, and the modules or processes in the drawings are not necessarily essential for implementing the present invention.

[0073] Those of ordinary skill in the art can understand that the modules in the device in the embodiments can be distributed in the device in the embodiments as described, or can be correspondingly changed to be located in one or more devices different from the present embodiments. The modules in the above embodiments can be combined into one module, or can be further split into multiple sub-modules.

[0074] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some of the technical features. And these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A simulation method for the water hammer process in a single-phase fluid network, characterized in that, Including: Step S1: Divide nodes and streamlines based on the network characteristics of the pipe network system composed of a condenser, a pump, and a pressure vessel, and fill in the input card. Step S2: Read the data in the input card and initialize the single-phase fluid network simulation calculation. Step S3: Select a single-phase fluid network algorithm to calculate the node pressure, enthalpy value, and streamline flow rate; update the thermal-hydraulic state of the nodes and streamlines, and output key parameters. Specifically, it includes: List the single-phase fluid network mathematical model shown in the following formula: Equation (1) is the node mass conservation equation, Equation (2) is the node energy conservation equation, and Equation (3) is the streamline momentum conservation equation. In the equations, the symbol V represents the volume of the node; the symbol ρ represents the density of the node; the symbol D represents the incidence matrix between nodes, D ij = 1 indicates flow from node j to node i, D ij = 0 indicates no connection between node i and node j, D ij = -1 indicates flow from node i to node j; the symbol G represents the flow value between nodes; the symbol Y represents the value range of the node number as [1, Y]; the symbol M represents the mass of the node; the symbol P represents the pressure of the node; the symbol v represents the specific volume of the node; the symbol G in represents the flow rate into node i; the symbol G out represents the flow rate out of node i; the symbol h represents the specific enthalpy value of the node; the symbol K represents the heat transfer coefficient between the node and the environment; the symbol A h represents the heat transfer area between the node and the environment; the symbol T represents the node temperature; the symbol T0 represents the environmental temperature; the symbol Q represents the heat absorption or internal heat source of the node; the symbol W represents the work done by the node; the symbol L represents the streamline length; the symbol A represents the flow cross-sectional area of the streamline; the symbol Hpump represents the head of the pump on the streamline; the symbol Hg represents the gravity pressure difference on the streamline; the symbol f represents the frictional pressure drop and local pressure drop on the streamline; Step S4: Determine whether to perform single-phase fluid network water hammer calculation. Step S5: Record the thermal-hydraulic state of the single-phase fluid network and initialize the single-phase fluid network water hammer. Step S6: Use the wave tracking method to perform single-phase fluid network water hammer calculation and update the node pressure and streamline flow rate. Step S7: Solve the temperature field of the single-phase fluid network and update the thermal state of the nodes. Step S8: Determine whether to continue the single-phase fluid network water hammer calculation. The judgment basis is the water hammer calculation time given in the on-line commissioning stage. If the water hammer calculation time is reached, the water hammer calculation is ended; otherwise, continue to calculate the next water hammer time step Δt2, and return to Step S6. Step S9: Determine whether to continue the single-phase fluid network calculation. The judgment basis is the calculation time in the input card. When the calculation time is reached, the calculation is ended; otherwise, continue to calculate the next time step Δt1.

2. The simulation method for the water hammer process in a single-phase fluid network according to claim 1, characterized in that, The input card includes a flow network quantity card, a calculation card, a pressure boundary data card, a flow rate boundary data card, an internal node data card, a streamline data card, a pump data card, and a hot plate data card.

3. The simulation method for the water hammer process in a single-phase fluid network according to claim 2, characterized in that, The calculation card includes the type of calculation, the start time of calculation, the calculation step, the end time of calculation, and the fluid type; the pressure boundary data card includes the pressure and enthalpy value of the pressure boundary node; the flow rate boundary data card includes the flow rate and enthalpy value of the flow rate boundary node; the internal node data card includes the pressure, flow rate, and enthalpy value of the internal node. The internal node data card is used as the initial data, and the data of the flow rate boundary node and the pressure boundary node are used as the boundary conditions; the streamline data card includes the topological structure between nodes and the streamline geometric parameters; the pump data card includes the rated parameters of the pump; the hot plate data card includes the geometric parameters of the hot plate, the heat transfer coefficient, and the node connection relationship.

4. The simulation method for the water hammer process in a single-phase fluid network according to claim 1, characterized in that, Steps S5 and S6 specifically include: Select the wave tracking method to solve the water hammer. The expression of the wave tracking method is as follows: Among them, the symbol f represents the downstream wave in the positive direction of the flow rate in the single-phase fluid network topology; the symbol F represents the upstream wave in the negative direction of the flow rate in the single-phase fluid network topology; the symbol P represents the node pressure; the symbol P0 represents the node steady-state pressure; the symbol G represents the node mass flow rate; the symbol G0 represents the node steady-state mass flow rate; the symbol a represents the wave speed; the symbol A c represents the cross-sectional area of the streamline; the expression for the propagation process of the water hammer wave in the pipeline is: where the subscripts A and B represent the upstream and downstream nodes on the streamline respectively; the symbol f A represents the downstream wave at node A; f B represents the downstream wave at node B, and the symbol L AB represents the streamline length between node A and node B; the symbol ρ represents the streamline density; the symbol J represents the streamline friction loss; the symbol J0 represents the streamline steady-state friction loss.

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