Modeling method, system and equipment for nuclear energy heat supply system and medium

Abstract

The invention relates to the field of nuclear energy system simulation, in particular to a modeling method, system, equipment and medium for a nuclear energy heat supply system, which comprises the following steps: according to the topological structure of the nuclear energy heat supply system, the action of each equipment in the conversion process of nuclear energy and heat energy, the component and interface structure in each equipment, and the component and interface structure in each equipment; decomposing the data into subsystems, equipment, components, basic equations and basic physical elements; establishing corresponding basic models for the basic equations and the basic physical elements, and establishing corresponding component models, equipment models and subsystem models for the components, the equipment and the subsystems; and according to the topological structure, coupling the basic model, the component model, the equipment model and the subsystem model to construct a simulation model of the nuclear energy heat supply system. Based on the unified modeling language, interface adaptation work caused by interface incompatibility in an existing method is avoided, the modeling process is greatly simplified, and the modeling simulation efficiency of the nuclear energy heat supply system is improved.

Description

Technical Field

[0001] The present invention relates to the field of nuclear energy system simulation, and in particular to a modeling method, system, equipment and medium for a nuclear energy heating system. Background Art

[0002] Nuclear energy heating system is a heating system that uses nuclear energy as a heat source. Among them, low-temperature heating reactor system is a special form of nuclear energy heating system, which is mainly used for low-temperature heating, such as heating and industrial heating. Since these systems have complex nonlinear characteristics with multiple variables and strong coupling, and cover multiple professional fields such as nuclear reactor physics, thermal engineering, fluid, control, and electrical engineering, modeling and simulation technology plays a vital role in the design, analysis, and optimization of these systems. Through modeling and simulation, the behavior of the system can be studied and understood in a virtual environment, thereby improving the performance and reliability of the system, while reducing the risk and cost of experiments and development.

[0003] In the current nuclear heating system modeling and simulation technology, the interface-based multi-tool joint simulation technology is widely used. This technology links various professional models together to form a joint simulation environment, thereby realizing multi-professional system modeling and simulation. However, since the interface standards of various tools are usually different, the interface of this method lacks standardization and openness, and a lot of interface adaptation work is required, which greatly increases the complexity and workload of modeling work. Summary of the invention

[0004] In order to solve the above problems, the present invention provides a modeling method, system, equipment and medium for a nuclear energy heating system.

[0005] The first aspect of the present invention discloses a modeling method for a nuclear energy heating system, comprising:

[0006] According to the topological structure of the nuclear energy heating system, the role of each device in the nuclear energy heating system in the conversion process between nuclear energy and thermal energy, and the components and interface structures in each device, the nuclear energy heating system is decomposed layer by layer from top to bottom into subsystems, devices, components, basic equations and basic physical elements;

[0007] Based on the Modelica modeling language, corresponding basic models are established for the basic equations and basic physical elements, and corresponding component models, device models and subsystem models are established for the components, the devices and the subsystems;

[0008] Based on the Modelica modeling language and according to the topological structure, a plurality of subsystem models are coupled and combined with the basic model to construct a simulation model of the nuclear energy heating system.

[0009] Further, the steps of decomposing the nuclear energy heating system layer by layer from top to bottom into subsystems, devices, components, basic equations, and basic physical elements according to the topological structure of the nuclear energy heating system, the role of each device in the nuclear energy - thermal energy conversion process in the nuclear energy heating system, and the components and interface structures in each device include:

[0010] Decompose the topological structure of the nuclear energy heating system to obtain multiple subsystems, and determine the connection relationships between the multiple subsystems;

[0011] Decompose each subsystem according to the system process to obtain multiple devices and multiple components, and determine the connection relationships between devices, between components, and between devices and components;

[0012] Decompose each device according to the device structure to obtain multiple components and multiple basic equations;

[0013] Extract the basic physical elements of each component.

[0014] Further, the steps of establishing corresponding basic models for the basic equations and basic physical elements, and establishing corresponding component models, device models, and subsystem models for the components, devices, and subsystems based on the Modelica modeling language include:

[0015] Based on the Modelica modeling language, construct the basic model according to the basic equations and basic physical elements;

[0016] Create the component model based on the basic model according to the component;

[0017] Create the device model based on the basic model and the component model according to the device;

[0018] Create the subsystem model based on the basic model, the component model, and the device model according to the subsystem.

[0019] Further, the basic equations include: the point - reactor neutron kinetics model related to the heating system, the nodal neutron kinetics model, the reactivity model, the decay heat model, the iodine - xenon kinetics model, the homogeneous flow three - equation related to the fluid, the two - fluid five - equation, the valve and / or pump characteristic curve, the inertial cavity equation, the two - region non - equilibrium equation, the pressure drop, the heat transfer coefficient, and the Fourier heat conduction equation related to the pipe and / or cavity geometry and / or heat conduction;

[0020] The basic physical elements include: physical property media, interfaces, functions, units, icons, and / or boundary conditions.

[0021] Further, the component model includes a pipeline model, a cavity model, a valve model, a pump model, a heat component model, a fuel rod model, and / or a component control model.

[0022] Further, the steps of constructing the component model based on the basic model include:

[0023] Construct the component models of multiple different components;

[0024] Select the basic model corresponding to each component model;

[0025] Associate the selected basic model with the component model.

[0026] Further, the steps of constructing the equipment model based on the basic model and the component model include:

[0027] Construct the equipment models of multiple different equipment;

[0028] Select the component model and the basic model corresponding to each equipment model;

[0029] Associate the selected component model and the basic model with the corresponding equipment model.

[0030] Further, the equipment model includes a nuclear island equipment model and / or a conventional island equipment model, wherein the nuclear island equipment model includes: a reactor core, a main heat exchanger, a steam generator, and / or a pressurizer; the conventional island equipment model includes a condenser, a shell-and-tube heat exchanger, a deaerator, and / or an air cooler.

[0031] Further, the steps of building the subsystem model based on the basic model, the component model, and the equipment model include:

[0032] Establish multiple different subsystem models according to the different functions of the heating system;

[0033] Select the component model, the basic model, and the equipment model corresponding to each subsystem model;

[0034] Associate the selected component model, the basic model, and the equipment model with the corresponding subsystem model.

[0035] Further, the subsystem model includes: a coolant subsystem, an intermediate loop subsystem, a secondary loop steam subsystem, a feedwater subsystem, a steam generator blowdown subsystem, a residual heat removal subsystem, a safety relief subsystem, a boron injection subsystem, a reactor power control subsystem, and / or a nuclear reactor protection subsystem.

[0036] The second aspect of the present invention discloses a modeling system for a nuclear energy heating system, comprising:

[0037] A decomposition module, for decomposing the nuclear energy heating system from top to bottom into subsystems, devices, components, basic equations and basic physical elements according to the topological structure of the nuclear energy heating system, the role of each device in the nuclear energy and thermal energy conversion process, and the components and interface structures in each device;

[0038] A first building module is used to establish corresponding basic models, component models, device models and subsystem models for the basic equations and basic physical elements, the components, the devices and the subsystems based on the Modelica modeling language;

[0039] The second construction module is used to couple the basic model, the component model, the equipment model and the subsystem model based on the Modelica modeling language and according to the topology structure to construct a simulation model of the nuclear energy heating system.

[0040] The third aspect of the present invention discloses an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the modeling method of the nuclear energy heating system as described in any one of the first aspect of the present invention when executing the computer program.

[0041] The fourth aspect of the present invention discloses a storage medium storing a computer program, wherein the computer program, when executed by a processor, implements the steps of the modeling method of a nuclear energy heating system as described in any one of the first aspect of the present invention.

[0042] The present invention is based on a unified modeling language, avoids the interface adaptation work caused by interface incompatibility in the existing method, greatly simplifies the modeling process, and improves the efficiency of modeling and simulation of the nuclear energy heating system. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0044] Figure 1 It is a flow chart of a modeling method of a nuclear energy heating system disclosed in an embodiment of the present invention;

[0045] Figure 2 is a decomposed structural diagram of a low-temperature heating reactor system disclosed in an embodiment of the present invention;

[0046] Figure 3 is the four - level model of the low - temperature heat - supply reactor system disclosed in the embodiments of the present invention;

[0047] Figure 4 (a) is the nuclear reactor power calculated by the simulation model constructed for the low - temperature heat - supply reactor system disclosed in the embodiments of the present invention;

[0048] Figure 4 (b) is the coolant outlet temperature calculated by the simulation model constructed for the low - temperature heat - supply reactor system disclosed in the embodiments of the present invention;

[0049] Figure 4 (c) is the coolant flow rate calculated by the simulation model constructed for the low - temperature heat - supply reactor system disclosed in the embodiments of the present invention;

[0050] Figure 4 (d) is the steam supply flow rate given by the simulation model constructed for the low - temperature heat - supply reactor system disclosed in the embodiments of the present invention;

[0051] Figure 4 (e) is the steam flow rate calculated by the simulation model constructed for the low - temperature heat - supply reactor system disclosed in the embodiments of the present invention;

[0052] Figure 4 (f) is the feed - water flow rate calculated by the simulation model constructed for the low - temperature heat - supply reactor system disclosed in the embodiments of the present invention;

[0053] Figure 5 is the structural schematic diagram of a modeling system for a nuclear energy heat - supply system disclosed in the embodiments of the present invention;

[0054] Figure 6 is the structural schematic diagram of an electronic device disclosed in the embodiments of the present invention. Detailed implementation manners

[0055] In order to enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts fall within the scope of protection of the present invention.

[0056] In the description, claims and above-mentioned drawings of the present invention, terms such as "first", "second", etc. are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "comprise" and "have" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, device, or product end that includes a series of steps or units is not limited to the listed steps or units, but optionally further includes steps or units not listed, or optionally further includes other steps or units inherent to these processes, methods, products, or ends.

[0057] Reference to "embodiment" herein means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the present invention. The phrase appears in various places in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0058] As a multi-domain unified modeling language prevailing in the current industrial community, Modelica has the characteristics of equation-based, object-oriented, hierarchical, and extensible. Model developers only need to focus on physical phenomena without concerning about the solution process, which provides great convenience for model developers. At the same time, since Modelica is an open physical modeling language, the developed models have independent intellectual property rights, which can effectively avoid technical constraints caused by external factors.

[0059] Develop an integrated simulation model library covering multiple specialties such as nuclear reactor physics, thermal engineering, fluid, and control based on the Modelica multi-domain unified modeling language, and adopt the same model description form to achieve the integrated integration between different professional subsystem models involved in the nuclear energy heating system; construct a basic model for providing the basic equations and related support functions required for component model and equipment model modeling, a component model for providing the basic components required for constructing equipment models and component subsystem models, an equipment model for nuclear energy heating system equipment modeling, and a subsystem model required for subsystem modeling.

[0060] In the present invention, the nuclear energy heating system refers to a low-temperature heating reactor system, which is a type of nuclear energy heating system that uses the low-temperature heat generated by a nuclear reactor to provide heating and industrial steam for residential areas, industrial parks, etc. The system consists of a nuclear reactor, heat exchangers, circulation pumps, steam generators, pipeline networks, etc. The heat generated by the nuclear reactor is transferred by the coolant to the intermediate loop through the heat exchanger, and then transferred to the steam system on the secondary side through the steam generator in the intermediate loop, and then transported to the user end through the pipeline network. Compared with traditional high-temperature nuclear reactors, the low-temperature heating reactor has a lower working pressure and an integrated layout on the nuclear side, with inherent safety, and this low-temperature heating reactor is more suitable for meeting the needs of providing heating and industrial steam. The low-temperature heating reactor system has the advantages of high safety, small environmental impact, high energy utilization efficiency, etc., and is a promising clean heating method.

[0061] The low-temperature heating reactor system is a multi-variable, strongly coupled complex non-linear system containing many functional modules, and its modeling and simulation scope covers multiple professional fields such as nuclear reactor physics, thermal engineering, fluid, control, and electrical. Taking the low-temperature heating reactor system as an example, the present invention specifically explains how to construct a simulation model of the nuclear energy heating system.

[0062] Please refer to Figure 1 as shown Figure 1 is a schematic flow chart of a modeling method for a nuclear energy heating system disclosed in an embodiment of the present invention. As Figure 1 shown, the modeling method for the nuclear energy heating system may include the following operations:

[0063] S101. According to the topological structure of the nuclear energy heating system, the role of each device in the nuclear energy and thermal energy conversion process of the nuclear energy heating system, and the components and interface structures in each device, decompose the nuclear energy heating system layer by layer from top to bottom into subsystems, devices, components, basic equations, and basic physical elements;

[0064] In an optional embodiment, the step of decomposing the nuclear energy heating system layer by layer from top to bottom into subsystems, devices, components, basic equations, and basic physical elements according to the topological structure of the nuclear energy heating system, the role of each device in the nuclear energy and thermal energy conversion process of the nuclear energy heating system, and the components and interface structures in each device includes:

[0065] Decompose the topological structure of the nuclear energy heating system to obtain a plurality of the subsystems, and determine the connection relationships between the plurality of subsystems;

[0066] Decompose each subsystem according to the system process to obtain a plurality of the devices and a plurality of the components, and determine the connection relationships between the devices, between the components, and between the devices and the components;

[0067] Decompose each of the said devices according to the device structure to obtain a plurality of the said components and a plurality of the said basic equations;

[0068] Extract the basic physical elements of each of the said components.

[0069] In this alternative embodiment, the basic equations refer to the basic physical or chemical equations that describe the working principles and performance of the devices or components, and the basic physical elements refer to the elements that describe the physical behavior or performance of the components according to the principles of physics.

[0070] In this alternative embodiment, the topological structure refers to the connection and interaction modes of each device or component in the nuclear energy heating system, which depicts the overall structure of the nuclear energy heating system and the mutual relationship between its various parts. The conversion process of nuclear energy and heat energy refers to the process in which the energy released during the nuclear reaction is converted into heat energy. In the nuclear energy heating system, a large amount of heat is generated during the nuclear reaction, and this part of the heat can be exported by the medium and used for heating. The basic physical processes refer to the basic physical changes that occur at the component level, such as heat exchange, fluid flow, etc. The basic equations refer to the mathematical equations that describe the basic physical processes, such as the energy conservation equation, etc., and these equations can describe and simulate the working process of the nuclear energy heating system.

[0071] Figure 2 Shows the decomposition structure diagram of the nuclear energy heating system, where the coolant subsystem, the control subsystem, and the protection subsystem are subsystems, and the nuclear reactor core, the main heat exchanger, and the pressurizer are devices. Figure 2 On the left side of the bottom layer in it are components, and on the right side are basic equations and basic physical elements.

[0072] S102. Based on the Modelica modeling language, establish corresponding basic models for the basic equations and basic physical elements, and establish corresponding component models, device models, and subsystem models for the components, the devices, and the subsystems;

[0073] Please refer to Figure 3 , Figure 3 Shows the four-level model of the nuclear energy heating system.

[0074] In an alternative embodiment, the step of establishing corresponding basic models for the basic equations and basic physical elements, and establishing corresponding component models, device models, and subsystem models for the components, the devices, and the subsystems based on the Modelica modeling language includes:

[0075] Based on the Modelica modeling language, construct the basic models according to the basic equations and basic physical elements;

[0076] Create the component models according to the components based on the basic models;

[0077] Create a device model based on the basic model and component model according to the device.

[0078] Create the subsystem model based on the basic model, the component model, and the device model according to the subsystem.

[0079] In a further optional embodiment, the basic equations include: the point kinetics neutron dynamics model related to the heating system, the nodal neutron dynamics model, the reactivity model, the decay heat model, the iodine-xenon kinetics model, the homogeneous flow three-equation related to the fluid, the two-fluid five-equation, the valve and / or pump characteristic curve, the inertia cavity equation, the two-region non-equilibrium equation, the pressure drop, the heat transfer coefficient, and the pipe and / or cavity geometry and / or the Fourier heat conduction equation related to heat conduction;

[0080] The basic physical elements include: physical property media, interfaces, functions, units, icons, and / or boundary conditions.

[0081] In this optional embodiment, the point kinetics neutron dynamics model, the nodal neutron dynamics model, the reactivity model, the decay heat model, and the iodine-xenon kinetics model are all models describing the internal processes of a nuclear reactor. For example, the point kinetics neutron dynamics model and the nodal neutron dynamics model describe the distribution and movement of neutrons in the reactor, the reactivity model describes how the reactivity of the reactor changes over time, the decay heat model describes the heat generated due to radioactive decay, and the iodine-xenon kinetics model describes the behavior of iodine and xenon in the reactor.

[0082] The homogeneous flow three-equation, the two-fluid five-equation, the valve and / or pump characteristic curve, the inertia cavity equation, the two-region non-equilibrium equation, the pressure drop, the heat transfer coefficient, and the pipe and / or cavity geometry are all models and data describing hydrodynamic and thermodynamic processes. For example, the homogeneous flow three-equation and the two-fluid five-equation describe the motion state of the fluid. The valve and / or pump characteristic curve describes the performance of the valve and pump. The inertia cavity equation describes the motion of the fluid in the cavity. The two-region non-equilibrium equation describes the mass and energy exchange of the fluid between the vapor and liquid regions. The pressure drop, the heat transfer coefficient, and the pipe and / or cavity geometry provide relevant physical parameters.

[0083] Physical property media, interfaces, functions, units, icons, and / or boundary conditions are all basic elements to be considered when building a model. Physical property media describe the properties of substances, such as density, viscosity, etc. Interfaces describe the connection methods between components and the relevant parameters transmitted. Functions are used to implement specific calculations. Units are used to quantify physical quantities. Icons are used to represent the graphical presentation of the model. Boundary conditions are the conditions that need to be given when solving physical equations.

[0084] In an alternative embodiment, the steps of constructing the component model based on the basic model include:

[0085] Construct the component models of multiple different components;

[0086] Select the basic model corresponding to each of the component models;

[0087] Associate the selected basic model with the component model.

[0088] In an alternative embodiment, the component model includes a pipeline model, a cavity model, a valve model, a pump model, a heat component model, a fuel rod model, and / or a component control model.

[0089] In a nuclear heating system, the pipeline model describes the one-dimensional flow process of fluid in the pipeline of the nuclear heating system to predict the behavior of the fluid in the pipeline.

[0090] The cavity model describes the sealed or open containers in the nuclear heating system, such as the upper space of the reactor pressure vessel, etc. The main function of these cavities in the nuclear heating system is to mix or separate fluids. The cavity model can be used to simulate the situation of fluid separation or mixing in the system.

[0091] The valve model describes the valves used to regulate or control the fluid flow in the nuclear heating system, which are used to regulate or control the fluid flow. The valve model can be used to simulate regulating valves, check valves, globe valves, three-way valves, etc. in the nuclear heating system. Pumps are mainly used to drive the coolant to flow in the system, and the pump model can be used to simulate centrifugal pumps, axial flow pumps, etc. in the nuclear heating system.

[0092] The heat component model describes the walls with heat exchange in the nuclear heating system, such as the tube wall of a shell-and-tube heat exchanger, etc. The main function of the heat component in the system is to transfer heat, and it can be used to simulate the heat transfer walls of various heat exchange devices.

[0093] The fuel rod model describes the heat exchange structure between the pellets, gaps, and claddings of the nuclear fuel rods in the nuclear heating system, which can be understood as a heat component composed of three different physical property heat components. The fuel rod model can be used to simulate the process of the fission energy and / or decay energy in the reactor core being transferred from the fuel pellets to the coolant.

[0094] The component control model describes the control system used to control the working states of various devices in the nuclear heating system. In the system, the control system is a key part to ensure the normal operation and safety of the system. The component control model can be used to simulate and emulate the working performance of the control system.

[0095] In an alternative embodiment, the steps of constructing the device model based on the basic model and the component model include:

[0096] Establish the device models of multiple different devices;

[0097] Select the component models and the basic models corresponding to each of the device models;

[0098] Associate the selected component models and basic models with the corresponding device models.

[0099] In an alternative embodiment, the device models include nuclear island device models and / or conventional island device models, wherein the nuclear island device models include: reactor core, main heat exchanger, steam generator and / or pressurizer; the conventional island device models include condenser, shell-and-tube heat exchanger, deaerator and / or air cooler.

[0100] In this alternative embodiment, nuclear island devices include all devices related to nuclear reactions and radioactive substances, such as reactor core, pressurizer, etc. Conventional island devices include all non-radioactive devices, such as shell-and-tube heat exchanger, deaerator, air cooler, etc. The reactor core is the main part of a nuclear reactor, which contains fuel rods and coolant flow channels surrounding them, and is the place where nuclear reactions occur to release heat and the heat is carried out by the coolant. The pressurizer is a device used to regulate and stabilize the system pressure to ensure the normal operation of the system. The shell-and-tube heat exchanger is a common heat exchange device used for heat exchange between two fluids. The deaerator is mainly used to remove oxygen in the feed water of the steam generator to prevent corrosion. The air cooler is a cooling device used to cool the fluid through air and reduce its fluid temperature.

[0101] In an alternative embodiment, the steps of building the subsystem model based on the basic model, the component model and the device model include:

[0102] Establish multiple different subsystem models according to different functions of the heating system;

[0103] Select the component models, the basic models and the device models corresponding to each of the subsystem models;

[0104] Associate the selected component models, basic models and device models with the corresponding subsystem-level models.

[0105] In an alternative embodiment, the subsystem models include: coolant subsystem, intermediate loop subsystem, secondary loop steam subsystem, feed water subsystem, steam generator blowdown subsystem, residual heat removal subsystem, safety relief subsystem, boron injection subsystem, reactor power control subsystem and / or nuclear reactor protection subsystem.

[0106] In this optional embodiment, the coolant subsystem transfers heat from the reactor core to the main heat exchanger, and then recirculates the coolant back to the core. Its main function is to cool the core and transfer heat to the intermediate loop subsystem. The intermediate loop subsystem serves as a "bridge" between the main coolant and the secondary loop steam subsystem. Its purpose is to transfer heat to the secondary loop steam subsystem while keeping the radioactive materials in the nuclear island. The secondary loop steam subsystem is mainly responsible for receiving heat from the intermediate loop subsystem and generating steam for heating. The water supply subsystem is responsible for providing deoxygenated water of a certain temperature and pressure to the steam generator for generating steam in the secondary loop steam subsystem. The steam generator sewage subsystem is responsible for treating and managing the sewage generated by the steam generator to keep the system clean and efficient. The residual heat removal subsystem is responsible for exporting the residual heat of the core during or after the shutdown process to maintain the safety and stability of the system. The safety relief subsystem is responsible for safely venting the pressure of the coolant subsystem when the pressure of the coolant subsystem is too high to prevent the system from overpressure. The boron injection subsystem is responsible for injecting boron solution into the coolant to control the reactivity of the reactor. The reactor power control subsystem is responsible for adjusting the reactor power output according to the system requirements. The nuclear reactor protection subsystem is responsible for monitoring the operating status of the reactor and automatically taking measures to protect the safety of the reactor and the system when an abnormality is detected.

[0107] S103. Based on the Modelica modeling language and according to the topological structure, the basic model, the component model, the equipment model and the subsystem model are coupled and combined to construct a simulation model of the nuclear energy heating system.

[0108] Please refer to Figure 4 , Figure 4 It is a simulation model built for a low temperature heating reactor system based on the modeling method provided by the present invention, and the dynamic response results of key parameters under the 100% FP-90% FP-100% FP step change load condition are obtained by simulation. Figure 4 (a) is the curve of nuclear reactor power changing with time. Figure 4 (b) is the curve of the coolant outlet temperature changing with time. Figure 4 (c) is the curve of coolant flow rate changing with time, Figure 4 (d) is the curve of steam flow rate changing with time. Figure 4 (e) is the curve of steam flow rate changing with time, Figure 4(f) is the curve of feedwater flow rate changing with time. The load is characterized by steam supply flow rate, and variable load means that the steam supply flow rate changes according to the set curve. During the step load reduction process, the steam supply flow rate changes according to the set curve by adjusting the steam valve opening on the steam supply flow branch. Affected by the change in the steam supply valve opening, the steam flow rate also decreases accordingly. In order to maintain a constant liquid level in the steam generator, the feedwater flow set value is reduced during the step load reduction process, and the feedwater valve opening will be reduced to reduce the flow through the feedwater valve. The reduction in feedwater flow leads to a decrease in the heat taken away by the feedwater side of the intermediate loop, and then the heat generated in the reactor accumulates and causes the coolant outlet temperature to increase. Under the action of the nuclear reactor power control system, reactivity is introduced into the reactor to reduce the power of the nuclear reactor. At the same time, because the coolant system operates in a natural circulation mode, the reduction in nuclear reactor power leads to a decrease in the pressure head provided by the density difference, which in turn leads to a decrease in coolant flow. When the load is stepped up, the trend is exactly the opposite of the step load reduction.

[0109] like Figure 5 As shown, the present invention provides a modeling system for a nuclear energy heating system, comprising:

[0110] A decomposition module 501 is used to decompose the nuclear energy heating system from top to bottom into subsystems, devices, components, basic equations and basic physical elements according to the topological structure of the nuclear energy heating system, the role of each device in the nuclear energy and thermal energy conversion process, and the components and interface structure in each device.

[0111] A first construction module 502 is used to establish corresponding basic models for the basic equations and basic physical elements, and to establish corresponding component models, device models and subsystem models for the components, devices and subsystems;

[0112] The second construction module 503 is used to couple the multiple subsystem models based on the Modelica modeling language and according to the topological structure, and combine them with the basic model to construct a simulation model of the nuclear energy heating system.

[0113] The specific definition of the modeling system of the nuclear energy heating system can be found in the definition of the modeling method of the nuclear energy heating system mentioned above, which will not be repeated here. Each module in the above-mentioned modeling system of the nuclear energy heating system can be implemented in whole or in part by software, hardware and a combination thereof. The above-mentioned modules can be embedded in or independent of the processor in the electronic device in hardware format, or can be stored in the memory of the electronic device in software format, so that the processor can call the operations corresponding to the above modules.

[0114] It should be noted that, in order to highlight the innovative part of the present invention, modules that are not closely related to solving the technical problems proposed by the present invention are not introduced in this embodiment, but this does not mean that there are no other modules in this embodiment.

[0115] As Figure 6 described, the electronic device 1 provided by the present invention may include a memory 12, a processor 13 and a bus, and may also include a computer program stored in the memory 12 and executable on the processor 13, such as a modeling program for a nuclear energy heating system.

[0116] Among them, the memory 12 includes at least one type of readable storage medium, and the readable storage medium includes flash memory, mobile hard disk, multimedia card, card-type memory (such as: SD or DX memory, etc.), magnetic memory, magnetic disk, optical disk, etc. The memory 12 may be an internal storage unit of the electronic device 1 in some embodiments, such as the mobile hard disk of the electronic device 1. The memory 12 may also be an external storage device of the electronic device 1 in other embodiments, such as a plug-in mobile hard disk, a Smart Media Card (SMC), a Secure Digital (SD) card, a Flash Card, etc. equipped on the electronic device 1. Further, the memory 12 may also include both an internal storage unit and an external storage device of the electronic device 1. The memory 12 can not only be used to store application software installed in the electronic device 1 and various types of data, such as the code for modeling a nuclear energy heating system, etc., but also be used to temporarily store data that has been output or will be output.

[0117] The processor 13 may be composed of integrated circuits in some embodiments. For example, it may be composed of a single packaged integrated circuit, or may be composed of multiple integrated circuits with the same or different functions, including a combination of one or more central processing units (CPUs), microprocessors, digital processing chips, graphics processors, and various control chips, etc. The processor 13 is the control core (Control Unit) of the electronic device 1, connecting various components of the entire electronic device 1 through various interfaces and lines, and by running or executing programs or modules stored in the memory 12 (such as a modeling program for a nuclear energy heating system, etc.), and calling data stored in the memory 12, to execute various functions of the electronic device 1 and process data.

[0118] The processor 13 executes the operating system of the electronic device 1 and various installed application programs. The processor 13 executes the application program to implement the steps in the above-mentioned modeling method for a nuclear energy heating system.

[0119] Exemplarily, the computer program may be divided into one or more modules, which are stored in the memory 12 and executed by the processor 13 to complete the present application. The one or more modules may be a series of computer program instruction segments capable of performing specific functions, and these instruction segments are used to describe the execution process of the computer program in the electronic device 1. For example, the computer program may be divided into a decomposition module 501, a first construction module 502, and a second construction module 503.

[0120] The integrated unit implemented in the form of a software functional module as described above may be stored in a computer-readable storage medium, and the storage medium may be non-volatile or volatile. The above-mentioned software functional module is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a computer device, or a network device, etc.) or a processor to execute some functions of the nuclear energy heating system modeling method according to various embodiments of the present application.

[0121] In one embodiment, a storage medium is provided, on which a computer program is stored, and when the computer program is executed by a processor, the steps implemented when the processor executes the computer program may also be realized.

[0122] It can be seen that the multi-disciplinary unified modeling and simulation method for nuclear energy heating systems based on Modelica is developed using the multi-domain unified modeling language Modelica. Applying the object-oriented concept, a model is constructed using a hierarchical mechanism, a component connection mechanism, and an inheritance mechanism, which simplifies the model structure. This modeling method combines the actual physical topology of the nuclear energy heating system, unifies the modeling and simulation of multiple professional systems involved in the nuclear energy heating system, such as nuclear reactor physics, fluid, thermal engineering, and control, and the simulation model view has a similar structural hierarchy and layout to the actual physical system.

[0123] The multi-disciplinary unified modeling and simulation method for nuclear energy heating systems based on Modelica divides the nuclear energy heating system into subsystem models, equipment models, component models, and basic models using a top-down hierarchical decomposition method. Then, the models at each level are analyzed and summarized to form the overall architecture of the model library. Subsequently, development and integration are achieved layer by layer in a bottom-up manner. When constructing the simulation model of the nuclear energy heating system based on this hierarchical model, drag-and-drop modeling can be performed. The basic models and component models are integrated into equipment models according to the topological structure of the system. Then, subsystem models are constructed based on the component models and equipment models, and a multi-disciplinary system simulation model is constructed based on the subsystem models. A multi-disciplinary coupled system model is constructed through a hierarchical modeling method. On this basis, modular, parametric, visual, and multi-physical field coupled rapid dynamic modeling and simulation of the nuclear energy heating system based on the Modelica unified modeling language can be realized. Moreover, since each professional system is constructed based on the unified modeling language, the solution efficiency and accuracy are high during the simulation stage.

[0124] The above embodiments are only illustrative of the principles and effects of the present invention and are not intended to limit the present invention. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical ideas disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A modeling method for a nuclear energy heating system, characterized in that: The method comprises: According to the topological structure of the nuclear energy heating system, the role of each device in the nuclear energy heating system in the conversion process between nuclear energy and thermal energy, and the components and interface structures in each device, the nuclear energy heating system is decomposed layer by layer from top to bottom into subsystems, devices, components, basic equations and basic physical elements; Based on the Modelica modeling language, corresponding basic models are established for the basic equations and basic physical elements, and corresponding component models, device models and subsystem models are established for the components, the devices and the subsystems; Based on the Modelica modeling language and according to the topological structure, a plurality of subsystem models are coupled and combined with the basic model to construct a simulation model of the nuclear energy heating system.

2. A modeling method for a nuclear energy heating system according to claim 1, characterized in that: According to the topological structure of the nuclear energy heating system, the role of each device in the nuclear energy heating system in the conversion process between nuclear energy and thermal energy, and the components and interface structure in each device, the steps of decomposing the nuclear energy heating system layer by layer from top to bottom into subsystems, devices, components, basic equations and basic physical elements include: Decomposing the topological structure of the nuclear energy heating system to obtain a plurality of subsystems, and determining the connection relationship between the plurality of subsystems; Decomposing each of the subsystems according to the system flow to obtain a plurality of the devices and a plurality of the components, and determining connection relationships between the devices, between the components, and between the devices and the components; Decomposing each of the devices according to the device structure to obtain a plurality of the components and a plurality of the basic equations; The underlying physical elements of each of the components are extracted.

3. A modeling method for a nuclear energy heating system according to any one of claim 2, characterized in that: The steps of establishing corresponding basic models for the basic equations and basic physical elements, and establishing corresponding component models, device models and subsystem models for the components, the devices and the subsystems based on the Modelica modeling language include: Based on the Modelica modeling language, construct the basic model according to the basic equations and basic physical elements; According to the component, creating the component model based on the basic model; According to the device, creating a device model based on the basic model and the component model; According to the subsystem, the subsystem model is created based on the basic model, the component model and the device model.

4. A modeling method for a nuclear energy heating system according to claim 3, characterized in that: The basic equations include: a point reactor neutron kinetic model, a node neutron kinetic model, a reactivity model, a decay heat model, an iodine-xenon kinetic model, three homogeneous flow equations related to the fluid, five two-fluid equations, valve and / or pump characteristic curves, inertial cavity equations, two-zone non-equilibrium state equations, pressure drop, heat transfer coefficient, and pipeline and / or cavity geometry and / or Fourier heat conduction equations related to heat conduction, which are related to the heating system; The basic physical elements include: physical media, interfaces, functions, units, icons and / or boundary conditions.

5. The modeling method of a nuclear energy heating system according to claim 3, characterized in that: The component model includes a pipeline model, a cavity model, a valve model, a pump model, a thermal component model, a fuel rod model and / or a component control model.

6. A modeling method for a nuclear energy heating system according to claim 3, characterized in that: The step of constructing the component model based on the basic model includes: establishing said component models of a plurality of different components; Selecting the base model corresponding to each of the component models; The selected base model is associated with the component model.

7. A modeling method for a nuclear energy heating system according to claim 3, characterized in that: The step of building a device model based on the basic model and the component model comprises: Establishing the device models of a plurality of different devices; Selecting the component model and the base model corresponding to each of the device models; The selected component model and the base model are associated with the corresponding device model.

8. A modeling method for a nuclear energy heating system according to claim 3, characterized in that: The equipment model includes a nuclear island equipment model and / or a conventional island equipment model, wherein the nuclear island equipment model includes: a reactor core, a main heat exchanger, a steam generator and / or a pressurizer; the conventional island equipment model includes a condenser, a shell and tube heat exchanger, a deaerator and / or an air cooler.

9. A modeling method for a nuclear energy heating system according to claim 3, characterized in that: The step of building the subsystem model based on the basic model, the component model and the device model comprises: Establishing a plurality of different subsystem models according to different functions of the heating system; Selecting the component model, the basic model and the device model corresponding to each of the subsystem models; The selected component model, the basic model and the device model are associated with the corresponding subsystem model.

10. A modeling method for a nuclear energy heating system according to claim 3, characterized in that: The subsystem models include: a coolant subsystem, an intermediate loop subsystem, a secondary loop steam subsystem, a feedwater subsystem, a steam generator blowdown subsystem, a waste heat removal subsystem, a safety relief subsystem, a boron injection subsystem, a reactor power control subsystem and / or a nuclear reactor protection subsystem.

11. A modeling system for a nuclear energy heating system, characterized in that: include: A decomposition module, for decomposing the nuclear energy heating system from top to bottom into subsystems, devices, components, basic equations and basic physical elements according to the topological structure of the nuclear energy heating system, the role of each device in the nuclear energy and thermal energy conversion process, and the components and interface structures in each device; A first construction module is used to establish corresponding basic models for the basic equations and basic physical elements, and to establish corresponding component models, device models and subsystem models for the components, devices and subsystems; The second construction module is used to couple the multiple subsystem models based on the Modelica modeling language and according to the topological structure, and combine them with the basic model to construct a simulation model of the nuclear energy heating system.

12. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the modeling method of the nuclear energy heating system according to any one of claims 1 to 10 are implemented.

13. A storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the steps of the modeling method of a nuclear energy heating system as claimed in any one of claims 1 to 10 are implemented.

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