CN114491817B

CN114491817B - Main pipe simulation method and system in ship nuclear power pipe network simulation

Info

Publication number: CN114491817B
Application number: CN202210122499.8A
Authority: CN
Inventors: 孙觊琳; 张博文; 于雷; 成守宇; 彭敏俊; 夏庚磊; 薛若军
Original assignee: Harbin Engineering University
Current assignee: Harbin Engineering University
Priority date: 2022-02-09
Filing date: 2022-02-09
Publication date: 2022-10-04
Anticipated expiration: 2042-02-09
Also published as: CN114491817A

Abstract

The invention discloses a mother pipe simulation method and a system applied to ship nuclear power plant simulation, which are applied to the technical field of mother pipe simulation, specifically, an actual process system is converted into a pipe network model simulation diagram according to the characteristics of a simulation object system, and the boundary between the pipe network system and an external system and the boundary between the pipe network system and a mother pipe model are selected according to the actual structure of the simulation object; drawing according to the simulation graph to which the pipe network boundary belongs, and interacting pressure data and flow data of the pipe network boundary with the mutual interference control body model; determining decoupling and coupling states of the mutual interference control body according to the state of the main pipe isolation valve; and calculating the thermal parameters of the main pipe by using the transmitted boundary data, and feeding back the thermodynamic parameter calculation result to the pipe network model. The invention can simulate the uniform distribution characteristics of pressure and temperature (enthalpy value) in the main pipe under the communication state of the main pipe; under the state that the main pipe is isolated, the characteristics that the pressure and the temperature (enthalpy value) at two sides of the main pipe isolation valve are relatively independent can be simulated.

Description

Main pipe simulation method and system in ship nuclear power pipe network simulation

Technical Field

The invention relates to the technical field of main pipe simulation, in particular to a main pipe simulation method and a main pipe simulation system applied to ship nuclear power pipe network simulation.

Background

Unlike land-based nuclear power plants, marine nuclear power plants often operate on the port and starboard sides asymmetrically or on one isolated side. In the water supply system, condensed water on two side sides is boosted by a water supply pump, collected into a main pipe for distribution, and then sent into steam generators on two sides. Steam systems also have similar headers. The main pipe has larger inner diameter and stronger volume inertia, and the isolation valve is arranged in the middle of the main pipe, so that the unified pressure and temperature characteristics are embodied when the main pipe and the main pipe are in an asymmetric operation state on a port and a starboard. When a traditional pipe network model is adopted for simulation, if a streamline with small resistance is connected between two control bodies for simulation, the control bodies on the two sides are independent calculation individuals, and the communication state cannot be realized in the calculation process to ensure the identity of pressure and temperature; if a control body is adopted for simulation, the identity of thermal parameters can be fed back well, but the isolation process cannot be simulated.

With the progress of ocean power in China, simulation work is deeply involved in the design of a ship power device. At present, the modeling of a thermodynamic system of a ship nuclear power plant still adopts a means consistent with onshore thermal power and nuclear power simulation models. But the land device has huge difference with the ship power device, the working condition change is little, and the state of asymmetric operation can not occur; no matter which of the traditional modeling methods is adopted to model the process system containing the main pipe, all the operation conditions are difficult to simulate, and the design conditions cannot be comprehensively and accurately predicted. In the current modeling method, the control bodies cannot be dynamically split and combined, so that the master pipe simulation is very difficult. Although the main pipe model calculated by the CFD method is accurate and reliable, the calculation time is huge, the quick connection and coupling can not be carried out on the one-dimensional pipe network model of the real-time simulation, and the real-time simulation task can not be completed. In this case, the model is not very reproducible, and not to mention accurate prediction capability, and can only be applied to limited training simulation, and the simulation results in the design and evaluation stages are not reliable and persuasive.

Therefore, an urgent need exists in the art for providing a method and a system for simulating a main pipe, which can simulate comprehensively and accurately and can be applied to ship nuclear power pipe network simulation.

Disclosure of Invention

In view of the above, the invention provides a method and a system for simulating a main pipe applied to ship nuclear power pipe network simulation.

In order to achieve the above purpose, the invention provides the following technical scheme:

a master pipe simulation method applied to ship nuclear power pipe network simulation comprises the following specific steps:

drawing a simulation graph: converting an actual process system into a simulation diagram of a control body, a connecting line and a pipe network model according to the characteristics of a simulation object system, and selecting the boundary between the pipe network system and an external system and the boundary between the pipe network system and a main pipe model according to the actual structure of the simulation object;

parameter transmission: drawing according to the attached simulation diagram, and interacting pressure data and flow data of the pipe network boundary with the mutual interference control body model by using a preset data transmission rule between the pipe network model and the main pipe model;

and (3) calculating: determining decoupling and coupling states of the mutual interference control body according to the state of the main pipe isolation valve; and calculating the thermal parameters of the main pipe by using the transmitted boundary data, and feeding back the thermodynamic parameter calculation result to the pipe network model.

Optionally, in the above method for simulating a main pipe applied to ship nuclear power pipe network simulation, the specific steps of drawing the simulation diagram are as follows:

arranging a control body at a preset position, placing a model icon of the mutual interference control body at the position of the main pipe, and simulating the main pipe;

connecting other control bodies, and connecting the control bodies in series by using connecting wires according to the flow direction sequence;

selecting the external boundary of the pipe network according to the inflow and outflow states of the pipe network and the outside and the mass transfer and heat transfer processes, wherein the boundary is a pressure boundary, a flow boundary, a heat boundary or a temperature boundary;

further, a suitable boundary is reserved for the main pipe in the pipe network model:

a. the pipeline flowing into the main pipe from the pipe network: treating the parent tube as a pressure boundary; the pipe network transmits working medium flow and working medium enthalpy into the main pipe, and receives the main pipe pressure and the main pipe working medium enthalpy fed back by the main pipe;

b. the pipeline flows into the pipe network from the main pipe: taking the main pipe as a flow boundary; the pipe network transmits the pressure and the working medium enthalpy of the working medium into the main pipe, and receives the working medium flow and the working medium enthalpy of the main pipe fed back by the main pipe;

c. the main pipe and other pipelines of the process system only carry out mass transfer and heat transfer, and the heat transfer phenomenon which is carried out without mass transfer does not exist. And thus no temperature and thermal boundaries are set.

Setting a boundary between a pipe network model and an interference control body model according to the flow direction and the flow state between a mother pipe and a pipe network; and connecting the nodes and the boundary of the pipe network and the boundary and the mutual interference control body by using connecting lines to finish drawing the simulation diagram.

Specifically, a mutual interference control body model is set and connected with the boundary in the pipe network model:

a. simulating a main pipe by a pair of mutual interference control bodies, arranging the main pipe at a relevant position in a simulation graph, and arranging an isolation valve in the middle of each mutual interference control body;

b. and the mutual interference control body is used as a boundary to be connected with the boundary of the pipe network model. The method comprises the following steps that a main pipe model feeds back pressure, enthalpy and flow of a pipe network, calculation results of corresponding mutual interference control bodies connected with the pipe network are taken, and the mutual interference control bodies serve as a whole to receive data transmitted by the pipe network model;

c. and connecting the time step variable of the mutual interference control body with the time step variable of the pipe network model.

Optionally, in the above method for simulating a main pipe applied to ship nuclear power pipe network simulation, the parameter transmission step includes the following steps:

pressure boundary of pipe network: parameter transmission between pressure boundaries of a pipe network and a pipe network is carried out according to a pipe network model calculation method; the pipe network boundary transmits the flowing flow and direction and the enthalpy value flowing into the main pipe to the mutual interference control body model of the main pipe, and the mutual interference control body model feeds back the pressure and the outflow enthalpy value of the main pipe;

flow boundary of pipe network: parameter transmission between the flow boundaries of the pipe network and the pipe network is carried out according to a pipe network model calculation method; the pipe network boundary transmits the pressure of the downstream flow and the enthalpy value of the downstream flow into the main pipe to the mutual interference control body model of the main pipe, and the mutual interference control body model feeds back the flow rate and the flow direction of the main pipe and the enthalpy value of the downstream flow out of the main pipe.

Specifically, the pipe network model transmits boundary parameters to the mutual interference control body model:

a. before the first calculation, a pressure boundary and a flow boundary of a pipe network model need to be given with initial boundary values, and the initial boundary values are given by modeling personnel and are not calculation results of a mutual interference control body;

b. in the second and later calculations, the last calculation result of the interference control body is taken for the pressure boundary and the flow boundary of the pipe network model, and the time step is pushed forward;

c. calculating each thermal parameter in the mutual interference control body, namely outputting a first calculation result by adopting a pipe network model, and not setting a boundary initial value;

d. and the time step is transmitted once in each step, and when the time step of the pipe network model is changed, the time step of the calculation model of the mutual interference control body is changed in the same calculation and follows the calculation of the pipe network model.

Optionally, in the above method for simulating a main pipe applied to ship nuclear power pipe network simulation, the calculation steps are as follows:

when the main pipe isolation valve is fully opened or the position of the valve does not influence the flow cross section, the main pipe isolation valve is in a coupling state, the internal pressure and enthalpy values are calculated by using the integral mass conservation mode, and meanwhile, the flow is calculated according to the consistency of an individual and the whole;

when the main pipe isolation valve is in a decoupling state after influencing a flow cross section or is completely closed, the flow is calculated by utilizing a momentum conservation equation depending on the pressure difference between the main pipe isolation valve and the main pipe isolation valve, and the pressure and enthalpy value of each main pipe isolation valve are calculated by utilizing a mass conservation equation of each main pipe isolation valve.

Specifically, the mutual interference control body model judges the coupling state and the decoupling state:

a. the mutual interference control bodies are in a coupling state when the main pipe isolation valve is fully opened, and the mutual interference control bodies are integrated in the coupling state and have the same calculation method as that of a single control body in the pipe network model;

b. the mutual interference control bodies are in a decoupling state when the main pipe isolation valve is fully closed, and the mutual interference control bodies in the decoupling state are two mutually independent bodies and have the same calculation method as the two control bodies in the pipe network model;

c. when the isolation valve is in the non-fully-opened and non-fully-closed states, the state of the mutual interference control body needs to be judged according to the valve characteristics. When the valve does not influence the flow cross section, the mutual interference control body is considered to be in a coupling state; when the valve has an effect on the flow cross-section, the interfering control body is considered to be in a decoupled state;

d. the coupling state and the decoupling state between the mutual interference control bodies can be smoothly and smoothly converted, and the conversion process does not cause the oscillation of the main pipe and the boundary thermotechnical parameters and the divergence of calculation and solution.

Further, the overall pressure and enthalpy of the mutual interference control body in the coupling state are calculated:

a. the mutual interference control body is considered as a whole, the volume parameters of the two control bodies are combined and embodied as a common control body, and the internal whole is calculated by using a lumped parameter method;

b. calculating an enthalpy value in the mutual interference control body based on an integral energy conservation equation of the mutual interference control body and the outside;

c. and calculating the pressure in the mutual interference control body based on the integral mass conservation of the mutual interference control body and the outside.

And (3) carrying out flow calculation between the mutual interference control bodies in a coupling state:

a. listing respective mass conservation equations of the mutual interference control bodies;

b. the flow between the mutual interference control bodies is calculated by the method, and the flow resistance in the main pipe is not considered.

And (3) carrying out flow calculation between the mutual interference control bodies in a decoupling state:

a. in a decoupling state, the mutual interference control bodies are two independent bodies, do not have parameter identity any more, are embodied as two common control bodies, and need to consider the flow resistance in the main pipe;

b. and calculating the flow between the mutual interference control bodies by using the pressure difference between the mutual interference control bodies based on a momentum conservation equation.

And (3) calculating the respective pressure and enthalpy values of the mutual interference control bodies in a decoupling state:

a. the mutual interference control bodies in the decoupling state are two independent control bodies and need to be calculated by respectively applying a lumped parameter method;

b. calculating the pressure of a single control body based on a mass conservation equation of the single control body, and considering the flow between the mutual interference control bodies in the calculation process;

c. and calculating the enthalpy value of the single control body based on an energy conservation equation of the single control body, and considering the flow among the mutual interference control bodies and the energy transfer carried by the flow in the calculation process.

Optionally, in the above method for simulating a main pipe applied to ship nuclear power pipe network simulation, the method further includes: calculating boundary parameters between the pipe networks, finishing the calculation of the step, outputting and carrying out the next calculation:

a. the pipe network is pressure boundary, the pressure of the main pipe and the specific enthalpy of the working medium in the main pipe are directly transmitted to the pipe network, and the flow rate and the flow direction of the boundary are calculated by the pipe network;

b. the pipe network is a flow boundary, the branch flow is calculated by utilizing a momentum conservation equation through the node pressure and the main pipe pressure which are connected with the flow boundary, the flow and the specific enthalpy are transmitted to the pipe network, and the flow and the direction are calculated by the calculation method;

c. after the parameter is transmitted, the calculation of the step is completed, the time step length is accumulated, and the next time step length is calculated;

d. and outputting parameter variables such as the temperature and the pressure of the main pipes, the flow between the main pipes, the calculation time and the like.

A master pipe simulation system applied to ship nuclear power pipe network simulation comprises:

a simulation drawing module: converting an actual process system into a simulation diagram of a control body, a connecting line and a pipe network model according to the characteristics of a simulation object system, and selecting the boundary between the pipe network system and an external system and the boundary between the pipe network system and a main pipe model according to the actual structure of the simulation object;

a parameter transfer module: drawing according to the attached simulation diagram, and interacting pressure data and flow data of the pipe network boundary with the mutual interference control body model by using a preset data transmission rule between the pipe network model and the main pipe model;

a calculation module: determining decoupling and coupling states of the mutual interference control body according to the state of the main pipe isolation valve; and calculating the thermal parameters of the main pipe by using the transmitted boundary data, and feeding back the thermodynamic parameter calculation result to the pipe network model.

Optionally, in the above mother pipe simulation system applied to ship nuclear power pipe network simulation, the simulation graph drawing module includes:

the control body unit is used for setting a control body at a preset position, placing a mutual interference control body model icon at the position of the main pipe and simulating the main pipe; connecting other control bodies, and connecting the control bodies in series by using connecting wires according to the flow direction sequence;

the boundary unit is used for selecting the external boundary of the pipe network according to the inflow and outflow states and the mass transfer and heat transfer processes of the pipe network and the outside, and the boundary type is a pressure boundary, a flow boundary, a heat boundary or a temperature boundary;

further, a suitable boundary is reserved for the master in the pipe network model:

a. the pipeline flowing into the main pipe from the pipe network: regarding the main pipe as a pressure boundary; the pipe network transmits working medium flow and working medium enthalpy into the main pipe, and receives the main pipe pressure and the main pipe working medium enthalpy fed back by the main pipe;

b. the pipeline flowing into the pipe network from the main pipe: the main pipe is taken as a flow boundary; the pipe network transmits the pressure and the enthalpy of the working medium into the main pipe and receives the flow and the enthalpy of the working medium fed back by the main pipe;

c. the main pipe and other pipelines of the process system only carry out mass transfer and heat transfer, and the heat transfer phenomenon which is carried out without mass transfer does not exist. And therefore no temperature and thermal boundaries are set.

The drawing unit is used for setting a boundary between the pipe network model and the mutual interference control body model according to the flow direction and the flow state between the mother pipe and the pipe network; and connecting the nodes and the boundary of the pipe network and the boundary and the mutual interference control body by using connecting lines to finish drawing the simulation diagram.

Specifically, a mutual interference control body model is set and connected with a boundary in a pipe network model:

Optionally, in the above mother pipe simulation system applied to ship nuclear power pipe network simulation, the parameter transmission module includes:

a pressure boundary unit: parameter transmission between pressure boundaries of a pipe network and a pipe network is carried out according to a pipe network model calculation method; the pipe network boundary transmits the flowing flow and direction and the enthalpy value flowing into the main pipe to the mutual interference control body model of the main pipe, and the mutual interference control body model feeds back the pressure and the outflow enthalpy value of the main pipe;

a flow boundary unit: parameter transmission between the flow boundaries of the pipe network and the pipe network is carried out according to a pipe network model calculation method; the pipe network boundary transmits the pressure of the downstream flow and the enthalpy value of the downstream flow into the main pipe to the mutual interference control body model of the main pipe, and the mutual interference control body model feeds back the flow rate and the flow direction of the main pipe and the enthalpy value of the downstream flow out of the main pipe.

b. in the second and later calculations, the last calculation result of the mutual interference control body is taken for the pressure boundary and the flow boundary of the pipe network model, and the time step length is advanced;

c. calculating each thermal parameter in the mutual interference control body, namely outputting a first calculation result by adopting a pipe network model without setting a boundary initial value;

d. the time step is transmitted once in each step, and when the time step of the pipe network model is changed, the time step of the calculation model of the mutual interference control body is changed in the same calculation and follows the calculation of the pipe network model.

Optionally, in the above mother pipe simulation system applied to ship nuclear power pipe network simulation, the calculation module includes:

the judging unit is used for judging whether the state of the main pipe isolation valve or the position of the valve influences the flow section;

the coupling unit is in a coupling state when the main pipe isolation valve is fully opened or the position of the valve does not influence the flow cross section, calculates the internal pressure and enthalpy value by using the mode of integral mass conservation, and calculates the flow according to the consistency of an individual and the whole;

and the decoupling unit is in a decoupling state after the main pipe isolation valve is positioned on the flow cross section or is completely closed, the flow is calculated by utilizing the momentum conservation equation depending on the pressure difference between the main pipe isolation valve and the main pipe isolation valve, and the pressure and enthalpy value of each main pipe isolation valve are calculated by utilizing the mass conservation equation of each main pipe isolation valve.

a. the mutual interference control bodies are in a coupling state when the main pipe isolation valve is fully opened, and the mutual interference control bodies in the coupling state form a whole and have the same calculation method as that of a single control body in the pipe network model;

c. when the isolation valve is in the non-fully-open and non-fully-closed states, the state of the mutual interference control body needs to be judged according to the valve characteristics. When the valve does not affect the flow cross section, the mutual interference control body is considered to be in a coupling state; when the valve has an influence on the flow cross section, the mutual interference control body is considered to be in a decoupling state;

Calculating the respective pressure and enthalpy values of the mutual interference control bodies in a decoupling state:

a. the mutual interference control bodies in the decoupling state are two independent control bodies and need to be calculated by using a lumped parameter method respectively;

Optionally, in the above mother pipe simulation system applied to ship nuclear power pipe network simulation, the system further includes: calculating boundary parameters between the pipe networks, finishing the calculation of the step, outputting and carrying out the next calculation:

c. after the parameter is transmitted, the calculation of the step is completed, the time step is accumulated, and the next time step is calculated;

According to the technical scheme, compared with the prior art, the invention discloses a main pipe simulation method and system which are oriented to ship nuclear power pipe network simulation application and have two states of isolation and communication, wherein a pair of mutual interference control bodies are used for simulating a main pipe, and the main pipe is connected with a pipe network model through a boundary; simulating the communication and isolation state of the port and starboard sides of the main pipe by adjusting the coupling and decoupling states between the mutual interference control bodies; simulating a main pipe in a communication state by using a large control body in a coupling state, wherein parameters have identity and uniform distribution; the two sub-control bodies in the decoupling state are used for simulating the main pipe in the isolation state, and the parameters have independence. Finally, the pressure, enthalpy and flow in the mother pipe under different states are calculated through the mass and energy conservation and the flow calculation among the mutual interference control bodies.

Compared with the current master pipe simulation method adopting a pipe network model, the method for simulating the state and the parameters of the ship nuclear power device meets the calculation precision requirement of the master pipe in the asymmetric operation state, predicts or reproduces the operation characteristics of the master pipe equipment, and meets the requirement of the ship nuclear power device on the refined simulation of the master pipe equipment in the model construction processes of design, check, evaluation, training and the like. And the model can be coupled and decoupled, and the isolation and communication working conditions of the main pipe can be smoothly and smoothly realized.

The invention can adopt a simulation method different from the prior pipe network simulation mode when simulating the main pipe equipment in the process system of the ship nuclear power plant, and has the main advantages that:

(1) The mutual interference control body simulation method provided by the invention has two states of coupling and decoupling, is integrated in the coupling state, has consistent calculation results of thermal parameters and uniform distribution, and conforms to an actual main pipe; the two independent bodies are in a decoupling state, independent thermal parameter attributes are provided, and the calculation results can reflect the relative independence of the port side and the starboard side in an isolation state.

(2) The mutual interference control body provided by the invention is relatively independent in calculation and is coupled with the pipe network model through a boundary, so that the models have good coupling, the calculation process is relatively independent, the connection and disconnection of the interface can be rapidly realized in the model reconstruction process, and the rapid reconstruction process of the models is realized.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.

FIG. 1 is a block diagram of a process flow of a master pipe simulation method of the present invention.

FIG. 2 is a process flow diagram of an actual water system.

FIG. 3 is a simulation diagram of a water supply system using a simulation of an interfering controller and a pipe network.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without making any creative effort based on the embodiments in the present invention, belong to the protection scope of the present invention.

The mutual interference control body simulation method disclosed by the embodiment of the invention has two states of coupling and decoupling, is integrated in the coupling state, has consistent calculation results of thermal parameters and uniform distribution, and conforms to an actual main pipe; the two independent individuals are in a decoupling state, the two independent individuals have independent thermal parameter attributes, and the calculation result can reflect the relative independence of the port side and the starboard side in an isolation state. Meanwhile, the mutual interference control body is relatively independent in calculation and is coupled with the pipe network model through a boundary, so that the models have good coupling, the calculation process is relatively independent, the connection and disconnection of the interfaces can be rapidly realized in the model reconstruction process, and the rapid reconstruction process of the models is realized.

The embodiment of the invention discloses a main pipe simulation method applied to ship nuclear power pipe network simulation, which comprises the following specific steps as shown in figure 1:

parameter transmission: drawing according to the simulation diagram, and interacting pressure data and flow data of the pipe network boundary with the mutual interference control body model by using a preset data transmission rule between the pipe network model and the main pipe model;

In order to further optimize the above technical solution, the specific steps of drawing the simulation diagram are as follows:

selecting the external boundary of the pipe network according to the inflow and outflow states of the pipe network and the outside and the mass transfer and heat transfer processes, wherein the boundary type is a pressure boundary, a flow boundary, a heat boundary or a temperature boundary;

In order to further optimize the above technical solution, the parameter transferring step includes the following steps:

flow boundary of pipe network: parameter transmission between the flow boundaries of the pipe network and the pipe network is carried out according to a pipe network model calculation method; the pipe network boundary transmits the pressure of the downstream flow and the enthalpy value of the flow flowing into the main pipe to the mutual interference control body model of the main pipe, and the mutual interference control body model feeds back the flow rate and the flow direction of the main pipe and the enthalpy value of the flow flowing out of the main pipe.

In order to further optimize the technical scheme, the calculation steps are as follows:

when the main pipe isolation valve is fully opened or the position of the valve does not influence the flow cross section, the mutual interference control body is in a coupling state, the pressure and enthalpy values in the mutual interference control body are calculated by using the overall mass conservation mode, and meanwhile, the flow is calculated according to the consistency of the individual mutual interference control body and the whole body;

when the main pipe isolation valve is positioned after the flow cross section is influenced or is completely closed, the mutual interference control bodies are in a decoupling state, the flow is calculated by utilizing a momentum conservation equation and depending on the pressure difference between the mutual interference control bodies, and the pressure and enthalpy values of each mutual interference control body are calculated by utilizing the mass conservation equation of each mutual interference control body.

Specifically, the method comprises the following steps:

a. and judging the state of the mutual interference control body. When the main pipe isolation valve is fully opened or the position of the valve does not influence the flow cross section, the mutual interference control body is in a coupling state and is a whole; when the main pipe isolation valve is positioned after the flow cross section is influenced or is completely closed, the mutual interference control bodies are in a decoupling state and are two independent bodies;

b. when the mutual interference control body is in a coupling state, the pressure in the control body is calculated in a mode of integral mass conservation. Wherein the overall conservation of mass equation is as follows:

where M refers to mass, τ refers to time, ρ refers to density, V refers to volume, f refers to mass flow, lower corner 1 refers to interfering control 1, corner 2 refers to interfering control 2, in refers to inflow, and out refers to outflow.

Considering that density is a function of pressure and enthalpy, the above equation is put into a mode of pressure solution:

where P denotes the pressure and h denotes the specific enthalpy. The coupled state of the main pipe pressure can be solved by using the equation.

c. When the mutual interference control body is in a coupling state, the enthalpy value in the control body is calculated in a mode of overall energy conservation. Wherein the overall energy conservation equation is as follows:

where H refers to the total enthalpy in the control body. Combining an energy equation and a mass equation, and converting into a solution mode of specific enthalpy:

the specific enthalpy of the main pipe working medium in the coupling state can be solved by using the equation.

d. When the mutual interference control body is in a coupling state, the pressure between the individual mutual interference control body and the whole body is consistent, the change speed of the pressure is consistent, and the following relations exist:

and (c) establishing a calculation equation of the pressure according to the step (b) by the mutual interference control body 1 as follows:

wherein f is _2→1 Indicating the flow rate delivered by the interfering control entity 2 to the interfering control entity 1. The pressure equation of the combined mutual interference control body 1 and the whole body is as follows:

the flow between the mutual interference control bodies in the coupling state can be calculated through the equation.

e. When the mutual interference control bodies are in a decoupling state, the flow is calculated by utilizing a momentum conservation equation and depending on the pressure difference between the mutual interference control bodies:

where ζ is the resistance coefficient introduced by the valve. The flow coefficient KV of the valve is introduced into the equation, and the relation between the flow between the mutual interference control bodies and the valve KV can be obtained:

the flow between the mutual interference control bodies in the decoupling state can be calculated through the equation.

f. And when the mutual interference control bodies are in a decoupling state, calculating the pressure of each mutual interference control body by using the self mass conservation equation of each mutual interference control body. The pressure calculation method of the mutual interference control body 1 is the same as the method in the step d, and the calculation method of the mutual interference control body 2 is as follows:

g. when the mutual interference control bodies are in a decoupling state, the specific enthalpy of each mutual interference control body is calculated by using the self energy conservation equation of each mutual interference control body. The solving method of the two mutual interference control bodies comprises the following steps:

specifically, after the pressure and specific enthalpy of the mutual interference control body are calculated, if the pipe network is a pressure boundary, the pressure of the main pipe is directly transmitted back to the pipe network, and the flow rate is calculated by the pipe network; and e, if the pipe network is a flow boundary, calculating the flow by the method in the step e, and transmitting the flow back to the pipe network after the calculation is finished. And when the data is transmitted, advancing the time step length forward and outputting the parameters, and finishing the calculation.

The invention discloses a main pipe simulation system applied to ship nuclear power pipe network simulation, which comprises the following steps:

a simulation drawing module: converting an actual process system into a simulation graph of an interference control body, a connecting line and a main pipe model according to the characteristics of a simulation object system, and selecting the boundary between a pipe network system and an external system and the boundary between the pipe network system and the main pipe model according to the actual structure of the simulation object;

In order to further optimize the above technical solution, the module for drawing a simulation graph includes:

the control body unit is provided with a control body at a preset position, and a mutual interference control body model icon is placed at the position of the main pipe to simulate the main pipe; connecting other control bodies, and connecting the control bodies in series by using connecting wires according to the flow direction sequence;

the boundary unit is used for selecting the external boundary of the pipe network according to the inflow and outflow states of the pipe network and the outside and the mass transfer and heat transfer processes, and the boundary type is a pressure boundary, a flow boundary, a heat boundary or a temperature boundary;

the drawing unit is used for setting the boundary between the pipe network model and the mutual interference control body model according to the flow direction and the flow state between the mother pipe and the pipe network; and connecting the nodes and the boundary of the pipe network and the boundary and the mutual interference control body by using connecting lines to finish drawing the simulation diagram.

In order to further optimize the above technical solution, the parameter passing module includes:

In order to further optimize the above technical solution, the calculation module includes:

and the decoupling unit is in a decoupling state after the main pipe isolation valve is positioned on the flow cross section or is completely closed, the flow is calculated by utilizing the momentum conservation equation depending on the pressure difference, and the pressure and enthalpy value of each is calculated by utilizing the mass conservation equation of each self.

Specifically, according to the judgment result of the judgment unit:

a. and judging the state of the mutual interference control body. When the main pipe isolation valve is fully opened or the position of the valve does not influence the flow cross section, the mutual interference control body is in a coupling state and is a whole; when the main pipe isolation valve is in a state of influencing a flow section or is completely closed, the mutual interference control body is in a decoupling state and is two independent bodies;

c. When the mutual interference control body is in a coupling state, the enthalpy value in the control body is calculated in a whole energy conservation mode. Wherein the overall energy conservation equation is as follows:

d. When the mutual interference control body is in a coupling state, the pressure between the individual mutual interference control body and the whole body is consistent, the change speed of the pressure is consistent, and the following relations are provided:

and (c) establishing a calculation equation of the pressure according to the step b through the mutual interference control body 1 as follows:

wherein f is _2→1 Indicating the flow rate delivered by the interfering controller 2 to the interfering controller 1. The pressure equation of the combined mutual interference control body 1 and the whole body is as follows:

f. When the mutual interference control bodies are in a decoupling state, the pressure of each mutual interference control body is calculated by using the self mass conservation equation of each mutual interference control body. The pressure calculation method of the mutual interference control body 1 is the same as the method in the step d, and the calculation method of the mutual interference control body 2 is as follows:

further, after the pressure and the specific enthalpy of the mutual interference control body are calculated, if the pipe network is a pressure boundary, the pressure of the main pipe is directly transmitted back to the pipe network, and the flow rate is calculated by the pipe network; and e, if the pipe network is a flow boundary, calculating the flow by the method in the step e, and transmitting the flow back to the pipe network after the calculation is finished. And when the data is transmitted, advancing the time step length forward and outputting the parameters, and finishing the calculation.

The application of the simulation method provided by the present invention in an actual process system is described with reference to fig. 2-3. Wherein, fig. 2 is a flow chart of a certain actual water supply system, and fig. 3 is a simulation chart of a pipe network model with a main pipe drawn by the method of the invention.

(1) The method for drawing the simulation graph specifically comprises the following steps:

a. according to the position distribution of the equipment such as valves, pumps and the like in the figure 2, 6 control bodies are arranged at proper positions, and 1 simulation main pipe with mutual interference control body model icons is arranged at the position of the main pipe;

b. connecting other control bodies 1-6 except the mutual interference control body representing the main pipe, and connecting the nodes in series by using connecting wires in sequence according to the flow direction;

c. according to the inflow and outflow states and the mass and heat transfer processes of a pipe network and the outside,

pressure boundaries

91 and 92 are selected for a condensed water inlet,

pressure boundaries

93 and 94 are selected for a water supply outlet, and pressure boundaries 95 and 96 are selected for a condensed water return port;

d. and setting the boundary between the pipe network model and the mutual interference control body model according to the flow direction and the flow state between the mother pipe and the pipe network. Wherein, the condensed water of the working medium flowing into the main pipe from the pipe network is provided with

pressure boundaries

97 and 98; when working media flow into the water supply set

flow boundaries

123 and 124 of the pipe network from the main pipe, the condensed water flows back to set

flow boundaries

121 and 122; and connecting the nodes and the boundary of the pipe network and the boundary and the mutual interference control body by using connecting lines to finish the drawing work of the simulation diagram, as shown in fig. 3.

(2) The specific application method of the parameter transmission link is as follows:

a. pressure boundary 97: the pipe network transmits No. 5 linear flow and working medium specific enthalpy to the main pipe, and the main pipe transmits the pressure of the mutual interference control body 1 and the internal working medium specific enthalpy to a pipe network boundary 97;

b. pressure boundary 98: the pipe network transmits the No. 6 linear flow and the working medium specific enthalpy to the main pipe, and the main pipe transmits the pressure of the mutual interference control body 2 and the internal working medium specific enthalpy to the pipe network boundary 98;

c. flow boundary 123: the pipe network transmits the pressure and specific enthalpy of the No. 5 node to the main pipe, and the main pipe transmits the output flow to the No. 7 wire and the specific enthalpy of the working medium of the mutual interference control body 1 to the pipe network boundary 123;

d. flow boundary 124: the pipe network transmits the pressure and specific enthalpy of the No. 6 node to the main pipe, and the main pipe transmits the output flow to the No. 9 wire and the specific enthalpy of the working medium of the mutual interference control body 2 to the pipe network boundary 124;

e. flow boundary 121: the pipe network transmits the pressure and specific enthalpy of the boundary 95 to the main pipe, and the main pipe transmits the output flow to a No. 11 wire and the working medium specific enthalpy of the mutual interference control body 1 to the pipe network boundary 121;

f. flow boundary 122: the pipe network transmits the pressure and specific enthalpy of the boundary 96 to the main pipe, and the main pipe transmits the output flow to the No. 12 wire and the specific enthalpy of the working medium of the mutual interference control body 2 to the pipe network boundary 122.

(3) The specific application method of the calculation link is as follows:

a. and judging the state of the mutual interference control body. In FIG. 3, the interfering control bodies 1 and 2 are considered to be coupled and integral when the bus isolation valve position does not affect the flow cross-section; when the main pipe isolation valve influences the flow section or is completely closed, the mutual interference control bodies 1 and 2 are in a decoupling state and are two independent bodies;

b. when the mutual interference control bodies are in a coupling state, the pressure in the control bodies and the enthalpy value in the control bodies are calculated in a whole mass conservation mode, the enthalpy value flows into No. 5 and No. 6 lines, and the enthalpy value flows out of No. 7, no. 9, no. 11 and No. 12 lines;

c. when the mutual interference control body is in a coupling state, the pressure between the individual mutual interference control body and the whole body is consistent, the change speed of the pressure is consistent, and the flow passing through the main pipe isolation valve is determined according to the pressure:

d. when the mutual interference control bodies are in a decoupling state, calculating the flow by using a momentum conservation equation and depending on the pressure difference between the mutual interference control bodies;

e. when the mutual interference control bodies are in a decoupling state, the pressure of each mutual interference control body is calculated by using the mass conservation equation of each mutual interference control body, and the specific enthalpy of each mutual interference control body is calculated by using the energy conservation equation of each mutual interference control body. For the mutual interference control body 1, the inflow is No. 5 wire, the flow of the mutual interference control body 2 to the mutual interference control body 1 is No. 7 and No. 11 wire; for the mutual interference control body 2, the inflow is No. 6 wire, and the outflow is the flow of the mutual interference control body 2 to the mutual interference control body 1 and No. 9 and No. 12 wires;

f. and calculating and transmitting boundary parameters. Directly transmitting the pressure of the mutual interference control body 1 to a pressure boundary 97, transmitting the pressure of the mutual interference control body 2 to a pressure boundary 98, and calculating the

flow

5 and 6 by a pipe network; and calculating the flow of the

lines

7, 9, 11 and 12 through a momentum equation, and transmitting the flow back to the pipe network after the calculation is finished. And when the data is transmitted, advancing the time step forward and outputting the parameters, and finishing the calculation at the step.

The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. The device disclosed by the embodiment corresponds to the method disclosed by the embodiment, so that the description is simple, and the relevant points can be referred to the method part for description.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A master pipe simulation method applied to ship nuclear power pipe network simulation is characterized by comprising the following specific steps:

and (3) calculating: determining decoupling and coupling states of the mutual interference control body according to the state of the main pipe isolation valve; calculating the thermal parameters of the main pipe by using the transmitted boundary data, and feeding back the thermodynamic parameter calculation result to the pipe network model; specifically, the overall pressure and enthalpy of the mutual interference control body in the coupling state are calculated as follows:

a. the mutual interference control body is considered as a whole, the volume parameters of the two control bodies are combined to be reflected as a common control body, and the whole interior is calculated by using a lumped parameter method;

b. calculating an enthalpy value in the mutual interference control body based on an overall energy conservation equation of the mutual interference control body and the outside;

c. calculating the pressure in the mutual interference control body based on the integral mass conservation of the mutual interference control body and the outside;

b. the pressure and the pressure change rate which are consistent between each individual and the whole of the mutual interference control bodies are kept, the flow between the mutual interference control bodies is calculated by using the method, and the flow resistance in the main pipe is not considered;

b. calculating the flow between the mutual interference control bodies based on a momentum conservation equation by using the pressure difference between the mutual interference control bodies;

c. and calculating the enthalpy value of the single control body based on the energy conservation equation of the single control body, wherein the flow between the mutually interfered control bodies and the energy transfer carried by the flow are considered in the calculation process.

2. The method for simulating the main pipe applied to the simulation of the ship nuclear power pipe network according to claim 1, wherein the specific steps for drawing the simulation diagram are as follows:

3. The main pipe simulation method applied to ship nuclear power pipe network simulation, according to claim 1, is characterized in that the parameter transmission step comprises the following steps:

4. The method for simulating the main pipe applied to the simulation of the ship nuclear power pipe network according to claim 1, wherein the calculation steps are as follows:

when the main pipe isolation valve is fully opened or the position of the valve does not influence the flow cross section, the mutual interference control body is in a coupling state, the pressure and enthalpy values in the mutual interference control body are calculated by using the overall mass conservation mode, and meanwhile, the flow is calculated according to the consistency of the individual and the overall mutual interference control body;

5. The utility model provides a be applied to female pipe analog system in boats and ships nuclear power pipe network simulation which characterized in that includes:

a simulation graph drawing module: converting an actual process system into a simulation diagram of a control body, a connecting line and a pipe network model according to the characteristics of a simulation object system, and selecting the boundary between the pipe network system and an external system and the boundary between the pipe network system and a main pipe model according to the actual structure of the simulation object;

a calculation module: determining decoupling and coupling states of the mutual interference control body according to the state of the main pipe isolation valve; calculating the thermal parameters of the main pipe by using the transmitted boundary data, and feeding back the thermodynamic parameter calculation result to the pipe network model; specifically, the overall pressure and enthalpy of the mutual interference control body in the coupling state are calculated as follows:

b. calculating the flow between the mutual interference control bodies by utilizing the pressure difference between the mutual interference control bodies based on a momentum conservation equation;

6. The system for simulating the main pipe applied to the simulation of the nuclear power pipe network of the ship according to claim 5, wherein the module for drawing the simulation graph comprises:

7. The main pipe simulation system applied to ship nuclear power pipe network simulation of claim 5, wherein the parameter transmission module comprises:

a flow boundary unit: parameter transmission between the flow boundaries of the pipe network and the pipe network is carried out according to a pipe network model calculation method; the pipe network boundary transmits the pressure of the downstream flow and the enthalpy value of the flow flowing into the main pipe to the mutual interference control body model of the main pipe, and the mutual interference control body model feeds back the flow rate and the flow direction of the main pipe and the enthalpy value of the flow flowing out of the main pipe.

8. The system of claim 5, wherein the calculation module comprises:

the judging unit is used for judging whether the state of the main pipe isolation valve or the position of the valve affects the flow section;