Phase change characteristic experiment system based on main steam release isolating valve

Abstract

The invention relates to a main steam release isolating valve-based phase change characteristic experiment system, which comprises a steam generation device, a pipeline transmission device, a main steam release isolating valve, a valve action monitoring device, a phase change characteristic monitoring device, a parameter monitoring device and a data processing device, the valve action monitoring device is used for detecting the action of a valve rod, the phase change characteristic monitoring device comprises a camera which is aligned with an observation window, the parameter monitoring device is used for detecting the pressure, temperature and other parameters of the main steam release isolating valve, and the data processing device collects and analyzes data. According to the phase change characteristic experiment system based on the main steam release isolating valve, the observation window and the phase change characteristic monitoring device are arranged, real-time dynamic characteristic monitoring of the phase change process of the working medium in the valve cavity can be achieved, the dynamic change characteristic of the main steam release isolating valve can be accurately obtained, and the working efficiency is improved. And a guarantee is provided for long-time safe and stable operation of a nuclear power station steam system.

Description

Technical Field

[0001] The present application relates to the technical field of valve medium flow research, and more specifically, to a phase change characteristic experimental system based on a main steam release isolation valve. Background Art

[0002] Isolation valves are a typical type of valve in the control valves of pipeline systems. They are of great significance to ensure the stable operation of pressure-bearing equipment and the normal operation of pipeline components. When a part of the pipeline system needs to stop working for maintenance and overhaul, or a section of the pipeline has abnormal conditions such as pressure relief and fluid leakage, in order to avoid affecting the normal operation of other components, ensure operational safety, reduce losses, and maintain system integrity, an isolation valve is required to isolate the above-mentioned part of the pipeline from it and provide a stable pressure environment for the normal working equipment.

[0003] In nuclear power plants, the main working fluid of the main steam release isolation valve used in the pressurized water reactor system is steam. When the pipeline system works normally, the main steam release isolation valve can also be used for waste heat discharge. In order to better control the main steam release isolation valve, it is necessary to conduct various test experiments on the dynamic characteristics of the main steam release isolation valve during the opening and closing process. The dynamic characteristics of the main steam release isolation valve have extremely high engineering application value in ensuring the long-term safe and stable operation of the nuclear power plant steam system.

[0004] The experimental device of the prior art focuses on testing and analyzing the conventional action characteristics of the valve opening and closing process, and the working pressure of the valve is single, and the obtained rules do not have good universality. In addition, in the actual working process of the valve, since the working medium is high-temperature steam with a temperature between 200℃ and 300℃ and a pressure between 0.1-6MPa, it is greatly affected by temperature and pressure. Under the conditions of pressure changes in the valve cavity and the heat exchange effect between itself and the external environment, the high-temperature steam will undergo a gas-liquid phase transition to form a condensed liquid. Due to the large difference in density between gas and liquid, the pressure in the valve cavity is reduced, and the pressure difference decreases slowly, affecting the valve core return time. However, the current experimental research lacks analysis and exploration of this phenomenon, and the existing experimental device cannot meet the basic conditions required for this research. Therefore, it is urgent to invent an experimental device for the study of phase change in the main steam release isolation valve. Summary of the invention

[0005] The technical problem to be solved by the present application is to provide a phase change characteristic experimental system based on a main steam release isolation valve, which can observe the phase change phenomenon of the working fluid under the working state of the main steam release isolation valve to study its influence on the dynamic characteristics of the valve.

[0006] The technical solution adopted by the embodiment of the first aspect of the present application to solve the technical problem is: constructing a phase change characteristic experimental system based on the main steam release isolation valve, including:

[0007] A steam generating device for generating high temperature steam;

[0008] A pipeline transmission device connected to the steam generating device, the pipeline transmission device is used to transport high-temperature steam;

[0009] A main steam release isolation valve is connected to the pipeline transmission device, the main steam release isolation valve comprises a valve body, a valve cavity is arranged in the valve body, a steam inlet and a steam outlet communicating with the valve cavity are arranged on the valve body, a valve stem is movably arranged in the valve body, the valve stem controls the connection or blocking of the steam inlet and the steam outlet, and at least one observation window is arranged on the upper part of the valve body;

[0010] A valve action monitoring device, comprising a displacement sensor, wherein the displacement sensor is used to detect the action of the valve stem;

[0011] A phase change characteristic monitoring device, comprising a camera, wherein the camera is aligned with the observation window;

[0012] a parameter monitoring device, comprising a first pressure sensor, a flow meter, a first temperature sensor, a second temperature sensor and a third temperature sensor, wherein the first pressure sensor is used to detect the steam pressure entering the main steam release isolation valve, the flow meter is used to detect the steam flow entering the main steam release isolation valve, the first temperature sensor is used to detect the steam temperature entering the main steam release isolation valve, the second temperature sensor is used to detect the steam temperature coming out of the main steam release isolation valve, and the third temperature sensor is used to detect the steam temperature inside the valve body;

[0013] The data processing device includes an analysis host and a data acquisition device, wherein the analysis host is connected to the data acquisition device, and the data acquisition device is respectively connected to the displacement sensor, the camera, the first pressure sensor, the flow meter, the first temperature sensor, the second temperature sensor and the third temperature sensor, and the data acquisition device collects data and feeds it back to the analysis host.

[0014] In some embodiments of the first aspect of the present application, a pipeline valve is provided on the pipeline transmission device.

[0015] In some embodiments of the first aspect of the present application, a piston-cylinder sleeve is provided on the valve stem, the piston-cylinder sleeve divides the valve chamber into an upper chamber and a lower chamber, the steam inlet and the steam outlet are connected to the lower chamber, and an electromagnetic pilot valve is provided on the valve body, and when the electromagnetic pilot valve is opened, the upper chamber is connected to the outside atmosphere.

[0016] In some embodiments of the first aspect of the present application, a valve cover is disposed on the top of the valve body, a push rod is disposed on the top of the valve stem, and the push rod passes through the valve cover.

[0017] In some embodiments of the first aspect of the present application, the displacement sensor is a laser displacement sensor, the displacement sensor is arranged above the valve body and the displacement sensor faces the valve cover, a receiving gasket facing the displacement sensor is provided on the push rod, and the receiving gasket is located outside the valve body.

[0018] In some embodiments of the first aspect of the present application, a spring is provided between the piston cylinder and the valve cover, and the acting force of the spring causes the valve stem to move downward.

[0019] In some embodiments of the first aspect of the present application, a lens is provided at the observation window, and the lens is connected to the valve body via a high temperature resistant sealing glue.

[0020] In some embodiments of the first aspect of the present application, the first pressure sensor is disposed on the pipeline transmission device, and a first heat sink is disposed between the first pressure sensor and the pipeline transmission device.

[0021] In some embodiments of the first aspect of the present application, an outlet pipe is provided on the main steam release isolation valve, a second pressure sensor is provided on the outlet pipe, and a second heat sink is provided between the second pressure sensor and the outlet pipe.

[0022] In some embodiments of the first aspect of the present application, the phase change characteristic monitoring device includes a horizontal track and a vertical bracket, the vertical bracket is arranged on the horizontal track and the vertical bracket can move horizontally along the horizontal track, and the camera is arranged on the vertical bracket and the camera can move up and down along the vertical bracket.

[0023] The implementation of this application has at least the following beneficial effects: the phase change characteristic experimental system based on the main steam release isolation valve provided by this application can realize real-time dynamic characteristic monitoring of the phase change process of the working fluid in the valve cavity, so as to obtain the dynamic change characteristics of the stress, strain and temperature of the main steam release isolation valve, and provide guarantee for the long-term safe and stable operation of the nuclear power plant steam system. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The present application will be further described below with reference to the accompanying drawings and embodiments, in which:

[0025] Figure 1 The overall structural diagram of the phase change characteristic experimental system based on the main steam release isolation valve provided in this application;

[0026] Figure 2 for Figure 1 Partial assembly drawing of the main steam release isolation valve;

[0027] Figure 3 An isometric view of the main steam release isolation valve provided for this application;

[0028] Figure 4 for Figure 3 Cross-sectional view of the main steam release isolation valve;

[0029] Figure 5 It is a schematic diagram of the structure of the phase change characteristic monitoring device;

[0030] Figure 6 This is the working flow chart of the phase change characteristics experimental system based on the main steam release isolation valve.

[0031] Description of Figure Numbers:

[0032] Steam generating device 100, liquid injection pipeline 110, water level gauge 120, pressure gauge 130, control panel 140, pressure relief safety valve 150, pipeline transmission device 200, thick straight pipeline 210, thin pipeline 220, pipeline valve 230, main steam release isolation valve 300, valve body 310, steam inlet 311, steam outlet 312, upper chamber 313, lower chamber 314, valve stem 320, piston sleeve cylinder 321, push rod 322, valve disc 323, observation window 330, valve body bracket 340, electromagnetic valve Pilot valve 350, valve cover 360, spring 370, air outlet pipe 380, displacement sensor 400, receiving gasket 410, connecting bracket 420, camera 500, vertical bracket 510, horizontal track 520, first pressure sensor 610, first heat sink 611, flow meter 620, first temperature sensor 630, second temperature sensor 640, third temperature sensor 650, second pressure sensor 660, second heat sink 661, data acquisition device 700, analysis host 800. DETAILED DESCRIPTION

[0033] In order to have a clearer understanding of the technical features, purposes and effects of the present application, the specific implementation methods of the present application are now described in detail with reference to the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0034] In the description of the present application, it should be understood that the terms "longitudinal", "lateral", "up", "down", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings or the orientations or positional relationships in which the products of the present application are usually placed when used. They are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0035] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0036] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0037] In the present application, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0038] The following is combined with Figure 1 To Attachment Figure 5 The provided embodiments further illustrate the phase change characteristic experimental system based on the main steam release isolation valve proposed in the present application.

[0039] Reference Figure 1The embodiment of the present application provides a phase change characteristic experimental system based on a main steam release isolation valve, comprising a steam generating device 100, a pipeline transmission device 200, a main steam release isolation valve 300, a valve action monitoring device, a phase change characteristic monitoring device, a parameter monitoring device and a data processing device. The steam generating device 100 is connected to the main steam release isolation valve 300 through the pipeline transmission device 200, the valve action monitoring device, the phase change characteristic monitoring device and the parameter monitoring device are respectively arranged inside or around the main steam release isolation valve 300, and are used to monitor the main steam release isolation valve 300, and the data processing device is respectively electrically connected to the valve action monitoring device, the phase change characteristic monitoring device and the parameter monitoring device, and is used to collect and analyze the monitored data.

[0040] Specifically, in this embodiment, the steam generating device 100 is used to generate high-temperature steam, and the temperature of the high-temperature steam is generally between 200°C and 300°C, and the pressure is between 0.1-6MPa. The steam generating device 100 is provided with a liquid injection pipeline 110, a water level gauge 120, a pressure gauge 130, a control panel 140 and a pressure relief safety valve 150. The working fluid flows into the steam generating device 100 from the liquid injection pipeline 110, and is heated by the heating element inside the steam generating device 100 to generate steam. A pressure gauge 130 is provided above the steam generating device 100 for monitoring the pressure of steam generated inside the steam generating device 100; at the same time, a water level gauge 120 and a pressure relief safety valve 150 are provided above the side of the steam generating device 100. The water level gauge 120 is used to display the internal liquid level in real time and replenish the working fluid in time when the working fluid is insufficient; when the internal pressure of the steam generating device 100 is too high, the pressure relief safety valve 150 opens to release excess steam to the outside to reduce the internal pressure of the steam generating device 100; a control panel 140 is embedded in the front of the steam generating device 100 to realize the functions of flexible pressure regulation and temperature control, and an emergency stop button, a safety alarm light, etc. are provided below the control panel 140. The emergency stop button is used for emergency braking when the phase change characteristic experimental system based on the main steam release isolation valve is out of control, and the safety alarm light is used to indicate whether the working status of the steam generating device 100 is normal.

[0041] The pipeline transmission device 200 includes a thick straight pipeline 210 and a thin pipeline 220. The thick straight pipeline 210 is arranged horizontally, and one end of the thick straight pipeline 210 is connected to the steam outlet end of the steam generating device 100. The pipeline valve 230 is installed on the thick straight pipeline 210 to control the connection and disconnection between the steam generating device 100 and the main steam release isolation valve 300. In this embodiment, the thin pipeline 220 is L-shaped, and the vertical section end of the thin pipeline 220 is connected to the end of the thick straight pipeline 210 away from the steam generating device 100 by welding, and the horizontal section of the thin pipeline 220 is connected to the inlet end of the main steam release isolation valve 300. The pipeline transmission device 200 is used to transport high-temperature steam to the main steam release isolation valve 300. Further, a first pressure sensor 610 and a flow meter 620 are installed in the horizontal section of the thin pipeline 220. The first pressure sensor 610 is used to monitor whether the steam pressure before the main steam release isolation valve 300 reaches the inlet condition, and the flow meter 620 is used to count the amount of steam flowing into the main steam release isolation valve 300.

[0042] like Figure 2 As shown, in this embodiment, the main steam release isolation valve 300 includes a valve body 310, a valve body bracket 340 and an electromagnetic pilot valve 350. The valve body bracket 340 and the valve body 310 are connected by bolts, so that the valve body bracket 340 supports the valve body 310. The electromagnetic pilot valve 350 is installed on the outside of the valve body 310, and the electromagnetic pilot valve 350 is fixed on the outer wall of the valve body 310 by the electromagnetic valve base. At the same time, a solenoid valve connection hole is provided on the valve body 310, and the setting of the solenoid valve connection hole allows steam to flow between the main steam release isolation valve 300 and the electromagnetic pilot valve 350.

[0043] Furthermore, the present application designs two targeted main steam release isolation valves 300 according to the high pressure and low pressure working environments. Figure 3 and Figure 4As shown, in this embodiment, a main steam release isolation valve 300 embodiment for use in a low-pressure environment is provided. Specifically, a valve cover 360 is provided on the top of the valve body 310, a steam inlet 311 and a steam outlet 312 are provided on the valve body 310, the steam inlet 311 is connected to the fine pipe 220, the steam outlet 312 is connected to the gas outlet pipe 380, and a valve cavity is provided in the valve body 310. A valve stem 320 is movably provided in the valve cavity, and a piston sleeve cylinder 321 is provided on the valve stem 320, and the piston sleeve cylinder 321 divides the valve cavity into an upper cavity 313 and a lower cavity 314. The electromagnetic valve connection hole is connected to the upper chamber 313. When the electromagnetic pilot valve 350 is opened, the upper chamber 313 is connected to the outside atmosphere. The steam inlet 311 and the steam outlet 312 are connected to the lower chamber 314. The valve stem 320 controls the connection or blocking of the steam inlet 311 and the steam outlet 312 by moving up and down. Specifically, a valve flap 323 is arranged below the valve stem 320. When the valve stem 320 drops to the lowest position, the valve flap 323 blocks the steam outlet 312 and blocks between the lower chamber 314 and the steam outlet 312. When the valve stem 320 moves upward, the valve flap 323 leaves the steam outlet 312, so that the lower chamber 314 is connected to the steam outlet 312. Further, a spring 370 is arranged between the piston sleeve cylinder 321 and the valve cover 360. The force of the spring 370 causes the valve stem 320 to move downward, which can ensure that the valve flap 323 effectively blocks the steam outlet 312, and when the valve stem 320 moves upward, it promotes the reset of the valve stem 320. The working mechanism of the main steam release isolation valve 300 is as follows: before the valve is opened, the electromagnetic pilot valve 350 working in conjunction with it is closed, the pressure inside the valve is stable, and it has a good sealing effect; the electromagnetic pilot valve 350 is opened first, and the steam in the upper chamber 314 is discharged through the electromagnetic pilot valve 350 connected thereto, and a pressure difference is quickly generated on the upper and lower surfaces of the piston sleeve cylinder 321, thereby generating an upward fluid force, and this fluid force will increase with the increase in the opening of the electromagnetic pilot valve 350; when the fluid force overcomes the elastic force of the spring 370 and the gravity of the valve stem 320 assembly, the valve stem 320 begins to move upward, the valve disc 323 leaves the steam outlet 312, and the valve opens; the electromagnetic pilot valve 350 is closed, the pressure difference between the upper and lower surfaces of the piston sleeve cylinder 321 of the main steam release isolation valve 300 is reduced, and the valve stem 320 is reset under the action of the spring 370.

[0044] Furthermore, a push rod 322 is provided at the top of the valve stem 320, and the top end of the valve stem 320 and the bottom end of the push rod 322 are connected by threads, wherein the bottom end of the push rod 322 is processed with an external thread, and a thread groove is processed in the groove at the top end of the valve stem 320 connected thereto to ensure the strength requirement of the connection, and a threaded fastener is provided at the connection to play a role in sealing and fixing, and the push rod 322 is arranged through the valve cover 360, and the push rod 322 moves with the valve stem 320. Figure 3 , Figure 4As shown, at least one observation window 330 is provided on the upper part of the valve body 310 to facilitate observation of the phase change of the high-temperature steam inside the valve cavity. The observation window 330 can be distributed on the outer side wall and the top of the valve body 310. Figure 3 and Figure 4 The main steam release isolation valve 300 embodiment provided is mainly used in a low-pressure environment, so four observation windows 330 can be provided on the outer side wall of the valve body 310, and an observation window 330 is provided on the top of the valve body 310. A lens is provided at the observation window 330, which can prevent steam leakage and facilitate observation. The lens is made of high-temperature resistant glass, and the lens is connected to the valve body 310 through a high-temperature resistant sealing adhesive.

[0045] In addition, the phase change characteristics experimental system based on the main steam release isolation valve of the present application can also use the main steam release isolation valve 300 under high-pressure environment in a targeted manner. The structure of the main steam release isolation valve 300 under high-pressure environment is roughly the same as the main steam release isolation valve 300 under low-pressure environment described above, but the number of observation windows 330 is smaller, and at the same time, the material requirements for each component and the connection requirements between components are higher, so that it can withstand testing under high-pressure environment.

[0046] like Figure 2 As shown, the valve action monitoring device includes a displacement sensor 400 for detecting the action of the valve stem 320, a receiving gasket 410 and a connecting bracket 420 for fixing the displacement sensor 400. Specifically, the connecting bracket 420 is fixed to the outer wall of the valve body 310 by bolt connection, and the displacement sensor 400 and the connecting bracket 420 are connected by threads, so that the displacement sensor 400 is located directly above the valve body 310, and the displacement sensor 400 faces the direction of the valve cover 360. In this embodiment, the displacement sensor 400 is preferably a laser displacement sensor. The receiving gasket 410 is arranged on the top rod 322 by threaded connection, and the receiving gasket 410 is located above the valve body 310 and directly faces the laser emitting and receiving port of the displacement sensor 400. The receiving gasket 410 moves with the movement of the valve stem 320. The laser emitted by the displacement sensor 400 and then reflected by the receiving gasket 410 can be received by the displacement sensor 400 to represent the movement state and position of the valve stem 320 in real time.

[0047] like Figure 5As shown, in this embodiment, the phase change characteristic monitoring device includes a horizontal track 520, a vertical bracket 510 and a camera 500. The vertical bracket 510 is set on the horizontal track 520 and the vertical bracket 510 can move horizontally along the horizontal track 520. The camera 500 is set on the vertical bracket 510 and the camera 500 can move up and down along the vertical bracket 510. The two degrees of freedom of the camera 500 in space are retained, and the position of the camera 500 is conveniently adjusted so that the camera 500 is aligned with the observation window 330, and edge detection is performed to obtain the phase change of the high-temperature steam in the valve cavity, and the signal is transmitted to the data processing device for further analysis.

[0048] like Figure 1 and Figure 4 As shown, the parameter monitoring device includes a first pressure sensor 610, a flow meter 620, a first temperature sensor 630, a second temperature sensor 640, a third temperature sensor 650 and a second pressure sensor 660. Specifically, the first pressure sensor 610 and the flow meter 620 are installed on the horizontal section of the thin pipe 220, the first pressure sensor 610 is used to monitor the pressure value at the inlet of the main steam release isolation valve 300 in real time, and the flow meter 620 is used to monitor the steam flow flowing into the main steam release isolation valve 300. The first temperature sensor 630 is arranged at the steam inlet 311, and the first temperature sensor 630 is fixed by threading with the flange at the steam inlet 311, and the first temperature sensor 630 monitors the temperature of the steam at the steam inlet 311; the second temperature sensor 640 is arranged at the steam outlet 312, and the second temperature sensor 640 is fixed by threading with the flange at the steam outlet 312, and the second temperature sensor 640 monitors the temperature of the steam at the steam outlet 312; the first temperature sensor 630 and the second temperature sensor 640 are arranged along the direction of steam flow to avoid deformation due to the high pressure of steam. The third temperature sensor 650 is fixed on the valve cover 360 by threading, and is used to test the temperature of the steam in the upper chamber 313 when the phase change occurs. The second pressure sensor 660 is installed on the outlet pipe 380, and the second pressure sensor 660 is used to monitor the pressure of the discharged steam in real time.

[0049] Further, such as Figure 2 As shown, a first heat sink 611 is provided between the first pressure sensor 610 and the thin pipe 220, and a second heat sink 661 is provided between the second pressure sensor 660 and the outlet pipe 380. The first heat sink 611 is connected to the lower end of the first pressure sensor 610 by threads, and the second heat sink 661 is connected to the lower end of the second pressure sensor 660 by threads. The first heat sink 611 and the second heat sink 661 are used to discharge the residual heat of the pipeline to avoid affecting the sensitivity of the first pressure sensor 610 and the second pressure sensor 660.

[0050] The data processing device includes an analysis host 800 and a data acquisition device 700. The analysis host 800 is connected to the data acquisition device 700. The data acquisition device 700 is respectively connected to the displacement sensor 400, the camera 500, the first pressure sensor 610, the flow meter 620, the first temperature sensor 630, the second temperature sensor 640, the third temperature sensor 650 and the second pressure sensor 660. The above sensors transmit the collected signals to the data acquisition device 700, and the data acquisition device 700 integrates and transmits the signals to the analysis host 800 for analysis and processing. Further, a digital twin system is built on the analysis host 800 to map the physical world, and visualize it based on the unity development platform. The dynamic characteristics of the valve structure stress, strain, temperature and displacement are displayed in real time in the virtual world built using C language. At the same time, a software system is developed on the analysis host 800 based on the LabVIEW language to intuitively display the data collected by each sensor and monitor the experimental device in real time.

[0051] like Figure 6 As shown, the present application also provides an experimental method based on a phase change characteristic experimental system of a main steam release isolation valve, comprising the following steps:

[0052] The first step is to start the device so that the steam pressure output by the steam generating device 100 reaches the preset value. Turn on the power, start the valve action monitoring device, the phase change characteristic monitoring device and the parameter monitoring device, debug the various sensors in the pipeline to ensure their normal operation, connect the water source, inject water into the steam generating device 100 through the injection pipe 110, turn on the switch, and set the pressure and temperature of the output steam through the control panel 140; start the data processing device, and the data collected by the various sensors in the pipeline will be displayed on the analysis host 800; when the pressure and temperature reach the set value and tend to be stable, open the pipeline valve 230 to allow the gas to fully fill the entire pipeline.

[0053] The second step is to test the influence of the phase change characteristics of the main steam release isolation valve 300 on the action characteristics. Based on the analysis of the actual working conditions and the strength requirements of the valve structure, when the pressure is at 1-2MPa, it is a low-pressure condition, and the main steam release isolation valve 300 of the low-pressure environment is used (replaced); when the pressure is above 2MPa, it is a high-pressure condition, and the main steam release isolation valve 300 of the high-pressure environment is used (replaced); the high-temperature steam generated by the steam generating device 100 flows into the thick straight pipeline 210 through the pipeline valve 230, flows along the thin pipeline 220, passes through the flow meter 620 and the first pressure sensor 610, and then flows into the main steam release isolation valve 300; Before the main steam release isolation valve 300 is opened, the electromagnetic pilot valve 350 is closed. After the pressure stabilizes, the pressure in the upper chamber 313 and the lower chamber 314 are the same. At this time, the valve stem 320 is pressed on the steam outlet 312; the electromagnetic pilot valve 350 is opened, and the gas in the upper chamber 313 connected thereto is discharged to the atmosphere through the electromagnetic pilot valve 350. Since the airflow cannot be replenished into the upper chamber 313 in time, the pressure in the lower chamber 314 is greater than the pressure in the upper chamber 313, resulting in an upward pressure difference, and the gas in the lower chamber 314 is continuously replenished, so that the pressure difference The valve stem 320 is in a state of being stable, and as the valve opening of the electromagnetic pilot valve 350 increases, the pressure difference generated also gradually increases. When the pressure difference increases to a level sufficient to overcome the gravity of the valve stem 320 assembly, the resistance of the spring 370, and the friction, the valve stem 320 drives the valve disc 323 and the push rod 322 to start moving upward, and the displacement sensor 400 records the displacement of the valve stem 320 in real time until the valve is fully opened. Observe the physical characteristics fed back from the digital twin system and observe the phase change of the steam in the cavity. After the system pressure value stabilizes, close the electromagnetic pilot valve 350 and open the upper cavity. The pressure in chamber 313 gradually increases to be the same as that in lower chamber 314, the pressure difference decreases, the valve stem 320 is reset, and the displacement sensor 400 continuously records the displacement; the data acquisition device 700 transmits the received signal to the analysis host 800, the analysis host 800 receives the pressure, temperature, and displacement signals during the process, performs data processing, and outputs the characteristic curve of the valve opening and closing process. The camera 500 captures the steam condensation in the upper chamber 313, obtains the phase change characteristic curve, and compares and analyzes the influence of steam condensation on the valve action characteristics under low-pressure conditions / high-pressure conditions.

[0054] The third step is data storage and processing.

[0055] Check whether the data obtained after each experimental operation is saved, observe whether there is any abnormal data, whether the phase change characteristic curve obtained from the experiment under high and low working pressures has the same influence on the action characteristic curve, reset the experiment for the working conditions of abnormal data, ensure that the data is accurate, save the data, turn off the device, and end the experiment.

[0056] In the above second step, experiments are conducted on low-pressure conditions and high-pressure conditions respectively, and three groups of working pressures with different values ​​and their corresponding saturated steam temperatures can be set through the control panel 140. For example, for high-pressure conditions, three groups of high working pressures with different values ​​are set through the control panel 140 as follows: (1) 235°C, 3MPa, (2) 251°C, 4MPa, and (3) 265°C, 5MPa. The experiment under each group of working pressures is repeated five times, and the data obtained under the same working pressure are averaged to obtain the action characteristic curve and phase change characteristic curve of the main steam release isolation valve 300, and analyze the influence of steam condensation on the action characteristics of the main steam release isolation valve 300 during the opening and closing process.

[0057] The phase change characteristic experimental system based on the main steam release isolation valve provided in this application can realize real-time dynamic characteristic monitoring of the phase change process of the working fluid in the valve cavity, so as to obtain the dynamic change characteristics of the stress, strain and temperature of the main steam release isolation valve, and provide guarantee for the long-term safe and stable operation of the nuclear power plant steam system.

[0058] The above embodiments only express the specific implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the patent of the present application. It should be pointed out that, for ordinary technicians in this field, without departing from the concept of the present application, the above-mentioned technical features can be freely combined, and several deformations and improvements can be made, which all belong to the protection scope of the present application. Therefore, all equivalent changes and modifications made to the scope of the claims of the present application should belong to the scope covered by the claims of the present application.

Claims

1. A phase change characteristic experimental system based on main steam release isolation valve, characterized in that: include: A steam generating device (100) for generating high-temperature steam; A pipeline transmission device (200) connected to the steam generating device (100), the pipeline transmission device (200) being used to transmit high-temperature steam; A main steam release isolation valve (300) is connected to the pipeline transmission device (200), the main steam release isolation valve (300) comprising a valve body (310), a valve cavity is arranged in the valve body (310), a steam inlet (311) and a steam outlet (312) communicating with the valve cavity are arranged on the valve body (310), a valve stem (320) is movably arranged in the valve body (310), the valve stem (320) controls the connection or blocking of the steam inlet (311) and the steam outlet (312), and at least one observation window (330) is arranged on the upper part of the valve body (310); A valve action monitoring device, comprising a displacement sensor (400), wherein the displacement sensor (400) is used to detect the action of the valve stem (320); A phase change characteristic monitoring device comprises a camera (500), wherein the camera (500) is arranged to be aligned with the observation window (330); A parameter monitoring device, comprising a first pressure sensor (610), a flow meter (620), a first temperature sensor (630), a second temperature sensor (640) and a third temperature sensor (650), wherein the first pressure sensor (610) is used to detect the pressure of steam entering the main steam release isolation valve (300), the flow meter (620) is used to detect the flow of steam entering the main steam release isolation valve (300), the first temperature sensor (630) is used to detect the temperature of steam entering the main steam release isolation valve (300), the second temperature sensor (640) is used to detect the temperature of steam coming out of the main steam release isolation valve (300), and the third temperature sensor (650) is used to detect the temperature of steam inside the valve body (310); The data processing device comprises an analysis host (800) and a data acquisition device (700), wherein the analysis host (800) is connected to the data acquisition device (700), and the data acquisition device (700) is respectively connected to the displacement sensor (400), the camera (500), the first pressure sensor (610), the flow meter (620), the first temperature sensor (630), the second temperature sensor (640) and the third temperature sensor (650), and the data acquisition device (700) collects data and feeds back the data to the analysis host (800).

2. The phase change characteristic experimental system based on the main steam release isolation valve according to claim 1 is characterized in that: The pipeline transmission device (200) is provided with a pipeline valve (230).

3. The phase change characteristic experimental system based on the main steam release isolation valve according to claim 1 is characterized in that: The valve stem (320) is provided with a piston sleeve cylinder (321), and the piston sleeve cylinder (321) divides the valve chamber into an upper chamber (313) and a lower chamber (314). The steam inlet (311) and the steam outlet (312) are connected to the lower chamber (314). The valve body (310) is provided with an electromagnetic pilot valve (350), and when the electromagnetic pilot valve (350) is opened, the upper chamber (313) is connected to the outside atmosphere.

4. The phase change characteristic experimental system based on the main steam release isolation valve according to claim 3 is characterized in that: A valve cover (360) is arranged on the top of the valve body (310), and a push rod (322) is arranged on the top of the valve stem (320), and the push rod (322) passes through the valve cover (360).

5. The phase change characteristic experimental system based on the main steam release isolation valve according to claim 4 is characterized in that: The displacement sensor (400) is a laser displacement sensor, and the displacement sensor (400) is arranged above the valve body (310) and faces the valve cover (360). A receiving gasket (410) facing the displacement sensor (400) is provided on the push rod (322), and the receiving gasket (410) is located outside the valve body (310).

6. The phase change characteristic experimental system based on the main steam release isolation valve according to claim 4 is characterized in that: A spring (370) is provided between the piston cylinder (321) and the valve cover (360), and the force of the spring (370) causes the valve stem (320) to move downward.

7. The phase change characteristic experimental system based on the main steam release isolation valve according to claim 1 is characterized in that: A lens is provided at the observation window (330), and the lens is connected to the valve body (310) via a high-temperature resistant sealing adhesive.

8. The phase change characteristic experimental system based on the main steam release isolation valve according to claim 1 is characterized in that: The first pressure sensor (610) is arranged on the pipeline transmission device (200), and a first heat sink (611) is arranged between the first pressure sensor (610) and the pipeline transmission device (200).

9. The phase change characteristic experimental system based on the main steam release isolation valve according to claim 1 is characterized in that: The main steam release isolation valve (300) is provided with an air outlet pipeline (380), the air outlet pipeline (380) is provided with a second pressure sensor (660), and a second heat sink (661) is provided between the second pressure sensor (660) and the air outlet pipeline (380).

10. The phase change characteristic experimental system based on the main steam release isolation valve according to claim 1 is characterized in that: The phase change characteristic monitoring device comprises a horizontal track (520) and a vertical support (510), wherein the vertical support (510) is arranged on the horizontal track (520) and the vertical support (510) can move horizontally along the horizontal track (520), and the camera (500) is arranged on the vertical support (510) and the camera (500) can move up and down along the vertical support (510).

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