Containment nozzle based on active and passive scenes and working method thereof

Abstract

The invention relates to the technical field of nuclear industry safety, in particular to a containment nozzle based on active and passive scenes and a working method of the containment nozzle. The nozzle comprises a shell, a valve element, a valve plate and a damping mechanism. The shell is provided with a cavity, and the cavity is provided with a fluid inlet and a fluid outlet; the valve element is located in a cavity in one end of a fluid outlet of the shell and divides the cavity into a first flow channel and a second flow channel. The valve plate is positioned in a cavity at one end of a fluid inlet of the shell; the head end of the valve plate is rotationally connected with the shell; one end of the damping mechanism is installed on the wall of the cavity of the shell, the other end of the damping mechanism is connected to the valve plate, and the tail end of the valve plate can be connected to the valve plate in a lap joint mode. The problems that in the prior art, a nozzle cannot adapt to active and passive scenes at the same time, system redundancy is caused, and the cost is increased are solved, the in-reactor operation safety and reliability are improved, and the economical efficiency requirement is met.

Description

Technical Field

[0001] The present invention relates to the technical field of nuclear industry safety, and particularly to a containment nozzle and its working method under active and passive scenarios. Background Art

[0002] As a clean energy source, nuclear energy occupies an important position in the energy structure. As a safe, low-carbon, and stable power source, nuclear power is becoming increasingly important. The containment spray system is one of the key safety systems of a nuclear power plant. Its function is to reduce the temperature and pressure inside the containment in case of emergencies such as the rupture of a high-temperature and high-pressure steam flow path in the reactor cavity, so as to ensure the safety of the reactor.

[0003] A passive system refers to a system composed entirely of passive components, or a system that uses very limited active components to initiate subsequent passive processes. Passive components do not rely on external inputs (force, power, signal, manual operation). Their effects depend on natural physical laws (such as gravity, natural convection, heat conduction, etc.), inherent characteristics (such as material properties, etc.) or energy within the system (such as chemical reactions, decay heat, etc.). That is, the concept of passive technology refers to the characteristics of passive devices (passive devices) based on the principle of inertia (such as the coasting of a pump), the law of gravity (such as head difference), the law of heat transfer, etc., that is, the realization of their functions does not rely on external power. The application of passive safety systems makes the system in a fail-safe state, improves the system safety, and reduces the core melting probability by 1 to 2 orders of magnitude. It should be said that passive technology in nuclear power more refers to passive safety technology. At the same time, passive systems improve the economy of the system by reducing active devices, eliminating or reducing the requirements for emergency power supplies, and reducing the in-service inspection and maintenance of equipment.

[0004] The containment spray system is an important safety system of a nuclear power plant. When a high-temperature and high-pressure steam flow path rupture in the reactor cavity causes mass and energy release, it will lead to an increase in the temperature and pressure inside the containment. In this case, the operation of the spray system inside the containment will be triggered. The spray water is transported from the water supply equipment to a high position inside the containment by an external force drive method (such as a water pump), and then transported to the nozzle through a diverter and a diverter pipe and sprayed into the cavity, playing a role in cooling and pressure reduction. And the nozzle, as the terminal device in the spray system, affects the normal operation of the entire system. Under the existing technical conditions, when the containment spray system is operating, the medium flow rate in the diverter pipe increases rapidly. At this time, the pressure in the diverter pipe is at a relatively high level, and the nozzle valve plate opens, allowing the medium in the pipe to be released to the outside.

[0005] Therefore, the nozzles of the existing spray systems have the following problems: In the active scenario, a large flow rate of spraying is required, while in the passive scenario, due to insufficient pressure, it is difficult for the same nozzle to meet the flow rate and flow velocity requirements of both scenarios. If the solution of using two sets of independent nozzles is adopted, it will lead to the complication of the flow channel layout, increasing the equipment manufacturing cost and the maintenance difficulty. Summary of the Invention

[0006] Aiming at the deficiencies of the existing technology, the purpose of the embodiments of the present invention is to provide a containment spray system nozzle for nuclear power plants that is simple in structure and reliable in operation, based on active and passive scenarios, to solve the problems in the existing technology that the nozzle cannot adapt to both active and passive scenarios simultaneously, as well as the problems of system redundancy and increased cost, and to improve the safety and reliability of in-core operation and meet the economic requirements.

[0007] To achieve the above purpose, the embodiments of the present invention provide the following technical solutions:

[0008] A containment nozzle based on active and passive scenarios includes: a housing, a valve core, a valve plate, and a damping mechanism; the housing has a cavity, and the cavity has a fluid inlet and a fluid outlet; the valve core is located in the cavity at one end of the fluid outlet of the housing and divides the cavity into a first flow channel and a second flow channel; the valve plate is located in the cavity at one end of the fluid inlet of the housing, and the head end of the valve plate is rotatably connected to the housing; one end of the damping mechanism is installed on the cavity wall of the housing, and the other end is connected to the valve plate and can attach the end of the valve plate to the valve plate.

[0009] Optionally, the housing includes a valve body and a nozzle head, the cavity includes a straight cavity section and an inclined cavity section, the inclined cavity section is located at one end of the fluid inlet of the housing, and the straight cavity section is located at one end of the fluid outlet of the housing.

[0010] Optionally, the valve core is arranged in the straight cavity section of the cavity, and the valve plate is arranged in the inclined cavity section of the cavity.

[0011] Optionally, the head end of the valve plate is the end close to the fluid inlet, and the head end of the valve plate is rotatably installed at the fluid inlet of the housing through a rotating shaft.

[0012] Optionally, when the valve plate is attached to the valve core, the second flow channel is closed, and the fluid inlet is only communicated with the first flow channel.

[0013] Optionally, the rotating shaft and the damping mechanism are installed on the same side wall of the cavity.

[0014] Optionally, the damping mechanism is a spring, one end of the spring is connected to the cavity wall corresponding to the second flow channel, and the other end abuts against the valve plate. Under the initial conditions, the spring is in a compressed state.

[0015] Optionally, the damping mechanism is an elastic sheet. One end of the elastic sheet is mounted on the cavity wall, and the other end of the elastic sheet is attached to the back of the valve sheet, pushing the valve sheet towards the valve core.

[0016] Optionally, the rotating shaft and the damping mechanism are installed on different side walls of the cavity. The damping mechanism is a spring. One end of the spring is connected to the cavity wall corresponding to the first flow channel, and the other end abuts against the valve sheet. Under the initial condition, the spring is in a stretched state.

[0017] The embodiment of the present invention also provides a working method of the containment nozzle based on active and passive scenarios as described above, including:

[0018] In the passive scenario, the impact force of the medium cannot overcome the resistance of the damping mechanism to open the valve sheet. The tail end of the valve sheet abuts against the valve core, and the medium flows out from the fluid outlet through the first flow channel from the fluid inlet.

[0019] In the active scenario, the impact force of the medium can overcome the resistance of the damping mechanism to open the valve sheet, enabling the fluid inlet to communicate with the second flow channel. The medium flows out from the fluid outlet through the first flow channel and the second flow channel from the fluid inlet, and the opening degree of the valve sheet can be adjusted in real time according to the medium flow rate.

[0020] One or more technical solutions provided in the embodiment of the present invention have at least the following technical effects or advantages:

[0021] 1. The nozzle includes a housing, a valve core, a valve sheet, and a damping mechanism. The cavity of the housing and the settings of the fluid inlet and outlet provide a channel for the medium flow. The valve core divides the cavity into a first flow channel and a second flow channel, realizing the diversion of the medium flow direction. The valve sheet is located at one end of the fluid inlet, and its head end is rotatably connected to the housing, and can rotate according to the impact force of the medium, thereby controlling the opening and closing of the flow channel, which can not only meet the active scenario (the scenario of high flow rate and large flow volume driven by external force), but also adapt to the passive scenario (the scenario of driving water source by the gravitational potential energy of the top water tank, with a small flow volume). One end of the damping mechanism is installed on the cavity wall of the housing, and the other end is connected to the valve sheet. The opening degree of the valve sheet is adjusted through the damping effect, so that the valve sheet maintains a suitable position under different medium flow rates, improving the safety and reliability of in-pile operation, and achieving cost savings and meeting economic requirements.

[0022] 2. The spool in the nozzle is fixedly installed at the axial position of the straight cavity section. The flow channel is divided into two independent channels by an extended partition plate, ensuring that the medium can flow along a predetermined path when flowing through the straight cavity section. The valve plate is arranged in the inclined cavity section at one end of the fluid inlet. The rotation plane forms an angle with the medium flow direction, and it can be impacted by the impact force immediately when the medium enters the nozzle, thereby controlling the opening and closing of the flow channel, ensuring that the medium can accurately flow into the corresponding flow channel according to the requirements, guaranteeing the fluid continuity during the flow channel switching process, and achieving precise control of the medium flow direction by the nozzle.

[0023] 3. The working process of this nozzle includes two modes: In the passive mode, the kinetic energy of the medium driven by gravity can only maintain the flow in the first flow channel, and the resistance moment provided by the damping mechanism is greater than the fluid impact moment, keeping the flow channel as a single passage; in the active mode, the high-pressure fluid generated by the external force drive forms sufficient impact moment, and the two flow channels are opened proportionally through the dynamic balance mechanism. The greater the flow rate, the higher the opening degree of the second flow channel, forming an adaptive flow distribution.

[0024] Advantages of additional aspects of the present invention will be given in the following description, some of which will become obvious from the following description, or can be learned through the practice of the present invention. Description of the Drawings

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments recorded in the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings. In addition, the distances or sizes between each part are exaggerated for showing the positions, and the schematic diagrams are only for illustration.

[0026] Figure 1 It is a schematic diagram of the closed state of the second flow channel provided by the embodiment of the present invention;

[0027] Figure 2 It is a schematic diagram of the open state of the second flow channel provided by the embodiment of the present invention;

[0028] In the figure: 1. Nozzle head; 2. First flow channel; 3. Second flow channel; 4. Spool; 5. Valve body; 6. Valve plate; 7. Rotating shaft; 8. Damping mechanism; Detailed Embodiments

[0029] It should be noted that the following detailed description is illustrative and is intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention pertains. In addition, it should also be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0030] Embodiment 1

[0031] As Figure 1 、 Figure 2 shown, this embodiment proposes a containment nozzle based on active and passive scenarios, including: a housing, a valve core 4, a valve plate 6, and a damping mechanism 8; the housing has a cavity, and the cavity has a fluid inlet and a fluid outlet; the valve core 4 is located in the cavity at one end of the fluid outlet of the housing and divides the cavity into a first flow channel 2 and a second flow channel 3; the valve plate 6 is located in the cavity at one end of the fluid inlet of the housing, and the head end of the valve plate 6 is rotatably connected to the housing; one end of the damping mechanism 8 is installed on the cavity wall of the housing, and the other end is connected to the valve plate 6 and can connect the end of the valve plate 6 to the valve plate 6.

[0032] This nozzle forms a fluid channel through the housing. The valve core 4 divides the cavity into a first flow channel 2 and a second flow channel 3. The valve plate 6 is arranged at the inlet end in a rotational connection manner, and the damping mechanism 8 is connected to the valve plate 6 in a mechanical connection manner to realize linkage with the valve plate 6, and automatically adjusts the opening degree of the valve plate 6 through the hydrodynamic characteristics of the medium. When the medium flow rate changes, the valve plate 6 is in dynamic equilibrium under the fluid impact force and the acting force of the damping mechanism 8, realizing intelligent switching control of the double flow channels.

[0033] The housing includes a valve body 5 and a nozzle head 1. The cavity includes a straight cavity section and an inclined cavity section. The inclined cavity section is located at one end of the fluid inlet of the housing, and the straight cavity section is located at one end of the fluid outlet of the housing. The inclined cavity section is arranged on the fluid inlet side to form an inclined guiding surface, thereby realizing opening the valve plate 6 and adjusting the opening degree of the valve plate 6 under the impact of the medium. The straight cavity section extends axially on the outlet side. This structure enables the valve plate 6 to form an angular installation space in the inclined cavity section and provides a symmetric arrangement condition for the radial separation of the valve core 4.

[0034] The spool 4 is arranged in the straight cavity section of the cavity, and the valve plate 6 is arranged in the inclined cavity section of the cavity. The spool 4 is fixedly installed at the axial position of the straight cavity section. The flow channel is divided into two independent channels by the extended partition plate, ensuring that the medium can flow along a predetermined path when flowing through the straight cavity section. The valve plate 6 is arranged in the inclined cavity section, at one end of the fluid inlet. The rotation plane of the valve plate 6 forms an angle with the medium flow direction, and it can be impacted by the impact force when the medium enters the nozzle for the first time, thereby controlling the opening and closing of the flow channel, ensuring that the medium can accurately flow into the corresponding flow channel according to the requirements, guaranteeing the fluid continuity during the flow channel switching process, and achieving precise control of the medium flow direction by the nozzle.

[0035] The first end of the valve plate 6 is the end close to the fluid inlet. The first end of the valve plate 6 is rotatably installed at the fluid inlet of the housing through the rotating shaft 7. This connection method enables the valve plate 6 to rotate flexibly around the rotating shaft 7, adjust its own angle according to the magnitude of the impact force of the medium, so as to achieve the opening and closing control of the flow channel. The setting of the rotating shaft 7 provides a stable support point for the rotation of the valve plate 6, ensuring the reliability and stability of the valve plate 6 during the working process. At the same time, it is also convenient for the installation and maintenance of the valve plate 6, improving the service life and maintenance convenience of the nozzle.

[0036] When the valve plate 6 is attached to the spool 4, the second flow channel 3 is closed, and the fluid inlet is only connected to the first flow channel 2. This means that when the medium flow rate is small, such as in the passive scenario, the valve plate 6 remains in the closed state under the action of the damping mechanism 8, and the medium can only flow through the defined cross-section of the first flow channel 2, forming a restricted flow state, ensuring that the necessary fluid kinetic energy is maintained under low flow rate conditions, preventing flow stagnation, avoiding problems such as flow dispersion and poor flow caused by too many flow channels, and improving the working effect and reliability of the nozzle in the passive scenario.

[0037] The rotating shaft 7 and the damping mechanism 8 are installed on the same side wall of the cavity. The rotating shaft 7 and the damping mechanism 8 are arranged on the same side to form a couple action system. When the valve plate 6 is forced to rotate, the damping mechanism 8 generates a reverse torque. This arrangement optimizes the force distribution of the mechanism and at the same time avoids the influence of the damping mechanism 8 on the flowing medium.

[0038] In a specific embodiment, the damping mechanism 8 is a spring. One end of the spring is connected to the cavity wall corresponding to the second flow channel 3, and the other end abuts against the valve plate 6. Under the initial condition, the spring is in a compressed state.

[0039] When the medium impacts the valve plate 6, the impact force received by the valve plate 6 needs to overcome the elastic force of the spring to open. In the passive scenario, the medium flow rate is small, and the impact force is not sufficient to overcome the spring elastic force, so the valve plate 6 remains closed; while in the active scenario, the medium flow rate is large, and the impact force is sufficient to overcome the spring elastic force, and the valve plate 6 is opened, enabling the medium to flow out from both the first flow channel 2 and the second flow channel 3 simultaneously. The design of this spring damping mechanism 8 is simple and reliable, and it can effectively automatically adjust the opening degree of the valve plate 6 according to the size of the medium flow rate, meeting the working requirements of the nozzle in different scenarios.

[0040] In another embodiment, the damping mechanism 8 is an elastic sheet. One end of the elastic sheet is installed on the cavity wall, and the other end of the elastic sheet is attached to the back of the valve plate 6, pushing the valve plate 6 towards the valve core 4.

[0041] The elastic sheet generates a thrust force through its own elastic deformation, causing the valve plate 6 to remain in contact with the valve core 4 and closing the second flow channel 3 when there is no medium impact or the impact force is small. When the medium impact force increases to a certain extent, the valve plate 6 overcomes the thrust force of the elastic sheet and opens outward, connecting the fluid inlet to the second flow channel 3. This elastic sheet damping mechanism 8 has the characteristics of a compact structure and sensitive response, and can quickly adjust the position of the valve plate 6 when the medium flow rate changes, ensuring that the working state of the nozzle matches the actual requirements, and improving the adaptability and response speed of the nozzle.

[0042] Of course, it can be understood that the rotating shaft 7 and the damping mechanism 8 can also be installed on different side walls of the cavity. The damping mechanism 8 is a spring. One end of the spring is connected to the cavity wall corresponding to the first flow channel 2, and the other end abuts against the valve plate 6. Under the initial condition, the spring is in a stretched state. The tension spring mechanism arranged on different sides forms a symmetric force system, and the pulling direction of the spring interacts with the rotation direction of the valve plate 6. The valve plate 6 needs to overcome the pulling force of the spring to open. In the installation method on different side walls, the pulling force of the spring can more effectively balance the impact force received by the valve plate 6, making the opening and closing actions of the valve plate 6 smoother and more precise, further improving the stability and reliability of the nozzle under complex working conditions, and ensuring the precise control of the medium flow.

[0043] Embodiment 2

[0044] This embodiment provides a working method for the containment nozzle based on active and passive scenarios as described in Embodiment 1, including:

[0045] In the passive scenario, the medium impact force is small and cannot overcome the resistance of the damping mechanism 8, so the valve plate 6 remains in the closed state, and the medium only flows out from the first flow channel 2, ensuring the stable flow of the medium in the passive scenario.

[0046] In the active scenario, the impact force of the medium is large enough to overcome the resistance of the damping mechanism 8, the valve plate 6 is opened, the fluid inlet is communicated with the second flow channel 3, and the medium flows out from both the first flow channel 2 and the second flow channel 3 simultaneously. Moreover, the opening degree of the valve plate 6 can be adjusted in real time according to the medium flow rate, achieving the adaptive adjustment of the nozzle in different scenarios, improving the versatility and flexibility of the nozzle, meeting the usage requirements of the containment spray system of the nuclear power plant in the case of the combination of active and passive modes, enhancing the safety and reliability of the in-reactor operation, saving costs at the same time, and meeting the economic requirements.

[0047] Although the specific implementation manners of the present invention are described above in conjunction with the accompanying drawings, it is not a limitation to the protection scope of the present invention. Those skilled in the art should understand that, based on the technical solutions of the present invention, various modifications or deformations that can be made by those skilled in the art without creative efforts are still within the protection scope of the present invention.

Claims

1. A containment nozzle based on active and passive scenarios, characterized in that: include: Housing, valve core, valve plate and damping mechanism; The housing has a cavity having a fluid inlet and a fluid outlet; The valve core is located in a cavity at one end of the fluid outlet of the housing, and divides the cavity into a first flow channel and a second flow channel; The valve plate is located in a cavity at one end of the fluid inlet of the housing, and the head end of the valve plate is rotatably connected to the housing; One end of the damping mechanism is mounted on the cavity wall of the housing, and the other end is connected to the valve sheet, and the end of the valve sheet can be overlapped onto the valve sheet.

2. The containment nozzle based on active and passive scenarios according to claim 1, characterized in that: The housing comprises a valve body and a nozzle head, the cavity comprises a straight cavity section and an oblique cavity section, the oblique cavity section is located at a fluid inlet end of the housing, and the straight cavity section is located at a fluid outlet end of the housing.

3. The containment nozzle based on active and passive scenarios according to claim 2, characterized in that: The valve core is arranged in the straight cavity section of the cavity, and the valve sheet is arranged in the inclined cavity section of the cavity.

4. The containment nozzle based on active and passive scenarios according to claim 3, characterized in that: The head end of the valve plate is close to the fluid inlet, and the head end of the valve plate is rotatably mounted at the fluid inlet of the shell through a rotating shaft.

5. The containment nozzle based on active and passive scenarios according to claim 4, characterized in that: When the valve sheet is overlapped onto the valve core, the second flow channel is closed, and the fluid inlet is only connected to the first flow channel.

6. The containment nozzle based on active and passive scenarios according to claim 5, characterized in that: The rotating shaft and the damping mechanism are mounted on the same side wall of the cavity.

7. The containment nozzle based on active and passive scenarios according to claim 6, characterized in that: The damping mechanism is a spring, one end of which is connected to the cavity wall corresponding to the second flow channel, and the other end of which abuts against the valve plate. Under initial conditions, the spring is in a compressed state.

8. The containment nozzle based on active and passive scenarios according to claim 6, characterized in that: The damping mechanism is an elastic sheet, one end of which is mounted on the cavity wall, and the other end of which is attached to the back of the valve sheet to push the valve sheet toward the valve core.

9. The containment nozzle based on active and passive scenarios according to claim 5, characterized in that: The rotating shaft and the damping mechanism are installed on different side walls of the cavity. The damping mechanism is a spring. One end of the spring is connected to the cavity wall corresponding to the first flow channel, and the other end abuts against the valve plate. Under initial conditions, the spring is in a stretched state.

10. A method for operating a containment nozzle in active and passive scenarios according to any one of claims 1 to 9, characterized in that: include: In a passive scenario, the impact force of the medium cannot overcome the resistance of the damping mechanism to open the valve plate, the tail end of the valve plate abuts against the valve core, and the medium flows out from the fluid inlet through the first flow channel and out from the fluid outlet; In the active scenario, the impact force of the medium can overcome the resistance of the damping mechanism and open the valve plate, so that the fluid inlet is connected to the second flow channel, and the medium flows out from the fluid inlet through the first flow channel and the second flow channel and out of the fluid outlet, and the opening of the valve plate can be adjusted in real time according to the medium flow rate.

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