A radial movable fuel transient irradiation device applicable to research reactors

Abstract

This application belongs to the technical field of research reactor irradiation, and specifically relates to a radial mobile fuel transient irradiation device applicable to research reactors. It includes an irradiation container, an in-pile irradiation device, a moving mechanism, and a limiting mechanism; the irradiation container has an opening; one end of the in-pile irradiation device is located inside the irradiation container, and the other end is located outside the irradiation container; the moving mechanism is arranged on the irradiation container and connected to the in-pile irradiation device to drive the in-pile irradiation device to move in the opening in a preset direction; the limiting mechanism is arranged inside the irradiation container and is movably matched with the in-pile irradiation device, and the in-pile irradiation device has a moving direction along the preset direction relative to the limiting mechanism. This application can achieve the radial displacement of the in-pile irradiation device without relying on the environment of the pool-type research reactor, so that it can be applicable to the fuel transient irradiation test of pool-type / non-pool-type research reactors.

Description

Technical Field

[0001] This application relates to the technical field of research reactor irradiation technology. Specifically, it relates to a radial mobile fuel transient irradiation device applicable to a research reactor. Background Art

[0002] The performance of pressurized water reactor fuel elements is directly related to the safety and economy of the reactor. Conducting in-pile irradiation tests on fuel elements is a crucial part of the research and design of fuel elements. The power transient irradiation test of fuel elements is generally carried out on a research reactor using a dedicated in-pile power transient irradiation device; by changing the power of the fuel element in a short time, the performance parameters and safety margins of the fuel element are verified. To conduct a power transient irradiation test on pressurized water reactor fuel elements in a research reactor, some foreign research reactors, such as those in Finland, Sweden, Japan, etc., use gas ( 3 He gas, BF3 gas) circuits as power adjustment devices for fuel elements; while the OSIRIS reactor in France and the HFR reactor in the Netherlands use the method of an overall mobile in-pile irradiation device to effectively adjust the irradiation power of the test fuel element. The above methods using an overall mobile in-pile irradiation device all utilize the wide cooling water reflector area of the pool-type reactor to arrange a movable in-pile device, and use the change in the distance between the in-pile irradiation device and the core active area to achieve the power change of the test fuel element; this method is very suitable for the characteristics of the pool-type water-cooled research reactor, but it is difficult to be applied to non-pool-type research reactors. Summary of the Invention

[0003] This application provides a radial mobile fuel transient irradiation device applicable to a research reactor to solve the problems in the background art.

[0004] This application is achieved through the following technical solutions:

[0005] A radial mobile fuel transient irradiation device applicable to a research reactor, comprising:

[0006] An irradiation container having an opening;

[0007] An in-pile irradiation device, one end of which is located inside the irradiation container and the other end is located outside the irradiation container;

[0008] A moving mechanism disposed on the irradiation container and connected to the in-pile irradiation device to drive the in-pile irradiation device to move in a preset direction within the opening;

[0009] A limiting mechanism disposed inside the irradiation container and movably cooperating with the in-pile irradiation device, and the in-pile irradiation device has a moving direction along the preset direction relative to the limiting mechanism.

[0010] In some alternative embodiments, the moving mechanism includes:

[0011] A first fixing member, which is relatively fixed to the irradiation container;

[0012] A first moving member, which is movably engaged with the first fixing member and connected to the in-core irradiation device;

[0013] A transmission assembly, which is connected to the first moving member to drive the first moving member to move on the first fixing member in the preset direction;

[0014] A movement control device, which is connected to the transmission assembly to control the operation of the transmission assembly.

[0015] In some alternative embodiments, a limiter is arranged on the first fixing member.

[0016] In some alternative embodiments, the limiting mechanism includes:

[0017] A second moving member, which is connected to the in-core irradiation device;

[0018] A second fixing member, which is movably engaged with the second moving member so that the in-core irradiation device can drive the second moving member to move on the second fixing member in the preset direction. The second fixing member is connected to the bottom of the irradiation container and is located between the second moving member and the in-core irradiation device.

[0019] In some alternative embodiments, the second moving member is connected to the in-core irradiation device through a tensioning member.

[0020] In some alternative embodiments, a shielding cover plate is connected to the in-core irradiation device. The shielding cover plate is configured such that when the in-core irradiation device moves to the limit stroke, in the length direction of the in-core irradiation device, the shielding cover plate can cover the opening.

[0021] In some alternative embodiments, the in-core irradiation device includes:

[0022] A first housing, which is connected to the moving mechanism and has a first cooling medium inlet;

[0023] A second housing, which is inserted into the first housing. A medium flow channel is formed between the second housing and the inner wall of the first housing. The second housing has an assembly interface located inside the first housing and a first cooling medium outlet located outside the first housing;

[0024] Component installation box, the component installation box is connected to the assembly interface through an intermediate joint, the component connection box has an installation cavity that communicates the medium flow channel with the inside of the second housing, and the installation cavity is used to install a fuel assembly;

[0025] Heat exchanger, the heat exchanger is arranged inside the second housing, and the heat exchanger has a second cooling medium inlet and a second cooling medium outlet respectively located outside the first housing.

[0026] In some alternative embodiments, the heat exchanger includes a plurality of spiral heat transfer tubes, and the plurality of spiral heat transfer tubes are wound around each other to form a cylindrical heat exchange tube bundle.

[0027] In some alternative embodiments, the spiral heat transfer tube is configured as a double spiral heat transfer tube.

[0028] In some alternative embodiments, a plurality of self-powered neutron detectors are arranged on the outer wall of the component installation box, wherein the self-powered neutron detectors correspond to the position of the center plane of the active area of the fuel assembly.

[0029] In some alternative embodiments, thermocouples are respectively arranged at the front and rear ends of the component installation box in the flow direction of the first cooling medium.

[0030] Compared with the prior art, the present application has the following advantages and beneficial effects:

[0031] A radial mobile fuel transient irradiation device applicable to a research reactor provided by the present application, through the arrangement of an irradiation container and a moving mechanism and a limiting mechanism on the irradiation container, the in-pile irradiation device in the irradiation container can move in a preset direction driven by the moving mechanism, and the movement direction of the in-pile irradiation device can be ensured to be stable through the limiting effect of the limiting mechanism during the movement process, so that the distance between the in-pile irradiation device and the core active area can be accurately changed as expected, and further the power adjustment of the test fuel assembly can be realized; wherein, the movement of the in-pile irradiation device and the installation of the overall device do not strictly depend on a research reactor with a pool type structure, so it can be applicable to research reactors with a pool type or non-pool type structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0033] Figure 1 Structural schematic diagram of a radial mobile fuel transient irradiation device applicable to a research reactor provided by an embodiment of the present application;

[0034] Figure 2 Schematic structural diagram of the in-pile irradiation device provided by the embodiment of the present application;

[0035] Figure 3 Schematic simplified diagram of the cooperation between the in-pile irradiation device and the moving mechanism provided by the embodiment of the present application;

[0036] Figure 4 Schematic simplified diagram of the cooperation between the in-pile irradiation device and the limiting mechanism provided by the embodiment of the present application;

[0037] Figure 5 Schematic structural diagram of the heat exchanger provided by the embodiment of the present application.

[0038] Marks in the drawings and corresponding component names:

[0039] 1 - Irradiation container, 2 - Container flange, 3 - First fixing member, 4 - Limiter, 5 - First moving member, 6 - Support member, 7 - Moving control device, 8 - Shielding cover plate, 9 - In-pile irradiation device, 10 - Connecting member, 11 - Second moving member, 12 - Second fixing member, 901 - First housing, 902 - Second housing, 903 - Intermediate joint, 904 - Component installation box, 905 - Fuel assembly, 906 - Instrument tube, 907 - Heat exchanger, 908 - First cooling medium inlet, 909 - First cooling medium outlet, 910 - Second cooling medium inlet, 911 - Second cooling medium outlet, 912 - Thermocouple, 913 - Self-powered neutron detector, 914 - Medium flow channel, 915 - Installation cavity, 9071 - Double spiral heat transfer tube. Detailed implementation manners

[0040] To make the objectives, technical solutions and advantages of the present application clearer and more understandable, the present application will be further described in detail below in combination with the embodiments and the drawings. The illustrative embodiments and descriptions thereof of the present application are only used to explain the present application and shall not be construed as a limitation to the present application.

[0041] In the following description, a large number of specific details are set forth in order to provide a thorough understanding of the present application. However, it is obvious to those of ordinary skill in the art that: the present application does not have to adopt these specific details. In other embodiments, well-known structures, circuits, materials or methods are not specifically described in order to avoid obscuring the present application.

[0042] Throughout the specification, references to "one embodiment", "an embodiment", "one example", or "an example" mean that a particular feature, structure, or characteristic described in connection with the embodiment or example is included in at least one embodiment of the present application. Thus, the phrases "one embodiment", "an embodiment", "one example", or "an example" appearing throughout the specification do not necessarily all refer to the same embodiment or example. Additionally, the particular features, structures, or characteristics may be combined in any suitable combination and / or sub-combination in one or more embodiments or examples. Further, those of ordinary skill in the art should understand that the diagrams provided herein are for illustrative purposes only and are not necessarily drawn to scale. The term "and / or" used herein includes any and all combinations of one or more of the associated listed items.

[0043] In the description of the present application, the orientation or positional relationship indicated by terms such as "front", "rear", "left", "right", "upper", "lower", "vertical", "horizontal", "high", "low", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the protection scope of the present application.

[0044] As Figure 1 shown, an embodiment of the present application provides a radial movable fuel transient irradiation device applicable to a research reactor, including an irradiation container 1, an in-pile irradiation device 9, a moving mechanism, and a limiting mechanism.

[0045] The irradiation container 1 has an opening, so that the irradiation container 1 as a whole has a barrel-shaped structure; the cross-sectional shape of the irradiation container 1 may not be limited, and it can be adaptively designed according to the specific installation environment. Considering the convenience of manufacture and the ability to provide a certain internal installation / movement space, in actual implementation, the cross-section of the irradiation container 1 may be square, and the four corner points of the square are configured as rounded corner structures; a container flange 2 may be configured at the opening of the irradiation container 1 to facilitate connection to the fixed structure of the research reactor pressure vessel or the pool-type research reactor. At the same time, the flange connection structure can provide a certain degree of sealing, so that when the irradiation container 1 is connected to the fixed structure of the research reactor pressure vessel or the pool-type research reactor, a relatively airtight space without the research reactor coolant can be formed, and this airtight space can accommodate the in-pile irradiation device 9 and receive neutron irradiation from the core of the research reactor. Among them, the cross-sectional shape of the irradiation container 1 may be a rectangle. When fixing the irradiation container 1, the long side of the irradiation container 1 can be parallel to the radial direction of the core center.

[0046] The in-pile irradiation device 9 has a first end and a second end. Inside the in-pile irradiation device 9, it is used to cooperate with the fuel assembly 905 to achieve the irradiation process. The fuel assembly 905 can be located at a position close to the first end in the in-pile irradiation device 9. The first end of the in-pile irradiation device 9 is inserted into the irradiation container 1 through an opening. The second end of the in-pile irradiation device 9 is located outside the irradiation container 1, and the second end of the in-pile irradiation device 9 is usually used as the input end of, for example, a cooling medium.

[0047] The moving mechanism is arranged on the irradiation container 1. The moving mechanism can be fixedly connected to the irradiation container 1, so that the moving mechanism can remain relatively fixed with the irradiation container 1. The moving mechanism is also connected to the in-pile irradiation device 9 to drive the in-pile irradiation device 9 to move in the opening in a preset direction.

[0048] The limiting mechanism is arranged inside the irradiation container 1 and is movably matched with the in-pile irradiation device 9. The in-pile irradiation device 9 has a moving direction along the preset direction relative to the limiting mechanism. Thus, the limiting mechanism forms a limit on the in-pile irradiation device 9, and the in-pile irradiation device 9 can move stably in the preset direction.

[0049] The radial mobile fuel transient irradiation device applicable to a research reactor provided by the embodiment of the present application, through the arrangement of the irradiation container 1 and the moving mechanism on the irradiation container 1, the moving mechanism can drive the in-pile irradiation device 9 to move in the irradiation container 1 in a preset direction. Thus, the distance between the in-pile irradiation device 9 and the core active zone is changed, and the power of the test fuel element is adjusted. The installation of the irradiation container 1 and the movement of the in-pile irradiation device 9 do not completely depend on the special environment of the pool-type research reactor. Thus, the radial mobile fuel transient irradiation device applicable to a research reactor provided by the embodiment of the present application can be applied to the pool-type / non-pool-type research reactor environment.

[0050] In some alternative embodiments, reference may be made to Figure 1 and Figure 3 , the moving mechanism may specifically include a first fixing member 3, a first moving member 5, a transmission assembly, and a movement control device 7.

[0051] The first fixing member 3 is relatively fixed to the irradiation container 1. The first fixing member 3 can achieve the relative fixation of the two by being fixedly connected to the irradiation container 1, or by connecting the first fixing member 3 to other fixing facilities / structures, and the fixing facilities / structures are relatively fixed to the irradiation container 1. Thus, the first fixing member 3 can remain relatively fixed with the irradiation container 1. When the container flange 2 is configured on the irradiation container 1, the first fixing member 3 can be connected to the container flange 2. The first fixing member 3 can be configured as a groove slide rail. The number of the first fixing members 3 can be set to two and are respectively connected to the container flange 2 structures on both sides of the opening. Among them, the length direction of the groove slide rail is parallel to the preset direction.

[0052] The first moving member 5 is movably engaged with the first fixed member 3, so that the first moving member 5 can move relative to the first fixed member 3. For example, when the first fixed member 3 is configured as a groove slide rail, the first moving member 5 can be configured as a first roller or a first slider. Considering that the first moving member 5 will be subject to frictional resistance during movement, in actual implementation, the first moving member 5 can be configured as a first roller to ensure the smooth movement of the first moving member 5. The first moving member 5 and the in-core irradiation device 9 can be fixedly connected through a support member 6, wherein the first moving member 5 is rotatably connected to the support member 6, so that the first moving member 5 can freely rotate on the support member 6, and thus the first moving member 5 can drive the in-core irradiation device 9 to perform synchronous movement.

[0053] The transmission assembly is connected to the first moving member 5 to drive the first moving member 5 to move in a preset direction on the first fixed member 3. The transmission assembly can usually be configured as a rotating mechanism. For example, the transmission mechanism can be configured as a motor, and the transmission mechanism is in transmission cooperation with the first roller to drive the first roller to rotate, so as to realize the relative movement of the first moving member 5 on the first fixed member 3. The transmission assembly can also be configured as a reciprocating mechanism. Driven by the transmission assembly, the first moving member 5 can translate on the first fixed member 3. When the first moving member 5 is configured as a first roller, driven by the transmission assembly, the first moving member 5 can freely roll on the first fixed member.

[0054] The movement control device 7 is connected to the transmission assembly to control the operation of the transmission assembly.

[0055] The stop position of the first moving member 5 on the first fixed member 3 can be achieved through the movement control device 7. For example, when the transmission assembly is driven by a motor, the movement control device 7 can control the number of revolutions of the motor to achieve the positioning of the first moving member 5 on the first fixed member 3 to determine the movement stroke of the first moving member 5. However, after the first moving member 5 moves on the first fixed member 3 for a long time, certain errors will accumulate. Therefore, when the movement control device 7 is used to control the stop position of the first moving member 5, the position error of the first moving member 5 will become larger and larger. Therefore, in actual implementation, we prefer to control the stop position of the first moving member 5 by mechanical limiting. For example, in some alternative embodiments, reference can be continued to Figure 1, a limiter 4 is arranged on the first fixing member 3. The limiter 4 can usually be configured as a rubber anti-collision block. By arranging two limiters 4 spaced apart along the length of the first fixing member 3, the movement stroke of the first moving member 5 can be determined. When the first moving member 5 collides with the limiter 4, the movement of the transmission mechanism can be stopped by detecting the motor stall in the transmission mechanism through the movement control device 7. Of course, in other embodiments, the limiter 4 can also be configured as a travel switch. After the travel switch collides with the first moving member 5, it can form a mechanical limit on the first moving member 5. At the same time, the travel switch can send a signal to the movement control device 7 to immediately control the transmission mechanism to stop moving, reducing / avoiding the situation of motor stall.

[0056] In some alternative embodiments, reference may be made together to Figure 1 and Figure 4 , the limiting mechanism may include a second moving member 11 and a second fixing member 12.

[0057] The second moving member 11 is connected to the in-pile irradiation device 9, so that when the in-pile irradiation device 9 moves along a preset direction, the second moving member 11 can be driven to move synchronously. The second moving member 11 can be connected to the bottom of the in-pile irradiation device 9 through a connecting member 10. That is, after the in-pile irradiation device 9 is installed, there is a spacing between the second moving member 11 and the in-pile irradiation device 9 in the direction from the bottom to the opening of the irradiation container 1. Thus, in the direction perpendicular to the direction from the bottom to the opening (for example, the overall shape of the in-pile irradiation device 9 is usually cylindrical, and the radial direction of the in-pile irradiation device 9 is this direction here), the second moving member 11 will not block the in-pile irradiation device 9.

[0058] The second fixing member 12 is movably matched with the second moving member 11 so that the in-pile irradiation device 9 can drive the second moving member 11 to move on the second fixing member 12 in a preset direction. The second fixing member 12 is connected to the bottom of the irradiation container 1. As described above, when the transmission mechanism is configured as a motor and is in transmission cooperation with the first roller, the first roller is connected to the in-pile irradiation device 9 through a support member 6. The in-pile irradiation device 9 has a risk of shaking in the irradiation container 1. Therefore, the second fixing member 12 is arranged between the second moving member 11 and the in-pile irradiation device 9. That is, during the shaking process of the in-pile irradiation device 9, the position of the second moving member 11 in the length direction of the in-pile irradiation device 9 will change. By arranging the second fixing member 12 between the second moving member 11 and the in-pile irradiation device 9, the second fixing member 12 can limit the position of the second moving member 11 in the length direction of the in-pile irradiation device 9, that is, the purpose of preventing the in-pile irradiation device 9 from shaking is achieved.

[0059] In actual implementation, the second fixing member 12 can be configured as two long horizontal bars. The length direction of the long horizontal bars is parallel to the bottom of the irradiation container 1 and parallel / coincident with the preset direction. The long horizontal bars can be fixedly connected to the bottom of the irradiation container 1 through connecting vertical bars. The two long horizontal bars are arranged in parallel at intervals, and the space between the two long horizontal bars is used to avoid the connecting member 10. The second moving member 11 is in contact with both long horizontal bars at the same time. The second moving member 11 can be configured as a second roller. Thus, when the in-core irradiation device 9 moves, the second moving member 11 can roll on the two long horizontal bars.

[0060] Due to the assembly error between the first moving member 5 and the first fixing member 3, during the movement of the first moving member 5, the second moving member 11 may not form effective contact with the second fixing member 12 in real time, that is, the in-core irradiation device 9 may experience intermittent shaking. Therefore, in some alternative embodiments, the second moving member 11 is connected to the in-core irradiation device 9 through a tensioning member. The tensioning member can pre-tension the second moving member 11, so that the second moving member 11 can form effective contact with the second fixing member 12 in real time under the tensioning action of the tensioning member, thereby avoiding the possible shaking phenomenon of the in-core irradiation device 9 during operation. At the same time, the setting of the tensioning member can also provide a certain buffer space for the in-core irradiation device 9, that is, the in-core irradiation device 9 can move slightly in its length direction, so as to avoid excessive force exerted by the in-core irradiation device 9 on the second fixing member 12 in its length direction and cause structural damage. Generally, when the in-core irradiation device 9 has a movement tendency in its own length direction, the force it exerts on the second fixing member 12 is greater than the force it exerts on the second fixing member 12 when the in-core irradiation device 9 has a shaking tendency, that is, the force required to restrain the in-core irradiation device 9 from moving along its own length direction is greater than the force required to restrain the in-core irradiation device 9 from shaking. Therefore, in actual implementation, the number of tensioning members can be set to two, and each tensioning member is configured such that the tension force it provides forms an angle with the length direction of the in-core irradiation device 9. Thus, a single tensioning member can restrain the shaking of the in-core irradiation device 9, and the resultant force that the two tensioning members can provide in the length direction of the in-core irradiation device 9 can restrain the in-core irradiation device 9 from moving along its own length direction. In actual implementation, the tensioning member can be configured as a helical spring.

[0061] In some alternative embodiments, reference can be made to Figure 1 , a shielding cover plate 8 is connected to the irradiation device. The shielding cover plate 8 can adopt a plate-like structure with a stainless steel coating and a lead core. The shielding cover plate 8 is configured such that when the in-core irradiation device 9 moves to the limit stroke, in the length direction of the in-core irradiation device 9, the shielding cover plate 8 can cover the opening, so that the shielding cover plate 8 can effectively reduce the radioactive hazard caused by the neutron and gamma ray leakage from the core active area.

[0062] In some alternative embodiments, reference can be made toFigure 2 , the in-pile irradiation device 9 may include a first housing 901, a second housing 902, a component mounting box 904, and a heat exchanger 907.

[0063] The first housing 901 may be configured as a circular pressure tube. Both axial ends of the first housing 901 are sealed structures. A first cooling medium inlet 908 is provided on the side wall of the first housing 901. The first housing 901 is connected to a moving mechanism, so that the moving mechanism can drive the first housing 901 to move the in-pile irradiation device 9 in a preset direction.

[0064] The second housing 902 may be configured as a circular tube. One axial end of the second housing 902 is a sealed structure, and the other end is an open structure as an assembly interface. The open structure of the second housing 902 is inserted into the first housing 901 from one axial end face of the first housing 901. The second housing 902 is coaxially arranged with the first housing 901. The outer diameter of the second housing 902 is smaller than the inner diameter of the first housing 901, so that a medium flow channel 914 communicating with the first cooling medium inlet 908 can be formed between the outer wall of the second housing 902 and the inner wall of the first housing 901. A first cooling medium outlet 909 located outside the first housing 901 is provided on the side wall of the second housing 902. A sealed connection may be adopted between the outer wall of the second housing 902 and the end of the first housing 901 to ensure a good sealing effect.

[0065] The component mounting box 904 may be a square tube structure as a whole. The inner cavity of the component mounting box 904 serves as an installation cavity 915 to install the fuel assembly 905. One end of the installation cavity 915 communicates with the medium flow channel 914. The other end of the component mounting box 904 is connected to the assembly interface through an intermediate joint 903. The intermediate joint 903 may be configured as an open communication device, where the end with a larger diameter communicates with the assembly interface of the first housing 901, and the end with a smaller diameter communicates with the component mounting box 904. The end with a smaller diameter may be configured to fit the shape of the fuel assembly 905 to cooperate with the fuel assembly 905 to ensure the stability of the fuel assembly 905.

[0066] The heat exchanger 907 is disposed in the second housing 902. The heat exchanger 907 has a second cooling medium inlet 910 and a second cooling medium outlet 911 respectively located outside the first housing 901.

[0067] In the working state, the first cooling medium enters the medium flow channel 914 from the first cooling medium inlet 908, reaches the inside of the second housing 902 after passing through the component mounting box 904, and the second cooling medium enters the heat exchanger 907 from the second cooling medium inlet 910. Thus, the heat exchanger 907 can achieve the purpose of heat exchange for the first cooling medium in the second housing 902. The first cooling medium after heat exchange flows out from the first cooling medium outlet 909, and the second cooling medium flows out from the second cooling medium outlet 911.

[0068] In some alternative embodiments, refer to Figure 2 , and an instrument tube 906 is further provided in the second housing 902. The instrument tube 906 can lead out the first cooling medium in the second housing 902 to measure physical parameters such as the pressure and temperature of the first cooling medium.

[0069] In some alternative embodiments, the heat exchanger 907 includes a plurality of spiral heat transfer tubes, and the plurality of spiral heat transfer tubes are wound around each other to form a cylindrical heat exchange tube bundle. Specifically, when implemented, both ends of a single spiral heat transfer tube sequentially pass through the second housing 902 and the first housing 901 to be located outside the first housing 901. The spiral heat transfer tube is hermetically connected to the first housing 901 and the second housing 902 to prevent the first cooling medium in the second housing 902 and the medium flow channel 914 from mixing. The arrangement of the spiral heat transfer tubes can provide a longer path for the second cooling medium, so that the residence time of the second cooling medium in the second housing 902 is longer, ensuring that the heat exchanger 907 has a better heat exchange effect.

[0070] In some alternative embodiments, refer to Figure 5 , and the spiral heat transfer tube is configured as a double spiral heat transfer tube 9071. The arrangement of the double spiral heat transfer tube 9071 can further lengthen the path of the first cooling medium in the second housing 902, thereby achieving a better heat exchange effect.

[0071] In some alternative embodiments, refer to Figure 2 , and a plurality of self-powered neutron detectors 913 are provided on the outer wall of the component mounting box 904. Among them, the self-powered neutron detectors 913 correspond to the central plane position of the active area of the fuel assembly 905, so as to monitor the thermal neutron fluence rate and its change at the test fuel assembly 905, and further monitor the power change of the fuel assembly 905 during the fuel transient test process.

[0072] In some alternative embodiments, refer to Figure 2, in the flow direction of the first cooling medium, thermocouples 912 are respectively arranged at the front and rear ends of the component installation box 904, so as to measure the temperature of the first cooling medium. Through the measured temperature difference of the first cooling medium and the flow rate of the first cooling medium measured by an external system connected to the device, the online measurement of the heat release power of the test fuel assembly 905 can be realized.

[0073] In summary, the radial mobile fuel transient irradiation device applicable to a research reactor provided by the embodiment of the present application adopts the integrated in-pile irradiation device 9 scheme with the pressure tube built-in spiral tube heat exchanger 907, which can effectively simplify the design of the out-of-pile loop system.

[0074] Isolated by the irradiation container 1, and the radial movement of the in-pile irradiation device 9 is realized by using the moving mechanism and the limiting mechanism, which can be used for the fuel transient test of a research reactor with a pool type or non-pool type structure, and expands the application range of the radial mobile fuel transient test scheme.

[0075] The specific embodiments described above have further elaborated on the purpose, technical solutions and beneficial effects of the present application. It should be understood that the above description is only the specific embodiments of the present application and is not used to limit the protection scope of the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A radial mobile fuel transient irradiation device applicable to a research reactor, characterized in that Comprising: An irradiation container (1), the irradiation container (1) having an opening; An in-core irradiation device (9), one end of the in-core irradiation device (9) being located inside the irradiation container (1) and the other end being located outside the irradiation container (1); A moving mechanism, the moving mechanism being arranged on the irradiation container (1) and connected to the in-core irradiation device (9) to drive the in-core irradiation device (9) to move in a preset direction within the opening; A limiting mechanism, the limiting mechanism being arranged inside the irradiation container (1) and being movably matched with the in-core irradiation device (9), the in-core irradiation device (9) having a moving direction along the preset direction relative to the limiting mechanism; Wherein, the moving mechanism includes: A first fixing member (3), the first fixing member (3) being relatively fixed to the irradiation container (1); A first moving member (5), the first moving member (5) being movably matched with the first fixing member (3) and connected to the in-core irradiation device (9); A transmission assembly, the transmission assembly being connected to the first moving member (5) to drive the first moving member (5) to move in the preset direction on the first fixing member (3); A moving control device (7), the moving control device (7) being connected to the transmission assembly to control the operation of the transmission assembly; Wherein, the limiting mechanism includes: A second moving member (11), the second moving member (11) being connected to the in-core irradiation device (9) through a tensioning member; A second fixing member (12), the second fixing member (12) being movably matched with the second moving member (11) so that the in-core irradiation device (9) can drive the second moving member (11) to move in the preset direction on the second fixing member (12), the second fixing member (12) being connected to the bottom of the irradiation container (1), and the second fixing member (12) being located between the second moving member (11) and the in-core irradiation device (9).

2. The radial mobile fuel transient irradiation device applicable to a research reactor according to claim 1, characterized in that A limiter (4) is arranged on the first fixing member (3).

3. The radial mobile fuel transient irradiation device applicable to a research reactor according to claim 1, characterized in that, A shielding cover plate (8) is connected to the in-core irradiation device (9), and the shielding cover plate (8) is configured such that when the in-core irradiation device (9) moves to the limit stroke, in the length direction of the in-core irradiation device (9), the shielding cover plate (8) can cover the opening.

4. The radial movable fuel transient irradiation device applicable to a research reactor according to claim 1, characterized in that, The in-core irradiation device (9) includes: A first housing (901), the first housing (901) being connected to the moving mechanism, the first housing (901) having a first cooling medium inlet (908); A second housing (902), the second housing (902) being inserted into the first housing (901), a medium flow channel (914) being formed between the inner wall of the second housing (902) and the first housing (901), the second housing (902) having an assembly interface located inside the first housing (901) and a first cooling medium outlet (909) located outside the first housing (901); Component installation box (904), the component installation box (904) is connected to the assembly interface through an intermediate joint (903), the component installation box (904) has an installation cavity (915) that communicates the medium flow channel (914) with the inside of the second housing (902), and the installation cavity (915) is used to install a fuel assembly (905); Heat exchanger (907), the heat exchanger (907) is disposed within the second housing (902), and the heat exchanger (907) has a second coolant inlet (910) and a second coolant outlet (911) respectively located outside the first housing (901).

5. The radial movable fuel transient irradiation device applicable to a research reactor according to claim 4, wherein The heat exchanger (907) includes a plurality of helical heat transfer tubes, and the plurality of helical heat transfer tubes are wound around each other to form a cylindrical heat exchange tube bundle.

6. The radial movable fuel transient irradiation device applicable to a research reactor according to claim 5, characterized in that, The helical heat transfer tube is configured as a double helical heat transfer tube (9071).

7. The radial movable fuel transient irradiation device applicable to a research reactor according to claim 4, characterized in that, A plurality of self-powered neutron detectors (913) are provided on the outer wall of the component installation box (904), wherein the self-powered neutron detectors (913) correspond to the center plane position of the active region of the fuel assembly (905).

8. The radial movable fuel transient irradiation device applicable to a research reactor according to claim 4, characterized in that, Thermocouples (912) are respectively provided at the front and rear ends of the component installation box (904) in the flow direction of the first coolant.

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