Nuclear reactor control rod falling experimental device and experimental method

Abstract

The invention discloses a nuclear reactor control rod falling experimental device and experimental method.The nuclear reactor control rod falling experimental device comprises a supporting frame, a control rod, a container pipe, a driving assembly, an observation window and a time measuring assembly, the container pipe is installed on the supporting frame and provided with a containing cavity with an opening, and the control rod is installed in the containing cavity; lead bismuth is stored in the accommodating cavity; the driving assembly is mounted above the support frame and is connected with the control rod; the observation window body is communicated with the opening of the accommodating cavity; the time measuring assembly is arranged on the container tube; the device is used for studying the rod falling time of the control rod and the flow state change of the liquid lead bismuth after the control rod is extruded during rod falling, the rod falling time can be accurately measured, the change of the liquid lead bismuth after the control rod is extruded can be visually studied, reference is provided for design optimization of the control rod in the liquid lead bismuth environment, and the method is suitable for popularization and application. And the experimental device is suitable for rod falling research of the control rod under various liquid metals, and is simple in structure, small and flexible.

Description

Technical Field

[0001] The present invention relates to the field of nuclear power technology, and in particular to a nuclear reactor control rod drop experimental device and an experimental method. Background Art

[0002] The reactor relies on control rods to achieve reactivity regulation. At the same time, in the event of a serious accident, the control rods rely on gravity to insert into the core to shut down the reactor. Control rods are extremely important to the safe operation of the reactor. Therefore, it is necessary to analyze whether they can fall into the core within the specified time under normal operation and accident conditions such as earthquakes.

[0003] In related technologies, the application of control rod drop experimental devices is mainly concentrated in water medium environment, while there are fewer studies and designs on control rod drop devices in liquid lead-bismuth medium environment. The water medium environment and the liquid lead-bismuth medium environment have different characteristics. For example, the operation of lead-bismuth reactor control rods needs to overcome environmental characteristics such as high density and high buoyancy. Generally, high-density counterweights need to be installed, or the buoyancy characteristics of liquid lead-bismuth high-density coolant are utilized to adopt a buoyancy drop method to rely on buoyancy to insert the control rod drop device from bottom to top in the water medium environment. This results in the control rod drop device in the water medium environment cannot be directly used in liquid lead-bismuth medium environment experimental research. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a nuclear reactor control rod drop experimental device.

[0005] The technical solution adopted by the present invention to solve its technical problem is:

[0006] A nuclear reactor control rod drop experimental device, comprising:

[0007] Support frames and control rods;

[0008] a container tube, the container tube being mounted on the support frame and defining a receiving cavity with an opening, wherein lead and bismuth are stored in the receiving cavity;

[0009] a drive assembly, the drive assembly being mounted above the support frame and connected to the control rod to suspend the control rod at the opening of the receiving cavity; the drive assembly drives the control rod to rise or fall within the receiving cavity;

[0010] an observation window, the observation window being connected to the opening of the receiving chamber for observing a state in which the lead and bismuth are squeezed by the control rod when it falls; and

[0011] A time measuring component is provided on the container tube to measure the falling time of the control rod.

[0012] Furthermore, in the nuclear reactor control rod drop experimental device, it is preferred that the nuclear reactor control rod drop experimental device also includes a heating component arranged on the container tube, so that the solid lead bismuth is heated and melted into liquid lead bismuth before the control rod drop experiment.

[0013] Furthermore, in the nuclear reactor control rod drop experimental device, it is preferred that the nuclear reactor control rod drop experimental device also includes a thermocouple arranged on the container tube to measure the temperature of the liquid lead bismuth.

[0014] Furthermore, in the nuclear reactor control rod drop experimental device, it is preferred that the nuclear reactor control rod drop experimental device also includes a high-speed camera, which corresponds to the observation window to capture the instantaneous changes in the squeezing of the liquid lead-bismuth when the control rod falls.

[0015] Furthermore, in the nuclear reactor control rod drop experimental device, the driving assembly preferably includes a driving member, a hook and a controller;

[0016] The driving member is connected to the control rod via a hook, and the controller is electrically connected to the driving member.

[0017] Furthermore, in the nuclear reactor control rod drop experimental device, preferably, a flow observation cavity is defined in the observation window, and the flow observation cavity is communicated with the receiving cavity.

[0018] Furthermore, in the nuclear reactor control rod drop experimental device, the observation window preferably includes a bottom plate, a surrounding plate, a top plate, a first through hole, and a second through hole;

[0019] The transparent enclosure is arranged at the edge of the bottom plate, and the top plate covers the enclosure to form the flow observation cavity; the first through hole is opened on the bottom plate and is connected to the opening of the receiving cavity; the second through hole is opened on the top plate.

[0020] Furthermore, in the nuclear reactor control rod drop experimental device, the control rod, the first through hole, the second through hole and the accommodating cavity are preferably coaxially arranged.

[0021] Furthermore, in the nuclear reactor control rod drop experimental device, the time measurement component preferably includes a first sensor, a second sensor, and a processor;

[0022] The first sensor is mounted at one end of the container tube close to the opening to measure the start time of the control rod's descent; the second sensor is mounted at one end of the container tube away from the opening to measure the end time of the control rod's descent; both the first sensor and the second sensor are electrically connected to the processor.

[0023] An experimental method for a nuclear reactor control rod drop experimental device comprises the following steps: S1, fixing the control rod on the drive assembly;

[0024] S2, the drive assembly drives the control rod to move up and down, and eliminates abnormal noise, jamming, and failure to smoothly drop the control rod during the process of dropping the control rod;

[0025] S3, performing free-fall rod drop, uniform-speed rod drop, accelerated rod drop, and decelerated rod drop experiments in an air environment, recording rod drop time data, and comparing the known time values ​​of free-fall rod drop, uniform-speed rod drop, accelerated rod drop, and decelerated rod drop with the time data to determine if there is a deviation. If there is a deviation, debugging the nuclear reactor control rod drop experiment device according to the deviation value. If there is no deviation, proceeding to S4;

[0026] S4, placing lead-bismuth in the receiving cavity of the container tube, and then driving the control rod by the drive assembly to perform free fall, uniform fall, accelerated fall, and decelerated fall in the receiving cavity of the container tube in a liquid lead-bismuth environment;

[0027] S5, the time measurement component obtains in real time the time of the free fall, uniform speed, accelerated and decelerated drop of the control rod, and the high-speed camera captures the metal flow state after the free fall, uniform speed, accelerated and decelerated drop of the control rod squeezes the liquid lead and bismuth.

[0028] The implementation of the present invention has the following beneficial effects: it is used to study the control rod drop time and the flow state changes of liquid lead-bismuth after being squeezed by the control rod during the drop, can accurately measure the rod drop time, and visualize the changes of liquid lead-bismuth after the control rod is squeezed, providing a reference for the design optimization of control rods in liquid lead-bismuth environments. It is also applicable to the control rod drop research under various liquid metals. The experimental device has a simple structure, is compact and flexible, and is easy to operate. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0030] Figure 1 This is a schematic structural diagram from a first perspective of a nuclear reactor control rod drop experimental device in some embodiments of the present invention;

[0031] Figure 2 yes Figure 1 The longitudinal cross-sectional structural diagram is shown. DETAILED DESCRIPTION

[0032] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, the specific embodiments of the present invention are now described in detail with reference to the accompanying drawings. In the following description, it should be understood that the directions or positional relationships indicated by "front", "back", "up", "down", "left", "right", "longitudinal", "horizontal", "vertical", "horizontal", "top", "bottom", "inside", "outside", "head", "tail", etc. are based on the directions or positional relationships shown in the accompanying drawings and are constructed and operated in specific directions. They are only for the convenience of describing the technical solution and do not indicate that the devices or components referred to must have specific directions. Therefore, they should not be understood as limiting the present invention.

[0033] It should also be noted that, unless otherwise clearly specified and limited, terms such as "installed", "connected", "connected", "fixed", and "set" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. When an element is referred to as being "on" or "under" another element, the element can be "directly" or "indirectly" located on the other element, or there may be one or more intervening elements. The terms "first", "second", "third", etc. are only for the convenience of describing the present technical solution, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second", "third", etc. may explicitly or implicitly include one or more of such features. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0034] In the following description, specific details such as particular system structures and techniques are provided for purposes of illustration, not limitation, to facilitate a thorough understanding of the embodiments of the present invention. However, it will be apparent to those skilled in the art that the present invention may be practiced in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present invention with unnecessary detail.

[0035] The technical solution adopted by the present invention to solve its technical problem is:

[0036] like Figure 1 and Figure 2As shown, some embodiments of the present invention disclose a nuclear reactor control rod drop experimental device. In some embodiments, the nuclear reactor control rod drop experimental device may include: a support frame 10, a control rod 20, a container tube 30, a drive assembly 40, and a time measurement assembly 60. The container tube 30 is vertically mounted on the support frame 10 and defines a receiving cavity 310 with an opening. The drive assembly 40 is mounted on the top of the support frame 10 and connected to the top of the control rod 20 to suspend the control rod 20 at the opening of the receiving cavity 310. The time measurement assembly 60 is mounted on the container tube 30. The drive assembly 40 drives the control rod 20 to move up and down within the receiving cavity 310 at a constant speed, with acceleration and deceleration. The time measurement assembly 60 measures the time it takes for the control rod 20 to fall.

[0037] Continue to refer Figure 2 In some embodiments, the nuclear reactor control rod drop experiment apparatus further includes an observation window 50, a heating assembly 70, and a high-speed camera 80. The aforementioned receiving chamber 310 contains lead-bismuth. The transparent observation window 50 is mounted on the support frame 10 and communicates with the receiving chamber 310 through the aforementioned opening. The heating assembly 70 is mounted on the container tube 30. The lead-bismuth is stored in solid form. During the control rod 20 drop experiment, the lead-bismuth is heated and melted into liquid form by the heating assembly 70. The high-speed camera 80 corresponds to the observation window 50 and captures the squeezing of the liquid lead-bismuth by the control rod 20 during its drop.

[0038] In some embodiments, the support frame 10 may include a base 11, support rods 12, and a top base 13. Four support rods 12 are provided, and the four support rods 12 are installed between the base 11 and the top base 13 and located at the four corners of the base 11 and the top base 13 to form a stable frame structure.

[0039] Before the experiment, the base 11 is fixed on the ground or platform to prevent the support frame 10 from tilting during the experiment. It can be understood that the base 11 can be fixed on the ground by pins, screws, bonding, clamping, etc.

[0040] In some embodiments, the control rod 20 has an annular groove at its top end for connection to the drive assembly 40. The control rod 20 is made of metal and is understood to be a simulation of a control rod in a liquid lead-bismuth reactor.

[0041] For reference Figure 1In some embodiments, the container tube 30 is mounted on the upper surface of the base 11 of the support frame 10. It is understood that the container tube 30 is a tube with an opening at the top. Of course, the container tube 30 can also have a square structure with an opening, or an irregular shape. Similarly, the receiving cavity 310 can have a tubular structure, a square structure, or other shapes. It should be noted that the inner diameter of the receiving cavity 310 is greater than or equal to the outer diameter of the control rod 20, so that the control rod 20 can move freely up and down within the receiving cavity 310.

[0042] In some embodiments, the drive assembly 40 may include a drive member 41 mounted on the top base 13 and a hook connected to the drive member 41. The hook hooks onto the annular groove of the control rod 20. Furthermore, the drive member 41 is electrically connected to a controller to control the opening and closing of the drive member 41 and the output frequency (the output frequency is adjusted to control the constant speed, acceleration, and deceleration of the vertical movement of the control rod 20 by the hook). It is understood that the drive member 41 may be a motor, a cylinder, a linear module, etc.

[0043] In some embodiments, the output end of the drive member 41 (e.g., a motor) is mounted with a drive rod. A lifting rope is wound around the drive rod, which is connected to a hook. The drive member 41 drives the drive rod to wind or lower the lifting rope, causing the hook to raise or lower the control rod 20.

[0044] In other embodiments, the output end of the drive member 41 (e.g., a motor) may be mounted with a lead screw. A nut is mounted on the lead screw (the nut only moves and does not rotate with the lead screw), and a hook is mounted on the nut. The drive member 41 rotates the lead screw, and the nut on the lead screw drives the hook up or down, thereby causing the control rod 20 to move up and down.

[0045] In other embodiments, the output end of the drive member 41 (a cylinder) can be directly connected to the hook. The drive member 41 directly drives the hook to move the control rod 20 up and down. Of course, the drive assembly 40 can also be configured as other ascending and descending devices known in the art.

[0046] Reference again Figure 2In some embodiments, the observation window 50 may include a bottom plate 51, a surrounding plate 52, a top plate 53, a first through-hole 54, and a second through-hole 55. The bottom plate 51 is mounted on the support rod 12 of the support frame 10, the surrounding plate 52 is mounted between the bottom plate 51 and the top plate 53, and the top plate 53 is mounted on the support rod 12 of the support frame 10. The bottom plate 51, the surrounding plate 52, and the top plate 53 form a hexahedron structure, within which a flow observation chamber 510 is formed. When liquid lead-bismuth is squeezed, it splashes and flows freely within the flow observation chamber 510, facilitating observation of the squeeze of the liquid lead-bismuth by the control rod 20. The first through-hole 54 is provided in the bottom plate 51 and communicates with the opening of the receiving chamber 310, allowing the squeezed liquid lead-bismuth within the container tube 30 to enter the flow observation chamber 510. The second through-hole 55 is provided in the top plate 53, allowing the control rod 20 to enter the receiving chamber 310 of the container tube 30 through the second through-hole 55 when it falls.

[0047] In some embodiments, the time measurement assembly 60 may include a first sensor 61, a second sensor 62, and a processor 63. The first sensor 61 is mounted at the end of the container tube 30 near the opening to measure the start time of the control rod 20's descent; the second sensor 62 is mounted at the end of the container tube 30 away from the opening to measure the end time of the control rod 20's descent. Both the first sensor 61 and the second sensor 62 are electrically connected to the processor 63. It will be appreciated that the first and second sensors 61 and 62 are positioned along the descent path of the control rod 20. When the control rod 20 descents, the first and second sensors 61 and 62 are triggered and converted into electrical signals. The processor 63 receives the electrical signals from the first and second sensors 61 and 62 to measure the time it takes for the control rod 20 to fall.

[0048] In some embodiments, the first sensor 61 and the second sensor 62 are mounted on the container tube 30 using nuts, bolts, clamping, bonding, or other methods. Of course, corresponding mounting structures can also be provided on the container tube 30. For example, the container tube 30 can be provided with threads, and the first sensor 61 and the second sensor 62 can be screwed into the threads using bolts.

[0049] In some embodiments, the heating assembly 70 is installed within the receiving cavity 310 of the container tube 30. The lead-bismuth is stored in a solid state. Therefore, before the experiment, the heating assembly 70 needs to heat and melt the solid lead-bismuth into liquid form. Furthermore, a thermocouple 71 is provided on the container tube 30 to measure the temperature of the lead-bismuth during heating.

[0050] In some embodiments, the heating assembly 70 may use coil heating, infrared heating, electromagnetic heating, etc. The thermocouple 71 may also use a temperature sensor, an infrared detector, etc.

[0051] In some embodiments, the high-speed camera 80 corresponds to the observation window 50 to capture the instantaneous changes in the squeezing of the liquid lead-bismuth by the control rod 20 when it falls.

[0052] An experimental method for a nuclear reactor control rod drop experimental device includes the following steps: S1, fixing the control rod 20 on the drive assembly 40.

[0053] Assemble and secure the support frame 10, container tube 30, drive assembly 40, observation window 50, time measuring device 60, and heating assembly 70. Then, secure the support frame 10 to the ground. Connect the control rod 20 to the hook of the drive assembly 40 so that the control rod 20 is suspended at the opening of the container tube 30.

[0054] S2, the driving assembly 40 drives the control rod 20 to move up and down in a small range to eliminate abnormal noise, jamming, and smooth landing of the control rod 20 during the process of dropping the control rod 20.

[0055] In some embodiments, it is necessary to eliminate the phenomenon that the control rod 20 gets stuck at the opening of the container tube 30, fails to smoothly fall into the opening of the container tube 30, or bumps into the opening of the container tube 30. In addition, it is necessary to measure whether the control rod 20 can trigger the first sensor 61 and the second sensor 62.

[0056] S3, respectively carry out free-fall rod drop, uniform-speed rod drop, accelerated rod drop and decelerated rod drop experiments in an air environment, record rod drop time data, and compare the known time values ​​of free-fall rod drop, uniform-speed rod drop, accelerated rod drop and decelerated rod drop with the time data to see if there is any deviation. If there is a deviation, debug the nuclear reactor control rod drop experimental device according to the deviation value. If there is no deviation, proceed to S4.

[0057] The time measurement component 60 records the time data of the control rod 20 driven by the drive component 40 to perform free fall, uniform speed drop, accelerated drop and decelerated drop in the container tube 30 in an air environment, and compares the time data based on the known free fall, uniform speed drop, accelerated drop and decelerated drop time values ​​to see if there are any deviations. Based on the deviation time values, it is checked whether the control rod 20 is stuck during the driving process. At the same time, it is checked whether the time measurement component 60 is working normally, and the faults of the nuclear reactor control rod drop experimental device are checked one by one, and the faulty components (parts) of the nuclear reactor control rod drop experimental device are replaced or repaired.

[0058] In some embodiments, the times of free fall, uniform speed drop, accelerated drop and decelerated drop of the control rod 20 in an air environment are known. After the nuclear reactor control rod drop experimental device is assembled, the times of free fall, uniform speed drop, accelerated drop and decelerated drop are tested and recorded. The recorded times are compared with the known values ​​(existing experimental drop times) to see if there are any deviations. If there are any deviations, it is necessary to check whether the control rod 20 is stuck during the driving process based on the deviation time value, and at the same time check whether the time measurement component 60 is working normally. The faults of the nuclear reactor control rod drop experimental device are checked one by one, and the faulty components (components) of the nuclear reactor control rod drop experimental device are replaced or repaired. If there are no deviations, proceed to the next step.

[0059] For example, if the driving assembly 40 cannot drive the control rod 20 to fall vertically, a jamming phenomenon will occur; the movement mode of the driving assembly 40 and the connection stability of the control rod 20 need to be adjusted.

[0060] S4, lead-bismuth is placed in the receiving cavity 310 of the container tube 30, and then the drive assembly 40 drives the control rod 20 to perform free fall, uniform fall, accelerated fall, and decelerated fall in the receiving cavity 310 of the container tube 30 in the liquid lead-bismuth environment.

[0061] Solid lead bismuth is placed in the receiving cavity 310 of the container tube 30, and the heating component 70 is started to heat the solid lead bismuth and melt it into liquid lead bismuth. The temperature of the liquid lead bismuth is fed back in real time through the thermocouple 71, and the heating component 70 is controlled to stop heating when the melting point temperature is reached.

[0062] S5, the time measurement component 60 obtains the time of the free fall, uniform speed, accelerated and decelerated drop of the control rod 20 in real time, and the high-speed camera 80 captures the squeezing changes of the liquid lead-bismuth caused by the free fall, uniform speed, accelerated and decelerated drop of the control rod 20.

[0063] A high-speed camera 80 is used to capture the sputtering state of the control rod 20 squeezing the liquid lead-bismuth at different speeds, namely, free fall, uniform fall, accelerated fall, and decelerated fall.

[0064] S6. After the experiment is completed, the control rod 20 is lifted above the container tube 30, the time measurement component 60 and the drive component 40 are closed, and after the temperature of the liquid lead-bismuth drops to the specified temperature, the liquid lead-bismuth inside the observation window 50 is treated with chemical reagents.

[0065] It can be understood that the above embodiments only express the preferred implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the patent scope of the present invention. It should be pointed out that for ordinary technicians in this field, without departing from the concept of the present invention, the above technical features can be freely combined, and several deformations and improvements can be made, all of which fall within the scope of protection of the present invention. Therefore, all equivalent changes and modifications made to the scope of the claims of the present invention should fall within the scope of coverage of the claims of the present invention.

Claims

1. A nuclear reactor control rod drop test device, comprising a control rod (20); characterized in that: include: Support frame (10); A container tube (30), the container tube (30) being mounted on the support frame (10), and having a receiving cavity (310) with an opening, wherein lead and bismuth are stored in the receiving cavity (310); a drive assembly (40), the drive assembly (40) being installed above the support frame (10) and connected to the control rod (20) so as to suspend the control rod (20) at the opening of the receiving cavity (310); the drive assembly (40) drives the control rod (20) to rise or fall in the receiving cavity (310); an observation window (50), the observation window (50) being connected to the opening of the receiving chamber (310) for observing the squeezing state of the lead-bismuth by the control rod (20) when it falls; as well as A time measuring component (60) is provided on the container tube (30) to measure the falling time of the control rod (20).

2. The nuclear reactor control rod drop experimental device according to claim 1, characterized in that: The nuclear reactor control rod drop test device further comprises a heating assembly (70) arranged on the container tube (30) so as to heat and melt the solid lead-bismuth into liquid lead-bismuth before the control rod (20) drops.

3. The nuclear reactor control rod drop experimental device according to claim 2, characterized in that: The nuclear reactor control rod drop experimental device further comprises a thermocouple (71) arranged on the container tube (30) to measure the temperature of the liquid lead-bismuth.

4. The nuclear reactor control rod drop experimental device according to claim 3, characterized in that: The nuclear reactor control rod drop experimental device further comprises a high-speed camera (80), which corresponds to the observation window (50) to capture instantaneous changes in the squeezing of the liquid lead-bismuth by the control rod (20) when it falls.

5. The nuclear reactor control rod drop experimental device according to claim 1, characterized in that: The driving assembly (40) includes a driving member (41), a hook and a controller; The driving member (41) is connected to the control rod (20) via a hook, and the controller is electrically connected to the driving member (41).

6. The nuclear reactor control rod drop experimental device according to claim 4, characterized in that: A flow observation cavity (510) is defined in the observation window (50), and the flow observation cavity (510) is communicated with the receiving cavity (310).

7. The nuclear reactor control rod drop experimental device according to claim 6, characterized in that: The observation window (50) comprises a bottom plate (51), a surrounding plate (52), a top plate (53), a first through hole (54) and a second through hole (55); The transparent enclosure (52) is arranged at the edge of the bottom plate (51), and the top plate (53) covers the enclosure (52) to form the flow observation cavity (510); the first through hole (54) is opened on the bottom plate (51) and is connected to the opening of the receiving cavity (310); the second through hole (55) is opened on the top plate (53).

8. The nuclear reactor control rod drop experimental device according to claim 7, characterized in that: The control rod (20), the first through hole (54), the second through hole (55), and the receiving cavity (310) are coaxially arranged.

9. The nuclear reactor control rod drop experimental device according to claim 1, characterized in that: The time measurement component (60) includes a first sensor (61), a second sensor (62) and a processor (63); The first sensor (61) is installed at one end of the container tube (30) close to the opening to measure the start time of the control rod (20) falling; the second sensor (62) is installed at one end of the container tube (30) away from the opening to measure the end time of the control rod (20) falling; the first sensor (61) and the second sensor (62) are both electrically connected to the processor (63).

10. An experimental method for a nuclear reactor control rod drop experimental device, according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1, fixing the control rod (20) to the drive assembly (40); S2, the driving assembly (40) drives the control rod (20) to move up and down, and eliminates the situation in which the control rod (20) makes abnormal noise, freezes, or fails to fall smoothly during the process of falling; S3, performing free-fall rod drop, uniform-speed rod drop, accelerated rod drop, and decelerated rod drop experiments in an air environment, recording rod drop time data, and comparing the known time values ​​of free-fall rod drop, uniform-speed rod drop, accelerated rod drop, and decelerated rod drop with the time data to determine if there is a deviation. If there is a deviation, debugging the nuclear reactor control rod drop experiment device according to the deviation value. If there is no deviation, proceeding to S4; S4, placing lead-bismuth in the receiving cavity (310) of the container tube (30), and then driving the control rod (20) by the driving assembly (40) to perform free fall, uniform fall, accelerated fall, and decelerated fall in the receiving cavity (310) of the container tube (30) in a liquid lead-bismuth environment; S5, the time measurement component (60) obtains in real time the time of the free fall, uniform speed, accelerated and decelerated drop of the control rod (20), and the high-speed camera (80) captures the metal flow state after the free fall, uniform speed, accelerated and decelerated drop of the control rod (20) squeezes the liquid lead and bismuth.

Images