Plate-type fuel assembly vibration test device and method

Abstract

The invention discloses a plate-type fuel assembly vibration test device and method, and belongs to the field of nuclear power. The plate-type fuel assembly vibration test device comprises a base, a clamping grid plate and a vibration excitation device, wherein the clamping grid plate and the vibration excitation device are connected to the base; wherein the clamping grid plate comprises a first grid plate and a second grid plate which can move relatively, and the first grid plate and the second grid plate provide clamping slots with different sizes at different positions for mounting the plate type fuel assembly; the plate-type fuel assembly abuts against the vibration excitation device in the installation state so that the vibration excitation device can provide vibration excitation for the plate-type fuel assembly. The device can adjust the constraint condition of the installation position of the plate-type fuel assembly, provides different vibration test boundary conditions, improves the test efficiency, and reduces the test cost.

Description

Technical Field

[0001] The invention belongs to the field of nuclear power, and in particular relates to a vibration test device and method for a plate-type fuel assembly. Background Art

[0002] Plate fuel assemblies are widely used in experimental reactors and other reactors. Due to the plate-like structural characteristics of fuel assemblies, plate fuel assemblies are significantly affected by flow-induced vibration. The basic dynamic characteristics of plate fuel assemblies, including natural frequency, vibration mode, damping ratio, etc., have an important influence on the mechanical analysis of fuel assemblies and related experimental design. Therefore, it is of great value to obtain the vibration performance of plate fuel assemblies by conducting vibration tests.

[0003] "Experimental Study on Fluid-Solid Coupling of a Single Flexible Plate in a Rectangular Channel" (Zhao Yujing, [D]. North China Electric Power University, 2010. DOI: 10.7666 / d.y1796924.) discloses a vibration test device, which simplifies the parallel plate fuel assembly into a flexible plate structure with four corners fixed in a rigid rectangular channel, and simulates the vibration behavior of the plate fuel in the flow field. However, this test method only simulates the vibration behavior of the fuel plate itself, while the boundary conditions of the vibration state of the plate fuel assembly under actual working conditions are provided by the fixed end constraints of the plate fuel assembly. The four-corner fixed method adopted by the technical solution disclosed in the document cannot accurately simulate the influence of different constraints on the vibration behavior of the plate fuel assembly, and cannot meet the actual test requirements.

[0004] Therefore, providing a plate-type fuel assembly vibration test device capable of simulating different constraint states of the fixed end has positive significance for the study of the vibration behavior of the plate-type fuel assembly. Summary of the invention

[0005] The purpose of the present invention is to provide a plate-type fuel assembly vibration test device to improve the efficiency and accuracy of the plate-type fuel assembly vibration test. The present invention also provides a plate-type fuel assembly vibration test method.

[0006] According to an embodiment of one aspect of the present invention, a plate-type fuel assembly vibration test device is provided, the device comprising:

[0007] Base, clamping grid plate and excitation device; wherein,

[0008] The clamping grid plate and the excitation device are connected to the base;

[0009] The clamping grid plate comprises a first grid plate and a second grid plate, the first grid plate and the second grid plate are relatively movable, the first grid plate and the second grid plate provide a card slot to allow the fixed end of the plate-type fuel assembly to be inserted into the card slot, and the size of the card slot is adjusted by the spacing between the first grid plate and the second grid plate;

[0010] When the fixed end of the plate-type fuel assembly is inserted into the card-joining slot, the vibration excitation device abuts against the plate-type fuel assembly to provide vibration excitation to the plate-type fuel assembly.

[0011] The test device can adjust the matching relationship of the fixed end of the plate-type fuel assembly according to the test requirements to change the boundary conditions of the vibration state of the plate-type fuel assembly, effectively improve the accuracy of the test simulation, reduce the manufacturing cycle of the tooling fixture, and reduce the test cost.

[0012] Furthermore, in some embodiments, a guide rail is provided on the base, and the first grid plate and the second grid plate are slidably connected to the guide rail.

[0013] Furthermore, in some embodiments, a locking device is provided between the base and the clamping grid plate, and the locking device has a locking state, in which the locking device provides a limiting stop for the clamping grid plate.

[0014] Further, in some embodiments, the clamping grid plate includes a gap adjustment mechanism, and the gap adjustment mechanism adjusts the gap between the first grid plate and the second grid plate.

[0015] Furthermore, in some embodiments, the gap adjustment mechanism is configured as a gap adjustment bolt.

[0016] Furthermore, in some embodiments, the vibration excitation device includes a vibration exciter and a vibration excitation rod, the vibration exciter provides vibration excitation, and the vibration excitation rod transmits the vibration excitation to the plate-type fuel assembly.

[0017] Furthermore, in some embodiments, the base includes a column, and the excitation device is fixedly mounted on the column.

[0018] Furthermore, in some embodiments, a water environment test box is also included, wherein the water environment test box holds the grid plate and at least a part of the base and at least a part of the excitation device, and the water environment test box provides a liquid environment for immersing the plate-type fuel assembly.

[0019] Furthermore, in some embodiments, a sealing component is provided at the boundary below the maximum capacity water filling line of the water environment test box.

[0020] According to another embodiment of the present invention, a plate-type fuel assembly vibration test method is provided, the method using the plate-type fuel assembly vibration test device provided in any of the above embodiments, and comprising the following steps:

[0021] Step a): providing test parameters for the matching relationship between the card slot and the fixed end of the plate-type fuel assembly;

[0022] Step b): adjusting the clamping grid plate according to the test parameters and installing the plate-type fuel assembly; connecting the excitation device to the plate-type fuel assembly;

[0023] Step c): providing an air environment or a water environment, and starting the vibration excitation device to provide loading to the plate-type fuel assembly.

[0024] The beneficial effects that can be achieved by the above embodiments are: restoring the real constraint state of the plate-type fuel assembly in the grid plate, and obtaining the modal characteristics of the plate-type fuel assembly under different boundary conditions through a set of test systems, without the need to manufacture multiple sets of grid plates of different sizes, thereby reducing test costs and improving test efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of the structure of a plate-type fuel assembly test system in one embodiment;

[0026] Figure 2 A partial top view of a grid plate clamping structure of a plate-type fuel assembly system in one embodiment.

[0027] Meaning of the reference symbols:

[0028] 1- base;

[0029] 2- Pillar;

[0030] 3- Vibrator;

[0031] 4- Sealing port;

[0032] 5- Stirring rod;

[0033] 6- Plate fuel assembly;

[0034] 7- Water environment box;

[0035] 8- first grid plate;

[0036] 9- second grid plate;

[0037] 10- Sealing gasket;

[0038] 11-locking bolt;

[0039] 12-Guide rail;

[0040] 13-card slot;

[0041] 14-Adjusting bolt.

[0042] The purpose of the above drawings is to explain the present invention in detail so that those skilled in the art can understand the technical concept of the present invention, but it is not intended to limit the present invention. For the sake of simplicity, the above drawings only schematically illustrate the structures related to the technical features of the present invention, and do not strictly follow the actual proportions to draw the complete structure and all details. DETAILED DESCRIPTION

[0043] The present invention is further described in detail below through specific embodiments.

[0044] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present invention. The phrase appearing in various locations in the specification does not necessarily refer to the same embodiment, nor is it limited to mutually exclusive independent or alternative embodiments. Those skilled in the art should be able to understand that the embodiments herein may be combined with other embodiments without causing structural conflicts.

[0045] In the description of this article, unless otherwise clearly specified and limited, the technical terms "installed", "connected", "connected" and the like should be understood in a broad sense, for example, it can be a movable connection, a fixed connection or an integral connection. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of this application can be understood according to specific circumstances.

[0046] In the description of this document, terms indicating orientation or positional relationships, such as "up", "down", "left", "right", "horizontal", "vertical", "height", "length", and "width", are intended to accurately describe the embodiments and simplify the description, but are not intended to limit the parts or structures involved to have a specific orientation, be installed or operate in a specific orientation, and should not be construed as a limitation on the embodiments in this document.

[0047] In the description of this article, the terms "first", "second" and the like are only used to distinguish different objects, and cannot be understood as indicating relative importance or limiting the quantity, specific order or primary and secondary relationship of the described technical features. In the description of this article, the meaning of "plurality" is at least two.

[0048] Plate fuel assemblies are widely used in research reactors and other reactors. In various research projects, the performance of plate fuel assemblies has an important impact on test design and data analysis. As the basic dynamic characteristics of plate fuel assemblies, modal characteristics include natural frequency, vibration mode and damping ratio, which can not only be used as input parameters and verification basis for the mechanical analysis model of plate fuel assemblies, but also provide reference for bench design, input load selection, etc. in subsequent seismic, collision and other dynamic tests.

[0049] The modal characteristics of plate fuel assemblies can be measured through vibration tests. Different types of loads such as white noise, sine sweep and fixed frequency are applied to the plate fuel assemblies using loading devices such as vibrators and vibration tables. Acceleration or displacement sensors are arranged to measure the time response of the acceleration or displacement generated by the assembly, and the response curves of displacement or acceleration with frequency are calculated and plotted to obtain the modal characteristics of the plate fuel assemblies.

[0050] In actual reactors, the bottom of the plate fuel assembly is inserted into the grid plate for positioning. To ensure the insertability of the assembly, there is a certain gap between the grid plate and the assembly. Considering the manufacturing and installation errors, the gap may be higher or lower than the nominal value. The vibration test of the plate fuel assembly needs to restore the actual constraint state of the assembly in the grid plate, and conduct tests under different working conditions of the gap between the assembly and the grid plate. However, if the method of separately manufacturing and processing grid plates of different sizes is adopted, it will take a lot of time and economic costs, which is not conducive to the smooth progress of the vibration test of the plate fuel assembly.

[0051] In order to solve the above problems, an embodiment of one aspect of the present invention provides a plate fuel assembly vibration test device, which can apply adjustable constraints to the bottom fixed end of the plate fuel assembly through a grid plate, so as to obtain the modal characteristics of the plate fuel assembly under different constraint states through the same set of test equipment, thereby reducing test costs and improving test efficiency.

[0052] The structure of the device is as follows Figure 1 As shown, it includes a base 1, a clamping grid plate and an exciting device.

[0053] The base is fixed on the ground to provide stable support for the entire test device. Components such as the clamping grid plate and the excitation device are connected to the base 1.

[0054] The clamping grid plate includes a first grid plate 8 and a second grid plate 9. The first grid plate 8 and the second grid plate 9 can move relative to each other so that the gap between them changes. Figure 2 A card slot 13 is formed between the first grid plate 8 and the second grid plate 9, and the bottom fixed end of the plate fuel assembly 6 can be inserted into the card slot 13 to be fixed. By adjusting the gap between the first grid plate 8 and the second grid plate 9, the matching relationship between the card slot 13 and the plate fuel assembly 6 can be changed, thereby providing different constraint states for the plate fuel assembly 6.

[0055] In a preferred embodiment, a guide rail 12 is provided on the base 1, and the first grid plate 8 and the second grid plate 9 are mounted on the guide rail 12 and can slide along the guide rail 12. Locking bolts 11 are respectively provided between the first grid plate 8 and the second grid plate 9 and the guide rail 12, and the first grid plate 8 and the second grid plate 9 can be locked and stopped by tightening the locking bolts 11. In other embodiments, the locking bolts 11 can also be replaced by locking mechanisms such as locking pins or locking buckles.

[0056] In a preferred embodiment, an adjusting bolt 14 is provided between the first grid plate 8 and the second grid plate 9, and corresponding bolt holes are provided in the first grid plate 8 and the second grid plate 9. The adjusting bolt 14 is provided in the bolt hole, and the gap between the first grid plate 8 and the second grid plate 9 can be further adjusted by rotating the adjusting bolt 14. For example, the gap between the first grid plate 8 and the second grid plate 9 can be increased by pushing the adjusting bolt 14 to increase the width of the card slot 13; the adjusting bolt 14 can also be further tightened to compress the first grid plate 8 and the second grid plate 9 by the axial tension of the adjusting bolt 14 to reduce the gap, thereby achieving the effect of further reducing the width of the card slot 13.

[0057] In a preferred embodiment, the base 1 includes a protruding column 2, and the excitation device is fixedly connected to the column 2. When the bottom fixed end of the plate fuel assembly 6 is inserted and fixed in the card slot 13, the excitation device can abut the upper part of the plate fuel assembly 6 to excite the vibration of the plate fuel assembly 6.

[0058] Specifically, the vibration excitation device includes a vibration exciter 3 and a vibration excitation rod 5 . The vibration exciter 3 is used to generate vibration excitation, and the vibration excitation rod 5 is used to transmit the vibration to the plate-type fuel assembly 6 .

[0059] In a preferred embodiment, the test device further comprises a water environment box 7, and the clamping grid plate, the guide rail 12, the plate fuel assembly 6 and part of the excitation rod 5 are enclosed in the water environment box 7. When the water environment box 7 is filled with water, the plate fuel assembly 6 can be immersed below the liquid surface to simulate the vibration behavior in the water environment.

[0060] Specifically, a sealing component is provided at the boundary of the water environment box 7 to prevent leakage during the test. A sealing gasket 10 is provided between the water environment box 7 and the base 1 to prevent leakage at the bottom of the water environment box 7; a sealing port 4 is provided on the side wall of the water environment box to allow the excitation rod 5 to pass through the sealing port 4 to maintain a sealed state and avoid leakage from the side during the test. Furthermore, the sealing component is made of elastic materials such as rubber to prevent fatigue damage to the seal during the vibration test, which affects the sealing performance of the test device.

[0061] In other embodiments, when the test device is not equipped with the water environment box 7, the entire device may be waterproofed and then immersed in a test water pool to perform a water environment vibration simulation test.

[0062] In a preferred embodiment, the Figure 1 , Figure 2 The process of performing vibration test on the plate-type fuel assembly vibration test device shown is as follows:

[0063] First, the test parameters to be tested are provided, including the matching relationship parameters of the bottom fixed ends of multiple plate-type fuel assemblies, which will affect the boundary conditions of the vibration test.

[0064] Next, the first grid plate 8 and the second grid plate 9 are respectively installed on the guide rails 12 , the locking bolts 11 are temporarily tightened for positioning, and the fixed end at the bottom of the plate-type fuel assembly 6 is inserted into the card slot 13 .

[0065] Install the vibrator 3 on the column 2, pass the vibrator rod 5 through the sealing port 4 of the water environment box 7 and abut against the plate fuel assembly 6, ensuring that there is no gap between the vibrator rod 5 and the plate fuel assembly 6. Adjust the position of the clamping grid plate so that the plate fuel assembly 6 can maintain abutment with the vibrator rod 5 in a normal vertical state, and then tighten the locking bolt 11 on the second grid plate 9 close to the column 2 to position the second grid plate 9. With the second grid plate 9 as the positioning reference, adjust the position of the first grid plate 8, and adjust the gap between the two grid plates to the preset matching relationship parameters by adjusting the bolt 14.

[0066] After the device is assembled, the excitation device is started to provide vibration loading to the plate fuel assembly 6 and conduct a vibration test. Specifically, when conducting an air vibration environment test, the water environment box 7 is kept dry; when conducting a water environment vibration test, water is filled in the water environment box 7 to a given depth to immerse the plate fuel assembly 6, and loading is performed after checking that the water environment box 7 is leak-free. During the test, the vibration behavior of the plate fuel assembly 6 can be measured by a displacement or acceleration sensor, and the modal characteristics of the plate fuel assembly 6 such as frequency, vibration mode and damping ratio under the corresponding boundary conditions can be calculated.

[0067] After completing the test of a set of matching relationship parameters, adjust the adjusting bolt 14 to change the matching relationship between the card slot 13 and the bottom fixed end of the plate-type fuel assembly 6 to change the fixed end constraint state, and repeat the test until all parameter tests are completed.

[0068] Through this device, the constraint state of the fixed end of the plate fuel assembly can be adjusted quickly and easily, and the vibration behavior under different boundary conditions can be tested, which avoids repeated manufacturing and assembly of the fixing fixture, reduces the test cost, and improves the test efficiency. Through a single test device, the vibration behavior of the plate fuel assembly covering different boundary conditions can be studied, and the accuracy of the simulation test can be improved.

[0069] The purpose of the above embodiments is to further explain the present invention in detail in conjunction with the accompanying drawings so that those skilled in the art can understand the technical concept of the present invention. Within the scope of the present invention, the optimization or equivalent replacement of the part structure or method steps involved, and the combination of implementation methods in different embodiments without conflict of structure and principle, all fall within the protection scope of the present invention.

Claims

1. A plate-type fuel assembly vibration test device, characterized in that: include: Base, clamping grid plate and excitation device; wherein, The clamping grid plate and the excitation device are connected to the base; The clamping grid plate comprises a first grid plate and a second grid plate, the first grid plate and the second grid plate are relatively movable, the first grid plate and the second grid plate provide a card slot to allow the fixed end of the plate-type fuel assembly to be inserted into the card slot, and the size of the card slot is adjusted by the spacing between the first grid plate and the second grid plate; When the fixed end of the plate-type fuel assembly is inserted into the card-joining slot, the vibration excitation device abuts against the plate-type fuel assembly to provide vibration excitation to the plate-type fuel assembly.

2. The plate-type fuel assembly vibration test device according to claim 1, characterized in that: A guide rail is arranged on the base, and the first grid plate and the second grid plate are slidably connected to the guide rail.

3. The plate-type fuel assembly vibration test device according to claim 1 or 2, characterized in that: A locking device is provided between the base and the clamping grid plate, and the locking device has a locking state. In the locking state, the locking device provides a limit stop for the clamping grid plate.

4. The plate-type fuel assembly vibration test device according to claim 1 or 2, characterized in that: The clamping grid plate includes a gap adjustment mechanism, which adjusts the gap between the first grid plate and the second grid plate.

5. The plate-type fuel assembly vibration test device according to claim 4, characterized in that: The gap adjustment mechanism is configured as a gap adjustment bolt.

6. The plate-type fuel assembly vibration test device according to claim 1 or 2, characterized in that: The vibration excitation device includes a vibration exciter and a vibration excitation rod. The vibration exciter provides vibration excitation, and the vibration excitation rod transmits the vibration excitation to the plate-type fuel assembly.

7. The plate-type fuel assembly vibration test device according to claim 1 or 2, characterized in that: The base comprises a column, and the excitation device is fixedly mounted on the column.

8. The plate-type fuel assembly vibration test device according to claim 1 or 2, characterized in that: It also includes a water environment test box, which holds the grid plate and at least a part of the base and at least a part of the excitation device, and provides a liquid environment for immersing the plate-type fuel assembly.

9. The plate-type fuel assembly vibration test device according to claim 8, characterized in that: A sealing component is arranged at the boundary below the maximum capacity water filling line of the water environment test box.

10. A vibration test method for a plate-type fuel assembly, characterized in that: A plate-type fuel assembly vibration test device as claimed in any one of claims 1 to 9 is used, and comprises the following steps: Step a): providing test parameters for the matching relationship between the card slot and the fixed end of the plate-type fuel assembly; Step b): adjusting the clamping grid plate according to the test parameters and installing the plate-type fuel assembly; connecting the excitation device to the plate-type fuel assembly; Step c): providing an air environment or a water environment, and starting the vibration excitation device to provide loading to the plate-type fuel assembly.

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