A low-vibration exciter fixing device and its usage method for anechoic water tank testing

Abstract

This invention relates to a low-vibration exciter fixing device and its usage method for anechoic tank testing, belonging to the field of ship vibration and noise testing technology. This invention solves the problems of traditional anechoic tank vibration and noise testing, which cannot flexibly excite underwater structures and suffer from significant vibration transmission effects from the exciter itself. The main support is suspended below a crane hook by several first ropes, and the test model is suspended below the main support by several second ropes. A movable support frame straddles the main support. The exciter's horizontal position is adjusted by adjusting the position of the first bolt on the main support, and its position is adjusted along the depth of the anechoic tank by a first position adjustment hole on the fixed support. An angle plate is parallel to the movable support frame, and a vibration damping structure and a dynamic vibration absorber are installed on the fixed support. By preventing vibration transmission and absorbing vibration energy, the structural vibration response caused by the exciter's operation is reduced.

Description

Technical Field

[0001] This invention relates to a low-vibration exciter fixing device and its usage method for anechoic water tank testing, belonging to the field of ship vibration and noise testing technology. Background Technology

[0002] Vibration and noise testing in anechoic water tanks is crucial for understanding the acoustic and vibration response characteristics of structures and controlling structural vibration and noise. Testing in anechoic water tanks reduces background noise interference, simulates free sound field conditions in an infinitely vast natural environment, and minimizes experimental errors. However, structural vibration and noise testing in anechoic water tanks typically requires excitation of the test model using a vibrator. Due to environmental limitations, existing vibrator mounting methods are relatively simple, requiring constant adjustments to the model's position to change the excitation measurement points. This is labor-intensive and prone to damaging the model, making flexible adjustment of the excitation point impossible. Furthermore, inaccurate installation height and position of the vibrator not only lead to inaccurate test data but also damage the test equipment and model. Therefore, designing a simple, flexible, and efficient vibrator mounting device for vibration and noise testing in anechoic water tanks is of great significance, allowing for flexible changes in the vibrator position based on the test model's hoisting and measurement point requirements. Additionally, since the vibrator itself is a significant excitation source, if the excitation frequency is close to the natural frequency of the entire mounting device, resonance can occur, negatively impacting the structural acoustic and vibration response testing.

[0003] A literature search of existing technologies revealed that the publicly available information related to this invention mainly includes: 1. A vibrator base fixing device (Patent No.: 202221468223.7); 2. A vibrator fixing device (Patent No.: 202022193982.4); 3. A movable modal vibrator fixing device (Patent No.: 200420086169.5).

[0004] A literature search of existing technologies revealed that, in recent years, the publicly available information related to this invention application mainly includes: 1. A vibrator base fixing device (Patent No.: 202221468223.7); 2. A vibrator fixing device (Patent No.: 202022193982.4); 3. A movable modal vibrator fixing device (Patent No.: 200420086169.5).

[0005] Patent application 1 discloses a vibrator base fixing device, belonging to the field of modal testing technology for automobiles and powertrains, solving the problem of difficult vibrator movement and installation. Patent application 2 discloses a vibrator fixing device, belonging to the field of helicopter testing equipment, which has the function of freely adjusting the installation height and angle of the vibrator within a certain range. The above two patent applications have different application fields and different specific structures than this invention, thus exhibiting significant differences. Patent application 3 discloses a movable modal vibrator bracket fixing device, enabling modal analysis of large equipment, which was previously only possible in the laboratory, to be performed in the field, expanding the application scope of modal testing, which differs significantly from this invention in application direction. Therefore, there is an urgent need for a low-vibration vibrator fixing device that can flexibly excite underwater structures in vibration and noise testing of anechoic pools, reduce the transmission of structural vibrations caused by the vibrator's operation, reduce test errors, and ensure the accuracy of test results. Summary of the Invention

[0006] This invention aims to solve the problems of traditional vibration and noise testing of anechoic water tanks, which cannot flexibly excite underwater structures and have a significant impact from the vibration transmission of the exciter itself. Therefore, it provides a low-vibration exciter fixing device and usage method for anechoic water tank testing.

[0007] The technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows:

[0008] A low-vibration exciter fixing device for anechoic water tank testing includes a main support, a movable support frame, a fixed support, an angle plate, several first ropes, and several second ropes. The main support is suspended below a crane hook via the first ropes, and the test model is suspended below the main support via the second ropes. The movable support frame straddles the main support, and both ends are fixed to the main support via first bolts. The position of the exciter in the horizontal direction is adjusted by adjusting the position of the first bolts on the main support. The exciter is fixed to the bottom of the fixed support, and the test model is fixed to the exciter via an excitation rod. The fixed support is fixed to the movable support frame via second bolts, and the position of the exciter in the depth direction of the anechoic water tank is adjusted via several first position adjustment holes on the fixed support. The angle plate is parallel to the movable support frame and magnetically connected to it. A vibration damping structure and a dynamic vibration absorber are installed on the fixed support.

[0009] Furthermore, the fixed bracket includes four bracket bodies arranged in a matrix and a fixed base fixed to the bottom of the four bracket bodies. A plurality of first position adjustment holes are respectively opened on the four bracket bodies and are arranged vertically on each bracket body.

[0010] Furthermore, the fixed bracket is also provided with two sets of crossbars, each set of crossbars being fixedly installed between the two bracket bodies.

[0011] Furthermore, the vibration damping structure includes a vibration damping loop square steel and four vibration damping mass square steels, wherein the vibration damping loop square steel is fixedly mounted on the upper surface of the fixed base, and the four vibration damping mass square steels are installed one-to-one on the lower part of the four support bodies.

[0012] Furthermore, the number of the dynamic vibration absorbers is four, and they are installed in the middle of the four support bodies.

[0013] Furthermore, the movable support frame includes two parallel support plates, each support plate having two ear plates fixedly installed along its length in the middle, and the second bolts being four in number, which are installed between the two support plates through the four ear plates. Each support plate has an end plate fixedly installed vertically and integrally at both ends, and the end plate has a fixing round hole.

[0014] Furthermore, the main support is a rectangular frame structure, which includes two parallel first support rods and two parallel second support rods. Each first support rod has a second position adjustment hole arranged along its length on its side wall, and a first bolt is correspondingly inserted into the second position adjustment hole.

[0015] Furthermore, both first support rods are hollow tubular structures, and each first support rod has a third position adjustment hole opened along its length on its upper wall. The two ends of the two support plates are inserted into the two third position adjustment holes in pairs.

[0016] Furthermore, the main support is evenly distributed with several lifting rings along its circumference. Each lifting ring has a first lifting hole and a second lifting hole respectively on its upper and lower parts. Several first ropes and several second ropes are connected to the main support through several first lifting holes and several second lifting holes respectively.

[0017] A method of using the above-mentioned vibrator fixing device includes the following steps:

[0018] Step 1: The crane lifts the main support using the crane hook and the first rope, and at the same time connects the test model to the main support using the second rope;

[0019] Step 2: Assemble the fixed bracket, vibrator, and vibrator rod;

[0020] Step 3: Based on the excitation position of the test model, adjust and fix the installation position of the fixed bracket on the movable support frame, and then adjust and fix the installation position of the movable support frame on the main support frame.

[0021] Step 4: Before starting the vibration and noise test of the silencing water tank, the natural frequency of the entire exciter fixing device is measured by simulation or test. The natural frequencies of the four dynamic vibration absorbers are adjusted to be the same as the first four natural frequencies of the fixing device.

[0022] Step 5: Place the test model into the silencing water tank using a crane, turn on the vibrator, and complete the test under the specified working conditions. After a set of working conditions is completed, rotate the main support according to the scale of the angle dial to complete the structural radiation noise test at different angles.

[0023] Step 6: Change the excitation point of the test model according to the test requirements, and repeat steps 3 to 5 to adjust the excitation position to meet the excitation requirements of any measuring point of the test model.

[0024] Compared with the prior art, the present invention has the following advantages:

[0025] The exciter fixing device of the present invention can realize external excitation of large structures.

[0026] The present invention has a simple structure, is easy to operate, saves time and effort, and is robust and reliable. Compared with the prior art, it is more suitable for the field needs of vibration and noise testing of anechoic water tanks.

[0027] The exciter fixing device of the present invention can adjust the position of the exciter in the horizontal and depth directions by adjusting the position of the movable support frame on the main support and the position of the fixed support frame on the movable support frame according to the excitation point of the test model. This allows for rapid and flexible adjustment of the excitation position of the exciter, meeting the condition of excitation from outside the test model for water tank vibration and noise testing. At the same time, by setting up a vibration damping structure, the transmission of structural vibration caused by the operation of the exciter is effectively reduced, effectively reducing test errors and ensuring the accuracy of test results. This is of great significance to the field of ship vibration and noise testing.

[0028] In this invention, by simultaneously arranging a vibration damping structure and a dynamic vibration absorber on a fixed support, the dynamic vibration absorber and the vibration damping structure together form a passive vibration control system, which reduces the structural vibration response caused by the exciter's operation by preventing vibration transmission and absorbing vibration energy.

[0029] During the testing process, test data needs to be collected by setting up hydrophones. By using the scale rotation device of the angle dial, the radiated noise test of the test model at different angles can be completed while reducing the number of hydrophones, effectively solving the problem of the test model's test conditions limitations. Attached Figure Description

[0030] Figure 1 This is a three-dimensional structural diagram of the present invention (the second rope is not shown);

[0031] Figure 2 A schematic diagram of the three-dimensional structure after the fixed bracket is assembled with the vibrator, vibration damping structure and dynamic vibration absorber;

[0032] Figure 3 This is a schematic diagram of the three-dimensional structure of the support plate;

[0033] Figure 4 A schematic diagram of the three-dimensional structure of the main support frame;

[0034] Figure 5 This is a schematic diagram of the three-dimensional structure of the angle disc;

[0035] Figure 6 This is a three-dimensional structural diagram of a dynamic vibration absorber.

[0036] In the picture:

[0037] 1. Main support; 1-1. First support rod; 1-11. Second position adjustment hole; 1-12. Third position adjustment hole; 1-2. Second support rod; 2. Movable support frame; 2-1. Support plate; 2-2. Ear plate; 2-3. End plate; 2-31. Fixed round hole; 3. Fixed support; 3-1. First position adjustment hole; 3-2. Support body; 3-3. Fixed base; 3-4. Crossbar; 4. Angle plate; 5. First rope; 6. Crane hook; 7. Test model; 8. Vibrator; 9. Vibration rod; 10. Vibration damping structure; 10-1. Vibration damping loop square steel; 10-2. Vibration damping mass square steel; 11. Dynamic vibration absorber; 12. Lifting ring; 12-1. First lifting hole; 12-2. Second lifting hole. Detailed Implementation

[0038] Specific implementation method one: Combining Figures 1-6 This description of embodiments provides a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0039] It should be noted that the descriptions of "front," "rear," "left," "right," "inner," "outer," "left side," "right side," "upper part," "lower part," "top," and "bottom" in this invention are defined based on the orientation or positional relationships shown in the accompanying drawings. They are merely for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the described structure must be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0040] In the description of this invention, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0041] A low-vibration exciter fixing device for anechoic water tank testing includes a main support 1, a movable support frame 2, a fixed support 3, an angle plate 4, several first ropes 5, and several second ropes. The main support 1 is suspended below a crane hook 6 via the first ropes 5, and the test model 7 is suspended below the main support 1 via the second ropes. The movable support frame 2 straddles the main support 1, and both ends of the movable support frame 2 are fixed to the main support 1 by first bolts. The exciter 8 is fixed by adjusting the position of the first bolts on the main support 1. The position is adjusted horizontally. The vibrator 8 is fixed at the bottom of the fixed bracket 3. The test model 7 and the vibrator 8 are fixedly connected by the vibrating rod 9. The fixed bracket 3 is fixed to the movable support frame 2 by the second bolt. The position of the vibrator 8 is adjusted along the depth direction of the silencing water tank by a number of first position adjustment holes 3-1 opened on the fixed bracket 3. The angle plate 4 is parallel to the movable support frame 2 and is magnetically connected to the movable support frame 2. The fixed bracket 3 is equipped with a vibration damping structure 10 and a dynamic vibration absorber.

[0042] The main support 1 is a circular frame structure or a rectangular frame structure, preferably a rectangular frame structure, which facilitates hoisting and positioning.

[0043] Both the first rope 5 and the second rope can be steel wire rope, elastic rope or any other rope capable of hoisting, preferably steel wire rope, to ensure a more reliable hoisting process.

[0044] The vibrator 8 is fixed to the fixed support by a third bolt. The vibrating rod 9 is a threaded rod.

[0045] In this invention, the position between the test model 7 and the main support 1 is relatively fixed by the action of the second rope. By adjusting the installation position of the fixed support 3 on the movable support frame 2, the position of the vibrator 8 in the height direction is adjusted, thereby adjusting the position between the vibrator 8 and the test model 7. The displacement direction of the movable support frame 2 in the horizontal direction is the same as the length direction of the test model 7. By adjusting the position of the movable support frame 2 in the horizontal direction, the position of the vibrator 8 in the horizontal direction is adjusted, thereby adjusting the connection position between the test model 7 and the vibrator 8.

[0046] Vibration damping mass is a technical means of setting up a structure in the vibration transmission path to effectively prevent the transmission of structural vibration. Compared with the structure itself, the vibration damping mass has a greater impedance, so that part of the bending wave that reaches the vibration damping mass is reflected back and part is transmitted through it, thereby achieving the purpose of isolating vibration. Therefore, by setting the vibration damping structure 10 on the fixed support 3, the present invention can effectively reduce or prevent the transmission of structural vibration caused by the exciter 8 itself when it is working, thereby reducing the structural vibration response caused by the exciter 8 when it is working and reducing the impact on the test results.

[0047] The exciter fixing device of the present invention can realize external excitation of large structures.

[0048] The present invention has a simple structure, is easy to operate, saves time and effort, and is robust and reliable. Compared with the prior art, it is more suitable for the field needs of vibration and noise testing of anechoic water tanks.

[0049] The exciter fixing device of the present invention can adjust the position of the exciter 8 in the horizontal and depth directions by adjusting the position of the movable support frame 2 on the main support 1 and the position of the fixed support 3 on the movable support frame 2 according to the excitation point of the test model 7. This allows for quick and flexible adjustment of the excitation position of the exciter 8, satisfying the condition for excitation from outside the test model 7 in water tank vibration and noise testing. At the same time, by setting the vibration damping structure 10, the transmission of structural vibration caused by the operation of the exciter 8 is effectively reduced, effectively reducing test errors and ensuring the accuracy of test results. This is of great significance in the field of ship vibration and noise testing.

[0050] The dynamic vibration absorber 11 is a simple cantilever beam type dynamic vibration absorber, which can flexibly adjust its natural frequency to absorb the vibration response of the main structure. Its specific structure is existing technology and will not be described in detail here. The cantilever beam type dynamic vibration absorber in this invention can be placed horizontally or vertically. When it is placed vertically, the mass block on it is fixedly connected to the cantilever beam. Before the fixed connection, it is necessary to ensure that the natural frequency of the fixing device is the same as that calculated in advance.

[0051] In this invention, by simultaneously arranging the vibration damping structure 10 and the dynamic vibration absorber 11 on the fixed bracket 3, the dynamic vibration absorber 11 and the vibration damping structure 10 together form a passive vibration control system, which reduces the structural vibration response caused by the exciter 8 when it is working by preventing vibration transmission and absorbing vibration energy.

[0052] During testing, hydrophones are used to collect test data. The scale rotation device of the angle dial 4 allows for the completion of noise tests at different angles of the test model 7 while reducing the number of hydrophones required, effectively solving the problem of limitations in the testing conditions of the test model 7. For example, if it is necessary to test the noise of the test model 7 at 90 degrees, 180 degrees, 270 degrees, and 360 degrees, the original exciter fixing device would require rotating the hydrophones at 90 degrees, 180 degrees, 270 degrees, and 360 degrees respectively, requiring four hydrophones. However, with the exciter fixing device of this invention, only one hydrophone needs to be placed at one angle. After testing the noise at one angle, the main support 1 can be hoisted using the crane hook 6, and the angle dial 4 can be used to determine the rotation angle to proceed to the next angle for noise testing.

[0053] The exciter fixing device of the present invention is a detachable structure, and the disassembly operation is simple and reusable. That is, the same exciter fixing device can be used when different test models 7 are replaced, which provides convenient conditions for structural disturbance noise testing. It is of great significance to the field of ship vibration and noise testing and has high economic efficiency.

[0054] The fixed bracket 3 includes four bracket bodies 3-2 arranged in a matrix and fixed bases 3-3 fixed to the bottom of the four bracket bodies 3-2. A plurality of first position adjustment holes 3-1 are respectively formed on the four bracket bodies 3-2, and are arranged vertically on each bracket body 3-2. With this design, the first position adjustment holes 3-1 can be through holes or threaded holes. When the first position adjustment hole 3-1 is a through hole, the position is fixed with the assistance of a nut; when the first position adjustment hole 3-1 is a threaded hole, the position can be fixed directly by tightening the first bolt. Each bracket body 3-2 is an angle steel structure, and the first position adjustment holes 3-1 are formed on its side wall. By setting the bracket body 3-2 as an angle steel structure, the overall weight of the fixed bracket 3 is effectively reduced. The fixed base 3-3 has a plurality of bolt holes for installing the vibrator 8, preferably four bolt holes. The fixed base 3-3 is preferably welded to the bracket body 3-2.

[0055] The fixed bracket 3 is also provided with two sets of crossbars 3-4, each set of crossbars 3-4 being fixedly installed between two bracket bodies 3-2. This design allows the two sets of crossbars 3-4 to act as handrails, facilitating the adjustment of the height of the fixed bracket 3, and consequently, the height of the vibrator 8. The two sets of crossbars 3-4 are preferably arranged symmetrically, with one set fixed between two adjacent bracket bodies 3-2 and the other set fixed between the remaining two adjacent bracket bodies 3-2. Each set of crossbars 3-4 is preferably arranged vertically for easy gripping.

[0056] The vibration damping structure 10 includes a vibration damping loop square steel 10-1 and four vibration damping mass square steels 10-2. The vibration damping loop square steel 10-1 is fixed to the upper surface of the fixed base 3-3, and the four vibration damping mass square steels 10-2 are installed one-to-one on the lower part of the four support bodies 3-2. In this design, both the vibration damping loop square steel 10-1 and each vibration damping mass square steel 10-2 are solid structures. When the support body 3-2 is an angle steel structure, the vibration damping mass square steel 10-2 is installed on the inner side of the angle steel structure. By setting the vibration damping mass square steel 10-2 at the lower part of the four support bodies 3-2, the vibration transmitted by the support body 3-2 during the operation of the exciter 8 is effectively reduced, thus reducing the impact on the test results. Furthermore, by setting the vibration damping loop square steel 10-1, the vibration transmitted by the fixed base 3-3 during the operation of the exciter 8 is effectively reduced, thereby further reducing the structural vibration response caused by the operation of the exciter 8 and reducing the impact on the test results.

[0057] The number of the dynamic vibration absorbers 11 is four, and they are installed in the middle of the four support bodies 3-2.

[0058] The movable support frame 2 includes two parallel support plates 2-1. Each support plate 2-1 has two ear plates 2-2 fixed along its length at its center. Four second bolts are used, corresponding to the four ear plates 2-2, and are installed between the two support plates 2-1. Each support plate 2-1 has a vertically fixed end plate 2-3 at both ends, with a fixing hole 2-31 on the end plate 2-3. With this design, the four support bodies 3-2 are installed on the two support plates 2-1 in pairs, and the height of the fixed support 3 is adjusted through several vertically arranged first position adjustment holes 3-1. According to the testing requirements of the test model 7, the movable support frame 2 is moved to the designated excitation position along the length of the test model 7, and then connected to the main support 1 through the first bolts and fixing holes 2-31. The four second bolts are correspondingly installed on the four ear plates 2-2.

[0059] The main support 1 is a rectangular frame structure, comprising two parallel first support rods 1-1 and two parallel second support rods 1-2. Each first support rod 1-1 has a second position adjustment hole 1-11 arranged along its length on its side wall, and a first bolt is inserted into the corresponding second position adjustment hole 1-11. This design allows for position adjustment of the movable support frame 2 along the length of the first support rod 1-1 by adjusting the position of the first bolt within the second position adjustment hole 1-11. The length direction of the two first support rods 1-1 is the same as the length direction of the test model 7. The first support rods 1-1 and second support rods 1-2 are preferably fixed together by welding to form a rectangular frame structure. The second position adjustment hole 1-11 is an elongated hole. The number and position of the second position adjustment holes 1-11 on each first support rod 1-1 can be either one on one side wall of the first support rod 1-1 or two symmetrically arranged on both side walls of the first support rod 1-1, which facilitates the positioning of the first bolt.

[0060] Both first support rods 1-1 are hollow tubular structures. Each first support rod 1-1 has a third position adjustment hole 1-12 along its length on its upper wall. The two ends of the two support plates 2-1 are inserted into the two third position adjustment holes 1-12 in pairs. This design, using a hollow tubular structure, effectively reduces the overall weight of the device. Specifically, the first support rod can be a round tube or a square tube, preferably a square tube, to effectively reduce the structural area occupied. Inserting the two ends of the two support plates 2-1 into the third position adjustment holes 1-12 in pairs further ensures a stable connection of the device. The third position adjustment hole 1-12 is an elongated hole. The two ends of the two support plates 2-1 are the end plates 2-3. To further ensure the strength of the first support rod 1-1, it can also be a rod-shaped structure, with the third position adjustment holes 1-12 formed on its upper surface and arranged along its length.

[0061] The main support 1 has a plurality of lifting rings 12 evenly distributed along its circumference. Each lifting ring 12 has a first lifting hole 12-1 and a second lifting hole 12-2 respectively on its upper and lower parts. A plurality of first ropes 5 and a plurality of second ropes are connected to the main support 1 through the plurality of first lifting holes 12-1 and the plurality of second lifting holes 12-2 respectively. In this design, the number of lifting rings 12, first ropes 5 and second ropes are all set in the same manner. Preferably, there are four, which are respectively arranged at the four corner positions of the main support 1. The lifting rings 12 are preferably welded to the main support 1.

[0062] A method of using the above-mentioned vibrator fixing device includes the following steps:

[0063] Step 1: The crane lifts the main support 1 using the crane hook 6 and the first rope 5, and at the same time connects the test model 7 to the main support 1 using the second rope.

[0064] Step 2: Assemble the fixed bracket 3, vibrator 8, and vibrating rod 9;

[0065] Step 3: According to the excitation position of the test model 7, adjust and fix the installation position of the fixed bracket 3 on the movable support frame 2, and then adjust and fix the installation position of the movable support frame 2 on the main support 1.

[0066] Step 4: Before starting the vibration and noise test of the silencing water tank, the natural frequency of the entire exciter fixing device is measured by simulation or test. The natural frequencies of the four dynamic vibration absorbers 11 are adjusted to be the same as the first four natural frequencies of the fixing device. When the exciter 8 is working, the dynamic vibration absorbers 11 can effectively reduce the vibration response of the entire exciter fixing device and reduce the test error.

[0067] Step 5: Place the test model 7 into the silencing water tank using a crane, turn on the vibrator 8, and complete the test under the specified working conditions. After a set of working conditions tests are completed, rotate the main support 1 according to the scale of the angle plate 4 to complete the structural radiation noise test at different angles; this solves the problem of the test model 7 being limited in working conditions due to the limited number of hydrophones arranged around the perimeter.

[0068] Step 6: Replace the excitation point of test model 7 according to the test requirements, and repeat steps 3 to 5 to adjust the excitation position so as to meet the excitation requirements of any measuring point of test model 7.

[0069] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A low-vibration exciter fixing device for anechoic water tank testing, characterized in that: It includes a main support (1), a movable support frame (2), a fixed support (3), an angle plate (4), several first ropes (5) and several second ropes. The main support (1) is suspended below the crane hook (6) by several first ropes (5), and the test model (7) is suspended below the main support (1) by several second ropes. Through the action of the second ropes, the position between the test model (7) and the main support (1) is relatively fixed. The movable support frame (2) straddles the main support frame (1), and both ends of the movable support frame (2) are fixed to the main support frame (1) by first bolts. The position of the vibrator (8) in the horizontal direction is adjusted by adjusting the position of the first bolts on the main support frame (1). The vibrator (8) is fixed to the bottom of the fixed support frame (3). The test model (7) and the vibrator (8) are fixed together by the vibrating rod (9). The fixed support frame (3) is fixed to the movable support frame (2) by second bolts, and the fixed support frame (3) is fixed to the movable support frame (2) by openings in the fixed support frame (3). The first position adjustment holes (3-1) on the exciter (8) are used to adjust the position of the exciter (8) along the depth direction of the silencing water tank. The angle plate (4) is erected parallel to the movable support frame (2) and the angle plate (4) is magnetically connected to the movable support frame (2). The test model (7) is placed into the silencing water tank by a crane, the exciter (8) is turned on, and the test under the specified working conditions is completed. After a set of working condition tests is completed, the main support (1) is rotated according to the scale of the angle plate (4) to complete the structural radiation noise test under different angles. The fixed bracket (3) is equipped with a vibration damping structure (10) and a dynamic vibration absorber; The fixed bracket (3) includes four bracket bodies (3-2) arranged in a matrix and a fixed base (3-3) fixed to the bottom of the four bracket bodies (3-2). A plurality of first position adjustment holes (3-1) are respectively opened on the four bracket bodies (3-2) and are arranged vertically on each bracket body (3-2). The vibration damping structure (10) includes a vibration damping loop square steel (10-1) and four vibration damping mass square steels (10-2), wherein the vibration damping loop square steel (10-1) is fixedly mounted on the upper surface of the fixed base (3-3), and the four vibration damping mass square steels (10-2) are installed one-to-one on the lower part of the four support bodies (3-2). The number of the dynamic vibration absorbers (11) is four, and they are installed in the middle of the four support bodies (3-2).

2. The low-vibration exciter fixing device for anechoic water tank testing according to claim 1, characterized in that: The fixed bracket (3) is also provided with two sets of crossbars (3-4), and each set of crossbars (3-4) is fixedly installed between the two bracket bodies (3-2).

3. The low-vibration exciter fixing device for anechoic water tank testing according to claim 1, characterized in that: The movable support frame (2) includes two parallel support plates (2-1). Each support plate (2-1) has two ear plates (2-2) fixed in the middle along its length. The second bolt has four bolts, which are installed between the two support plates (2-1) through the four ear plates (2-2). Each support plate (2-1) has an end plate (2-3) fixed vertically and integrally at both ends. The end plate (2-3) has a fixing hole (2-31).

4. The low-vibration exciter fixing device for anechoic water tank testing according to claim 1, characterized in that: The main support (1) is a rectangular frame structure, which includes two parallel first support rods (1-1) and two parallel second support rods (1-2). Each first support rod (1-1) has a second position adjustment hole (1-11) arranged along its length on its side wall, and a first bolt is inserted into the second position adjustment hole (1-11).

5. The low-vibration exciter fixing device for anechoic water tank testing according to claim 4, characterized in that: Both first support rods (1-1) are hollow tubular structures. Each first support rod (1-1) has a third position adjustment hole (1-12) along its length on its upper wall. The two ends of the two support plates (2-1) are inserted into the two third position adjustment holes (1-12) respectively.

6. The low-vibration exciter fixing device for anechoic water tank testing according to claim 1, characterized in that: The main support (1) has several lifting rings (12) evenly distributed around its circumference. Each lifting ring (12) has a first lifting hole (12-1) and a second lifting hole (12-2) respectively on its upper and lower parts. Several first ropes (5) and several second ropes are connected to the main support (1) through several first lifting holes (12-1) and several second lifting holes (12-2).

7. A method of using the vibrator fixing device according to any one of claims 1 to 6, characterized in that: Includes the following steps: Step 1: The crane lifts the main support (1) using the crane hook (6) and the first rope (5), and at the same time connects the test model (7) to the main support (1) using the second rope; Step 2: Assemble the fixed bracket (3), vibrator (8) and vibrator rod (9); Step 3: According to the excitation position of the test model (7), adjust and fix the installation position of the fixed bracket (3) on the movable support frame (2), and then adjust and fix the installation position of the movable support frame (2) on the main support frame (1); Step 4: Before starting the vibration and noise test of the silencing water tank, the natural frequency of the entire exciter fixing device is measured by simulation or test. The natural frequencies of the four dynamic vibration absorbers (11) are adjusted to be the same as the first four natural frequencies of the fixing device. Step 5: Place the test model (7) into the silencing water tank using a crane, turn on the vibrator (8), and complete the test under the specified working conditions. After a set of working conditions tests are completed, rotate the main support (1) according to the scale of the angle plate (4) to complete the structural radiation noise test under different angles. Step 6: Change the excitation point of the test model (7) according to the test requirements, and repeat steps 3 to 5 to achieve the adjustment of the excitation position so as to meet the excitation requirements of any measuring point of the test model (7).

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