A flow-induced vibration noise test device and method based on a circulating water tank

Abstract

The application provides a kind of flow-induced vibration noise test device and method based on circulating water tank, belong to underwater vehicle test measurement field.Solve the current problem of no flow-induced vibration and noise test device can be measured simultaneously.It includes reverberation tank, circulating water tank, model hoisting device, model angle of attack adjusting device and signal acquisition device;The circulating water tank is a back shape structure, the circulating water tank includes sequentially arranged and interconnected working section, first rectifier section, power section, second rectifier section and third rectifier section, the rectifier grid is arranged in the rectifier section, the propeller is arranged in the power section, the working section of the circulating water tank is a straight section and is arranged at the upper end of the reverberation tank, the observation window is opened on the working section, the flow velocity sensing sensor is installed on the wall surface at the starting position of the working section, the underwater camera is arranged in the reverberation tank, and the flow field characteristics around the test model are shot through the observation window on the circulating water tank.The application is suitable for simultaneously measuring flow-induced vibration noise of underwater vehicle test.

Description

Technical Field

[0001] This invention belongs to the field of underwater vehicle testing and measurement, and in particular relates to a flow-induced vibration noise testing device and method based on a circulating water tank. Background Technology

[0002] Traditional circulating water tanks are unsuitable for measuring the vibration and noise of underwater vehicles due to their complex structure, applicability only to small-scale models, and inability to adjust the model's angle of attack. During experimental measurements, vibrations from the model's fixing devices are transmitted to the circulating water tank, leading to significant errors in the measurement results. Furthermore, traditional reverberation tanks are primarily used to measure the mechanical noise of underwater vehicles, but cannot measure the vibration and noise generated by structures under turbulent pressure excitation, nor can they measure larger-scale vehicles. Therefore, designing an experimental device capable of measuring both the drag and strain of underwater vehicles, as well as their vibration and noise, is of great significance for the study of flow-induced vibration and noise problems.

[0003] A review of existing literature and patents revealed a scarcity of research on vibration and noise testing in circulating water tanks. Related to this invention is a flow-induced noise testing device for airfoil structures based on circulating water tanks. This device uses a fixed section on the circulating water tank to mount the test piece and adjusts the angle of attack of the airfoil structure via an angle-of-attack adjustment device. However, compared to this patent, the angle-of-attack adjuster of this device is only applicable to airfoil structures, and it cannot measure the flow-induced noise of the test device. Another invention is a flow-induced noise measurement device for underwater vehicles based on gravity tunnels. This device fixes the experimental device to the working section of the gravity tunnel, with a reverberation tank installed outside the working section. It can measure the flow-induced noise of the reverberation tank. Noise can be deduced from the flow-induced noise of underwater vehicles. Compared with this patent, this device cannot adjust the angle of attack of the measurement model and can only measure fully enclosed underwater vehicles, not the underwater noise of surface ships. At the same time, due to the characteristics of gravity-type water tunnels, it cannot measure the noise of vehicles in low-speed flow. There is also a new type of active vibration reduction low-noise flow-induced vibration noise test device. This device uses a movable trailer and vibration measurement device installed on a towed pool to measure the vibration characteristics of a large-scale model. Compared with this patent, this device cannot measure flow-induced noise, and because the trailer needs to move continuously during the test, the background vibration has a greater impact on the test measurement results.

[0004] In summary, there are significant differences between the currently published literature and patents and this invention, and there is currently no experimental device capable of simultaneously measuring flow-induced vibration and noise. Therefore, this invention proposes a novel flow-induced vibration and noise measurement device based on a circulating water tank. Summary of the Invention

[0005] In view of this, the present invention aims to provide a flow-induced vibration and noise testing device based on a circulating water tank, so as to solve the problem that there is currently no testing device that can simultaneously measure flow-induced vibration and noise.

[0006] To achieve the above objectives, the technical solution created by this invention is implemented as follows:

[0007] A flow-induced vibration noise testing system based on a circulating water tank includes a reverberation tank, a circulating water tank, a model hoisting device, a model angle of attack adjustment device, and a signal acquisition device;

[0008] The circulating water tank has a U-shaped structure and includes a working section, a first rectification section, a power section, a second rectification section, and a third rectification section arranged sequentially and interconnected. The rectification section is equipped with a rectification grid to adjust the flow direction of the fluid in the circulating water tank. The power section is equipped with a propeller. The working section of the circulating water tank is a straight section and is located at the upper end of the reverberation tank. An observation window is opened on the working section. A flow velocity sensing sensor is installed on the wall at the starting position of the working section. An underwater camera is installed in the reverberation tank to capture the flow field characteristics around the test model through the observation window on the circulating water tank.

[0009] The model hoisting device includes two trusses, two cranes, and two installation platforms. The two trusses are arranged facing each other. Truss pulleys are installed at the bottom of the trusses. Two support plates are symmetrically arranged on both sides of the working section of the circulating water tank. Crane rails that cooperate with the truss pulleys at the bottom of the trusses are provided on the support plates. The trusses move on the crane rails through the truss pulleys. The top of each truss is connected to a crane through the rails. The cranes are connected to the corresponding installation platforms through hooks.

[0010] Two opposing circulating water tank slide rails are provided at the upper end of the working section of the circulating water tank, and the bottom of the installation platform cooperates with the circulating water tank slide rails through a slider.

[0011] The model angle of attack adjustment device includes two electric lifting mechanisms, two universal joints and two connecting pipes. One electric lifting mechanism is arranged on each mounting platform. The output end of the electric lifting mechanism passes through the corresponding mounting platform and is connected to a universal joint. The test model is connected to the two universal joints through two connecting pipes.

[0012] The signal acquisition device includes a command sending unit, a signal acquisition unit, and a data storage unit. The command sending unit is connected to the signal acquisition unit via a signal transmission line, and the signal acquisition unit is connected to the data storage unit via a signal transmission line. The signal acquisition unit includes a pressure sensor, an acceleration sensor, a strain gauge, and a hydrophone. The hydrophone is installed inside a reverberation tank, while the pressure sensor, acceleration sensor, and strain gauge are all installed inside the test model.

[0013] Furthermore, the reverberation water tank includes a tank body, with a water inlet at the top of the tank body and a drain outlet at the bottom of the tank body. The inner wall of the tank body is covered with sound-absorbing wedges, and the top of the tank body has an opening for supporting the working section of the circulating water tank.

[0014] Furthermore, the circulating water tank propeller is mounted on the circulating water tank wall via bearings, and a drive motor is installed externally. The first and third rectification sections are annular sections, the second rectification section is a straight section, and the rectification grid includes a flat guide plate and an annular guide plate. The flat guide plate is arranged in the second rectification section, and an annular guide plate is arranged in both the first and third rectification sections.

[0015] Furthermore, the electric lifting mechanism includes a drive motor, a lifting transmission assembly, and a lifting rod. The drive motor is connected to the mounting platform via bolts. The output end of the drive motor is connected to the lead screw in the lifting transmission assembly via a worm gear. A lead screw is fitted with a lead screw nut, and the lifting rod is mounted on the lead screw nut. The lower end of the lifting rod passes through the mounting platform and is connected to the test model via a universal joint. The lifting transmission assembly also includes a guide component for the up-and-down movement of the lead screw nut.

[0016] Furthermore, the universal joint can perform six degrees of freedom motion. When measuring the fixed angle of attack, the universal joints at the front and rear of the test model are locked to fix the model in the designated position. When the angle of attack needs to be adjusted, the universal joints at the front and rear of the model are opened, and the length of the lifting rod is adjusted by the electric lifting mechanism located at the head of the test model to adjust the test model to the designated angle of attack and lock the universal joints to fix the position of the test model.

[0017] Furthermore, the upper end of the universal joint is connected to the lifting rod by a thread, the lower end of the universal joint is provided with a slot, and the connecting pipe above the model is provided with a protrusion, which fixes the test model by the cooperation of the protrusion and the slot.

[0018] Furthermore, vibration isolation pads are provided between the circulating water tank slide rail and the installation platform, and vibration isolation pads are also provided between the circulating water tank and the reverberation water tank.

[0019] Furthermore, a sound insulation panel is installed on the outer wall of the power section of the circulating water tank.

[0020] Furthermore, the observation window is installed in the middle area of ​​the working section using bolts and silicone sealant.

[0021] Another objective of this invention is to provide a testing method for a vibration and noise testing device based on a circulating water tank, specifically including the following steps:

[0022] Step 1: Fill the circulating water tank and reverberation water tank with still water;

[0023] Step 2: Turn on the drive motor of the propeller, start the signal acquisition device, and record the background vibration and background noise of the circulating water tank at different flow rates. After measuring the flow rate three times for each group, turn off the drive motor of the circulating water tank propeller and the signal acquisition device.

[0024] Step 3: Adjust the position of the crane on the slide rail according to the size of the test model, install the test model below the lifting rod, use the crane to lift the installation platform to the designated position and fix it with bolts, and lock the universal joint;

[0025] Step 4: Turn on the thruster's drive motor again, start the signal acquisition device, wait for the flow velocity sensor value to stabilize, and record the sampling signals from the flow velocity sensor, pressure sensor, acceleration sensor, and hydrophone. After measuring the same flow velocity three times, turn off the thruster's drive motor and the signal acquisition device again.

[0026] Step 5: Adjust the angle of attack of the test model by using the universal joint and the lifting rod, and repeat Step 3 and Step 4 3 times to complete the experimental measurement under different angles of attack;

[0027] Step 6: Remove the test model and sensors, turn off the drive motor and signal acquisition device of the thruster, and drain the water from the reverberation tank and circulating water tank.

[0028] Compared with the prior art, the beneficial effects of the flow-induced vibration noise testing device based on a circulating water tank described in this invention are:

[0029] (1) The present invention provides a flow-induced vibration noise test device based on a circulating water tank, which enables free adjustment of the overall position and angle of attack of the model through a truss, a mounting platform, a lifting rod and a universal joint;

[0030] By installing vibration damping pads on the slider and the reverberation tank, the vibration transmission between the circulating water tank, the reverberation tank, and the installation platform is reduced, thereby reducing test errors.

[0031] By installing sound-absorbing wedges on the inner wall of the reverberation tank and sound-insulating materials on the wall of the circulating water tank, the background noise of the test system is reduced, and the entire system can operate with low noise.

[0032] By installing different types of sensors on and inside the model, the test apparatus can measure the model's sailing resistance, stress distribution, vibration response, and flow-induced noise.

[0033] (2) The present invention provides a new method for measuring the flow-induced vibration noise of test models under different angles of attack. Moreover, the present invention can also measure the internal strain of the structure.

[0034] (3) The flow-induced vibration and noise test device based on the circulating water tank described in this invention has the advantages of simple structure, easy operation, low vibration, low noise and good stability, which is of great significance for vibration and noise testing of ships and underwater vehicles. Attached Figure Description

[0035] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments and descriptions of the invention are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0036] Figure 1 A three-dimensional structural schematic diagram of a flow-induced vibration noise testing device based on a circulating water tank, as described in an embodiment of the present invention;

[0037] Figure 2 A perspective view of the model hoisting system and angle of attack adjustment system in a flow-induced vibration noise testing device based on a circulating water tank, as described in an embodiment of the present invention;

[0038] Figure 3 A schematic diagram of the universal joint in the angle-of-attack adjustment system described in the embodiment of the present invention;

[0039] Figure 4 A schematic diagram of the slider and vibration damping pad in a flow-induced vibration noise testing device based on a circulating water tank, as described in an embodiment of the present invention;

[0040] Figure 5 A flowchart illustrating the testing method of a flow-induced vibration noise testing device based on a circulating water tank, as described in an embodiment of the present invention;

[0041] Figure 6 A schematic diagram showing the measurement results of the pulsating pressure on the surface of the test model under different flow rates;

[0042] Figure 7 This is a schematic diagram showing the measurement results of vibration acceleration of the test model under different flow velocities.

[0043] Explanation of reference numerals in the attached figures:

[0044] 1. Circulating water tank; 2. Reverberation tank; 3. Model hoisting device; 31. Truss; 32. Crane; 4. Model angle of attack adjustment device; 41. Drive motor; 42. Lifting transmission assembly; 43. Lifting rod; 44. Universal joint; 45. Test model; 46. Installation platform; 5. Thruster; 6. Straight guide plate; 7. Annular guide plate; 8. Sound-absorbing wedge; 9. Crane slide rail; 10. Observation window; 11. Flow velocity sensor; 12. Circulating water tank slide rail; 13. Slider; 14. Vibration isolation pad; 15. Truss pulley; 16. Signal acquisition device. Detailed Implementation

[0045] The technical solution of this invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only a part of, and not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without inventive effort are within the scope of protection of this invention.

[0046] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0047] In the description of this invention, it should be noted that, unless otherwise explicitly 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 mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0048] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0049] like Figures 1-4 As shown, a flow-induced vibration noise test device based on a circulating water tank includes a reverberation water tank 2, a circulating water tank 1, a model hoisting device 3, a model angle of attack adjustment device 3, and a signal acquisition device 16.

[0050] The circulating water tank 1 has a U-shaped structure and includes a working section, a first rectification section, a power section, a second rectification section, and a third rectification section arranged sequentially and interconnected. A rectification grid is provided in the rectification section to adjust the flow direction of the fluid in the circulating water tank 1. A propeller 5 is provided in the power section. By changing the rotation speed of the propeller 5 in the circulating water tank, the fluid velocity in the circulating water tank 1 can be autonomously adjusted. The working section of the circulating water tank 1 is a straight section and is located at the upper end of the reverberation tank 2. An observation window 10 is provided on the working section. A flow velocity sensing sensor 11 is installed on the wall at the starting position of the working section. The flow velocity sensing sensor 11 can monitor the initial flow velocity of the working section of the circulating water tank in real time. An underwater camera is provided in the reverberation tank 2 to capture the flow field characteristics around the test model 45 through the observation window 10 on the circulating water tank 1.

[0051] The model hoisting device 3 includes two trusses 31, two cranes 32, and two installation platforms 46. The two trusses 31 are arranged facing each other. Truss pulleys 15 are installed at the bottom of the trusses 31. Two support plates are symmetrically arranged on both sides of the working section of the circulating water tank 1. Crane rails 9 that cooperate with the truss pulleys 15 at the bottom of the trusses 31 are provided on the support plates. The trusses 31 move on the crane rails 9 through the truss pulleys 15. The top of each truss 31 is connected to a crane 32 through the rail. The crane 32 is connected to the corresponding installation platform 46 through the hook.

[0052] Two opposing circulating water tank slide rails 12 are provided at the upper end of the working section of the circulating water tank 1, and the bottom of the mounting platform 46 cooperates with the circulating water tank slide rails 12 through the slider 13.

[0053] The model angle of attack adjustment device 4 includes two electric lifting mechanisms, two universal joints 44, and two connecting pipes. One electric lifting mechanism is arranged on each mounting platform 46. The output end of the electric lifting mechanism passes through the corresponding mounting platform 46 and is connected to a universal joint 44. The test model 45 is connected to the two universal joints 44 through the two connecting pipes. The universal joints 44 can be locked after being adjusted to the required position. The universal joints and their locking-related structures are existing structures, and their specific structural composition and working principle will not be described in detail here. The vertical movement of the test model is controlled by the lifting rods installed at the front and rear ends of the test model 45. The front and rear lifting rods are independently controlled, which allows the test model 45 to freely adjust the angle of attack. When used in conjunction with the flow velocity sensing sensor 11, it can realize the measurement of the vibration and sound radiation characteristics of the model under different angles of attack and flow velocities.

[0054] The signal acquisition device 16 includes a command sending unit, a signal acquisition unit, and a data storage unit. The command sending unit is connected to the signal acquisition unit via a signal transmission line, and the signal acquisition unit is connected to the data storage unit via a signal transmission line. The signal acquisition unit includes a pressure signal acquisition unit, a vibration acquisition unit, a stress signal acquisition unit, and a noise signal acquisition unit. The pressure signal acquisition unit includes a pressure sensor, the vibration acquisition unit includes an accelerometer, the stress signal acquisition unit includes a strain gauge, and the noise signal acquisition unit includes a hydrophone.

[0055] The hydrophone is installed inside the reverberation tank 2, and the pressure sensor, acceleration sensor, and strain gauge are all installed inside the test model 45. It can measure multiple physical quantities simultaneously without interference between the sensors. During the test, the command sending unit sends commands to each sensor, sets the sensor sensitivity, and records data. The signal acquisition unit transmits the acquired time-domain signal to the data storage unit through the signal transmission line and can perform real-time processing. The command sending unit, signal acquisition unit, and data storage unit are all existing structures, and their working principles are also existing. Their specific structural composition and working principles will not be described in detail here.

[0056] The reverberation water tank 2 includes a tank body, with a water inlet at the top and a drain outlet at the bottom. The inner wall of the tank body is covered with sound-absorbing wedges 8, and the top of the tank body has an opening for supporting the working section of the circulating water tank 1.

[0057] The propeller of the circulating water tank 1 is mounted on the wall of the circulating water tank 1 via bearings, and a drive motor 41 is installed externally. The first and third rectification sections are annular sections, and the second rectification section is a straight section. The rectification grid includes a flat guide plate 6 and an annular guide plate 7. The flat guide plate 6 is arranged in the second rectification section, and the annular guide plate 7 is arranged in both the first and third rectification sections. The flow direction of the fluid in the circulating water tank is adjusted by the shape guidance method.

[0058] The electric lifting mechanism includes a drive motor 41, a lifting transmission assembly 42, and a lifting rod 43. The drive motor 41 is connected to the mounting platform 46 by bolts. The output end of the drive motor 41 is connected to the lead screw in the lifting transmission assembly 42 through a worm gear. A lead screw is fitted with a lead screw nut, and the lifting rod 43 is mounted on the lead screw nut. The lower end of the lifting rod 43 passes through the mounting platform 46 and is connected to the test model 45 through a universal joint 44. The lifting transmission assembly 42 also includes a guide for the up and down movement of the lead screw nut.

[0059] The universal joint 44 can perform six degrees of freedom of movement. When measuring the fixed angle of attack, the two universal joints 44 at the front and rear of the test model 45 are locked to fix the model in the designated position. When it is necessary to adjust the angle of attack, the two universal joints 44 at the front and rear of the model are opened, and the length of the lifting rod 43 is adjusted by the electric lifting mechanism located at the head of the test model 45 to adjust the test model 45 to the designated angle of attack and lock the universal joint 44 to fix the position of the test model 45.

[0060] The upper end of the universal joint 44 is connected to the lifting rod 43 by a thread, and the lower end of the universal joint 44 is provided with a slot. The connecting pipe above the model is provided with a protrusion, and the test model 45 is fixed by the cooperation of the protrusion and the slot.

[0061] Vibration isolation pads 14 are installed between the circulating water tank slide rail 12 and the mounting platform 46 to prevent vibration transmission between the mounting platform and the circulating water tank, effectively reducing vibration transmission between different areas and minimizing test errors. Vibration isolation pads 14 are also installed between the circulating water tank 1 and the reverberation tank 2 to prevent vibration from the circulating water tank from being transmitted to the reverberation tank. Sound insulation plates are installed on the outer wall of the power section of the circulating water tank 1 to effectively isolate the noise of the propeller and drive motor, reducing noise measurement test errors. The observation window 10 is installed in the middle area of ​​the working section by bolts and glass glue. The observation window is made of tempered glass with good projection performance. An underwater camera is arranged inside the reverberation tank 2, which can capture the flow field characteristics around the test model through the observation window.

[0062] A flow velocity sensor is installed at the initial position of the working section of the circulating water tank, where a vibration isolation device is installed at the connection point. This sensor measures the inflow velocity at the inlet of the working section in real time, providing parameters for numerical simulation and reducing the error of the test results. The pressure sensor and vibration acceleration sensor are installed inside the model, and the hydrophone is arranged at a designated position in the reverberation tank. The collected signals are converted into electrical signals by a signal processor and stored in the data storage unit.

[0063] Figure 5 As shown, a test method for a flow-induced vibration noise test device based on a circulating water tank specifically includes the following steps:

[0064] Step 1: Close the drain outlet of reverberation water tank 2, and fill the circulating water tank 1 and reverberation water tank 2 with still water;

[0065] Step 2: Turn on the propeller drive motor and start the signal acquisition device 16 to record the background vibration and background noise of the circulating water tank 1 at different flow rates. After each set of flow rate measurements is performed three times, turn off the propeller drive motor and the signal acquisition device 16. In Step 2, the propeller drive motor of the circulating water tank can adjust the propeller speed. When used in conjunction with the flow rate sensor, it can continuously measure the results at different flow rates, thereby improving the experimental efficiency.

[0066] Step 3: Adjust the position of the crane on the slide rail according to the size of the test model 45, install the test model 45 below the lifting rod 43, use the crane to lift the installation platform 46 to the designated position and fix it with bolts, and lock the universal joint 44.

[0067] Step 4: Turn on the drive motor of the thruster again, start the signal acquisition device 16, wait for the value of the flow velocity sensor 11 to stabilize, record the sampling signals of the flow velocity sensor, pressure sensor, acceleration sensor, strain gauge and hydrophone. After measuring the same flow velocity three times, turn off the drive motor of the thruster and the signal acquisition device 16 again.

[0068] Step 5: Adjust the angle of attack of the test model 45 by cooperating with the universal joint 44 and the lifting rod 43, and repeat steps 3 and 4 3 times to complete the experimental measurement under different angles of attack;

[0069] Step 6: Remove the test model 45 and the sensor, turn off the drive motor of the thruster and the signal acquisition device 16, and drain the water from the reverberation tank 2 and the circulating water tank 1.

[0070] The following is a test method for a flow-induced vibration noise test device based on a circulating water tank, which specifically includes the following steps:

[0071] Taking a circulating water tank 1 with a length of 15m, a width of 9m, and an inner wall spacing of 1.5m and a reverberation water tank 2 with a length of 6m and a width of 5m as examples, the novel vibration and noise testing device and method of the present invention will be described in detail.

[0072] 1) Close the drain outlets of circulating water tank 1 and reverberation water tank 2, open the inlet outlets of circulating water tank 1 and reverberation water tank 2, and fill circulating water tank 1 and reverberation water tank 2 with still water;

[0073] 2) Select a B&K 8101 hydrophone and place it in the reverberation tank 2, 0.6m away from the working section. Start the signal acquisition device 16, connect the flow velocity sensor 11 to the host computer, turn on the thruster 5, set the initial speed to 500 rad / min, read the flow velocity signal of the flow velocity sensor 11, and adjust the speed of the thruster 5 according to the flow velocity sensing result to stabilize the inlet flow velocity of the working section at 1m / s. Select a 602D11 vibration acceleration sensor and install it on the wall area above the horizontal plane of the circulating water tank 1. Record the background vibration and background noise of the circulating water tank 1 at this time, and measure three times.

[0074] 3) Adjust the flow rate using the steps described in step two, and measure the background vibration and noise of the circulating water tank at different flow rates;

[0075] 4) Turn off the thruster 5 and the signal acquisition device 16, lock the truss pulley 15, use the crane 32 to lift the installation platform 46 to a certain height, install the test model 45 at the bottom of the universal joint 44, and install test instruments such as pressure sensors and acceleration sensors inside the model. After installation, start the crane 32 to place the installation platform 46 above the slider 13 at the top of the circulating water tank 1, and fix the installation platform 46 with bolts.

[0076] 5) Turn on the signal acquisition device 16 to acquire signals from the pressure sensor, acceleration sensor, flow velocity sensor and hydrophone. Zero the device before measurement, start the thruster 5, acquire the initial flow velocity of the working section, and record the pressure, vibration acceleration and radiated noise of the test model after the flow velocity signal acquired by the flow velocity sensor 11 stabilizes. Each flow velocity is measured three times.

[0077] 6) Turn off the propeller 5 in the circulating water tank, use the crane 32 to hoist the test model 45 to a certain height, open the universal joint 44, start the drive motor 41, and raise the lifting rod 43 at the front end of the test model 45 through the lifting transmission mechanism 42 so that the test model 45 is at a 5° angle of attack with the horizontal plane. Lock the universal joint 44, reinstall and fix the model, and measure the vibration and sound radiation characteristics of the test model 45 at a 5° angle of attack. Measure three times.

[0078] 7) Remove the test model 45 and all kinds of sensors, turn off the thruster 5 and signal acquisition device 16 in the circulating water tank, and drain the water in the reverberation tank 2 and the circulating water tank 1.

[0079] Figure 6 A schematic diagram showing the measurement results of surface pulsating pressure and noise of the test model under different flow rates; Figure 7 The above two figures illustrate the measurement results of vibration acceleration and noise of the test model under different flow rates. They demonstrate that the flow-induced vibration and noise test device based on the circulating water tank of this application can simultaneously measure data such as pulsating pressure, vibration acceleration and noise in the same measurement. Multiple data can be obtained in a single measurement, making the measurement convenient and reliable.

[0080] The embodiments of the present invention disclosed above are merely illustrative of the invention. These embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the present invention, thereby enabling those skilled in the art to better understand and utilize the present invention.

Claims

1. A flow-induced vibration noise testing device based on a circulating water tank, characterized in that: It includes a reverberation water tank (2), a circulating water tank (1), a model hoisting device (3), a model angle of attack adjustment device (4), and a signal acquisition device (16); The circulating water tank (1) has a U-shaped structure. The circulating water tank (1) includes a working section, a first rectification section, a power section, a second rectification section and a third rectification section arranged in sequence and connected to each other. A rectification grid is provided in the rectification section to adjust the flow direction of the fluid in the circulating water tank (1). A propeller is provided in the power section. The working section of the circulating water tank (1) is a straight section and is located at the upper end of the reverberation tank (2). An observation window (10) is provided on the working section. A flow velocity sensing sensor (11) is installed on the wall at the starting position of the working section. An underwater camera is provided in the reverberation tank (2) to photograph the flow field characteristics around the test model (45) through the observation window (10) on the circulating water tank (1). The model hoisting device (3) includes two trusses (31), two cranes (32) and two installation platforms (46). The two trusses (31) are arranged facing each other. Truss pulleys (15) are installed at the bottom of the trusses (31). Two support plates are symmetrically arranged on both sides of the working section of the circulating water tank (1). Crane rails (9) that cooperate with the truss pulleys (15) at the bottom of the trusses (31) are provided on the support plates. The trusses (31) move on the crane rails (9) through the truss pulleys (15). The top of each truss (31) is connected to a crane (32) through the rail. The crane (32) is connected to the corresponding installation platform (46) through the hook. Two circulating water tank slide rails (12) are arranged opposite each other at the upper end of the working section of the circulating water tank (1). The bottom of the mounting platform (46) is engaged with the circulating water tank slide rails (12) through a slider (13). The model angle of attack adjustment device (4) includes two electric lifting mechanisms, two universal joints (44) and two connecting pipes. One electric lifting mechanism is arranged on each mounting platform (46). The output end of the electric lifting mechanism passes through the corresponding mounting platform (46) and is connected to a universal joint (44). The test model (45) is connected to the two universal joints (44) through the two connecting pipes. The overall position and angle of attack of the model can be freely adjusted through the truss, mounting platform, lifting rod and universal joint. The signal acquisition device (16) includes a command sending unit, a signal acquisition unit and a data storage unit. The command sending unit is connected to the signal acquisition unit through a signal transmission line. The signal acquisition unit is connected to the data storage unit through a signal transmission line. The signal acquisition unit includes a pressure sensor, an acceleration sensor, a strain gauge and a hydrophone. The hydrophone is installed in the reverberation tank (2). The pressure sensor, acceleration sensor and strain gauge are all installed inside the test model (45).

2. The flow-induced vibration noise testing device based on a circulating water tank according to claim 1, characterized in that: The reverberation water tank (2) includes a tank body, with an inlet at the top and a drain at the bottom. Sound-absorbing wedges (8) are distributed on the inner wall of the tank body, and a notch is provided at the top of the tank body to support the working section of the circulating water tank (1).

3. The flow-induced vibration noise testing device based on a circulating water tank according to claim 1, characterized in that: The propeller of the circulating water tank (1) is mounted on the wall of the circulating water tank (1) through bearings, and a drive motor (41) is installed on the outside. The first rectification section and the third rectification section are annular sections, and the second rectification section is a straight section. The rectification grid includes a flat guide plate (6) and an annular guide plate (7). The flat guide plate (6) is arranged in the second rectification section, and the annular guide plate (7) is arranged in both the first rectification section and the third rectification section.

4. The flow-induced vibration noise testing device based on a circulating water tank according to claim 1, characterized in that: The electric lifting mechanism includes a drive motor (41), a lifting transmission assembly (42), and a lifting rod (43). The drive motor (41) is connected to the mounting platform (46) by bolts. The output end of the drive motor (41) is connected to the lead screw in the lifting transmission assembly (42) through a turbine. A lead screw is fitted with a lead screw nut, and the lifting rod (43) is installed on the lead screw nut. The lower end of the lifting rod (43) passes through the mounting platform (46) and is connected to the test model (45) through a universal joint (44). The lifting transmission assembly (42) also includes a guide for the up and down movement of the lead screw nut.

5. The flow-induced vibration noise testing device based on a circulating water tank according to claim 4, characterized in that: The universal joint (44) can perform six degrees of freedom of motion. When measuring the fixed angle of attack, the two universal joints (44) at the front and rear of the test model (45) are locked to fix the model in the specified position. When it is necessary to adjust the angle of attack, the two universal joints (44) at the front and rear of the model are opened, and the length of the lifting rod (43) is adjusted by the electric lifting mechanism located at the head of the test model (45) to adjust the test model (45) to the specified angle of attack and lock the universal joint (44) to fix the position of the test model (45).

6. The flow-induced vibration noise testing device based on a circulating water tank according to claim 4, characterized in that: The upper end of the universal joint (44) is connected to the lifting rod (43) by a thread, and the lower end of the universal joint (44) is provided with a slot. The connecting pipe above the model is provided with a protrusion, and the test model (45) is fixed by the cooperation of the protrusion and the slot.

7. The flow-induced vibration noise testing device based on a circulating water tank according to claim 1, characterized in that: A vibration isolation pad (14) is provided between the circulating water tank slide rail (12) and the installation platform (46), and a vibration isolation pad (14) is also provided between the circulating water tank (1) and the reverberation water tank (2).

8. The flow-induced vibration noise testing device based on a circulating water tank according to claim 1, characterized in that: A sound insulation plate is installed on the outer wall of the power section of the circulating water tank (1).

9. The flow-induced vibration noise testing device based on a circulating water tank according to claim 1, characterized in that: The observation window (10) is installed in the middle area of ​​the working section by bolts and glass glue.

10. A test method for a flow-induced vibration noise testing device based on a circulating water tank according to any one of claims 1-9, characterized in that: Specifically, the following steps are included: Step 1: Fill the circulating water tank (1) and the reverberation water tank (2) with still water; Step 2: Turn on the drive motor of the propeller, start the signal acquisition device (16), and record the background vibration and background noise of the circulating water tank (1) at different flow rates. After measuring the flow rate three times for each group, turn off the drive motor of the propeller and the signal acquisition device (16). Step 3: Adjust the position of the crane on the slide rail according to the size of the test model (45), install the test model (45) below the lifting rod (43), lift the installation platform (46) to the designated position by the crane and fix it with bolts, and lock the universal joint (44); Step 4: Turn on the drive motor of the thruster again, start the signal acquisition device (16), wait for the value of the flow velocity sensor (11) to stabilize, record the sampling signals of the flow velocity sensor, pressure sensor, acceleration sensor and hydrophone, and turn off the drive motor of the thruster and the signal acquisition device (16) again after measuring the same flow velocity three times. Step 5: Adjust the angle of attack of the test model (45) by using the universal joint (44) and the lifting rod (43), and repeat Step 3 and Step 4 3 times to complete the experimental measurement under different angles of attack; Step 6: Remove the test model (45) and sensors, turn off the drive motor of the thruster and the signal acquisition device (16), and drain the water from the reverberation tank (2) and the circulating water tank (1).

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