A test device for acoustic radiation vibration of submersible structures in deep-sea environments

Abstract

The purpose of this invention is to provide a testing device for the acoustic radiation vibration of a submersible structure in a deep-diving environment. The device includes a deep-diving environment acoustic and vibration simulation chamber, a submersible structural assembly, and an acoustic and vibration signal testing system. The submersible structural assembly is suspended in the deep-diving environment acoustic and vibration simulation chamber via hinge hooks. The deep-diving environment acoustic and vibration simulation chamber is equipped with a pressure control valve, a pressure gauge, a first acoustic and vibration simulation chamber bus outlet, a second acoustic and vibration simulation chamber bus outlet, a first drain outlet, a second drain outlet, and a sealed outlet for hydrophone cables. The submersible structural assembly is equipped with a first excitation device, a second excitation device, and a vibration acceleration sensor. This invention is placed on a horizontal surface, and damping and vibration-reducing materials are applied to the inner walls and base of the acoustic and vibration simulation chamber, respectively, enabling the simulation of a deep-diving environment unaffected by ocean current waveguide effects, thereby ensuring the quality of the testing process.

Description

Technical Field

[0001] The present invention relates to a vibration testing device, specifically a submersible vibration acoustic radiation testing device. Background Technology

[0002] Existing submersible structural vibration and acoustic radiation testing equipment typically conducts experiments under shallow water pressure or measures vibration and acoustic radiation under atmospheric pressure. Changes in depth significantly impact the mechanical and vibratory acoustic properties of mechanical equipment. Most current research on submersible radiated noise is based on constant sound velocity and conventional vibration and acoustic radiation analysis, with limited research on the impact of parameter changes at greater depths on the vibration and noise generation of mechanical equipment. Studying the acoustic radiation patterns at greater depths and identifying relevant characteristics is crucial for designing targeted noise reduction schemes based on these patterns and differences to meet specific acoustic performance requirements. Therefore, simulating the environment at greater depths, accurately measuring the vibration and acoustic radiation of submersible structures, and discovering its patterns have become the main focus of current submersible research in this environment.

[0003] Previous predictions of acoustic radiation from submersible structural vibration tests mainly fell into the following two categories:

[0004] (1) Test device for acoustic radiation of structural vibration in shallow water environment.

[0005] This method utilizes free shallow water as the testing environment. Through sealed cables, underwater sensors, and other devices, it tests the acoustic radiation of submersible structural vibrations under different excitation conditions to derive the vibration transmission law of the submersible structure. This method can predict and measure the acoustic radiation of submersible structural vibrations in specific underwater environments. However, its drawbacks include the inability to fully simulate the high-pressure underwater environment at great depths, and the inability to fully consider the impact of depth changes on the submersible's mechanical and vibroacoustic properties. Furthermore, because the testing environment is a non-enclosed shallow water area, the underwater acoustic radiation signal is affected by the shallow-water waveguide effect, which also influences the obtained signal data.

[0006] (2) Underwater vibration and acoustic radiation measurement device at specific depths

[0007] This method is based on the propagation law of spherical waves in a free field. This testing method is difficult to implement because the waters surrounding my country are shallow continental shelves, affected by the shallow-water waveguide effect, and the testing process is significantly affected by marine environmental noise, resulting in large measurement errors. This method relies on a specific dock as the testing environment. At a specific depth, the instruments and equipment are calibrated by adjusting the attitude of vibration sensors and hydrophone arrays. After ensuring the stability of the testing equipment, the equipment inside the submersible structure is stabilized. Acceleration signals from the vibration sensors and acoustic signals from the hydrophone array are collected, and the resulting data is then processed by a computer. This method can accurately measure the vibration and sound radiation of a submersible structure in a specific dock. However, its drawbacks include the severe limitations of the testing site, the difficulty in setting up the site, and the inability to simulate deep-diving environments. Summary of the Invention

[0008] The purpose of this invention is to provide a test device for the vibration and acoustic radiation of a submersible structure in a deep-sea environment, which can simulate the deep-sea environment to the greatest extent and accurately measure the vibration and acoustic radiation characteristics under different working conditions.

[0009] The objective of this invention is achieved as follows:

[0010] This invention discloses a device for testing the acoustic radiation of submersible structures in deep-diving environments. The device comprises a deep-diving environment acoustic simulation chamber, a submersible structural device, and an acoustic signal testing system. The submersible structural device has a hinge hook and a bus outlet installed on its outer shell. The submersible structural device is suspended in the deep-diving environment acoustic simulation chamber via the hinge hook. The deep-diving environment acoustic simulation chamber is equipped with a pressure control valve, a pressure gauge, a first acoustic simulation chamber bus outlet, a second acoustic simulation chamber bus outlet, a first drain outlet, a second drain outlet, and a sealed outlet for hydrophone cables. The submersible structural device contains a first excitation device, a second excitation device, and a vibration acceleration sensor. The bus of the first excitation device, the second excitation device, and the vibration acceleration sensor extends from the submersible structural device bus outlet and connects to the first and second acoustic simulation chamber bus outlets, thereby connecting to the acoustic signal testing system. Hydrophones are arranged in the deep-diving environment acoustic simulation chamber, and the hydrophone cables extend through the sealed outlet and connect to the acoustic signal testing system.

[0011] The present invention may also include:

[0012] 1. The deep-sea environment acoustic and vibration simulation chamber includes a chamber body and a cover. The cover is connected to the chamber body through a flange and sealed to form a capsule-shaped structure. The inner wall of the chamber body is provided with damping material.

[0013] 2. The bottom of the deep-sea environment acoustic vibration simulation chamber is fixed to the horizontal ground using a steel frame support structure.

[0014] 3. The submersible structure is equipped with a first excitation device base and a second excitation device base. The first excitation device is installed on the first excitation device base, and the second excitation device is installed on the second excitation device base. The inner wall of the submersible structure is provided with a ring rib reinforcement structure. Vibration acceleration sensors are installed on the shell, the ring rib reinforcement structure, the first excitation device base, and the second excitation device base of the submersible structure.

[0015] 4. Seawater is added to the deep-sea environment acoustic vibration simulation chamber through the first and second drainage outlets, and compressed air is added to the deep-sea environment acoustic vibration simulation chamber through the pressure control valve to maintain the high-pressure environment at deep depth.

[0016] The advantages of this invention are as follows: This invention employs a pressure control valve to regulate the pressure within the acoustic-vibration simulation chamber, thereby altering the deep-sea environment in which the submersible's structural components operate. After the excitation equipment stabilizes, a frequency converter and signal generator can be used to simulate the actual operating conditions of a submersible. By scaling down the submersible's structural components using technical means, the invention reduces labor and resource waste while simulating the actual submersible structure. Multiple sealing methods are used to seal the entire experimental device, ensuring stable pressure within the device during testing and thus preventing the simulated deep-sea environment from being affected. Placing the entire testing device on a level surface, and applying damping and vibration-damping materials to the inner walls and base of the acoustic-vibration simulation chamber, respectively, simulates a deep-sea environment unaffected by ocean current waveguide effects, thereby ensuring the quality of the testing process. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the operation process of the present invention;

[0018] Figure 2 This is the main view of the acoustic vibration simulation chamber;

[0019] Figure 3 Side view of the acoustic vibration simulation chamber;

[0020] Figure 4 This is a front view of the submersible's structural components;

[0021] Figure 5 This is a cross-sectional view of the submersible's structural components;

[0022] Figure 6 A schematic diagram showing the assembly of the acoustic vibration simulation chamber and the submersible's structural components;

[0023] Figure 7 This is a schematic diagram showing the connection between the acoustic and vibration signal testing system and the testing device. Detailed Implementation

[0024] The invention will now be described in more detail with reference to the accompanying drawings:

[0025] Combination Figure 1-7 The present invention relates to a submersible structural vibration and acoustic radiation testing device for deep-diving environments, comprising a submersible structural device, a deep-diving environment acoustic and vibration simulation chamber, and an acoustic and vibration signal testing system. The submersible structural device includes excitation devices 14 and 15, excitation device bases 13 and 16, and a vibration acceleration sensor 18. The bus of the excitation devices 14 and 15 and the vibration acceleration sensor 18 extends from the bus outlet 12 of the submersible structural device, and connects to the bus outlets 3 and 5 of the acoustic and vibration simulation chamber via high-pressure sealed pipes, and is then connected to the acoustic and vibration signal testing system. After the internal devices of the submersible structure are installed and the bus is connected, it is suspended in the deep-diving environment acoustic and vibration simulation chamber via hinge hooks 11. A hydrophone 19 is arranged in the acoustic and vibration simulation chamber, and its cable extends through the hydrophone cable sealing hole 8 and connects to the acoustic and vibration signal system. After adjusting the test attitude of the hydrophone 19, the excitation devices 14 and 15 are operated and kept stable. The chamber cover 1 of the acoustic and vibration simulation chamber is assembled to the chamber body through the flange bolt assembly holes 10 for sealing. After the acoustic and vibration simulation chamber is sealed, check whether the chamber cover 1, pressure control valve 2, pressure gauge 4, hydrophone cable sealing hole 8, and drain outlets 7 and 9 are sealed. Introduce compressed air into the acoustic and vibration simulation chamber through pressure control valve 2 for pressure testing. Once the internal pressure reaches the specified value and no structural damage or depressurization is observed, the pressure inside the submersible's structural components is the same as atmospheric pressure, and a high-pressure environment exists between the submersible's structural components and the acoustic and vibration simulation chamber. Depressurize through drain outlets 7 and 9, and then check the seal. Add seawater through drain outlets 7 and 9. After adding water, add compressed air through pressure control valve 2, observing the pressure gauge reading during pressurization. After pressurization, check the overall sealing of the acoustic and vibration simulation chamber and set the designated pressure through pressure control valve 2 to maintain a high-pressure environment at great depths.

[0026] Check that the wiring connections of the acoustic and vibration signal testing system are secure, and confirm that the power supply is grounded and turned on. Start the relevant equipment of the excitation system, turning on the frequency converter, power amplifier, and signal generator to ensure that the excitation equipment is operating normally. Start the relevant equipment of the testing system, including the data acquisition instrument, charge amplifier, and computer. The computer processes the sensor signals received by the data acquisition instrument and generates corresponding images on the computer testing software. The images and the operating status of the equipment are used to determine whether the entire testing system is operating normally. After confirming that the acoustic and vibration signal testing system is normal, adjust the frequency converter, power amplifier, and signal generator to control the operating conditions of the excitation equipment in the submersible structure under different conditions. Finally, collect and record the acoustic and vibration signals.

[0027] The technical problems to be solved by this invention include:

[0028] (1) Development of Submarine Structure and Devices

[0029] First, there is the issue of connecting the internal equipment and sensor bus of the submersible's structural components with the acoustic and vibration signal testing system; second, there is the issue of the scale ratio between the submersible's structural components and the actual submersible.

[0030] (2) Development of a Deep-Diving Environment Acoustic Vibration Simulation Chamber

[0031] First, the deep-sea environment simulation chamber is made of steel, resulting in significant mid-to-high frequency acoustic reverberation in the water. Second, to simulate the high-pressure environment of the deep sea, seawater and compressed air need to be injected into the acoustic simulation chamber to simulate the high-pressure state. The connection between the submersible's structural device bus outlet and the deep-sea environment acoustic simulation chamber bus interface, as well as the connection between the end caps of the acoustic simulation chamber and the main body of the chamber, requires consideration of the gas-liquid two-phase sealing problem.

[0032] (3) Application of excitation from the simulated submersible vibration source

[0033] First, how to simulate the excitation force of a real submersible's propulsion system within the submersible's structural components; second, how the excitation equipment can simulate real operating conditions and stably output the excitation force.

[0034] (4) Arrangement and measurement of vibration and acoustic radiation testing system

[0035] First, there's the issue of the circumferential directivity of the hydrophone probes placed in the acoustic vibration simulation chamber. Second, there's the issue of sealing during the connection process between the hydrophone cables inside the acoustic vibration simulation chamber and the external acoustic vibration signal testing system.

[0036] The technical solution adopted by the present invention to solve its technical problem includes:

[0037] (1) Development of Submarine Structure and Devices

[0038] The submersible structural device is connected to the deep-sea environment acoustic and vibration simulation chamber via a high-pressure sealed pipe. The internal excitation equipment of the submersible structural device is connected to the acoustic and vibration signal testing system via a bus. The bus outlet of the submersible structural device is connected to the acoustic and vibration simulation chamber via a high-pressure sealed pipe, and the interface is sealed to prevent high-pressure water vapor from entering. The submersible structural device is subjected to scale effect conversion using dimensional analysis and other empirical formulas to obtain the corresponding vibration performance. Based on the conversion results, the submersible structural device needs to satisfy geometric similarity, dynamic similarity, and kinematic similarity under various test conditions. On this basis, the dimensions of the submersible structural device are scaled down.

[0039] (2) Development of a Deep-Diving Environment Acoustic Vibration Simulation Chamber

[0040] The deep-diving environment acoustic and vibration simulation chamber is capsule-shaped and constructed with high-strength pressure vessel steel. The inner walls are lined with sound-absorbing and heat-insulating materials. The bottom of the chamber is connected to the ground via a steel frame support structure, with vibration isolation devices fixed to the ground. The entire experimental setup is placed on a level surface. After the submersible structure and testing equipment are placed inside the deep-diving environment simulation chamber, the bus outlets of the cables used for system installation and testing instruments are connected using flanges and sealed. To achieve sufficient sealing in the deep-diving environment, lead-based metal gaskets of the same diameter are applied at the junction of the chamber body and the hatch. Pneumatic wrenches are used to symmetrically tighten the flange bolts, ensuring that the preload of each bolt is the same and can withstand the internal pressure of the simulation chamber.

[0041] The ascent and descent of the submersible's structural device are regulated by pressure control valve 2; the pressure is reduced during ascent and increased during descent. The entire device is equipped with one pressure control valve 2, which automatically cuts off pressure when the internal pressure exceeds a predetermined limit. The arc at the front of the chamber serves as a pressure buffer front chamber 1, connecting the pressurization equipment to the main body of the chamber. The front chamber 1 forms a buffer zone, ensuring pressure stability in the experimental simulation chamber. The deep-diving environmental acoustic vibration simulation chamber is a steel structure; therefore, mid-to-high frequency acoustic reverberation in the water is relatively severe. To ensure near-free-field characteristics of sound field propagation, damping material is applied to the inner wall of the simulation chamber.

[0042] (3) Application of excitation from the simulated submersible vibration source

[0043] The dynamic excitation system is sealed and installed on the base of the submersible structure. A frequency converter and a signal generator are connected to the end of its bus to control the magnitude and form of the stable output excitation of the dynamic excitation system.

[0044] (4) Arrangement and measurement of vibration and acoustic radiation testing system

[0045] Vibration sensors 18 are arranged on the shell of the submersible structure, the ring rib reinforcement structure 17, the panel and web of the vibration excitation equipment base. Considering the circumferential directivity of the hydrophone, a hydrophone 19 is arranged in the acoustic vibration simulation chamber and its attitude is adjusted. The hydrophone cable inside the acoustic vibration simulation chamber is wrapped with a thermoplastic tube, and the hydrophone cable outlet on the acoustic vibration simulation chamber is sealed with a high-pressure sealing stuffing box of the corresponding diameter. The high-pressure sealing stuffing box is then assembled with the hydrophone cable sealing outlet on the simulation chamber body.

[0046] A high-pressure sealing pipe is used to connect the bus outlet of the submersible's structural components to the bus outlet of the deep-sea environment acoustic and vibration simulation chamber to ensure that the internal air pressure of the submersible's structural components is the same as the external atmospheric pressure. A polyethylene PTFE gasket is installed at the interface between the bus outlet and the high-pressure sealing pipe to resist the high pressure outside the pipe and achieve a seal.

Claims

1. A device for testing the structure-borne sound radiation of a submersible in a deep diving environment, characterized by: The deep diving environmental acoustic vibration simulation cabin comprises a deep diving environmental acoustic vibration simulation cabin, a submersible structure device, and an acoustic vibration signal test system. After adjusting the test posture of the hydrophone, the first excitation device and the second excitation device are operated and kept stable, compressed air is added into the acoustic vibration simulation cabin through the pressure control valve for pressure test, when the pressure in the cabin reaches the specified value and no structural damage and pressure loss problem occurs, the pressure inside the submersible structure device is the same as the atmospheric pressure, and the submersible structure device and the acoustic vibration simulation cabin are in a high-pressure state; the pressure is released through the first drain port and the second drain port, and the sealing is checked after completion; sea water is added through the first drain port and the second drain port, and after the water is added, compressed air is added through the pressure control valve, the pressure gauge reading is observed during the pressurization process, the sealing of the entire acoustic vibration simulation cabin is checked after the pressurization is completed, and the specified pressure is set through the pressure control valve to maintain the deep diving high-pressure environment.

2. The device according to claim 1, characterized in that: The deep diving environmental acoustic vibration simulation cabin comprises a cabin body and a cabin cover.

3. The device according to claim 1, characterized in that: The bottom of the deep diving environmental acoustic vibration simulation cabin is fixed to the horizontal ground by a steel frame support structure.

4. The device according to claim 1, characterized in that: The first excitation device base and the second excitation device base are arranged in the submersible structure device, the first excitation device is mounted on the first excitation device base, the second excitation device is mounted on the second excitation device base, the inner wall of the submersible structure device is provided with a ring rib reinforcing structure, and the vibration acceleration sensors are arranged on the shell, the ring rib reinforcing structure, the first excitation device base and the second excitation device base of the submersible structure device.

5. The device according to claim 1, characterized in that: Sea water is added into the deep diving environmental acoustic vibration simulation cabin through the first drain port and the second drain port, and compressed air is added into the deep diving environmental acoustic vibration simulation cabin through the pressure control valve to maintain the deep diving high-pressure environment.

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