Pneumatic vibration source for underwater sound generation

Abstract

The invention relates to the technical field of underwater acoustic equipment, and discloses a pneumatic seismic source for underwater acoustic subsound generation, which comprises a plurality of pneumatic seismic source units, part of the pneumatic seismic source units are main pneumatic seismic sources, the rest of the pneumatic seismic source units are auxiliary pneumatic seismic sources, and the number of the auxiliary pneumatic seismic sources is not less than that of the main pneumatic seismic sources. The auxiliary pneumatic seismic sources corresponding to the main pneumatic seismic sources are distributed around the main pneumatic seismic sources in an array mode, launching ports of the multiple pneumatic seismic source units all face the same direction, each pneumatic seismic source unit comprises an operation chamber and a launching chamber which are communicated in a one-way mode, and an air inlet of the operation chamber is connected with an external air source so that inert gas can be introduced into the operation chamber. The launching port is located at the end of the launching chamber away from the operation chamber. According to the invention, the emission time of each emission chamber can be respectively adjusted, the frequency range of infrasonic waves is widened, the intensity of the infrasonic waves can be increased, and broadband infrasonic signals with the intensity of more than 200dB can be generated in an underwater environment.

Description

Technical Field

[0001] The present invention relates to the technical field of underwater acoustic devices, and particularly to a pneumatic sound source for underwater infrasound generation. Background Art

[0002] Infrasound refers to sound waves with a frequency lower than 20 Hz, which can propagate over extremely long distances in seawater with little attenuation. Due to the special physical properties of infrasound, it has always been the focus of research by many scientists.

[0003] In the field of underwater acoustics, underwater sound source technology is one of the key technologies for underwater detection and communication. Current underwater infrasound sources are difficult to meet these multi-dimensional application requirements. When traditional electric infrasound generators are applied underwater, they face many technical bottlenecks. The underwater environment has extremely high requirements for the waterproof and pressure-resistant performance of electric devices. The complex sealing and pressure-resistant structures increase the volume and weight of the devices, which is not conducive to flexible underwater deployment and long-term stable operation. At the same time, the energy conversion efficiency of electric generators is limited by the physical process of converting electrical energy into mechanical energy, and it is difficult to achieve high-efficiency infrasound energy output. Especially when high-energy infrasound signals (such as above 200 dB) are required, it seems powerless. Moreover, the frequency range of the infrasound generated by it is relatively narrow, which is difficult to meet the requirements of broadband detection and research, and limits the comprehensive analysis of different-scale ocean phenomena.

[0004] As another means of infrasound generation, pneumatic sound sources have certain potential, but there are still obvious defects in the existing technologies. Most pneumatic sound sources lack flexibility in the regulation of infrasound frequency and often rely on simple gas path structures and mechanical devices, unable to achieve broadband coverage of infrasound frequency. For example, in a common single-chamber pneumatic sound source such as an air gun, its main components include an air chamber, a shuttle, and a firing valve. The air chamber is used to store high-pressure air, and the shuttle is used to control the release of air. When the air gun is triggered, the firing valve opens, and the high-pressure air quickly passes through the shuttle and is released into the water. The shuttle moves quickly under the action of the high-pressure air, forming a high-pressure shock wave, and the shock wave triggers the cavitation effect, thereby generating infrasound waves. This structure can only generate infrasound waves with specific frequencies or within a limited frequency range, and it is difficult to adapt to complex and changeable underwater acoustic research and application scenarios. In addition, in terms of the amplification and stable maintenance of infrasound energy, the existing pneumatic sound source technology is not mature enough to boost the infrasound wave energy to a relatively high level within a broadband and maintain stable output, resulting in limited detection distance and signal resolution in practical applications and unable to meet the requirements of tasks such as deep-sea long-distance detection and high-precision geological exploration. Summary of the Invention

[0005] To solve the above technical problems, the present invention provides a pneumatic sound source for underwater infrasound generation, which can stably output infrasound in a relatively wide frequency band range.

[0006] The present invention provides a pneumatic sound source for underwater infrasound generation, including a plurality of pneumatic sound source units, among which some pneumatic sound source units are main pneumatic sound sources, and the rest are auxiliary pneumatic sound sources. The number of auxiliary pneumatic sound sources is not less than that of the main pneumatic sound sources. The array of auxiliary pneumatic sound sources corresponding to each main pneumatic sound source is distributed around the main pneumatic sound source. The emission ports of the plurality of pneumatic sound source units all face the same direction. Each pneumatic sound source unit includes an operation chamber and an emission chamber that are unidirectionally connected. The air inlet of the operation chamber is connected to an external air source to introduce inert gas into the operation chamber. The emission port is located at the end of the emission chamber far from the operation chamber.

[0007] Optionally, the emission port of the main pneumatic sound source protrudes from the emission port of the auxiliary pneumatic sound source.

[0008] Optionally, the length of the emission chamber is 5m - 6m, the internal cavity of the emission chamber is cylindrical, and the radius of the internal cavity of the emission chamber is 250mm - 280mm.

[0009] Optionally, the length of the operation chamber is 1m - 2m, the internal cavity of the operation chamber is cylindrical, and the radius of the internal cavity of the operation chamber is equal to the radius of the internal cavity of the emission chamber.

[0010] Optionally, the part of the outer shell 8 of the pneumatic sound source unit where the emission port is located is arc-shaped.

[0011] Optionally, a channel is opened on the connecting wall between the operation chamber and the emission chamber, and a cup-shaped flange is connected to the channel.

[0012] Optionally, an air inlet valve is provided at the air inlet of the operation chamber. The air inlet valve is connected to an air inlet pipe, and the air inlet pipe is located inside the operation chamber. A check valve is provided at the air outlet of the operation chamber. The check valve is connected to a check pipe, and the check pipe is arranged parallel to the air inlet pipe inside the operation chamber.

[0013] Optionally, a flow control valve and a pressure balance valve are provided inside the operation chamber. The flow control valve is arranged on the gas passage in the cup-shaped flange. The air flow is modulated by the flow control valve and then enters the emission chamber through the cup-shaped flange. The pressure balance valve is connected to the air inlet of the operation chamber to make the air flow entering the operation chamber in a stable state. A pressure sensor and a temperature sensor are also provided inside the operation chamber, and a flow sensor is provided inside the emission chamber to monitor the gas flow inside the emission chamber.

[0014] Optionally, the array distribution includes one of the following: planar array, three-dimensional array, circular array, grid array, spiral array, and fractal array.

[0015] Optionally, a connecting member 109 is fixed on the outer wall of each pneumatic vibration source unit, and the main pneumatic vibration source and the corresponding secondary pneumatic vibration source are connected and fixed through the connecting member 109.

[0016] The technical solution provided by the embodiment of the present invention has the following advantages compared with the prior art: In the pneumatic vibration source for underwater infrasound generation provided by the embodiment of the present invention, high-pressure inert gas enters the operation chamber. Under the regulation of the operation chamber, the gas enters the emission chamber. When a trigger instruction is issued, the gas in the emission chamber is instantaneously released into the underwater environment through the emission port to form bubbles. Due to the cavitation effect, the bubbles generate sound waves. Since the vibration frequency of the bubbles is relatively low, infrasound-frequency sound waves are generated. By arranging the secondary pneumatic vibration source array around the main pneumatic vibration source, the emission time of each emission chamber can be adjusted respectively and infrasound waves of different frequency bands can be generated, thereby broadening the infrasound frequency band range. At the same time, the energies of the generated infrasound waves can be superimposed on each other. The infrasound waves emitted by the secondary pneumatic vibration source eliminate the ghost signals generated during the sound generation process of the main pneumatic vibration source, thereby effectively increasing the sound pressure level and also increasing the intensity of the infrasound waves. Since the gas instantaneously diffuses uniformly after entering the emission chamber, local energy concentration and pressure mutation are avoided, thereby optimizing the bubble formation process and the initial oscillation characteristics and enhancing the stability of infrasound wave generation. The pneumatic vibration source for underwater infrasound generation provided by the present invention can accurately generate infrasound signals with a wide frequency band and an intensity of more than 200 dB in an underwater environment. The overall structural design fully considers the special requirements of underwater operations, has a simple structure, high environmental adaptability and is easy to operate. It can set and flexibly adjust the infrasound frequency to meet the requirements for infrasound signals of specific frequencies in different application scenarios. Description of the Drawings

[0017] Figure 1 It is a schematic internal structure diagram of a pneumatic vibration source for underwater infrasound generation provided by an embodiment of the present invention; Figure 2 It is a schematic structural diagram of a single pneumatic vibration source unit provided by an embodiment of the present invention; Figure 3 It is an array structure schematic diagram provided by an embodiment of the present invention.

[0018] Description of the reference numerals: 101, intake valve; 102, intake pipe; 103, check valve; 104, check pipe; 105, operation chamber; 106, cup-shaped flange; 107, emission chamber; 108, outer shell; 109, connecting member. Detailed Embodiments

[0019] The following combines the drawings to describe in detail a specific embodiment of the present invention, but it should be understood that the protection scope of the present invention is not limited by the specific embodiment.

[0020] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the technical solutions of the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0021] The current infrasonic wave generating structure can only generate infrasonic waves of specific frequencies or within a limited frequency range, making it difficult to adapt to complex and changing underwater acoustic research and application scenarios. In addition, in terms of the amplification and stable maintenance of infrasonic energy, the existing pneumatic source technology is not mature enough to boost the infrasonic energy to a relatively high level within a wide frequency band and maintain stable output, resulting in limited detection range and signal resolution in practical applications and being unable to meet the requirements of tasks such as deep-sea long-distance detection and high-precision geological exploration.

[0022] Therefore, an embodiment of the present invention provides a pneumatic source for underwater infrasonic wave generation, which can stably output infrasonic waves within a relatively wide frequency band range.

[0023] At least one embodiment of the present invention provides a pneumatic source for underwater infrasonic wave generation, including a plurality of pneumatic source units, among which some pneumatic source units are main pneumatic sources, and the rest are auxiliary pneumatic sources. The number of auxiliary pneumatic sources is not less than that of the main pneumatic sources. The auxiliary pneumatic source arrays corresponding to each main pneumatic source are distributed around the main pneumatic source. The emission ports of the plurality of pneumatic source units all face the same direction. Each pneumatic source unit includes an operation chamber and an emission chamber that are unidirectionally connected. The air inlet of the operation chamber is connected to an external air source to introduce inert gas into the operation chamber, and the emission port is located at the end of the emission chamber far from the operation chamber.

[0024] In the pneumatic source for underwater infrasonic wave generation provided by the above embodiment of the present invention, by arranging the auxiliary pneumatic source arrays around the main pneumatic source, the emission time of each emission chamber can be adjusted respectively and infrasonic waves of different frequency bands can be generated. Thus, while broadening the frequency band range of the infrasonic waves, the infrasonic waves emitted by the auxiliary pneumatic sources can eliminate the ghost signals generated during the sound generation process of the main pneumatic source and can also increase the intensity of the infrasonic waves.

[0025] The present invention will be described below through several specific embodiments. To keep the description clear and concise for the following embodiments of the present invention, the detailed description of known functions and known components may be omitted. When any component of the embodiments of the present invention appears in more than one drawing, the component may be represented by the same reference numeral in each drawing.

[0026] Reference Figure 1 and Figure 2 , Figure 1 FIG. is a schematic internal structure diagram of a pneumatic sound source for underwater infrasound generation provided by an embodiment of the present invention, Figure 2 is a schematic structural diagram of a single pneumatic sound source unit provided by an embodiment of the present invention. As shown in Figure 1 and Figure 2 shown, an embodiment of the present invention provides a pneumatic sound source for underwater infrasound generation, which includes a plurality of pneumatic sound source units 1, where some of the pneumatic sound source units 1 are main pneumatic sound sources, and the rest are auxiliary pneumatic sound sources. The number of auxiliary pneumatic sound sources is not less than that of the main pneumatic sound sources. The auxiliary pneumatic sound source arrays corresponding to each main pneumatic sound source are distributed around the main pneumatic sound source. The emission ports of the plurality of pneumatic sound source units 1 all face the same direction, so that the infrasound waves emitted by the auxiliary pneumatic sound sources eliminate the ghost signals generated during the sound generation process of the main pneumatic sound source. Each pneumatic sound source unit 1 includes an operation chamber 105 and an emission chamber 107 that are unidirectionally connected. The air inlet of the operation chamber 105 is connected to an external air source to introduce inert gas into the operation chamber 105. The external high-pressure air source is inert gas. Inert gas is not easily chemically reacted with the medium, which can ensure that the inside of the device is not corroded. The external high-pressure air source is connected to the operation chamber 105 through an underwater air pipe, so as to introduce inert gas into the device. The emission port is located at the end of the emission chamber 107 away from the operation chamber 105. The emission chamber 107 is made of high-strength stainless steel material, and its inner wall is precisely processed and polished, so its surface roughness is very low, which can reduce gas flow resistance and turbulent flow phenomenon, and improve energy conversion efficiency.

[0027] In the pneumatic sound source for underwater infrasound generation provided by an embodiment of the present invention, high-pressure inert gas enters the operation chamber. Under the regulation of the operation chamber, the gas enters the emission chamber. When a trigger command is issued, the gas in the emission chamber is instantaneously released into the underwater environment through the emission port to form bubbles. Due to the cavitation effect, the bubbles generate sound waves. Since the vibration frequency of the bubbles is relatively low, infrasound frequency band sound waves are generated. By arranging the auxiliary pneumatic sound source arrays around the main pneumatic sound source, the emission time of each emission chamber can be adjusted respectively and infrasound waves of different frequency bands can be generated, so as to broaden the infrasound frequency band range. At the same time, the energy of the generated infrasound waves can be superimposed on each other. The infrasound waves emitted by the auxiliary pneumatic sound sources eliminate the ghost signals generated during the sound generation process of the main pneumatic sound source, thereby effectively increasing the sound pressure level and also increasing the intensity of the infrasound waves. Since the gas instantaneously diffuses evenly after entering the emission chamber, local energy concentration and pressure mutation are avoided, thereby optimizing the bubble formation process and the initial oscillation characteristics, and improving the stability of infrasound wave generation. The overall structural design fully considers the special requirements of underwater operations, has a simple structure, high environmental adaptability and is easy to operate. It can set and flexibly adjust the infrasound frequency to meet the requirements for specific frequency infrasound signals in different application scenarios.

[0028] Reference Figure 3 , Figure 3 is a schematic diagram of the array structure provided by the embodiment of the present invention. As Figure 3 shown, the emission port of the main pneumatic source protrudes from the emission port of the secondary pneumatic source. The advantage of this design is that the secondary pneumatic source can be started during the operation of the main pneumatic source, rather than waiting for the main source to end, thereby reducing the overall working cycle of the device.

[0029] In the embodiment of the present invention, the length of the emission chamber 107 is 5m - 6m, the internal cavity of the emission chamber 107 is cylindrical, and the radius of the internal cavity of the emission chamber 107 is 250mm - 280mm. In a traditional pneumatic source, when the baffle is quickly opened, air will be quickly released, forming a high-pressure shock wave. This rapid release will generate high-frequency sound waves in a short time because high-frequency signals are usually related to rapid pressure changes. The existence of the acceleration distance causes the air to be released in a short time, resulting in the generation of high-frequency energy. Compared with a traditional air gun with a diameter of about 100mm and a length of about 0.5m, the pneumatic source in the embodiment of the present invention has a larger volume. The longer emission chamber 107 can lengthen the signal rise time, eliminate the acceleration distance, and slow down the speed of air release, which means that the air release process is smoother and the pressure change is slower, thereby reducing the generation of high-frequency energy. This design produces a longer bubble period, which can effectively increase the low-frequency signal, making the signal of the pneumatic source more concentrated in the low-frequency band instead of generating a large amount of high-frequency noise, and at the same time optimizing the quality of the infrasound wave.

[0030] Specifically, the length of the operation chamber 105 is 1m - 2m, the internal cavity of the operation chamber 105 is cylindrical, and the radius of the internal cavity of the operation chamber 105 is equal to the radius of the internal cavity of the emission chamber 107.

[0031] Optionally, the part of the outer shell 108 of the pneumatic source unit 1 where the emission port is located is arc-shaped. The top of the arc-shaped part has the effect of accelerating the air flow. The entire outer shell 108 is cylindrical, and this shape is the best in the underwater environment. The outer shell 108 is made of high-strength stainless steel material. The material of the outer shell 108 is specially selected and anti-corrosion treated, and can resist a certain water pressure and seawater corrosion.

[0032] Furthermore, a channel is opened on the connecting wall between the operation chamber 105 and the emission chamber 107, and a cup-shaped flange 106 is connected to the channel. The operation chamber 105 and the emission chamber 107 are separated from each other and are connected by the cup-shaped flange 106. The cup-shaped flange 106 can withstand a large pressure, maintain the overall stability, and also play a role in smoothing the air flow. The cup-shaped flange 106 is made of high-strength titanium alloy, so it can withstand high pressure and air flow impact. The sealing surface of the cup-shaped flange 106 uses a special rubber sealing material, which can effectively prevent gas leakage. The operation chamber 105 and the emission chamber 107 are connected through the cup-shaped flange 106 and the extension port. During the connection process, appropriate fastening bolts are evenly tightened to ensure the firmness of the connection and good sealing, so that gas can flow smoothly between the two. After the gas comes out through the cup-shaped flange 106 and the channel, it enters the emission chamber 107. The extension port is nearly 360°, which can realize gas exchange between the operation chamber 105 and the emission chamber 107 in a larger range, greatly increasing the gas exchange efficiency between the emission chamber 107 and the operation chamber 105. After the gas enters the emission chamber 107, it instantaneously diffuses evenly, avoiding local energy concentration and pressure mutation, thereby optimizing the bubble formation process and the initial oscillation characteristics, enhancing the stability of the generation of infrasound waves, and strengthening the low-frequency signal emission ability and the overall broadband performance of the device.

[0033] In this embodiment, an intake valve 101 is provided at the intake port of the operation chamber 105. The intake valve 101 is connected to an intake pipe 102. The intake pipe 102 is located inside the operation chamber 105. A check valve 103 is provided at the outlet of the operation chamber 105. The check valve 103 is connected to a check pipe 104. The check pipe 104 is arranged parallel to the intake pipe 102 inside the operation chamber 105. The addition of the intake pipe 102 can play a role in smoothing the input air flow, which is beneficial to improving the reliability and controllability of the device. The function of the check pipe 104 is to serve as an air flow path for balancing air pressure. When the gas pressure inside the operation chamber 105 is too high, it can flow out through the check pipe 104.

[0034] An air-driven sound source for underwater infrasound generation according to an embodiment of the present invention is provided with an air inlet at the tail. The opening is sealed. When an external high-pressure gas source is connected to the intake valve 101 through an underwater air pipe, the air inlet opening can be opened. The opening is strictly sealed from the outside to ensure that external water flow does not enter the device. The external high-pressure gas source is an inert gas and is connected to the intake valve 101 through an underwater pipe. At the same time, the gas enters the operation chamber 105 through the intake pipe 102. The intake valve 101 and the intake pipe 102 are located in the upper part of the operation chamber 105. In addition, the check valve 103 and the check pipe 104 are also located in the upper part of the operation chamber 105. The intake pipe 102, the check pipe 104, the operation chamber 105, and the emission chamber 107 form the entire air flow channel. The inner walls of the entire internal chamber and the inner walls of each pipe are designed to be streamlined, with smooth inner walls and gradually changing pipe diameters, which are gradually optimized in the direction from the intake end to the emission chamber 107 to ensure smooth gas flow inside the device, reduce energy loss and turbulence phenomena. The intake valve 101 has high-precision flow regulation ability and can accurately control the flow rate of the inert gas entering the intake pipe 102 according to different working conditions. The diameter of the intake pipe 102 can be 50 mm, which is made of titanium alloy material, has high strength and corrosion resistance, can withstand the pressure of external high-pressure gas, and its inner part is smooth and streamlined, which can greatly reduce gas flow resistance and turbulence phenomena, and ensure the smooth entry of high-pressure gas into the operation chamber 105. The diameter of the check pipe 103 is 30 mm, and its inner wall is also streamlined. The check valve 103 and the check pipe 104 work together to ensure the unidirectional flow of gas in the operation chamber 105, strictly prevent gas backflow, avoid equipment failures, energy losses and potential safety hazards caused by backflow, and ensure the continuity and stability of the sound source emission process. The operation chamber 105 is made of titanium alloy material, and the intake valve 101, the intake pipe 102, and the operation chamber 105 are integrally connected, so the airtightness inside can be ensured.

[0035] Reference Figure 1, a flow control valve and a pressure balance valve are arranged in the operation chamber 105. The flow control valve is arranged on the gas passage in the cup-shaped flange 106. The gas flow is modulated by the flow control valve and enters the launch chamber 107 through the cup-shaped flange 106. The pressure balance valve is connected to the air inlet of the operation chamber 105 so that the gas flow entering the operation chamber 105 is in a stable state. A pressure sensor and a temperature sensor are also arranged in the operation chamber 105. A flow sensor is also arranged in the launch chamber 107 to monitor the gas flow in the launch chamber 107. The flow control valve can accurately match the required gas volume according to different infrasound generation requirements, and the pressure balance valve maintains the gas pressure in the operation chamber 107 stable. The pressure sensor can monitor the gas pressure in the operation chamber 105 in real time to ensure that the gas entering the launch chamber 107 reaches the expected pressure value and is within the efficient working range. The temperature sensor determines whether the entire device is overheated by monitoring the temperature of the operation chamber 105, thereby ensuring the normal operation of the device. Under the regulation of the overall system, each valve and sensor ensures that the gas parameters in the launch chamber 107 reach the required parameters. When the control valve is opened, high-pressure gas will be emitted instantly. The pressure sensor can monitor the pressure of the gas in the emission chamber 107. When the gas pressure is lower than the target pressure, the system will control the intake valve 101 and the valve in the operating chamber 105 to respond accordingly.

[0036] Optionally, the array distribution includes: a plane array, a three-dimensional array, a ring array, a grid array, a spiral array, and a type array. Figure 3 The figure shows a situation where there is an auxiliary pneumatic source in each array on both sides of a main pneumatic source. Three pneumatic source units 1 form a linear array source. After the infrasound waves are emitted from the emission ports at different positions, their wavefronts will interact in a specific way in space to achieve the optimization of the spatial distribution of the sound wave energy. The array design allows the spacing and layout of each emission unit to be flexibly adjusted according to the underwater acoustic environment. The emission time and emission airflow pressure of different emission units are adjusted by the overall system to achieve the optimization of the spatial distribution of the sound wave energy and the complementation of the frequency characteristics. For example, for a linear array composed of 6 sources, to achieve 15Hz In order to complement the characteristics within the frequency range of -30Hz, the six seismic sources are divided into three groups, each group has two seismic sources, one of which is the main pneumatic seismic source and the other is the auxiliary pneumatic seismic source. The excitation signals of the first group of seismic sources mainly contain frequency components of 15Hz-20Hz, the second group mainly contains frequency components of 20Hz-25Hz, and the third group contains frequency components of 25Hz-30Hz. By controlling the frequency and amplitude of the excitation signals of each seismic source, the infrasound waves emitted by them are superimposed on each other in space, thereby achieving smooth response and energy enhancement in the entire frequency range of 15Hz-30Hz, and achieving the purpose of complementary frequency characteristics.

[0037] Specifically, a connecting member 109 is fixed on the outer wall of each pneumatic vibration source unit 1, and the main pneumatic vibration source and the corresponding secondary pneumatic vibration source are connected and fixed through the connecting member 109. Two hook devices are provided on the outer shell 108, and the distance between the two hooks is 800 mm (along the axial direction, in Figure 2 visible), and the hooks can provide connection points during underwater positioning and deployment to ensure that there is no displacement due to water flow impact.

[0038] An array installation position is also provided on the outer shell 108 of the present invention. A connecting member 109, such as a hook, is provided at the array installation position. Bolts are used to connect the outer shells 108 of different pneumatic vibration source units 1 to the bracket. The brackets are connected through hooks to achieve pairwise combination. The brackets are designed according to different array requirements, and different array methods, the relative positions and spacings of each pneumatic vibration source unit 1 can be selected according to different needs. By adjusting the depth and emission time of the secondary pneumatic vibration source in the array, the ghost signals generated during the sound generation process of the main pneumatic vibration source can be eliminated, and its extremely low-frequency sound generation performance can be optimized.

[0039] It should be noted that the diameters and lengths of the above operation room 105 and emission room 107 can be appropriately adjusted according to the actual situation, with ensuring the sealing performance as the primary standard.

[0040] After the above components are assembled, the air tightness needs to be checked again, and the overall debugging is carried out in a land lake. Connect the external high-pressure gas source, and gradually adjust the opening degree of the intake valve through the control system. Start from the minimum flow rate, slowly increase the gas flow rate, and at the same time observe the pressure changes in the operation room 105 and the emission room 107 and the flow rate changes in the intake pipe 102. Check whether the check valve 103 and the check pipe 104 are working properly to prevent the occurrence of gas backflow. Under different flow rate settings, test the frequency characteristics of the generated infrasound waves, and fine-tune the relevant parameters according to the test results to optimize the frequency range and energy output of the infrasound waves, ensure that the device can stably generate high-energy infrasound wave signals within a wide frequency band range, and check whether the components work together properly without problems such as abnormal vibration, noise or leakage.

[0041] The working process of the present invention is as follows: External high-pressure inert gas is connected to the intake valve 101 through an underwater pipeline. After the intake valve 101 precisely adjusts the gas flow according to preset parameters or real-time control signals, the gas enters the operation chamber 105 through the intake pipe 101. The pressure balance valve in the operation chamber 105 maintains a stable pressure. The air flow is modulated by the flow control valve and then enters the launch chamber through the channel connected by their flanges. At the same time, the flow sensor monitors the modulated air flow to further accurately distribute the gas flow direction to the launch chamber 107. The gas enters the launch chamber 107 through the cup-shaped flange 106 and the extension port. In the launch chamber 107, under the action of the launch chamber 107 with a precisely calibrated length, the gas is launched into the underwater environment. When the gas contacts the water, bubbles are generated. After the bubbles break due to the cavitation effect, infrasound waves with a wide frequency band, high energy, and excellent low-frequency characteristics are generated. At the same time, the system will adjust parameters such as the pressure of the launched gas and the launch interval according to the frequency of the generated infrasound waves.

[0042] During the whole process, the check valve 103 and the check pipe 104 prevent gas backflow. The air flow channel ensures stable and efficient gas transmission. The sensors monitor various key parameters in real time and feedback them to the control system for precise control of each component.

[0043] The above are only several specific embodiments of the present invention. However, the embodiments of the present invention are not limited thereto, and any changes that can be conceived by those skilled in the art should fall within the protection scope of the present invention.

Claims

1. A pneumatic seismic source for underwater acoustic generation, characterized in that: It comprises a plurality of pneumatic seismic source units (1), wherein some of the pneumatic seismic source units (1) are main pneumatic seismic sources, and the rest are auxiliary pneumatic seismic sources, the number of the auxiliary pneumatic seismic sources is not less than the number of the main pneumatic seismic sources, an array of auxiliary pneumatic seismic sources corresponding to each main pneumatic seismic source is distributed around the main pneumatic seismic source, and the emission ports of the plurality of pneumatic seismic source units (1) are all facing the same direction; Each of the pneumatic seismic source units (1) comprises an operating chamber (105) and a launching chamber (107) which are connected in one direction; the air inlet of the operating chamber (105) is connected to an external air source so as to introduce inert gas into the operating chamber (105); and the launching port is located at an end of the launching chamber (107) away from the operating chamber (105).

2. A pneumatic seismic source for underwater hypothermia generation according to claim 1, characterized in that: The emission port of the main pneumatic seismic source protrudes from the emission port of the auxiliary pneumatic seismic source.

3. The pneumatic seismic source for underwater hypothermia generation according to claim 1, characterized in that: The length of the launching chamber (107) is 5m-6m, the internal cavity of the launching chamber (107) is cylindrical, and the radius of the internal cavity of the launching chamber (107) is 250mm-280mm.

4. A pneumatic seismic source for underwater hypothermia generation according to claim 3, characterized in that: The length of the operating chamber (105) is 1m-2m, the internal cavity of the operating chamber (105) is cylindrical, and the radius of the internal cavity of the operating chamber (105) is equal to the radius of the internal cavity of the launch chamber (107).

5. The pneumatic seismic source for underwater hypothermia generation according to claim 1, characterized in that: The portion of the shell (108) of the pneumatic seismic source unit (1) where the emission port is located is in an arc shape.

6. The pneumatic seismic source for underwater hypothermia generation according to claim 1, characterized in that: A channel is provided on the connecting wall between the operating chamber (105) and the emission chamber (107), and a cup-shaped flange (106) is connected to the channel.

7. The pneumatic seismic source for underwater hypothermia generation according to claim 1, characterized in that: An air inlet of the operating chamber (105) is provided with an air inlet valve (101), the air inlet valve (101) is connected to an air inlet pipe (102), the air inlet pipe (102) is located in the operating chamber (105), and a check valve (103) is provided at an air outlet of the operating chamber (105), the check valve (103) is connected to a check pipe (104), and the check pipe (104) is arranged in parallel with the air inlet pipe (102) in the operating chamber (105).

8. The pneumatic seismic source for underwater hypothermia generation according to claim 1, characterized in that: The operating chamber (105) is provided with a flow control valve and a pressure balance valve. The flow control valve is arranged on a gas passage in the cup-shaped flange (106). After being modulated by the flow control valve, the gas flow enters the launch chamber (107) through the cup-shaped flange (106). The pressure balance valve is connected to the gas inlet of the operating chamber (105) so that the gas flow entering the operating chamber (105) is in a stable state. The operating chamber (105) is also provided with a pressure sensor and a temperature sensor. The launch chamber (107) is also provided with a flow sensor to monitor the gas flow in the launch chamber (107).

9. The pneumatic seismic source for underwater hypothermia generation according to claim 1, characterized in that: The array distribution includes: a plane array, a three-dimensional array, a ring array, a grid array, a spiral array, and a type array.

10. The pneumatic seismic source for underwater hypothermia generation according to claim 1, characterized in that: A connecting piece (109) is fixed on the outer wall of each of the pneumatic seismic source units (1), and the main pneumatic seismic source and the corresponding auxiliary pneumatic seismic source are connected and fixed via the connecting piece (109).

Images