Bulb sound source release device applied to arctic ice region

Abstract

The invention discloses a bulb sound source release device applied to an arctic ice region, and relates to the technical field of underwater acoustic engineering. Aiming at low temperature, no power supply, deepwater and ice hole operation limitation in the arctic ice region, the device is driven by mechanical impact, and accurate breaking of the underwater vacuum bulb can be realized without a power supply. The device comprises a vacuum bulb cavity, a guide steel wire rope, a drop hammer, a firing pin assembly and an ice hole clamping frame. The vacuum bulb cavity comprises a pressure protection balance cavity, a pressure guide hole and a controllable knob; the drop hammer is released to fall freely along the steel wire rope, the firing pin is driven to break a vacuum bulb glass shell placed in an environment with the water depth larger than 50 m, implosion is triggered, and broadband sound waves are radiated. The device adopts a pressure protection balance cavity to counteract pre-compression of water pressure on the bulb, and the breaking reliability is ensured. The device is free of power supply, simple in structure, easy to arrange, large in action depth, good in generated sound source effect, and suitable for acoustic experiments and research in the Arctic ice region and the like.

Description

Technical Field

[0001] This invention belongs to the field of underwater acoustics technology, specifically relating to a light bulb sound source release device for use in the Arctic ice region. Background Technology

[0002] The Arctic region has a vast ocean area, which is of vital importance to the future development of nations, and underwater acoustic experiments in the Arctic are increasing year by year. Underwater sound sources are one of the important pieces of equipment in underwater acoustic experiments. Currently, commonly used sound sources in underwater acoustic experiments include transmitting transducers (arrays), explosion sound sources, electric spark sound sources, and plasma. However, the Arctic Environmental Protection Strategy (AEPS) requires people to pay attention to protecting the Arctic environment and restrict the use of high-power sound sources. Traditional electric spark sound sources consume a lot of energy and are prone to disturbing marine life, while air gun sound sources require complex air supply systems. Bulb sound sources produce wideband short pulse sound signals, which are less harmful to the marine environment than other high-power sound sources. They are considered wideband environmentally friendly sound sources with good safety. Du Zhipeng et al. derived a theoretical model for implosion in a spherical container of incompressible fluid, which can predict the implosion shock wave pressure, bubble radius, and bubble collapse time period based on parameters such as the radius of the spherical container and the hydrostatic pressure acting on it (Du Zhipeng, Du Jianye, Li Ying et al. Research on theoretical model of implosion in spherical container of incompressible fluid [C] / / 2015:5). It is evident that light bulb sound sources are not only safe but also controllable. Therefore, they can be used as important sound sources in the Arctic.

[0003] As early as 1963, Urick used glass bottles as sources of implosion sound (Urick R J. Implosions as Sources of Underwater Sound[J].The Journal of the Acoustical Society of America,1963,35(11):2026-2027). Marshall of the Woods Hole Oceanographic Institution pointed out that glass sphere sound sources may be used in the study of seabed sedimentary structures (Marshall Orr, Michael Schoenberg. Acoustic signatures from deep water implosions of spherical cavities[J].Journal of the Acoustical Society of America,1976,59(5):1155-1159). Heard et al. from the Atlantic Institute for Defence Studies in Canada studied ordinary light bulbs as sound sources and proposed that implosion bulbs could minimize environmental impact during shallow water operations (Heard GJ, McDonald M, Chapman NR, et al. Underwater light bulb implosions: a useful acoustic source [C] / / OCEANS'97.MTS / IEEE Conference Proceedings.IEEE, 1997). Ghiotto et al. from Curtin University in Australia conducted implosion experiments using vacuum spheres and provided the pressure-time series and spectrum of the implosion (Ghiotto A, Penrose JD. Investigating The Acoustic Properties Of The Underwater Implosions Of Light Globes And Evacuated Spheres. 2009). TCYang studied the acoustic reflection coefficient at the lower interface of the Arctic ice layer and obtained the ice reflection coefficient of acoustic signals with frequencies below 1kHz (Yang, TC Under ice reflectivities at frequencies below 1kHz[J]. Journal of the Acoustical Society of America, 1981, 70(3):841-851).SEDosso used a bulb sound source as an important sound source in Arctic cross-ice positioning research and shallow sea geoacoustic inversion experiments, achieving good results (Dosso, SE. Three-dimensional localization of transient acoustic sources using an ice-mounted geophone. [J]. Journal of the Acoustical Society of America, 2014). Domestically, Shao Zhihui et al. from the Institute of Acoustics, Chinese Academy of Sciences, designed and used a bulb sound source device, and used it to calibrate the shape of the receiving array in the International Marine Acoustics Joint Experiment in the Asian Seas (Shao Zhihui, Xiao Ling, Li Zhenglin et al. Performance Analysis of Vacuum Implosion Bulb Sound Source [C] / / Chinese Acoustical Society Youth Academic Conference. 2003). These past studies on bulb sound sources mostly involved operations in ordinary sea areas, and the release devices were mostly suitable for ordinary sea areas or near-shore ice areas. In recent years, Arctic scientific experiments have increased, generally conducted on research vessels. Most ice station experimental areas are far from the nearshore, with low ambient temperatures, high requirements for power supply equipment, and are far from the work vessel, making effective power supply difficult to obtain. Conventional light bulb sound source release devices lack sufficient impact energy in the absence of power, cannot break implosion light bulbs at depths of over 50 meters, have poor adaptability to deep-water environments, and are difficult to operate in ice areas. Therefore, in order to achieve deep-deep deployment in the Arctic ice areas and obtain a broadband environmentally friendly sound source, there is an urgent need to develop an underwater light bulb sound source excitation device that requires no power support, is small in size (ice hole diameter less than 30mm), and is easy to operate. Summary of the Invention

[0004] The purpose of this invention is to provide a light bulb sound source release device for use in the Arctic ice region. Addressing the challenges of low temperatures, distance from work vessels, great depths, and difficulty in obtaining effective power sources in the Arctic ice region, this invention utilizes the mechanical impact of the high-pressure environment in deep water to implode an underwater vacuum light bulb, thereby generating a broadband, environmentally friendly sound source in the Arctic ice region without the need for a power source.

[0005] A light bulb sound source release device for use in Arctic ice regions includes a vacuum bulb cavity, a guide steel wire rope, a drop hammer assembly, and a striker assembly;

[0006] The vacuum bulb cavity is equipped with a pressure protection and balancing chamber for accommodating the vacuum bulb. The pressure protection and balancing chamber has a pressure guiding hole on its side wall, which connects to external water. The bottom of the pressure protection and balancing chamber is equipped with a controllable knob for fixing the vacuum bulb. By rotating the controllable knob, the size of the vacuum bulb cavity can be adjusted, thereby fixing vacuum bulbs of different radii. The head of the vacuum bulb is equipped with a piston structure that fits the inner wall of the pressure protection and balancing chamber.

[0007] The guide steel wire rope passes vertically through the top of the vacuum bulb cavity and is used to adjust the underwater depth of the vacuum bulb;

[0008] The drop hammer assembly is sleeved on the guide steel wire rope and can fall freely along the rope to provide impact potential energy; the drop hammer assembly includes two detachable drop hammer sections and bolts for locking the drop hammer sections. The drop hammer sections are opened and closed by controlling the bolts; after the drop hammer sections are closed, a central hole is formed, and the guide steel wire rope passes through the central hole, with one end connected to the vacuum bulb cavity and the other end used to fix it to the edge of the Arctic ice cave.

[0009] The striking pin assembly is fixed at the end of the steel wire rope, facing the glass surface of the bulb. The striking pin assembly includes a tungsten steel needle tip and a buffer spring. When the drop hammer assembly falls along the guide steel wire rope, it can impact the striking pin assembly and drive the tungsten steel needle tip to shatter the vacuum bulb.

[0010] Furthermore, the diameter of the pressure guiding hole can be 2-3 mm, and the flow velocity can be ≤0.2 m / s, to ensure that after the pressure protection balance chamber is connected to the external water body through the pressure guiding hole, the pressure difference between the inside and outside is ≤0.5 MPa within 30 seconds.

[0011] Furthermore, the vacuum lamp can have a vacuum degree of 30kPa±5kPa, a volume of 50~500ml, and a glass thickness uniformity error of ≤0.1mm.

[0012] Furthermore, the drop hammer assembly can be made of stainless steel, the mass of the drop hammer assembly is ≥0.5kg, the drop height can be adjusted within the range of 10 to 100m, and the impact pressure of the tungsten steel needle tip is >500MPa, and the tip curvature radius of the tungsten steel needle tip can be ≤0.1mm, which is used to convert the potential energy of the drop hammer into impact kinetic energy to break the vacuum bulb.

[0013] Furthermore, the device also includes an ice cave bracket, which is fixed to the upper end of the guide steel wire rope and placed above the ice cave during use. The ice cave bracket can be made of polytetrafluoroethylene, and the part in contact with the Arctic ice cave can be provided with anti-slip texture to fix the end of the guide steel wire rope away from the vacuum bulb cavity, and the horizontal deviation after fixing is ≤5°.

[0014] Furthermore, the spring constant of the buffer spring can be 100 N / m, and the reset time after impact can be ≤3 seconds.

[0015] Furthermore, the bolt can be M6 specification, and the drop hammer segment can adopt a wedge-shaped interlocking structure with an opening and closing time of ≤10 seconds.

[0016] Furthermore, the pressure difference between the inside and outside of the vacuum bulb is constant at ≤10MPa, and the tightening torque of the controllable knob can be set to 5N·m.

[0017] Furthermore, the ratio of the piston structure to the pressure-bearing area of ​​the vacuum bulb can be 0.98 to 1.05.

[0018] Furthermore, the guide wire rope can be made of stainless steel. The upper end of the guide wire rope is connected to the ice cave bracket, and the lower end of the guide wire rope is connected to the vacuum bulb cavity, which is used to adjust the underwater depth of the vacuum bulb.

[0019] Furthermore, the overall maximum diameter of the device is ≤28mm, so as to be compatible with Arctic ice caves with a diameter of ≤30mm.

[0020] The working principle of this invention is as follows:

[0021] 1) Water pressure balance mechanism: The pressure guide hole and the bulb head piston-like structure keep the pressure difference between the inside and outside of the bulb constant at ≤10MPa (to prevent the bulb from breaking due to water pressure); to ensure the stability of the acoustic performance of the bulb sound source, the thickness, volume and vacuum degree of the bulb glass are kept consistent, the ratio of the piston structure of the bulb head to the pressure-bearing area of ​​the bulb is less than 1.05, of which 5% offsets friction loss; the flow velocity of the pressure guide hole is designed to be no more than 0.2m / s to ensure the pressure balance between the inside and outside of the pressure protection balance chamber.

[0022] 2) Energy Amplification Structure: Drop hammer mass (≥0.5kg) × drop height (10~100m) → concentrated release of kinetic energy of the firing pin (pin tip pressure >500MPa); the potential energy of the drop hammer is transferred to the firing pin via the kinetic energy of the steel wire rope, thus focusing the kinetic energy of the firing pin, thereby causing the bulb to implode and convert mechanical energy into sound energy. Additionally, after the bulb implodes, the hydrostatic pressure compresses the initial low-pressure bubble, increasing the water's kinetic energy and further converting it into sound energy. This manifests as the bulb glass breaking, forming an initial bubble with a radius R0 less than 0.05m and a pressure P0 less than 30kPa. The initial bubble then expands, but the hydrostatic pressure prevents it from expanding indefinitely, converting the bubble's kinetic energy into potential energy. The hydrostatic pressure then accelerates the bubble's collapse, converting kinetic energy into sound energy at the moment of collapse.

[0023] 3) Depth adjustment mechanism: The drop hammer is divided into sections and bolts and knobs to form a drop hammer that can be opened flexibly. Therefore, the steel wire rope can be freely replaced to adjust the depth of the bulb sound source.

[0024] 4) Acoustic spectrum control: The main frequency of the implosion sound can be adjusted by changing the bulb diameter (50-500ml) and the hammering depth (experiments show that the main frequency of the bulb in 500ml water at a depth of 60m is 400Hz±10%).

[0025] Compared with existing excitation devices such as explosion sound sources, electric spark sound sources, and shipborne light bulb sound sources, the present invention has the following advantages:

[0026] 1. Autonomous operation without power supply: It adopts mechanical impact drive, which does not require batteries or external power supply. It can still work stably in the low temperature environment of -50℃, solving the problem of power supply in the Arctic ice area.

[0027] 2. Ultra-small size suitable for ice areas: The device of this invention has a small diameter, light weight, and simple operation. The maximum diameter of the overall device is ≤28mm, which can be deployed through the Arctic standard ice cave (diameter ≥30mm). Only one person is needed to complete the bulb replacement and depth adjustment during operation.

[0028] 3. Adaptability to deep water and high pressure: Through the pressure guide hole + piston-type pressure balance mechanism, the pressure difference between the inside and outside of the bulb is kept constant at ≤10MPa. When deployed in water depth of 50 to 100 meters, the self-breakage rate of the bulb is ≤1%, which solves the problem of premature breakage in deep water of traditional devices.

[0029] 4. High energy conversion efficiency: The impact pin of this invention has high hardness and low energy loss, and can be reused multiple times; the drop hammer (≥0.5kg) and the impact pin (tungsten steel tip) form an energy focusing structure with a potential energy to kinetic energy conversion efficiency of ≥85% and a tip pressure of over 500MPa, ensuring a light bulb breaking success rate of ≥90% within a 100-meter water depth.

[0030] 5. Controllable sound source performance: The cavity knob design allows for independent adjustment of the bulb size, thereby adjusting the sound source performance (resonance frequency, sound source level, etc.); by replacing bulbs of different volumes (50-500ml) and adjusting the placement depth, precise control of the sound source level (160-200dB ref 1μPa@1m) and the main frequency (200-1000Hz) can be achieved to meet the different acoustic experimental needs in the Arctic ice region.

[0031] 6. High reusability: The impact pin assembly contains a buffer spring, and the reset time after a single impact is ≤2 seconds. It can be reused ≥50 times, reducing experimental costs. Attached Figure Description

[0032] Figure 1 This invention illustrates the relationship between the resonant frequency, sound level, and depth of light bulbs with different radii. Specifically, 'a' represents the relationship between the resonant frequency and depth of light bulbs with different radii; and 'b' represents the relationship between the sound level and depth of light bulbs with different radii.

[0033] Figure 2 This is a schematic diagram of the overall structure of the light bulb sound source release device.

[0034] Figure 3 This describes the composition and structure of a vacuum bulb cavity.

[0035] Figure 4 The composition and structure of the drop hammer and striking pin assembly.

[0036] Figure 5 This is a time-domain diagram of the light bulb sound source signal generated by the present invention.

[0037] Figure 6 This is a time-frequency diagram of the light bulb sound source signal generated by the present invention. Detailed Implementation

[0038] To make the objectives, technical solutions, and advantages of this invention clearer, the following embodiments will be used in conjunction with the accompanying drawings to further illustrate the invention. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. Rather, the invention encompasses any substitutions, modifications, equivalent methods, and solutions made within the spirit and scope of the invention as defined by the claims. Furthermore, to provide the public with a better understanding of the invention, some specific details are described in detail below. Those skilled in the art will fully understand the invention even without these detailed descriptions.

[0039] To realize an underwater vacuum bulb sound source and its release device for application in the Arctic ice region, the present invention provides the following technical solution: The design of the bulb sound source release device mainly includes the vacuum bulb cavity design, the bulb sound source guide wire rope laying depth design, the impact pin design, and the drop hammer design. The specific steps are as follows:

[0040] 1. Vacuum bulb cavity design.

[0041] First, it is necessary to ensure that the size, glass thickness, and vacuum level of the vacuum bulb 102 are consistent. Based on the bulb holder size designed in this embodiment, the bulb diameter should not exceed 15cm. After evacuation, the atmospheric pressure inside the bulb should be uniformly 30kPa. A controllable knob 105 is located below the pressure protection balance chamber 103. Turning the controllable knob 105 counterclockwise opens the vacuum bulb 102, places it inside the pressure protection balance chamber 103, and then tightens it instantly clockwise. The pressure protection balance chamber 103, through the controllable knob 105, can fix different types of vacuum bulbs 102, thereby autonomously adjusting the resonant frequency and sound level of the vacuum bulb 102 sound source. The ratio of the bulb head's piston-like structure to the bulb's pressure-bearing area is less than 1.05, with 5% offsetting frictional losses. The pressure protection balancing chamber 103 is connected to external water through a pressure guiding hole 104. The diameter of the pressure guiding hole 104 can be designed to be 2-3 mm, and the flow velocity of the pressure guiding hole 104 is designed to be no more than 0.3 m / s. This flow velocity ensures that the pressure inside and outside the balancing chamber reaches equilibrium within 30 seconds, avoiding pressure fluctuations that could cause the bulb to break. These designs are mainly to balance the water pressure inside and outside the vacuum bulb protection chamber, while also preventing the bulb from shattering upon impact. The ratio of the bulb head piston structure to the bulb pressure-bearing area of ​​the vacuum bulb 102 is preferably 0.98-1.05, with 5% used to offset the frictional loss between the piston and the chamber wall, ensuring a pressure balance accuracy of ≤ ±0.5 MPa.

[0042] 2. Design of the depth of the guide wire rope for the light bulb sound source.

[0043] Based on the required sound source level, the first step is to lay the light bulb sound source guide wire rope 201. The empirical relationship between the laying depth and the sound source level is as follows:

[0044] SL=160+26*lg(h) (1)

[0045] Where SL is the sound source level (dB ref 1μPa@1m), h is the depth of the bulb underwater (unit: m); lg is a logarithmic function to base 10. Considering that different bulbs will vary due to differences in radius, vacuum level, and glass material, we can assume that the variation is Δt. Therefore, the relationship between the placement depth and the sound source level is:

[0046] SL=160+26*lg(h)+Δt (2)

[0047] Where SL is the sound source level (unit: dB ref 1μPa@1m); h is the depth of the bulb underwater (unit: m); Δt is the correction amount caused by differences in bulb radius, vacuum degree, and glass material (unit: dB); lg is a logarithmic function with base 10.

[0048] To achieve a sound source level of 180 dB, assuming Δt is 3 dB, a preliminary calculation shows that the depth h must be greater than 5 m. Furthermore, based on the empirical relationship between deployment depth and resonant frequency:

[0049] f = k * (g * (h + 10)) 5 / 6 (3)

[0050] Where f is the resonant frequency, g is the gravitational acceleration, and k is a coefficient that varies with the bulb radius, vacuum level, and glass material. If k is taken as 1, and the desired resonant frequency is 200Hz, the depth h can be preliminarily calculated to be approximately 50m.

[0051] Therefore, the placement depth can be flexibly adjusted based on the requirements for the sound source level and resonant frequency during the Arctic experiment. Of course, if there are direct requirements for the placement depth of the sound source, all three factors must be considered together.

[0052] 3. Strike pin design.

[0053] The impact pin assembly 401 includes a tungsten carbide needle tip 402 and a buffer spring 403. The impact pin assembly 401 adopts a stepped distribution structure; the first and second stages are made of stainless steel, while the third stage is made of tungsten carbide needle tip 402 with a tip curvature radius ≤0.1mm. The first stage structure receives the impact of the falling hammer 301 and has a larger curvature radius of approximately 0.5mm, while the second stage has a curvature radius of approximately 0.3mm. After the falling hammer 301 strikes, the third-stage needle tip can quickly shatter the glass, releasing the energy of the glass implosion. Under the action of the buffer spring 403, the impact pin assembly 401 can quickly return to its original position.

[0054] 4. Drop hammer design.

[0055] The drop hammer 301 has two structural parts, divided into two sections from top to bottom, with a bolt hole in the middle. A single bolt is used to lock them together, making them one unit. Specifically, considering buoyancy and water resistance after falling into the water, the drop hammer 301 is made of stainless steel, with a designed weight greater than 0.25 kg. The drop hammer section 302 uses a wedge-shaped interlocking structure, locked by bolt 303, with an opening and closing time of ≤10 seconds, facilitating quick replacement of the wire rope and adjustment of depth; bolt 303 can be an M6 bolt. When the falling height exceeds 2m, the kinetic energy of the striking pin assembly 401 is released in a concentrated manner (tiptoe pressure >50MPa); the potential energy of the drop hammer 301 is transferred to the striking pin assembly 401 via the guide wire rope 201, focusing the kinetic energy and causing the vacuum bulb 102 to implode, converting mechanical energy into acoustic energy. Additionally, after the bulb implodes, the hydrostatic pressure compresses the initial low-pressure bubble, increasing the water's kinetic energy and further converting it into acoustic energy. The process begins with the glass of a light bulb breaking, forming an initial bubble with a radius R0 less than 0.05m and a pressure P0 less than 30kPa. The initial bubble then expands, but the hydrostatic pressure prevents it from expanding indefinitely. The bubble's kinetic energy is converted into potential energy, and the hydrostatic pressure accelerates the work, compressing the bubble and causing it to collapse faster. At the moment of collapse, the kinetic energy is converted into sound energy.

[0056] The bubble pulsation equation (simplified Rayleigh-Plesset) is as follows:

[0057]

[0058] In the formula, R is the bubble radius. Let be the first derivative of the bubble radius (unit: m / s). The second derivative of the bubble radius (unit: m / s) 2 ), P h Let P0 be the hydrostatic pressure, P0 be the internal pressure of the bubble, σ be the surface tension, and μ be the viscosity coefficient. Additionally, the sound energy conversion efficiency, after experimental fitting, is:

[0059]

[0060] In the formula, E S For sound energy; E mIt is mechanical energy.

[0061] Finally, based on this embodiment, 12 deep-water impact sound-generating experiments were conducted in the Arctic ice region, and the results are shown in Table 1:

[0062] Table 1. Statistics of 12 Deep-Water Breaking Sounds in the Arctic Ice Zone

[0063]

[0064] According to Table 1, the success rate of sound generation upon impact is 90% when the bulb sound source release depth is between 50 and 100 m. No sound was heard from the bulb on the fourth attempt. The reason for the lack of sound generation was found to be that the vacuum level inside the bulb did not meet the standard. Since there is generally a 20% spare bulb sound source in the experiment, a 90% sound generation rate is sufficient for experiments in the Arctic ice region.

[0065] The process of the coordinated operation of the components of the light bulb sound source release device applied in the Arctic ice region can be referred to as follows:

[0066] 1) Drill an ice hole with a diameter of ≥30mm in the Arctic ice surface, fix the ice hole holder 501 to the edge of the ice hole, and lock it with bolts to ensure that its horizontal deviation is ≤5°; put the vacuum bulb 102 (select 50~500ml volume according to experimental needs) into the pressure protection balance chamber 103, tighten the controllable knob 105 (tightening torque 5N·m) to fix the bulb. At this time, the pressure guide hole 104 begins to connect to the external water body. Within 30 seconds, the pressure inside and outside the pressure protection balance chamber 103 reaches balance (pressure difference ≤0.5MPa);

[0067] 2) Disassemble the drop hammer block 302 (loosen the bolt 303), connect one end of the bulb sound source guide wire rope 201 to the top hanging point of the vacuum bulb cavity 101, and pass the other end through the center hole of the drop hammer 301 and fix it to the ice cave bracket 501; calculate the required deployment depth according to formulas (2) and (3), slowly lower the vacuum bulb cavity 101 to the target water depth, close the drop hammer block 302 and lock the bolt 303;

[0068] 3) Raise the drop hammer 301 to the set height (10-100m, adjusted according to water depth), release the drop hammer 301 so that it falls freely along the bulb sound source guide steel wire rope 201. The drop hammer 301 impacts the primary structure of the striker assembly 401. The impact force is transmitted to the tungsten steel needle tip 402 through the secondary structure. The needle tip breaks the vacuum bulb 102 with a pressure of >500MPa.

[0069] 4) After the vacuum bulb 102 implodes, the firing pin assembly 401 returns to its initial position within 3 seconds under the action of the buffer spring 403; the drop hammer block 302 is disassembled, the bulb sound source guide steel wire rope 201 and the vacuum bulb cavity 101 are recovered, and after replacing the new vacuum bulb 102, it can be deployed again. A single firing pin assembly 401 can be reused ≥50 times.

[0070] Based on the above steps, this invention obtains an underwater broadband environmentally friendly sound source by breaking an implosion vacuum bulb at a set depth underwater and releasing sound energy.

[0071] Figures 1-6 An example of using the device of the present invention to release a light bulb sound source in the Arctic ice region is given. Specific embodiments are described with reference to the figures.

[0072] Figure 1 This graph shows the relationship between the resonant frequency and sound level of a sound source and the depth of an underwater vacuum bulb when the diameter (d) is 0.05m, 0.07m, and 0.09m, for bulbs of the same model and vacuum level. This graph allows for the selection of the bulb radius and placement depth as needed. Figure 1 In the diagram, 'a' represents the relationship between the resonant frequency of a light bulb with different radii and depth, and 'b' represents the relationship between the sound level of a light bulb with different radii and depth.

[0073] Figure 2 A schematic diagram of the overall structure of the light bulb sound source release device; Figure 3 A detailed schematic diagram of the vacuum bulb cavity of the bulb sound source release device; Figure 4 Detailed composition and structure of the drop hammer and striking pin assembly; Figure 5 This is a time-domain diagram of the light bulb sound source signal generated by this method; Figure 6 This is the time-frequency diagram of the light bulb sound source signal generated by this method.

[0074] The device is an integrated structure consisting of a vacuum bulb chamber, a guide steel wire rope, a drop hammer, a striker assembly, and an ice cave frame. Specifically, it includes a vacuum bulb chamber 101, a guide steel wire rope 201, a drop hammer 301, a striker assembly 401, an ice cave frame 501, a vacuum bulb 102, a pressure protection balance chamber 103, a pressure guiding hole 104, a controllable knob 105, a drop hammer block 302, a bolt 303, a tungsten carbide needle tip 402, and a buffer spring 403.

[0075] The vacuum bulb cavity consists of a vacuum bulb 102, a pressure protection and balance cavity 103, a pressure guiding hole 104, and a controllable knob 105.

[0076] The guide wire rope 201 is made of stainless steel, and is connected and fixed to the ice cave bracket 501 at the top and connected to the vacuum bulb cavity at the bottom.

[0077] The drop hammer 301 is made of stainless steel and has a hollow, segmented structure at the top. A bolt 303 is built into the upper middle part of the drop hammer, which can be freely opened and closed and disassembled into drop hammer segment 302 by means of the bolt.

[0078] The firing pin assembly 401 includes a tungsten carbide needle tip 402 and a buffer spring 403, with a needle tip curvature radius ≤ 0.1 mm.

[0079] The following are the four key technical mechanisms by which the device of this invention achieves its core functions:

[0080] 1) Water pressure balance mechanism: Through the coordinated design of the pressure guide hole 104 and the piston-like structure of the bulb head, the pressure difference between the inside and outside of the vacuum bulb 102 is kept constant at ≤10MPa (to avoid premature self-breakage of the bulb due to deep water pressure); to ensure the stability of the acoustic performance of the bulb sound source, the glass thickness, volume, and vacuum degree of the vacuum bulb 102 must be strictly consistent (the vacuum degree is uniformly set at 30kPa); the ratio of the pressure-bearing area of ​​the piston structure of the bulb head to that of the vacuum bulb 102 is less than 1.05, of which 5% of the area difference is used to offset the frictional loss between the piston and the wall of the pressure protection balance chamber 103; the flow velocity of the pressure guide hole 104 is designed to be no more than 0.2m / s to ensure that the pressure inside and outside the pressure protection balance chamber 103 reaches balance within 30 seconds (pressure difference ≤0.5MPa), further ensuring the safety of the vacuum bulb 102 during the deployment process.

[0081] 2) Energy Amplification Structure: An energy transfer system of "falling hammer 301 - striking pin assembly 401" is adopted. The mass of the falling hammer 301 is set to ≥0.5kg, and the falling height can be adjusted within the range of 10-100m. Through the accumulation of potential energy of "falling hammer mass × falling height", it is transferred to the kinetic energy of the striking pin assembly 401 through the bulb sound source guide steel wire rope 201, and finally realizes the concentrated release of kinetic energy of the tungsten steel needle tip 402 (needle tip pressure >500MPa). This kinetic energy focusing effect can quickly shatter the vacuum bulb 102, causing the bulb to implode and convert mechanical energy into sound energy. In addition, after the vacuum bulb 102 implodes, the hydrostatic pressure of the deep water will compress and do work on the initial low-pressure bubble (radius R0 <0.05m and pressure P0 <30kPa when it is formed): the initial bubble first expands in the water, the hydrostatic pressure prevents it from expanding indefinitely and converts the bubble's kinetic energy into potential energy, and then the hydrostatic pressure accelerates the compression of the bubble, causing it to collapse. At the moment of bubble collapse, the water kinetic energy is further converted into sound energy, improving the sound source level output.

[0082] 3) Depth adjustment mechanism: The drop hammer 301 adopts a detachable structure of "drop hammer block 302 + bolt 303". Loosening the bolt 303 can flexibly open the drop hammer block 302, which is convenient for freely changing or adjusting the length of the bulb sound source guide steel wire rope 201. Combined with the fixing effect of the ice cave bracket 501, the placement depth of the vacuum bulb 102 (including the vacuum bulb cavity 101) can be precisely adjusted by controlling the length of the lowering of the steel wire rope, so as to meet the acoustic experiment requirements of different water depths (50~100m).

[0083] 4) Acoustic spectrum control: Precise control of the implosion sound frequency is achieved through dual-variable adjustment: first, the diameter (i.e., volume) of the vacuum bulb 102 is changed (selectable range 50-500ml); second, the hammering depth (deployment depth) of the vacuum bulb 102 is adjusted. Experimental data shows that when the deployment depth is 60m and the volume of the vacuum bulb 102 is 500ml, the implosion sound frequency can reach 400Hz±10%, and the overall adjustable frequency range covers 200-1000Hz, meeting the frequency requirements of broadband acoustic experiments in the Arctic ice region.

[0084] To verify the technical effectiveness of this invention, a field experiment was conducted in the Arctic ice region. The light bulb sound source signal emitted by this device was received by an underwater hydrophone (with a sensitivity of -170dB ref=1V / μPa) at a distance of approximately 50m from the sound source. The time-domain and time-frequency domain graphs of the sound source signal are shown below. Figure 5 and 6 As shown. From Figure 5 It can be seen that the generated signal is a pulse signal with a pulse length of approximately 0.1 seconds and a peak value of approximately 2.5V, resulting in a peak sound pressure level exceeding 200dB. Figure 6 It can be seen that the generated signal is a pulse broadband signal with a clear energy distribution within the 20kHz frequency band.

[0085] During the experiment, the ambient temperature was -42℃. The device worked continuously for 8 hours without any freezing of components or performance degradation. The 201 (316 stainless steel) guide wire rope for the bulb sound source showed no signs of corrosion, proving the stability of the device in the Arctic low temperature and high salt environment.

[0086] The above embodiments are merely preferred embodiments of the present invention and should not be considered as limiting the scope of the present invention. All equivalent variations and improvements made within the scope of the present invention should still fall within the patent coverage of the present invention.

Claims

1. A light bulb sound source release device for use in Arctic ice regions, characterized in that... Includes vacuum bulb chamber, guide steel wire rope, drop hammer assembly and impact pin assembly; The vacuum bulb cavity is equipped with a pressure protection and balancing chamber for accommodating the vacuum bulb. The pressure protection and balancing chamber has a pressure guiding hole on its side wall, which connects to external water. The bottom of the pressure protection and balancing chamber is equipped with a controllable knob for fixing the vacuum bulb. By rotating the controllable knob, the size of the vacuum bulb cavity can be adjusted, thereby fixing vacuum bulbs of different radii. The head of the vacuum bulb is equipped with a piston structure that fits the inner wall of the pressure protection and balancing chamber. The guide steel wire rope passes vertically through the top of the vacuum bulb cavity and is used to adjust the underwater depth of the vacuum bulb; The drop hammer assembly is sleeved on the guide steel wire rope and can fall freely along the rope to provide impact potential energy; the drop hammer assembly includes two detachable drop hammer sections and bolts for locking the drop hammer sections. The drop hammer sections are opened and closed by controlling the bolts; after the drop hammer sections are closed, a central hole is formed, and the guide steel wire rope passes through the central hole, with one end connected to the vacuum bulb cavity and the other end used to fix it to the edge of the Arctic ice cave. The striking pin assembly is fixed at the end of the steel wire rope, facing the glass surface of the bulb. The striking pin assembly includes a tungsten steel needle tip and a buffer spring. When the drop hammer assembly falls along the guide steel wire rope, it can impact the striking pin assembly and drive the tungsten steel needle tip to shatter the vacuum bulb.

2. The light bulb sound source release device as described in claim 1, characterized in that... The diameter of the pressure guiding hole is 2-3 mm, and the flow velocity is ≤0.2 m / s, to ensure that after the pressure protection balance chamber is connected to the external water body through the pressure guiding hole, the pressure difference between the inside and outside is ≤0.5 MPa within 30 seconds.

3. The light bulb sound source release device as described in claim 1, characterized in that... The vacuum bulb has a vacuum degree of 30kPa±5kPa, a volume of 50~500ml, and a glass thickness uniformity error of ≤0.1mm.

4. The light bulb sound source release device as described in claim 1, characterized in that... The mass of the drop hammer assembly is ≥0.5kg, the drop height is adjustable within the range of 10 to 100m, and the impact pressure of the tungsten steel needle tip is >500MPa, and the radius of curvature of the tungsten steel needle tip is ≤0.1mm. It is used to convert the potential energy of the drop hammer into impact kinetic energy to break the vacuum bulb.

5. The light bulb sound source release device as described in claim 1, characterized in that... It also includes an ice cave holder, which is fixed to the upper end of the guide steel wire rope and placed above the ice cave during use.

6. The light bulb sound source release device as described in claim 5, characterized in that... The ice cave bracket is made of polytetrafluoroethylene and has anti-slip textures at the contact point with the Arctic ice cave. It is used to fix the end of the guide steel wire rope away from the vacuum bulb cavity, and the horizontal deviation after fixing is ≤5°.

7. The light bulb sound source release device as described in claim 1, characterized in that... The spring constant of the buffer spring is 100 N / m, and the reset time after impact is ≤3 seconds.

8. The light bulb sound source release device as described in claim 1, characterized in that... The drop hammer blocks adopt a wedge-shaped interlocking structure with an opening and closing time of ≤10 seconds.

9. The light bulb sound source release device as described in claim 1, characterized in that... The pressure difference between the inside and outside of the vacuum bulb is kept constant at ≤10MPa, and the tightening torque of the controllable knob is set to 5. .

10. The light bulb sound source release device as described in claim 1, characterized in that... The ratio of the piston structure to the pressure-bearing area of ​​the vacuum bulb is 0.98 to 1.05.

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