CN112040371A - Low-frequency slotted liquid wall coupled transducer for deep water - Google Patents
Low-frequency slotted liquid wall coupled transducer for deep water Download PDFInfo
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- CN112040371A CN112040371A CN202010696284.8A CN202010696284A CN112040371A CN 112040371 A CN112040371 A CN 112040371A CN 202010696284 A CN202010696284 A CN 202010696284A CN 112040371 A CN112040371 A CN 112040371A
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R1/00—Details of transducers, loudspeakers or microphones
- H04R1/44—Special adaptations for subaqueous use, e.g. for hydrophone
Abstract
The invention discloses a low-frequency slotted liquid wall coupling transducer for deep water, which mainly comprises a radiation cover plate, wherein the radiation cover plate is positioned at the upper end and the lower end of the transducer, the radiation cover plate is sequentially bonded with a middle mass block through an end cover A, a piezoelectric ceramic vibrator and an end cover B, a prestress screw rod is penetrated in the middle of the radiation cover plate for fixing, a thin-wall cylindrical sleeve is a transducer shell, the thin-wall cylindrical sleeve is in decoupling connection with the middle mass block through a connecting rod and a decoupling material, four hoisting rods are in decoupling connection with the outer wall of the thin-wall cylindrical sleeve, and a central circle of the thin-wall cylindrical sleeve is. The invention has key performances of low frequency, very low frequency, small size, light weight, broadband, high power, high efficiency and the like, is more convenient to use and lower in cost, provides a technical basis for ocean acoustic chromatography subsurface buoy and system integration, realizes providing a technical means for monitoring a mesoscale process in a larger range, and serves remote underwater acoustic detection and communication, national ocean resource development and national ocean safety maintenance.
Description
Technical Field
The invention relates to the field of acoustic transducers, in particular to a low-frequency slotted liquid wall coupled transducer for deep water.
Background
The area of the earth covered by the ocean mostly belongs to deep sea with the depth of more than 4000 meters, and because only sound waves can realize remote propagation in the sea water, the real-time, dynamic and large-range monitoring of the ocean needs to be carried out by means of ocean acoustic chromatography technology. The ocean acoustic tomography is to take a 'snapshot' of the interior of a wide sea area by utilizing the ocean interior information carried by an ocean sound field, and a plurality of underwater acoustic transmitting transducers and receiving transducers are required to be used. The absorption loss of sound wave propagation in the ocean is reduced along with the reduction of frequency, and the transmitting transducer needs to work in a low-frequency broadband to realize real-time, dynamic and large-range monitoring of the ocean. In view of the transducer's adaptability and efficiency requirements, the transducer's volume and weight are as small as possible, transmit voltage response, as high as possible per watt source level, and easy impedance matching, thereby reducing the overall system's power consumption and size weight.
The technical fields of marine acoustic chromatography, remote underwater acoustic communication and the like need a transmitting transducer with high hydrostatic pressure resistance, low frequency and very low frequency, small size, light weight, broadband, high power and high efficiency, but all performance indexes of the transmitting transducer are difficult to consider in theory. For example, increasing the volume displacement of the transducer can make it emit with high power, and increasing the volume displacement of the transducer needs to increase the radiation area of the transducer, which means that the size of the transducer and the volume of active materials need to be increased, so that the low-frequency high-power transducers applied in the technical fields of marine acoustic tomography, remote underwater acoustic communication, etc. are large in size and heavy in weight. In addition, the energy converter for deep sea application must be powered by a battery, but the manpower and material resources required for frequently replacing a waste battery are large, so that the electro-acoustic conversion efficiency of the transmitting energy converter is high.
The Janus-Helmholtz transducer is a transducer proposed by French scholars Y.le Gall, and is formed by combining a Janus transducer and a Helmholtz resonant cavity, wherein the Janus transducer is a longitudinal vibration transducer with front and back double-sided radiation, and is originated from Greek myth and describes front and back two-sided holes or four-sided holes. The Helmholtz resonator is a cavity resonance effect discovered by Helmholtz, a german physicist. The Janus-Hammer Bell transducer is a transducer invented by Frederic Mosca of IXSEA, France. Hammer Bell stands for the name of a person.
The mainstream method for solving the above contradiction at present is to design an indirect excitation vibration type transducer based on a Helmholtz liquid cavity resonance mechanism:
the transducer has the advantages that longitudinal vibration is adopted to excite the transducer of the Helmholtz liquid cavity to work in a resonant mode, for example, the transducers invented by patents CN104282299A and CN104810013A are structurally characterized in that a cylindrical shell is sleeved on a composite rod transducer, the composite rod transducer is connected with the shell in a rigid and closed mode, a compliant pipe is further arranged in a cavity of the transducer invented by patent CN104282299A, and a Helmholtz pipe is further arranged in a through hole in a rear mass block of a composite rod of the transducer invented by patent CN 104810013A. The transducer is resistant to high hydrostatic pressure, has a considerable power-to-weight ratio, and can radiate high acoustic power. Because the transducer works in the state of Helmholtz liquid cavity resonance, the characteristic of narrow resonance bandwidth of the Helmholtz liquid cavity cannot be avoided, so the transducer has higher Q value and narrow working frequency band; in addition, the larger the size of the Helmholtz fluid chamber, the lower the resonant frequency, and thus, to operate such transducers at lower frequencies, the more bulky the transducer design and the less convenient it is to use.
The second is a JH-type transducer, for example, the transducers invented by patents CN102169685A and CN110010113A, which are structurally characterized in that a cylindrical cavity is sleeved on two ends of a Janus transducer to surround a Helmholtz resonant cavity with the Janus transducer, fluid inside the cavity is communicated with the outside, and the Janus transducer is rigidly connected with the cavity, wherein the transducer invented by patent CN110010113A is further provided with a bent metal disk at the front end of a radiation cover plate of the Janus transducer. The transducer adopts longitudinal vibration to excite the Helmholtz liquid cavity to work in a resonant mode, utilizes the resonance of the Helmholtz liquid cavity and the vibration mode of the radiation cover plate of the Janus transducer to couple to form broadband emission, and has higher power capacity and higher radiation sound power in the axial direction. The transducer invented by patent CN110010113A can make the sound energy of the transducer more focused in the radial direction by arranging a bent metal disk at the front end of the radiation cover plate of the Janus transducer. Because the transducer works in the state that the resonance of the Helmholtz liquid cavity is coupled with the vibration mode of the radiation cover plate of the Janus transducer, although the bandwidth is widened, the application of the transducer to the technical fields of ocean acoustic tomography and remote underwater acoustic communication still has limitation. Firstly, when the transducer is designed under the condition of lower working frequency, the size of a Helmholtz liquid cavity is larger, and the size and the weight of the Helmholtz liquid cavity are also larger; in addition, the acoustic field generated by Helmholtz liquid cavity resonance in the JH type transducer and Janus transducer radiation cover plate resonance has 180 degrees of inherent phase difference, so that the electro-acoustic conversion efficiency of the transducer is not high enough.
The JHB transducer invented by the patent US2013/0315037 is structurally similar to a JH type transducer, two thick circular ring shells are sleeved at two ends of a Janus transducer of the JHB transducer, the distance between the shells and the Janus transducer is far, the JHB transducer does not form a Helmholtz liquid cavity like the JH type transducer, the problem of large size of a low-frequency Helmholtz liquid cavity is avoided, and the JHB transducer is relatively compact in structure. Due to different structures, the working principle of the JHB transducer is different from that of the JH type transducer, the JHB transducer utilizes the coupling work of the radial vibration of two circular rings and the longitudinal vibration mode of the Janus transducer, the radial vibration of the circular rings is excited by seawater, and the sound conversion efficiency of the transducer is high due to the large contact area between the circular rings and the seawater. According to the transducer, two thick ring shells are sleeved at two ends of a Janus transducer, so that the problem of large size of a low-frequency Helmholtz liquid cavity is solved, the size is relatively compact, but the two thick ring shells still have large weight; in addition, if the radial vibration resonance frequency of the ring is set to 500Hz or less, the ring needs to be designed to be heavier in size and weight, and thus the JHB transducer having a center frequency lower than 500Hz is inconvenient to use.
Disclosure of Invention
The invention aims to overcome the defects in the prior art and provides a low-frequency slotted liquid wall coupled transducer for deep water.
The purpose of the invention is achieved by the following technical scheme: the deep-water low-frequency slotted liquid wall coupling transducer mainly comprises an end cover A, a connecting rod, a radiation cover plate, a prestressed screw rod, a middle mass block, a thin-wall cylindrical sleeve, hoisting rods, decoupling materials, a piezoelectric ceramic vibrator and an end cover B, wherein the radiation cover plate is positioned at the upper end and the lower end of the transducer, the radiation cover plate is sequentially bonded with the middle mass block through the end cover A, the piezoelectric ceramic vibrator and the end cover B, the prestress screw rod penetrates through the middle for fixing, the thin-wall cylindrical sleeve is a transducer shell, the thin-wall cylindrical sleeve is in decoupling connection with the middle mass block through the connecting rod and the decoupling materials, four hoisting rods are in decoupling connection with the outer wall of the thin-wall cylindrical sleeve, and a circle in the center of the thin-wall.
The two radiation cover plates, the two piezoelectric ceramic vibrators, the two end covers A and the two end covers B are sequentially bonded with the middle mass block to form the Janus transducer.
And after the prestressed screw and the radiation cover plate are screwed down, sealing is carried out by adopting a sealing mode combining polyurethane perfusion and rubber vulcanization.
The piezoelectric ceramic vibrator is penetrated with a prestress screw rod to apply prestress, and then becomes a high-power excitation source.
And the cavity opening enclosed by the thin-wall cylindrical sleeve and the transducer is in the axial direction.
The piezoelectric ceramic vibrator is formed by connecting and bonding an even number of piezoelectric ceramic circular rings in parallel, and the upper surface and the lower surface of the piezoelectric ceramic vibrator are bonded with the end cover A and the end cover B.
Two radiation cover plates of the transducer are firstly sealed by polyurethane pouring and then sealed by sound-transmitting rubber vulcanization.
Four symmetrical threaded holes are formed in the middle mass block to fix the four connecting rods.
The radiation cover plate is made of seawater aluminum materials resistant to seawater corrosion, the prestressed screw is made of No. 45 steel materials, and the thin-wall cylindrical sleeve, the end cover A, the end cover B, the connecting rod, the hoisting rod and the middle mass block are all made of 316L stainless steel materials.
The invention has the beneficial effects that: the invention has key performances of low frequency, very low frequency, small size, light weight, broadband, high power, high efficiency and the like, is more convenient to use and lower in cost, provides a technical basis for ocean acoustic chromatography subsurface buoy and system integration, realizes providing a technical means for monitoring a mesoscale process in a larger range, and serves remote underwater acoustic detection and communication, national ocean resource development and national ocean safety maintenance.
Drawings
Fig. 1 is a structural sectional view of the present invention.
Fig. 2 is a schematic structural diagram of the present invention.
Fig. 3 is a graphical illustration of sea test data for electroacoustical performance of the present invention.
Description of reference numerals: the structure comprises an end cover A1, a connecting rod 2, a radiation cover plate 3, a prestressed screw rod 4, a middle mass block 5, a thin-wall cylindrical sleeve 6, a hoisting rod 7, decoupling materials 8, a piezoelectric ceramic vibrator 9, an end cover B10 and a slit strip 11.
Detailed Description
The invention will be described in detail below with reference to the following drawings:
example (b): as shown in the attached drawing, the low-frequency slotted liquid wall coupled transducer for deep water mainly comprises an end cover A1, a connecting rod 2, a radiation cover plate 3, a prestressed screw rod 4, a middle mass block 5, a thin-wall cylindrical sleeve 6, a hoisting rod 7, a decoupling material 8, a piezoelectric ceramic vibrator 9 and an end cover B10, wherein the radiation cover plate 3 is positioned at the upper end and the lower end of the transducer, the radiation cover plate 3 is sequentially bonded with the middle mass block 5 through the end cover A1, the piezoelectric ceramic vibrator 9 and the end cover B10 to form a Janus transducer, the middle part of the radiation cover plate is fixed through the prestressed screw rod 4, and the prestressed screw rod 4 and the radiation cover plate 3 are sealed in a sealing mode combining polyurethane pouring and rubber vulcanization after being screwed. The piezoelectric ceramic vibrator 9 is penetrated with a prestress screw 4 to apply prestress, and then becomes a high-power excitation source. This more compact excitation configuration allows the transducer to have a considerable power to weight ratio, be smaller in size, and be more resistant to hydrostatic pressure than other transducers of the same frequency. The thin-wall cylindrical sleeve 6 is a transducer shell, the thin-wall cylindrical sleeve 6 is in decoupling connection with the middle mass block 5 through the connecting rods 2 and the decoupling materials 8, the four hoisting rods 7 are in decoupling connection with the outer wall of the thin-wall cylindrical sleeve 6, and a circle of the center of the thin-wall cylindrical sleeve 6 is slotted to form four slotted strips 11. Four symmetrical threaded holes are formed in the middle mass block 5 to fix the four connecting rods 2, and the connecting rods 2 are connected with the thin-wall cylindrical sleeve 6 through decoupling materials 8 and are fastened through screws. The cavity opening enclosed by the thin-wall cylindrical sleeve 6 and the transducer is in the axial direction. Two radiation cover plates 3 of the transducer are firstly sealed by polyurethane pouring and then sealed by sound-transmitting rubber vulcanization, so that the watertight reliability of the transducer is improved. The radiation cover plate 3 is made of seawater aluminum material resistant to seawater corrosion, the prestressed screw rod 4 is made of No. 45 steel material, and the thin-wall cylindrical sleeve 6, the end cover A1, the end cover B10, the connecting rod 1, the hoisting rod 7 and the middle mass block 5 are all made of 316L stainless steel material.
The piezoelectric ceramic vibrators 9 are formed by bonding an even number of piezoelectric ceramic rings in parallel, and the upper surface and the lower surface of each piezoelectric ceramic vibrator 9 are bonded with an end cover A1 and an end cover B10. The piezoelectric ceramic ring surface of the piezoelectric ceramic vibrator 9 bonded with the end cover is a negative electrode, the other surface is a positive electrode, then the two piezoelectric ceramic vibrators 9 are penetrated into the prestressed screw rod 4, one end of the prestressed screw rod is bonded with the middle mass block 5, and the other end of the prestressed screw rod is bonded with the two radiation cover plates 3 respectively and is fastened by screws. The adhesive is conductive epoxy resin. The anodes of the two piezoelectric ceramic vibrators 9 are communicated through a lead, and a positive wire is led out; the cathodes of the two piezoelectric ceramic vibrators 9 are communicated through a lead, and a cathode wire is led out.
The invention has the external dimension of 800mm 750mm and the weight of about 200 kg. The center of the Janus transducer is connected with a slotted thin-wall cylindrical sleeve 6 in a decoupling mode through four connecting rods 2 to form a Helmholtz resonant cavity with four strip-shaped slots in the axial direction and the radial direction. The piezoelectric ceramic vibrator 9 excites the low-frequency Helmholtz resonant cavity to resonate, and the slotted thin-wall cylindrical sleeve 6 is excited to vibrate radially by seawater. The slotted structure is easy for the low-frequency Helmholtz resonant cavity to excite the slotted thin-wall cylindrical sleeve 6 to vibrate radially, so that two vibration modes are coupled (liquid-wall coupling) to form low-frequency very-low-frequency broadband emission. In addition, the size of the Helmholtz resonant cavity with the opening in the axial direction is smaller.
In the design of the transducer, the greater the mass of the transducer, the lower its resonant frequency; the less rigid the transducer, the lower its resonant frequency. The invention effectively reduces the rigidity of the thin-wall cylindrical sleeve 6 and further reduces the resonance frequency of the whole transducer by slotting the thin-wall cylindrical sleeve 6 in a circle at the center. The thin-walled cylindrical sleeve 6 can therefore also be operated at low radial resonance frequencies by using a thin-walled cylindrical sleeve 6 of low weight.
The invention overcomes the defect of low electro-acoustic conversion efficiency of the traditional JH type transducer, and the acoustic field generated by the resonance of a Helmholtz liquid cavity of the traditional JH type transducer and the resonance of a radiation cover plate of the Janus type transducer has 180-degree inherent phase difference, so that the electro-acoustic conversion efficiency of the transducer is not high enough due to the coupling of the two modes. The radiation sound field of the invention is formed by the superposition of the sound field generated by the Helmholtz resonant cavity resonance and the radial resonance of the thin-wall cylindrical sleeve 6. The slots are formed in the center of the thin-wall cylindrical sleeve 6 in a circle, so that the phase difference between the resonance of the Helmholtz resonant cavity and the radial resonance of the thin-wall cylindrical sleeve 6 is changed, the coupling condition between sound radiation generated by the two resonances is improved, and the electro-acoustic conversion efficiency of the transducer is improved.
The invention is applied to a deep sea acoustic tomography system which is a topic under the national key research and development project of marine acoustic tomography theory, technology and application demonstration. In 11 months in 2018, the seventh five research institute of the Chinese vessel rework group participates in a ' key acoustic and offshore marine ecological marine instrument equipment standardized marine test ' organized by the seventh six good research institute of the Chinese vessel rework group, and the ' 2018-year shared voyage number (a northbound 993 test ship) goes to the east sea area to perform a sea test, so that the deep sea performance of the invention is verified. The test result proves that the center frequency of the invention is 460kHz when the transducer works in the deep sea of 1000 meters, the bandwidth of 3dB is 120Hz, the sending response of the sound source level of the transducer per volt is 139dB, the transmitting performance is excellent, the impedance matching is easy, and the sound source level can reach 199dB when the transducer is electrified by 1000 volts.
It should be understood that equivalent substitutions and changes to the technical solution and the inventive concept of the present invention should be made by those skilled in the art to the protection scope of the appended claims.
Claims (9)
1. A low-frequency slotted liquid wall coupled transducer for deep water is characterized in that: mainly comprises an end cover A (1), a connecting rod (2), a radiation cover plate (3), a prestressed screw rod (4), a middle mass block (5), a thin-wall cylindrical sleeve (6), a hoisting rod (7), decoupling materials (8), a piezoelectric ceramic vibrator (9) and an end cover B (10), wherein the radiation cover plate (3) is positioned at the upper end and the lower end of the transducer, the radiation cover plate (3) is sequentially bonded with the middle mass block (5) through the end cover A (1), the piezoelectric ceramic vibrator (9) and the end cover B (10), the prestress screw rod (4) is penetrated in the middle for fixing, the thin-wall cylindrical sleeve (6) is a transducer shell, the thin-wall cylindrical sleeve (6) is in decoupling connection with the middle mass block (5) through the connecting rod (2) and the decoupling materials (8), four hoisting rods (7) are connected on the outer wall of the thin-wall cylindrical sleeve (6) in decoupling mode, the central circle of the, four slit strips (11) are formed.
2. The low-frequency slotted liquid-wall coupled transducer for deep water of claim 1, wherein: the two radiation cover plates (3), the two piezoelectric ceramic vibrators (9), the two end covers A (1) and the two end covers B (10) are sequentially bonded with the middle mass block (5) to form the Janus transducer.
3. The low-frequency slotted liquid-wall coupled transducer for deep water of claim 1, wherein: and the prestressed screw (4) and the radiation cover plate (3) are screwed tightly and then sealed by adopting a sealing mode combining polyurethane perfusion and rubber vulcanization.
4. The low-frequency slotted liquid-wall coupled transducer for deep water of claim 1, wherein: the piezoelectric ceramic vibrator (9) penetrates into the prestress screw rod (4) to apply prestress, and then becomes a high-power excitation source.
5. The low-frequency slotted liquid-wall coupled transducer for deep water of claim 1, wherein: and the cavity opening enclosed by the thin-wall cylindrical sleeve (6) and the transducer is in the axial direction.
6. The low-frequency slotted liquid-wall coupled transducer for deep water of claim 1, wherein: the piezoelectric ceramic vibrator (9) is formed by connecting and bonding an even number of piezoelectric ceramic rings in parallel, and the upper surface and the lower surface of the piezoelectric ceramic vibrator (9) are bonded with the end cover A (1) and the end cover B (10).
7. The low-frequency slotted liquid-wall coupled transducer for deep water of claim 1, wherein: two radiation cover plates (3) of the transducer are firstly sealed by polyurethane pouring and then sealed by sound-transmitting rubber vulcanization.
8. The low-frequency slotted liquid-wall coupled transducer for deep water of claim 1, wherein: four symmetrical threaded holes are formed in the middle mass block (5) to fix the four connecting rods (2).
9. The low-frequency slotted liquid-wall coupled transducer for deep water of claim 1, wherein: the radiation cover plate (3) is made of seawater corrosion resistant seawater aluminum materials, the prestressed screw rod (4) is made of No. 45 steel materials, and the thin-wall cylindrical sleeve (6), the end cover A (1), the end cover B (10), the connecting rod (1), the hoisting rod (7) and the middle mass block (5) are all made of 316L stainless steel materials.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010696284.8A CN112040371A (en) | 2020-07-20 | 2020-07-20 | Low-frequency slotted liquid wall coupled transducer for deep water |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010696284.8A CN112040371A (en) | 2020-07-20 | 2020-07-20 | Low-frequency slotted liquid wall coupled transducer for deep water |
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| Publication Number | Publication Date |
|---|---|
| CN112040371A true CN112040371A (en) | 2020-12-04 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010696284.8A Pending CN112040371A (en) | 2020-07-20 | 2020-07-20 | Low-frequency slotted liquid wall coupled transducer for deep water |
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| CN (1) | CN112040371A (en) |
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2020
- 2020-07-20 CN CN202010696284.8A patent/CN112040371A/en active Pending
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