CN113639852B - Torsion type non-inertial vector hydrophone - Google Patents
Torsion type non-inertial vector hydrophone Download PDFInfo
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- CN113639852B CN113639852B CN202110818475.1A CN202110818475A CN113639852B CN 113639852 B CN113639852 B CN 113639852B CN 202110818475 A CN202110818475 A CN 202110818475A CN 113639852 B CN113639852 B CN 113639852B
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- vector hydrophone
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- vector
- piezoelectric ceramic
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- 239000000919 ceramic Substances 0.000 claims abstract description 27
- 230000035945 sensitivity Effects 0.000 claims abstract description 12
- 239000000463 material Substances 0.000 claims description 9
- 230000001133 acceleration Effects 0.000 claims description 7
- 239000002245 particle Substances 0.000 claims description 6
- 239000002131 composite material Substances 0.000 claims description 5
- 238000000034 method Methods 0.000 claims description 5
- 230000010287 polarization Effects 0.000 claims description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 5
- 229910000838 Al alloy Inorganic materials 0.000 claims description 3
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 3
- 229910000831 Steel Inorganic materials 0.000 claims description 3
- 239000000956 alloy Substances 0.000 claims description 3
- 239000011324 bead Substances 0.000 claims description 3
- 229910052802 copper Inorganic materials 0.000 claims description 3
- 239000010949 copper Substances 0.000 claims description 3
- 239000003822 epoxy resin Substances 0.000 claims description 3
- 239000011521 glass Substances 0.000 claims description 3
- 229910052751 metal Inorganic materials 0.000 claims description 3
- 239000002184 metal Substances 0.000 claims description 3
- 229920000647 polyepoxide Polymers 0.000 claims description 3
- 239000010959 steel Substances 0.000 claims description 3
- 230000003068 static effect Effects 0.000 claims description 2
- 230000009466 transformation Effects 0.000 claims 1
- 230000007547 defect Effects 0.000 abstract description 3
- 238000010008 shearing Methods 0.000 abstract description 2
- 238000010586 diagram Methods 0.000 description 6
- 239000000725 suspension Substances 0.000 description 5
- 238000001514 detection method Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01H—MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES
- G01H11/00—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by detecting changes in electric or magnetic properties
- G01H11/06—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by detecting changes in electric or magnetic properties by electric means
- G01H11/08—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by detecting changes in electric or magnetic properties by electric means using piezoelectric devices
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Transducers For Ultrasonic Waves (AREA)
- Measurement Of Velocity Or Position Using Acoustic Or Ultrasonic Waves (AREA)
- Measurement Of Mechanical Vibrations Or Ultrasonic Waves (AREA)
Abstract
The invention discloses a torsion type non-inertial vector hydrophone, and belongs to the technical field of vibration sensors. The invention solves the problems of limited working bandwidth and lower sensitivity of the non-inertial vector hydrophone in the existing underwater sound engineering field. The invention applies the shearing motion of the piezoelectric ceramics to the non-inertial vector hydrophone for the first time, and utilizes d 15 The high piezoelectric parameters realize the high-sensitivity receiving of the non-inertial vector hydrophone under the condition of small volume, the non-inertial vector hydrophone does not need differential output, vector signals can be directly output, differential errors of the signals are eliminated, and meanwhile, the defect that the inertial vector hydrophone needs to be suspended is avoided.
Description
Technical Field
The invention relates to a torsion type non-inertial vector hydrophone, and belongs to the technical field of vibration sensors.
Background
A vector hydrophone is an underwater acoustic transducer that can receive acoustic wave vector signals (particle velocity, particle acceleration, or particle displacement) under water. The method can be applied to the aspects of sonobuoys, submerged buoy systems, underwater target detection, marine environment background noise measurement, long-distance underwater sound detection and the like. Vector hydrophones are mainly divided into inertial vector hydrophones and non-inertial vector hydrophones from a large class. Although the low-frequency sensitivity of the existing inertial type vector hydrophone (same-vibration type vector hydrophone) is higher, a suspension system is usually needed during use, unstable system characteristics and inconvenient use can be brought by repeated suspension, and meanwhile, the whole volume of the vector hydrophone is overlarge by the suspension system. Although a suspension system is not needed, the non-inertial type vector hydrophone (differential pressure type vector hydrophone) is convenient to use, the signal is usually in differential output, errors are introduced, the bandwidth is limited, and the sensitivity is low.
At present, the characteristics of natural cosine directivity and multichannel information output of the vector hydrophone are increasingly emphasized, and the defects that the inertial type vector hydrophone needs to be hung, the non-inertial type vector hydrophone has limited bandwidth and low sensitivity limit the further application of the vector hydrophone. It is therefore desirable to provide a vector hydrophone that does not require suspension, has a large bandwidth, and has a high sensitivity.
Disclosure of Invention
The invention provides a torsion type non-inertial vector hydrophone, which aims to solve the problems of limited working bandwidth and low sensitivity of the non-inertial vector hydrophone in the existing underwater sound engineering field.
The technical scheme of the invention is as follows:
the utility model provides a torsion type non-inertial vector hydrophone, includes receiving stick 1, overcoat 2, piezoceramics ring 3 and lining pole 4, piezoceramics ring 3 closely suit on lining pole 4, overcoat 2 closely suit is in the outside of piezoceramics ring 3, receiving stick 1 is vertical to be fixed in the outside of overcoat 2.
Further defined, the polarization direction of the piezoelectric ceramic ring 3 is tangential to the circumference of the torus.
Further defined, the vector hydrophone is secured to the open end of the U-shaped base 5 by a liner rod 4.
Further, the outer electrode surface of the piezoelectric ceramic ring 3 is a signal output electrode, and the inner electrode surface of the piezoelectric ceramic ring 3 is a ground terminal.
Further defined, the material of the receiving rod 1 is an acoustically rigid material or a low-density composite material.
Further defined, the receiving rod 1 is made of a low-density composite material consisting of metal or glass beads and epoxy resin.
Further defined, the lining rod 4 and the base 5 are made of steel, copper or high-density alloy materials.
Further, the material of the jacket 2 is a low-density metal material such as an aluminum alloy.
Further defined, the inner struts 4 of a plurality of vector hydrophones are connected to form an array, the receiving bars 1 of adjacent vector hydrophones being parallel to each other, the distance between adjacent vector hydrophones being half a wavelength of the desired frequency.
Further defined, the inner struts 4 of a plurality of vector hydrophones are joined to form a two-dimensional vector hydrophone, the receiving bars 1 of adjacent vector hydrophones being perpendicular to each other, the distance between adjacent vector hydrophones being substantially less than the desired frequency wavelength.
The invention has the following beneficial effects: the invention applies the shearing motion of the piezoelectric ceramics to the non-inertial vector hydrophone for the first time, and utilizes d 15 The high piezoelectric parameters realize the high-sensitivity receiving of the non-inertial vector hydrophone under the condition of small volume, the non-inertial vector hydrophone does not need differential output, vector signals can be directly output, differential errors of the signals are eliminated, and meanwhile, the defect that the inertial vector hydrophone needs to be suspended is avoided.
Drawings
FIG. 1 is a schematic diagram of a vector hydrophone structure;
FIG. 2 is a schematic view of a tangentially-polarized piezoelectric ceramic ring;
FIG. 3 is a sensitivity profile of the vector hydrophone of example 1;
FIG. 4 is a directivity diagram of the vector hydrophone of example 1;
FIG. 5 is a diagram of a vector hydrophone array of example 2;
FIG. 6 is a block diagram of a two-dimensional vector hydrophone of example 3;
in the figure, the rod is received by a 1-receiving rod, a 2-outer sleeve, a 3-piezoelectric ceramic ring, a 4-lining rod, a 5-base, a 6-outer electrode surface and a 7-inner electrode surface.
Detailed Description
The present invention will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.
The experimental methods used in the following examples are conventional methods unless otherwise specified. The materials, reagents, methods and apparatus used, without any particular description, are those conventional in the art and are commercially available to those skilled in the art.
Example 1:
as shown in FIG. 1, the vector hydrophone comprises a receiving rod 1, an outer sleeve 2, a piezoelectric ceramic ring 3 and an inner lining rod 4, wherein the piezoelectric ceramic ring 3 is tightly sleeved on the inner lining rod 4, the outer sleeve 2 is tightly sleeved on the outer side of the piezoelectric ceramic ring 3, the receiving rod 1 is vertically fixed on the outer side of the outer sleeve 2, and the polarization direction of the piezoelectric ceramic ring 3 is the tangential direction of the circumference of a circular ring. So arranged, as shown in FIG. 2, the polarization direction of the piezoelectric ceramic ring 3 is tangential along the circumference, namely theta direction, when the receiving rod 1 is forced to move, the outer sleeve 2 closely connected with the receiving rod 1 moves relatively to the inner lining rod 4, so that the piezoelectric ceramic ring 3 generates torsion movement, the outer electrode surface 6 and the inner electrode surface 7 of the piezoelectric ceramic ring 3 generate potential difference, output charges, and the charge quantity S thereof q The method comprises the following steps:
S q ＝γF x d 15
wherein F is x In order to receive the sound pressure gradient force on the rod 1 along the X direction, gamma is the conversion coefficient of the force, d 15 Is a piezoelectric constant.
As shown in FIG. 1, when an underwater sound wave propagates along the XY plane, a sound pressure gradient force F is applied to the receiving rod 1 in the X direction x It can be found by integrating the sound pressure value at its surface:
wherein F is sound pressure gradient force, alpha is the included angle between the sound pressure gradient force and the X axis, and P o For incident sound pressure, P ff To receive the scattered sound pressure on the rod 1 s is the surface area of the receiving rod 1.
The voltage output is S v ＝S q /C 0 Wherein C 0 Is the static capacitance between the inner electrode and the outer electrode of the piezoelectric ceramic ring 3.
And because the sound pressure gradient force is proportional to the acceleration in water, namely F=βa, a is the acceleration of water particles, and β is a coefficient.
Thus, the vector hydrophone output voltage is proportional to the particle acceleration signal. Its sensitivity can be M p ＝S v /P o And (5) obtaining.
The vector hydrophone is secured to the open end of a U-shaped base 5 by a lining rod 4.
The receiving rod 1 is made of an acoustic rigid material, such as a low-density composite material formed by metal or glass beads and epoxy resin, and the receiving sensitivity of the vector hydrophone is mainly influenced by the height and the surface area of the receiving rod 1 and is insensitive to the material of the receiving rod 1, so that the receiving rod 1 is recommended to be made of the low-density composite material under the condition of strict quality requirements so as to reduce the overall quality of the vector hydrophone.
The lining rod 4 and the base 5 are made of steel, copper or high-density alloy materials. The material of the outer sleeve 2 is aluminum alloy.
The outer electrode surface 6 of the piezoelectric ceramic ring 3 is a signal output electrode and is connected with a signal output line, the inner electrode surface 7 of the piezoelectric ceramic ring 3 is a grounding end, and the signal line can be output from the outer sleeve 2 due to the close contact between the outer sleeve 2 and the outer electrode surface 6.
The sensitivity curve diagram and the directivity diagram of the vector hydrophone are shown in fig. 3 and 4 respectively, the sensitivity of the vector hydrophone is about-204.5 dB (at 1 kHz), and the slope characteristic of 6dB per octave is satisfied. The upper limit operating frequency can reach 3kHz. The directivity satisfies the cosine directivity characteristic of the 8-shaped character of the vector hydrophone.
Example 2:
the vector hydrophone of example 1 can only receive one-dimensional vector signals, and in order to increase its practical effectiveness, a plurality of vector hydrophones can be arranged in an array, and the lining rods 4 are directly connected by removing the base 5, as shown in fig. 5, the receiving rods 1 of adjacent vector hydrophones are parallel to each other, and the distance between the adjacent vector hydrophones is half a wavelength of the required frequency.
Example 3:
the vector hydrophone of embodiment 1 can only receive one-dimensional vector signals, and in order to increase the practical effectiveness, two vector hydrophones can be formed into a two-dimensional vector hydrophone, as shown in fig. 6, the receiving bars 1 of adjacent vector hydrophones are perpendicular to each other, and orthogonal dual-channel receiving can be performed.
The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, and alternatives falling within the spirit and principles of the invention.
Claims (7)
1. The torsion type non-inertial vector hydrophone is characterized by comprising a receiving rod (1), an outer sleeve (2), a piezoelectric ceramic ring (3) and an inner lining rod (4), wherein the piezoelectric ceramic ring (3) is tightly sleeved on the inner lining rod (4), the outer sleeve (2) is tightly sleeved on the outer side of the piezoelectric ceramic ring (3), and the receiving rod (1) is vertically fixed on the outer side of the outer sleeve (2); the polarization direction of the piezoelectric ceramic ring (3) is the tangential direction of the circumference of the circular ring;
the vector hydrophone is fixed at the opening end of a U-shaped base (5) through a lining rod (4);
the outer electrode surface of the piezoelectric ceramic ring (3) is a signal output electrode, and the inner electrode surface of the piezoelectric ceramic ring (3) is a grounding end;
the polarization direction of the piezoelectric ceramic ring (3) is tangential direction along the circumference, namely theta direction, when the receiving rod (1) is forced to move, the outer sleeve (2) tightly connected with the receiving rod (1) generates relative movement relative to the inner lining rod (4), so that the piezoelectric ceramic ring (3) generates torsion movement, the outer electrode surface (6) and the inner electrode surface (7) of the piezoelectric ceramic ring (3) generate potential difference, and output charges, the charge quantity of which isS q The method comprises the following steps:
S
q
=γF
x
d
15
wherein,F x in order to receive the sound pressure gradient force along the X direction on the rod (1),γas a transformation coefficient of the force,d 15 is a piezoelectric constant;
when the underwater sound wave propagates along the XY plane, the receiving rod (1) is subjected to sound pressure gradient force along the X directionF x It can be found by integrating the sound pressure value at its surface:
wherein the method comprises the steps ofFFor the acoustic pressure gradient force,αis the included angle between the sound pressure gradient force and the X axis,P o for the incident sound pressure,P ff to receive scattered sound pressure on the wand (1),sfor receiving the surface area of the rod (1);
the voltage output isS v =S q /C 0 WhereinC 0 Is a static capacitance between the inner electrode and the outer electrode of the piezoelectric ceramic ring (3);
due to the gradient force of sound pressure being proportional to the acceleration rate in water, i.eF=βa，aIs the acceleration of the water mass point,βis a coefficient;
therefore, the output voltage of the vector hydrophone is proportional to the particle acceleration signal, and the sensitivity is usedM p =S v /P o And (5) obtaining.
2. A torsional non-inertial vector hydrophone according to claim 1, characterized in that the receiving rod (1) is of acoustically rigid material.
3. The torsion type non-inertial vector hydrophone according to claim 2, wherein the receiving rod (1) is made of a composite material consisting of metal or glass beads and epoxy resin.
4. A torsion type non-inertial type vector hydrophone according to claim 1, characterized in that the lining rod (4) and the base (5) are made of steel, copper or high-density alloy material.
5. A torsion type non-inertial vector hydrophone according to claim 1, characterized in that the material of the outer jacket (2) is aluminium alloy.
6. A torsion-type non-inertial vector hydrophone according to claim 1, characterized in that the inner bars (4) of a plurality of vector hydrophones are connected to form an array, the receiving bars (1) of adjacent vector hydrophones being parallel to each other, the distance between adjacent vector hydrophones being half a wavelength of the desired frequency.
7. A torsion-type non-inertial type vector hydrophone according to claim 1, characterized in that the lining bars (4) of a plurality of vector hydrophones are connected to form a two-dimensional vector hydrophone, the receiving bars (1) of adjacent vector hydrophones are mutually perpendicular, and the distance between adjacent vector hydrophones is smaller than the wavelength of the operating frequency.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110818475.1A CN113639852B (en) | 2021-07-20 | 2021-07-20 | Torsion type non-inertial vector hydrophone |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110818475.1A CN113639852B (en) | 2021-07-20 | 2021-07-20 | Torsion type non-inertial vector hydrophone |
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| Publication Number | Publication Date |
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| CN113639852A CN113639852A (en) | 2021-11-12 |
| CN113639852B true CN113639852B (en) | 2024-01-02 |
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