CN112362154A - Sound pressure calibration method for hydrophone of long linear array cable - Google Patents
Sound pressure calibration method for hydrophone of long linear array cable Download PDFInfo
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- CN112362154A CN112362154A CN202011195212.1A CN202011195212A CN112362154A CN 112362154 A CN112362154 A CN 112362154A CN 202011195212 A CN202011195212 A CN 202011195212A CN 112362154 A CN112362154 A CN 112362154A
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- 238000000034 method Methods 0.000 title claims abstract description 28
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 33
- 239000010959 steel Substances 0.000 claims abstract description 33
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 17
- 238000005259 measurement Methods 0.000 claims abstract description 11
- 239000004677 Nylon Substances 0.000 claims abstract description 9
- 229920001778 nylon Polymers 0.000 claims abstract description 9
- 230000005855 radiation Effects 0.000 claims abstract description 7
- 238000009434 installation Methods 0.000 claims abstract description 5
- 230000035945 sensitivity Effects 0.000 claims description 17
- ZZUFCTLCJUWOSV-UHFFFAOYSA-N furosemide Chemical compound C1=C(Cl)C(S(=O)(=O)N)=CC(C(O)=O)=C1NCC1=CC=CO1 ZZUFCTLCJUWOSV-UHFFFAOYSA-N 0.000 claims description 9
- 238000012360 testing method Methods 0.000 claims description 9
- 238000003466 welding Methods 0.000 claims description 8
- 229910001220 stainless steel Inorganic materials 0.000 claims description 5
- 239000010935 stainless steel Substances 0.000 claims description 5
- 238000005452 bending Methods 0.000 description 2
- 230000005236 sound signal Effects 0.000 description 2
- 238000003491 array Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000013307 optical fiber Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01H—MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES
- G01H3/00—Measuring characteristics of vibrations by using a detector in a fluid
- G01H3/005—Testing or calibrating of detectors covered by the subgroups of G01H3/00
Abstract
The invention relates to the technical field of array cable hydrophone performance measurement, in particular to a long-linear array cable hydrophone sound pressure calibration method, which comprises the following steps: s1, coiling the long linear array cable on a hollowed measuring frame, coiling the long linear array cable according to a certain interval distance, and simultaneously keeping hydrophone array elements fixed at the relative positions of the array cable; s2, vertically suspending and fixing a low-frequency sound source on a hollowed-out measuring frame by using a nylon rope, tensioning the sound source by using the nylon rope in four circumferential directions to prevent the sound source from swinging back and forth and left and right, and enabling the circumferential radiation center of the sound source and the hydrophone array element to be measured to be located at the same horizontal position; s3, mounting a standard hydrophone at a position, which is a certain distance away from the sound source, on the hollow measuring frame, and enabling the standard hydrophone and the sound source to be located at the same horizontal position and not to swing; s4, hoisting the whole hollow measuring frame after the installation into water by using a steel cable; no matter the change of the posture of the underwater measuring frame, the influence of water flow and the deviation of depth are not influenced in the measuring process.
Description
Technical Field
The invention relates to the technical field of array cable hydrophone performance measurement, in particular to a long-linear array cable hydrophone sound pressure calibration method.
Background
At present, long linear arrays (piezoelectric hydrophone array cables and optical fiber hydrophone array cables) buried in the seabed in China are widely applied, and test tasks are frequent. The two long linear cables are both provided with key components, namely acoustic hydrophones, so that each cable needs to be subjected to acoustic performance testing, each cable is long, a receiving array element hydrophone array element is arranged every x meters, one array cable is generally 16 elements in total, and the length of the cable is more than dozens of meters. The guide cable frame is generally applied to guide array cables to enter water vertically in the industry at present, a hydrophone array element enters water in sequence to measure the receiving sensitivity when the hydrophone array element enters the water to a certain depth, the method for measuring the sound pressure sensitivity of the hydrophone is simple, time and labor are wasted, the posture of the underwater array cables is changed, the influence of water flow and the deviation of the depth have great influence on measurement data, and therefore the problem is solved by researching and developing a long-linear array cable hydrophone sound pressure calibration method urgently.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides a sound pressure calibration method for a hydrophone of a long linear array cable, and by the test method, the array cable, a sound source and a standard hydrophone form a whole, so that the equipment is convenient to hang and install; no matter the change of the posture of the underwater measuring frame, the influence of water flow and the deviation of depth are not influenced in the measuring process.
The invention is realized by the following technical scheme:
a sound pressure calibration method for a long linear array cable hydrophone comprises the following steps:
s1, coiling the long linear array cable on a hollowed measuring frame, coiling the long linear array cable according to a certain interval distance, and simultaneously keeping hydrophone array elements fixed at the relative positions of the array cable;
s2, vertically suspending and fixing a low-frequency sound source on a hollowed-out measuring frame by using a nylon rope, tensioning the sound source by using the nylon rope in four circumferential directions to prevent the sound source from swinging back and forth and left and right, and enabling the circumferential radiation center of the sound source and the hydrophone array element to be measured to be located at the same horizontal position;
s3, mounting a standard hydrophone at a position, which is a certain distance away from the sound source, on the hollow measuring frame, and enabling the standard hydrophone and the sound source to be located at the same horizontal position and not to swing;
s4, hoisting the whole hollow measuring frame after the installation into water by using a steel cable, and then sequentially measuring the sensitivity of each measured hydrophone array element; the method comprises the following specific steps:
and starting to test when the underwater depth reaches 10m, transmitting signals by a sound source, simultaneously receiving signals by the standard hydrophones and the hydrophone array elements on the array cable, demodulating the signals of the hydrophone array elements on the array cable, and comparing the demodulated signals with the sound pressure of the standard hydrophone signals to obtain the receiving sensitivity value of the hydrophone array elements on the array cable.
Preferably, the hollowed-out measuring rack in the step S1 is manufactured by the following steps:
1) selecting 2 stainless steel pipes, bending and welding the stainless steel pipes into a disc shape, wherein the diameter of each selected steel pipe is 50mm, and the diameter of each disc-shaped steel pipe is 2 m;
2) select for use 8 piece at least channel-section steels and the discoid steel pipe welding that is located both sides, and make the welding point circumference of channel-section steel and discoid steel pipe distribute on discoid steel pipe for the holistic length of fretwork measuring frame is 2.5 m.
Preferably, the number of the hydrophone array elements fixed at the respective opposite positions of the array cable in the step S1 is at least 16, and the hydrophone array elements are symmetrically distributed at the same horizontal position left and right and front and back by the center of the hollow measuring frame.
Preferably, the distance between the sound source and the standard hydrophone in the step S3 is 80 cm.
Preferably, in step S3, the sound source is vertically suspended at the center of the hollow measuring rack, the radiation surface of the sound source is kept facing the bottom of the lake, and the hydrophone array elements to be measured are distributed in parallel at two sides of the sound source.
Preferably, in the step S4, two end portions of the steel cable are connected to intersections of the disc-shaped steel pipes on two sides of the vertical shaft section of the hollow measuring rack, so that the hollow measuring rack after being installed can be vertically hoisted into water.
Preferably, in the step S4, when the sensitivity of the hydrophone array element to be measured is calculated, the measurement distances between the sound source and the standard hydrophone and between the sound source and the hydrophone array element to be measured are sequentially substituted into the calculation formula of the sensitivity of the hydrophone array element to be measured before the underwater measurement.
The invention has the beneficial effects that:
by the testing method, the array cable, the sound source and the standard hydrophone form a whole, and the equipment is convenient to hang and install; when the underwater measuring rack works, no matter the posture of the underwater measuring rack is changed, the influence of water flow and the deviation of depth are not influenced on the measuring process; the array cable disc is stable and reliable after being fixed on the measuring frame, the distance between a sound source and a standard hydrophone and the distance between the sound source and an array element to be measured are measured in sequence before underwater measurement, and the distance is substituted into a calculation formula when the sensitivity of the array element to be measured is calculated;
the hollowed-out measuring frame related in the testing method has the advantages of simple and novel structure, reasonable design, low manufacturing cost, convenience in use and strong practicability.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is a top view of the overall structure of the hollow measuring rack after the installation of the hollow measuring rack is completed.
In the figure: 10-disc-shaped steel pipe, 20-channel steel, 30-standard hydrophone, 40-hydrophone array element, 50-sound source, 60-array cable and 70-cross point.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The first embodiment is as follows:
a sound pressure calibration method for a long linear array cable hydrophone comprises the following steps:
s1, coiling the long linear array cable 60 on a hollowed measuring frame, coiling the long linear array cable on the hollowed measuring frame at certain intervals, and simultaneously keeping the hydrophone array elements 40 fixed on the array cable 60 at the relative positions;
s2, vertically suspending and fixing the low-frequency sound source 50 on a hollowed-out measuring frame by using a nylon rope, tensioning the sound source 50 by using the nylon rope in four directions of the circumference to prevent the sound source 50 from swinging back and forth and left and right, and enabling the circumferential radiation center of the sound source 50 and the hydrophone array element 40 to be measured to be located at the same horizontal position;
s3, installing a standard hydrophone 30 on the hollow measuring frame at a certain distance from the sound source 50, and enabling the standard hydrophone 30 and the sound source 50 to be located at the same horizontal position and not to swing;
s4, hoisting the whole hollow measuring frame after the installation into water by using a steel cable, and then sequentially measuring the sensitivity of each measured hydrophone array element 40; the method comprises the following specific steps:
and starting to test when the underwater depth reaches 10m, wherein the sound source 50 emits signals, the standard hydrophones 30 and the hydrophone array elements 40 on the array cable 60 simultaneously receive the signals, and the signals of the hydrophone array elements 40 on the array cable 60 are demodulated and then compared with the signals of the standard hydrophones 30 in sound pressure, so that the receiving sensitivity value of the hydrophone array elements 40 on the array cable 60 is obtained.
Specifically, the hollowed-out measuring rack in the step S1 is manufactured by the following steps:
1) selecting 2 stainless steel pipes, bending and welding the stainless steel pipes into a disc shape, wherein the diameter of each selected steel pipe is 50mm, and the diameter of each disc-shaped steel pipe 10 is 2 m;
2) select for use 8 at least channel-section steels 20 and be located the welding of the discoid steel pipe 10 of both sides, and make the welding point circumference of channel-section steel 20 and discoid steel pipe 10 distribute on discoid steel pipe 10 for the holistic length of fretwork measuring rack is 2.5 m.
Specifically, in step S1, the number of the hydrophone array elements 40 fixed at the respective opposite positions of the array cable 60 is at least 16, and the hydrophone array elements 40 are symmetrically distributed at the same horizontal position left and right and front and back with respect to the center of the hollow measuring frame.
Specifically, the distance between the sound source 50 and the standard hydrophone 30 in step S3 is 80 cm.
Specifically, in step S3, the sound source 50 is vertically suspended at the center of the hollow measuring rack, the radiation surface of the sound source 50 is kept facing the bottom of the lake, and the hydrophone array elements 40 to be measured are distributed in parallel at two sides of the sound source 50.
Specifically, in step S4, the two ends of the wire rope are connected to the intersections 70 of the two disc-shaped steel pipes 10 on the vertical axis of the hollow measuring rack, so that the hollow measuring rack can be vertically lifted into water.
Specifically, in step S4, when the sensitivity of the hydrophone array element 40 to be measured is calculated, the measurement distances between the sound source 50 and the standard hydrophone 30 and between the sound source 50 and the hydrophone array element 40 to be measured are sequentially substituted into the calculation formula for the sensitivity of the hydrophone array element 40 to be measured before the underwater measurement.
The working principle is as follows: when the device is used, the long-line array cable 60 is wound on the hollow measuring frame, and then the hydrophone array elements 40 on the array cable 60 are aligned to the sound source 50 in height and horizontal position, the sound source 50 is vertically suspended by nylon ropes, and the circumference is tensioned by ropes in four directions without swinging left and right; a standard hydrophone 30 is arranged at a position 50 away from the sound source 50 by 80cm, and the same height with the sound source 50 is ensured not to swing; after the array cable 60 is completely installed, the hollow measuring frame is integrally hoisted into water by using a steel cable, the hollow measuring frame generally enters about 10m of water to start testing work, the sound source 50 emits sound signals, the standard hydrophone 30 and the hydrophone array elements 40 on the array cable 60 simultaneously receive the sound signals, and the signals of the hydrophone array elements 40 on the array cable 60 are demodulated and then compared with the signals of the standard hydrophone 30 to obtain the receiving sensitivity value of the hydrophone array elements 40 on the array cable 60;
by the testing method, the array cable 60, the sound source 50 and the standard hydrophone 30 are integrated, so that the equipment is convenient to hang and install; when the underwater measuring rack works, no matter the posture of the underwater measuring rack is changed, the influence of water flow and the deviation of depth are not influenced on the measuring process; the array cable 60 disc is fixed on the hollow measuring frame stably and reliably, the distance between the sound source 50 and the standard hydrophone 30 and the distance between the sound source 50 and the measured hydrophone array element 40 are measured in sequence before underwater measurement, and the distances are substituted into a calculation formula when the sensitivity of the measured array element is calculated.
The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.
Claims (7)
1. A sound pressure calibration method for a long linear array cable hydrophone is characterized by comprising the following steps:
s1, coiling the long linear array cable on a hollowed measuring frame, coiling the long linear array cable according to a certain interval distance, and simultaneously keeping hydrophone array elements fixed at the relative positions of the array cable;
s2, vertically suspending and fixing a low-frequency sound source on a hollowed-out measuring frame by using a nylon rope, tensioning the sound source by using the nylon rope in four circumferential directions to prevent the sound source from swinging back and forth and left and right, and enabling the circumferential radiation center of the sound source and the hydrophone array element to be measured to be located at the same horizontal position;
s3, mounting a standard hydrophone at a position, which is a certain distance away from the sound source, on the hollow measuring frame, and enabling the standard hydrophone and the sound source to be located at the same horizontal position and not to swing;
s4, hoisting the whole hollow measuring frame after the installation into water by using a steel cable, and then sequentially measuring the sensitivity of each measured hydrophone array element; the method comprises the following specific steps:
and starting to test when the underwater depth reaches 10m, transmitting signals by a sound source, simultaneously receiving signals by the standard hydrophones and the hydrophone array elements on the array cable, demodulating the signals of the hydrophone array elements on the array cable, and comparing the demodulated signals with the sound pressure of the standard hydrophone signals to obtain the receiving sensitivity value of the hydrophone array elements on the array cable.
2. The sound pressure calibration method for the long-linear array cable hydrophone according to claim 1, wherein the hollowed-out measuring frame in the step S1 is manufactured by the following steps:
2 stainless steel pipes are selected and bent to be welded into a disc shape, the diameter of each selected steel pipe is 50mm, and the diameter of each disc-shaped steel pipe is 2 m;
choose for use 8 at least channel-section steels and the discoid steel tube welding who is located both sides, and make the welding point circumference of channel-section steel and discoid steel pipe distribute on discoid steel pipe for the holistic length of fretwork measuring frame is 2.5 m.
3. The sound pressure calibration method for the long-linear array cable hydrophone according to claim 1, wherein the sound pressure calibration method comprises the following steps: in the step S1, the number of the hydrophone array elements fixed at the respective relative positions of the array cable is at least 16, and the hydrophone array elements are symmetrically distributed at the same horizontal position left and right and front and back by the center of the hollow measuring frame.
4. The sound pressure calibration method for the long-linear array cable hydrophone according to claim 1, wherein the sound pressure calibration method comprises the following steps: in the step S3, the distance between the sound source and the standard hydrophone is 80 cm.
5. The sound pressure calibration method for the long-linear array cable hydrophone according to claim 1, wherein the sound pressure calibration method comprises the following steps: and S3, the sound source is vertically hung at the center of the hollowed-out measuring frame, the radiation surface of the sound source faces the bottom of the lake, and the hydrophone array elements to be measured are distributed on two sides of the sound source in parallel.
6. The sound pressure calibration method for the long-linear array cable hydrophone according to claim 1, wherein the sound pressure calibration method comprises the following steps: and S4, connecting the two ends of the steel cable with the cross points of the disc-shaped steel pipes on the two sides of the vertical shaft section of the hollow measuring frame, so that the hollow measuring frame can be integrally vertically hoisted into water.
7. The sound pressure calibration method for the long-linear array cable hydrophone according to claim 1, wherein the sound pressure calibration method comprises the following steps: in the step S4, when the sensitivity of the hydrophone array element to be measured is calculated, the measurement distances between the sound source and the standard hydrophone and between the sound source and the hydrophone array element to be measured before the underwater measurement are sequentially substituted into the calculation formula of the sensitivity of the hydrophone array element to be measured.
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| CN202011195212.1A CN112362154A (en) | 2020-10-30 | 2020-10-30 | Sound pressure calibration method for hydrophone of long linear array cable |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113238233A (en) * | 2021-04-12 | 2021-08-10 | 中船重工海声科技有限公司 | Device and method for quickly measuring sensitivity of long linear array element based on underwater camera |
| CN114018396A (en) * | 2021-10-22 | 2022-02-08 | 中国舰船研究设计中心 | Low-frequency underwater sound measurement system and layout method |
| CN114018397A (en) * | 2021-10-28 | 2022-02-08 | 中国舰船研究设计中心 | Hydrophone arc linear array low-frequency calibration device and calibration method thereof |
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