Round tube hydrophone radial acceleration sensitivity measuring device and measuring method

Abstract

The invention relates to a device and a method for measuring the radial acceleration sensitivity of a circular tube hydrophone. The device comprises a base, a hasm, an end cover, a to-be-measured circular tube hydrophone, a sliding block, a preamplifier, an accelerometer and a vibration exciter, wherein a plurality of mounting holes with different sizes are formed in the bottom of the base, so that vibration exciters with different interfaces can be mounted in a matched manner; the top of the base is a semicircular pipe with a semicircular cross section, the semicircular pipe is horizontally arranged, two sliding grooves are formed in the inner wall of the semicircular pipe in the length direction of the semicircular pipe, a plurality of sliding blocks are connected in each sliding groove in a sliding mode, the inner end faces of the sliding blocks are conformal with the sliding grooves, the outer end faces of the sliding blocks are in an arc shape, and the size of each sliding block is matched with the outer diameter of the circular tube hydrophone to be measured. On the basis that an accelerometer method is used for testing, through the structural integrated design of the hydrophone and the pre-amplification circuit, and the signal transmission process is in an electromagnetic shielding environment, design defects existing in an existing scheme are effectively avoided.

Description

Technical field:

[0001] The invention belongs to the technical field of hydrophone detection, and relates to a device and a method for measuring radial acceleration sensitivity of a circular tube hydrophone. Background technology:

[0002] The circular tube hydrophone is an ideal choice for towed array systems due to its high sensitivity and wide-band response characteristics. However, it will be disturbed by axial and radial vibration signals during the acoustic detection process. Therefore, acceleration sensitivity is one of the important performance indicators of the circular tube hydrophone, which can reflect the response characteristics of the hydrophone when subjected to acceleration. Therefore, measuring the acceleration sensitivity of the hydrophone is crucial to evaluating its performance in water.

[0003] Most of the existing test devices are only suitable for circular tube hydrophones of specific sizes and have a single structure. During testing, the preamplifier circuit is generally placed on the outside, and the electromagnetic shielding effect is relatively poor. The test process will be affected by the superposition of multiple interference factors, and the data consistency is poor. Summary of the invention:

[0004] The technical problem to be solved by the present invention is to provide a device and method for measuring the radial acceleration sensitivity of a circular tube hydrophone. Based on the test using the accelerometer method, the hydrophone and the preamplifier circuit are designed to be structurally integrated, and the signal transmission process is in an electromagnetic shielding environment, which effectively avoids the design drawbacks of the existing scheme.

[0005] The technical solution of the present invention is to provide a circular tube hydrophone radial acceleration sensitivity measurement device, comprising a base, a Hafu, an end cover, a circular tube hydrophone to be measured, a slider, a preamplifier, an accelerometer and an exciter; wherein,

[0006] The bottom of the base is provided with a number of mounting holes of different sizes to match the installation of exciters with different interfaces; the top of the base is a semicircular tube with a semicircular cross section, the semicircular tube is arranged horizontally, and the inner wall of the semicircular tube is provided with two slide grooves along the length direction of the semicircular tube, and a plurality of sliders are slidably connected in each slide groove, and the inner end faces of the sliders are respectively conformal to the slide grooves, and the outer end faces of the sliders are arc-shaped, and the size is adapted to the outer diameter of the circular tube hydrophone to be tested, and the sliders are also provided with countersunk holes, and screws are threadedly connected in the countersunk holes. After determining the clamping position of the circular tube hydrophone to be tested, the sliders can be tightened in the corresponding slide grooves by screws;

[0007] The Hafu is a semi-circular tube structure and its diameter is adapted to the semi-circular tube of the base. The Hafu and the semi-circular tube are assembled into a cylinder. The inner wall of the Hafu is provided with a second slide groove arranged along the length direction of the Hafu. The second slide groove is slidably connected with a second slider. The second slider has the same structure as the slider on the semi-circular tube. After the clamping position of the circular tube hydrophone to be tested is determined, the second slider can be fastened in the second slide groove by screws;

[0008] The diameter of the end cap is adapted to the outer diameter of the semicircular tube, and the end cap closes both ends of the cylinder through fasteners;

[0009] The circular tube hydrophone to be tested is integrally cast and is clamped in a cylinder composed of a Hafu and a semicircular tube by the cooperation of a slider and a second slider;

[0010] The preamplifier is encapsulated in a metal shell on the outside and contains a preamplifier circuit on the inside. The preamplifier is fixed in the cylinder. The lead wire of the circular tube hydrophone to be tested is connected to the input end of the preamplifier. The lead wire from the output end of the preamplifier passes through the end cover and extends outward.

[0011] The vibrator is installed on the mounting hole of the base;

[0012] The accelerometer is connected to the vibrator to ensure that the circular tube hydrophone to be tested and the accelerometer maintain the same amplitude during vibration;

[0013] The base, Hafu and end caps are all made of metal.

[0014] The present invention is based on the accelerometer method test and can adapt to circular tube hydrophones of different sizes through reasonable structural design. The preamplifier is placed in the metal cavity to ensure that the acceleration response signal output process is inside the shielding layer. The structure is simple and the test is stable, which can effectively avoid the design defects existing in the existing scheme.

[0015] Preferably, the semicircular tube and the Hafu are assembled into a cylinder and then fastened with screws.

[0016] Preferably, the two slide grooves and the second slide groove in the cylinder are evenly distributed along the circumferential direction.

[0017] Preferably, the diameter and size of the circular tube hydrophone to be tested are designed according to the working frequency band and the impedance matching characteristics of the preamplifier circuit.

[0018] Preferably, the base, Hafu and end cover are made of aluminum alloy.

[0019] Preferably, the preamplifier circuit operates in a frequency band of 10 Hz to 10 kHz, outputs in a differential form, and has an amplification of 40 dB.

[0020] Preferably, the sensitivity of the accelerometer 7 is 100 mv / g.

[0021] Preferably, when the accelerometer is in use, one side is connected to an accelerometer power supply, and the analog signal is connected to an oscilloscope.

[0022] Preferably, the dimension of the connection between the bottom upper plane of the base and the outer arc of the semicircular tube at the top is no greater than 5 cm.

[0023] The present invention also provides a measuring method for the radial acceleration sensitivity measuring device of the circular tube hydrophone as described above, wherein the accelerometer and the bottom of the base are fixed on the table of the exciter, the radial direction of the circular tube hydrophone to be measured is kept consistent with the vibration direction of the exciter, and the radial vibration acceleration borne by the circular tube hydrophone to be measured is measured by the accelerometer; the circular tube hydrophone to be measured and the accelerometer are powered by a low-voltage power supply and an accelerometer power supply respectively, the exciter keeps vibrating in a vertical direction, a sinusoidal signal of a specific frequency is emitted by a signal source and amplified by a power amplifier and then transmitted to the exciter; then the circular tube hydrophone to be measured converts the acquired sound pressure information into an electrical signal, and inputs it into a preamplifier and a filter for further processing, and the processed voltage peak-to-peak value U of the circular tube hydrophone to be measured and the accelerometer is converted into an electrical signal. H with U a The open-circuit voltage at the output is displayed on the oscilloscope; finally, the radial acceleration sensitivity M of the hydrophone can be obtained according to formula (1): a :

[0024]

[0025] Where M ar is the sensitivity of a standard accelerometer.

[0026] Compared with the prior art, the present invention has the following advantages:

[0027] The present invention adopts the accelerometer method to measure the radial acceleration sensitivity of the component to be tested. Under the premise of simulating the acceleration environment, the hydrophone to be tested and the preamplifier circuit are placed in the same electromagnetic shielding environment. The device itself is made of all-metal material, so that the test process can avoid the introduction of unnecessary interference and vibration loss. At the same time, the device can change the shape and clamping position of the fixture according to the different sizes of circular tube hydrophones, thereby improving the overall flexibility of the device. Description of the drawings:

[0028] Figure 1 It is a schematic diagram of the local structure of the present invention;

[0029] Figure 2 It is a schematic diagram of the device of the present invention when in use;

[0030] Figure 3 This is a measurement principle diagram of the present invention. Specific implementation method:

[0031] The present invention will be further described below with reference to the accompanying drawings:

[0032] The circular tube hydrophone radial acceleration sensitivity measuring device of the present invention mainly comprises a base 1, a circular tube hydrophone to be measured 2, a preamplifier 3, a slider 4, a Hafu 5, an end cover 6, an exciter 7, and an accelerometer 8.

[0033] like Figure 1 , 2 In this embodiment, the base 1 is made of aluminum alloy. Several through holes are provided at the bottom of the base 1, and the vibrator 7 is connected through the through holes that match the interface specifications. The top of the base 1 is a semicircular tube, which is arranged horizontally. Two slide grooves are provided on the inner wall of the semicircular tube along the length direction of the semicircular tube. Multiple sliders 4 are slidably connected in each slide groove. The slider 4 is fan-shaped as a whole, and the inner end faces of the slider 4 are respectively conformal to the slide grooves. The outer end faces of the sliders are arc-shaped, and the size is adapted to the outer diameter of the circular tube hydrophone 2 to be tested. There is also a countersunk hole in the middle of the slider 4, and a screw is threaded in the countersunk hole. After determining the clamping position of the circular tube hydrophone 2 to be tested, the slider 4 can be tightened in the corresponding slide groove by screws. The cross section of the semicircular tube is provided with 4 threaded holes to be tightened with the Hafu 5 by screws; the left and right end faces of the semicircular tube are each provided with 2 threads to connect the end cover 6. When installed and used, the radial direction of the circular tube hydrophone 2 to be tested is consistent with the vibration direction of the vibrator 7.

[0034] In this embodiment, Hafu 5 is made of aluminum alloy. The whole is in the shape of a semicircular tube. A second slide groove is provided on the inner wall of Hafu, and a slider 4 is slidably installed in the second slide groove. The second slider has the same structure as the slider on the semicircular tube. After the clamping position of the circular tube hydrophone to be tested is determined, the second slider can be fastened in the second slide groove by screws, and the circular tube hydrophone to be tested can be clamped and positioned in cooperation with the slider on the semicircular tube; the cross section of Hafu 5 has 4 through holes, which are fixed to the base 1 by screws; a lead groove is provided at the top left side of Hafu 5 to lead out the wires of the preamplifier 3.

[0035] In this embodiment, the end cap 6 is made of aluminum alloy. The whole is cylindrical, and its appearance is consistent with the cross section of the cylinder after the semicircular tube and the Hafu 5 are assembled. Two through holes are opened on the surface and fixed to the two ends of the cylinder by screws, so that the inside of the device forms a closed environment.

[0036] In this embodiment, the circular tube hydrophone 2 to be tested is integrally molded by injection molding. The diameter and size of the circular tube hydrophone 2 to be tested are designed according to the working frequency band and the impedance matching characteristics of the preamplifier circuit. When in use, it is hard-connected to the base 1 and the inside of the Hafu 5. The base 1 and the Hafu 5 are both made of metal materials, and the internal shielding environment is formed to avoid the introduction of external electromagnetic interference. There are 2 pins on the upper end surface of the component, namely the positive and negative poles of the circular tube hydrophone 2 to be tested, which are connected to the input end of the preamplifier 3.

[0037] In this embodiment, the preamplifier 3 is encapsulated in a metal shell, and the preamplifier circuit is inside, and the preamplifier circuit is connected through pins. The preamplifier circuit has an operating frequency band of 10Hz to 10kHz, outputs in a differential form, and has an amplification of 40dB.

[0038] In this embodiment, the sensitivity of the accelerometer 8 is 100mv / g. The accelerometer 8 is hard-connected to the exciter 7 to ensure that the hydrophone to be tested and the accelerometer maintain the same amplitude during vibration. When in use, one side is connected to the accelerometer power supply, and the analog signal is connected to the oscilloscope.

[0039] The measurement principle diagram used in the present invention is as follows Figure 3 The measurement system includes a signal source, a power amplifier, a component to be tested, an accelerometer, an exciter, a filter, an oscilloscope, an accelerometer power supply, a low-voltage power supply for a hydrophone, etc. The accelerometer and the bottom of the base are fixed on the table of the exciter, and the radial direction of the circular tube hydrophone to be tested is kept consistent with the vibration direction of the exciter. The accelerometer is used to measure the radial vibration acceleration of the circular tube hydrophone to be tested; the circular tube hydrophone to be tested and the accelerometer are powered by the low-voltage power supply and the accelerometer power supply respectively, and the exciter keeps vibrating in the vertical direction. A sinusoidal signal of a specific frequency is emitted by the signal source and amplified by the power amplifier and then transmitted to the exciter; the circular tube hydrophone to be tested then converts the acquired sound pressure information into an electrical signal, and inputs it into the preamplifier and the filter for further processing, and the peak-to-peak value U of the processed circular tube hydrophone to be tested and the accelerometer is converted into an electrical signal. H with U a The open-circuit voltage at the output is displayed on the oscilloscope; finally, the radial acceleration sensitivity M of the hydrophone can be obtained according to formula (1): a :

[0040]

[0041] Where M ar is the sensitivity of a standard accelerometer.

[0042] The present invention characterizes the radial acceleration sensitivity of the hydrophone element through structural design, and the hydrophone and the exciter are hard-connected to ensure lossless vibration transmission. The preamplifier circuit is also placed in an electromagnetic shielding environment to avoid introducing unnecessary interference. In this way, the radial acceleration response capability of the circular tube hydrophone at different frequencies can be accurately compared, and the test results provide data reference for the performance evaluation of the hydrophone.

[0043] The above is only an explanation of the preferred embodiments of the present invention, which should not be construed as a limitation on the claims. Any equivalent process changes made using the present invention specification are included in the patent protection scope of the present invention.

Claims

1. A device for measuring radial acceleration sensitivity of a circular tube hydrophone, characterized in that: It includes a base, Hafu, end cover, a circular tube hydrophone to be tested, a slider, a preamplifier, an accelerometer and an exciter; among which, The bottom of the base is provided with a number of mounting holes of different sizes to match the installation of exciters with different interfaces; the top of the base is a semicircular tube, which is arranged horizontally, and the inner wall of the semicircular tube is provided with two slide grooves along the length direction of the semicircular tube, and a plurality of sliders are slidably connected in each slide groove, and the inner end faces of the sliders are respectively conformal to the slide grooves, and the outer end faces of the sliders are arc-shaped, and the size is adapted to the outer diameter of the circular tube hydrophone to be tested, and the sliders are also provided with countersunk holes, and screws are threadedly connected in the countersunk holes. After determining the clamping position of the circular tube hydrophone to be tested, the sliders can be tightened in the corresponding slide grooves by screws; The Hafu is a semi-circular tube structure and its diameter is adapted to the semi-circular tube of the base. The Hafu and the semi-circular tube are assembled into a cylinder. The inner wall of the Hafu is provided with a second slide groove arranged along the length direction of the Hafu. The second slide groove is slidably connected with a second slider. The second slider has the same structure as the slider on the semi-circular tube. After the clamping position of the circular tube hydrophone to be tested is determined, the second slider can be fastened in the second slide groove by screws; The diameter of the end cap is adapted to the outer diameter of the semicircular tube, and the end cap closes both ends of the cylinder through fasteners; The circular tube hydrophone to be tested is integrally cast and is clamped in a cylinder composed of a Hafu and a semicircular tube by the cooperation of a slider and a second slider; The preamplifier is encapsulated in a metal shell on the outside and contains a preamplifier circuit on the inside. The preamplifier is fixed in the cylinder. The lead wire of the circular tube hydrophone to be tested is connected to the input end of the preamplifier. The lead wire from the output end of the preamplifier passes through the end cover and extends outward. The vibrator is installed on the mounting hole of the base; The accelerometer is connected to the vibrator to ensure that the circular tube hydrophone to be tested and the accelerometer maintain the same amplitude during vibration; The base, Hafu and end caps are all made of metal.

2. The circular tube hydrophone radial acceleration sensitivity measuring device according to claim 1, characterized in that: The semicircular tube and the Hafu are assembled into a cylinder and then fastened with screws.

3. The circular tube hydrophone radial acceleration sensitivity measuring device according to claim 2, characterized in that: The chute and the second chute in the cylinder are evenly distributed along the circumferential direction.

4. The circular tube hydrophone radial acceleration sensitivity measuring device according to claim 1, characterized in that: The diameter and size of the circular tube hydrophone to be tested are designed according to the working frequency band and the impedance matching characteristics of the preamplifier circuit.

5. The circular tube hydrophone radial acceleration sensitivity measuring device according to claim 1, characterized in that: The base, Hafu and end cover are made of aluminum alloy.

6. The circular tube hydrophone radial acceleration sensitivity measuring device according to claim 1, characterized in that: The operating frequency band of the preamplifier circuit is 10Hz~10kHz, and the output is in differential form with an amplification of 40dB.

7. The circular tube hydrophone radial acceleration sensitivity measuring device according to claim 1, characterized in that: The sensitivity of the accelerometer 7 is 100 mv / g.

8. The device for measuring radial acceleration sensitivity of a circular tube hydrophone according to claim 7, characterized in that: When the accelerometer is in use, one side is connected to the accelerometer power supply and the analog signal is connected to the oscilloscope.

9. The circular tube hydrophone radial acceleration sensitivity measuring device according to claim 1, characterized in that: The size of the connection between the upper plane of the bottom of the base and the outer arc of the semicircular tube at the top is no more than 5cm.

10. The measuring method of the circular tube hydrophone radial acceleration sensitivity measuring device according to any one of claims 1 to 9, characterized in that: The accelerometer and the bottom of the base are fixed on the table of the exciter, the radial direction of the circular tube hydrophone to be tested is kept consistent with the vibration direction of the exciter, and the radial vibration acceleration of the circular tube hydrophone to be tested is measured by the accelerometer; the circular tube hydrophone to be tested and the accelerometer are powered by a low-voltage power supply and an accelerometer power supply respectively, the exciter keeps vibrating in the vertical direction, and a sinusoidal signal of a specific frequency is emitted by the signal source and amplified by a power amplifier and then transmitted to the exciter; then the circular tube hydrophone to be tested converts the acquired sound pressure information into an electrical signal, and inputs it into a preamplifier and a filter for further processing, and the peak-to-peak value U of the processed circular tube hydrophone to be tested and the accelerometer is converted into an electrical signal. H with U a The open-circuit voltage at the output is displayed on the oscilloscope; finally, the radial acceleration sensitivity M of the hydrophone can be obtained according to formula (1): a : Where M ar is the sensitivity of a standard accelerometer.

Images