Small-diameter precise short-element-spacing close-packed array

Abstract

The invention relates to the technical field of optical fiber sensing, and provides a small-diameter precise short-element spacing close-packed array which comprises a PU tube, a plurality of probe skeletons and a plurality of delay skeletons, the probe skeletons and the delay skeletons are arranged in the PU tube in an array mode, hydrophone probes are arranged in the probe skeletons, delay ring assemblies and optical devices are arranged in the delay skeletons, and the optical devices are arranged in the PU tube in an array mode. The outer diameter of the probe framework and the outer diameter of the delay framework are both 22.2 mm; the distance between the probe framework and the time delay framework is 45mm, the length of the time delay framework is 100mm, the length of the probe framework is 60mm, and the distance between two adjacent hydrophone probes is 250mm. The outer diameter phi of the array is 27mm, the space between elements is 0.25 m, internal structural parts are densely arranged, and the internal structural design is reasonably optimized and arranged; meanwhile, the delay ring framework is specially designed, the requirement for placing the delay ring can be met, the effects of placing optical devices and storing welding points and redundant optical fibers can be achieved, and finally a small-diameter precise short-element-interval close-packed array is formed.

Description

Technical Field

[0001] The present application belongs to the field of optical fiber sensing technology, and more specifically, relates to a small-diameter precision short-element close-packed array. Background Art

[0002] Fiber optic hydrophone is a new type of underwater acoustic sensor based on optical fiber and optoelectronic technology. It has the characteristics of high sensitivity, wide response bandwidth, resistance to electromagnetic interference, resistance to harsh environment, flexible structure, easy telemetry and large-scale array formation.

[0003] Existing submarine broadside sonar utilizes the side of the hull to increase the aperture of the array sonar, increase spatial gain, and improve sonar detection performance. The array aperture is 30 to 40 meters; the operating frequency of the hydrophone array detection is 100Hz-1500Hz; and the sensitivity is not high.

[0004] Based on the complex environment of the sea and the detection needs, the current development trends of submarine side hydrophone arrays are mainly as follows: towards high sensitivity, good very low frequency response, wide response bandwidth, large dynamic range and miniaturization. Summary of the invention

[0005] In view of the main development trend of how to realize the submarine side hydrophone array in the above-mentioned prior art, the purpose of the embodiments of the present application is to provide a small-diameter, precise, short-element-spacing, closely-packed side hydrophone array with high reliability, mass production and feasibility.

[0006] To achieve the above-mentioned purpose, the technical solution adopted in the present application is: to provide a small-diameter precision short-element spacing closely packed array, including: a PU tube, a probe skeleton and a delay ring skeleton, wherein the probe skeleton and the delay skeleton are arranged in an array in the PU tube in multiple numbers, a hydrophone probe is arranged in the probe skeleton, a delay ring assembly and an optical device are arranged in the delay skeleton, and the outer diameters of the probe skeleton and the delay skeleton are both 22.2mm; the spacing between the probe skeleton and the delay skeleton is 45mm, the length of the delay skeleton is 100mm, the length of the probe skeleton is 60mm, and the spacing between two adjacent hydrophone probes is 250mm.

[0007] In one embodiment, the inner diameter of the PU tube is 22 mm and the wall thickness is 2.5 mm.

[0008] In one embodiment, a first cavity and a second cavity are provided in the delay skeleton, the delay ring group is arranged in the first cavity, and the optical device is arranged in the second cavity.

[0009] In one embodiment, the time-delay frame includes an upper shell and a lower shell, and the upper shell and the lower shell are fixed by a plurality of screws.

[0010] In one embodiment, a core plugging assembly is provided at one end of the PU tube, and the transmission cable is sealed and inserted into the PU tube through the core plugging assembly. A fiber collecting skeleton assembly is provided between the core plugging assembly and the first probe skeleton, and a wavelength division multiplexer and an optical fiber coupler are provided in the fiber collecting skeleton assembly.

[0011] In one embodiment, the transmission cable is an eight-color tight-buffered optical fiber, and every two colors of the tight-buffered optical fiber are responsible for the transmission of optical signals of one unit cell.

[0012] The beneficial effects of the small-diameter precision short elemental spacing close-packed array provided by the present application are: the small-diameter precision short elemental spacing close-packed array of the present application has a small outer diameter and a small element spacing; specifically: the array outer diameter is φ27mm, the element spacing is 0.25m, the internal structural parts are closely packed, and the internal structure design is reasonably optimized and arranged; at the same time, a delay ring skeleton is specially designed, which can not only meet the requirements for placing the delay ring, but also play the role of placing optical devices, accommodating fusion points and redundant optical fibers, and finally forming a small-diameter precision short elemental spacing close-packed array. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0014] Figure 1 A schematic diagram of the layout structure of a small-diameter precision short-element-pitch close-packed array provided in an embodiment of the present application;

[0015] Figure 2 A schematic diagram of the optical signal transmission connection relationship of each two-color tight-buffered optical fiber responsible for one path of 32 primitives in a small-diameter precision short primitive spacing close-packed array provided in an embodiment of the present application;

[0016] Figure 3 A schematic diagram of the three-dimensional structure of a time-delay skeleton in a small-diameter precision short-element-pitch close-packed array provided in an embodiment of the present application;

[0017] Figure 4 A schematic diagram of the lower shell structure of the time-delay skeleton provided in an embodiment of the present application;

[0018] Figure 5 Schematic diagram of the upper shell structure of the delay skeleton provided in an embodiment of the present application.

[0019] Among them, the reference numerals in the figure are:

[0020] 1. PU tube; 2. Fiber collection skeleton assembly; 3. Plug core assembly; 4. Probe skeleton; 5. Delay skeleton; 51. Upper shell; 52. Lower shell; 53. Screws; 54. First cavity; 55. Second cavity; 6. Wavelength division multiplexer; 7. Fiber coupler; 8. Hydrophone probe; 9. Delay loop assembly; 10. Optical device; 11. Transmission cable. DETAILED DESCRIPTION

[0021] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0022] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0023] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0024] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0025] like Figure 1-Figure 5 As shown, a small-diameter precision short element spacing close-packed array provided in an embodiment of the present application is now described. The small-diameter precision short element spacing close-packed array comprises: a PU tube 1, a plugging core assembly 3, a fiber collection skeleton assembly 2, a probe skeleton 4 and a delay skeleton 5.

[0026] Among them, the plugging core assembly 3 is arranged at one end of the PU tube 1 for sealing the transmission cable 11 through the plugging core assembly 3 and passing it into the PU tube 1. The fiber collecting skeleton assembly 2 is between the plugging core assembly 3 and the first probe skeleton 4. The fiber collecting skeleton assembly 2 is provided with a wavelength division multiplexer 6 and an optical fiber coupler 7; Figure 2As shown, specifically, the transmission cable 11 is an eight-color tight-buffered optical fiber, and each two-color tight-buffered optical fiber is responsible for the optical signal transmission of one element, completing the optical signal transmission and the reasonable routing and storage of the optical fiber in a limited space, which greatly improves the internal space utilization of the array.

[0027] Among them, multiple probe skeletons 4 and time delay skeletons 5 are provided, and multiple are arranged in a staggered array in the PU tube 1. Among them, a hydrophone probe 8 is provided in the probe skeleton 4, and a delay ring assembly 9 and an optical device 10 are provided in the delay skeleton 5. The outer diameters of the probe skeleton 4 and the delay skeleton 5 are both 22.2 mm; the spacing between the probe skeleton 4 and the delay skeleton 5 is 45 mm, the length of the delay skeleton 5 is 100 mm, the length of the probe skeleton 4 is 60 mm, and the spacing between two adjacent hydrophone probes 8 is 250 mm, so that the unit spacing is 0.25 m.

[0028] In this embodiment, the probe frame 4 and the delay frame 5 are both made of high-strength materials and adopt a separate design, which can achieve high sensitivity and miniaturization functions; due to the size limitation of the hydrophone probe and the pressure resistance requirement, the outer diameter of the frame of this embodiment is 22.2 mm, which has basically reached the minimum size limit.

[0029] In this embodiment, the inner diameter of the PU tube 1 is 22mm, the wall thickness is 2.5mm, and the size can have a certain tolerance; this makes the outer diameter of the array 27mm, the element spacing is 0.25m, and the optical fiber hydrophone, optical device 10, probe skeleton 4, and delay skeleton 5 are placed in a small space; at the same time, the setting of the delay skeleton 5 can not only meet the requirements of placing the delay ring, but also play the role of storing the fusion point and redundant optical fiber. Through the above array internal structure design, a small diameter precision short element spacing dense array is formed. The specific parameters of the small diameter precision short element spacing dense array are: 1. Array outer diameter: 27mm±1mm; 2. Working frequency band: 20Hz~7.5kHz; 3. Array element sound pressure sensitivity ≥-145.0dB (0dB~1rad / μPa); 4. Element spacing: 0.25m±0.01m.

[0030] like Figure 3-Figure 5 As shown, in this embodiment, a first cavity 54 and a second cavity 55 are provided in the time-delay skeleton 5. The first cavity 54 is used to place the time-delay ring assembly 9, and the second cavity 55 is used to place the optical device 10, the fusion point and the redundant optical fiber storage. Specifically, the time-delay skeleton 5 includes an upper shell 51 and a lower shell 52, and the upper shell 51 and the lower shell 52 are fixed by a plurality of screws 53, so that it is convenient to operate the various components in the time-delay skeleton 5.

[0031] The small-diameter precision short element spacing close-packed array provided in this embodiment, the small-size precision element is used to improve the sensitivity and working frequency band of the optical fiber hydrophone, and the range can reach 20Hz-7.5KHz; the element spacing is close-packed to form a modular sub-array, and the array is formed by connecting n sub-arrays in series, and then m arrays are arranged on the left and right sides of the ship, thereby increasing the array space gain and improving the system dynamic range. As the scale of the optical fiber hydrophone array will become larger and larger, the detection capability of low-frequency weak underwater acoustic signals will become stronger and stronger.

[0032] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A small diameter precision short element spacing close-packed array, characterized in that: include: A PU tube (1), a probe skeleton (4) and a time-delay skeleton (5), wherein a plurality of the probe skeletons (4) and the time-delay skeleton (5) are arranged in an array in the PU tube (1), a hydrophone probe (8) is arranged in the probe skeleton (4), a delay ring assembly (9) and an optical device (10) are arranged in the time-delay skeleton (5), and the outer diameters of the probe skeleton (4) and the time-delay skeleton (5) are both 22.2 mm; the distance between the probe skeleton (4) and the time-delay skeleton (5) is 45 mm, the length of the time-delay skeleton (5) is 100 mm, the length of the probe skeleton (4) is 60 mm, and the distance between two adjacent hydrophone probes (8) is 250 mm.

2. The small diameter precision short element spacing close-packed array according to claim 1, characterized in that: The inner diameter of the PU tube (1) is 22 mm and the wall thickness is 2.5 mm.

3. The small diameter precision short element spacing close-packed array according to claim 1, characterized in that: A first cavity (54) and a second cavity (55) are provided in the time-delay skeleton (5); the time-delay ring assembly (9) is arranged in the first cavity (54); and the optical device (10) is arranged in the second cavity (55).

4. The small diameter precision short element spacing close-packed array according to claim 3, characterized in that: The time-delay frame (5) comprises an upper shell (51) and a lower shell (52), and the upper shell (51) and the lower shell (52) are butt-jointed and fixed by a plurality of screws (53).

5. The small diameter precision short element spacing close-packed array according to any one of claims 1 to 4, characterized in that: A plugging core assembly (3) is provided at one end of the PU tube (1), and a transmission cable (11) is sealed and penetrated into the PU tube (1) through the plugging core assembly (3). A fiber receiving frame assembly (2) is provided between the plugging core assembly (3) and the first probe frame (4), and a wavelength division multiplexer (6) and an optical fiber coupler (7) are provided in the fiber receiving frame assembly (2).

6. The small diameter precision short element spacing close-packed array according to claim 5, characterized in that: The transmission cable (11) is an eight-color tight-buffered optical fiber, and every two colors of the tight-buffered optical fiber are responsible for the transmission of optical signals of one unit cell.

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