Hollowed-out net-shaped sensing optical fiber sensitization structure and manufacturing method

Abstract

The invention discloses a hollow netted sensing optical fiber sensitization structure and a manufacturing method, and relates to the technical field of optical fiber sensing, and the hollow netted sensing optical fiber sensitization structure is characterized in that an elastic sensitization layer is arranged on the outer side of an inner support skeleton; the sensing optical fiber layer is wound on the elastic sensitization layer; the inner supporting framework is arranged in the outer supporting framework; the two ends of the inner supporting framework and the outer supporting framework are seamlessly connected with the upper end face and the lower end face respectively. The optical fiber sensor is simpler than an interference type optical fiber sensor, higher in sensitivity than a grating type optical fiber sensor, and higher in multiplexing capability than a distributed optical fiber sensor. Meanwhile, the sensing optical fiber sensitization structure also has the advantages of small size, light weight and the like. The device is simple in structure and easy to assemble, adopts a high-temperature-resistant, high-pressure-resistant and corrosion-resistant material, has both strength and elasticity, and can be used for exploration and real-time monitoring of underground oil and gas resources.

Description

Technical Field

[0001] The present invention belongs to the technical field of optical fiber sensing, and relates to a hollow mesh-shaped optical fiber sensing fiber sensitization structure and a manufacturing method thereof. Background Technique

[0002] An optical fiber sensor is an instrument that is sensitive to changes in the surrounding environment such as temperature, pressure, vibration, flow rate, noise, etc. based on the optical fiber itself, and converts the signal to be measured into an optical signal for detection. Compared with traditional piezoelectric sensors, optical fibers have the advantages of being integrated with sensing, intrinsically passive, high sensitivity, stable performance, long-distance wide-band high-speed transmission, etc., which promote the development of optical fiber sensors towards miniaturization, anti-electromagnetic interference, wide dynamic response, and long-term continuous monitoring, solving the problems of traditional piezoelectric sensors such as complex structure, low sensitivity, poor stability, and low transmission rate, and having important application value in the field of underground oil and gas resource exploration.

[0003] Optical fiber logging is a new technology developed based on optical fiber sensing technology, and its core is an optical fiber sensor. However, with the continuous deepening of the development of deep oil and gas resources, the exploration environment has become increasingly complex, and the actual situation has put forward higher requirements for the performance parameters of optical fiber sensors, especially in terms of sensitivity, resolution, high temperature and high pressure resistance, etc. In terms of production logging, the target layer for oil and gas exploration has extended from the middle layer to the deep layer, and even the ultra-deep layer. The existing optical fiber sensors are not convenient to work stably for a long time in the deep high-temperature and high-pressure environment. These factors have greatly restricted the development and popularization application of optical fiber sensors. Therefore, it is particularly important to improve the high temperature and high pressure resistance performance, sensitivity and longitudinal resolution of optical fiber detection instruments to accurately identify reservoirs.

[0004] Currently, the three most widely used optical fiber sensors in the industry are: distributed optical fiber sensors, grating-type optical fiber sensors, and interferometric optical fiber sensors. When light waves propagate in an optical fiber, backward scattered light will be generated. Using the optical fiber as a sensitive structure or component, the backward scattering generated at each point along the optical fiber is detected. Through the relationship between these backward scattered lights and the measured quantities (such as temperature, stress, vibration, etc.), changes occurring at any point in space can be detected, thereby realizing distributed optical fiber sensing. Currently, the most important indicators of distributed optical fiber are the detection distance and spatial resolution. The detection distance represents the size of the detection range of the distributed optical fiber sensor, and the spatial resolution represents the positioning accuracy of the sound source. The distributed optical fiber sensing system based on an optical time domain reflectometer has a large detection distance, but a low spatial resolution, and it is necessary to balance the relationship between the two in practical applications.

[0005] Grating-based fiber optic sensing involves writing gratings on the fiber core, causing the axial refractive index of the core to form a periodic distribution, which acts as a mirror at the grating position, thereby reflecting the matching frequency (wavelength) in the incident light. This specific wavelength is called the central wavelength of the grating. Utilizing the reflection characteristics and wavelength selectivity of the grating, when the grating is subjected to external temperature, stress, etc., its effective refractive index and grating pitch will change, thereby causing a shift in the central wavelength of the reflection spectrum. The amount of shift in the central wavelength is linearly related to the change in the parameter to be measured. By receiving and demodulating the amount of wavelength shift at the receiving end, the magnitudes of parameters such as temperature and stress around the grating point to be measured can be determined. Grating-based fiber optic sensors have many advantages such as long transmission distance and the ability to form distributed networks. However, currently, the sensitivity of grating-based fiber optic sensors is generally low, and the measurement errors brought by various sensitization structures are relatively large.

[0006] Interferometric fiber optic sensing is based on the principle of fiber optic interferometers. Usually, an elastomer is used as the conversion medium to apply the strain caused by vibration acceleration to the sensing fiber, causing a phase change in the light wave in the sensing fiber. This phase change represents the measured acceleration value. By receiving and demodulating the phase information in real time, the vibration acoustic wave waveform can be obtained. Commonly used fiber optic interferometers include Michelson interferometers and Mach-Zehnder interferometers. Interferometric fiber optic sensors have advantages such as high sensitivity, low noise, and large dynamic range, but they also have problems such as relatively large sensor volume, complex structure, and manufacturing process. Summary of the Invention

[0007] The purpose of the present invention is to solve the problems in the prior art that distributed fiber optic sensors have a large detection distance but relatively low spatial resolution; grating-based fiber optic sensors have relatively low sensitivity and large measurement errors brought by various sensitization structures; and interferometric fiber optic sensors have relatively large volume, complex structure, and manufacturing process. A hollow mesh-shaped sensitization structure for sensing fiber and its manufacturing method are provided.

[0008] To achieve the above object, the present invention adopts the following technical solutions:

[0009] A hollow mesh-shaped sensitization structure for sensing fiber, comprising: an integrated fiber optic sensing element and an outer support skeleton; the integrated fiber optic sensing element includes an inner support skeleton, an elastic sensitization layer, a sensing fiber layer, an upper end face, and a lower end face;

[0010] The elastic sensitization layer is arranged outside the inner support skeleton; the sensing fiber layer is wound around the elastic sensitization layer; the inner support skeleton is arranged inside the outer support skeleton; and both ends of the inner support skeleton and the outer support skeleton are seamlessly connected to the upper end face and the lower end face respectively.

[0011] A further improvement of the present invention lies in:

[0012] Further, the inner support skeleton is a hollow cylindrical structure with an axial through hole in the center.

[0013] Furthermore, the outer support skeleton adopts a hollow mesh structure with evenly distributed mesh holes. Sound transmission holes are left on the outer wall of the outer support skeleton for applying acoustic wave signals to the elastic sensitization layer, causing the elastic sensitization layer to produce compressive and tensile deformations.

[0014] Furthermore, the elastic sensitization layer is a thin-walled cylindrical structure. The elastic sensitization layer and the inner support skeleton share the same axis. The cylinder wall of the elastic sensitization layer is a hollow mesh structure, and there is a certain arc at the edge of each mesh hole of the elastic sensitization layer to avoid bending of the sensing optical fiber during the winding process.

[0015] Furthermore, the sensing optical fiber layer is helically wound around the outer surface of the elastic sensitization layer and then fixed by a high-temperature resistant adhesive. The sensing optical fiber layer is a single-mode optical fiber.

[0016] Furthermore, both the upper end face and the lower end face adopt a hollow hole structure. The radii of the upper end face and the lower end face are greater than the radius of the elastic sensitization layer. The upper end face and the lower end face form a baffle structure at both ends of the elastic sensitization layer to protect the sensing optical fiber layer wound on the outer surface of the elastic sensitization layer.

[0017] Furthermore, the edges of the hollow holes on the upper end face and the lower end face adopt a smooth chamfer structure, enabling the head and tail ends of the sensing optical fiber to smoothly transition from the upper end face or the lower end face to the elastic sensitization layer, avoiding bending of the sensing optical fiber at the inflection points of the upper end face or the lower end face, which may cause optical transmission loss.

[0018] Furthermore, the outer support skeleton is adhesively fixed to the upper end face and the lower end face respectively by a high-temperature resistant adhesive.

[0019] A manufacturing method of a hollow mesh sensing optical fiber sensitization structure includes:

[0020] S1: Tighten and compress both ends of the elastic sensitization layer with elastic straps, and adjust the tightness of the elastic straps so that the compression amounts at both ends are equal and the forces are the same;

[0021] S2: Horizontally clamp and fix the integrated optical fiber sensing element on the optical fiber winding machine, and move the starting point of winding to the middle position of the integrated optical fiber sensing element;

[0022] S3: Set relevant parameters such as rotation speed, moving step size, and number of winding turns, and fix the head end of the sensing optical fiber to the outer surface of the elastic sensitization layer with a high-temperature resistant adhesive;

[0023] S4: Start the manufacturing operation of winding the sensing optical fiber. During the winding process, observe whether the arrangement of the sensing optical fiber is uniform and whether there is any wire pressing, and keep the surface tension of the sensing optical fiber constant;

[0024] S5: After the winding is completed, fix the tail end of the sensing optical fiber to the outer surface of the elastic sensitization layer with a high-temperature resistant adhesive;

[0025] S6: Remove the completed integrated optical fiber sensing element and release the elastic tie.

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

[0027] In the present invention, an elastic sensitization layer is provided on the outer side of the inner support skeleton; the sensing optical fiber layer is wound around the elastic sensitization layer; the inner support skeleton is arranged inside the outer support skeleton; and both ends of the inner support skeleton and the outer support skeleton are seamlessly connected to the upper end face and the lower end face respectively. The present invention is simpler than the interferometric optical fiber sensor, has higher sensitivity than the fiber grating sensor, and has stronger multiplexing ability than the distributed optical fiber sensor. At the same time, the sensing optical fiber sensitization structure also has the advantages of small volume and light weight. The structure of the present invention is simple, easy to assemble, and uses high-temperature and high-pressure resistant and corrosion-resistant materials, with both strength and elasticity, and can be used for downhole oil and gas resource exploration and real-time monitoring. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for use in the embodiments. It should be understood that the following drawings only show some embodiments of the present invention, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0029] Figure 1 It is a three-dimensional schematic diagram of a hollow reticulated sensing optical fiber sensitization structure of the present invention;

[0030] Figure 2 It is a front view of a hollow reticulated sensing optical fiber sensitization structure of the present invention;

[0031] Figure 3 It is a flowchart of winding a hollow reticulated sensing optical fiber of the present invention;

[0032] Figure 4 (a) is an experimental schematic diagram of an optical fiber sensor with a hollow reticulated sensing optical fiber sensitization structure;

[0033] Figure 4 (b) is an experimental schematic diagram of an optical fiber sensor with a common structure.

[0034] Among them, 1 - integrated optical fiber sensing element; 2 - outer support skeleton; 101 - inner support skeleton; 102 - elastic sensitization layer; 103 - sensing optical fiber layer; 104 - upper end face; 105 - lower end face. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0035] To make the objectives, 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 accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. The components of the embodiments of the present invention usually described and illustrated in the accompanying drawings here can be arranged and designed in various different configurations.

[0036] Therefore, the detailed description of the embodiments of the present invention provided in the accompanying drawings below is not intended to limit the scope of the claimed present invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0037] It should be noted that like reference numerals and letters denote like items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0038] In the description of the embodiments of the present invention, it should be noted that if terms such as "upper", "lower", "horizontal", "inner", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the inventive product is usually placed during use, it is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying 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 construed as a limitation of the present invention. In addition, terms such as "first", "second", etc. are only used for descriptive distinction and cannot be construed as indicating or implying relative importance.

[0039] In addition, if the term "horizontal" appears, it does not mean that the component is required to be absolutely horizontal, but it can be slightly inclined. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but it can be slightly inclined.

[0040] In the description of the embodiments of the present invention, it should also be noted that unless otherwise clearly specified and limited, if terms such as "set", "installed", "connected", "connected" are understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0041] The present invention will be further described in detail below with reference to the accompanying drawings:

[0042] SeeFigure 1 and Figure 2 , the present invention discloses a hollow mesh - type fiber optic sensor sensitization structure, comprising: an integrated fiber optic sensing element 1 and an outer support framework 2; the integrated fiber optic sensing element 1 includes an inner support framework 101, an elastic sensitization layer 102, a sensing fiber layer 103, an upper end face 104, a lower end face 105 and a high - temperature resistant epoxy resin adhesive;

[0043] The elastic sensitization layer 102 is arranged outside the inner support framework 101; the sensing fiber layer 103 is wound around the elastic sensitization layer 102; the inner support framework 101 is arranged inside the outer support framework 2; both ends of the inner support framework 101 and the outer support framework 2 are seamlessly connected to the upper end face 104 and the lower end face 105 respectively.

[0044] The inner support framework 101 is a hollow cylindrical structure with an axial through - hole left in the center. The outer support framework 2 adopts a hollow mesh structure with evenly distributed mesh holes. Sound - transmitting holes are left on the outer wall of the outer support framework 2 for applying acoustic wave signals to the elastic sensitization layer 102, so that the elastic sensitization layer 102 generates compressive and tensile deformations. The elastic sensitization layer 102 is a thin - walled cylindrical structure. The elastic sensitization layer 102 is co - axial with the inner support framework 101. The cylindrical wall of the elastic sensitization layer 102 is a hollow mesh structure. There is a certain arc at the edge of each mesh hole of the elastic sensitization layer 102 to avoid bending of the sensing fiber during the winding process.

[0045] The sensing fiber layer 103 is helically wound around the outer surface of the elastic sensitization layer 102 and then fixed by a high - temperature resistant adhesive. The sensing fiber layer 103 is a single - mode weak grating fiber. Both the upper end face 104 and the lower end face 105 adopt a hollow hole - like structure. The radii of the upper end face 104 and the lower end face 105 are larger than the radius of the elastic sensitization layer 102. The upper end face 104 and the lower end face 105 form a baffle structure at both ends of the elastic sensitization layer 102 to protect the sensing fiber layer 103 wound on the outer surface of the elastic sensitization layer 102. The hollow hole - like edges of the upper end face 104 and the lower end face 105 adopt a smooth chamfer structure, so that the head and tail ends of the sensing fiber are smoothly transitioned from the upper end face 104 or the lower end face 105 to the elastic sensitization layer 102, avoiding bending of the sensing fiber at the inflection points of the upper end face 104 or the lower end face 105, which may cause optical transmission loss. The outer support framework 2 is bonded and fixed to the upper end face 104 and the lower end face 105 respectively through a high - temperature resistant epoxy resin adhesive.

[0046] Both the integrated fiber optic sensing element 1 and the outer support framework 2 are made of materials such as polyether ether ketone that are resistant to high temperature and high pressure, and are integrally formed by 3D printing technology, having both strength and elasticity.

[0047] The integrated optical fiber sensing element 1 is used to enhance the vibration sensitivity of the sensing optical fiber. A plurality of optical fiber sensing elements can be connected in series to form an optical fiber sensor array structure, thereby improving the longitudinal resolution of the detection instrument. At the same time, the distance between adjacent optical fiber sensing elements should be less than the longitudinal resolution of the sensing element itself.

[0048] The sensing optical fiber layer 103 is helically and tightly wound around the outer surface of the elastic sensitivity enhancement layer 102. During the winding process, the tension is constant, and the magnitude of the tension is in the range of 0.1 - 0.5 N. After winding, it is fixed by a high-temperature resistant epoxy resin adhesive. The length of the sensing optical fiber wound on the elastic sensitivity enhancement layer 102 is greater than 5 meters to ensure that two fiber Bragg gratings are located on one optical fiber sensing element. The outer surface of the sensing optical fiber is coated with a high-temperature resistant coating.

[0049] Embodiment:

[0050] See Figure 3 , Figure 3 which discloses a manufacturing method of a hollow mesh structure for enhancing the sensitivity of a sensing optical fiber. When vibration sound waves act on the elastic sensitivity enhancement layer 102 through the outer support framework 2, the elastic sensitivity enhancement layer 102 utilizes its own structural elasticity to convert the minute deformation generated during vibration compression and expansion into the change amount per unit length of the sensing optical fiber, thereby effectively improving the sensitivity of the optical fiber sensing element.

[0051] Use elastic straps to tightly tie and compress both ends of the elastic sensitivity enhancement layer 102, and make the forces on both ends of the elastic sensitivity enhancement layer 102 the same. Horizontally clamp and fix the integrated optical fiber sensing element 1 on the optical fiber winding machine, and by adjusting the starting position parameters, move the starting winding point to the middle position of the integrated optical fiber sensing element 1. Use the optical fiber winding machine to helically and tightly wind the sensing optical fiber around the outer surface of the elastic sensitivity enhancement layer 102. During the winding process, always keep the tension constant, and the magnitude of the tension is in the range of 0.1 - 0.5 N. Fix the wound sensing optical fiber with a high-temperature resistant epoxy resin adhesive, and remove the elastic straps.

[0052] Use a signal generator to output a pulse signal with a period of 500 ms and an amplitude of 300 mV. After being amplified by a power amplifier, a stable pulse sound wave signal is generated in water by an acoustic transducer. Place the sensing optical fiber sensitivity enhancement element and an optical fiber sensor with a common structure in series in the same water tank, ensure that the source distances of both are equal, and respectively receive the acoustic vibration signals propagated to the optical fiber sensor. Combining with the same demodulation device, the comparison results of the pulse sound wave signals received by the two optical fiber sensors are as shown in Figure 4 (a) and Figure 4 (b), and it can be found that the sensing optical fiber sensitivity enhancement element has higher sensitivity.

[0053] When the pulsed acoustic wave signal passes through the sound-transmitting holes of the outer support framework 2 and acts on the elastic sensitizing layer 102, the elastic sensitizing layer 102 utilizes its own structural elasticity to generate compressive and tensile deformations under the influence of the external sound pressure. Since the sensing optical fiber layer 103 is closely wound around the outer surface of the elastic sensitizing layer 102, the sensing optical fiber is in a stretched state and has a certain tension. When the elastic sensitizing layer 102 undergoes a small deformation, the sensing optical fiber layer 103 is squeezed by the elastic sensitizing layer 102, and the sensing optical fiber is stretched, that is, the change amount of the optical fiber per unit length increases. In addition to the influence of the small deformation generated by the elastic sensitizing layer 102, the pulsed acoustic wave signal also directly acts on the sensing optical fiber layer 103, further increasing the change amount of the optical fiber per unit length. Compared with the optical fiber sensor with a common structure that is only affected by the acoustic wave vibration factor, the sensing optical fiber sensitizing element further improves the sensitivity of the sensing optical fiber element under the combined action of the elastic sensitizing layer 102 and the pulsed acoustic wave vibration.

[0054] Meanwhile, when a weak noise signal acts on the sensing optical fiber layer 103, the sensing optical fiber in the stretched state has a certain tension, which causes it to generate a hindering effect on the micro-vibration, reducing the influence of the background noise on the sensing optical fiber. For the target acoustic wave signal, its sound pressure intensity exceeds the surface tension of the sensing optical fiber, causing the sensing optical fiber to vibrate so that it can receive the acoustic wave signal. The winding process of the sensing optical fiber layer 103 determines the magnitude of the surface tension of the sensing optical fiber, further affecting its cut-off threshold for the weak noise signal, realizing the filtering process of the received vibration signal, and thus effectively identifying the target acoustic wave signal. The sensing optical fiber sensitizing element is made of polyether ether ketone material, which can withstand extreme environments such as high temperature, high pressure, and corrosion, realizing the application of this sensing optical fiber sensitizing structure in oil and gas wells for measuring downhole acoustic wave vibration signals.

[0055] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A hollow mesh-shaped sensitizing structure for a sensing optical fiber, characterized in that, Comprising: An integrated optical fiber sensing element (1) and an outer support skeleton (2); the integrated optical fiber sensing element (1) includes an inner support skeleton (101), an elastic sensitizing layer (102), a sensing optical fiber layer (103), an upper end face (104), and a lower end face (105); The elastic sensitizing layer (102) is arranged outside the inner support skeleton (101); the sensing optical fiber layer (103) is wound around the elastic sensitizing layer (102); the inner support skeleton (101) is arranged inside the outer support skeleton (2); both ends of the inner support skeleton (101) and the outer support skeleton (2) are seamlessly connected to the upper end face (104) and the lower end face (105) respectively.

2. The hollow mesh-shaped sensitizing structure for a sensing optical fiber according to claim 1, characterized in that, The inner support skeleton (101) is a hollow cylindrical structure with an axial through-hole left in the center.

3. The hollow mesh-shaped sensitizing structure for a sensing optical fiber according to claim 2, characterized in that, The outer support skeleton (2) adopts a hollowed-out mesh structure with evenly distributed mesh holes, and sound transmission holes are left on the outer wall of the outer support skeleton (2) for applying acoustic wave signals to the elastic sensitizing layer (102) to cause compressive and tensile deformation of the elastic sensitizing layer (102).

4. The hollow mesh-shaped sensitizing structure for a sensing optical fiber according to claim 3, characterized in that, The elastic sensitizing layer (102) is a thin-walled cylindrical structure, the elastic sensitizing layer (102) is coaxial with the inner support skeleton (101), the cylindrical wall of the elastic sensitizing layer (102) is a hollowed-out mesh structure, and there is a certain arc at the edge of each mesh hole of the elastic sensitizing layer (102) to avoid bending of the sensing optical fiber during the winding process.

5. The hollow mesh-shaped sensitizing structure for a sensing optical fiber according to claim 4, characterized in that, The sensing optical fiber layer (103) is helically wound around the outer surface of the elastic sensitizing layer (102) and then fixed by a high-temperature resistant adhesive, and the sensing optical fiber layer (103) is a single-mode optical fiber.

6. The hollow mesh-shaped sensitizing structure for a sensing optical fiber according to claim 5, characterized in that, Both the upper end face (104) and the lower end face (105) adopt a hollowed-out hole-like structure, the radii of the upper end face (104) and the lower end face (105) are greater than the radius of the elastic sensitizing layer (102), and the upper end face (104) and the lower end face (105) form a baffle structure at both ends of the elastic sensitizing layer (102) to protect the sensing optical fiber layer (103) wound on the outer surface of the elastic sensitizing layer (102).

7. The hollow mesh-shaped sensitizing structure for a sensing optical fiber according to claim 6, characterized in that, The hollowed-out hole-like edges of the upper end face (104) and the lower end face (105) adopt a smooth chamfer structure, so that the head and tail ends of the sensing optical fiber are smoothly transitioned from the upper end face (104) or the lower end face (105) to the elastic sensitizing layer (102), avoiding bending of the sensing optical fiber at the inflection points of the upper end face (104) or the lower end face (105) and resulting in optical transmission loss.

8. The hollow mesh-shaped sensitizing structure for a sensing optical fiber according to claim 7, characterized in that, The outer support skeleton (2) is adhesively fixed to the upper end face (104) and the lower end face (105) respectively by a high-temperature resistant adhesive.

9. A manufacturing method for the hollow mesh-shaped sensitizing structure for a sensing optical fiber according to claim 8, characterized in that, Comprising: S1: Tighten and compress both ends of the elastic sensitizing layer (102) with an elastic tie, and adjust the tightness of the elastic tie so that the compression amounts at both ends are equal and the forces are the same; S2: Horizontally clamp and fix the integrated optical fiber sensing element (1) on an optical fiber winding machine, and move the starting point of winding to the middle position of the integrated optical fiber sensing element (1); S3: Set relevant parameters such as rotational speed, moving step, and number of winding turns, and fix the head end of the sensing optical fiber on the outer surface of the elastic sensitizing layer (102) with a high-temperature resistant adhesive; S4: Start the operation of winding the sensing optical fiber. During the winding process, observe whether the arrangement of the sensing optical fiber is uniform and whether there is any pressure on the wire. Keep the surface tension of the sensing optical fiber constant; S5: After the winding is completed, use high-temperature resistant glue to fix the end of the sensing optical fiber on the outer surface of the elastic sensitization layer (102); S6: Remove the completed integrated optical fiber sensing element (1) and release the elastic tie.

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