Optical fiber temperature sensing system loaded with air cooling structure

Abstract

The invention belongs to the field of optical fiber temperature sensing, and relates to an optical fiber temperature sensing system loaded with an air cooling structure, which comprises a coated black body cavity, one end of an optical fiber is arranged in the coated black body cavity, the other end of the optical fiber is sequentially connected with an optical filter and a photoelectric detector, and the air cooling structure for heat dissipation is arranged on the optical fiber; the photoelectric detector is electrically connected with a signal processing module, and the signal processing module is connected with a display module. The optical fiber temperature sensing system combines the advantages of a high-emissivity material blackbody cavity and a high-efficiency air cooling structure, and has the comprehensive performance of high temperature resistance, strong anti-interference capability, high measurement precision, good stability and the like. Compared with a traditional temperature sensor, the system is more excellent in performance in a high-temperature and severe environment, and long-term stable temperature monitoring can be realized.

Description

Technical Field

[0001] This invention belongs to the field of fiber optic temperature sensing and relates to a fiber optic temperature sensing system with a loaded air-cooling structure. Background Technology

[0002] Temperature is one of the most important physical quantities for determining the state of matter. The fundamental laws studied in thermodynamics, fluid mechanics, heat transfer, physics, chemistry, metallurgy, and other disciplines are all closely related to temperature. Furthermore, its measurement and control play a vital role in national defense, military affairs, scientific experiments, and industrial and agricultural production. With the development of science and technology, the accuracy and real-time performance of temperature measurement are receiving increasing attention. In particular, the continuous development and demands of fields such as industry, agriculture, scientific research, and national defense have strongly promoted the research and development of temperature measurement.

[0003] In recent years, fiber optic temperature sensors based on blackbody radiation have made some progress, including contact-non-contact temperature measurement methods that combine high-temperature resistant blackbody cavities with fiber optic radiation temperature measurement technology based on Planck's law. This method involves placing a blackbody cavity sensor with a calibrated blackbody emissivity in contact with the object being measured. Once thermal equilibrium is reached, the fiber optic radiation temperature measurement system measures the radiation emitted by the blackbody cavity sensor to obtain the object's true temperature. However, some problems still need to be solved. First, how to improve the emissivity of the blackbody cavity material to enhance the sensor's sensitivity. Second, how to optimize the sensor structure at a lower cost to improve measurement accuracy and stability to promote its widespread application. Given the growing demand for high-temperature and high-precision temperature measurement in industry, developing higher-performance and more practical blackbody radiation fiber optic sensors has significant practical importance and broad application prospects, providing more reliable temperature measurement solutions for industrial production and scientific research experiments. Summary of the Invention

[0004] The purpose of this invention is to provide a fiber optic temperature sensing system with an air-cooled structure, which aims to solve the problems of low emissivity, poor structural stability and insufficient heat dissipation performance faced by existing fiber optic temperature sensing systems when measuring at high temperatures.

[0005] To achieve the above objectives, the present invention employs the following technical solution: This application discloses a fiber optic temperature sensing system with a novel air-cooling structure, comprising: a coated blackbody cavity formed by copper-iron spinel coating on a whole fiber using the sol-gel method, and an air-cooling structure for connecting a matching sensing probe after the coated blackbody cavity.

[0006] Preferably, the air-cooling structure includes an embedded fiber optic type air-cooling outer sleeve, an embedded fiber optic type air-cooling inner sleeve is provided inside the embedded fiber optic type air-cooling outer sleeve, the embedded fiber optic type air-cooling outer sleeve is directly sleeved on the optical fiber, and an air-cooling inlet and an air-cooling outlet are respectively opened on the embedded fiber optic type air-cooling outer sleeve.

[0007] Preferably, the air-cooling structure is an embedded fiber optic air-cooling structure with a maximum length of 400mm and a maximum radius of 19mm.

[0008] Preferably, both the embedded fiber-optic type air-cooled inner sleeve and the embedded fiber-optic type air-cooled outer sleeve are made of high-temperature resistant silicon carbide material.

[0009] Preferably, the air-cooled inlet, the embedded fiber-optic air-cooled inner sleeve, the embedded fiber-optic air-cooled outer sleeve, and the air-cooled outlet form a "Z-shaped" air-cooled cavity.

[0010] Preferably, a CuFe2O4 composite material with added carbon nanotubes is used in the coated blackbody cavity.

[0011] Preferably, a CNT+ CuFe2O4 film is prepared on an optical fiber using the sol-gel method to construct a high-temperature resistant coated blackbody cavity, specifically including the following steps: Dissolve appropriate amounts of Cu(NO3)2•3H2O and Fe(NO3)3•9H2O separately in deionized water and stir until completely dissolved to obtain Cu-containing... 2+ Solution and Fe 3+ Solution; containing Cu 2+ Solution and Fe 3+ Mix the solutions and stir until they are evenly distributed to obtain a mixed solution; In the preparation of Cu 2+ and Fe 3+ After mixing the solution thoroughly, add 0.5% of ultrasonically dispersed carbon nanotubes and continue stirring to ensure uniform distribution.

[0012] Add an appropriate amount of citric acid to the mixed solution and stir thoroughly to adjust the pH value to the neutral range. Then heat the solution and continue stirring until it transforms into a thick gel. The optical fiber is slowly immersed into the gel in a vertical direction, and then slowly pulled out of the gel at the same speed to achieve the coating of the optical fiber. The coated optical fiber is gelled at room temperature to form a gel film. After the gel film is dried, it is calcined to finally form the coated blackbody cavity of the optical fiber.

[0013] Compared with the prior art, the present invention has the following beneficial effects: 1) The fiber optic temperature sensing system of this invention combines the advantages of a high-emissivity blackbody cavity material and a high-efficiency air-cooling structure, exhibiting comprehensive performance characteristics such as high temperature resistance, strong anti-interference capability, high measurement accuracy, and good stability. Compared with traditional temperature sensors, this system performs better in high-temperature and harsh environments, enabling long-term stable temperature monitoring.

[0014] 2) The air-cooled structure effectively solves the heat dissipation problem of the system in high-temperature environments. During high-temperature measurements, the fiber-coated blackbody cavity absorbs a large amount of heat. If heat cannot be dissipated in time, the probe temperature will become too high, affecting its performance and lifespan, and even causing increased measurement errors or system failure. Both the inner and outer sleeves of the air-cooled system are made of silicon carbide, which maintains stable physical and chemical properties in high-temperature environments and has good thermal conductivity. Through reasonable size design, the inner sleeve can quickly transfer the heat generated by the fiber-coated blackbody cavity to the surface, preparing for heat dissipation; the outer sleeve can withstand the working pressure in high-temperature environments, ensuring the normal operation of the entire air-cooled structure and ensuring stable operation of the system in high-temperature environments. The "Z-shaped" cavity design of the air-cooled structure, combined with the spiral cooling air duct, allows the cold air to form efficient convection within the air duct, increasing the contact area between the cold air and the outer sleeve wall. This allows for more even distribution of the cold air in the area requiring heat dissipation, promptly removing the heat generated by the probe and keeping the probe temperature within a reasonable range. This avoids the impact of excessive temperature on system performance and lifespan, effectively reducing measurement errors and improving the stability and reliability of the system in high-temperature environments.

[0015] 3) The blackbody cavity formed by the CuFe2O4 coating with added carbon nanotubes exhibits high emissivity, enabling more effective absorption and emission of thermal radiation. According to the principle of blackbody radiation, higher emissivity results in a more sensitive sensor response to temperature changes and higher measurement accuracy. The introduction of carbon nanotubes increases the surface roughness of the coating, causing multiple scattering of thermal radiation on the coating surface, thereby enhancing the absorption and emission capabilities of thermal radiation. Furthermore, the high thermal conductivity of carbon nanotubes facilitates rapid heat transfer within the coating, allowing for more uniform energy radiation when heated, further improving emissivity. In high-temperature environments, this system can accurately measure temperature with errors controlled within a small range, meeting the demands for high-precision temperature measurement and making it suitable for industrial production processes and scientific research fields with stringent temperature accuracy requirements. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the air-cooling structure of the present invention; Figure 2 This is a schematic diagram of the system structure according to an embodiment of the present invention; Figure 3 This is a flowchart illustrating the preparation process of the coated blackbody cavity according to an embodiment of the present invention.

[0018] Wherein: 1-coated blackbody cavity; 2-air-cooled air inlet; 3-embedded fiber-optic type air-cooled inner sleeve; 4-chuck; 5-embedded fiber-optic type air-cooled outer sleeve; 6-air-cooled air outlet; 7-fixing device; 8-fiber optic cable. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0020] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0021] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0022] In the description of the embodiments of the present invention, it should be noted that if terms such as "upper," "lower," "horizontal," or "inner" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. Furthermore, terms such as "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0023] Furthermore, the use of the term "horizontal" does not imply that the component must be absolutely horizontal, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0024] In the description of the embodiments of the present invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the present invention according to the specific circumstances.

[0025] The present invention will now be described in further detail with reference to the accompanying drawings: See Figure 1 This application discloses a fiber optic temperature sensing system with a novel air-cooling structure, comprising: a coated blackbody cavity 1 formed by copper-iron spinel coating on a whole fiber using the sol-gel method, and an air-cooling structure for matching a sensing probe connected to the coated blackbody cavity 1, forming an integrated temperature sensing probe that combines sensing, light transmission, and encapsulation.

[0026] In some embodiments, the air-cooling structure includes an embedded fiber optic type air-cooling outer sleeve 5, an embedded fiber optic type air-cooling inner sleeve 3 is provided inside the embedded fiber optic type air-cooling outer sleeve 5, the embedded fiber optic type air-cooling outer sleeve 3 is directly sleeved on the optical fiber 8, and an air-cooling inlet 2 and an air-cooling outlet 6 are respectively opened on the embedded fiber optic type air-cooling outer sleeve 5.

[0027] In some embodiments, the air-cooling structure is an embedded fiber optic air-cooling structure with a maximum length of 400mm and a maximum radius of 19mm.

[0028] In some embodiments, both the embedded fiber-optic type air-cooled inner sleeve 3 and the embedded fiber-optic type air-cooled outer sleeve 5 are made of high-temperature resistant silicon carbide material.

[0029] In some embodiments, the air-cooled inlet 2, the embedded fiber-optic air-cooled inner sleeve 3, the embedded fiber-optic air-cooled outer sleeve 5, and the air-cooled outlet 6 constitute a “Z-shaped” air-cooled cavity.

[0030] In some embodiments, a CuFe2O4 composite material with added carbon nanotubes is applied to the coated blackbody cavity 1, utilizing the properties of CuFe2O4 to enhance the blackbody cavity's absorption and emission capabilities for thermal radiation. According to the principle of blackbody radiation, high emissivity enables the sensor to more sensitively detect temperature changes, thereby improving measurement accuracy. In high-temperature environments, this high-emissivity blackbody cavity can effectively convert thermal energy into radiative energy, providing a stable and accurate signal source for subsequent sensing measurements.

[0031] In some embodiments, the air-cooling structure includes an embedded fiber-optic type air-cooling outer sleeve 5, within which is an embedded fiber-optic type air-cooling inner sleeve 3, which is fitted onto the optical fiber 8. The embedded fiber-optic type air-cooling outer sleeve 5 has an air-cooling inlet 2 and an air-cooling outlet 6. The air-cooling inlet 2, the embedded fiber-optic type air-cooling inner sleeve 3, the embedded fiber-optic type air-cooling outer sleeve 5, and the air-cooling outlet 6 form a "Z-shaped" cavity. The air-cooling structure is an embedded fiber-optic type air-cooling structure with a maximum length of 400mm and a maximum radius of 19mm. This special "Z-shaped" structural design allows for efficient convection of cold air within the air duct, maximizing the contact area between the cold air and the outer sleeve wall, thereby improving heat dissipation efficiency and ensuring that the cold air is evenly distributed throughout the entire outer sleeve, carrying away heat.

[0032] More preferably, the air-cooled inner sleeve 3 is made of silicon carbide material with a thickness of 1mm-3mm and a radius of 8mm-12mm. This material can maintain stable physical and chemical properties under high-temperature environments, while also having good thermal conductivity, enabling it to quickly transfer the heat generated by the fiber-coated blackbody cavity to the surface of the inner sleeve, preparing for the subsequent heat dissipation process.

[0033] More preferably, the air-cooled outer sleeve 3 is made of silicon carbide, with a thickness of 2mm-4mm and a radius of 11mm-19mm. It has good thermal conductivity and mechanical strength, and can withstand the working pressure in high-temperature environments.

[0034] In some embodiments, a CNT+ CuFe2O4 film is prepared on an optical fiber using a sol-gel method to construct a high-temperature resistant optical fiber blackbody cavity. The specific steps include: Cu(NO3)2•3H2O and Fe(NO3)3•9H2O were dissolved separately in deionized water and stirred until completely dissolved to obtain Cu-containing... 2+ Solution and Fe 3+ Solution; containing Cu 2+ Solution and Fe 3+ Mix the solutions and stir until they are evenly distributed to obtain a mixed solution; In the preparation of Cu 2+ and Fe 3+ After mixing the solution thoroughly, add 0.5% of ultrasonically dispersed carbon nanotubes and continue stirring to ensure uniform distribution.

[0035] Add citric acid to the mixed solution and stir. Adjust the pH of the solution to 7, then heat and stir until a viscous gel is formed. The optical fiber is vertically and slowly immersed into the gel, and then pulled out of the gel at the same speed to obtain a coated optical fiber. The coated optical fiber is gelled at room temperature to form a gel film, and the gel film is dried and then calcined to obtain a coated blackbody cavity.

[0036] In some embodiments, the optical fiber is vertically and slowly immersed into the gel at a rate of 3-4 mm / s for 4-5 minutes.

[0037] In some embodiments, citric acid is added to the mixed solution and stirred, the molar ratio of citric acid to total metal cations is 1:1, and the pH of the solution is adjusted to 7 using ammonia.

[0038] In some embodiments, see Figure 3 The blackbody cavity formed by CuFe2O4 coating specifically includes the following steps: 1) Dissolving and stirring: Weigh the raw materials according to a specific molar ratio of 2:3. Dissolve the weighed Cu(NO3)2•3H2O and Fe(NO3)3•9H2O in 50ml of deionized water respectively. Stir thoroughly under magnetic stirring until the solids are completely dissolved to obtain a solution containing Cu. 2+ and Fe 3+ The two solutions were mixed and stirred at 60°C for 2 hours to allow Cu to form a solution. 2+ and Fe 3+ The ions are evenly distributed in the solution.

[0039] 2) Gel formation: A certain amount of citric acid was added to the mixed solution, while maintaining a molar ratio of citric acid to total metal cations (CA / MC) of 1:1. The mixture was stirred continuously at 60°C for 2 hours. The pH of the solution was adjusted to 7 with ammonia to promote the reaction. The solution was further heated to 90°C and stirred until a viscous gel formed. The reaction is as follows:

[0040] 3) Fiber Cleaning and Activation: The fiber optic cable is ultrasonically cleaned sequentially with ethanol and deionized water for 15 minutes to remove oil, dust, and other impurities from the fiber surface. Then, the fiber surface is dried with nitrogen gas to ensure it is clean and dry. To improve the adhesion of the gel to the fiber surface, the cleaned fiber is immersed in a solution of aminopropyltriethoxysilane for 1-2 hours. The fiber is then removed and rinsed thoroughly with ethanol.

[0041] 4) Fiber Coating: The pretreated optical fiber is vertically and slowly immersed into the formed gel at a speed controlled at 3-4 mm / s for 4-5 minutes. Then, the optical fiber is pulled out of the gel at the same slow speed, within the range of 5. During the pulling process, a uniform liquid film is formed on the surface of the optical fiber.

[0042] 5) Coagulation and Calcination: The coated optical fiber is placed at room temperature for a period of time to allow the gel to gel on the fiber surface, forming a gel film. At this stage, the film has a certain strength and stability. The gelled optical fiber is then dried in an oven at 160-200°C for 8-12 hours to form a fluffy dry gel. The dried sample is then calcined in a furnace at 750-850°C for 6-8 hours. The calcination process can improve the crystallinity of CuFe2O4, remove impurities, and affect its crystal structure and properties.

[0043] In some embodiments, this application discloses a fiber optic temperature sensing system with a loaded air-cooling structure, comprising: a coated blackbody cavity 1, one end of an optical fiber 8 disposed within the coated blackbody cavity 1, the other end of the optical fiber 8 being sequentially connected to a filter and a photodetector, and an air-cooling structure for heat dissipation disposed on the optical fiber; the photodetector being electrically connected to a signal processing module, and the signal processing module being connected to a display module; and this application uses a high emissivity material CuFe2O4 for blackbody cavity coating; and designs an air-cooling structure.

[0044] For the blackbody cavity fiber optic temperature sensor, the CuFe2O4 sol impregnation speed is 3 mm / s, the fiber is immersed in the CuFe2O4 sol for 4 minutes, and the CuFe2O4 sol lifting speed is 4 mm / s. The coated fiber is then calcined in a furnace at 750°C. The air-cooling structure is chucked and fixedly mounted on the fiber and the coated blackbody cavity. The air-cooling structure consists of an outer air-cooling sleeve, an inner air-cooling sleeve, an air-cooling inlet, and an air-cooling outlet. The air-cooling structure adopts a Z-shaped structure, with the outlet on the upper right and the inlet on the lower left. The Z-shaped structure uses a high-temperature resistant and thermally conductive ceramic material for the inner sleeve to contact the blackbody cavity, combined with an aluminum alloy outer sleeve. The inner air-cooling sleeve of the probe has a spiral cooling air channel inside.

[0045] See Figure 2 This invention discloses a fiber optic temperature sensing system with a loaded air-cooling structure, aiming to solve the problems of low emissivity, poor structural stability, and insufficient heat dissipation performance faced by existing fiber optic temperature sensing systems during high-temperature measurements, and to achieve high-precision and high-reliability temperature measurement. The system includes: The coated blackbody cavity 1 is a key component of the entire sensing system. Its purpose is to achieve high emissivity through a specific coating process. In this system, a CuFe2O4 chemical coating with added carbon nanotubes is used to enhance the blackbody cavity's absorption and emission of thermal radiation. According to the principle of blackbody radiation, high emissivity allows the sensor to more sensitively detect temperature changes, thereby improving measurement accuracy. In high-temperature environments, this high-emissivity blackbody cavity can effectively convert thermal energy into radiant energy, providing a stable and accurate signal source for subsequent sensing measurements.

[0046] Fiber 8: Fiber 8 works closely with the coated blackbody cavity 1 to transmit the optical signals radiated by the coated blackbody cavity 1 to subsequent components. It not only serves as a transmission channel for optical signals, but also modulates and transmits temperature information through its interaction with the coated blackbody cavity 1, ensuring that temperature changes are accurately converted into changes in optical signals and effectively transmitted to subsequent components such as photodetectors for processing.

[0047] Air-cooling system: The entire air-cooling structure adopts a Z-shaped design. The embedded fiber-optic type air-cooled outer sleeve 5 is made of aluminum alloy, which has good thermal conductivity and mechanical strength, and can withstand the working pressure in high-temperature environments. The interior of the embedded fiber-optic type air-cooled outer sleeve 5 and the embedded fiber-optic type air-cooled inner sleeve 3 form a spiral cooling air channel. This special structural design allows the cold air to form efficient convection within the air channel, maximizing the contact area between the cold air and the outer sleeve wall, thereby improving heat dissipation efficiency and ensuring that the cold air can be evenly distributed throughout the entire outer sleeve to remove heat. The embedded fiber-optic type air-cooled inner sleeve 3 is made of a high-temperature resistant and thermally conductive ceramic material. This material can maintain stable physical and chemical properties in high-temperature environments, and also has good thermal conductivity, which can quickly transfer the heat generated by the blackbody cavity 1 on the fiber optic 8 to the surface of the embedded fiber-optic type air-cooled inner sleeve 3, preparing for the subsequent heat dissipation process.

[0048] Optical filters: Colorimetric thermometry measures the temperature of an object by comparing the ratio of radiance at different wavelengths, thus achieving high accuracy. An optical filter is an optical element that selectively transmits or blocks light of specific wavelengths. It is used to precisely filter optical signals according to system requirements.

[0049] Photodetectors: A photodetector is a device that converts light signals into electrical signals. When light shines on the photosensitive surface of a photodetector, photons interact with electrons in the photosensitive material, giving the electrons energy and generating a current or voltage signal. In this system, the first and second photodetectors utilize this principle to convert the light signal, after transmission through optical fibers and filtering by filters, into an electrical signal for subsequent signal processing and analysis. The performance of the photodetectors is crucial to the accuracy and stability of the entire system. They need to possess characteristics such as high sensitivity, low noise, and fast response to ensure accurate conversion of weak light signals into electrical signals and minimize errors and distortions during the signal conversion process.

[0050] Signal Processing Module: The signal processing module includes a signal amplification unit and a signal acquisition and processing unit. The signal amplification unit amplifies the received electrical signal and transmits it to the signal acquisition and processing unit. The signal acquisition and processing unit converts the electrical signal into a digital signal and analyzes it to obtain the temperature measurement result. The main function of the signal amplification module is to amplify the weak electrical signal output by the photodetector to enhance the signal strength, facilitating subsequent signal processing and analysis. It is typically implemented using an amplifier circuit, which can select appropriate amplification factor and bandwidth parameters according to different needs. During the amplification process, the signal-to-noise ratio needs to be considered to minimize noise amplification while maintaining signal linearity and stability. Through a carefully designed amplification circuit, the weak current signal or voltage signal at the nanoampere or microampere level output by the photodetector can be amplified to a suitable amplitude, providing a sufficiently strong signal source for subsequent signal acquisition and processing. The signal acquisition and processing section is responsible for acquiring the amplified electrical signal and converting it into a digital signal for further analysis and processing by a computer or other digital processing equipment. An ADC (Analog-to-Digital Converter) converts continuously changing analog electrical signals into discrete digital signals at a specific sampling frequency. The selection of the sampling frequency needs to be determined based on the signal's frequency characteristics and measurement requirements to ensure accurate capture of signal information while avoiding aliasing during sampling. After acquiring the digital signal, this module uses a series of algorithms to process and analyze the data. Through filtering, denoising, and feature extraction, interference components are removed from the signal, and temperature-related features are extracted. Then, based on a pre-set calibration curve or mathematical model, the processed signal is converted into a temperature value, and temperature compensation and error correction are performed to improve the accuracy and reliability of the measurement. The design of these algorithms and processing procedures must fully consider the system's measurement principles, sensor characteristics, and various factors in practical applications to ensure that the final temperature measurement results are accurate and reliable.

[0051] Display module: The display module presents the temperature information obtained after signal acquisition and processing to the user in an intuitive way.

[0052] In some embodiments, a fiber optic temperature sensing system with a loaded air-cooled structure is provided. The entire air-cooled structure is mounted on the optical fiber and the coated blackbody cavity 1 via a chuck 4 and a fixing device 7. The air-cooled structure mainly consists of an embedded fiber-optic type air-cooled outer sleeve 5, an embedded fiber-optic type air-cooled inner sleeve 3, an air-cooled inlet 2, and an air-cooled outlet 6. The entire air-cooled structure adopts a Z-shaped structure, which allows the cooling air to be distributed more evenly in the area requiring heat dissipation. Compared with traditional air-cooled structures, it can better ensure the temperature uniformity of each part, avoid excessive temperature differences, and thus improve the overall cooling effect. The air-cooled outer sleeve is made of silicon carbide and has a spiral cooling air channel inside to guide the airflow. The air-cooled inner sleeve is located inside the outer sleeve and is coaxially mounted with the outer sleeve. Its material is high-temperature resistant and has good thermal conductivity silicon carbide. The inner wall of the inner sleeve is tightly fitted to the optical fiber coated blackbody cavity, ensuring that heat can be effectively transferred from the probe to the surface of the inner sleeve. When the system is working, cold air enters the cooling duct of the air-cooled outer sleeve from the air-cooled air inlet, flows along the duct and exchanges heat with the surface of the air-cooled inner sleeve, carrying away the heat absorbed by the fiber-coated blackbody cavity, thereby maintaining the probe temperature within a relatively low and stable range, ensuring the normal operation of the system in high-temperature environments, and improving the stability and repeatability of measurements.

[0053] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A fiber optic temperature sensing system with a novel air-cooling structure, characterized in that, include: A coated blackbody cavity (1) is formed by copper-iron spinel coating on the entire optical fiber using the sol-gel method, and the coated blackbody cavity (1) is connected to a matching sensing probe by an air-cooled structure.

2. The fiber optic temperature sensing system with a loaded air-cooled structure according to claim 1, characterized in that, The air-cooling structure includes an embedded fiber optic type air-cooling outer sleeve (5), an embedded fiber optic type air-cooling inner sleeve (3) is provided inside the embedded fiber optic type air-cooling outer sleeve (5), the embedded fiber optic type air-cooling outer sleeve (3) is directly sleeved on the optical fiber (8), and an air-cooling inlet (2) and an air-cooling outlet (6) are respectively opened on the embedded fiber optic type air-cooling outer sleeve (5).

3. The fiber optic temperature sensing system with a loaded air-cooled structure according to claim 2, characterized in that, The air-cooling structure is an embedded fiber optic type air-cooling structure with a maximum length of 400mm and a maximum radius of 19mm.

4. The fiber optic temperature sensing system with a loaded air-cooled structure according to claim 2, characterized in that, Both the embedded fiber-optic type air-cooled inner sleeve (3) and the embedded fiber-optic type air-cooled outer sleeve (5) are made of high-temperature resistant silicon carbide material.

5. The fiber optic temperature sensing system with a loaded air-cooled structure according to claim 2, characterized in that, The air-cooled inlet (2), the embedded fiber-optic air-cooled inner sleeve (3), the embedded fiber-optic air-cooled outer sleeve (5), and the air-cooled outlet (6) form a "Z-shaped" air-cooled cavity.

6. The fiber optic temperature sensing system with a loaded air-cooled structure according to claim 1, characterized in that, CuFe2O4 composite material with added carbon nanotubes was used in the coating blackbody cavity (1).

7. A fiber optic temperature sensing system with a loaded air-cooled structure according to claim 6, characterized in that, A CNT+ CuFe2O4 film was prepared on an optical fiber using the sol-gel method to construct a high-temperature resistant coated blackbody cavity (1). The specific steps included: Dissolve appropriate amounts of Cu(NO3)2•3H2O and Fe(NO3)3•9H2O separately in deionized water and stir until completely dissolved to obtain Cu-containing... 2+ Solution and Fe 3+ Solution; containing Cu 2+ Solution and Fe 3+ Mix the solutions and stir until they are evenly distributed to obtain a mixed solution; In the preparation of Cu 2+ and Fe 3+ After mixing the solution thoroughly, add 0.5% of ultrasonically dispersed carbon nanotubes and continue stirring to ensure uniform distribution. Add an appropriate amount of citric acid to the mixed solution and stir thoroughly to adjust the pH value to the neutral range. Then heat the solution and continue stirring until it transforms into a thick gel. The optical fiber is slowly immersed into the gel in a vertical direction, and then slowly pulled out of the gel at the same speed to achieve the coating of the optical fiber. The coated optical fiber is gelled at room temperature to form a gel film. After the gel film is dried, it is calcined to finally form the coated blackbody cavity of the optical fiber (1).

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