Calibration device and method for micro wind speed sensor

Abstract

The invention provides a micro wind speed sensor calibration device and method, and relates to the technical field of wind speed measurement. The device comprises a power section, a rectification section, a test section, a protection section and a micro wind speed detection system which are arranged in sequence, the power section is used as a micro wind speed source controller for providing micro wind speed; the rectification section rectifies the micro wind speed; the test section serves as a micro-wind-speed sensor calibration section, and a standard anemometer and a tested micro-wind-speed sensor are arranged; the protection section is used for isolating the influence of environment pressure change on a flow field in the device; the micro-wind speed detection system receives wind speed information collected by the standard anemometer of the test section and controls the micro-wind speed provided by the power section, so that the standard anemometer reaches the micro-wind speed detection precision, and calibration of the detected micro-wind speed sensor is realized. The device and the method are based on the wavelength-wind speed conversion principle, and the measurement precision of 0.002 m / s can be realized by virtue of the ultrahigh resolution of 1pm of a demodulation module used by a standard anemometer.

Description

Technical Field

[0001] The present invention relates to the technical field of wind speed measurement, and in particular to a micro wind speed sensor calibration device and method. Background Art

[0002] In many fields such as weather forecasting, agricultural production, biomedicine, industrial development, and military industry, gas flow rates below 2m / s are usually called breezes. For a long time, the calibration of breeze speed sensors has not been fully solved. In particular, for some specific environments where wind speed detection is lower than 0.5m / s, such as coal mine working faces and goafs, higher requirements are placed on breeze detection accuracy, so the accuracy of wind speed sensors has become an important indicator.

[0003] At present, the calibration method of micro-anemometer is mainly based on the laser Doppler principle. The Chinese invention patent application number 202111291222.X, entitled "A device and method for calibrating a micro-anemometer using laser measurement", introduces a calibration device for an anemometer. The invention uses a laser Doppler anemometer to illuminate a transparent air duct and measure the tracer particle smoke moving with the wind in the air duct, which is the wind speed in the air duct. This is used as the wind speed calibration value, and then compared with the wind speed obtained by the anemometer probe after the blockage ratio calculation and correction, so as to show the accuracy of the anemometer.

[0004] Laser Doppler equipment is complex and expensive. The core laser is currently still imported from abroad, and the installation angle of the laser and the supporting calibration equipment have strict requirements. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a micro wind speed sensor calibration device and method in view of the above-mentioned deficiencies in the prior art, so as to realize the calibration of the micro wind speed sensor.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0007] On the one hand, the present invention provides a micro wind speed sensor calibration device, comprising a power section, a rectification section, a test section, a protection section and a micro wind speed detection system arranged in sequence; the power section acts as a micro wind speed source controller to provide micro wind speed; the rectification section rectifies the micro wind speed; the test section acts as a micro wind speed sensor calibration section, in which a standard anemometer and a micro wind speed sensor to be measured are arranged; the protection section is used to isolate the influence of changes in ambient air pressure on the flow field in the device; the micro wind speed detection system receives wind speed information collected by the standard anemometer in the test section, controls the micro wind speed provided by the power section, enables the standard anemometer to achieve micro wind speed detection accuracy, and realizes calibration of the micro wind speed sensor to be measured.

[0008] Furthermore, the rectification section includes a transition section, a stable section and a contraction section; the transition section adopts a bell-mouth design to achieve the first rectification of the micro wind speed; a honeycomb rectifier is arranged inside the stable section to achieve the second rectification of the micro wind speed; the contraction section adopts a Venturi design to achieve the third rectification of the micro wind speed.

[0009] Furthermore, the test section is provided with two fixtures separated by a set distance, and the standard anemometer and the measured micro wind speed sensor are installed in the test section through the two fixtures.

[0010] Furthermore, the power section adopts a servo motor as a micro wind speed source controller, and adopts a pressure-delivery method to provide micro wind speed; the servo motor has a speed range of 0r / min-2000r / min and a step frequency of 1r / min according to needs, achieving a control range of 1:2000. For the wind speed detection range of 2m / s, the wind speed resolution reaches 0.001m / s.

[0011] Furthermore, a multi-layer damping net is provided in the protection section to isolate the influence of the change of the ambient air pressure on the flow field in the device.

[0012] Furthermore, the test section uses an optical fiber hot wire micro wind speed sensor as a standard anemometer; the optical fiber thermal micro wind speed sensor includes an optical fiber hot wire micro wind speed sensor probe and a micro wind speed demodulation module; the optical fiber hot wire micro wind speed sensor probe is connected to the micro wind speed demodulation module to achieve data transmission; the optical fiber hot wire micro wind speed sensor probe uses optical principles to transmit signals through optical fibers to achieve wind speed measurement; the micro wind speed demodulation module processes the optical signal transmitted by the optical fiber hot wire micro wind speed sensor probe, demodulates the wavelength data, and transmits it to the micro wind speed detection system;

[0013] Furthermore, the wavelength drift of the optical fiber hot wire micro wind speed probe is 1nm when the wind speed range is 0m / s-2m / s, the demodulation accuracy of the micro wind speed demodulation module is 1pm, and the measurement accuracy of the standard anemometer is 0.002m / s.

[0014] Furthermore, the micro-wind speed calibration system achieves a step size of 1 r / min by controlling the speed of the servo motor, so that the wind speed resolution of the optical fiber thermal micro-wind speed sensor reaches 0.001 m / s; by reading the wavelength data demodulated by the micro-wind speed demodulation module, the correspondence between wind speed and wavelength drift is obtained according to the correspondence between wavelength drift and micro-wind speed, thereby achieving micro-wind speed detection with a detection accuracy of 0.002 m / s.

[0015] Furthermore, the calculation method for the breeze speed calibration system to perform breeze detection is:

[0016] According to the fact that the heat generated by the internal heat source of the optical fiber thermal micro-wind speed sensor is equal to the heat lost by convection, the balanced power of the optical fiber hot wire micro-wind speed sensor probe can be obtained as shown in the following formula:

[0017] Q=hA△t

[0018] Where Q represents the balanced power of the optical fiber hot wire micro wind speed sensor probe, h represents the convective heat transfer coefficient of the air, A represents the windward cross-sectional area of ​​the optical fiber hot wire micro wind speed sensor probe, which is related to the probe structure, and △t represents the temperature difference between the optical fiber hot wire micro wind speed sensor probe and the ambient temperature;

[0019] Based on the optical fiber sensing principle, the real-time wavelength data demodulated by the micro-wind speed demodulation module is expressed as follows:

[0020] λ=λ0+k△t

[0021] Wherein, λ represents the real-time wavelength data demodulated by the micro-wind speed demodulation module, λ0 represents the initial wavelength, and k represents the temperature coefficient of the optical fiber hot wire micro-wind speed sensor probe;

[0022] Then the relationship between wavelength change and wind speed is derived:

[0023]

[0024] Among them, A c and B c are the coefficients of the optical fiber thermal micro wind speed sensor, △λ represents the difference between the wavelength value at different wind speeds and the initial wavelength value, v is the kinematic viscosity, l is the characteristic length of the optical fiber thermal micro wind speed sensor; the coefficient A of the optical fiber thermal micro wind speed sensor is c and B c Based on the Nusselt number, Reynolds number and Prandtl number, obtained through multiple experiments;

[0025] On the other hand, the present invention also provides a micro wind speed sensor calibration method, comprising:

[0026] Insert the optical fiber hot wire micro wind speed sensor probe as the standard anemometer and the wind speed sensor to be measured into the two fixtures of the test section respectively;

[0027] The micro wind speed detection system reads the wavelength data demodulated by the micro wind speed demodulation module of the optical fiber hot wire micro wind speed sensor and performs wind speed zero value calibration;

[0028] Start the servo motor and set the servo motor speed through the micro-wind speed detection system. When the speed stabilizes, the micro-wind speed detection system collects the wavelength data demodulated by the micro-wind speed demodulation module.

[0029] The micro wind speed detection system converts the wavelength data demodulated by the micro wind speed demodulation module into wind speed values, which are then displayed and saved in real time;

[0030] The wind speed value measured by the micro wind speed sensor under test is read and recorded in the micro wind speed detection system. The wind speed value measured by the micro wind speed sensor under test is compared with the wind speed value collected by the optical fiber thermal micro wind speed sensor to realize the calibration of the micro wind speed sensor under test.

[0031] The beneficial effects of the above-mentioned technical solution are as follows: The present invention provides a micro-wind speed sensor calibration device and method. This device uses a servo motor as the core wind source, achieves precise rotational speed adjustment through a micro-wind speed detection system, and outputs a stable airflow in conjunction with a three-stage rectification structure consisting of a transition section, a stabilization section, and a contraction section. The fiber optic hot wire micro-wind speed sensor, serving as a standard anemometer, utilizes the wavelength-to-wind speed conversion principle and leverages the ultra-high resolution of its demodulation module (1pm) to achieve a measurement accuracy of 0.002m / s. This meets the needs for high-precision micro-wind speed calibration in fields such as meteorological monitoring, environmental science, and aerospace.

[0032] The device is highly integrated, has simple supporting devices, low cost, and can realize the localization of core detection components. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 A schematic structural diagram of a micro wind speed sensor calibration device provided by an embodiment of the present invention;

[0034] Figure 2 This is a flow chart of a micro wind speed sensor calibration method provided by an embodiment of the present invention.

[0035] In the figure: 1. Power section; 2. Transition section; 3. Stabilization section; 4. Rectifier; 5. Contraction section; 6. Test section; 7. Protection section; 8. Fiber optic hot wire micro wind speed sensor probe; 9. Optical cable; 10. Micro wind speed demodulation module; 11. First fixture; 12. Second fixture; 13. Multi-layer damping structure. DETAILED DESCRIPTION

[0036] The following embodiments of the present invention are described in further detail with reference to the accompanying drawings and examples. The following examples are used to illustrate the present invention but are not intended to limit the scope of the present invention.

[0037] In this embodiment, a micro wind speed sensor calibration device, such as Figure 1As shown, it includes a power section 1, a rectification section, a test section 6, a protection section 7 and a micro-wind speed detection system arranged in sequence; the power section 1 provides micro-wind speed as a micro-wind speed source controller; the rectification section rectifies the micro-wind speed, and includes a transition section 2, a stable section 3 and a contraction section 5; the transition section 2 adopts a trumpet-shaped design to achieve the first rectification of the micro-wind speed; a honeycomb rectifier is arranged inside the stable section 3 to achieve the second rectification of the micro-wind speed; the contraction section 5 adopts a Venturi design to achieve the third rectification of the micro-wind speed; the test section 6 serves as a micro-wind speed sensor calibration section, and a standard anemometer and a micro-wind speed sensor to be measured are arranged; the protection section 7 is used to isolate the influence of environmental air pressure changes on the flow field in the device; the micro-wind speed detection system receives the wind speed information collected by the standard anemometer in the test section 6, controls the micro-wind speed provided by the power section 1, enables the standard anemometer to achieve micro-wind speed detection accuracy, and realizes calibration of the micro-wind speed sensor to be measured.

[0038] In this embodiment, the test section 6 is provided with a first clamp 11 and a second clamp 12 spaced a certain distance apart, and the standard anemometer and the measured micro wind speed sensor are installed in the test section 6 through the first clamp 11 and the second clamp 12 respectively.

[0039] The power section 1 adopts a servo motor as a micro wind speed source controller and adopts a pressure-feeding method to provide micro wind speed; the servo motor has a speed range of 0r / min-2000r / min and a step frequency of 1r / min according to needs, achieving a control range of 1:2000. For the wind speed detection range of 2m / s, the wind speed resolution reaches 0.001m / s.

[0040] The test section 6 uses a fiber optic hot wire micro wind speed sensor as a standard anemometer; the fiber optic thermal micro wind speed sensor includes a fiber optic hot wire micro wind speed sensor probe 8 and a micro wind speed demodulation module 10; the fiber optic hot wire micro wind speed sensor probe 8 is connected to the micro wind speed demodulation module 10 to achieve data transmission; the fiber optic hot wire micro wind speed sensor probe 8 uses optical principles to transmit signals through optical fibers to achieve wind speed measurement; the micro wind speed demodulation module 10 processes the optical signal transmitted by the fiber optic hot wire micro wind speed sensor probe 8, demodulates the wavelength data, and transmits it to the micro wind speed detection system;

[0041] The wavelength drift of the optical fiber hot wire micro wind speed probe 8 is 1 nm when the wind speed range is 0 m / s-2 m / s, the demodulation accuracy of the micro wind speed demodulation module 10 is 1 pm, and the measurement accuracy of the standard anemometer is 0.002 m / s.

[0042] In this embodiment, the servo motor adopts a high-torque, high-precision model and is fixed inside the power section 1 by a customized rigid mounting base to ensure stability and low vibration characteristics during operation. The power section 1 and the transition section 2 are fastened together by bolts, and a nitrile rubber gasket is embedded in the connection surface to form a reliable sealing structure to prevent airflow leakage. The transition section 2 is designed as a gradually expanding bell-mouth shape. Its unique geometric shape can effectively guide the smooth diffusion of the airflow, realize the first wind speed rectification during the operation of the device, and reduce the turbulence of the airflow. The transition section 2 and the stabilizing section 3 are also connected by bolts, and a double-layer sealing gasket is added at the connection point to further improve the sealing performance. The core component of the stabilizing section 3 is the multi-layer rectifier 4. Inside the rectifier 4, 5 layers of honeycomb structure are arranged in sequence along the direction of airflow. The diameter of the honeycomb gradually decreases and becomes finer. Through this aperture gradient design, the secondary refined rectification of the airflow is achieved, and the uniformity and stability of the airflow are improved to a higher level. The connection between the contraction section 5 and the stable section 3 utilizes a proven bolt-and-gasket sealing scheme. The contraction section 5 employs a classic Venturi structure with a contraction ratio of 1:3. Utilizing fluid dynamics, the airflow undergoes a third rectification, achieving a stable, uniform laminar flow before entering the test section 6. The test section 6 and contraction section 5 are secured together using flanges and bolts, with a fluororubber gasket embedded in the connection to ensure a secure seal. A first clamp 11 and a second clamp 12 are installed at the center of the test section 6. The fiber-optic hot-wire micro-wind velocity sensor probe 8 is inserted into the first clamp 11 using a threaded insertion method, ensuring the probe is perpendicular to the airflow. The second clamp 12 features a quick-release design, facilitating the rapid replacement of different wind velocity sensors. Fluid dynamics simulations have verified that the probe, with a diameter of only 1 mm, causes negligible disturbance to the flow field in the test section 6. The fiber-optic hot-wire micro-wind velocity sensor probe 8 is connected to the micro-wind velocity demodulation module 10 via an optical cable 9, which is resistant to electromagnetic interference, ensuring accurate and stable data transmission. The same bolt sealing connection process is used between the protective section 7 and the test section 6. A multi-layer damping structure 13 is set inside the protective section 7. The damping structure 13 is composed of polyurethane sponges and metal meshes of different densities alternately stacked, which can effectively isolate interference factors such as external environmental pressure fluctuations and mechanical vibrations, providing a stable testing environment for the test section 6 and ensuring the reliability of wind speed measurement data.

[0043] The micro wind speed calibration system achieves a step size of 1 r / min by controlling the rotation speed of the servo motor, so that the wind speed resolution of the optical fiber thermal micro wind speed sensor reaches 0.001 m / s; by reading the wavelength data demodulated by the micro wind speed demodulation module 10, the corresponding relationship between wind speed and wavelength drift is obtained according to the correspondence between wavelength drift and micro wind speed, thereby achieving micro wind speed detection with a detection accuracy of 0.002 m / s.

[0044] The calculation method for breeze detection by the breeze speed calibration system is:

[0045] According to the fact that the heat generated by the internal heat source of the optical fiber thermal micro-wind speed sensor is equal to the heat lost by convection, the balanced power of the optical fiber thermal wire micro-wind speed sensor probe 8 can be obtained as shown in the following formula:

[0046] Q=hA△t

[0047] Wherein, Q represents the balanced power of the optical fiber hot wire micro wind speed sensor probe 8, h represents the convection heat transfer coefficient of the air, A represents the windward cross-sectional area of ​​the optical fiber hot wire micro wind speed sensor probe 8, which is related to the probe structure, and Δt represents the temperature difference between the optical fiber hot wire micro wind speed sensor probe 8 and the ambient temperature;

[0048] Based on the optical fiber sensing principle, the real-time wavelength data demodulated by the micro-wind speed demodulation module 10 is expressed as follows:

[0049] λ=λ0+k△t

[0050] Wherein, λ represents the real-time wavelength data demodulated by the micro-wind speed demodulation module 10, λ0 represents the initial wavelength, and k represents the temperature coefficient of the optical fiber hot wire micro-wind speed sensor probe 8;

[0051] Then the relationship between wavelength change and wind speed is derived:

[0052]

[0053] Among them, A c and B c are the coefficients of the optical fiber thermal micro wind speed sensor, △λ represents the difference between the wavelength value at different wind speeds and the initial wavelength value, v is the kinematic viscosity, l is the characteristic length of the optical fiber thermal micro wind speed sensor; the coefficient A of the optical fiber thermal micro wind speed sensor is c and B c Based on the Nusselt number, Reynolds number and Prandtl number, obtained through multiple experiments;

[0054] According to the principles of fluid mechanics and heat transfer, the Nusselt number, Reynolds number, and Prandtl number are shown in the following formulas:

[0055] N u =C*Re n *Pr 1 / 3

[0056]

[0057] Among them, N u, Re, and Pr are dimensionless constants, namely the Nusselt number, Reynolds number, and Prandtl number, respectively (in this embodiment, the change in the Prandtl number of air is almost negligible, and Pr is taken as 0.7); u, v represent the fluid velocity (i.e., wind speed) and kinematic viscosity (constants at room temperature), respectively; l is the characteristic length of the optical fiber hot wire micro-wind speed sensor (a known constant); in this embodiment, according to the structure of the sensor, l is 1 mm; C and n are constants related to the Reynolds number; and α is the thermal conductivity of the fluid.

[0058] In this embodiment, a micro wind speed sensor calibration method is as follows: Figure 2 Shown, including:

[0059] Insert the optical fiber hot wire micro wind speed sensor probe 8 as a standard anemometer and the wind speed sensor to be measured into the first clamp 11 and the second clamp 12 of the test section 6 respectively;

[0060] The micro wind speed detection system reads the wavelength data of the micro wind speed demodulation module 10 of the optical fiber hot wire micro wind speed sensor and performs wind speed zero value calibration;

[0061] In the initial state, the servo motor speed is zero, indicating no wind. In this state, the initial wavelength varies each time due to varying ambient temperatures during actual testing. Therefore, the initial wavelength of the current test is read by the micro-wind speed demodulation module 10. The micro-wind speed detection system then automatically reads the data from the micro-wind speed demodulation module 10 and uses it as the initial wavelength for zero-value wind speed calibration.

[0062] The servo motor is started and the servo motor speed is set by the micro-wind speed detection system. When the speed is stable, the micro-wind speed detection system collects the wavelength data demodulated by the micro-wind speed demodulation module 10;

[0063] The micro wind speed detection system converts the wavelength data demodulated by the micro wind speed demodulation module 10 into wind speed values, which are then displayed synchronously in digital and curve form on the display and saved in real time;

[0064] The wind speed value measured by the micro wind speed sensor under test is read and recorded in the micro wind speed detection system. The wind speed value measured by the micro wind speed sensor under test is compared with the wind speed value collected by the optical fiber thermal micro wind speed sensor to realize the calibration of the micro wind speed sensor under test.

[0065] In this embodiment, the micro wind speed detection system automatically calculates the measurement deviation between the optical fiber hot wire micro wind speed sensor probe 8 and the wind speed sensor being measured, and generates a deviation analysis report; the motor speed is increased to 1000rpm, 1500rpm, and 2000rpm in turn, and the above test steps are repeated to cover the micro wind speed measurement range of 0.5m / s-10m / s; after completing all test points, the system generates a complete comparative test report, which includes the measurement values, deviation values, linearity analysis, etc. of each wind speed point, and calibrates the micro wind speed sensor being measured.

[0066] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope defined by the claims of the present invention.

Claims

1. A micro wind speed sensor calibration device, characterized by: The device comprises a power section, a rectification section, a test section, a protection section and a micro-wind speed detection system which are arranged in sequence; the power section acts as a micro-wind speed source controller to provide micro-wind speed; the rectification section rectifies the micro-wind speed; the test section acts as a micro-wind speed sensor calibration section, in which a standard anemometer and a micro-wind speed sensor to be measured are arranged; the protection section is used to isolate the influence of changes in ambient air pressure on the flow field in the device; the micro-wind speed detection system receives wind speed information collected by the standard anemometer in the test section, controls the micro-wind speed provided by the power section, enables the standard anemometer to achieve micro-wind speed detection accuracy, and realizes calibration of the micro-wind speed sensor to be measured.

2. A micro wind speed sensor calibration device according to claim 1, characterized in that: The rectification section includes a transition section, a stable section and a contraction section; the transition section adopts a bell-mouth design to achieve the first rectification of the micro wind speed; a honeycomb rectifier is arranged inside the stable section to achieve the second rectification of the micro wind speed; the contraction section adopts a Venturi design to achieve the third rectification of the micro wind speed.

3. A micro wind speed sensor calibration device according to claim 2, characterized in that: The test section is provided with two fixtures separated by a set distance, and the standard anemometer and the measured micro wind speed sensor are installed in the test section through the two fixtures.

4. A micro wind speed sensor calibration device according to claim 1, characterized in that: The power section adopts a servo motor as a micro wind speed source controller and adopts a pressure-delivery method to provide micro wind speed; the servo motor has a speed range of 0r / min-2000r / min and a step frequency of 1r / min according to needs, achieving a control range of 1:2000. For the wind speed detection range of 2m / s, the wind speed resolution reaches 0.001m / s.

5. The micro wind speed sensor calibration device according to claim 1, characterized in that: A multi-layer damping net is arranged in the protection section to isolate the influence of the ambient air pressure change on the flow field in the device.

6. A micro wind speed sensor calibration device according to claim 4, characterized in that: The test section uses an optical fiber hot wire micro wind speed sensor as a standard anemometer; the optical fiber thermal micro wind speed sensor includes an optical fiber hot wire micro wind speed sensor probe and a micro wind speed demodulation module; The optical fiber hot wire micro wind speed sensor probe is connected to the micro wind speed demodulation module to realize data transmission; the optical fiber hot wire micro wind speed sensor probe uses optical principles to transmit signals through optical fibers to realize wind speed measurement; the micro wind speed demodulation module processes the optical signal transmitted by the optical fiber hot wire micro wind speed sensor probe, demodulates the wavelength data, and transmits it to the micro wind speed detection system.

7. A micro wind speed sensor calibration device according to claim 6, characterized in that: The wavelength drift of the optical fiber hot wire micro wind speed probe is 1nm when the wind speed range is 0m / s-2m / s, the demodulation accuracy of the micro wind speed demodulation module is 1pm, and the measurement accuracy of the standard anemometer is 0.002m / s.

8. A micro wind speed sensor calibration device according to claim 7, characterized in that: The micro wind speed calibration system achieves a step size of 1 r / min by controlling the servo motor speed, so that the wind speed resolution of the optical fiber thermal micro wind speed sensor reaches 0.001 m / s; By reading the wavelength data demodulated by the micro-wind speed demodulation module and according to the correspondence between wavelength drift and micro-wind speed, the corresponding relationship between wind speed and wavelength drift is obtained, and micro-wind speed detection with a detection accuracy of 0.002m / s is achieved.

9. A micro wind speed sensor calibration device according to claim 8, characterized in that: The calculation method for the breeze speed calibration system to perform breeze detection is: According to the fact that the heat generated by the internal heat source of the optical fiber thermal micro-wind speed sensor is equal to the heat lost by convection, the balanced power of the optical fiber hot wire micro-wind speed sensor probe can be obtained as shown in the following formula: Q=hA△t Where Q represents the balanced power of the optical fiber hot wire micro wind speed sensor probe, h represents the convective heat transfer coefficient of the air, A represents the windward cross-sectional area of ​​the optical fiber hot wire micro wind speed sensor probe, which is related to the probe structure, and △t represents the temperature difference between the optical fiber hot wire micro wind speed sensor probe and the ambient temperature; Based on the optical fiber sensing principle, the real-time wavelength data demodulated by the micro-wind speed demodulation module is expressed as follows: λ=λ0+k△t Wherein, λ represents the real-time wavelength data demodulated by the micro-wind speed demodulation module, λ0 represents the initial wavelength, and k represents the temperature coefficient of the optical fiber hot wire micro-wind speed sensor probe; Then the relationship between wavelength change and wind speed is derived: Among them, A c and B c are the coefficients of the optical fiber thermal micro wind speed sensor, △λ represents the difference between the wavelength value at different wind speeds and the initial wavelength value, v is the kinematic viscosity, l is the characteristic length of the optical fiber thermal micro wind speed sensor; the coefficient A of the optical fiber thermal micro wind speed sensor is c and B c Based on the Nusselt number, Reynolds number and Prandtl number, obtained through multiple experiments.

10. A micro wind speed sensor calibration method, implemented based on the micro wind speed sensor calibration device according to claim 6, characterized in that: include: Insert the optical fiber hot wire micro wind speed sensor probe as the standard anemometer and the wind speed sensor to be measured into the two fixtures of the test section respectively; The micro wind speed detection system reads the wavelength data demodulated by the micro wind speed demodulation module of the optical fiber hot wire micro wind speed sensor and performs wind speed zero value calibration; Start the servo motor and set the servo motor speed through the micro-wind speed detection system. When the speed stabilizes, the micro-wind speed detection system collects the wavelength data demodulated by the micro-wind speed demodulation module. The micro wind speed detection system converts the wavelength data demodulated by the micro wind speed demodulation module into wind speed values, which are then displayed and saved in real time; The wind speed value measured by the micro wind speed sensor under test is read and recorded in the micro wind speed detection system. The wind speed value measured by the micro wind speed sensor under test is compared with the wind speed value collected by the optical fiber thermal micro wind speed sensor to realize the calibration of the micro wind speed sensor under test.

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