CN206193025U - Passive formula air speed measuring device of optic fibre - Google Patents

Abstract

The utility model relates to the technical field of wind speed detection, in particular to an optical fiber passive wind speed measuring device, which includes a fixed chassis, a wind cup structure and an optical fiber grating strain sensor; The central rotating shaft is connected with the wind cup structure and the rotating disc, and the rotating disc is provided with a magnet; the fiber grating strain sensor is arranged on the cantilever of the cantilever beam, and the free cantilever beam The end is provided with a magnet that can be opposite to the magnet of the rotating disc in the axial direction. The utility model can reduce the abrasion caused by the long-term operation of the hard connection device; through the detection of the strain frequency, the influence of temperature on the measurement result can be eliminated, and the accuracy and reliability of wind speed measurement can be improved.

Description

An optical fiber passive wind speed measuring device

technical field

The utility model relates to the technical field of wind speed detection based on fiber grating sensing technology, in particular to an optical fiber passive wind speed measuring device.

Background technique

At present, instruments for measuring air velocity are widely used in various fields, such as electric power, steel, petrochemical, energy-saving and other industries. In daily life, many industries need to use wind speed monitoring devices, such as fan manufacturing, sea fishing, ventilation and heating Systems, etc., all need to use wind speed measuring devices to measure wind speed, wind temperature, and air volume. The existing wind speed measurement devices are divided into two categories: active measurement devices and passive measurement devices, such as electronic wind cup type, hot wire type, ultrasonic type, Doppler frequency shift type and Pitot tube type are all active measurement; Fiber Bragg grating contact measurement of wind speed. Electronic wind speed measurement technology is more commonly used in active measurement devices. Its characteristics based on electronic information processing technology are destined to be subject to active power supply, susceptible to electromagnetic interference, unstable remote signal transmission, and limited data transmission capacity. Restricted by factors such as these, the limitations of its application environment are limited, especially in some strong magnetic and strong electric environments, the safety and reliability of electronic wind speed measurement equipment have received great challenges.

The emergence of fiber grating sensing technology, in addition to breaking through the limitations of active power supply and interference factors such as strong electricity and strong magnetism, also has the advantages of high sensitivity, small size, light weight, and low cost, and has intrinsic self-coherence. Strong capability and the unique advantages of using multiplexing technology to realize multi-point multiplexing and multi-parameter distributed differential measurement on one optical fiber. Although the existing passive on-line wind speed monitoring method of fiber grating sensing technology can make up for the deficiency of the inclination angle measurement method of the existing electronic wind speed measuring device, which is beneficial to computer remote monitoring and diversified analysis, but the existing fiber grating sensor The passive online wind speed monitoring device of the technology adopts the contact type, and long-term contact friction will cause wear and aging of the wind speed monitoring device, affecting the normal operation of the device; and, the existing passive online wind speed monitoring device of the fiber grating sensing technology The wind speed is measured by obtaining wavelength data, and during the wind speed monitoring process, the temperature around the fiber grating strain sensor will change, and the temperature change will affect the fiber grating strain sensor, that is, the central wavelength will be affected, so the wind speed cannot be guaranteed Measurement accuracy and reliability.

Utility model content

(1) Technical problems to be solved

The utility model provides an optical fiber passive wind speed measuring device, which is used to solve the problems of wear and aging in the existing optical fiber grating wind speed measuring device and the problem that the accuracy and reliability of wind speed measurement are reduced by temperature changes.

(2) Technical solutions

In order to solve the above technical problems, the utility model provides an optical fiber passive wind speed measuring device, which includes a fixed chassis, a wind cup structure and a fiber grating strain sensor; the fixed chassis is provided with a central shaft that can rotate relative to the fixed chassis , the wind cup structure and the rotating disk are connected to the central shaft, and the rotating disk is provided with a magnet; the fiber grating strain sensor is arranged on the cantilever of the cantilever beam, and the free end of the cantilever beam is arranged There are magnets capable of being axially opposed to the magnets of the rotating disc.

Wherein, the central rotating shaft is arranged on the fixed chassis through a bearing fixing device.

Wherein, the central rotating shaft runs through the fixed chassis and the bearing fixing device, one end of the central rotating shaft is connected to the wind cup structure, and the other end of the central rotating shaft is fixed in the central area of the rotating disc.

Wherein, the cantilever beam is arranged on the fixed chassis.

Wherein, the fiber grating strain sensor is welded on the cantilever beam.

Wherein, the wind cup structure is a three-cup wind cup structure.

Wherein, the wind cup of the wind cup structure is semicircular.

Wherein, the material of the wind cup structure is aluminum.

Wherein, the material of the rotating disc is aluminum.

(3) Beneficial effects

Compared with the prior art, the optical fiber passive wind speed measuring device provided by the utility model has the following beneficial effects:

1. The optical fiber passive wind speed measurement device of the present invention adopts the method of setting magnets at the corresponding positions of the rotating disk and the cantilever beam structure, and quantifies the wind speed into a periodically changing stress by using non-contact magnetic force. On the one hand, this design can reduce the wear and tear caused by the long-term operation of the hard connection device. On the other hand, it can eliminate the influence of temperature changes on the measurement results by detecting the strain frequency, which greatly improves the accuracy and reliability of wind speed measurement. ;

2. The optical fiber passive wind speed measuring device of the present invention adopts a semicircular wind cup, which can increase the wind receiving area, increase the wind receiving force, and effectively increase the starting wind speed; Disc, to avoid the performance deterioration of the device caused by magnetic interference; the use of bearings to fix the central shaft can eliminate the friction between the central shaft and the fixed structure, reduce the starting wind speed of the device, and eliminate the friction caused by friction to the parts of the device. damage, thereby improving the performance of the device and ensuring the flexibility and practicability of the device.

Description of drawings

Fig. 1 is the schematic structural diagram of the optical fiber passive wind speed measuring device provided by the embodiment of the present invention;

In the figure, 1: wind cup structure; 2: bearing fixed structure; 3: central shaft; 4: chassis; 5: rotating disc; 6: magnet; 7: cantilever beam; 8: fiber grating strain sensor.

detailed description

In order to facilitate the understanding of the utility model, the utility model will be described more fully below with reference to the relevant drawings. Preferred embodiments of the utility model are provided in the accompanying drawings. The above are only preferred embodiments of the present utility model, and are not intended to limit the patent scope of the present utility model. Any equivalent structure or equivalent process conversion made by using the description of the utility model and the contents of the accompanying drawings, or directly or indirectly used in other related All technical fields are all included in the scope of patent protection of the utility model in the same way.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field of this invention. The terminology used herein in the description of the utility model is only for the purpose of describing specific implementations, and is not intended to limit the utility model. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

The utility model provides an optical fiber passive wind speed measuring device, which is used to solve the problems of wear and aging in the existing optical fiber grating wind speed measuring device, and avoid the influence of temperature changes on reducing the accuracy and reliability of wind speed measurement.

As shown in Figure 1, an optical fiber passive wind speed measuring device is provided in the embodiment of the present utility model, including a fixed chassis 4, a wind cup structure 1 and a fiber grating strain sensor 8; the fixed chassis 4 is provided with a relatively fixed chassis 4 The rotating central shaft 3 is connected with the wind cup structure 1 and the rotating disc 5, and the rotating disc 5 is provided with a magnet; the fiber grating strain sensor 8 is arranged on the cantilever of the cantilever beam 7, and the free cantilever beam 7 The end is provided with a magnet capable of opposing the magnet of the rotating disk 5 in the axial direction. When the wind blows the wind cup structure 1 to drive the central rotating shaft 3 to rotate, the rotating disc 5 fixedly connected to the central rotating shaft 3 also rotates thereupon, and the magnets on the rotating disc 5 and the magnets at the free ends of the cantilever beam 7 can be positioned at a certain position. For a moment, they correspond to each other in the axial direction and interact with each other to generate non-contact magnetic force. The fiber grating strain sensor 8 on the cantilever beam 7 is subjected to force, thereby changing the central wavelength of the fiber grating, and the rotating disk 5 is driven by the wind to rotate In the process, the strain frequency can be obtained by detecting the peak value of the strain waveform per unit time, and then the real-time wind speed can be deduced according to the relationship between the strain and the wind speed.

The utility model adopts the arrangement of magnets at corresponding positions on the rotating disk 5 and the cantilever beam 7, and can cleverly quantify the wind speed into a periodically changing stress by utilizing the non-contact magnetic force. The final real-time wind speed is measured by detecting the frequency of stress changes (the number of peak values of the strain waveform per unit time). The detection eliminates the influence of temperature changes on the measurement results, which can improve the accuracy and reliability of wind speed measurement.

It can be understood that, the fiber Bragg grating strain sensor 8 in this embodiment is a fiber Bragg grating (Fiber Bragg Grating FBG for short) strain sensor. The optical fiber grating strain sensor used in the utility model has the characteristics of realizing passive operation, resisting strong electric and strong magnetic interference, small volume, light weight, corrosion resistance and high temperature resistance.

In this embodiment, the central rotating shaft 3 is arranged on the fixed chassis 4 through the bearing fixing device 2 . The central shaft 3 runs through the fixed chassis 4 and the bearing fixing device 2 , and the bearing fixing device 2 is connected to the bottom of the fixed chassis 4 , so that the central rotating shaft 3 can be arranged on the fixed chassis 4 through the bearing fixing device 2 . The method of fixing the central rotating shaft 3 with bearings can eliminate the friction between the central rotating shaft 3 and the fixed structure, greatly reduce the starting wind speed of the device, and can eliminate the damage caused by friction to the parts of the device, thereby improving the performance of the device. Ensure the flexibility and practicality of the device.

In this embodiment, the bottom end of the central rotating shaft 3 is connected to the wind cup structure 1 , and the top end of the central rotating shaft 3 is fixed on the central area of the rotating disk 5 . The bottom of the rotating disc is provided with a magnet, and the cantilever beam 7 is arranged near the edge of the fixed chassis 4, and the magnet is set above the free end of the cantilever beam 7, and the magnets at two places can be corresponding to the axial direction.

In this embodiment, the upper surface of the cantilever of the cantilever beam 7 is welded with a fiber grating strain sensor 8. During the rotation process, the magnet at the free end of the cantilever beam 7 can be aligned with the magnet at the bottom of the rotating disk 5, so that the magnets at the two places interact , in order to produce a more obvious magnetic force, a certain distance should be kept when the two magnets are aligned, that is, a certain distance should be kept between the rotating disc and the fixed chassis in the axial direction to ensure sufficient magnetic force. The magnet is affected by the magnetic force of the magnet on the turntable, which drives the deformation of the free end of the cantilever beam. The change of the free end of the cantilever beam will drive the drift of the center wavelength of the fiber grating. Every time the rotating disk rotates, the center wavelength of the fiber grating will drift for a period.

It can be understood that the wind cup structure 1 is a multi-cup type wind cup structure, and in this embodiment, the wind cup structure 1 adopts a three-cup type wind cup structure.

In this embodiment, the wind cup of the wind cup structure 1 is semicircular, and this structure can increase the wind receiving area, increase the wind receiving force, and effectively increase the starting wind speed.

In this embodiment, the material of the wind cup structure 1 is aluminum. Since the aluminum material is light and does not rust, the use of an aluminum wind cup structure can avoid the problem of long-term exposure of the wind cup to rust outside, and can also increase The flexibility of wind cup rotation.

In this embodiment, the material of the rotating disk 5 is aluminum, which is light in weight and has no magnetism. It will be more flexible during the rotation and will not be affected by the magnet fixed at the end of the cantilever beam below, which avoids magnetic interference. Performance degradation caused by the device.

The specific implementation principle and working method of the optical fiber passive wind speed measuring device provided by the utility model are as follows:

When the environment where the optical fiber passive wind speed measuring device is located is windy, the wind cup will rotate under the action of the wind, and the wind cup will drive the rotating disc 5 to rotate at the speed of the wind cup through the central rotating shaft 3 . The free end of the cantilever beam 7 and the bottom surface of the rotating disc 5 are inlaid with fixed magnets. When the magnet on the bottom surface of the rotating disc 5 and the magnet at the free end of the cantilever beam 7 turn to be opposite to each other in the axial direction, the two magnets interact to make the cantilever The cantilever of the beam 7 is deformed, the fiber grating on the cantilever 7 is subjected to force, and the center wavelength drifts, and the information is collected by the demodulator, and the data is stored in the database for program processing. A straining process occurs with each revolution of the wind cup. The greater the wind speed, the greater the rotation rate of the wind cup, that is, the higher the rotation speed, the more times the fiber grating will be strained per unit time, that is, the higher the frequency of the fiber grating being subjected to tensile or compressive strain, through monitoring The real-time wind speed can be calculated by the strain frequency of the fiber grating per unit time.

When the two magnets face each other in the axial direction, the interaction force generated can be repulsive force or attractive force, both of which can make the central wavelength shift, which can realize the detection of the strain frequency.

When the axial distance between the cantilever beam 7 and the rotating disc 5 makes the two magnets produce repulsion, the upper surface of the cantilever beam deforms downward, resulting in tensile deformation, and the fiber grating installed on the upper surface of the cantilever beam 7 is subjected to tensile force Function, the central wavelength of the fiber grating is shifted to a large extent, the information is collected by the demodulator, and the data is stored in the database for program processing.

When the axial distance between the cantilever beam 7 and the rotating disk 5 makes the two magnets attract, the upper surface of the cantilever beam is deformed upwards, resulting in compression deformation, and the fiber grating installed on the upper surface of the cantilever beam 7 is subjected to the compressive force. The central wavelength of the grating is shifted toward the small, and the information is collected by the demodulator, and the data is stored in the database for program processing.

The utility model is a passive online wind speed monitoring device based on an optical fiber grating sensor, which cleverly converts the force from the wind on the wind cup into the non-contact magnetic force at the end of the strain cantilever beam, causing the cantilever equipped with the optical fiber grating strain sensor Beam strain, so as to obtain the corresponding data information. This design not only reduces the device damage caused by friction between devices, but also overcomes the influence of temperature changes on the central wavelength, making the results more accurate and reliable.

The above descriptions are only preferred embodiments of the present utility model, and are not intended to limit the present utility model. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present utility model shall be included in the Within the protection scope of the present utility model.

Claims (9)

1. A fiber optic passive wind speed measurement device, characterized in that it comprises a fixed chassis, a wind cup structure and a fiber grating strain sensor; the fixed chassis is provided with a central shaft that can rotate relative to the fixed chassis, and the center The rotating shaft is connected with the wind cup structure and the rotating disk, and the rotating disk is provided with a magnet; the fiber grating strain sensor is arranged on the cantilever of the cantilever beam, and the free end of the cantilever beam is provided with The magnets of the rotating disk are opposite the magnets in the axial direction. 2 . The fiber optic passive wind speed measuring device according to claim 1 , wherein the central rotating shaft is arranged on the fixed chassis through a bearing fixing device. 3 . 3. The optical fiber passive wind speed measuring device according to claim 2, wherein the central rotating shaft runs through the fixed chassis and the bearing fixing device, and one end of the central rotating shaft is connected to the wind cup structure , the other end of the central rotating shaft is fixed on the central area of the rotating disc. 4. The optical fiber passive wind speed measuring device according to any one of claims 1-3, characterized in that the cantilever beam is arranged on the fixed chassis. 5. The fiber optic passive wind speed measuring device according to any one of claims 1-3, characterized in that the fiber grating strain sensor is welded on the cantilever beam. 6. The optical fiber passive wind speed measurement device according to any one of claims 1-3, wherein the wind cup structure is a three-cup wind cup structure. 7. The optical fiber passive wind speed measurement device according to any one of claims 1-3, characterized in that, the wind cup of the wind cup structure is a semicircular type. 8. The optical fiber passive wind speed measuring device according to any one of claims 1-3, characterized in that the material of the wind cup structure is aluminum. 9. The optical fiber passive anemometer device according to any one of claims 1-3, characterized in that the material of the rotating disk is aluminum.