阅读说明：本技术 一种光纤光栅靶式流量计 (Fiber grating target type flowmeter ) 是由 孙世政 向洋 张虹光 何泽银 于 2019-11-16 设计创作，主要内容包括：本发明涉及流量检测领域,具体公开了一种光纤光栅靶式流量计,包括三通管、靶盘、悬臂梁、端盖、传导光纤及光纤光栅,所述三通管呈“⊥”形且其下端两侧管口用于与待测管道连通、上端部管口用于与端盖密封连接,所述悬臂梁的上端连接于端盖、下端连接于靶盘,所述传导光纤的一端与光纤光栅连接、另一端从靶盘穿出并用于与外部解调设备相连；设置两根所述光纤光栅及两根对应的所述传导光纤,其中一所述光纤光栅连接在悬臂梁上、另一所述光纤光栅连接在靶盘后部。本发明可有效提高测量精度,同时还能实现流量与温度的同时检测。(The invention relates to the field of flow detection, and particularly discloses a fiber grating target type flowmeter, which comprises a three-way pipe, a target disc, a cantilever beam, an end cover, a conducting optical fiber and a fiber grating, wherein the three-way pipe is in an ⊥ shape, pipe orifices on two sides of the lower end of the three-way pipe are used for being communicated with a pipeline to be detected, pipe orifices on the upper end of the three-way pipe are used for being hermetically connected with the end cover, the upper end of the cantilever beam is connected with the end cover, the lower end of the cantilever beam is connected with the target disc, one end of the conducting optical fiber is connected with the fiber grating, the other end of the conducting optical fiber penetrates out of the target disc and is used for being connected with external demodulation equipment, the two fiber gratings and the two corresponding conducting optical fibers are arranged, one of the fiber grating is.)

1. A fiber grating target type flowmeter comprises a three-way pipe, a target disc, cantilever beams, end covers, conducting fibers and fiber gratings, wherein the three-way pipe is in a shape of ⊥, pipe orifices on two sides of the lower end of the three-way pipe are used for being communicated with a pipeline to be measured, pipe orifices on the upper end of the three-way pipe are used for being in sealing connection with the end covers, the upper end of each cantilever beam is connected to the end covers, the lower end of each cantilever beam is connected to the target disc, one end of each conducting fiber is connected with the fiber gratings, the other end of each conducting fiber penetrates out of the target disc and is used for being connected with external demodulation equipment, the fiber grating target type flowmeter is characterized in that the two fiber gratings and the.

2. The fiber grating target flowmeter of claim 1, wherein: and the two fiber gratings are connected to the cantilever beam and the target disc in an adhesion mode.

3. The fiber grating target flowmeter of claim 1, wherein: the target disc, the cantilever beam and the end cover are integrally processed into an integrated target, and a through hole for the conduction optical fiber to pass through is formed in the center of the integrated target.

4. The fiber grating target flowmeter of claim 3, wherein: the target disc and the cantilever beam are both of cylindrical structures, and the axis of the target disc is perpendicular to the axis of the cantilever beam.

5. The fiber grating target flowmeter of claim 1, wherein: the target diameter ratio of the diameter of the target disc to the pipe diameter of the three-way pipe is 0.5, and the axis of the target disc is coaxial with the axes of the pipe orifices on the two sides of the lower end of the three-way pipe.

6. The fiber grating target flowmeter of any one of claims 1-5, wherein: the three pipe orifices of the three-way pipe are respectively provided with a flange, and the end cover is provided with a connecting hole which is matched and connected with the flange at the pipe orifice at the upper end part of the three-way pipe.

7. The fiber grating target flowmeter of any one of claims 1-5, wherein: the fiber grating connected to the cantilever beam is positioned in the middle of the cantilever beam.

Technical Field

The invention relates to the field of flow detection, in particular to a fiber bragg grating target type flowmeter.

Background

With the development of science and technology since the modern society is stepped on, the flow measurement plays a very important role in the fields of petroleum, chemical engineering, biomedicine, energy metering and environmental monitoring. At present, the target type flowmeter mostly generates pressure on a target disc when fluid flows through the target disc, so that a cantilever beam connected with the target disc deforms, strain is measured through an electric strain sensor and converted into an electric signal to be output, and finally flow data are obtained. However, the sensor is an electric sensor which is easily interfered by an external electromagnetic field, and the requirement on the measuring environment is high, so that the application range of the sensor is limited, and the electronic elements on the sensor are easily corroded by fluid, so that the measuring accuracy of the sensor is influenced.

The fiber bragg grating is a novel optical passive device appearing in recent years, wherein the fiber bragg grating is extremely sensitive to temperature and stress, changes of external temperature and stress are reflected by detecting changes of central wavelength of the fiber bragg grating, physical quantities such as temperature, stress and deformation can be effectively monitored, and the fiber bragg grating has a wide application prospect due to the advantages of good flexibility, strong electromagnetic interference resistance, high sensitivity, small size and the like.

The design principle of the fiber grating target flowmeter is that the wavelength change of the fiber grating under the action of tension is in a linear relation with the tension. The water flow detection is one of the most basic measurement items in the measurement technology, and a fiber grating target flowmeter accurately measures the flow velocity by utilizing the advantages of a fiber grating. For example, patent CN 108548572 a discloses a fiber grating target flowmeter, in which a fluid flowing through the flowmeter generates a force effect on a load-bearing plate, and then the force effect is transmitted to a connecting rod via a lever composed of a contact rod and a transmission rod, a cantilever connected to the contact rod is bent, the bottom tension of the cantilever is the largest, and a grating adhered to the bottom of the cantilever generates a corresponding wavelength shift. However, the fiber grating target flowmeter with the structure has low measurement accuracy under the influence of temperature, and cannot detect the temperature of the fluid.

Therefore, in order to solve the above problems, a fiber grating target flowmeter is needed, which effectively improves the measurement accuracy and simultaneously can realize the simultaneous detection of the flow and the temperature.

Disclosure of Invention

In view of this, the present invention provides a fiber grating target flowmeter, which effectively improves the measurement accuracy and simultaneously can detect the flow rate and the temperature.

The invention provides a fiber grating target type flowmeter which comprises a three-way pipe, a target disc, a cantilever beam, an end cover, conducting fibers and fiber gratings, wherein the three-way pipe is in an ⊥ shape, pipe orifices on two sides of the lower end of the three-way pipe are used for being communicated with a pipeline to be measured, pipe orifices on the upper end of the three-way pipe are used for being hermetically connected with the end cover, the upper end of the cantilever beam is connected to the end cover, the lower end of the cantilever beam is connected to the target disc, one end of each conducting fiber is connected with the fiber gratings, the other end of each conducting fiber penetrates out of the target disc and is used for being connected with external demodulation equipment, the two fiber gratings and the two corresponding conducting fibers are arranged.

As a preferred technical scheme, the two fiber gratings are connected to the cantilever beam and the target disc in an adhesion mode.

As a preferred technical scheme, the target disc, the cantilever beam and the end cover are integrally processed into an integrated target, and the center of the integrated target is provided with a through hole for a conduction optical fiber to pass through.

As a preferred technical scheme, the target disc and the cantilever beam are both of cylindrical structures, and the axis of the target disc is perpendicular to the axis of the cantilever beam.

As a preferred technical scheme, the target diameter ratio of the diameter of the target disc to the pipe diameter of the three-way pipe is 0.5, and the axis of the target disc is coaxial with the axes of pipe orifices at two sides of the lower end of the three-way pipe.

As a preferred technical scheme, three pipe orifices of the three-way pipe are respectively provided with a flange, and the end cover is provided with a connecting hole which is in matched connection with the flange at the pipe orifice at the upper end part of the three-way pipe.

As a preferred technical scheme, the fiber grating connected to the cantilever beam is positioned in the middle of the cantilever beam.

Compared with the prior art, the fiber bragg grating target type flowmeter has the following beneficial technical effects:

firstly, one of the two fiber gratings is arranged on the cantilever beam, and when the cantilever beam generates yield deformation and temperature change, the central wavelength of the fiber grating is changed; the other is arranged at the rear part of the target disc, and because the target disc cannot generate yield deformation, the central wavelength of the fiber grating is only influenced by temperature change; the two fiber gratings are connected with external demodulation equipment through conducting fibers, and the flow and temperature information of the pipeline fluid can be obtained through calculation and analysis by adopting a reference grating method, so that the measurement precision is effectively improved, and the simultaneous detection of the flow and the temperature is realized;

secondly, the end cover, the cylindrical cantilever beam and the target disc are integrally processed, and the manufactured integrated target can effectively reduce movable parts of the flowmeter, improve the structural stability of the flowmeter and further improve the measurement precision;

thirdly, the cantilever beam with the hollow cylindrical structure can effectively reduce the pressure loss of the fluid and further improve the measurement precision;

fourthly, each pipe orifice of the three-way pipe is provided with a flange, so that the three-way pipe is convenient to mount and dismount with a pipeline to be measured and an end cover, and the convenience of the use of the flowmeter is improved.

Drawings

FIG. 1 is a schematic front sectional view of the present invention;

FIG. 2 is a schematic side view of the present invention;

FIG. 3 is a schematic cross-sectional front view of a tee of the present invention;

FIG. 4 is a schematic top view of a tee of the present invention;

FIG. 5 is a schematic front cross-sectional view of an integral target of the present invention;

FIG. 6 is a schematic side view of an integrated target of the present invention.

In the figure: 1-a three-way pipe; 2-target disc; 3-cantilever beam; 4-end cover; 5-a conducting optical fiber; 6-fiber grating.

Detailed Description

The technical scheme in the embodiment of the invention will be clearly and completely described below with reference to the accompanying drawings; it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments, and all other embodiments obtained by those skilled in the art without any inventive work are within the scope of the present invention.

As shown in fig. 1 to 6, in the present embodiment, a fiber grating target flowmeter is provided, which includes a three-way pipe 1, a target disc 2, a cantilever beam 3, an end cap 4, a conducting fiber 5 and a fiber grating 6, where the three-way pipe 1 is "⊥" shaped, and its two side orifices at the lower end are used for communicating with a pipe to be measured, and its upper end orifice is used for being hermetically connected with the end cap 4, the upper end of the cantilever beam 3 is connected to the end cap 4, and its lower end is connected to the target disc 2, and one end of the conducting fiber 5 is connected to the fiber grating 6, and its other end penetrates out of the target disc 2 and is.

The three-way pipe 1 has three pipe orifices, wherein the pipe orifices on two sides of the lower end are communicated with a pipeline to be measured, the pipe orifice on the upper end is hermetically connected with the end cover 4 (the upper and lower ends are based on the figure 1), the pipe orifices on two sides of the lower end are coaxially arranged, and the axis of the pipe orifice on the upper end is vertical to the axis of the pipe orifices on two sides of the lower end. When fluid impacts the target disk 2, the target disk 2 is stressed and the cantilever beam 3 generates yield deformation. The fiber grating 6-target flowmeter has the advantages of electromagnetic interference resistance, corrosion resistance, high measurement precision, simple structure, safety and reliability, and the basic measurement principle is consistent with that of the prior art and is not repeated herein.

The fiber grating target flowmeter provided by the embodiment is mainly improved in that the flowmeter is provided with two fiber gratings 6 and two corresponding conducting fibers 5, wherein one fiber grating 6 is connected to the cantilever beam 3, and the other fiber grating 6 is connected to the rear part of the target disc 2. The two conducting optical fibers 5 correspond to the two fiber gratings 6 one by one, and the independent measurement of the two fiber gratings 6 is realized. The rear of the target disk 2 refers to a side of the target disk 2 facing away from the direction of fluid flow. Both fiber gratings 6 are preferably connected to the cantilever 3 and the target plate 2 by conventional bonding means, such as epoxy bonding. Preferably, the fiber grating 6 connected to the cantilever beam 3 is located in the middle of the cantilever beam 3, and the center of the fiber grating 6 coincides with the center of the cantilever beam 3.

When fluid flows through the three-way pipe 1 to impact the target disc 2, the target disc 2 is stressed and is transmitted to the cantilever beam 3, so that the cantilever beam 3 generates yield deformation, and the central wavelength of the fiber grating 6 stuck on the cantilever beam 3 is influenced by strain and temperature to generate drift; because the cylindrical target disk 2 can not generate yield deformation, the central wavelength of the fiber bragg grating 6 stuck on the cylindrical target disk is only influenced by temperature change, the two fiber bragg gratings 6 are connected with external demodulation equipment through the conducting optical fiber 5, the flow and temperature information of the pipeline fluid is obtained through calculation and analysis, the cross sensitivity problem is solved and the simultaneous detection of the flow and the temperature is realized by adopting a reference grating method.

In this embodiment, the target disc 2, the cantilever beam 3 and the end cap 4 are integrally processed into an integrated target, and a through hole for passing the conducting optical fiber 5 is formed in the center of the integrated target; the conducting optical fiber 5 is led out from the through hole; of course, the through-hole needs to form a sealing structure after the guiding optical fiber 5 is led out; the end cover 4, the cylindrical cantilever beam 3 and the target disc 2 are integrally processed, and the manufactured integrated target can effectively reduce movable parts of the flowmeter, so that the structural stability of the flowmeter is improved, and the measurement precision is further improved.

In this embodiment, the target disk 2 and the cantilever beam 3 are both cylindrical structures, and the axis of the target disk 2 is perpendicular to the axis of the cantilever beam 3; the axis of the target disc 2 is parallel to the axes of the pipe orifices at the two sides of the lower end of the three-way pipe 1, and the axis of the cantilever beam 3 is superposed with the axis of the pipe orifice at the upper end part of the three-way pipe 1; the structure can effectively reduce the pressure loss of the fluid and further improve the measurement precision.

In the embodiment, the target diameter ratio of the diameter of the target disc 2 to the pipe diameter of the three-way pipe 1 is 0.5, and the axis of the target disc 2 is coaxial with the axes of pipe orifices at two sides of the lower end of the three-way pipe 1; the target disc 2 is a disc structure, and the diameter of the target disc is 1/2 the pipe diameter of the three-way pipe 1; with this structure, the pressure loss of the fluid can be reduced, and the measurement accuracy can be further improved.

In this embodiment, three pipe orifices of the three-way pipe 1 are provided with flanges, and the end cover 4 is provided with a connecting hole which is in matched connection with the flange at the pipe orifice at the upper end part of the three-way pipe 1; the flange and the three-way pipe 1 are integrally formed, so that the processing and the manufacturing are convenient, and the connection stability is improved; the flange is convenient to install and detach with the pipeline to be tested and the end cover 4, and the convenience of using the flowmeter is improved.

The foregoing is merely an example of the present invention and common general knowledge of known specific structures and features of the embodiments is not described herein in any greater detail. It should be noted that, for those skilled in the art, without departing from the structure of the present invention, several changes and modifications can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicability of the patent. The scope of the claims of the present application shall be determined by the contents of the claims, and the description of the embodiments and the like in the specification shall be used to explain the contents of the claims.