CN111398627A - Flow velocity sensor and system based on optical fiber structure - Google Patents
Flow velocity sensor and system based on optical fiber structure Download PDFInfo
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- CN111398627A CN111398627A CN202010287204.3A CN202010287204A CN111398627A CN 111398627 A CN111398627 A CN 111398627A CN 202010287204 A CN202010287204 A CN 202010287204A CN 111398627 A CN111398627 A CN 111398627A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
- G01P5/00—Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft
- G01P5/26—Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft by measuring the direct influence of the streaming fluid on the properties of a detecting optical wave
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Abstract
The invention relates to a flow velocity sensor and a system based on an optical fiber structure, in particular to the field of flow velocity detection devices. The flow rate sensor includes: the device comprises a blocking plate, a metal pipe, a fixing plate, an optical fiber and a water through hole; the tubular metal resonator sets up to conical heliciform structure, the less one end fixed connection of tubular metal resonator radius is on the barrier plate, the other end is connected with the barrier plate, optic fibre sets up inside the tubular metal resonator, and the tubular metal resonator both ends are connected with fixed plate and barrier plate respectively, fixed plate central point puts and is provided with the water hole, the radius of crossing the water hole equals with the radius of the tubular metal resonator that is close to barrier plate one end, when measuring the flow rate, the material that awaits measuring gets into heliciform optic fibre from the water hole of crossing of fixed plate, through the impact to barrier plate and optic fibre, make conical heliciform structure's tubular metal resonator take place deformation, and then make the inside optic fibre of this tubular metal resonator also take place deformation, optic fibre can produce bending loss this moment, through the change of.
Description
Technical Field
The invention relates to the field of flow velocity detection devices, in particular to a flow velocity sensor and a system based on an optical fiber structure.
Background
In daily life, scientific research and industrial production, flow rate is a very important physical factor, and generally, flow rate refers to the distance traveled by a particle of a gas or liquid flow in a unit of time. The flow velocity of each point of the water flow in the channel and the river channel is different, the flow velocity near the bottom and the edge of the river (channel) is small, the flow velocity near the water surface in the center of the river is maximum, and the average flow velocity of the cross section is usually used for representing the velocity of the water flow of the cross section for simple calculation.
In the prior art, the measurement of the flow velocity generally includes ultrasonic measurement, electromagnetic wave measurement, and acousto-optic measurement, wherein the ultrasonic measurement is performed by using an ultrasonic flow velocity sensing measuring instrument to measure the flow velocity in a non-contact measurement manner, the electromagnetic wave measurement is performed by using an electromagnetic wave flow velocity sensing measuring instrument to measure the flow velocity, and the acousto-optic measurement is performed by using an acoustic doppler flow velocity sensing measuring instrument to measure the flow velocity.
However, the above device has a complicated structure, a large volume, and is susceptible to environmental influences, so that the measurement of the flow rate is inaccurate.
Disclosure of Invention
The present invention aims to provide a flow velocity sensor and a flow velocity measurement system based on an optical fiber structure, which are used for solving the problems of the prior art that the device has a complicated structure, a large volume, and is easily affected by the environment, so that the flow velocity measurement is inaccurate.
In order to achieve the above purpose, the embodiment of the present invention adopts the following technical solutions:
in a first aspect, the present application provides a flow velocity sensor based on an optical fiber structure, the flow velocity sensor comprising: the device comprises a blocking plate, a metal pipe, a fixing plate, an optical fiber and a water through hole; the tubular metal resonator sets up to conical heliciform structure, and the less one end fixed connection of tubular metal resonator radius is on the barrier plate, and the other end is connected with the fixed plate, and optic fibre setting is inside the tubular metal resonator, and the tubular metal resonator both ends are connected with fixed plate and barrier plate respectively, and fixed plate central point puts and is provided with the water hole, and the radius of crossing the water hole equals with the radius of the tubular metal resonator that is close to barrier plate one end.
Optionally, the thread pitch of the metal tube is 80mm to 100mm, the spiral radius of one end of the metal tube close to the fixing plate is 280mm to 300mm, and the spiral radius of one end of the metal tube close to the blocking plate is 50mm to 70 mm.
Optionally, the metal tube is made of a corrosion-resistant alloy.
Optionally, the fixing plate is square in shape.
Optionally, the side length of the fixing plate is 600 mm-700 mm.
Optionally, the radius of the circular hole in the middle of the fixing plate is 200 mm-300 mm.
Optionally, the blocking plate is circular in shape.
Optionally, the radius of the blocking plate is 50 mm-70 mm.
Optionally, the flow rate sensor further comprises a flow rate increasing structure, wherein the flow rate increasing structure is a plurality of rectangular sheets, and the plurality of rectangular sheets are arranged on the metal pipe.
In a second aspect, the present application further provides a flow rate sensing system based on an optical fiber structure, the flow rate sensing system including: a laser, a detector and the flow sensor of any one of the first aspect, the laser and the detector being arranged at respective ends of an optical fiber of the flow sensor.
The invention has the beneficial effects that:
the invention provides a flow velocity sensor based on an optical fiber structure, which comprises: the device comprises a blocking plate, a metal pipe, a fixing plate, an optical fiber and a water through hole; the tubular metal resonator sets up to conical heliciform structure, the less one end fixed connection of tubular metal resonator radius is on the barrier plate, the other end is connected with the barrier plate, optic fibre sets up inside the tubular metal resonator, and the tubular metal resonator both ends are connected with fixed plate and barrier plate respectively, fixed plate central point puts and is provided with the water hole, the radius of crossing the water hole equals with the radius of the tubular metal resonator that is close to barrier plate one end, when measuring the flow rate, the material that awaits measuring gets into heliciform optic fibre from the water hole of crossing of fixed plate, through the impact to barrier plate and optic fibre, make conical heliciform structure's tubular metal resonator take place deformation, and then make the inside optic fibre of this tubular metal resonator also take place deformation, optic fibre can produce bending loss this moment, through the change of.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.
Fig. 1 is a schematic structural diagram of a flow velocity sensor based on an optical fiber structure according to an embodiment of the present invention;
FIG. 2 is a schematic cross-sectional view of a metal tube according to an embodiment of the invention;
fig. 3 is a schematic plan view of a spiral metal tube of an optical fiber flow rate sensor according to an embodiment of the present invention;
fig. 4 is a schematic plan view of a spiral metal tube of another optical fiber flow rate sensor according to an embodiment of the present invention;
fig. 5 is a schematic cross-sectional view of a rectangular metal tube according to an embodiment of the present invention.
Icon: 10-a barrier plate; 20-a metal tube; 30-fixing the plate; 40-water through hole, 50-optical fiber; 60-flow rate increasing structure.
Detailed Description
In order to make the objects, 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 drawings in the embodiments of the present invention, and it is obvious that the described embodiment is a metal plate embodiment of the present invention, and not all embodiments. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.
Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.
In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings or the orientations or positional relationships that the products of the present invention are conventionally placed in use, and are only used for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used solely to distinguish one from another and are not to be construed as indicating or implying relative importance.
Furthermore, the terms "horizontal", "vertical" and the like do not imply that the components are required to be absolutely horizontal or pendant, but rather may be slightly inclined. For example, "horizontal" merely means that the direction is more horizontal than "vertical" and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.
In the description of the present invention, it should also be noted that, unless otherwise explicitly specified or limited, the terms "disposed," "mounted," "connected," and "connected" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
In order to make the implementation of the present invention clearer, the following detailed description is made with reference to the accompanying drawings.
Fig. 1 is a schematic structural diagram of a flow velocity sensor based on an optical fiber structure according to an embodiment of the present invention; as shown in fig. 1, the present application provides a flow rate sensor based on an optical fiber structure, the flow rate sensor including: the optical fiber fixing device comprises a blocking plate 10, a metal pipe 20, a fixing plate 30, an optical fiber 50 and a water through hole 40; the tubular metal resonator 20 sets up to conical helical structure, and the less one end fixed connection of tubular metal resonator 20 radius is on the baffle 10, and the other end is connected with fixed plate 30, and optic fibre 50 sets up inside tubular metal resonator 20, and tubular metal resonator 20 both ends also are connected with fixed plate 30 and baffle 10 respectively, and fixed plate 30 central point puts and is provided with water hole 40, and the radius of crossing water hole 40 equals with the radius of tubular metal resonator 20 that is close to baffle 10 one end.
Fig. 2 is a schematic plan view of a spiral metal tube of an optical fiber flow rate sensor according to an embodiment of the present invention; FIG. 3 is a schematic cross-sectional view of a metal tube according to an embodiment of the invention, as shown in FIGS. 2 and 3; in fig. 1, the flow velocity sensor includes a blocking plate 10, a metal tube 20, a fixing plate 30, a water through hole 40, and an optical fiber 50, referring to fig. 2, the metal tube 20 is configured as a conical spiral structure, and correspondingly, the optical fiber 50 inside the metal tube 20 is also configured as a conical spiral structure, generally, the optical fiber 50 is fixed inside the metal tube 20 by using a heat insulating glue, referring to fig. 3, one end of the metal tube 20 with a larger spiral radius is connected to the fixing plate 30, one side with a smaller spiral radius is connected to the blocking plate 10, the water through hole 40 is disposed at the center of the fixing plate 30, when measuring the flow velocity, the water flow enters the center of the metal tube 20 from the water through hole 40 in the middle of the fixing plate 30 and acts on the metal tube 20 and the blocking plate 10, the blocking plate 10 and the metal tube 20 are deformed by impact, and the optical fiber 20 is deformed, when the optical fiber 20 is deformed and bent, mode or mode average power coupling is generated, and a part of the core guided mode is converted into a cladding leakage mode, so that the optical fiber 20 generates bending loss, and the change of the water flow velocity can be measured according to the bending loss generated by the optical fiber 50. In addition, the optical fiber 50 is fixed inside the metal tube 10, firstly, the metal tube 10 can effectively protect the optical fiber 50 from being influenced by external factors, so that the service life can be prolonged, secondly, because the optical fiber is soft in texture, the metal tube 10 plays a supporting role for the optical fiber 50, metal has strong elastic deformation capacity, so that the measurement precision cannot be reduced due to excessive use times, and it needs to be noted that the optical fiber 50 is fixed by using heat-insulating glue, so that the influence of external temperature on the measurement precision of the flow velocity sensor is reduced; the flow velocity sensor provided by the invention has the advantage of accurate measurement result because the optical measurement has the advantages of high sensitivity and the like. In application, light is coupled into the optical fiber 50, and the propagation characteristics thereof are not affected by the external environment, so that the flow velocity sensor based on the present principle has an advantage of wide application range.
Optionally, the metal tube 10 may be provided with one or more optical fibers 50, which are selected according to actual needs and are not specifically limited herein, and if the optical fibers 50 are formed by a plurality of optical fibers, the optical fibers 50 may also be fixed together by a heat insulation adhesive.
Optionally, the thread pitch of the metal tube is 80mm to 100mm, the spiral radius of one end of the metal tube close to the fixing plate is 280mm to 300mm, and the spiral radius of one end of the metal tube close to the blocking plate is 50mm to 70 mm.
The pitch of the metal pipe is 80 mm-100 mm, and the pitch of the spiral metal pipe can be 80mm, 90mm or 100 mm; the radius of the spiral starting end of the spiral metal pipe is 280mm to 300mm, and the radius of the spiral starting end of the spiral metal pipe can be 280mm, 290mm or 300 mm; the radius of the spiral tail end of the spiral metal pipe is 50 mm-70 mm, and the radius of the spiral tail end of the spiral metal pipe can be 50mm, 60mm or 70 mm.
Alternatively, the metal tube 20 is made of a corrosion-resistant alloy.
The alloy can be metal with elastic deformation, and the metal is plated with an antirust and corrosion-resistant antirust film.
Alternatively, the fixing plate 30 is square in shape.
Optionally, the length of the fixed plate is any length between 650mm and 700mm, the fixed plate may be a square structure that becomes 650mm, and may also be a square structure that has a length of 700mm, and the length of the fixed plate is selected according to actual conditions, and is not specifically limited herein.
Optionally, the radius of the water through hole 40 in the middle of the fixing plate 30 is any length between 200mm and 300 mm.
The radius of the water through hole 40 in the middle of the fixing plate 30 is any size of 200 mm-300 mm, and is selected according to the actual situation, and is not limited specifically here.
Alternatively, the blocking plate 10 is circular in shape.
Optionally, the radius of the blocking plate 10 is 50mm to 70 mm.
The radius of the blocking plate 10 is 50mm to 70mm, the radius of the blocking plate 10 may be 50mm, 60mm or 70mm, and the radius of the blocking plate 10 is selected according to actual conditions, which is not specifically limited herein.
FIG. 4 is a schematic structural diagram of another flow velocity sensor based on an optical fiber structure according to an embodiment of the present invention; as shown in fig. 4, the flow rate sensor may further include a flow rate increasing structure 60, where the flow rate increasing structure 60 is a plurality of rectangular pieces, and the plurality of rectangular pieces are disposed on the metal pipe.
Be provided with velocity of flow increase structure 60 at this tubular metal resonator 20, this velocity of flow increase structure 60 is a plurality of rectangle pieces, a plurality of rectangle pieces set up on this tubular metal resonator 20, increase spiral tubular metal resonator 20 to with the area of contact of rivers, when rivers pass through the sensor, this rectangular pipe 20 is because the increase of lifting surface area, spiral tubular metal resonator 20 is more big under the rivers of equal velocity of flow degree of deformation degree, consequently, the bending degree grow of optic fibre 50, the bending loss grow of production, thereby increase the perception sensitivity of this sensor to velocity of flow, the measurement accuracy and the sensitivity of this sensor have been improved.
Optionally, the plurality of rectangular pieces may be discontinuous small pieces or continuous periodic rectangular strips, which is not specifically limited herein, and the rectangular pieces may be made of a material with small elastic deformation and high rigidity.
Optionally, the rectangular sheet has a length of 8 mm-10 mm and a width of 3 mm-5 mm, and if the rectangular sheet is a continuous rectangular strip, the width is also 3 mm-5 mm,
fig. 5 is a schematic structural diagram of a flow velocity sensor based on an optical fiber structure according to an embodiment of the present invention; as shown in fig. 5, the metal tube 20 may be a metal tube 20 with a rectangular cross section, and the number of the optical fibers 50 in the metal tube 20 is two.
This tubular metal resonator 20's cross section is the rectangle, rectangular tubular metal resonator 20 is compared in circular tubular metal resonator 20, the area of stress to rivers has been increased, make the sensor improve to the perception sensitivity of velocity of water, two optic fibre 50 have made things convenient for simultaneously again fixed in tubular metal resonator 20, two optic fibre 50 in this tubular metal resonator 20 are not divided two, but a complete optic fibre is worn into from the big one side of spiral tubular metal resonator spiral radius, wear back again to the spiral end, when light propagated in optic fibre like this, the bending loss that two optic fibres of same position department all can produce, thereby make the precision of this sensor increase. In addition, the design enables the incident port and the exit port of the optical fiber to be arranged at one end close to the fixing plate 30, and in the flow velocity sensing system based on the optical fiber structure, the system comprises the laser of the incident port and the detector of the exit port which can be packaged together, thereby simplifying the structure of the system.
The invention provides a flow velocity sensor based on an optical fiber structure, which comprises a baffle plate 10, a metal tube 20, a fixing plate 30, a water through hole 40 and an optical fiber 50, wherein the metal tube 20 is arranged in a spiral shape, the optical fiber 50 is fixed inside the metal tube 20 by using heat insulation glue, one side with a large spiral radius of the spiral metal tube 20 is connected to the fixing plate 30, the other side with a small spiral radius is connected with the baffle plate 10, the water through hole 40 is arranged in the middle of the fixing plate 30, when the flow velocity is measured, water flow enters the center of the spiral metal tube 20 from the water through hole 40 in the middle of the fixing plate 30, the spiral optical fiber 20 is lengthened to generate micro bending by impacting the baffle plate 10 and the metal tube 20, when the optical fiber 20 is bent, the mode or the coupling of the mode average power is generated, so that a part of a fiber core guide mode is converted into a cladding leakage, the change in the flow rate of the water can be measured from the bending loss generated by the optical fiber 50.
The application also provides a velocity of flow sensing system based on optic fibre structure, and the velocity of flow sensing system includes: a laser, a detector and the flow sensor of any one of the first to fourth aspects, the laser and the detector being connected to an entrance port and an exit port of the optical fiber 50, respectively.
The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes will occur to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. A flow rate sensor based on an optical fiber structure, the flow rate sensor comprising: the device comprises a blocking plate, a metal pipe, a fixing plate, an optical fiber and a water through hole; the utility model discloses a stop plate, including metal pipe, baffle plate, optical fiber, fixed plate central point, the metal pipe sets up to conical heliciform structure, the less one end fixed connection of metal pipe radius is in on the baffle plate, the other end with the fixed plate is connected, optic fibre sets up inside the metal pipe, just the metal pipe both ends respectively with the fixed plate with the baffle plate is connected, fixed plate central point puts and is provided with cross the water hole, cross the radius in water hole and be close to baffle plate one end the radius of metal pipe equals.
2. The optical fiber structure-based flow rate sensor according to claim 1, wherein the metal tube has a pitch of 80mm to 100mm, a spiral radius of 280mm to 300mm at an end of the metal tube adjacent to the fixing plate, and a spiral radius of 50mm to 70mm at an end of the metal tube adjacent to the blocking plate.
3. The optical fiber structure-based flow rate sensor according to claim 1, wherein the metal tube is made of a corrosion-resistant alloy.
4. The optical fiber structure-based flow velocity sensor according to claim 1, wherein the fixing plate has a square shape.
5. The optical fiber structure-based flow rate sensor according to claim 4, wherein the side length of the fixing plate is 600mm to 700 mm.
6. The optical fiber structure-based flow rate sensor according to claim 1, wherein the central circular hole of the fixing plate has a radius of 200mm to 300 mm.
7. The optical fiber structure-based flow rate sensor according to claim 1, wherein the blocking plate has a circular shape.
8. The optical fiber structure-based flow rate sensor according to claim 6, wherein the blocking plate has a radius of 50mm to 70 mm.
9. The optical fiber structure-based flow rate sensor according to claim 5, further comprising a flow rate increasing structure, wherein the flow rate increasing structure is a plurality of rectangular pieces, and the plurality of rectangular pieces are disposed on the metal pipe.
10. A flow rate sensing system based on an optical fiber structure, the flow rate sensing system comprising: a laser, a detector and a flow sensor according to any one of claims 1 to 9, said laser and said detector being respectively disposed at both ends of said optical fiber of said flow sensor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010287204.3A CN111398627A (en) | 2020-04-13 | 2020-04-13 | Flow velocity sensor and system based on optical fiber structure |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010287204.3A CN111398627A (en) | 2020-04-13 | 2020-04-13 | Flow velocity sensor and system based on optical fiber structure |
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| CN111398627A true CN111398627A (en) | 2020-07-10 |
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| CN202010287204.3A Withdrawn CN111398627A (en) | 2020-04-13 | 2020-04-13 | Flow velocity sensor and system based on optical fiber structure |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112212966A (en) * | 2020-11-05 | 2021-01-12 | 中国计量大学 | Optical fiber vibration sensor based on femtosecond laser writing spiral waveguide |
-
2020
- 2020-04-13 CN CN202010287204.3A patent/CN111398627A/en not_active Withdrawn
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112212966A (en) * | 2020-11-05 | 2021-01-12 | 中国计量大学 | Optical fiber vibration sensor based on femtosecond laser writing spiral waveguide |
| CN112212966B (en) * | 2020-11-05 | 2022-09-13 | 中国计量大学 | Optical fiber vibration sensor based on femtosecond laser writing spiral waveguide |
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Application publication date: 20200710 |
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