CN110567537A - gravity rod type optical fiber flow sensor and flow detection method thereof - Google Patents
gravity rod type optical fiber flow sensor and flow detection method thereof Download PDFInfo
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- CN110567537A CN110567537A CN201910851439.8A CN201910851439A CN110567537A CN 110567537 A CN110567537 A CN 110567537A CN 201910851439 A CN201910851439 A CN 201910851439A CN 110567537 A CN110567537 A CN 110567537A
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- 230000005484 gravity Effects 0.000 title claims abstract description 43
- 239000013307 optical fiber Substances 0.000 title claims abstract description 42
- 238000001514 detection method Methods 0.000 title claims abstract description 14
- 239000012530 fluid Substances 0.000 claims abstract description 27
- 238000005096 rolling process Methods 0.000 claims description 12
- 238000000034 method Methods 0.000 claims description 6
- 239000000523 sample Substances 0.000 claims description 6
- 239000004744 fabric Substances 0.000 claims description 4
- 239000000835 fiber Substances 0.000 claims description 3
- 238000007789 sealing Methods 0.000 claims description 3
- 230000008878 coupling Effects 0.000 claims description 2
- 238000010168 coupling process Methods 0.000 claims description 2
- 238000005859 coupling reaction Methods 0.000 claims description 2
- 238000005259 measurement Methods 0.000 abstract description 6
- 238000004364 calculation method Methods 0.000 abstract description 2
- 238000006243 chemical reaction Methods 0.000 abstract description 2
- 238000013461 design Methods 0.000 abstract description 2
- 238000012545 processing Methods 0.000 abstract description 2
- 230000001737 promoting effect Effects 0.000 abstract description 2
- 230000035945 sensitivity Effects 0.000 abstract description 2
- 230000008569 process Effects 0.000 description 4
- 238000011161 development Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000005265 energy consumption Methods 0.000 description 2
- 230000009471 action Effects 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 238000011835 investigation Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000004806 packaging method and process Methods 0.000 description 1
Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
- G01F1/05—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects
- G01F1/20—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects by detection of dynamic effects of the flow
- G01F1/28—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects by detection of dynamic effects of the flow by drag-force, e.g. vane type or impact flowmeter
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- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- General Physics & Mathematics (AREA)
- Measuring Volume Flow (AREA)
Abstract
the invention provides a gravity rod type optical fiber flow sensor and a flow detection method thereof, the sensor has smaller structure, higher accuracy and reliability, better adaptability and interchangeability and the like, the sensor can be suitable for a plurality of fluid flow detection occasions, the pendulum rod structure and the photoelectric sensing principle are combined to be applied to the flow detection field, the output value of an output signal is multiplied after photoelectric conversion and signal processing calculation, the detection sensitivity can be obviously improved for the traditional dynamic measurement mode, the sensor has very important practical application value, and the sensor plays a great promoting role in the design and popularization of a novel flow sensor. Belonging to the field of flow detection.
Description
Technical Field
The invention relates to a gravity rod type optical fiber flow sensor and a detection method thereof, belonging to the field of flow detection.
Background
in modern industrial processes, especially automated processes, various sensors are often used to monitor and control various parameters of the process, to operate the equipment in a normal or optimal state, and to maximize the quality of the product. Sensors have also long penetrated extremely widespread fields such as industrial production, space development, marine exploration, environmental protection, resource investigation, medical diagnostics, biotechnology, and even cultural relic protection. The present invention is one of many classes of sensors-flow sensors. With the development of sensor technology, various flow sensors have appeared, and the most common ones are of a vane type, a vortex street type, a karman vortex type, a hot wire type, etc. However, sensors such as vane type, vortex street type, karman vortex type, hot wire type and the like mostly adopt the traditional dynamic measurement mode, have the limitations of low measurement precision, large energy consumption and the like, and cannot be well performed in many occasions.
Disclosure of Invention
The invention provides a gravity rod type optical fiber flow sensor, which aims to solve the problems that the conventional flow sensor mostly adopts a traditional dynamic measurement mode, has the limitations of low measurement precision, large energy consumption and the like, and cannot be well competent in many occasions.
In order to solve the problems, the gravity rod type optical fiber flow sensor comprises a sensor probe, a photoelectric converter and a signal processor, wherein the sensor probe comprises a shell and a gravity rod, a swing groove with an opening at the lower end is formed in the shell, the gravity rod comprises a rod part and a gravity plate which are vertically arranged, the rod part is positioned in the swing groove, the upper end of the rod part is hinged with the shell, the lower end of the rod part extends out of the opening at the lower end of the swing groove, the gravity plate is fixed at the lower end of the rod part, the rod part is connected with the opening at the lower end of the swing groove in a sealing way through corrugated waterproof cloth, such as corrugated rubber cloth, so that the opening at the lower end of the swing groove is sealed, the swing of the rod part is not influenced by adopting a deployable corrugated structure, the resistance to the rod part is negligible, the middle section of the rod part is a, an incident optical fiber and a receiving optical fiber which point to each other are respectively arranged on the two opposite sides of the shading plate in the swinging groove, a light source is arranged at the other end of the incident optical fiber and used for coupling incident light, the other end of the receiving optical fiber is connected with a photoelectric converter, and the photoelectric converter is connected with a signal processor.
in the sensor, the light-transmitting holes all fall on the optical fiber path between the incident optical fiber and the receiving optical fiber in the process that the rod part swings around the upper end.
In the sensor, the upper end of the rod part is vertically fixed with a hinged rod which is transversely arranged, and two ends of the hinged rod are rotationally fixed in the swing groove through bearings.
In the sensor, a rolling shaft is transversely fixed on the lower side of the light shielding plate on the rod part, the rolling shaft swings along with the rod part, a roller groove is formed in the swing groove along the swing path of the rolling shaft, rollers are rotatably arranged at two ends of the rolling shaft, and the rollers are slidably arranged in the roller groove.
The invention also provides a gravity rod type optical fiber flow detection method, which is characterized in that a swing groove with an opening at the lower end is arranged in a shell, a rod part vertically arranged is arranged in the swing groove, the upper end of the rod part is hinged with the shell, the lower end of the rod part extends out of the opening at the lower end of the swing groove, a gravity plate is fixed at the lower end of the rod part, the middle section of the rod part is a light screen, a light hole is arranged in the middle of the light screen, incident optical fibers and receiving optical fibers which point to each other are respectively arranged at two opposite sides of the light screen in the swing groove, when the flow of fluid is detected, the device is arranged in the fluid, the gravity plate vertically arranged in an initial state is vertical to the flow direction of the fluid, the fluid impacts the gravity plate to swing, so as to drive the light hole to swing, the output light intensity of the light hole is changed, the swing angle of the rod part is calculated, and then the magnitude of the fluid pressure acting on the gravity plate is calculated, so that the value of the flow velocity can be calculated by a fluid mechanics formula, and further the flow value is calculated.
Compared with the prior art, the sensor has the advantages that the sensor has a smaller structure, higher accuracy and reliability, and better adaptability and interchangeability, can be suitable for a plurality of fluid flow detection occasions, combines the swing rod structure and the photoelectric sensing principle and is applied to the flow detection field, the output value of an output signal is multiplied after photoelectric conversion and signal processing calculation, the detection sensitivity can be obviously improved for the traditional dynamic measurement mode, the sensor has very important practical application value, and the sensor plays a great promoting role in the design and popularization of a novel flow sensor.
Drawings
FIG. 1 is a schematic front view of the present invention;
3 FIG. 3 2 3 is 3 a 3 cross 3- 3 sectional 3 view 3 taken 3 along 3 line 3 A 3- 3 A 3 of 3 FIG. 31 3; 3
Fig. 3 is a schematic view of the gravity bar of fig. 2;
FIG. 4 is a schematic diagram of the variation of the intensity of the receiving fiber of the present invention;
Fig. 5 is a force analysis diagram of the gravity plate.
Detailed Description
To make the objects, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail with reference to the accompanying drawings, and it should be understood that the specific embodiments described herein are only for explaining the present invention and are not intended to limit the present invention.
Examples
referring to fig. 1 to 5, the embodiment provides a gravity rod type optical fiber flow sensor, which includes a sensor probe 1, a photoelectric converter 2 and a signal processor 3, wherein the sensor probe 1 includes a housing 11 and a gravity rod 12, a swing groove 13 with an open lower end is formed in the housing 11, the gravity rod 12 includes a rod portion 121 and a gravity plate 122 which are vertically disposed, the rod portion 121 is located in the swing groove 13, the upper end of the rod portion 121 is hinged to the housing 11, a hinge rod 123 is vertically fixed to the upper end of the rod portion 121, the hinge rod 123 is laterally disposed, and two ends of the hinge rod 123 are rotatably fixed in the swing groove 13 through a bearing 124, the lower end of the rod portion 121 extends out from the lower end opening of the swing groove 13, the gravity plate 122 is fixed to the lower end of the rod portion 121, the rod portion 121 and the lower end opening of the swing groove 13 are hermetically connected through a corrugated waterproof cloth 14, such, therefore, the sealing of the opening at the lower end of the swing groove 13 is realized, an expandable corrugated structure is adopted, the swing of the rod part 121 is not affected (the resistance and the pulling force are ignored), the resistance to the rod part 121 is negligible, the middle section of the rod part 121 is a light screen 1211, a light hole 1212 is formed in the middle of the light screen 1211, an incident optical fiber 15 and a receiving optical fiber 16 which point to each other are respectively arranged on the two opposite sides of the light screen 1211 in the swing groove 13, in the process that the rod part 121 swings around the upper end, all the light holes 1212 fall on an optical fiber path between the incident optical fiber 15 and the receiving optical fiber 16, the other end of the incident optical fiber 15 is arranged at the light source 4 to couple incident light, the other end of the receiving optical fiber 16 is connected with the photoelectric converter 2, and the.
A rolling shaft 125 is transversely fixed on the lower side of the light shielding plate 1211 on the rod part 121, the rolling shaft 125 swings along with the rod part 121, a roller groove 131 is formed in the swing groove 13 along the swing path of the rolling shaft 125, rollers 126 are rotatably arranged at both ends of the rolling shaft 125, and the rollers 126 are slidably arranged in the roller groove 131.
the using method comprises the following steps: when the fluid flow is detected, the device is placed in a fluid, the gravity plate 122 vertically arranged in an initial state is perpendicular to the fluid flow direction, the gravity plate 122 is impacted by the fluid to swing, so that the light shielding plate 1211 and the light transmitting hole 1212 are driven to swing, as shown in fig. 4, after M is a rotation angle θ of the light shielding plate 1211, the height of the light transmitting hole 1212 in the optical fiber path direction is reduced (the width is unchanged), so that the output light intensity through the light transmitting hole 1212 is changed (reduced), the light transmitting hole 1212 is designed to be a square hole, the swing angle of the rod portion 121 can be calculated by detecting the variation of the light intensity, the magnitude of the fluid pressure acting on the gravity plate 122 can be calculated, the flow rate value can be calculated, and the flow rate value can be calculated.
Assuming that the pressure of fluid on a stress plate of the gravity rod is P, the flow velocity of the fluid is v, the density of the fluid is rho, and the stress area of the stress plate is SBThe radius of the stress plate is r, and the stress plate has the following components according to hydrodynamics:
In the formula: k is a proportionality coefficient, SB＝πr2。
And because the fluid flow rate is:
Q＝Av (2)
wherein A is the annular gap channel area formed between the through-flow pipeline through which the fluid flows and the gravity rod stress plate, and if the radius of the through-flow pipeline is R, A is pi (R)2-r2) Then combining the formulas (1) and (2) and arranging the following steps:
And the mass of the gravity swing rod is m, the gravity swing rod rotates by an angle theta under the action of fluid pressure F, and as shown in FIG. 5, the component of the gravity in the normal direction is as follows:
F1＝mg sinθ (4)
at this time, because the stress is balanced, so there are:
F＝F1 (5)
Namely: p, pi r2＝mg sinθ
The rotation angle is therefore:
The effective receiving area of the receiving end face of the receiving optical fiber bundle is as follows:
SJ1＝a(b-m) (7)
In the formula SJ1m is the height of the receiving end face of the receiving optical fiber bundle, b is the height of the receiving end face of the receiving optical fiber bundle, and a is the width of the receiving end face of the receiving optical fiber bundle.
And also
The fiber intensity modulation model of the sensor can be expressed as:
Further, the following can be obtained from the formula (3):
substituting equation (10) into equation (9) includes:
it is obvious from the above (11) sensing model of the sensor that, after the packaging structure and the geometric dimensions of the sensor are determined, the output value M is only related to the flow rate Q of the measured fluid, i.e. the output value of the sensor can better reflect the change of the flow rate of the measured fluid.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.
Claims (5)
1. the utility model provides a gravity rod formula optic fibre flow sensor, includes sensor probe (1), photoelectric converter (2) and signal processor (3), its characterized in that: the sensor probe (1) comprises a shell (11) and a gravity rod (12), a swing groove (13) with an opening at the lower end is formed in the shell (11), the gravity rod (12) comprises a rod part (121) and a gravity plate (122) which are vertically arranged, the rod part (121) is positioned in the swing groove (13), the upper end of the rod part (121) is hinged with the shell (11), the lower end of the rod part (121) extends out of the lower opening of the swing groove (13), the gravity plate (122) is fixed at the lower end of the rod part (121), the rod part (121) is in sealing connection with the lower opening of the swing groove (13) through a corrugated waterproof cloth (14), the middle section of the rod part (121) is a shading plate (1211), a light hole (1212) is formed in the middle part of the shading plate (1211), and incident optical fibers (15) and receiving optical fibers (16) which point to each other are respectively arranged on two opposite sides of the shading plate (1211) in the swing, the other end of the incident optical fiber (15) is provided with a light source (4) for coupling incident light, the other end of the receiving optical fiber (16) is connected with the photoelectric converter (2), and the photoelectric converter (2) is connected with the signal processor (3).
2. The gravity rod optical fiber flow sensor according to claim 1, wherein: during the swinging of the rod part (121) around the upper end, the light-transmitting holes (1212) all fall on the optical fiber path between the incident optical fiber (15) and the receiving optical fiber (16).
3. The gravity rod optical fiber flow sensor according to claim 1, wherein: the upper end of the rod part (121) is vertically fixed with a hinged rod (123), the hinged rod (123) is transversely arranged, and two ends of the hinged rod (123) are rotationally fixed in the swing groove (13) through bearings (124).
4. The gravity rod optical fiber flow sensor according to claim 1, wherein: a rolling shaft (125) is transversely fixed on the lower side of the light shielding plate (1211) on the rod part (121), the rolling shaft (125) swings along with the rod part (121), a roller groove (131) is formed in the swing groove (13) along the swing path of the rolling shaft (125), rollers (126) are rotatably arranged at two ends of the rolling shaft (125), and the rollers (126) are slidably arranged in the roller groove (131).
5. A gravity rod type optical fiber flow detection method is characterized in that: the method is characterized in that a swing groove (13) with an opening at the lower end is arranged in a shell (11), a rod part (121) which is vertically arranged is arranged in the swing groove (13), the upper end of the rod part (121) is hinged with the shell (11), the lower end of the rod part (121) extends out of the opening at the lower end of the swing groove (13), a gravity plate (122) is fixed at the lower end of the rod part (121), the middle section of the rod part (121) is a light shielding plate (1211), a light hole (1212) is arranged in the middle of the light shielding plate (1211), an incident optical fiber (15) and a receiving optical fiber (16) which point to each other are respectively arranged at two opposite sides of the light shielding plate (1211) in the swing groove (13), when the flow rate of fluid is detected, the device is arranged in the fluid, the gravity plate (122) which is vertically arranged in an initial state is vertical to the flow direction of the fluid, the gravity plate (122) is enabled to swing through impact the fluid, so, the output light intensity through the light hole (1212) is changed, the swing angle of the rod part (121) is calculated by detecting the variation of the light intensity, and the magnitude of the fluid pressure acting on the gravity plate (122) is further calculated, so that the value of the flow velocity can be calculated by a fluid mechanics formula, and the flow value is further calculated.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910851439.8A CN110567537A (en) | 2019-09-10 | 2019-09-10 | gravity rod type optical fiber flow sensor and flow detection method thereof |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201910851439.8A CN110567537A (en) | 2019-09-10 | 2019-09-10 | gravity rod type optical fiber flow sensor and flow detection method thereof |
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| CN110567537A true CN110567537A (en) | 2019-12-13 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111948424A (en) * | 2020-07-16 | 2020-11-17 | 新华三技术有限公司 | Wind direction detection system |
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