CN110296768B - Distributed water temperature measuring device in pipeline - Google Patents
Distributed water temperature measuring device in pipeline Download PDFInfo
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- CN110296768B CN110296768B CN201910612877.9A CN201910612877A CN110296768B CN 110296768 B CN110296768 B CN 110296768B CN 201910612877 A CN201910612877 A CN 201910612877A CN 110296768 B CN110296768 B CN 110296768B
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- light
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
- G01K11/00—Measuring temperature based upon physical or chemical changes not covered by groups G01K3/00, G01K5/00, G01K7/00 or G01K9/00
- G01K11/32—Measuring temperature based upon physical or chemical changes not covered by groups G01K3/00, G01K5/00, G01K7/00 or G01K9/00 using changes in transmittance, scattering or luminescence in optical fibres
Abstract
The invention discloses a distributed water temperature measuring device in a pipeline, which comprises a light source, a coupler, an OTDR and a plurality of temperature sensors, wherein the coupler is used for receiving water temperature; the light source is used for emitting a light signal; the coupler is used for receiving and transmitting optical signals; the temperature sensors are distributed in the pipeline, the temperature sensors are of optical fiber structures with gaps, light signals transmitted in the optical fiber structures change the light intensity of transmitted light when passing through the plane gaps, and the change of the light intensity is used for detecting the change of the water temperature; the OTDR is used for detecting different light intensities reflected by the temperature sensor along with the temperature change, and simultaneously forming a distance and light intensity relation curve graph to reflect the change condition of the water temperature. The optical fiber is used for transmitting optical signals in water, so that the high-requirement waterproof treatment of electronic equipment in water is avoided; the optical fiber has small volume, can be applied to small-sized pipelines (such as floor heating water pipelines), and cannot influence the flow rate of liquid in the pipeline.
Description
Technical Field
The invention belongs to the technical field of water temperature measurement in pipelines, and particularly relates to a distributed water temperature measuring device in a pipeline.
Background
With the promotion of the requirements of energy conservation and environmental protection, for example, in the centralized heating of urban and rural families or a water-cooling circulation system of a power plant, the change of the water temperature in the pipeline can be accurately mastered, so that the real-time monitoring on the temperature can be more effectively carried out. However, the traditional thermistor or thermocouple for the temperature measurement system needs waterproof packaging when used in water, which increases the complexity.
The optical fiber sensor can use an optical fiber as a sensing device and represents the change of temperature according to the change of light transmitted in the optical fiber. Because the optical fiber is made of quartz material, the performance is stable, and the optical fiber can normally transmit optical signals in water, so that waterproof treatment is not needed. Secondly, the optical fiber size is less, uses optical fiber sensor in the pipeline, need not worry the influence of sensor to the water velocity. And the optical fiber sensor is directly laid in the pipeline and is in direct contact with water to be measured, so that the measurement precision is improved.
Disclosure of Invention
The technical problem to be solved by the present invention is to provide a distributed water temperature measuring device in a pipeline, aiming at the defects of the prior art.
In order to achieve the technical purpose, the technical scheme adopted by the invention is as follows:
a distributed water temperature measuring device in a pipeline comprises a light source, a coupler, an Optical Time Domain Reflectometer (OTDR) and a plurality of temperature sensors; the light source is used for emitting a light signal; the coupler is used for receiving and transmitting optical signals; the temperature sensors are distributed in the pipeline, the temperature sensors are of optical fiber structures with gaps, light signals transmitted in the optical fiber structures change the light intensity of transmitted light when passing through the plane gaps, and the change of the light intensity is used for detecting the change of the water temperature; the OTDR is used for detecting different light intensities reflected by the temperature sensor along with temperature changes and simultaneously forming a distance and light intensity relation curve graph, the time for light signals reflected by the temperature sensor is different to form peak values on a reflection spectrum, the position of the peak value is used for positioning the temperature sensor, and the change of the peak value of the reflection peak reflects the change condition of the water temperature at the position.
In order to optimize the technical scheme, the specific measures adopted further comprise:
the light source adopts a semiconductor laser and emits infrared broadband light signals.
The coupler is a three-port directional coupler and is respectively connected with a light source, an OTDR and a temperature sensor; the optical signal emitted by the light source can only be input to the port connected with the temperature sensor, and the optical signal transmitted by the temperature sensor in the reverse direction can only be output from the port connected with the OTDR.
The temperature sensor realizes distributed measurement of water temperature in the pipeline in a mode of connecting a plurality of temperature sensors in series.
The OTDR model mentioned above is TFN F4.
The temperature sensor comprises two optical fibers and a fixed sleeve with a mesh, wherein the optical axes of the two optical fibers are aligned and fixed in the fixed sleeve with the mesh, a gap is reserved in the fixed sleeve for the two optical fibers, and water in a pipeline can flow into the gap between the two optical fibers from the fixed sleeve.
The invention has the following beneficial effects:
1. the optical fiber is used for transmitting optical signals in water, so that the high-requirement waterproof treatment of the electronic equipment in water is avoided;
2. the optical fiber has small volume, can be applied to small-sized pipelines (such as floor heating water pipelines), and cannot influence the flow rate of liquid in the pipeline.
Drawings
FIG. 1 is a schematic structural view of the present invention;
fig. 2 is a schematic structural diagram of a temperature sensor according to an embodiment of the present invention.
Detailed Description
Embodiments of the present invention are described in further detail below with reference to the accompanying drawings.
As shown in fig. 1, the distributed water temperature measuring device in a pipeline of the present invention includes a light source, a coupler, an OTDR and several temperature sensors; the light source is used for emitting a light signal; the coupler is used for receiving and transmitting optical signals; the temperature sensors are distributed in the pipeline, the temperature sensors are of optical fiber structures with gaps, light signals transmitted in the optical fiber structures change the light intensity of transmitted light when passing through the plane gaps, and the change of the light intensity is used for detecting the change of the water temperature; the OTDR is used for detecting different light intensities reflected by the temperature sensor along with temperature changes and simultaneously forming a distance and light intensity relation curve graph, the time for light signals reflected by the temperature sensor is different to form peak values on a reflection spectrum, the position of the peak value is used for positioning the temperature sensor, and the change of the peak value of the reflection peak reflects the change condition of the water temperature at the position.
In an embodiment, as shown in fig. 2, the temperature sensor comprises two optical fibers and a meshed fixture housing, the optical axes of the two optical fibers are aligned and fixed in the meshed fixture housing, and the two optical fibers are spaced in the fixture housing, and water in the pipeline can flow into the gaps in the two optical fibers from the fixture housing.
Core refractive index n1Refractive index of water n2When water with different water temperatures passes through the water-cooling water heater, the Fresnel reflection of the end surface is changed by the change of the refractive index, and the temperature sensing is realized by measuring the change of the light.
According to the fresnel reflection theorem, when light is divided into two polarized lights of a parallel incident plane and a perpendicular incident plane when transmitted at end surfaces having different refractive indexes, if the light is normal incidence, i.e., normal incidence with an incident angle of zero, the reflectivity formula can be expressed as:
when the incident light is natural light, the total reflectance is half of the sum of the vertical and horizontal reflectances, so the total reflectance is:
when the water temperature changes, the refractive index n of the water entering the gap between the end faces of the two optical fibers2Will change, i.e. n2Is a function of the temperature T, and the change rule can be known by looking up a table. The reflectance is therefore also a function of the temperature T according to the above equation, and the change in water temperature can be calculated by measuring the change in reflected light intensity. The reflected light intensity can be expressed as:
in an embodiment, the light source uses a semiconductor laser to emit an infrared broadband light signal.
In an embodiment, the coupler is a three-port directional coupler, and is respectively connected to a light source, an OTDR and a temperature sensor; the optical signal emitted by the light source can only be input to the port connected with the temperature sensor, and the optical signal transmitted by the temperature sensor in the reverse direction can only be output from the port connected with the OTDR.
In an embodiment, the temperature sensor realizes distributed measurement of the water temperature in the pipeline in a series connection mode.
In an embodiment, the OTDR model is TFN F4.
The working principle of the invention is as follows: the light source emits optical signals with certain power, the optical signals are transmitted to the water temperature sensor in the pipeline through the coupler, the Fresnel reflection changes of the plurality of temperature sensors TS caused by the water temperature changes, the reflection spectrum is observed through the OTDR, the position of the horizontal coordinate of the OTDR is marked with the coordinate of the sensor, the vertical coordinate of the OTDR is marked with the reflected light optical power, and the water temperature changes can be known according to the reading of the OTDR reflection peak value changes.
The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above-mentioned embodiments, and all technical solutions belonging to the idea of the present invention belong to the protection scope of the present invention. It should be noted that modifications and embellishments within the scope of the invention may be made by those skilled in the art without departing from the principle of the invention.
Claims (5)
1. A distributed water temperature measuring device in a pipeline is characterized by comprising a light source, a coupler, an OTDR and a plurality of temperature sensors; the light source is used for emitting a light signal; the coupler is used for receiving and transmitting optical signals; the temperature sensors are distributed in the pipeline, the temperature sensors are of optical fiber structures with gaps, light signals transmitted in the optical fiber structures change the light intensity of transmitted light when passing through the plane gaps, and the change of the light intensity is used for detecting the change of the water temperature; the OTDR is used for detecting different light intensities reflected by the temperature sensor along with temperature change and simultaneously forming a distance and light intensity relation curve graph, the time for light signals reflected by the temperature sensor is different to form peak values on a reflection spectrum, the position of the peak value is used for positioning the temperature sensor, and the change of the peak value of the reflection peak reflects the change condition of the water temperature at the position;
the light source adopts a semiconductor laser and emits infrared broadband light signals.
2. The in-pipe distributed water temperature measuring device according to claim 1, wherein the coupler is a three-port directional coupler, and is respectively connected with a light source, an OTDR and a temperature sensor; the optical signal emitted by the light source can only be input to the port connected with the temperature sensor, and the optical signal transmitted by the temperature sensor in the reverse direction can only be output from the port connected with the OTDR.
3. The distributed water temperature measuring device in the pipeline as claimed in claim 1, wherein the temperature sensor realizes the distributed measurement of the water temperature in the pipeline by connecting a plurality of temperature sensors in series.
4. The distributed in-pipe water temperature measurement device of claim 1, wherein said OTDR model is TFN F4.
5. A distributed in-pipe water temperature measuring device as claimed in any one of claims 1 to 4 wherein said temperature sensor comprises two optical fibers and a meshed fixture housing, said two optical fibers being optically aligned and fixed in said meshed fixture housing with a gap in said fixture housing, water in the pipe being flowable from said fixture housing into said gap in said two optical fibers.
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4201446A (en) * | 1978-10-20 | 1980-05-06 | Honeywell Inc. | Fiber optic temperature sensor using liquid component fiber |
| JPS631562B2 (en) * | 1980-01-31 | 1988-01-13 | Tokyo Shibaura Electric Co | |
| CN1374529A (en) * | 2002-04-19 | 2002-10-16 | 清华大学 | Simultaneous in-situ sea water salinity and temperature measuring method and device |
| CN1963400A (en) * | 2006-11-16 | 2007-05-16 | 国家纳米技术与工程研究院 | Fibre optic sensor for measuring temperature and refractive index of liquid contemporarily |
| KR101549699B1 (en) * | 2014-05-12 | 2015-09-03 | 건국대학교 산학협력단 | Sensing unit and optical fiber sensor apparatus comprising the same |
| CN106932026A (en) * | 2017-04-24 | 2017-07-07 | 华中科技大学 | A kind of quasi-distributed seawater thermohaline sensor, measurement apparatus and its method |
| CN109827676A (en) * | 2017-11-23 | 2019-05-31 | 桂林电子科技大学 | The cascade strain sensor array of the heterogeneous optical fiber of single mode |
-
2019
- 2019-07-09 CN CN201910612877.9A patent/CN110296768B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4201446A (en) * | 1978-10-20 | 1980-05-06 | Honeywell Inc. | Fiber optic temperature sensor using liquid component fiber |
| JPS631562B2 (en) * | 1980-01-31 | 1988-01-13 | Tokyo Shibaura Electric Co | |
| CN1374529A (en) * | 2002-04-19 | 2002-10-16 | 清华大学 | Simultaneous in-situ sea water salinity and temperature measuring method and device |
| CN1963400A (en) * | 2006-11-16 | 2007-05-16 | 国家纳米技术与工程研究院 | Fibre optic sensor for measuring temperature and refractive index of liquid contemporarily |
| KR101549699B1 (en) * | 2014-05-12 | 2015-09-03 | 건국대학교 산학협력단 | Sensing unit and optical fiber sensor apparatus comprising the same |
| CN106932026A (en) * | 2017-04-24 | 2017-07-07 | 华中科技大学 | A kind of quasi-distributed seawater thermohaline sensor, measurement apparatus and its method |
| CN109827676A (en) * | 2017-11-23 | 2019-05-31 | 桂林电子科技大学 | The cascade strain sensor array of the heterogeneous optical fiber of single mode |
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