CN110716272A - DTS system sensing optical cable structure applied to high-temperature detection - Google Patents
DTS system sensing optical cable structure applied to high-temperature detection Download PDFInfo
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- CN110716272A CN110716272A CN201911189531.9A CN201911189531A CN110716272A CN 110716272 A CN110716272 A CN 110716272A CN 201911189531 A CN201911189531 A CN 201911189531A CN 110716272 A CN110716272 A CN 110716272A
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- 230000003287 optical effect Effects 0.000 title claims abstract description 33
- 238000001514 detection method Methods 0.000 title claims abstract description 14
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 96
- 239000013307 optical fiber Substances 0.000 claims abstract description 85
- 239000010410 layer Substances 0.000 claims abstract description 68
- 229910052751 metal Inorganic materials 0.000 claims abstract description 32
- 239000002184 metal Substances 0.000 claims abstract description 32
- 239000000463 material Substances 0.000 claims abstract description 25
- 239000011247 coating layer Substances 0.000 claims abstract description 6
- 230000005540 biological transmission Effects 0.000 claims abstract description 5
- 238000001816 cooling Methods 0.000 claims abstract description 3
- 239000010425 asbestos Substances 0.000 claims description 5
- 229910052895 riebeckite Inorganic materials 0.000 claims description 5
- 238000013461 design Methods 0.000 abstract description 5
- 238000005516 engineering process Methods 0.000 description 6
- 238000009529 body temperature measurement Methods 0.000 description 4
- 239000000835 fiber Substances 0.000 description 4
- 238000005259 measurement Methods 0.000 description 4
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical group O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 229910000838 Al alloy Inorganic materials 0.000 description 1
- 238000001069 Raman spectroscopy Methods 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 238000004880 explosion Methods 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 238000011897 real-time detection Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 235000012239 silicon dioxide Nutrition 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
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- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/44—Mechanical structures for providing tensile strength and external protection for fibres, e.g. optical transmission cables
- G02B6/4401—Optical cables
- G02B6/4429—Means specially adapted for strengthening or protecting the cables
- G02B6/443—Protective covering
-
- 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
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/44—Mechanical structures for providing tensile strength and external protection for fibres, e.g. optical transmission cables
- G02B6/4401—Optical cables
- G02B6/4429—Means specially adapted for strengthening or protecting the cables
- G02B6/4436—Heat resistant
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Measuring Temperature Or Quantity Of Heat (AREA)
Abstract
The invention relates to a DTS system sensing optical cable structure applied to high-temperature detection. The invention comprises an outermost layer for heat conduction, an intermediate layer for cooling, an optical fiber at the innermost layer and a water flowing pipe. The outermost layer is made of metal. The intermediate layer is made of a low heat conduction material. The optical fiber is provided with a coating layer which is used as a temperature sensing medium and an optical transmission medium. The flowing water pipe flows through low-temperature flowing water and is used for taking away part of heat of the low-heat-conduction material, so that the temperature of the optical fiber is lower than that of the outermost layer. The invention has the advantages of simple structure, high temperature resistance, low cost, convenient design and the like.
Description
Technical Field
The invention relates to the field of optical and optical fiber sensing, and discloses a sensing optical cable structure applied to a detectable high-temperature optical fiber temperature sensing (DTS) system based on a distributed optical fiber DTS system theory, on the basis of a traditional single-mode optical fiber, asbestos is added, a constant-temperature flow system is added, and then protection metal is combined.
Background
Distributed optical fiber temperature sensing (DTS) technology has emerged as a means by which temperature sensing is no longer limited to single-point and quasi-distributed sensing. As a long-distance and continuous temperature measuring method. Compared with the traditional temperature sensor, the DTS has the advantages of electromagnetic interference resistance, high-temperature corrosion resistance, explosion and electricity prevention, simplicity in installation, suitability for long-distance and large-area temperature real-time detection and the like. Therefore, the DTS system is widely applied to long-distance security detection, military industry, traffic industry and agriculture.
The complete DTS system is structurally mainly divided into two parts, namely a distributed temperature measurement system host and a sensing optical fiber module, wherein the distributed temperature measurement system host is a complete module integrating a collection card, a light source, a mainboard and a display, the spatial resolution of the DTS and the demodulation of collected signals can be controlled theoretically, the sensing optical fiber system determines the length range of detection, and the temperature bearing capacity of the optical fiber determines the upper limit and the lower limit of the temperature detection of the system.
The optical fiber used in the conventional DTS system mainly uses a conventional optical fiber structure with a coating layer to be directly applied to a detection environment. The material of the optical fiber is silicon dioxide material, but the material of the coating layer is plastic material generally, and the melting point is very low; the fiber can be melted and deformed even the fiber is broken under the condition of high temperature for a long time, and the maximum bearing temperature can not exceed 300 ℃, which limits the application range of the DTS to a great extent.
Disclosure of Invention
Aiming at the defects of the existing DTS system, the invention provides a sensing optical cable structure applied to a high-temperature detection DTS system.
The technical scheme of the invention is as follows:
the invention comprises an outermost layer for heat conduction, an intermediate layer for cooling, an optical fiber at the innermost layer and a water flowing pipe.
The outermost layer is made of metal.
The intermediate layer is made of a low heat conduction material.
The optical fiber is provided with a coating layer which is used as a temperature sensing medium and an optical transmission medium.
The flowing water pipe flows through low-temperature flowing water and is used for taking away part of heat of the low-heat-conduction material, so that the temperature of the optical fiber is lower than that of the outermost layer.
Furthermore, the low heat conduction material is asbestos.
Furthermore, the optical fiber is a single mode optical fiber or a multimode optical fiber.
Furthermore, the plurality of water flowing pipes are axially and symmetrically distributed around the optical fiber.
Furthermore, the flowing water pipe and an external constant-temperature flowing water system form a circulation.
The invention has the beneficial effects that: according to the measured high temperature requirement, different sensing optical cable structures can be designed, the upper limit of the high temperature sensing temperature is the maximum bearing temperature of the metal layer and the low heat conduction material layer, and the water flowing pipes with different quantities and different areas can be designed to keep the temperature of the optical fiber within the bearing temperature range (such as less than 300 ℃). The invention can improve the upper limit of temperature measurement of the DTS system, and the measured temperature can reach 1200 ℃.
Drawings
FIG. 1 is a schematic diagram of a DTS system.
FIG. 2 is a schematic cross-sectional view of a single-flow water pipe sensing optical cable structure.
FIG. 3 is a schematic cross-sectional view of a double-flow water pipe sensing optical cable structure.
FIG. 4 is a schematic cross-sectional view of a three-flow water pipe sensing optical cable structure.
Fig. 5 is a schematic cross-sectional view of a four-flow water pipe sensing optical cable structure.
Detailed Description
The invention designs the structure of the photosensitive fiber on the basis of the DTS technology, adds a constant-temperature water circulation system as shown in figure 1, and forms a complete DTS system together with a distributed temperature measurement system host.
As shown in fig. 2, the sensing optical cable provided by the present invention is a composite structure, and is divided into three layers. The outmost metal level D that is, because metal material has good heat conduction and heat resistance, can come in with ambient temperature transmission to the at utmost, guarantee the accuracy that detects, can play certain guard action to this structure in abominable detection environment simultaneously. The middle layer is a low heat conduction material layer C, the low heat conduction material can be made of asbestos and the like, and the temperature of the high-temperature metal layer is reduced after the high-temperature metal layer passes through the low heat conduction material layer, so that the temperature of the final optical fiber with the coating layer is within the range of the bearable highest temperature. The innermost layer is an optical fiber A and a water flowing pipe B, the optical fiber can be a standard single mode optical fiber or a multimode optical fiber of a communication waveband, and the optical fiber mainly serves as a temperature sensing medium and an optical transmission medium.
The principle of the invention is as follows: when the optical fiber detects the temperature change, the Raman scattering light intensity in the optical fiber is enhanced along with the temperature rise and weakened along with the temperature reduction, and the temperature of the optical fiber can be obtained after demodulation; the flowing water pipe is filled with low-temperature flowing water, so that partial heat of the low-heat-conduction material layer is taken away, and the temperature of the optical fiber is lower than that of the metal layer. The temperature (T) of the optical fiber will be a function of the metal layer temperature (W) given the construction of the sensing cable, keeping the temperature of the water flowing in the flow pipe and the flow velocity. The temperature (T) of the optical fiber can be obtained through the DTS system, so that the temperature (W) of the metal layer is further estimated, and high-temperature sensing is realized.
The embodiment of the invention comprises the following steps:
1. single current water pipe sensing optical cable structure: as shown in FIG. 2, the outermost layer is a metal layer D, which conducts the external temperature and protects the entire structure, which is a concentric ring with an inner radius RD1And an outer radius of RD2(ii) a The middle layer is a low heat conduction material layer C; the innermost layer is an optical fiber A and a water flowing pipe B, the circle centers of the optical fiber A and the metal layer D are the same, and the radius of the optical fiber A is RARadius of the water pipe B is RBThe distance between the centers of the flowing water pipe B and the optical fiber A is RA+RB. The DTS system detects the temperature of the optical fiber, maintains the flow velocity and the water temperature in the flow pipe B under the condition of giving a single-flow water pipe sensing optical cable structure according to a mature calibration technology, and performs temperature calibration on the optical fiber A and the metal layer D in advance; under the actual measurement condition, the temperature of the metal layer D is determined according to the optical fiber temperature detected by the DTS system, so that high-temperature sensing is realized.
2. Double-flow water pipe sensing optical cable structure: as shown in FIG. 3, the outermost layer is a metal layerD, conducting the outside temperature and protecting the whole structure, wherein the structure is a concentric ring with an inner radius RD1And an outer radius of RD2(ii) a The middle layer is a low heat conduction material layer C; the innermost layer is optical fiber A, water flowing pipe B1 and water flowing pipe B2, the circle centers of optical fiber A and metal layer D are the same, and the radiuses of water flowing pipe B1 and water flowing pipe B2 are RB1、RB2The water pipe B1 and the optical fiber A are arranged at the two sides of the optical fiber A respectively, and the distance between the centers of the water pipe B1 and the optical fiber A is RA+RB1The distance between the centers of the flowing water pipe B2 and the optical fiber A is RA+RB2I.e. parallel to the optical fibre and tangential thereto; the distance between the centers of the B1 and the B2 is RA+RB1+RB2. The DTS system detects the temperature of the optical fiber, and maintains the flow velocity and the water temperature in the water flowing pipe B1 and the water flowing pipe B2 under the condition of giving a double-flow water pipe sensing optical cable structure according to a mature calibration technology, and performs temperature calibration on the optical fiber A and the metal layer D in advance; under the actual measurement condition, the temperature of the metal layer D is determined according to the optical fiber temperature detected by the DTS system, so that high-temperature sensing is realized.
3. Three water pipes sensing optical cable structure: as shown in FIG. 4, the outermost layer is a metal layer D, which conducts the external temperature and protects the entire structure, which is a concentric ring with an inner radius RD1And an outer radius of RD2(ii) a The middle layer is a low heat conduction material layer C; the innermost layer is an optical fiber A, a water flowing pipe B1, a water flowing pipe B2 and a water flowing pipe B3, the circle centers of the optical fiber A and the thin metal structure D are the same, and the radiuses of the water flowing pipe B1, the water flowing pipe B2 and the water flowing pipe B3 are RB1、RB2、RB3The distance between the centers of the flowing water pipe B1 and the optical fiber A is RA+RB1The distance between the centers of the flowing water pipe B2 and the optical fiber A is RA+RB2The distance between the centers of the flowing water pipe B3 and the optical fiber A is RA+RB3I.e. parallel to the optical fibre and tangential thereto; the distance between the centers of the water flowing pipe B1 and the water flowing pipe B2 is
The distance between the centers of the water flowing pipe B1 and the water flowing pipe B3 is
The distance between the centers of the water flowing pipe B2 and the water flowing pipe B3 is
The DTS system detects the temperature of the optical fiber, and maintains the flow velocity and the water temperature in the water flowing pipe B1, the water flowing pipe B2 and the water flowing pipe B3 under the condition of giving a three-flow water pipe sensing optical cable structure according to a mature calibration technology, and performs temperature calibration on the optical fiber A and the metal layer D in advance; under the actual measurement condition, the temperature of the metal layer D is determined according to the optical fiber temperature detected by the DTS system, so that high-temperature sensing is realized.
4. Four flowing water pipe sensing optical cable structure: as shown in FIG. 5, the outermost layer is a metal layer D, which conducts the external temperature and protects the entire structure, which is a concentric ring with an inner radius RD1And an outer radius of RD2(ii) a The middle layer is a low heat conduction material layer C; the innermost layer is an optical fiber A, a water flowing pipe B1, a water flowing pipe B2, a water flowing pipe B3 and a water flowing pipe B4, the circle centers of the optical fiber A and the thin metal structure D are the same, and the radiuses of the water flowing pipe B1, the water flowing pipe B2, the water flowing pipe B3 and the water flowing pipe B4 are RB1、RB2、RB3、RB4The distance between the centers of the flowing water pipe B1 and the optical fiber A is RA+RB1The distance between the centers of the flowing water pipe B2 and the optical fiber A is RA+RB2The distance between the centers of the flowing water pipe B3 and the optical fiber A is RA+RB3The distance between the centers of the flowing water pipe B4 and the optical fiber A is RA+RB4I.e. parallel to the optical fibre and tangential thereto; the distance between the centers of the water flowing pipe B1 and the water flowing pipe B2 is
The distance between the centers of the water flowing pipe B1 and the water flowing pipe B3 isThe distance between the centers of the water flowing pipe B2 and the water flowing pipe B3 is
Water flowing pipe B3 and water flowing pipeB4 has a center distance of
The DTS system detects the temperature of the optical fiber, and maintains the flow velocity and the water temperature in the water flow pipe B1, the water flow pipe B2, the water flow pipe B3 and the water flow pipe B4 under the condition of giving a four-water-pipe sensing optical cable structure according to a mature calibration technology, and performs temperature calibration on the optical fiber A and the metal layer D in advance; under the actual measurement condition, the temperature of the metal layer D is determined according to the optical fiber temperature detected by the DTS system, so that high-temperature sensing is realized.
In the above embodiment: the metal layer is made of hard aluminum alloy and used for protecting the sensing optical cable and receiving the temperature detected by the outside, and the thickness of the metal layer is 3 mm. The low thermal conductivity material layer is made of asbestos and is used for reducing the temperature transmitted to the optical fiber, and the thickness of the low thermal conductivity material layer is 10 mm. The optical fiber is common 62.5/125 multimode fiber. The flow velocity of water in the water flowing pipe is controlled by the water flowing pipe through circulation to be 10m/s, so that the temperature of the water in the water flowing pipe is ensured to be constant at 27 ℃. In the designed four-flow-pipe sensing optical cable structure, the positions of the central points of the metal layer, the low heat conduction material and the optical fiber are the same, and the connecting line intersection points of the centers of two opposite flow pipes in the four flow pipes are superposed with the positions of the central points of the optical fiber. After the structure of the four-flow pipe sensing optical cable is determined, a calibration table of complete temperature is obtained through actual test and calibration test of the external temperature and the optical fiber temperature measured by the DTS system, an evolution curve of the optical fiber temperature and the external temperature measured by the designed structure of the four-flow pipe sensing optical cable is obtained through fitting, and the optical fiber temperature measured by the DTS system can be evolved into the temperature of the surface of the metal layer, namely the measured temperature of the external environment through the comparison table and the evolution curve.
The design scheme of the invention includes but is not limited to the four schemes, any sensing optical cable structure which is realized by the combination of the metal layer, the low heat conduction material layer, the water flowing pipe and the optical fiber and is realized by the design principle of the invention is within the protection range, and the invention has the advantages of simple structure, high temperature resistance, low cost, convenient design and the like.
The above description is only an embodiment of the present invention, but the technical features of the present invention are not limited thereto, and any changes or modifications within the field of the present invention by those skilled in the art are covered by the present invention.
Claims (5)
1. DTS system sensing optical cable structure for high temperature detection, its characterized in that: the optical fiber and the water flowing pipe comprise an outermost layer for heat conduction, an intermediate layer for cooling, and an innermost layer;
the outermost layer is made of metal;
the intermediate layer is made of a low heat conduction material;
the optical fiber is provided with a coating layer which is used as a temperature sensing medium and a light transmission medium;
the flowing water pipe flows through low-temperature flowing water and is used for taking away part of heat of the low-heat-conduction material, so that the temperature of the optical fiber is lower than that of the outermost layer.
2. The DTS sensing optical cable structure applied to high temperature detection according to claim 1, wherein: the low heat conduction material is asbestos.
3. The DTS sensing optical cable structure applied to high temperature detection according to claim 1, wherein: the optical fiber is a single mode optical fiber or a multimode optical fiber.
4. The DTS sensing optical cable structure applied to high temperature detection according to claim 1, wherein: the water flow pipes are distributed around the optical fiber in axial symmetry.
5. The DTS system sensing optical cable structure applied to high temperature detection according to any one of claims 1 to 4, wherein: the flowing water pipe and an external constant-temperature flowing water system form a circulation.
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| CN201911189531.9A CN110716272A (en) | 2019-11-28 | 2019-11-28 | DTS system sensing optical cable structure applied to high-temperature detection |
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| CN201911189531.9A CN110716272A (en) | 2019-11-28 | 2019-11-28 | DTS system sensing optical cable structure applied to high-temperature detection |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2012079631A1 (en) * | 2010-12-15 | 2012-06-21 | Abb Technology Ag | High voltage electric cable |
| CN202710820U (en) * | 2012-08-24 | 2013-01-30 | 长沙有色冶金设计研究院有限公司 | 500 DEG C-resistant temperature measurement optical cable |
| CN203551858U (en) * | 2013-11-07 | 2014-04-16 | 河南蓝海通信技术有限公司 | Detection optical cable special for oil tank temperature monitor system |
| CN207123633U (en) * | 2017-06-05 | 2018-03-20 | 德阳汇川科技有限公司 | A kind of sensing optic cable |
| CN210690901U (en) * | 2019-11-28 | 2020-06-05 | 浙江师范大学 | DTS system sensing optical cable structure applied to high-temperature detection |
-
2019
- 2019-11-28 CN CN201911189531.9A patent/CN110716272A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2012079631A1 (en) * | 2010-12-15 | 2012-06-21 | Abb Technology Ag | High voltage electric cable |
| CN202710820U (en) * | 2012-08-24 | 2013-01-30 | 长沙有色冶金设计研究院有限公司 | 500 DEG C-resistant temperature measurement optical cable |
| CN203551858U (en) * | 2013-11-07 | 2014-04-16 | 河南蓝海通信技术有限公司 | Detection optical cable special for oil tank temperature monitor system |
| CN207123633U (en) * | 2017-06-05 | 2018-03-20 | 德阳汇川科技有限公司 | A kind of sensing optic cable |
| CN210690901U (en) * | 2019-11-28 | 2020-06-05 | 浙江师范大学 | DTS system sensing optical cable structure applied to high-temperature detection |
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Application publication date: 20200121 |