CN109373915B - Multiphase liquid thickness measurement method and system based on chaotic Brillouin scattering - Google Patents
Multiphase liquid thickness measurement method and system based on chaotic Brillouin scattering Download PDFInfo
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- CN109373915B CN109373915B CN201811360542.4A CN201811360542A CN109373915B CN 109373915 B CN109373915 B CN 109373915B CN 201811360542 A CN201811360542 A CN 201811360542A CN 109373915 B CN109373915 B CN 109373915B
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- G01B11/02—Measuring arrangements characterised by the use of optical techniques for measuring length, width or thickness
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Abstract
The invention discloses a multiphase liquid thickness measuring method and system based on chaotic Brillouin scattering, which comprises the following steps: controlling the different temperatures of different phases of liquid media in the container to enable the junction of the adjacent two phases of liquid media to form temperature mutation; introducing two paths of chaotic lasers at different heights of a liquid medium of a container, wherein one path of chaotic laser generates a Brillouin scattering effect in the liquid medium, and the other path of chaotic laser carries out beat frequency with chaotic Stokes light generated by the Brillouin scattering effect in the liquid medium to obtain a beat frequency spectrum, and each beat frequency spectrum corresponds to a Brillouin frequency shift; if two paths of chaotic lasers are introduced into the junction of two adjacent liquid media, the temperature mutation enables Brillouin frequency shift corresponding to the two paths of chaotic lasers to generate a frequency shift mutation point; and determining the thickness of each phase of liquid medium by determining the height of the liquid medium corresponding to each frequency shift mutation point. The invention can realize the measurement of the thickness of the multi-phase liquid medium.
Description
Technical Field
The invention belongs to the technical field of optical fiber sensing, and particularly relates to a method and a system for measuring thickness of multiphase liquid based on chaotic Brillouin scattering.
Background
The liquid level measurement has important application in the fields of industrial production, petroleum storage and transportation, manufacturing industry and the like, and particularly in the process of petroleum storage and transportation, the accurate measurement of the oil level can greatly improve the economic benefit. In general, the medium in the oil storage tank is composed of gas, crude oil, a water-oil mixing layer, water and impurity layers from top to bottom in sequence. Most oil level measuring devices can only obtain the height of the total liquid, but cannot obtain the specific height of each medium, so that the judgment of the residual oil quantity is influenced, and unnecessary economic loss and potential safety hazards are caused.
Currently, some fuel level sensors based on mechanical, capacitive or magnetostrictive types are mainly used. These sensors are subject to electromagnetic interference, cannot operate in harsh environments, and are very dangerous to introduce electrical signals into the fuel. The optical fiber type oil level sensor has the advantages of corrosion resistance, electromagnetic interference resistance, high sensitivity, high reliability and the like, and is very suitable for measuring multiphase fuel oil.
In recent years, many oil level sensors based on optical fibers have been proposed, such as various oil level sensors of the fiber bragg grating type (long period, etched and tilted gratings), coreless fiber type, and multimode fiber type. These fuel level sensors are generally complex to manufacture, some require etching, are expensive, and have a low measurement range. Since fuel adhesion is a very important problem in oil level measurement, the above measurement methods all have such a problem that accuracy is lowered. The existing oil storage tank is dozens of meters high, the environment is complex, and the layering phenomenon exists in the oil storage tank. However, none of these oil level sensors is capable of measuring multiphase media, and cannot meet the current measurement requirements.
Disclosure of Invention
Aiming at the defects or improvement requirements of the prior art, the invention provides a multiphase liquid measurement method and system based on chaotic Brillouin scattering, so that the technical problems that the conventional optical fiber oil level sensor is complex in manufacturing and high in cost, and has low measurement precision due to the problem of fuel oil adhesion and cannot measure layered multiphase media are solved.
To achieve the above object, according to one aspect of the present invention, there is provided a multiphase liquid thickness measurement method based on chaotic brillouin scattering, the method for measuring heights of different phase liquid medium layers in the same container, comprising:
controlling the different temperatures of different phases of liquid media in the container to enable the junction of the adjacent two phases of liquid media to form temperature mutation;
introducing two paths of chaotic lasers at different heights of a liquid medium of a container, wherein one path of chaotic laser generates a Brillouin scattering effect in the liquid medium, and the other path of chaotic laser carries out beat frequency with chaotic Stokes light generated by the Brillouin scattering effect in the liquid medium to obtain a beat frequency spectrum, and each beat frequency spectrum corresponds to a Brillouin frequency shift; if two paths of chaotic lasers are introduced into the junction of two adjacent liquid media, the temperature mutation enables Brillouin frequency shift corresponding to the two paths of chaotic lasers to generate a frequency shift mutation point;
and determining the thickness of each phase of liquid medium by determining the height of the liquid medium corresponding to each frequency shift mutation point.
Optionally, controlling the temperature difference of different phases of the liquid medium in the vessel comprises the following steps:
measuring the initial temperature of the multi-phase liquid medium at various locations within the vessel;
the multi-phase liquid medium is heated through the self-heating optical fiber, so that the temperatures of different phases of the liquid medium are different.
Optionally, two chaotic lasers are introduced into the liquid medium of the container at different heights, one chaotic laser generates a brillouin scattering effect in the liquid medium, and the other chaotic laser performs beat frequency with chaotic stokes light generated by the brillouin scattering effect in the liquid medium to obtain a beat frequency spectrum, which includes the following steps:
the two chaotic lasers can generate a beat frequency spectrum by adjusting the time delay of the two chaotic lasers and the polarization states of the two chaotic lasers.
According to another aspect of the present invention, there is provided a multi-phase liquid thickness measurement system based on chaotic brillouin scattering, comprising: the device comprises a chaotic laser light source, a first optical amplifier, a 3dB coupler, a first polarization controller, an electro-optical modulator, a sensing optical fiber, a second polarization controller, a programmable delay line, a circulator and a photoelectric detector;
the chaotic laser source is used for emitting chaotic laser, and the emergent end of the chaotic laser source is connected with one end of the first optical amplifier; the first optical amplifier is used for adjusting the optical power of the chaotic laser, and the other end of the first optical amplifier is connected with the input end of the 3dB coupler; the 3dB coupler is used for dividing the chaotic laser after the optical power is adjusted into two paths of chaotic laser with the same power and respectively outputting the two paths of chaotic laser through two emergent ends of the chaotic laser;
one emergent end of the 3dB coupler is connected with one end of the first polarization controller; the first polarization controller is used for adjusting the polarization state of the chaotic laser input to the polarization controller, and the other end of the first polarization controller is connected with one end of the electro-optical modulator; the electro-optical modulator is used for modulating the frequency of the chaotic laser input to the electro-optical modulator; the other end of the optical fiber is connected with one end of the sensing optical fiber; the other end of the sensing optical fiber is connected with the second end of the circulator;
the other emergent end of the 3dB coupler is connected with one end of a second polarization controller; the second polarization controller is used for adjusting the polarization state of the chaotic laser input to the polarization controller, and the other end of the second polarization controller is connected with one end of the programmable delay line; the programmable delay line is used for adjusting the length of the chaotic laser delay line transmitted by the programmable delay line, and the other end of the programmable delay line is connected with the first end of the circulator;
the third end of the circulator is connected with the photoelectric detector;
the first path of chaotic laser transmitted by the electro-optical modulator is transmitted to the sensing optical fiber, and the second path of chaotic laser transmitted by the programmable delay line is transmitted to the sensing optical fiber from the first end of the circulator to the second end of the circulator; when the sensing optical fiber is placed in a liquid medium, the first path of chaotic laser generates a Brillouin scattering effect in the liquid medium, and the second path of chaotic laser carries out beat frequency with chaotic Stokes light generated by the Brillouin scattering effect in the liquid medium by adjusting the time delay of the second path of chaotic laser relative to the first path of chaotic laser to obtain a beat frequency spectrum, wherein each beat frequency spectrum corresponds to a Brillouin frequency shift;
the beat frequency spectrum is transmitted to a photoelectric detector from the second end of the circulator to the third end of the circulator, and the photoelectric detector receives the beat frequency spectrum;
when the temperatures of two adjacent liquid media are different, so that a temperature mutation is formed at the junction of the two adjacent liquid media, if the sensing optical fiber is arranged at the junction of the two adjacent liquid media, the temperature mutation enables Brillouin frequency shift corresponding to the two paths of chaotic lasers to generate a frequency shift mutation point;
and determining the height of the liquid medium corresponding to each frequency shift mutation point by changing the position of the sensing optical fiber in the multi-phase liquid medium, and determining the thickness of each phase of liquid medium.
Optionally, the system further comprises: a self-heating optical fiber;
the self-heating optical fiber is used for heating the liquid medium, so that the temperatures of the two adjacent liquid media are different.
Optionally, the system further comprises: a power meter;
the power meter is used for calibrating the temperature of the liquid medium.
In general, compared with the prior art, the above technical solution contemplated by the present invention can achieve the following beneficial effects:
the method is characterized in that the chaotic Stokes light generated based on the chaotic laser and the Brillouin scattering effect is subjected to beat frequency to obtain a beat frequency spectrum, each beat frequency spectrum corresponds to one Brillouin frequency shift, the Brillouin frequency shift of the beat frequency spectrum generates a mutation point at the temperature mutation position of the liquid medium, and the thickness of each phase of the liquid medium can be determined according to the position of the mutation point.
The invention adopts tunable chaotic laser with low coherence, and can greatly improve the precision of actual measurement without influencing the measurement range due to the characteristic of spatial resolution, and can reach mm level without code modulation.
The invention completely meets the requirement of liquid level measurement in the oil tank because of the system characteristics based on Brillouin and the actual measurement range, namely the sensing distance, is in the meter order.
The measuring system provided by the invention has the advantages of simple structure, high reliability, lower cost and the like.
Drawings
Fig. 1 is a schematic structural diagram of a chaotic brillouin-based multiphase medium liquid measurement system provided by the invention;
FIG. 2 is a schematic structural diagram of a temperature regulation module provided in the present invention;
the same reference numbers will be used throughout the drawings to refer to the same or like elements or structures, wherein: the device comprises a chaotic laser light source 1, a first optical amplifier 2, a 3dB coupler 3, a first polarization controller 4, an electro-optical modulator 5, a sensing optical fiber 6, a second polarization controller 7, a programmable delay line 8, a circulator 9, a photoelectric detector 10, a laser light source 11, a second optical amplifier 12, a self-heating optical fiber 13 and a power meter 14.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.
Based on the method, the multiphase fuel oil measurement system based on the chaotic Brillouin scattering is designed. Due to the characteristic of low coherence, the chaotic laser has great advantages in positioning, and the positioning precision can reach mm level. Meanwhile, the Brillouin scattering optical fiber sensing system has important application in the field of distributed sensing. However, the spatial resolution of the currently adopted brillouin scattering optical fiber sensing system is less than 1m, and the currently adopted brillouin scattering optical fiber sensing system cannot meet the current measurement requirements more and more. The method combines the advantages of the chaotic laser and the Brillouin scattering technology, and can form a distributed multi-phase medium liquid level optical fiber sensing system with high resolution (mm). The measuring system has the characteristics of large range, low cost, high precision, high reliability and the like.
The multiphase liquid thickness measuring system provided by the invention can be applied to a multiphase fuel oil measuring system, can effectively solve the problems that the traditional liquid level measuring system cannot measure a multiphase measuring target, has a small measuring range and low measuring resolution, and has good applicability to the actual environment measuring problems such as multiphase measurement in an oil tank and the like.
In order to meet the requirements, the invention provides a multiphase fuel oil measurement system based on chaotic Brillouin.
As shown in fig. 1, the liquid level measurement module mainly comprises a chaotic laser light source 1, a first optical amplifier 2, a 3dB coupler 3, a first polarization controller 4, an electro-optical modulator 5, a sensing optical fiber 6, a second polarization controller 7, a programmable delay line 8, a circulator 9, a photodetector 10, and the like, wherein the position of brillouin scattering occurring in the sensing optical line is selected by adjusting the length of the delay line.
As shown in fig. 2, the temperature control module mainly comprises a laser light source 11, a second optical amplifier 12, a self-heating optical fiber 13, a power meter 14, and the like.
The emergent end of the chaotic laser source 1 is connected with one end of the first optical amplifier 2, so that the optical power is improved; the other end of the first optical amplifier 2 is connected with the input end of the 3dB coupler 3, and the signal light is divided into detection light and reference light; one emergent end of the 3dB coupler 3 is connected with the first polarization controller 4 to adjust the polarization state of the output light; the other end of the first polarization controller 4 is connected with an electro-optical modulator 5 to modulate the frequency of the detection light; the other end of the electro-optical modulator 5 is connected with a sensing optical fiber 6; one end of the sensing optical fiber 6 is connected with the second end of the circulator 9; the other emergent end of the 3dB coupler is connected with a second polarization controller 7; the other end of the second polarization controller 7 is connected with a programmable delay line 8, and the programmable delay line 8 can automatically adjust the length of the delay line; the other end of the programmable delay line 8 is connected with the first end of the circulator 9; the third end of the circulator 9 is connected with a photoelectric detector 10.
The chaotic laser source is generated by disturbing the laser through adding light feedback outside the broadband laser source, and the line width and the power of the chaotic laser can be adjusted by adjusting the optical attenuator and the polarization controller in the feedback loop, so that the expected coherence of the laser source is achieved. The chaotic laser emitted by the chaotic laser source is subjected to power amplification through a first optical amplifier, namely a high-power erbium-doped optical fiber amplifier, and is divided into a sensing optical path and a reference optical path after passing through a 3dB coupler, and the polarization states of the two paths of light are controlled by two polarization controllers respectively so as to achieve a better beat frequency effect. The chaotic laser of the sensing arm is subjected to frequency modulation through the electro-optical modulator and then injected into the sensing optical fiber to generate a Brillouin scattering effect. The chaotic laser of the reference arm is injected into the sensing optical fiber through the adjustable delay line and the circulator again to perform beat frequency with the chaotic Stokes light generated by Brillouin scattering, a beat frequency signal is received by the photoelectric detector through the circulator, so that a beat frequency spectrum is obtained, and then the demodulation of Brillouin frequency shift is performed in the later signal processing. Thereby obtaining liquid level information. The sensing arm refers to a loop in which the detection light is located, and the reference arm refers to a loop in which the reference light is located.
Wherein the sensing fiber is a common single mode fiber.
The emergent end of the laser light source 11 is connected with one end of the second optical amplifier 12, so that the optical power is improved; the other end of the second optical amplifier 12 is connected with a self-heating optical fiber 13; the other end of the self-heating optical fiber 13 is communicated with the power meter 14, and the sensing optical fiber 6 and the self-heating optical fiber 13 are arranged in parallel at an interval of 20 mm.
Specifically, the sensing optical fiber 6 and the self-heating optical fiber 13 are both placed in a liquid medium, the self-heating light 13 is placed in the liquid medium for heating, and the sensing optical fiber 6 is placed in the liquid medium for detecting the thickness of the liquid.
The laser light source 11 is a broad-spectrum continuous laser source, and after being emitted, the laser light source is subjected to power amplification through a second optical amplifier, namely a high-power erbium-doped fiber amplifier, and is injected into the self-heating fiber 13 to perform a heating effect on the sensing fiber 6, and finally, the temperature is calibrated through a power meter.
The self-heating optical fiber 13 is a single-mode optical fiber with a core doped with more cobalt and germanium and a larger light absorption rate to generate photothermal conversion.
The basic principle of the chaotic Brillouin-based multiphase liquid medium thickness measurement system is as follows: in the initial state, the temperatures of different media in the liquid tank are the same, but the heat conductivity coefficients of the different media are different. When the self-heating optical fiber converts the light energy of the laser light source into heat energy and generates heat in the medium, the temperature changes of different media are different, so that a temperature jump is formed at the junction of the two media. The method comprises the steps of placing a sensing optical fiber in liquid to be measured, changing the optical path of a reference arm by adjusting an adjustable delay line, accurately positioning the position of stimulated Brillouin scattering in the sensing optical fiber, and obtaining Brillouin frequency shift of each position on the optical fiber through frequency sweeping. The temperature changes of the positions correspond to one another, so that in the obtained curve of the Brillouin frequency shift changing along with the positions, the mutation points are interfaces of two different media. Because the coherence length of the chaotic laser is very short, the actual measurement precision can reach 1 mm. The method can obtain the thickness of each dielectric layer in the multi-phase medium, and has important significance in practical application.
As shown in fig. 1 and 2, the components 1-14 are assembled according to the figure. The initial temperature of each position of the measured multi-phase medium is firstly measured, then the multi-phase medium is heated through the self-heating optical fiber, and the temperatures of different media are different at the moment due to the fact that the thermal conductivities of the different media are different. And then adjusting the length and the frequency sweep of the adjustable delay line to obtain the Brillouin frequency shift of each position on the optical fiber, wherein the Brillouin frequency shift mutation point is a temperature mutation point as each point on the optical fiber corresponds to the temperature of the point, and the temperature mutation point corresponds to an interface of two media. Therefore, the positions of the media are distinguished, and then the thickness distribution of each medium layer is obtained.
It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (3)
1. A multiphase liquid thickness measurement method based on chaotic Brillouin scattering is used for measuring the heights of different phase liquid medium layers in the same container, and is characterized by comprising the following steps:
controlling the different temperatures of different phases of liquid media in the container to enable the junction of the adjacent two phases of liquid media to form temperature mutation; measuring the initial temperature of the multi-phase liquid medium at various locations within the vessel; heating the multi-phase liquid medium through the self-heating optical fiber to enable the temperatures of the liquid media of different phases to be different;
introducing two paths of chaotic lasers at different heights of a liquid medium of a container, wherein one path of chaotic laser generates a Brillouin scattering effect in the liquid medium, and the other path of chaotic laser carries out beat frequency with chaotic Stokes light generated by the Brillouin scattering effect in the liquid medium to obtain a beat frequency spectrum, and each beat frequency spectrum corresponds to a Brillouin frequency shift; if two paths of chaotic lasers are introduced into the junction of two adjacent liquid media, the temperature mutation enables Brillouin frequency shift corresponding to the two paths of chaotic lasers to generate a frequency shift mutation point; the two chaotic lasers generate a beat frequency spectrum by adjusting the time delay of the two chaotic lasers and the polarization states of the two chaotic lasers;
and determining the thickness of each phase of liquid medium by determining the height of the liquid medium corresponding to each frequency shift mutation point.
2. A multiphase liquid thickness measurement system based on chaotic Brillouin scattering is characterized by comprising: the device comprises a chaotic laser light source (1), a first optical amplifier (2), a 3dB coupler (3), a first polarization controller (4), an electro-optical modulator (5), a sensing optical fiber (6), a second polarization controller (7), a programmable delay line (8), a circulator (9) and a photoelectric detector (10);
the chaotic laser source (1) is used for emitting chaotic laser, and the emergent end of the chaotic laser source is connected with one end of the first optical amplifier (2); the first optical amplifier (2) is used for adjusting the optical power of the chaotic laser, and the other end of the first optical amplifier is connected with the input end of the 3dB coupler (3); the 3dB coupler (3) is used for dividing the chaotic laser after the optical power is adjusted into two paths of chaotic laser with the same power and respectively outputting the two paths of chaotic laser through two emergent ends of the chaotic laser;
one emergent end of the 3dB coupler (3) is connected with one end of the first polarization controller (4); the first polarization controller (4) is used for adjusting the polarization state of the chaotic laser input to the polarization controller, and the other end of the first polarization controller (4) is connected with one end of the electro-optical modulator (5); the electro-optical modulator (5) is used for modulating the frequency of the chaotic laser input to the electro-optical modulator; the other end of the optical fiber is connected with one end of a sensing optical fiber (6); the other end of the sensing optical fiber (6) is connected with the second end of the circulator (9);
the other emergent end of the 3dB coupler is connected with one end of a second polarization controller (7); the second polarization controller (7) is used for adjusting the polarization state of the chaotic laser input to the polarization controller, and the other end of the second polarization controller (7) is connected with one end of a programmable delay line (8); the programmable delay line (8) is used for adjusting the length of a chaotic laser delay line transmitted by the programmable delay line (8), and the other end of the programmable delay line (8) is connected with the first end of the circulator (9);
the third end of the circulator (9) is connected with a photoelectric detector (10);
a first path of chaotic laser transmitted by the electro-optical modulator (5) is transmitted to the sensing optical fiber (6), and a second path of chaotic laser transmitted by the programmable delay line (8) is transmitted to the sensing optical fiber (6) from the first end of the circulator (9) to the second end of the circulator (9); when the sensing optical fiber (6) is placed in a liquid medium, the first path of chaotic laser generates a Brillouin scattering effect in the liquid medium, the second path of chaotic laser carries out beat frequency with chaotic Stokes light generated by the Brillouin scattering effect in the liquid medium by adjusting the time delay of the second path of chaotic laser relative to the first path of chaotic laser, so that a beat frequency spectrum is obtained, and each beat frequency spectrum corresponds to a Brillouin frequency shift;
the beat frequency spectrum is transmitted to a photoelectric detector (10) from the second end of the circulator (9) to the third end of the circulator (9), and the photoelectric detector (10) receives the beat frequency spectrum;
when the temperatures of two adjacent liquid media are different, so that a temperature mutation is formed at the junction of the two adjacent liquid media, if the sensing optical fiber (6) is arranged at the junction of the two adjacent liquid media, the temperature mutation enables Brillouin frequency shift corresponding to the two paths of chaotic lasers to generate a frequency shift mutation point;
determining the height of the liquid medium corresponding to each frequency shift mutation point by changing the position of the sensing optical fiber (6) in the multi-phase liquid medium, and determining the thickness of each phase of liquid medium;
a self-heating optical fiber (13); the self-heating optical fiber (13) is used for heating the liquid medium, so that the temperatures of the two adjacent liquid media are different.
3. The chaotic brillouin scattering-based multi-phase liquid thickness measurement system of claim 2, further comprising: a power meter (14);
the power meter (14) is used for calibrating the temperature of the liquid medium.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5293213A (en) * | 1992-08-12 | 1994-03-08 | Klein Uwe K A | Utilization of a modulated laser beam in heterodyne interferometry |
| DE69126506D1 (en) * | 1990-11-30 | 1997-07-17 | Canon Kk | Device for displacement or speed measurement |
| CN101226087A (en) * | 2007-01-18 | 2008-07-23 | 武汉晟思高新技术有限公司 | Photo-electric optical fiber temperature sensing device |
| CN101787882A (en) * | 2010-02-11 | 2010-07-28 | 哈尔滨工业大学 | Optical time domain reflection (OTDR) distributed optical fiber sensing system based on Brillouin scattering and subsurface temperature monitoring method using same |
| CN105136177A (en) * | 2015-08-27 | 2015-12-09 | 太原理工大学 | Sub-millimeter spatial resolution distributed optical fiber sensing device and method |
| CN106404121A (en) * | 2016-12-02 | 2017-02-15 | 哈尔滨理工大学 | Optical fiber liquid level measurement device and method |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102721484B (en) * | 2012-06-08 | 2014-07-23 | 浙江中欣动力测控技术有限公司 | Distributed optical fiber sensing device based on brillouin scattering |
-
2018
- 2018-11-15 CN CN201811360542.4A patent/CN109373915B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE69126506D1 (en) * | 1990-11-30 | 1997-07-17 | Canon Kk | Device for displacement or speed measurement |
| US5293213A (en) * | 1992-08-12 | 1994-03-08 | Klein Uwe K A | Utilization of a modulated laser beam in heterodyne interferometry |
| CN101226087A (en) * | 2007-01-18 | 2008-07-23 | 武汉晟思高新技术有限公司 | Photo-electric optical fiber temperature sensing device |
| CN101787882A (en) * | 2010-02-11 | 2010-07-28 | 哈尔滨工业大学 | Optical time domain reflection (OTDR) distributed optical fiber sensing system based on Brillouin scattering and subsurface temperature monitoring method using same |
| CN105136177A (en) * | 2015-08-27 | 2015-12-09 | 太原理工大学 | Sub-millimeter spatial resolution distributed optical fiber sensing device and method |
| CN106404121A (en) * | 2016-12-02 | 2017-02-15 | 哈尔滨理工大学 | Optical fiber liquid level measurement device and method |
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