CN103466234A - Sensor device for utilizing fiber bragg grating (FBG) to measure oil weight of oil tank - Google Patents
Sensor device for utilizing fiber bragg grating (FBG) to measure oil weight of oil tank Download PDFInfo
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- CN103466234A CN103466234A CN2013104041862A CN201310404186A CN103466234A CN 103466234 A CN103466234 A CN 103466234A CN 2013104041862 A CN2013104041862 A CN 2013104041862A CN 201310404186 A CN201310404186 A CN 201310404186A CN 103466234 A CN103466234 A CN 103466234A
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Abstract
The invention discloses a sensor device for utilizing fiber bragg grating (FBG) to measure oil weight of an oil tank. The sensor device comprises a liquid level sensor for adopting an FBG optical fiber to detect the liquid level and two density sensors for adopting FBG optical fibers to detect density, wherein the top end of the liquid level sensor is fixed at the top of the oil tank, an elongated liquid level weight regular in shape is vertically lifted at the bottom end of the liquid level sensor, and the bottom end of the liquid level weight is close to the bottom surface of the oil tank. The top ends of the two density sensors are fixed at the top of the oil tank, and an oil level weight soaked on the rated oil quantity top surface of the oil tank and an oil bottom weight soaked at the bottom of the oil tank are respectively lifted at the bottom ends of the density sensors. By density detection of a top layer and a bottom layer of oil and real-time liquid level measurement through the FBG optical fibers, the real-time weight of oil in the oil tank can be obtained finally, the FBG optical fibers are good in strain transmitting effect and suitable for the environments of oil depots and oil wells and the like where electronic sensors are not applicable, the measuring range of the FBG optical fiber can be 20m, measurement accuracy of 0.25%. is achieved, sensor main bodies are not contacted with the oil, good performance can be maintained for a long term, and the sensor device is convenient to install, use, overhaul and replace.
Description
Technical field
The invention belongs to technical field of optical fiber sensing, be specifically related to a kind of FBG(of utilization Fiber Bragg Grating FBG) the heavy sensor device of measurement oil tank oil.
Background technology
LOAD CELLS be take electrical type as main at present, although electrical type LOAD CELLS comparative maturity, but due to the electrical type sensor except needs power supplies, especially can not use under as conditions such as high temperature, deep-etching, high humidity at rugged environment, so be difficult to realize the measurement of some parameters at some special dimension as large-scale oil tank, oil well etc.
The people such as K.O.Hill of Canadian CRC Communications Research Center in 1978 have found the light sensitive characteristic of germnium doped fiber and have produced first optical fiber grating in the world, along with the progress of grating writing technology and the discovery that cryogenic high pressure carries hydrogen sensitization treatment technology afterwards, make the batch manufacturing of optical fiber grating become possibility, it is practical that optical fiber grating starts to move towards, and is widely used in ferry optics comunication and sensory field of optic fibre.Optical fiber grating has been widely used in static state and the dynamic measurement of numerous physical parameters such as strain, temperature, pressure at present, at sensory field, has brought into play important effect.These sensors mainly comprise FBG strain sensor, temperature sensor, acceleration pick-up, displacement pickup etc.
Large-scale oil storage tank in oil field is very big to the demand of oily remeasurement FBG sensor at present, and because its bulky degree of depth is high, environment for use is severe, and never sensor solves the measurement problem that oil is heavy.
Summary of the invention
The objective of the invention is the research difficulty present situation for above-mentioned large-scale oil storage tank oil remeasurement, provide the FBG that utilizes that a kind of high precision and large measuring range is measured to measure the heavy sensor device of oil tank oil, precision can reach 0.25 ‰, and the dark range of oil reaches 20 meters, technique is simple, and reliability is high.
The present invention adopts following technical scheme to realize: a kind of FBG measures the heavy sensor device of oil tank oil, comprise a level sensor 5 that adopts FBG optical fiber to detect liquid level, its top is fixed on oil tank 3 tops, bottom vertically is lifted with the strip shape liquid level weight 6 of regular shape, and the bottom of described liquid level weight 6 approaches the oil tank bottom surface; Two density sensors 1 that adopt FBG optical fiber detection densities, its top all is fixed on oil tank 3 tops, and bottom is lifted with respectively the pasta weight 2 that is immersed in the specified oil mass end face of oil tank and the weight of the oily end 4 of tank bottom.
Described density sensor 1 and level sensor 5 include sensor main body 12 and main FBG detection fiber 15, the top of described sensor main body 12 is provided with fixed orifice 13, and sensor main body 12 is fixing, and its bottom is provided with 16 liftings of weight connecting bore and is immersed in the weight in fluid; Be provided with a vertical straight line groove and be connected and fixed hole 13 and weight connecting bore 16 on sensor main body 12, described main FBG detection fiber 15 fixedly is encapsulated in described groove.
Described density sensor 1 and level sensor 5 all also comprise sensor housing, described sensor main body 12 is fixedly installed in sensor housing, described sensor housing inside is provided with the screw thread fixed leg 11 with fixed orifice 13 couplings, by nut fixation of sensor main body 12, the top of described sensor housing is provided with shell fixing structure 9 density sensor 1 and level sensor 5 is connected with the oil tank top, and bottom is provided with weight and hangs mouth 8 for weight and sensor main body lifting.
The sensor main body 12 at described main FBG detection fiber two ends Shang Xia 15 is provided with strain structure for amplifying 14.
Described strain structure for amplifying 14 is shaped as frame strain structure for amplifying.
The sensor main body 12 of described main FBG detection fiber 15 both sides is provided with the vertical groove of encapsulation fixed temperature compensation FBG optical fiber 17, and described temperature compensating FBG optical fiber 17 be arranged in parallel with main FBG detection fiber 15.
The bottom of described sensor housing is provided with optical fiber and lays mouth 7.
The sensor main body of two density sensors 1 all is fixedly installed in a density sensor housing 18, and two main FBG detection fiber all vertically arrange.
The cylinder that described liquid level weight 6 is even material.
The inner fixation of sensor body of sensor housing, FBG optical fiber is installed on sensor body and connects weight, thereby the variation of the buoyancy of weight is passed to by the strain structure for amplifying centre wavelength that makes FBG on FBG optical fiber and produces the drift variation, realize the detection of buoyancy, then can obtain corresponding data by buoyancy formula F=ρ gV.
After fluid in oil tank is filled, after the fluid molecular motion reaches stable state, the liquid that density is large will sink, density in oil tank evenly diminishes from top to bottom, canful fluid is divided into to the n layer, the number of plies that k is real-time level in the process of draining the oil, level sensor connects a liquid level weight that homogeneous is rectangular, this weight will be immersed in liquid, by the variation of experiencing buoyancy, the change of power will be delivered to oily remeasurement FBG sensor core in the heart, thereby be passed to the upper centre wavelength of FBG that makes of FBG by the strain structure for amplifying again and produce the data that the drift variation detects k layer fluid buoyancy, according to buoyancy formula F=ρ
kthe cubature formula of gV and liquid level weight can draw oil tank real-time level information, simultaneously because fluid density changes, also need to detect the fluid density of liquid level layer, according to buoyancy formula F=ρ gV, two density sensors hang respectively the buoyancy that the fixing regular density weight of two volumes is subject to tank bottom and top oil reservoir, record two limiting density ρ of oil tank inner fluid
1and ρ
n, because fluid is from top to bottom even variation, by ρ
kwith ρ
1, ρ
nrelation bring F=ρ into
kgV, can draw k, transfers the oil tank volume (being specially adapted to oil tank in irregular shape) under the known now liquid level of oil tank data bank, and the fluid weight in the time of can obtaining k layer fluid according to m=ρ V realizes detecting in real time the heavy purpose of oil in oil tank.
The present invention has following beneficial effect.
1.FBG the direct rubber seal of optical fiber is on sensor body, strain transfer is respond well, and sensitivity that can the regulator solution level sensor under structure for amplifying,
2. range can be accomplished 20 meters, reaches 0.25 ‰ survey precision,
3. sensor main body does not contact with liquid, can keep for a long time good performance, and install and use maintenance and change conveniently,
4. simple in structure, the packaging technology of FBG optical fiber is succinct, is applicable to volume production.
Below in conjunction with the drawings and specific embodiments, the present invention will be further described.
The accompanying drawing explanation
Fig. 1 is the transducer arrangement configuration schematic diagram the present invention relates to.
Fig. 2 is the level sensor structural representation.
Fig. 3 is level sensor housing structure schematic diagram.
Fig. 4 is the sensor body structure schematic diagram.
Fig. 5 is density sensor housing structure schematic diagram.
Number in the figure: 1-density sensor, 2-pasta weight, 3-oil tank, 4-oil end weight, 5-level sensor, 6-liquid level weight, 7-optical fiber is laid mouth, and the 8-weight hangs mouth, 9-shell fixing structure, 10-level sensor housing, 11-fixed leg, 12-sensor main body, the 13-fixed orifice, 14-strain structure for amplifying, 15-master FBG detection fiber, 16-weight connecting bore, 17-temperature compensating FBG optical fiber, 18-density sensor housing.
The specific embodiment
Embodiment
Referring to Fig. 1 to Fig. 5, sensor device comprises a level sensor 5 that adopts FBG optical fiber to detect liquid level, and its top is fixed on oil tank 3 tops, and bottom vertically is lifted with the strip shape liquid level weight 6 of regular shape, and the bottom of liquid level weight 6 approaches the oil tank bottom surface; Two density sensors 1 that adopt FBG optical fiber detection density, its top all is fixed on oil tank 3 tops, bottom is lifted with respectively the pasta weight 2 that is immersed in the specified oil mass end face of oil tank and the weight of the oily end 4 of tank bottom, and wherein the pasta weight of top is immersed in the 5mm fluid of the specified oil mass top of oil tank.
Specifically referring to Fig. 1, Fig. 2 and Fig. 4, density sensor 1 and level sensor 5 include sensor main body 12 and main FBG detection fiber 15, the top of sensor main body 12 is provided with fixed orifice 13, and sensor main body 12 is fixing, and its bottom is provided with weight connecting bore 16 connecting hangings and is contained in the weight in fluid; Be provided with a vertical straight line groove and be connected and fixed hole 13 and weight connecting bore 16 on sensor main body 12, main FBG detection fiber 15 fixedly is encapsulated in groove.The sensor main body 12 at main FBG detection fiber two ends Shang Xia 15 is provided with strain structure for amplifying 14, and strain structure for amplifying 14 is for being preferably shaped as frame strain structure for amplifying.The sensor main body 12 of main FBG detection fiber 15 both sides is provided with the vertical groove of encapsulation fixed temperature compensation FBG optical fiber 17, and temperature compensating FBG optical fiber 17 be arranged in parallel with main FBG detection fiber 15.
Wherein, in conjunction with referring to Fig. 3 and Fig. 5, the sensor main body of two density sensors 1 all is fixedly installed in a density sensor housing 18, two main FBG detection fiber all vertically arranges, the sensor main body 12 of level sensor 5 is fixedly installed in level sensor housing 10, density sensor housing 18 and level sensor housing 10 inside are equipped with the screw thread fixed leg 11 with fixed orifice 13 couplings, the middle part of sensor main body 12 is provided with fixed orifice 13 equally, prevent that sensor main body from swinging, fixed leg 11 is by being fixed sensor main body 12 with nut, the top of sensor housing is provided with shell fixing structure 9 density sensor 1 and level sensor 5 is connected with the oil tank top, bottom is provided with weight and hangs mouth 8 for weight and sensor main body lifting.The bottom of density sensor housing 18 and level sensor housing 10 is provided with optical fiber and lays mouth 7.
In the present embodiment, liquid level weight 6 preferably adopts the cylinder of homogeneous material, and the density of liquid level weight and density weight all is greater than the density of fluid, can be immersed in fluid.
The employing following steps of specifically installing and using of the present invention:
1. by without the gel packaged type, main FBG detection fiber being encapsulated on sensor main body, make it in tension, the parallel main FBG detection fiber both sides that are encapsulated into of other two temperature compensating FBG optical fiber, as the temperature compensating grating, form the level sensor core;
2. adopt the method in step 1 to form two density sensor cores;
3. density sensor core and level sensor core are respectively fixed in density sensor housing and level sensor housing, optical fiber is laid mouth by optical fiber and is drawn and fix;
4. density weight and liquid level weight are hanging to respectively to density sensor and level sensor bottom, and weight is placed and is dipped in fluid.
Claims (9)
1. a FBG measures the heavy sensor device of oil tank oil, it is characterized in that: comprise a level sensor (5) that adopts FBG optical fiber to detect liquid level, its top is fixed on oil tank (3) top, bottom vertically is lifted with the strip shape liquid level weight (6) of regular shape, and the bottom of described liquid level weight (6) approaches the oil tank bottom surface;
Two density sensors (1) that adopt FBG optical fiber detection densities, its top all is fixed on oil tank (3) top, and bottom is lifted with respectively the pasta weight (2) that is immersed in the specified oil mass end face of oil tank and the weight of the oily end (4) of tank bottom.
2. a kind of FBG according to claim 1 measures the heavy sensor device of oil tank oil, it is characterized in that: described density sensor (1) and level sensor (5) include sensor main body (12) and main FBG detection fiber (15), the top of described sensor main body (12) is provided with fixed orifice (13), and sensor main body (12) is fixing, and its bottom is provided with weight connecting bore (16) lifting and is immersed in the weight in fluid; Be provided with a vertical straight line groove and be connected and fixed hole (13) and weight connecting bore (16) on sensor main body (12), described main FBG detection fiber (15) fixedly is encapsulated in described groove.
3. a kind of FBG according to claim 2 measures the heavy sensor device of oil tank oil, it is characterized in that: described density sensor (1) and level sensor (5) all also comprise sensor housing, described sensor main body (12) is fixedly installed in sensor housing, described sensor housing inside is provided with the screw thread fixed leg (11) with fixed orifice (13) coupling, by nut fixation of sensor main body (12), the top of described sensor housing is provided with shell fixing structure (9) density sensor (1) and level sensor (5) is connected with the oil tank top, bottom is provided with weight and hangs mouthful (8) for weight and sensor main body lifting.
4. measure the heavy sensor device of oil tank oil according to the described a kind of FBG of claim 2 or 3, it is characterized in that: the sensor main body (12) at the upper and lower two ends of described main FBG detection fiber (15) is provided with strain structure for amplifying (14).
5. a kind of FBG according to claim 4 measures the heavy sensor device of oil tank oil, and it is characterized in that: described strain structure for amplifying (14) is shaped as frame strain structure for amplifying.
6. measure the heavy sensor device of oil tank oil according to the described a kind of FBG of claim 2 or 3, it is characterized in that: the sensor main body (12) of described main FBG detection fiber (15) both sides is provided with the vertical groove of encapsulation fixed temperature compensation FBG optical fiber (17), and described temperature compensating FBG optical fiber (17) be arranged in parallel with main FBG detection fiber (15).
7. a kind of FBG according to claim 3 measures the heavy sensor device of oil tank oil, and it is characterized in that: the bottom of described sensor housing is provided with optical fiber and lays mouthful (7).
8. measure the heavy sensor device of oil tank oil according to the described a kind of FBG of claim 2 or 3, it is characterized in that: the sensor main body of two density sensors (1) all is fixedly installed in a density sensor housing (18), and two main FBG detection fiber all vertically arrange.
9. a kind of FBG according to claim 1 measures the heavy sensor device of oil tank oil, and it is characterized in that: described liquid level weight (6) is the cylinder of even material.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109883882A (en) * | 2019-02-25 | 2019-06-14 | 内蒙古联手创业路桥有限责任公司 | A kind of mud balance detection device for construction of the highway |
| CN110375824A (en) * | 2019-08-22 | 2019-10-25 | 黑龙江大学 | Gas station's tank level and density sensor based on fiber grating |
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| JPH1111582A (en) * | 1997-06-23 | 1999-01-19 | Showa Aircraft Ind Co Ltd | Loading weigh detector of tank lorry |
| CN2423576Y (en) * | 2000-05-08 | 2001-03-14 | 钟安庸 | Ratio liquid level gauge |
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| CN102809521A (en) * | 2012-07-30 | 2012-12-05 | 昆明理工大学 | Float type optical fiber Bragg grating density sensor of Pb-Sn (plumbum-stannum) molten alloy |
| CN202582500U (en) * | 2012-05-03 | 2012-12-05 | 无锡成电光纤传感科技有限公司 | Optical fiber grating strain transducer capable of eliminating external force stretching impact |
| CN203473665U (en) * | 2013-09-06 | 2014-03-12 | 长城信息产业股份有限公司 | Sensor device for measuring oil weight of oil tank through FBG |
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2013
- 2013-09-06 CN CN201310404186.2A patent/CN103466234B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH1111582A (en) * | 1997-06-23 | 1999-01-19 | Showa Aircraft Ind Co Ltd | Loading weigh detector of tank lorry |
| CN2423576Y (en) * | 2000-05-08 | 2001-03-14 | 钟安庸 | Ratio liquid level gauge |
| CN2648416Y (en) * | 2003-10-30 | 2004-10-13 | 关柏鸥 | Fibre-optical grating liquid level sensor |
| CN1743814A (en) * | 2004-09-01 | 2006-03-08 | 关柏鸥 | Optical fiber grating liquid sensor |
| CN101629890A (en) * | 2009-08-17 | 2010-01-20 | 昆明理工大学 | Float type fiber grating liquid densimeter |
| CN202582500U (en) * | 2012-05-03 | 2012-12-05 | 无锡成电光纤传感科技有限公司 | Optical fiber grating strain transducer capable of eliminating external force stretching impact |
| CN102809521A (en) * | 2012-07-30 | 2012-12-05 | 昆明理工大学 | Float type optical fiber Bragg grating density sensor of Pb-Sn (plumbum-stannum) molten alloy |
| CN203473665U (en) * | 2013-09-06 | 2014-03-12 | 长城信息产业股份有限公司 | Sensor device for measuring oil weight of oil tank through FBG |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109883882A (en) * | 2019-02-25 | 2019-06-14 | 内蒙古联手创业路桥有限责任公司 | A kind of mud balance detection device for construction of the highway |
| CN110375824A (en) * | 2019-08-22 | 2019-10-25 | 黑龙江大学 | Gas station's tank level and density sensor based on fiber grating |
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| CN103466234B (en) | 2015-07-08 |
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Address after: 410100 East Third Road, Changsha Economic and Technological Development Zone, Changsha City, Hunan Province Co-patentee after: Changsha HCC HIDEN Technology Co., Ltd. Patentee after: GreatWall Information Industry Co., Ltd. Co-patentee after: Hunan the Great Wall Hai Dun Optical Fiber Technology Co., Ltd. Address before: 410100 East Third Road, Changsha Economic and Technological Development Zone, Changsha City, Hunan Province Co-patentee before: Changsha HCC HIDEN Technology Co., Ltd. Patentee before: GreatWall Information Industry Co., Ltd. Co-patentee before: Hunan Haidun Optical Fiber Sensing Technology Engineering Laboratory Co., Ltd. |
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Effective date of registration: 20190808 Address after: 410205 A076, Headquarters Building of Zhongdian Software Park, 39 Jianshan Road, Changsha High-tech Development Zone, Hunan Province Patentee after: Hunan the Great Wall Hai Dun Optical Fiber Technology Co., Ltd. Address before: 410100 East Road, Changsha economic and Technological Development Zone, Changsha, Hunan, China Co-patentee before: Changsha HCC HIDEN Technology Co., Ltd. Patentee before: GreatWall Information Industry Co., Ltd. Co-patentee before: Hunan the Great Wall Hai Dun Optical Fiber Technology Co., Ltd. |