CN109239011A - A kind of optical fiber dewpoint humidity detection device, system and its control method - Google Patents
A kind of optical fiber dewpoint humidity detection device, system and its control method Download PDFInfo
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- CN109239011A CN109239011A CN201810801296.5A CN201810801296A CN109239011A CN 109239011 A CN109239011 A CN 109239011A CN 201810801296 A CN201810801296 A CN 201810801296A CN 109239011 A CN109239011 A CN 109239011A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/41—Refractivity; Phase-affecting properties, e.g. optical path length
Abstract
The present invention relates to sensor control technology fields, specifically disclose a kind of optical fiber dewpoint humidity detection device, including the first optical fiber, humidity sensing layer, the second optical fiber, the first fiber coupler, the second fiber coupler, third fiber coupler, light source, the first light power meter and the second light power meter；The present invention discloses a kind of optical fiber dewpoint humidity detection system, including optical fiber dewpoint humidity detection device, computing controller, data collector, temperature sensor, refrigerator and actuator as described above again.The present invention discloses a kind of control method of optical fiber dewpoint humidity detection system again, comprising: S1 cools down；S2 acquires real time data；Acquisition data are passed to computing controller by S3；S4, processing obtain refractive index-time graph and temperature-time curve；There is the temperature value of condensation in S5, judgement；S6 calculates relative humidity.The present invention has the advantages that measuring accuracy is high, easy to operate, stable, environment-adapting ability is high.
Description
Technical field
The present invention relates to sensor control technology fields, and in particular to a kind of optical fiber dewpoint humidity detection device, system and
Its control method.
Background technique
With the rapid development of all conglomeraties such as industry, aquaculture, national defence, environment measuring, aerospace, food processing,
Requirement to the air water content in manufacturing process is also increasingly finer, therefore the measurement and control of ambient humidity also seem especially
It is important.Correspondingly to the weight such as the sensitivity of humidity sensor, response time, measurement range, repeatability, humidity hysteresis, temperature characterisitic
Index is wanted to also proposed higher standard.
Traditional moisture instruments has wet-and-dry bulb hygrometer, mechanical type hygrometer and electron type humidity sensor etc..It passes
The humidity sensor of system is since structure is simple, technical threshold is low, the advantages such as low in cost are used in certain fields of measurement.Its
In, electron type humidity sensor is applied than wide, and occupation rate of market is very high, in measurement sensitivity, range and precision aspect
Advantage is prominent.But traditional sensor still has some drawbacks, for example, interchangeability and long-time stability it is poor, it is not easy to directly replace
It changes, it is short and can not (such as serious pollution, forceful electric power magnetic environment, inflammable easy in harsh environment itself to respond humidity hysteresis, drift, service life
It is quick-fried etc.) it uses, cause it to be restricted in fields such as high temperature and pressure engineering, nuclear fuels, it is difficult to effectively measurement humidity.
Summary of the invention
In view of this, it is necessary to for above-mentioned problem, propose that a kind of optical fiber dewpoint humidity detection device, optical fiber dew point are wet
The control method of detection system and the optical fiber dewpoint humidity detection system based on virtual instrument is spent, to solve above-mentioned background technique
In conventional moisture measuring instrument the shortcomings that: interchangeability is poor, long-time stability are poor, the service life is short and environment-adapting ability is low.
To achieve the above object, the present invention takes technical solution below:
A kind of optical fiber dewpoint humidity detection device include: the first optical fiber, humidity sensing layer, the second optical fiber, the first fiber coupler,
Second fiber coupler, third fiber coupler, light source, the first light power meter and the second light power meter；
One end of first optical fiber is coated with humidity sensing layer, and is set in the environment space for carrying out temperature adjusting；First light
One end of the fine other end and the first fiber coupler carries out guide-lighting connection；The other end and third optical fiber of first fiber coupler
One end of coupler carries out guide-lighting connection；
One end of second optical fiber is set in the environment space of the not formed dew point of air；The other end of second optical fiber and
One end of two fiber couplers carries out guide-lighting connection；One end of the other end of second fiber coupler and third fiber coupler into
The guide-lighting connection of row；
The other end and light source of the third fiber coupler carry out guide-lighting connection；First light power meter and the first optical fiber coupling
Clutch carries out guide-lighting connection；Second light power meter and the second fiber coupler carry out guide-lighting connection；
First optical fiber is used to detect the humidity for the Experimental Area that air forms dew point；
The humidity sensing layer is used to absorb the air moisture of the Experimental Area, and changes the refractive index of the first optical fiber；
Second optical fiber is used to detect the humidity of the environment of the not formed dew point of air；
Light splitting connector of first fiber coupler as the first optical fiber and the first light power meter；Second optical fiber
Light splitting connector of the coupler as the second optical fiber and the second light power meter；The third fiber coupler is as the first optical fiber coupling
The light splitting connector of clutch, the second fiber coupler and light source；
The light source is used for while providing the light of same luminance to the first optical fiber and the second optical fiber；
First light power meter is used to acquire the real time data of the refractive index of the first optical fiber；
Second light power meter is used to acquire the real time data of the refractive index of the second optical fiber.
Further, the humidity sensing layer is lithium chloride-polyvinyl alcohol humidity sensitive thin film.
Further, the light source is laser semiconductor light source.
Further, first light power meter and the second light power meter are designed with power digital display device.
Further, first light power meter and the second light power meter are designed with RS-232 interface.
A kind of optical fiber dewpoint humidity detection system includes: optical fiber dewpoint humidity detection device as described above, calculates control
Device, data collector, temperature sensor, refrigerator and actuator；Computing controller respectively with data collector, the first optical power
Meter, the second light power meter are attached；Actuator is electrically connected with data collector, refrigerator respectively；First light
Fine one end or in the refrigeration space that refrigerator is formed；
The computing controller exports corresponding control instruction for reading, handling and analysis detecting data；
The data collector is used to read the detection data of temperature sensor, and is controlled according to the instruction of computing controller
Actuator；
The temperature sensor is used to detect the environment temperature of the refrigeration space of refrigerator formation, and will test data transmission
To data collector；
The refrigerator is used to carry out refrigeration cool-down to the refrigeration space for being equipped with the first optical fiber；
The actuator is for controlling the start and stop of refrigerator and/or operating power.
Further, the computing controller distinguishes the first light power meter, the second optical power by RS-232 communication protocol
Meter is attached.
Further, the computing controller is equipped with a calculation control module；The calculation control module includes light function
Rate meter setup module, carrying out shake communication module, temperature collecting module, dew point judgment module, refractive index computing module, data save mould
Plate and virtual display module；
The light power meter setup module is used to send parameter setting life to the first light power meter and/or the second light power meter
It enables and/or reading is ordered, and read the response cue of the first light power meter and/or the second light power meter；
The carrying out shake communication module is used to detect the connection status of the first light power meter and/or the second light power meter；
The temperature collecting module is used for the real time temperature data of temperature collection sensor；
The dew point judgment module according to the real time temperature data of temperature collecting module for calculating and judging refrigerator
The dew point of the refrigeration space of formation forms moment and temperature value；
The refractive index computing module is used for the power number according to the magnitude of power of the first light power meter, the second light power meter
The index meter of value, the refractive index of air and fiber core calculates the refractive index of humidity sensing layer；
The data save template for saving to the data of temperature collecting module and refractive index computing module；
The virtual display module be used to virtually show the control process of the computing controller, data variation process and
Parameter setting procedure.
Further, the computing controller is also equipped with a LabVIEW software systems.
A kind of control method of optical fiber dewpoint humidity detection system is applied to optical fiber dewpoint humidity detection system as described above
System, the control method the following steps are included:
S1, computing controller cool down to the refrigeration space for being equipped with the first optical fiber by control refrigerator；
S2, the first light power meter acquire the real time data of the refractive index of the first optical fiber；Second light power meter acquires the second light
The real time data of fine refractive index；The real time data of temperature sensor temperature collection；
S3, the first light power meter, the second light power meter, temperature sensor will acquire data and be passed to computing controller；
S4, computing controller carries out temperature control to refrigerator, and the LabVIEW by being installed in computing controller is soft
Part system handles to obtain refractive index-time graph and temperature-time curve；
S5, computing controller judge the system equipped with the first optical fiber by analytical refraction rate-time graph knee of curve
The temperature value of the appearance condensation in cold space；
S6, computing controller handle the data of temperature collecting module, it is made to be transformed into corresponding temperature refraction rate
It is worth and corresponding relative humidity at room temperature is calculated.
The invention has the benefit that
The present invention has the characteristics that human-computer interaction interface close friend, real-time detection, storage and alarm, flexible setting for parameters；It is real
Verify that bright system run all right, easy to operate, precision is high, at low cost, strong antijamming capability can be applied to many Humidity Detections necks
Domain.There is the present invention small in size, light-weight, electromagnetism interference, response to change, and big, electrical insulation capability is good, corrosion-resistant, Measurement bandwidth
It is very wide, suitable for inflammable and explosive hazardous environment and be easy to implement Distributed Multi measurement the advantages that, be widely used in modern workers and peasants
Industry and sciemtifec and technical sphere.The present invention collects data by the communication with fibre optical sensor using LABVIEW software systems, and
In virtual oscillograph interface display, dynamic observation experiment data process can be shown in real time, user can pass through close friend's
The computer that pattern manipulation interface is shown completes the entirely test work such as acquisition, analysis, processing, display, storage of measurement data
Make, and is remotely monitored and data sharing by network implementations.The present invention can accurately measure the humidity of gas in environment, and to ring
Border is of less demanding, reproducible, and error is small, is widely portable to measurement and monitoring of the every field to humidity.
Detailed description of the invention
Fig. 1 is a kind of structural schematic diagram of optical fiber dewpoint humidity detection device of the invention；
Fig. 2 is a kind of structural schematic diagram of optical fiber dewpoint humidity detection system of the invention；
Fig. 3 is the structural schematic diagram of calculation control module of the invention；
Fig. 4 is a kind of work flow diagram of the control method of optical fiber dewpoint humidity detection system of the invention；
Fig. 5 is the program chart based on LABVIEW software systems about the judgement of condensation point of the invention in S5；
Fig. 6 is the program chart based on LABVIEW software systems of the invention that calculate about refractive index in S4；
Fig. 7 is the process block based on LABVIEW software systems saved about data that data of the invention save template
Figure；
Virtual display interface when Fig. 8 is the appearance temperature inflection point of virtual display module of the invention；
Virtual display interface when Fig. 9 is the progress repeated experiment of virtual display module of the invention；
Figure 10 is a kind of operation principle schematic diagram of optical fiber dewpoint humidity detection device of the invention；
Figure 11 is a kind of calculating process schematic diagram of the control method of optical fiber dewpoint humidity detection system of the invention；
Figure 12 is a kind of program form figure of the control method of optical fiber dewpoint humidity detection system of the invention；
Description of symbols:
First optical fiber 1；Humidity sensing layer 2；Second optical fiber 3；First fiber coupler 4；Second fiber coupler 5；Third optical fiber
Coupler 6；Light source 7；First light power meter 8；Second light power meter 9；Computing controller 10；Data collector 11；Temperature sensing
Device 12；Refrigerator 13；Actuator 14；Light power meter setup module 15；Carrying out shake communication module 16；Temperature collecting module 17；Dew point
Judgment module 18；Refractive index computing module 19；Data save template 20；Virtual display module 21.
Specific embodiment
To make the object, technical solutions and advantages of the present invention clearer, below in conjunction with the embodiment of the present invention, to this hair
Bright technical solution work further clearly and completely describes.It should be noted that described embodiment is only the present invention one
Section Example, instead of all the embodiments.Based on the embodiments of the present invention, those of ordinary skill in the art are not doing
Every other embodiment obtained under the premise of creative work out, shall fall within the protection scope of the present invention.
It is to be appreciated that the orientation or positional relationship of the instructions such as term " on ", "lower", "front", "rear", "left", "right"
To be based on the orientation or positional relationship shown in the drawings, be merely for convenience of description of the present invention and simplification of the description, rather than indicate or
It implies that signified device or element must have a particular orientation, be constructed and operated in a specific orientation, therefore should not be understood as
Limitation of the present invention.
The terms such as " first ", " second ", " third " are used for description purposes only, and are not understood to indicate or imply relatively heavy
The property wanted or the quantity for implicitly indicating indicated technical characteristic.Define " first " as a result, " second ", " third " feature can
To explicitly or implicitly include one or more of the features.
Embodiment
As shown in Figure 1, a kind of optical fiber dewpoint humidity detection device includes: the first optical fiber 1, humidity sensing layer 2, the second optical fiber 3,
One fiber coupler 4, the second fiber coupler 5, third fiber coupler 6, light source 7, the first light power meter 8 and the second optical power
Meter 9；
One end of first optical fiber 1 is coated with humidity sensing layer 2, and is set in the environment space for carrying out temperature adjusting；First
One end of the other end of optical fiber 1 and the first fiber coupler 4 carries out guide-lighting connection；The other end of first fiber coupler 4 and
One end of three fiber couplers 6 carries out guide-lighting connection；
One end of second optical fiber 3 is set in the environment space of the not formed dew point of air；The other end of second optical fiber 3 with
One end of second fiber coupler 5 carries out guide-lighting connection；The other end of second fiber coupler 5 and third fiber coupler 6
One end carries out guide-lighting connection；
The other end and light source 7 of the third fiber coupler 6 carry out guide-lighting connection；First light power meter 8 and the first light
Fine coupler 4 carries out guide-lighting connection；Second light power meter 9 and the second fiber coupler 5 carry out guide-lighting connection；
First optical fiber 1 is used to detect the humidity for the Experimental Area that air forms dew point；
The humidity sensing layer 2 is used to absorb the air moisture of the Experimental Area, and changes the refractive index of the first optical fiber 1；
Second optical fiber 3 is used to detect the humidity of the environment of the not formed dew point of air；
Light splitting connector of first fiber coupler 4 as the first optical fiber 1 and the first light power meter 8；Described second
Light splitting connector of the fiber coupler 5 as the second optical fiber 3 and the second light power meter 9；The third fiber coupler 6 is as the
The light splitting connector of one fiber coupler 4, the second fiber coupler 5 and light source 7；
The light source 7 is used for while providing the light of same luminance to the first optical fiber 1 and the second optical fiber 3；
First light power meter 8 is used to acquire the real time data of the refractive index of the first optical fiber 1；
Second light power meter 9 is used to acquire the real time data of the refractive index of the second optical fiber 3.
Specifically, the power that the first light power meter 1 and the second light power meter 3 use is calculated as RS-232 interface, data transmission
Basic command mode be master-slave mode, i.e., computing controller be issue order main body, to each power meter transmission various parameters set
Order or reading order are set, power meter, which receives, orders and make response, gets in touch with by RTS/CTS request-reply in RS-232 interface
Signal makees sender for the switching in half-duplex MODEM system between sending method and reception mode in full duplex system
Switching between formula and reception mode, last power meter be passed back to the corresponding answer signal of computing controller (can be PC machine) or
Data；Its serial ports parameter setting are as follows: baud rate --- 57600b/s；No parity check；8 data bit；1 stop position；Acquire data
The preceding wavelength by each light power meter is set as 1550nm, and the resource name of VISA wants corresponding.
Specifically, humidity sensing layer 2 is obtained using following methods:
2 making step of humidity sensing layer is as follows:
(1) wet-sensitive liquid: under the conditions of 20 DEG C of temperature, 10ml deionized water dissolving lithium chloride is made into saturated solution；Later will
1g polyvinyl alcohol, 12ml deionized water, 16ml ethyl alcohol, 0.18ml lithium chloride saturated solution are sufficiently mixed to obtain wet-sensitive liquid；
(2) it cleans optical fiber: carrying out disinfection drying process to optical fiber；Due to fibre-optical probe can not high-temperature process, use
50 DEG C of temperature and low humidity handle within 10 minutes to optical fiber, then uses deionized water, washes of absolute alcohol fiber end face；
(3) plated film: the optical fiber head after cleaning being put into wet-sensitive liquid to apply back and forth and is drawn, and is uniformly adhered on guarantee optical fiber head as far as possible
Upper wet-sensitive liquid；
(4) dry: the optical fiber after immersion to be placed into 50 degree of insulating box, heated 24 hours, the light after obtaining plated film
Fibre probe, is placed in the environment of hermetically drying.
Further, the humidity sensing layer 2 is lithium chloride-polyvinyl alcohol humidity sensitive thin film.
Further, the light source 7 is laser semiconductor light source.
Further, first light power meter 8 and the second light power meter 9 are designed with power digital display device.
Further, first light power meter 8 and the second light power meter 9 are designed with RS-232 interface.
As shown in Fig. 2, a kind of optical fiber dewpoint humidity detection system includes: optical fiber dewpoint humidity detection dress as described above
It sets, computing controller 10, data collector 11, temperature sensor 12, refrigerator 13 and actuator 14；Computing controller 10 is distinguished
It is attached with data collector 11, the first light power meter 8, the second light power meter 9；Actuator 14 respectively with data collector
11, refrigerator 13 is electrically connected；One end of first optical fiber 1 or set on refrigerator 13 formed refrigeration space in；
The computing controller 10 exports corresponding control instruction for reading, handling and analysis detecting data；
The data collector 11 is used to read the detection data of temperature sensor 12, and according to the finger of computing controller 10
Enable control actuator 14；
The temperature sensor 12 is used to detect the environment temperature of the refrigeration space of the formation of refrigerator 13, and will test data
Send data collector 11 to；
The refrigerator 13 is used to carry out refrigeration cool-down to the refrigeration space for being equipped with the first optical fiber 1；
The actuator 14 is for controlling the start and stop of refrigerator 13 and/or operating power.
Specifically, the temperature sensor 12 selects MCT80S slimline temperature transmitter, 24VCD is used to power,
PT100 input, export 4~20mA, 0~30 DEG C of range, temperature drift < ± 0.025% DEG C, have precision is high, anti-interference, stability is good
The advantages that；
The working principle of temperature sensor 12: it is affected by temperature and generates resistance or potential effect, one electricity of converted generation
Signal is pressed, this signal sends out 4-20mA current signal corresponding with range or 0-5V, 0-10V voltage after instrument amplifier is amplified
Signal.
Specifically, the refrigerator 13 selects XH-X266 type semiconductor refrigerating module, control heating cooling uses 1 road 5v
Relay module is attached thereto by data collector；The semiconductor refrigerating module does not need special working environment, to environment
Pollution-free, cooling parameters can be adjusted at will, in addition can also be by changing sense of current, to change the operation of refrigerator 13
State.
Specifically, the actuator uses 1 road 5v relay module, it is attached thereto by data collector 11, Ke Yizhi
The operation and pause for controlling refrigerator 13 at any time on software are connect, is not only facilitated but also safe；The module interface mode are as follows: DC+
Positive pole is connect, DC- connects power cathode, and IN can control relay with high or low level and be attracted；Its output end are as follows: NO is relay
Normally opened interface, relay is hanging before being attracted, and is shorted after actuation with COM；COM is then relay common interface；NC is that relay is normal
Interface is closed, relay is shorted before being attracted with COM, hanging after actuation.
Specifically, data collector 11 uses PCI-6221 data collecting card, it is mainly logical using AI and AO in an experiment
Road, VI program realize the collection of simulant signal and output function of virtual instrument by it；PCI-6221 data collecting card is base
High-performance, multi-functional data collecting card in pci bus；Its basic specification are as follows: 16 tunnel simulation inputs, 16 bit resolutions；
250kS/s sampling rate；8 Differential Inputs, 1 16 successive approximations ADC, 2 16 DAC with voltage output；24
Railway digital I/O；The maximum voltage that the channel AI, AO can be born is ± 10v；Temperature sensor 12 at electric signal, leads to temperature transition
It crosses PCI-6221 data collecting card it is passed to computing controller 10 and be processed into required data by LabVIEW software systems.
Further, the computing controller 10 distinguishes the first light power meter 8, the second smooth function by RS-232 communication protocol
Rate meter 9 is attached.
As shown in Figure 2 and Figure 3, computing controller 10 is equipped with a calculation control module；The calculation control module includes light
Power meter setup module 15, carrying out shake communication module 16, temperature collecting module 17, dew point judgment module 18, refractive index computing module
19, data save template 20 and virtual display module 21；
The light power meter setup module 15 is used to send parameter to the first light power meter 8 and/or the second light power meter 9 and set
Order and/or reading order are set, and reads the response cue of the first light power meter 8 and/or the second light power meter 9；
The carrying out shake communication module 16 is used to detect the connection status of the first light power meter 8 and/or the second light power meter 9；
The temperature collecting module 17 is used for the real time temperature data of temperature collection sensor 12；
The dew point judgment module 18 according to the real time temperature data of temperature collecting module 17 for calculating and judging to make
The dew point for the refrigeration space that cooler 13 is formed forms moment and temperature value；
The refractive index computing module 19 is used for the function according to the magnitude of power of the first light power meter 8, the second light power meter 9
The index meter of rate score, the refractive index of air and fiber core calculates the refractive index of humidity sensing layer 2；
The data save template 20 for protecting to temperature collecting module 17 and the data of refractive index computing module 19
It deposits；
The virtual display module 21 is used to virtually show control process, the data variation process of the computing controller 10
And parameter setting procedure.
Specifically, the workflow of carrying out shake communication module 16 be when computing controller 10 send "? " when, if shaken hands into
Function, the first light power meter 8 and/or the second light power meter 9 should respond " ".But when CPU has task processing (only returning to zero
Just have such case when operation, at this moment will not respond any order), then it can respond " B ".If response when be not this two
Kind signal has the case where delay (response time is in the ms order of magnitude), indicates connection or problematic (the connection error of light power meter
Or systemic breakdown).
Specifically, the temperature acquisition program of temperature collecting module 12 includes the sub- vi of temperature conversion, the setting of temperature bound, temperature
Degree meter, the sub- vi of humidity and dew-point temperature and humidity display；Temperature bound is set as 0~30 DEG C, and report can be shown by going beyond the scope
It is alert；The situation of change of thermometer then Dynamically Announce temperature, minimum scale are 0.1 DEG C, can be used to read general real time temperature；
Program brings into operation the temperature value read after (refrigeration also inactive) 2s as room temperature, is then turned on refrigeration and is tested, works as folding
When penetrating rate curve apparent inflection point (the sporting decline by rising) of appearance, actuator 14 can control refrigerator, its is made to stop cooling,
The real-time temperature values that temperature collecting module 17 is read at this time are dew-point temperature；Room temperature, dew-point temperature numerical value pass through hygrometer
Operator vi can obtain corresponding humidity value.
Specifically, as shown in figs. 3 and 5, the specific course of work of dew point judgment module 18 is the dew automatically controlled under situation
Point judges sub- vi, and program is divided into one group the refractive index value read every 3 and finds out its average value, then again by adjacent 3
A average value compares, and judgement is rising or downward trend, when maximum value is when intermediate (i.e. index is 1) in 3 numbers, just
Illustrate there is the case where mutation, when three numbers are first increases and then decreases, can determine whether that refractive index reaches maximum value, program will at this time
Refrigerator 13, which is controlled, by actuator 14 takes stopping refrigeration mode；When three numbers are first to reduce to increase afterwards, can determine whether to reflect
Rate reaches minimum value, and correspondingly system can open refrigeration；When periodically response occurs in refractive index (such as Fig. 9 institute in experimentation
Show), system will periodically cool down-heat up, and corresponding temperature curve is also in cyclically-varying.
Specifically, as shown in Fig. 3, Fig. 6, the specific course of work of refractive index computing module 19 is obtains institute by correction program
After the C value needed, folding to be measured can be calculated in conjunction with the refractive index of two magnitude of powers, the refractive index of air and fiber core
Penetrate rate size；The program chart of Fig. 6 is obtained by twin-channel Fresnel reflection principle, is derived by theoretical formula, is then passed through
Deformation replacement write-in program；This method greatly reduces the difficulty of calculating, and the speed of service is fast.
Specifically, data save the program that template 20 executes such as Fig. 7, and the program will be for that will collect as shown in Fig. 3, Fig. 7
Refractive index and temperature data document is written by file I/O, facilitate further analysis to handle, wherein refractive index setting data essence
Degree is five after decimal point.
Specifically, the interface that virtual display module 21 is virtually shown includes two large divisions's group as shown in Fig. 3, Fig. 8
At being refractive index acquisition system and temperature acquisition system respectively, wherein refractive index acquisition system includes channel data display field, school
Positive action bar, process control column, data save column etc.；Laboratory ensures that the serial port setting in two channels is correct, specifically needs basis
Depending on the equipment connection in laboratory, first passage is the light power meter that the probe being placed in air is connected, and second channel is to survey
The connected light power meter of amount probe；Before experiment, the first optical fiber 1 and the second optical fiber 3 are all placed in air, then click correction
Button carries out the correction of constant C；In addition setting is needed to save the path of experimental data, to prevent loss of data；The temperature acquisition at interface
Acquisition system mainly includes the setting of physical channel, and the data such as real time temperature, room temperature, dew-point temperature, humidity show control, and
Thermometer, refrigeration control button, alarm indication.
Further, as shown in Fig. 2, the computing controller 10 is also equipped with a LabVIEW software systems.
Specifically, LabVIEW software systems are developed using LabVIEW8.6；The design philosophy of system software is from number
It is read in the channel specified according to collector and is stored and shown on panel after data perform corresponding processing, while generating control
Signal processed is sent into output channel.
As shown in figure 4, a kind of control method of optical fiber dewpoint humidity detection system is applied to optical fiber dew point as described above
Dust humidity detection system, the control method the following steps are included:
S1, computing controller 10 cool down to the refrigeration space for being equipped with the first optical fiber 1 by control refrigerator 13；
S2, the first light power meter 8 acquire the real time data of the refractive index of the first optical fiber 1；Second light power meter 9 acquisition second
The real time data of the refractive index of optical fiber 3；The real time data of 12 temperature collection of temperature sensor；
S3, the first light power meter 8, the second light power meter 9, temperature sensor 12 will acquire data and be passed to computing controller
10；
S4, computing controller 10 carry out temperature control to refrigerator 13, and by being installed in computing controller 10
LabVIEW software systems handle to obtain refractive index-time graph and temperature-time curve；
S5, computing controller 10 are judged by analytical refraction rate-time graph knee of curve equipped with the first optical fiber 1
The temperature value of the appearance condensation of refrigeration space；
S6, computing controller 10 handle the data of temperature collecting module 17, it is made to be transformed into corresponding temperature folding
Simultaneously corresponding relative humidity at room temperature is calculated in radiance rate value.
Specifically, as temperature reduces, the refractive index of humidity sensing layer 2 is increasing in S6；When temperature drops to certain value
When, there is inflection point in refractive index-time graph, at this time it is believed that having reached the temperature of the sub- condensation of Environmental Water, humidity sensitive thin film by
In thering is dew to be formed and dissolving in, refractive index is caused to decline；System automatically obtains temperature at this time and stops freezing when inflection point, and temperature is again
It is gradually increasing, therefore, refractive index-time graph highest point corresponding temperature-time graph minimum point, system can be read automatically
Inflection temperature is simultaneously converted into relative humidity and shows；It selects humidity environments different to be three times acquired, is tied as shown in table 1 below
Fruit；From table 1 it follows that institute's measuring moisture data and hygrometer institute measured data meet it is preferable, it was demonstrated that the reliability of method；
Its error is mainly derived from the error in judgement of dew-point temperature, response error of the refractive index curve for dew point；
Table 1 compares for system institute measuring moisture with hygrometer:
| Room temperature | Dew-point temperature | This paper institute measuring moisture | Hygrometer institute measuring moisture | |
| 1 | 29.8℃ | 6.0℃ | 22.6% | 23% |
| 2 | 24.5℃ | 11.2℃ | 43.7% | 43% |
| 3 | 27.4℃ | 24.2℃ | 83.6% | 84% |
Table 1
Specifically, as shown in figure 9, precisely being corrected in S6 using the method for repeated experiment；
Influence of the cyclical upturn and downturn temperature to measurement result is tested, as a result as shown in Figure 9；Due to polyvinyl alcohol-lithium chloride
Humidity absorption and release effect it is fine, therefore when changing Temperature cyclingly, leading to refractive index, also correspondingly generating period changes,
Experiments have shown that the wet sensitive of the film works well, system also has the advantage of repetition measurement.It can continuously be adopted when reality measurement
It is averaged after collection is multiple, the humidity result finally measured in this way is more accurate.
(operation evolution process such as Figure 10, Figure 11 is further explained in the working principle of the invention combination calculation formula
With shown in Figure 12):
Wherein nx is refractive index to be measured, and nc is fiber core refractive index, and n0 is air refraction, and R is optical fiber head 1 and optical fiber
First 2 beam intensity ratio (optical fiber head 1 is put into environment to be measured, and 2 are placed in air)；When K is that two optical fiber heads are all put in air, optical fiber
First 1 and 2 beam intensity ratio；
The definition of relative humidity (RH%): at the same temperature the actual water vapor pressure (being expressed as Pn) of unit volume air and
The percentage of saturation vapour pressure (being expressed as Pw).Expression formula are as follows:
Simplified saturation vapour pressure equation is as follows:
Wherein t is environment temperature, temperature range: -45 DEG C~+60 DEG C；
Wherein td is dew-point temperature, temperature range: -65 DEG C~+0.01 DEG C；
The calculation formula that relative humidity can be obtained in simultaneous is
The program form figure of the formula is Figure 12.
Working principle of the present invention is as follows:
Hardware system of the invention is understood that be passed by refrigeration system, signal acquiring system, optical fiber sensing system, temperature
Sensing system and master system composition, optical fiber sensing system are used to monitor the variations in refractive index in temperature-fall period, temperature sensing system
System is for monitoring temperature change.When temperature drops to dew point, there is inflection point in refractive index-time graph, can be obtained by temperature-time curve
The temperature, thus ambient humidity can be obtained.Software systems use LABVIEW software platform, by with optical fiber sensing system
Communication collects data, and in virtual oscillograph interface display, dynamic observation experiment data can show process in real time.
Virtual instrument applies the functional module of completely new system monitoring and control equipment and combination of hardware, and user can pass through friendly
The computer that pattern manipulation interface is shown completes the entirely test work such as acquisition, analysis, processing, display, storage of measurement data
Make, and remotely monitor and data sharing by network implementations, being sensed using optical fibre refractivity relatively accurately to be measured in environment
The humidity of gas.
Present invention combination LabVIEW software platform and corresponding hardware realize the survey to temperature refraction rate and humidity
Amount, display and control；When system measures, by the first optical fiber head of coated lithium chloride-polyvinyl alcohol humidity sensitive thin film and temperature
Sensor probe is spent close to the chill surface of refrigerator, is started refrigerator and is started to cool down, starts simultaneously at the folding of acquisition hygrometric sensitive film
The rate of penetrating-time data and Temperature-time data, signal are sent into computing controller by serial ports and data collecting card and (be can be
Bit machine), refractive index-time graph and temperature-time curve are obtained after being handled by LabVIEW software platform and are shown in void
Quasi- panel.When temperature drops to dew point, there is inflection point in refractive index-time graph, and software, which judges automatically the temperature at inflection point, (can recognize
It is dew-point temperature for the temperature), program is calculated corresponding relative humidity at room temperature and shows；Hardware components roll over temperature
The rate signal of penetrating is converted into electric signal, and carries out conditioning conversion, data is passed to computing controller, while according to the finger of functional software
Order controls temperature；Software section is responsible for handling the data inputted from data collector, is transformed into it accordingly
Temperature refraction rate value and corresponding relative humidity at room temperature is calculated, then in the corresponding display of virtual display module
It is upper to show corresponding figure line and data, and it is stored in hard disk, while receiving the desired temperature of user's input, generate control signal；
Whole measurement process of system carry out under the control of mouse or keyboard in the virtual panel of computing controller.This structure
Hardware design is not only simplified, is reduced costs, and provides advantage for the later improvement of test macro, makes user to instrument
Operation become more simple and fast.
The function of system can divide are as follows:
(1) temperature measurement and display.Continuous voltage signal is converted by environment temperature by temperature sensor, after conditioning
A/D conversion is carried out by data collector afterwards, and data are sent into computer, instrumental function software is transferred to handle and are shown.
(2) refractometry and display.
(3) refrigeration system.The operation and pause of refrigerator can be controlled at any time directly on software, not only facilitate but also pacified
Entirely.
(4) humidity is calculated and is shown.According to the relationship between dew-point temperature and relative humidity, calculated by program by dew point
Temperature obtains relative humidity at room temperature and is shown in virtual panel.
(5) data store.It will store by the data of the Temperature and Humidity module of software processing into a specified electronic form file
For later analysis and teleengineering support.
The embodiments described above only express several embodiments of the present invention, and the description thereof is more specific and detailed, but simultaneously
Limitations on the scope of the patent of the present invention therefore cannot be interpreted as.It should be pointed out that for those of ordinary skill in the art
For, without departing from the inventive concept of the premise, various modifications and improvements can be made, these belong to guarantor of the invention
Protect range.Therefore, the scope of protection of the patent of the invention shall be subject to the appended claims.
Claims (10)
1. a kind of optical fiber dewpoint humidity detection device characterized by comprising the first optical fiber (1), humidity sensing layer (2), the second optical fiber
(3), the first fiber coupler (4), the second fiber coupler (5), third fiber coupler (6), light source (7), the first optical power
Count (8) and the second light power meter (9)；
One end of first optical fiber (1) is coated with humidity sensing layer (2), and is set to interior in the environment space for carrying out temperature adjusting；The
The other end of one optical fiber (1) and one end of the first fiber coupler (4) carry out guide-lighting connection；First fiber coupler (4) it is another
One end of one end and third fiber coupler (6) carries out guide-lighting connection；
One end of second optical fiber (3) is set in the environment space of the not formed dew point of air；The other end of second optical fiber (3) with
One end of second fiber coupler (5) carries out guide-lighting connection；The other end and third fiber coupler of second fiber coupler (5)
(6) one end carries out guide-lighting connection；
The other end of the third fiber coupler (6) and light source (7) carry out guide-lighting connection；First light power meter (8) and first
Fiber coupler (4) carries out guide-lighting connection；Second light power meter (9) and the second fiber coupler (5) carry out guide-lighting connection；
First optical fiber (1) is used to detect the humidity for the Experimental Area that air forms dew point；
The humidity sensing layer (2) is used to absorb the air moisture of the Experimental Area, and changes the refractive index of the first optical fiber (1)；
Second optical fiber (3) is used to detect the humidity of the environment of the not formed dew point of air；
Light splitting connector of first fiber coupler (4) as the first optical fiber (1) and the first light power meter (8)；Described
Light splitting connector of two fiber couplers (5) as the second optical fiber (3) and the second light power meter (9)；The third fiber coupling
Device (6) is as the first fiber coupler (4), the light splitting connector of the second fiber coupler (5) and light source (7)；
The light source (7) is used for while providing the light of same luminance to the first optical fiber (1) and the second optical fiber (3)；
First light power meter (8) is used to acquire the real time data of the refractive index of the first optical fiber (1)；
Second light power meter (9) is used to acquire the real time data of the refractive index of the second optical fiber (3).
2. optical fiber dewpoint humidity detection device according to claim 1, which is characterized in that the humidity sensing layer (2) is chlorination
Lithium-polyvinyl alcohol humidity sensitive thin film.
3. optical fiber dewpoint humidity detection device according to claim 1, which is characterized in that the light source (7) is laser half
Conductor light source.
4. optical fiber dewpoint humidity detection device according to claim 1, which is characterized in that first light power meter (8)
Power digital display device is designed with the second light power meter (9).
5. optical fiber dewpoint humidity detection device according to claim 1, which is characterized in that first light power meter (8)
RS-232 interface is designed with the second light power meter (9).
6. a kind of optical fiber dewpoint humidity detection system characterized by comprising the optical fiber dew as described in claim 1-6 is any
Point humidity detector, computing controller (10), data collector (11), temperature sensor (12), refrigerator (13) and execution
Device (14)；Computing controller (10) is carried out with data collector (11), the first light power meter (8), the second light power meter (9) respectively
Connection；Actuator (14) is electrically connected with data collector (11), refrigerator (13) respectively；First optical fiber (1)
One end is set in the refrigeration space that refrigerator (13) are formed；
The computing controller (10) exports corresponding control instruction for reading, handling and analysis detecting data；
The data collector (11) is used to read the detection data of temperature sensor (12), and according to computing controller (10)
Instruction control actuator (14)；
The temperature sensor (12) is used to detect the environment temperature of the refrigeration space of refrigerator (13) formation, and will test data
Send data collector (11) to；
The refrigerator (13) is used to carry out refrigeration cool-down to the refrigeration space for being equipped with the first optical fiber (1)；
The actuator (14) is for controlling the start and stop of refrigerator (13) and/or operating power.
7. optical fiber dewpoint humidity detection system according to claim 6, which is characterized in that the computing controller (10) is logical
Cross RS-232 communication protocol difference the first light power meter (8), the second light power meter (9) is attached.
8. optical fiber dewpoint humidity detection system according to claim 6, which is characterized in that computing controller (10) is equipped with
One calculation control module；The calculation control module includes light power meter setup module (15), carrying out shake communication module (16), temperature
Acquisition module (17), dew point judgment module (18), refractive index computing module (19), data save template (20) and virtual display mould
Block (21)；
The light power meter setup module (15) is used to send parameter to the first light power meter (8) and/or the second light power meter (9)
Setting command and/or reading order, and read the response contact letter of the first light power meter (8) and/or the second light power meter (9)
Number；
The carrying out shake communication module (16) is used to detect the connection shape of the first light power meter (8) and/or the second light power meter (9)
State；
The temperature collecting module (17) is used for the real time temperature data of temperature collection sensor (12)；
The dew point judgment module (18) according to the real time temperature data of temperature collecting module (17) for calculating and judging to make
The dew point for the refrigeration space that cooler (13) is formed forms moment and temperature value；
The refractive index computing module (19) is used for according to the magnitude of powers of the first light power meter (8), the second light power meter (9)
The index meter of magnitude of power, the refractive index of air and fiber core calculates the refractive index of humidity sensing layer (2)；
The data save template (20) and are used to carry out the data of temperature collecting module (17) and refractive index computing module (19)
It saves；
The virtual display module (21) is used to virtually show control process, the data variation process of the computing controller (10)
And parameter setting procedure.
9. optical fiber dewpoint humidity detection system according to claim 6, which is characterized in that computing controller (10) is also installed
There are a LabVIEW software systems.
10. a kind of control method of optical fiber dewpoint humidity detection system, which is characterized in that the control method is applied to want such as right
Optical fiber dewpoint humidity detection system described in asking 9, the control method the following steps are included:
S1, computing controller (10) cool down to the refrigeration space for being equipped with the first optical fiber (1) by control refrigerator (13)；
S2, the first light power meter (8) acquire the real time data of the refractive index of the first optical fiber (1)；Second light power meter (9) acquisition the
The real time data of the refractive index of two optical fiber (3)；The real time data of temperature sensor (12) temperature collection；
S3, the first light power meter (8), the second light power meter (9), temperature sensor (12) will acquire data and be passed to computing controller
(10)；
S4, computing controller (10) carry out temperature control to refrigerator (13), and by being installed in computing controller (10)
LabVIEW software systems handle to obtain refractive index-time graph and temperature-time curve；
S5, computing controller (10) are judged by analytical refraction rate-time graph knee of curve equipped with the first optical fiber (1)
The temperature value of the appearance condensation of refrigeration space；
S6, computing controller (10) handle the data of temperature collecting module (17), it is made to be transformed into corresponding temperature folding
Simultaneously corresponding relative humidity at room temperature is calculated in radiance rate value.
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| CN113029967A (en) * | 2021-03-25 | 2021-06-25 | 广东工业大学 | Device and method for measuring air humidity |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE4122619A1 (en) * | 1991-07-09 | 1993-01-14 | Oberspree Habelwerk Gmbh | Fibre-optic sensor for detecting liquids and moist gases - comprising silica core, with fluoride glass cladding of lower refractive index |
| CN1329719A (en) * | 1998-10-30 | 2002-01-02 | 奥普蒂盖德有限公司 | Dew point hygrometers and dew sensors |
| CN101109664A (en) * | 2007-08-21 | 2008-01-23 | 李亚滨 | Optical fiber temp/moisture sensor and manufacturing method and metering installation thereof |
| JP4597251B1 (en) * | 2009-05-22 | 2010-12-15 | ファイバーラボ株式会社 | Optical fiber sensor device and sensing method using optical fiber |
| CN102183488A (en) * | 2011-03-04 | 2011-09-14 | 北京交通大学 | Refractive index sensor based on blazed long-period fibre grating |
| CN202599939U (en) * | 2012-06-26 | 2012-12-12 | 重庆市电力公司江津供电局 | Humidity detection device based on refrigerating technology |
| CN203894159U (en) * | 2014-04-11 | 2014-10-22 | 中国计量学院 | Relative humidity monitoring system based on long-period fiber grating |
-
2018
- 2018-07-20 CN CN201810801296.5A patent/CN109239011A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE4122619A1 (en) * | 1991-07-09 | 1993-01-14 | Oberspree Habelwerk Gmbh | Fibre-optic sensor for detecting liquids and moist gases - comprising silica core, with fluoride glass cladding of lower refractive index |
| CN1329719A (en) * | 1998-10-30 | 2002-01-02 | 奥普蒂盖德有限公司 | Dew point hygrometers and dew sensors |
| CN101109664A (en) * | 2007-08-21 | 2008-01-23 | 李亚滨 | Optical fiber temp/moisture sensor and manufacturing method and metering installation thereof |
| JP4597251B1 (en) * | 2009-05-22 | 2010-12-15 | ファイバーラボ株式会社 | Optical fiber sensor device and sensing method using optical fiber |
| CN102183488A (en) * | 2011-03-04 | 2011-09-14 | 北京交通大学 | Refractive index sensor based on blazed long-period fibre grating |
| CN202599939U (en) * | 2012-06-26 | 2012-12-12 | 重庆市电力公司江津供电局 | Humidity detection device based on refrigerating technology |
| CN203894159U (en) * | 2014-04-11 | 2014-10-22 | 中国计量学院 | Relative humidity monitoring system based on long-period fiber grating |
Non-Patent Citations (4)
| Title |
|---|
| MASANABU MATSUGUCHI ET AL.: "Improvements in the long-term stability of a LiCl dew-point sensor using cross-linked porous poly(vinyl alcohol) film", 《SENSORS AND ACTUATORS B》, vol. 97, pages 74 - 80, XP004483098, DOI: 10.1016/j.snb.2003.07.007 * |
| T.L.YEO ET AL.: "Characterisation of a polymer-coated fibre Bragg grating sensor for relative humidity sensing", 《SENSORS AND ACTUATORS B》, vol. 110, pages 148 - 155 * |
| 黄振健;谭春华;黄旭光;: "基于光纤折射率传感原理的新颖酸碱滴定法", 化学学报, no. 11 * |
| 黄振健;谭春华;黄旭光;: "基于光纤折射率传感原理的表面活性剂临界胶束浓度测定方法", 物理化学学报, no. 05, pages 1271 - 1276 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113029967A (en) * | 2021-03-25 | 2021-06-25 | 广东工业大学 | Device and method for measuring air humidity |
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