CN111122499B - Radial plume multi-component gas measurement remote sensing system - Google Patents
Radial plume multi-component gas measurement remote sensing system Download PDFInfo
- Publication number
- CN111122499B CN111122499B CN201911380938.XA CN201911380938A CN111122499B CN 111122499 B CN111122499 B CN 111122499B CN 201911380938 A CN201911380938 A CN 201911380938A CN 111122499 B CN111122499 B CN 111122499B
- Authority
- CN
- China
- Prior art keywords
- laser
- gas
- detector
- data acquisition
- lens
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- 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
- G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
- G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
- G01N21/39—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using tunable lasers
Landscapes
- Physics & Mathematics (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Analytical Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Optics & Photonics (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
Abstract
The invention relates to a radial plume multi-component gas measurement remote sensing system, which belongs to the field of laser remote sensing measurement and comprises a reflection laser acquisition unit and a data acquisition unit; the data acquisition unit includes data acquisition card and computer, reflection laser acquisition unit includes a plurality of lasers, the light of every laser is divided into two the tunnel through the beam splitter, shine to first detector through reference absorption cell all the way, another way light all shines to the beam expander through beam combiner, cooperation target reflector has set gradually along the light path, the speculum, first lens, and assemble to the grating, realize the separation of different wavelengths in grating department, the light of different wavelengths incides to the second detector that is connected with the data acquisition card through narrowband filter and second lens, the laser quantity is more than two, the laser is the semiconductor laser that can modulate, scanning frequency is greater than 100Hz, modulation frequency is greater than 20 kHz. The invention has simple and compact structure and high sensitivity, and can detect the concentration of various gases in the air in real time.
Description
Technical Field
The invention relates to a radial plume multi-component gas measurement remote sensing system, and belongs to the technical field of laser remote sensing measurement.
Background
Many chemical industrial parks are exposed to toxic and harmful gases such as H2S、CH4、NH3And CO causes serious pollution to the residential air environment of surrounding people and personal safety to workers in a chemical industry park. The method has important significance for monitoring the toxic gases in real time and monitoring the spatial distribution moving characteristics. At present, a multi-component gas measurement system adopts a mass spectrum technology and an open-circuit Fourier spectrum technology.
At present, the mass spectrometry technology needs sample sampling and sample processing, consumes long time and cannot carry out real-time and regional measurement. The light source adopted by the traditional open-circuit Fourier spectrometer is an incoherent light source, the detection distance is short, the measurement sensitivity is low, the equipment and instruments are complex, and regional gas scanning cannot be carried out. And the laser remote sensing type measuring system can realize remote gas measurement. Aiming at the absorption peak of a special target gas, a plurality of small lasers can be integrated to realize the measurement of a plurality of gas components, and the moving distribution characteristic of the concentration of multi-component gas in a three-dimensional region is realized according to different cooperative targets in a setting region, so that a radial plume multi-component gas measurement system is realized, and related patents and reports are not found at present.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides a radial plume multi-component gas measurement remote sensing system which is simple and compact in structure, high in sensitivity and capable of detecting the concentration of various gases (such as toxic gases) in the air in real time.
Interpretation of terms:
radial plume: refers to the gas along the laser measurement direction that is distinguished from the surrounding gaseous medium by gas leakage or venting.
The invention adopts the following technical scheme:
a radial plume multi-component gas measurement remote sensing system comprises a reflection laser acquisition unit and a data acquisition unit;
the data acquisition unit comprises a data acquisition card and a computer which are connected with each other, the data acquisition card can realize the functions of data acquisition, A/D conversion and the like, and transmits the acquired photoelectric signals to the computer to realize calculation and analysis in the computer, the computer is preferably a portable computer, the reflection laser acquisition unit comprises a plurality of lasers connected with the data acquisition card, the light of each laser is divided into two paths by a beam splitter, one path of light irradiates to a first detector through a reference absorption cell, the first detector is connected with the data acquisition card, the other path of light irradiates to a beam expander through a beam combiner, the beam expander realizes beam expansion and collimation of the laser, so that the output laser has a small divergence angle, a cooperative target reflector, a reflector and a first lens are sequentially arranged along the light path direction of the beam expander, and the light is converged to a grating through the first lens, the separation of different wavelengths is realized at the grating, the light of different wavelengths is incident on a second detector through a narrow-band filter and a second lens, and the second detector is connected with a data acquisition card;
the data acquisition card of the invention is combined with a computer, and has the functions of generating scanning signals of a semiconductor laser, generating modulation signals, demodulating digital software, calculating Kalman filtering algorithm and the like.
The laser, the beam splitter, the reference absorption cell, the first detector, the narrow-band filter, the second lens and the second detector are corresponding in number, and the number of the laser, the beam splitter, the reference absorption cell, the first detector, the narrow-band filter, the second lens and the second detector is more than two;
the laser is a modulatable semiconductor laser, the modulatable semiconductor laser is a semiconductor laser device which can adjust the wavelength and the laser power through current, and has the characteristics of tunability and compact system, the scanning frequency of the modulatable semiconductor laser is more than 100Hz, and the modulation frequency is more than 20kHz, so that the laser is used for inhibiting the influence of atmospheric turbulence.
The radial plume multi-component gas measurement remote sensing system can realize remote detection according to the number of the lasers, can realize detection of the distance above 1km at most, can appropriately increase or decrease the number of the lasers according to the types and the contents of gases in the atmosphere, and correspondingly increases or decreases the number of the beam splitter, the reference absorption cell, the first detector, the narrow-band filter, the second lens and the second detector.
Preferably, a vertical scanning mirror is further arranged between the beam expander and the cooperative target reflecting mirror, and a light beam irradiates to the cooperative target reflecting mirror through the vertical scanning mirror along the beam expander, then irradiates to the reflecting mirror through the vertical scanning mirror, and is converged to a grating through a first lens;
the system comprises a plurality of lasers, a beam splitter, a reference absorption cell, a first detector, a beam combiner, a beam expander, a vertical scanning mirror, a reflecting mirror, a first lens, a grating, a narrow-band filter, a second lens and a second detector which are respectively connected with the plurality of lasers, wherein the beam splitter, the reference absorption cell, the first detector, the beam combiner, the beam expander, the vertical scanning mirror, the reflecting mirror, the first lens, the grating, the narrow-band filter, the second lens and the second detector are integrated into a whole structure and are arranged on a horizontal rotating platform to realize gas concentration measurement in a horizontal plane;
the number of the cooperative target reflecting mirrors is multiple, and the cooperative target reflecting mirrors are arranged in a certain horizontal plane to be measured and a certain vertical plane to be measured.
Preferably, the vertical scanning mirror may be a scanning galvanometer or a rotating prism, and is configured to irradiate a horizontal light beam to a cooperative target reflecting mirror above or below a remote location, and then irradiate the light beam onto the reflecting mirror through the vertical scanning mirror, so that gas concentration measurement is achieved when the cooperative target reflecting mirror is vertically distributed, and the scanning galvanometer and the rotating prism are both the prior art and are not described herein again.
Preferably, the preferred range of the laser wavelength is 1500-2000nm, the selected laser wavelength can cover target gas molecular spectrum such as methane, ammonia molecules and the like, and the laser power is preferably more than 10 mW;
the first detector and the second detector are both InGaAs APD detectors, the first detector and the second detector are used for receiving high sensitivity to achieve collection of weak optical signals of backscatter detection signals, and more than two kinds of gas can adopt InGaAs APD arrays.
Preferably, the laser is a butterfly laser, a quantum cascade laser, an interband cascade laser, or the like.
Preferably, the diameter of the cooperative target reflector is 30-60mm, the distance between the cooperative target reflector and the laser is more than 1000m, and the method is suitable for measuring the gas concentration between the emission position of the laser and the cooperative target reflector and realizing the regional gas measurement.
Preferably, the reference absorption cell contains a high-concentration reference gas, and the concentration of the reference gas is greater than or equal to 1%.
Preferably, the two ends inside the reference absorption cell are optical fiber ports, or the reference absorption cell is provided with a glass window.
Preferably, the data acquisition card is NI-6531 of NI company, the data acquisition card has 8 channels, 16 channels and the like, the measurement speed is 3MHZ, and the interface form is a USB interface.
Preferably, the grating is a blazed grating, the size of the blazed grating is preferably 25mm × 25mm, the angle of the blazed grating is 25-30 degrees, the angle of the blazed grating is an included angle between a grating surface structure and a surface parallel line, and belongs to the technical term, and the grating stripe is preferably 500-; the grating is used for realizing two-way or multi-way light spot separation.
Preferably, the blazed grating angle is 28 degrees and the grating stripes are 600/mm.
Further preferably, the central wavelength of the narrow-band filter is adapted to the central wavelength of the absorption peak of the gas to be measured, the bandwidth of the narrow-band filter is 1.5nm, the narrow-band interference filter can suppress stray light except laser wavelength and output back echo signals, and the narrow-band filter is matched with the convex lens and used for realizing light spot convergence.
Further preferably, the beam expansion multiple of the beam expander is 10 times, and the divergence angle of the laser can be compressed to 0.1mrad, so that a good result of the remote sensing system can be obtained.
The system of the invention takes laser spectrum absorption As a principle, adopts a digital wavelength modulation spectrum technology, adopts a corresponding tunable semiconductor laser, an In-Ga-As APD detector, a reference absorption cell and a modulation and demodulation software core component realized based on digital software to realize a multi-component gas measuring device, adopts a second harmonic and first harmonic ratio method and a Kalman filtering algorithm to obtain a compact gas measuring device with high sensitivity and simple structure In real time, and is mainly used for remotely sensing and detecting parameters such As gas concentration In real time.
The working principle of the radial plume multi-component gas measurement remote sensing system is as follows:
taking an example of arranging a laser, two paths of scanning and modulating signals are generated by using a data acquisition card, each path of scanning and modulating signal is used for driving the current of the modulating laser to realize the modulation of the output wavelength of the laser, the signals are respectively a first harmonic wave and a second harmonic wave, the output lasers of the two paths of lasers are respectively divided into two paths by a beam splitter, wherein the two paths of lasers with weaker energy pass through a reference absorption cell filled with reference gas and are subjected to photoelectric conversion by a first detector, and S is used for converting the output laser energy into S11r、S12rRespectively representing the first harmonic signal amplitude value and the second harmonic signal amplitude value of a reference absorption cell, combining two paths of lasers with stronger energy (the energy ratio of the stronger energy to the weaker energy is preferably 99:1), and then performing beam expansion collimationAfter the transmission distance in the open circuit space is more than 1km, the optical fiber is reflected by a cooperative target reflector, the separation of different wavelengths is realized on a grating after the reflection mirror and a first lens are converged, and photoelectric conversion is realized on a second detector through the convergence of a narrow-band filter and a second lens to S11、S12Respectively representing the first harmonic signal amplitude value and the second harmonic signal amplitude value of the remote sensing measurement with stronger energy, and knowing the distance L between the cooperative target reflector and the laser2Length L of reference absorption cell1And other concentration information C in the reference absorption tank1Obtaining the open-circuit measurement gas concentration as follows:
UC1＝(S12r*S11)*L1*C1/(S12*S11r*L2) (1)
the acquired concentration information UC1 may be subjected to noise filtering, and the noise filtering algorithm preferably selects a kalman filtering algorithm for use in the data processing inside the computer software, where the kalman filtering algorithm is selected to filter noise in real time, reduce interference of other noise, and acquire high-sensitivity concentration information.
The kalman filtering algorithm is prior art, and can be performed with reference to the following:
a. setting a concentration value of gas in the atmosphere at normal temperature, a system measurement error and a process error caused by environmental change;
b. the remote sensing system of the invention obtains the measured concentration information in real time;
c. performing state prediction calculation and covariance prediction calculation according to the measured concentration information, calculating Kalman filtering gain, and updating the state and covariance;
d. through multiple recursion calculations, the state prediction calculates the final result.
The system is provided with a plurality of lasers, the light path principle and the calculation formula corresponding to each laser are the same as those of one laser, measurement and calculation can be performed in sequence, and details are not repeated here.
The reference absorption cell used by the invention can be used for correcting two-bit variation of modulated laser in atmospheric transmissionThe specific principle is as follows: the phase information of the reference absorption cell can be obtained through the existing digital phase-locked demodulation software and can be expressed as delta psir(t)＝argtan(S2fx(t)/S2fy(t)), wherein S2fx、S2fyThe time-varying components in the orthogonal coordinate system of the second harmonic signal are respectively, and the difference between the phase information of the gas molecule to be measured and the phase information of the reference absorption cell molecule spectrum can be expressed as: delta phi (t) ═ delta psim(t)-δψr(t) where δ ψm(t) converting the phase difference information into distance information in real time for compensating the distance L between the laser and the cooperative target2A change in (c).
The invention is not described in detail, and can be carried out by adopting the prior art.
The invention has the beneficial effects that:
1) the invention can measure the concentration information of more than two gases in the atmosphere in real time and realizes the compactness of the system.
2) The invention takes the laser spectrum absorption as the principle, adopts the technology based on digital wavelength modulation spectrum, the scanning frequency of the laser is more than 100Hz, the modulation frequency is more than 20KHz, because the cut-off frequency of the introduced noise of the atmospheric turbulence to the laser is below 100Hz, the noise introduced by the atmospheric turbulence can be effectively avoided according to the above parameters, thereby realizing the remote detection, the detection distance is farther than the current detection distance, and the measurement distance of the invention can reach more than 2km at most.
3) The invention adopts digital demodulation software and Kalman filtering algorithm, reduces the measuring time, improves the measuring sensitivity of the sensor, and the measuring sensitivity of the sensor is as follows before the noise filtering algorithm is not carried out: the integration time was 60s, the sensitivity was 50ppb, the measurement time was 1s and the sensitivity was 10ppb after using kalman filtering.
4) The invention can realize the measurement of the gas in the three-dimensional area by arranging the vertical scanning mirror, the horizontal rotating platform and the plurality of cooperative target reflecting mirrors, thereby obtaining the gas movement distribution characteristics.
Drawings
FIG. 1 is a schematic diagram of the configuration of one embodiment of a radial plume multi-component gas measurement remote sensing system of the present invention;
FIG. 2 is a schematic view of an arrangement of cooperating target mirrors in a plane;
FIG. 3 is a schematic view of one arrangement of cooperating target mirrors in a vertical plane;
the system comprises a data acquisition card 1, a laser 2, a laser A, a beam splitter 3, a beam splitter A, a reference absorption pool 4, a reference absorption pool A, a first detector A, a beam splitter 6, a beam combiner 7, a beam expander 8, a target reflector 9, a reflector 10, a first lens 11, a second lens 12, a narrow-band filter A13, a reference absorption pool B14, a first detector B15, a second detector A16, a second detector B17, a second detector B18, a second lens B19, a narrow-band filter B20, a grating 21, a laser B22 and an integrated structure.
The specific implementation mode is as follows:
in order to make the technical problems, technical solutions and advantages of the present invention more apparent, the following detailed description is given with reference to the accompanying drawings and specific examples, but not limited thereto, and the present invention is not described in detail and is in accordance with the conventional techniques in the art.
Example 1:
a radial plume multicomponent gas measurement remote sensing system, as shown in figure 1, the quantity of two lasers is 2, for the convenience of description, here only the apparatus that matches with the first laser adopts A to represent, only the apparatus that matches with the second laser adopts B to represent, except that the apparatus that many sets of laser systems share, this system includes reflecting laser acquisition unit and data acquisition unit;
the data acquisition unit comprises a data acquisition card and a computer 1 which are connected with each other, the data acquisition card 1 can realize the functions of data acquisition, A/D conversion and the like, and transmits the acquired photoelectric signals to the computer to realize calculation and analysis in the computer, the computer is a portable computer, the reflection laser acquisition unit comprises 2 lasers A2 and B21 which are connected with the data acquisition card respectively, the light of the laser A2 is divided into two paths by a beam splitter A3, one path of light irradiates to a first detector A5 by a reference absorption pool A4, the first detector A5 is connected with the data acquisition card 1, the other path of light irradiates to a beam expander 8 by a beam combiner 7, the beam expander 8 realizes beam expansion and collimation of the laser, so that the output laser has a smaller divergence angle, and a cooperative target reflector 9, a cooperative target reflector 9 and a cooperative target reflector are sequentially arranged along the light path of the beam expander 8, The light passes through the reflector 10 and the first lens 11, is converged to the grating 20 through the first lens 11, the separation of different wavelengths is realized at the grating 20, the light of different wavelengths is incident on the second detector A16 through the narrow-band filter A13 and the second lens A12, and the second detector A16 is connected with the data acquisition card 1;
similarly, light of a laser B21 is divided into two paths by a beam splitter B6, one path of light irradiates to a first detector B15 through a reference absorption cell B14, the first detector B15 is connected with the data acquisition card 1, the other path of light irradiates to a beam expander 8 through a beam combiner 7, the beam expander 8 expands and collimates the laser, so that the output laser has a small divergence angle, a cooperative target reflector 9, a reflector 10 and a first lens 11 are sequentially arranged along the light path direction of the beam expander 8, the light is converged to a grating 20 through the first lens 11, separation of different wavelengths is realized at the grating 20, the light of different wavelengths is incident to a second detector B17 through a narrow-band filter B19 and a second lens B18, and the second detector B17 is connected with the data acquisition card 1;
the laser A2 and the laser B21 are both modulatable semiconductor lasers, the scanning frequency of the modulatable semiconductor lasers is greater than 100Hz, and the modulation frequency is greater than 20kHz, so that the laser is used for inhibiting the influence of atmospheric turbulence.
Example 2:
a radial plume multicomponent gas measurement remote sensing system, the structure of which is as shown in embodiment 1, except that a vertical scanning mirror (not shown in the figure) is further disposed between a beam expander 8 and a cooperative target reflecting mirror 9, and a light beam is irradiated to the cooperative target reflecting mirror 9 through the vertical scanning mirror along the beam expander 8, then irradiated to a reflecting mirror 10 through the vertical scanning mirror, and converged to a grating 20 through a first lens 11;
the system comprises a plurality of lasers, a beam splitter, a reference absorption cell, a first detector, a beam combiner, a beam expander, a vertical scanning mirror, a reflector, a first lens, a grating, a narrow-band filter, a second lens and a second detector which are respectively connected with the plurality of lasers, wherein the beam splitter, the reference absorption cell, the first detector, the beam combiner, the beam expander, the vertical scanning mirror, the reflector, the first lens, the grating, the narrow-band filter, the second lens and the second detector are integrated into a whole structure 22 and are arranged on a horizontal rotating platform, so that the gas concentration measurement in a horizontal plane is realized, the structure of the horizontal rotating platform is not limited, and the structure capable of realizing 360-degree rotation can be realized;
the number of the cooperative target reflecting mirrors 9 is plural, and the cooperative target reflecting mirrors are arranged in a certain horizontal plane to be measured and a certain vertical plane to be measured.
Example 3:
a radial plume multicomponent gas measurement remote sensing system, the structure of which is shown in embodiment 2, except that the vertical scanning mirror is a rotating prism, which is used to irradiate a horizontal light beam to a cooperative target reflector above or below a remote place, and then irradiate the light beam to the reflector through the vertical scanning mirror, so as to realize gas concentration measurement when the cooperative target reflector is vertically distributed.
Example 4:
a radial plume multi-component gas measurement remote sensing system is structurally shown in embodiment 1, except that a laser A2 and a laser B21 are both butterfly lasers, the wavelengths of the laser A2 and the laser B21 are 1500-2000nm, the selected laser wavelength can cover target gas molecular spectrums such as methane and ammonia molecules, and the power of the laser is preferably more than 10 mW;
the first detector A5, the first detector B15, the second detector A16 and the second detector B17 are all InGaAs APD detectors and are used for receiving high sensitivity and achieving collection of weak light signals of backscatter detection signals.
Example 5:
the structure of the remote sensing system for measuring the radial plume multicomponent gas is shown in embodiment 1, and is different from that the diameter of a cooperative target reflector 9 is 30-60mm, the distances between the cooperative target reflector 9 and a laser A and between the cooperative target reflector 9 and a laser B21 are more than 1000m, and the remote sensing system is suitable for measuring the gas concentration between the emission position of the laser and the cooperative target reflector, and realizes certain regional gas measurement.
Example 6:
the structure of a radial plume multi-component gas measurement remote sensing system is shown in embodiment 1, except that a reference absorption cell A4 and a reference absorption cell B14 are both filled with high-concentration reference gas, the concentration of the reference gas is more than or equal to 1%, and the adjustment can be performed according to the absorption molecular strength of a target gas.
An optical window is arranged in the reflector 10, and the effective aperture of the optical window is 50 mm.
Example 7:
the structure of a remote sensing system for measuring radial plume multi-component gas is shown in embodiment 1, and is different from the structure that a data acquisition card 1 is NI-6531 of NI company, the channel mode of the data acquisition card 1 is 16 channels, the measurement speed is 3MHz, and the interface mode is a USB interface.
Example 8:
a radial plume multi-component gas measurement remote sensing system, the structure of which is shown in example 1, except that the grating 20 is a blazed grating, the dimension of the blazed grating is 25mm × 25mm, the angle of the blazed grating is 28 °, and the grating stripes are 600/mm; the grating is used for realizing two-way or multi-way light spot separation.
Example 9:
the utility model provides a radial plume multicomponent gas measures remote sensing system, the structure is as shown in embodiment 1, and the difference is that the central wavelength of narrowband filter A16 and narrowband filter B17 suits with the central wavelength of the absorption peak of the gas that awaits measuring, here is 1578nm and 1521nm respectively, suits at central wavelength 1578nm and 1521nm with gas methane and ammonia that awaits measuring respectively, the bandwidth of narrowband filter is 1.5nm, and here narrowband interference filter can restrain the stray light beyond the central wavelength, and the echo signal after the output, and narrowband filter and convex lens cooperation are used for realizing that the facula assembles.
The first lens 11 is a convex lens, the focal length of which is 50mm, and light spot convergence is realized.
Example 10:
the structure of a radial plume multi-component gas measurement remote sensing system is shown in embodiment 1, except that the beam expansion multiple of a beam expander 8 is 10 times, and the divergence angle of a field of view of a laser A2 or a laser B21 can be compressed to 0.1mrad, so that a good result of the remote sensing system can be ensured.
While the foregoing is directed to the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the appended claims.
Claims (6)
1. A remote sensing system for measuring a multi-component gas with a radial plume, wherein the radial plume refers to a gas which is distinguished from a surrounding gas medium along a laser measuring direction due to gas leakage or emission, and is characterized by comprising a reflection laser acquisition unit and a data acquisition unit;
the data acquisition unit comprises a data acquisition card and a computer which are connected with each other, the data acquisition card is used for realizing data acquisition and A/D conversion, transmitting the acquired photoelectric signals to the computer, and calculating and analyzing in the computer;
the reflection laser acquisition unit comprises a plurality of lasers connected with the data acquisition card, light of each laser is divided into two paths through a beam splitter, one path of light irradiates to a first detector through a reference absorption pool, the first detector is connected with the data acquisition card, the other path of light irradiates to a beam expander through the beam combiner, a cooperation target reflector, a reflector and a first lens are sequentially arranged along a propagation path of light emitted by the beam expander, the light is converged to a grating through the first lens, separation of different wavelengths is realized at the grating, light of different wavelengths is incident to different second detectors through different narrow-band filters and different second lenses, and the second detectors are connected with the data acquisition card;
the laser, the beam splitter, the reference absorption cell, the first detector, the narrow-band filter, the second lens and the second detector are corresponding in number, and the number of the laser, the beam splitter, the reference absorption cell, the first detector, the narrow-band filter, the second lens and the second detector is more than two;
the laser is a modulatable semiconductor laser, the scanning frequency of the modulatable semiconductor laser is more than 100Hz, and the modulation frequency is more than 20 kHz;
a vertical scanning mirror is also arranged between the beam expander and the cooperative target reflecting mirror, and light beams are irradiated to the cooperative target reflecting mirror through the vertical scanning mirror along the beam expander, then irradiated to the reflecting mirror through the vertical scanning mirror and converged to a grating through a first lens;
the system comprises a plurality of lasers, and a beam splitter, a reference absorption cell, a first detector, a beam combiner, a beam expander, a vertical scanning mirror, a reflector, a first lens, a grating, a narrow-band filter, a second lens and a second detector which correspond to the plurality of lasers, which are integrated into a whole and are arranged on a horizontal rotating platform to realize gas concentration measurement in a horizontal plane;
the number of the cooperative target reflecting mirrors is multiple and is vertically distributed;
the vertical scanning mirror is a scanning galvanometer or a rotating prism;
the diameter of the cooperative target reflector is 30-60mm, and the distance between the cooperative target reflector and the laser is more than 1000 m; the system is suitable for measuring the gas concentration between the emission position of the laser and the cooperative target reflector, and realizes regional gas measurement;
the central wavelength of the narrow-band filter is adapted to the central wavelength of the absorption peak of the gas to be detected, and the bandwidth of the narrow-band filter is 1.5 nm;
the working principle of the radial plume multi-component gas measurement remote sensing system is as follows:
two paths of scanning and modulating signals are generated by a data acquisition card, each path of scanning and modulating signal is used for driving the current of a modulation laser to realize the modulation of the output wavelength of the laser, the signals are respectively a first harmonic wave and a second harmonic wave, the output lasers of the two paths of lasers are respectively divided into two paths through a beam splitter, wherein the two paths of lasers with weaker energy realize photoelectric conversion through a reference absorption cell filled with reference gas and a first detector, and S is used for converting the output wavelength of the laser into S-shaped laser beams11r、S12rRespectively representing a first harmonic signal amplitude value and a second harmonic signal amplitude value of a reference absorption pool, collimating two paths of laser with stronger energy through a beam combiner, then reflecting by a cooperative target reflector after the transmission distance of the laser in an open circuit space is more than 1000m, realizing the separation of different wavelengths on a grating after the laser is converged by the reflector and a first lens, and respectively obtaining a first harmonic signal amplitude value and a second harmonic signal amplitude value of the reference absorption poolThe convergence of the band filter and the second lens realizes photoelectric conversion on the second detector to S11、S12Respectively representing the first harmonic signal amplitude value and the second harmonic signal amplitude value of the remote sensing measurement with stronger energy, and knowing the distance L between the cooperative target reflector and the laser2Length L of reference absorption cell1And concentration information C of reference gas in the reference absorption cell1Obtaining the open-circuit measurement gas concentration as follows:
UC1＝(S12r*S11)*L1*C1/(S12*S11r*L2) (1)
carrying out noise filtering on the obtained concentration information UC1, wherein a Kalman filtering algorithm is selected as a noise filtering algorithm;
the reference absorption cell is used for correcting phase change of modulated laser in the atmospheric transmission process, and the specific principle is as follows: obtaining phase information of a reference absorption cell through digital phase-locked demodulation software, wherein the phase information is expressed as delta psir(t)＝argtan(S2fx(t)/S2fy(t)), wherein S2fx(t)、S2fy(t) are respectively the time-varying components under the orthogonal coordinate system of the second harmonic signal, and the difference between the phase information of the gas molecule to be measured and the phase information of the reference absorption cell molecule spectrum is expressed as follows: delta phi (t) ═ delta psim(t)-δψr(t) where δ ψm(t) converting the phase difference information into distance information in real time for compensating the distance L between the laser and the mirror of the cooperative target2A change in (c).
2. The remote radial plume multicomponent gas measurement sensing system according to claim 1, wherein the laser wavelength range is 1.5-2 μm, laser power >10 mW;
the first detector and the second detector are both InGaAs APD detectors;
the laser is a butterfly laser, a quantum cascade laser or an interband cascade laser.
3. The remote radial plume multicomponent gas measurement sensing system of claim 1, wherein the reference absorption cell contains a high concentration of reference gas, the concentration of reference gas being greater than or equal to 1%.
4. The remote sensing system for measuring radial plume multicomponent gas according to claim 1, wherein the two ends inside the reference absorption cell are optical fiber ports, or the reference absorption cell is provided with a glass window;
the data acquisition card is NI-6531 of NI company, the measuring speed of the data acquisition card is 3MHZ, and the interface form is a USB interface.
5. The remote sensing system for measuring radial plume multicomponent gas, as recited in claim 1, wherein the grating is blazed grating, the blazed grating angle is 25-30 °, and the grating stripe is 500-700 stripes/mm.
6. The remote radial plume multicomponent gas measurement sensing system of claim 1, wherein the beam expander has a beam expansion multiple of 10.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911380938.XA CN111122499B (en) | 2019-12-27 | 2019-12-27 | Radial plume multi-component gas measurement remote sensing system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911380938.XA CN111122499B (en) | 2019-12-27 | 2019-12-27 | Radial plume multi-component gas measurement remote sensing system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111122499A CN111122499A (en) | 2020-05-08 |
| CN111122499B true CN111122499B (en) | 2021-09-17 |
Family
ID=70504733
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911380938.XA Active CN111122499B (en) | 2019-12-27 | 2019-12-27 | Radial plume multi-component gas measurement remote sensing system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111122499B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112432664B (en) * | 2020-11-11 | 2022-04-08 | 山东大学 | All-fiber laser detection system for tunnel safety monitoring and working method |
| CN114354538A (en) * | 2022-03-22 | 2022-04-15 | 朗思传感科技(深圳)有限公司 | Laser gas sensing device and gas detection method |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103411919A (en) * | 2013-07-03 | 2013-11-27 | 安徽建筑大学 | System and method for simultaneously monitoring multiple components of building fire early-stage characteristic gases |
| CN106018339A (en) * | 2016-07-08 | 2016-10-12 | 山东微感光电子有限公司 | Self-adaption reflection-type infrared laser industrial dangerous leaking gas monitoring device |
| CN108132228A (en) * | 2017-12-21 | 2018-06-08 | 宁波海尔欣光电科技有限公司 | A kind of vehicle exhaust telemetering equipment |
| CN110320178A (en) * | 2019-07-17 | 2019-10-11 | 电子科技大学 | A kind of gas detecting system and its detection method based on wavelength modulation spectrum technology |
-
2019
- 2019-12-27 CN CN201911380938.XA patent/CN111122499B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103411919A (en) * | 2013-07-03 | 2013-11-27 | 安徽建筑大学 | System and method for simultaneously monitoring multiple components of building fire early-stage characteristic gases |
| CN106018339A (en) * | 2016-07-08 | 2016-10-12 | 山东微感光电子有限公司 | Self-adaption reflection-type infrared laser industrial dangerous leaking gas monitoring device |
| CN108132228A (en) * | 2017-12-21 | 2018-06-08 | 宁波海尔欣光电科技有限公司 | A kind of vehicle exhaust telemetering equipment |
| CN110320178A (en) * | 2019-07-17 | 2019-10-11 | 电子科技大学 | A kind of gas detecting system and its detection method based on wavelength modulation spectrum technology |
Non-Patent Citations (1)
| Title |
|---|
| 免标定的TDLAS氧气在线测量系统;康信文;《中国优秀硕士学位论文全文数据库 工程科技Ⅰ辑》;20180415(第4期);1-48 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN111122499A (en) | 2020-05-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101105446B (en) | Differential optical absorption spectroscopy air quality detection system | |
| US7884937B2 (en) | Airborne tunable mid-IR laser gas-correlation sensor | |
| US6455851B1 (en) | Spectroscopic remote sensing exhaust emission monitoring system | |
| CA2630301C (en) | Mobile remote detection of fluids by a laser | |
| CN103115894B (en) | Stable isotopic abundance ratio real-time online monitoring device and method | |
| CN108414469B (en) | TDLAS (tunable diode laser absorption Spectroscopy) scanning-based transceiver integrated motor vehicle tail gas remote sensing measurement device and method | |
| CN109991189B (en) | Fixed point wavelength modulation gas concentration measuring device based on wave number drift correction and measuring method thereof | |
| CN104596987A (en) | Mid-infrared spectroscopy-based trace gas detection method and device combining long-optical-path open light path with wavelength modulation technique | |
| CN101819140B (en) | Continuous monitoring device and method of gaseous elemental mercury concentration | |
| US20220026577A1 (en) | Dispersion gating-based atmospheric composition measurement laser radar | |
| CN104280362A (en) | Online high-temperature water vapor laser spectrum detection system | |
| CN111122499B (en) | Radial plume multi-component gas measurement remote sensing system | |
| CN109668834A (en) | Analytical equipment, multipath reflection pond and analysis method | |
| Shen et al. | Methane near-infrared laser remote detection under non-cooperative target condition based on harmonic waveform recognition | |
| CN109813639B (en) | Infrared light modulation technology-based synchronous measurement device and measurement method for concentration of particulate matters and gas | |
| CN114384045B (en) | Trace gas concentration and path length real-time detection system and method | |
| CN111239072B (en) | Method for accurately measuring temperature of combustion gas | |
| CN111208084A (en) | Optical fiber gas concentration remote sensing detection device and method based on coherent detection method | |
| CN113834788A (en) | Laser spectrum multipoint detection system and method for ammonia volatilization flux of farmland | |
| Geiko et al. | Detection of concentration small gas components of atmosphere by DOAS method | |
| CN211528208U (en) | Optical fiber gas concentration remote sensing detection device based on coherent detection method | |
| US8445850B2 (en) | Optical remote sensing of fugitive releases | |
| Cui et al. | Environmental application of high sensitive gas sensors with tunable diode laser absorption spectroscopy | |
| CA2087439C (en) | Ftir remote sensor apparatus and method | |
| RU201025U1 (en) | TWO-CHANNEL LIDAR NEXT IR RANGE |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20220928 Address after: Room 101, 1st Floor, Block C, Kaibet Building, No. 15 Huaxin Road, Licheng District, Jinan City, Shandong Province, 250100 Patentee after: Shandong birui Laser Technology Co.,Ltd. Address before: No. 27, mountain Dana Road, Ji'nan City, Shandong, Shandong Patentee before: SHANDONG University |
|
| TR01 | Transfer of patent right |