CN113310857B - Turbulent combustion field four-dimensional carbon smoke particle primary particle size distribution measuring system and method thereof - Google Patents
Turbulent combustion field four-dimensional carbon smoke particle primary particle size distribution measuring system and method thereof Download PDFInfo
- Publication number
- CN113310857B CN113310857B CN202110584029.9A CN202110584029A CN113310857B CN 113310857 B CN113310857 B CN 113310857B CN 202110584029 A CN202110584029 A CN 202110584029A CN 113310857 B CN113310857 B CN 113310857B
- Authority
- CN
- China
- Prior art keywords
- detection system
- signal detection
- laser
- signal
- dimensional
- 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
- 238000002485 combustion reaction Methods 0.000 title claims abstract description 57
- 238000000034 method Methods 0.000 title claims abstract description 56
- 239000002245 particle Substances 0.000 title claims abstract description 39
- 239000011164 primary particle Substances 0.000 title claims abstract description 38
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 title claims abstract description 13
- 229910052799 carbon Inorganic materials 0.000 title claims abstract description 13
- 239000000779 smoke Substances 0.000 title claims abstract description 12
- 239000004071 soot Substances 0.000 claims abstract description 47
- 238000004587 chromatography analysis Methods 0.000 claims abstract description 35
- 238000005259 measurement Methods 0.000 claims abstract description 25
- 238000009529 body temperature measurement Methods 0.000 claims abstract description 20
- 238000001514 detection method Methods 0.000 claims description 189
- 230000005855 radiation Effects 0.000 claims description 47
- 230000003287 optical effect Effects 0.000 claims description 26
- 230000008569 process Effects 0.000 claims description 14
- 230000007935 neutral effect Effects 0.000 claims description 10
- 238000012545 processing Methods 0.000 claims description 7
- 230000035945 sensitivity Effects 0.000 claims description 7
- 238000001228 spectrum Methods 0.000 claims description 7
- 230000003111 delayed effect Effects 0.000 claims description 5
- 230000001960 triggered effect Effects 0.000 claims description 4
- 238000012360 testing method Methods 0.000 abstract description 7
- 238000004458 analytical method Methods 0.000 abstract description 3
- 238000000295 emission spectrum Methods 0.000 abstract description 2
- 238000005516 engineering process Methods 0.000 description 6
- 238000010586 diagram Methods 0.000 description 5
- 238000003325 tomography Methods 0.000 description 4
- 230000015572 biosynthetic process Effects 0.000 description 3
- 239000011159 matrix material Substances 0.000 description 3
- 230000008859 change Effects 0.000 description 2
- 238000003745 diagnosis Methods 0.000 description 2
- 238000004134 energy conservation Methods 0.000 description 2
- 230000005284 excitation Effects 0.000 description 2
- 238000003384 imaging method Methods 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- 239000000523 sample Substances 0.000 description 2
- 238000005070 sampling Methods 0.000 description 2
- 238000004861 thermometry Methods 0.000 description 2
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 238000005054 agglomeration Methods 0.000 description 1
- 230000002776 aggregation Effects 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000003344 environmental pollutant Substances 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 239000005431 greenhouse gas Substances 0.000 description 1
- 230000036541 health Effects 0.000 description 1
- 230000017525 heat dissipation Effects 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 229910052744 lithium Inorganic materials 0.000 description 1
- 238000012067 mathematical method Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012634 optical imaging Methods 0.000 description 1
- 230000008520 organization Effects 0.000 description 1
- 231100000719 pollutant Toxicity 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000000859 sublimation Methods 0.000 description 1
- 230000001052 transient effect Effects 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume or surface-area of porous materials
- G01N15/02—Investigating particle size or size distribution
- G01N15/0205—Investigating particle size or size distribution by optical means
Landscapes
- Chemical & Material Sciences (AREA)
- Dispersion Chemistry (AREA)
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating, Analyzing Materials By Fluorescence Or Luminescence (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
Abstract
The invention discloses a system and a method for measuring the primary particle size distribution of four-dimensional carbon smoke particles in a turbulent combustion field, which solves the problem that the required test in turbulent combustion cannot be actually achieved by the existing test means, the technical scheme is that the method is characterized in that the method realizes the measurement of a turbulent flame temperature field based on an emission spectrum chromatography colorimetric temperature measurement system, detects a laser-induced incandescent light signal based on a chromatography laser-induced incandescent light system, combines a laser-induced incandescent light model, fitting the attenuation curve of the laser-induced incandescent light signal in each voxel in the discretized reconstruction area to finally obtain the spatial distribution of the primary particle size of the soot particles, the turbulent combustion field four-dimensional soot particle primary particle size distribution measuring system and the method thereof, the temperature distribution and the primary particle size distribution of the time-space analysis can be obtained simultaneously, and the method is finally used for researching the generation and evolution rules of the carbon smoke particles in the turbulent flame.
Description
Technical Field
The invention relates to the technologies of combustion diagnosis, radiation temperature measurement, computational imaging and soot diagnosis, in particular to a system and a method for measuring the primary particle size distribution of four-dimensional soot particles in a turbulent combustion field.
Background
In recent years, the development and utilization of new energy is a hot topic. However, despite the increasing importance of lithium batteries, fuel cells and other electrical devices in power plants, automotive internal combustion engines and aircraft engines continue to dominate the worldwide transportation industry. However, during combustion, pollutants such as greenhouse gases and soot particles are inevitably generated. This will cause environmental pollution and harm to human health.
In order to reduce soot emissions, sufficient knowledge of the soot formation process is required. The soot generation processes such as agglomeration, surface growth and oxidation depend to a large extent on the specific surface area of the soot particles. Thus, the size (diameter d) of the primary particles p ) Is a main index for representing the evolution process of the soot. In addition, soot generation and oxidation are also closely related to local temperature; at the same time, the temperature also has a great influence on the kinetics of the combustion chemical reaction, especially under the effect of turbulence. Therefore, in order to better understand the soot generation process and to establish an effective soot generation model, we must obtain the above mentioned parameters, such as primary particle size and flame local temperature, etc., during the combustion process.
In practical combustion devices, such as gas turbines and internal combustion engines, turbulent combustion is the predominant form of combustion organization. In turbulent combustion, soot generation is a three-dimensional physicochemical process, and the time scale is often on the order of milliseconds or even sub-milliseconds. However, the current testing methods have not been able to meet the above-mentioned testing requirements.
Disclosure of Invention
The invention aims to provide a turbulent combustion field four-dimensional soot particle primary particle size distribution measuring system and a method thereof, which can simultaneously obtain the temperature distribution and the primary particle size distribution of space-time analysis and are finally used for researching the generation and evolution rules of soot particles in turbulent flame.
The technical purpose of the invention is realized by the following technical scheme:
a turbulent combustion field four-dimensional soot particle primary particle size distribution measuring method comprises the following steps:
s1, building a laser light path system, installing a high-frequency laser, installing an optical component along the light path, a burner to be tested positioned in the laser light path, and a first signal detection system for recording the light intensity distribution of the laser in real time;
s2, establishing a colorimetric radiation temperature measurement system based on endoscopic chromatography, uniformly distributing a plurality of incident ends of a first one-by-one multi-endoscope at the same side of the same radius circumference outside a combustor to be measured, aligning the incident end of a first spectroscope to the emergent end of the first one-by-one multi-endoscope, and respectively aligning a second signal detection system and a third signal detection system to two emergent ends of the first spectroscope;
s3, establishing a laser-induced incandescent light signal measuring system based on endoscopic chromatography, and uniformly distributing a plurality of incident ends of a second one-in-many endoscope to the same side of the same radius circumference outside the combustor to be measured; the incident end of the second spectroscope is aligned to the emergent end of the second multi-splitting endoscope, and the fourth signal detection system and the fifth signal detection system are respectively aligned to the two emergent ends of the second spectroscope;
s4, setting and triggering a colorimetric radiation temperature measurement system and a laser-induced incandescent light signal measurement system through a signal generator; the signal generator is used for setting a first signal detection system to synchronously trigger with a second signal detection system and a third signal detection system, setting a fourth signal detection system to delay for triggering, and setting a certain delay between a fifth signal detection system and the first signal detection system as well as the fourth signal detection system;
s5, a first signal detection system, a second signal detection system, a third signal detection system, a fourth signal detection system and a fifth signal detection system respectively collect and process multi-angle signals to obtain four-dimensional distribution of combustion field temperature distribution and primary particle size of soot particles.
In conclusion, the invention has the following beneficial effects:
measuring a turbulent flame temperature field based on an emission spectrum chromatography colorimetric temperature measurement system, detecting a laser-induced incandescent light signal based on a chromatography laser-induced incandescent light system, fitting an attenuation curve of the laser-induced incandescent light signal in each voxel in a discretized reconstruction region by combining a laser-induced incandescent light model, and finally obtaining the primary particle size spatial distribution of carbon soot particles;
by adopting a time delay detection scheme and using a high repetition frequency pulse laser and a high-speed camera in a matching way, the time analysis measurement of the turbulent combustion field can be realized; by the application of the chromatography technology, the measurement of the space resolution of the turbulent combustion field can be realized. By combining the chromatography colorimetric temperature measurement system with the chromatography laser induced incandescent light system, the time-space resolution measurement of the primary particle size distribution of the carbon smoke particles in the turbulent combustion field, namely the four-dimensional (3D + t) measurement, can be realized.
Drawings
FIG. 1 is a schematic diagram of a system according to an embodiment of the present invention;
FIG. 2 is a schematic timing diagram of trigger signals of the signal detection systems;
fig. 3 is a schematic diagram of the relative position relationship among the world coordinate system, the camera coordinate system and the image coordinate system in the three-dimensional inversion model.
In the figure: 1. a high frequency laser; 2. a spherical concave lens; 3. a first cylindrical convex lens; 4. a second cylindrical convex lens; 5. a mirror; 6. a burner to be tested; 7. a neutral density attenuation sheet; 8. a first high-speed camera; 81. a first lens; 9. a sixth lens; 10. a first one-to-many endoscope; 11. a first beam splitter; 12. a first band filter; 13. a second lens; 14. a second high-speed camera; 15. a second band filter; 16. a third lens; 17. a third high-speed camera; 18. a signal generator; 19. a seventh lens; 20. a second one-in-many endoscope; 21. a second spectroscope; 22. a first third band filter; 23. a fourth lens; 24. a first image intensifier; 25. a fourth high-speed camera; 26. a second third band filter; 27. a fifth lens; 28. a second image intensifier 29, a fifth high-speed camera.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings.
At present, the soot testing technology is mainly divided into invasive and non-invasive. The intrusive method is mainly based on a sampling method, which obtains a sample of soot by a probe and determines the particle size of soot primary particles and the parameters of agglomerates by using a Transmission Electron Microscope (TEM). However, the intrusive sampling approach inevitably destroys the combustion process, thereby causing measurement errors; furthermore, the method is very time consuming and does not allow to resolve the soot formation process. The non-invasive method can effectively avoid the problems. Such methods primarily include various optical testing techniques. The laser induced glow (LII) technique heats soot particles by short laser pulses to emit intense glow, and the peak intensity of the glow is directly related to the volume fraction f of soot V Is in direct proportion. On the other hand, due to the soot primary particle diameter d p Determines the rate of heat dissipation and therefore the rate of decay of the incandescent light. By conservation of energy, the rate of deceleration of the red-light decay and d can be established p The LII model is established. Therefore, if the decay rate of the incandescent light signal is obtained by the time-resolved laser-induced incandescent light (TiRe-LII) technology, d can be obtained according to the LII model p . The technology can only measure the soot parameters of a single point at the beginning of the invention. In 1995, a two-dimensional TiRe-LII technology was first proposed, namely d is imaged p The distribution of (c) is measured.
The LII signal attenuation time scale is hundreds of nanoseconds, and due to the lack of an ultra-high speed camera, the LII signal can be excited by using a plurality of laser pulses only aiming at a steady flame in the past measurement, so that different points on an attenuation curve are obtained, and the attenuation rate is fitted. Therefore, it is not suitable for the measurement of an unsteady turbulent flame.
Optical imaging methods have become an indispensable tool for turbulent combustion research today. As described above, planar imaging methods, such as the two-dimensional TiRe-LII technique, can be used to measure soot parameter distribution in the laser excitation plane. However, the formation of soot in turbulent combustion is a three-dimensional physicochemical process, and two-dimensional measurement cannot be completely resolved. Therefore, there is a need to develop testing techniques with higher dimensional resolution. One possible solution is to scan the flame layer by layer. However, due to the high-speed dynamic change characteristic of turbulent flame, the layer-by-layer scanning cannot capture the transient three-dimensional distribution of soot particles. The other scheme is that a volume laser column is adopted to excite the whole flame to generate an LII signal, projections (namely integration) of the LII signal are collected at a plurality of angles, the spatial distribution of the LII signal is reconstructed by a chromatography method, and finally, the local soot parameters are obtained.
Essentially, tomography is a powerful mathematical method that can reconstruct the object field itself by projection of the object field (e.g., the three-dimensional distribution of the LII signal) over multiple angles. In recent years, optical tomography has been advanced to a great extent, and has become an important means for studying turbulent combustion. More recently, Meyer et al have reconstructed the jet flame soot volume fraction f by combining LII techniques with the principles of chromatography V Three-dimensional distribution of (a). However, the primary particle size d was not achieved due to failure to measure the decay rate of the LII signal p And (4) measuring three-dimensional distribution.
According to one or more embodiments, a turbulent combustion field four-dimensional soot primary particle size distribution measuring system is disclosed, as shown in fig. 1, and includes a laser optical path system, a colorimetric radiation thermometry system based on endoscopic chromatography, a laser-induced incandescent light signal measuring system based on endoscopic chromatography, and a signal generator 18.
The laser optical path system comprises a high-frequency laser 1 for emitting laser beams, and further comprises a spherical concave lens 2, a first cylindrical convex lens 3, a second cylindrical convex lens 4, a reflector 5, a combustor 6 to be detected, a neutral density attenuation sheet 7 and a first signal detection system for collecting laser signals in real time, wherein the spherical concave lens 2, the first cylindrical convex lens 3, the second cylindrical convex lens 4, the reflector 5, the combustor 6 to be detected and the neutral density attenuation sheet 7 are sequentially arranged along an optical path. The first cylindrical convex lens 3 and the second cylindrical convex lens 4 respectively expand the laser beam in width and height; wherein, the distance between the first cylindrical convex lens 3 and the spherical concave lens 2 is the difference between the absolute values of the focal lengths of the first cylindrical convex lens 3 and the spherical concave lens 2; the distance between the second cylindrical convex lens 4 and the spherical concave lens 2 is equal to the difference between the absolute focal lengths of the second cylindrical convex lens 4 and the spherical concave lens 2.
The colorimetric radiation temperature measurement system based on the endoscopic chromatography comprises a first one-to-many endoscope 10, a first spectroscope 11, a second signal detection system and a third signal detection system; the first one-to-many endoscope 10 comprises a plurality of incident ends and an emergent end, and the plurality of incident ends of the first one-to-many endoscope 10 are uniformly distributed on the same side of the circumference with the same radius outside the combustor 6 to be tested; the first spectroscope 11 comprises an incident end and two emergent ends, and the incident end of the first spectroscope 11 is aligned with the emergent end of the first one-to-many endoscope 10; the second signal detection system and the third signal detection system are respectively aligned with two emergent ends of the first beam splitter 11.
The laser-induced incandescent light signal measuring system based on the endoscopic tomography comprises a second multi-split endoscope 20, a second spectroscope 21, a fourth signal detection system and a fifth signal detection system. The second one-to-many endoscope 20 comprises a plurality of incident ends and an emergent end, the plurality of incident ends of the second one-to-many endoscope 20 are uniformly distributed on the same side of the circumference of the same radius outside the combustor 6 to be tested, and the first one-to-many endoscope and the second one-to-many endoscope 20 are respectively arranged on different sides of the combustor 6 to be tested and are positioned on two sides of a laser light path of the laser light path system. The second beam splitter 21 includes an entrance end aligned with the exit end of the second multi-split endoscope 20 and two exit ends for splitting the beam. The fourth signal detection system and the fifth signal detection system respectively correspond to two emergent ends of the second spectroscope 21.
The first signal detection system is positioned on the other side, opposite to the combustor 6 to be tested, of the neutral density attenuation sheet 7 and used for recording laser intensity distribution in real time, and comprises a first lens 81 and a first high-speed camera 8, wherein the neutral density attenuation sheet 7 is positioned on the front side of the first lens 81 and used for attenuating laser beam energy, and the first high-speed camera 8 is prevented from being damaged.
The splitting ratio of the first beam splitter 11 is 1: 1; since the laser-induced incandescent light signal decays with time, in order to obtain a higher signal-to-noise ratio, the splitting ratio of the second beam splitter 21 is 3: 7.
the second signal detection system comprises a first waveband optical filter 12, a second lens 13 and a second high-speed camera 14 which are sequentially connected from an incident end to an emergent end; the third signal detection system comprises a second waveband optical filter 15, a third lens 16 and a third high-speed camera 17 which are connected in sequence; the fourth signal detection system comprises a first third band filter 22, a fourth lens 23, a first image intensifier 24 and a fourth high-speed camera 25 which are connected in sequence; the fifth signal detection system comprises a second third band filter 26, a fifth lens 27, a second image intensifier and a fifth high-speed camera which are connected in sequence. The first and second band filters 15 are narrow band filters with different central wavelengths, and the combination of the central wavelengths of the first and second band filters 15 has high temperature sensitivity and can measure signals with high signal-to-noise ratio; the first and second filters 22 and 26 are used for detecting the laser-induced incandescent light signal.
The sixth lens 9 is disposed in front of a plurality of incident ends of the first one-by-one endoscope 10, and the seventh lens 19 is disposed in front of a plurality of incident ends of the second one-by-one endoscope 20.
The signal generator 18 is provided with a laser light path system, a colorimetric radiation temperature measurement system and the triggering of a laser-induced incandescent light signal measurement system, is connected with the high-frequency laser 1 and each signal detection system, and is used for setting signal triggering. The signal generator 18 is provided with a first signal detection system which is synchronously triggered with a second signal detection system and a third signal detection system, a fourth signal detection system is delayed to trigger with the first signal detection system, a fifth signal detection system is provided with a certain delay relative to the fourth signal detection system, the fifth signal detection system is also delayed to set corresponding to the first signal detection system, and the delay set between the fifth signal detection system and the first signal detection system as well as between the fifth signal detection system and the fourth signal detection system is nanosecond-level delay time, so that the laser-induced incandescent light measurement system based on the endoscopic chromatography can detect and obtain the attenuation curve of the laser-induced incandescent light signal under the same laser pulse.
The combustor 6 to be tested works under the turbulent flow working condition and the working state of the high-frequency laser 1, the signal generator 18 triggers each signal detection system to detect and collect signals according to the setting, records and stores the signals, the four-dimensional temperature distribution of the turbulent flow combustion field is obtained through the data processing of the colorimetric radiation temperature measurement system based on endoscopic chromatography, and the four-dimensional carbon smoke particle primary particle size distribution of the turbulent flow combustion field is obtained through the data processing of the laser-induced incandescent light signal measurement system based on endoscopic chromatography.
According to one or more embodiments, a turbulent combustion field four-dimensional soot particle primary particle size distribution measuring method is disclosed, which comprises the following steps:
s1, building a laser light path system, and installing a high-frequency laser 1, an optical component installed along the light path, a burner 6 to be tested located in the laser light path, and a first signal detection system for recording the light intensity distribution of the laser in real time.
S2, establishing a colorimetric radiation temperature measurement system based on endoscopic chromatography, uniformly distributing a plurality of incident ends of a first one-by-one multi-endoscope 10 at the same side of the same radius circumference outside a combustor 6 to be measured, aligning the incident end of a first spectroscope 11 to the emergent end of the first one-by-one multi-endoscope 10, and respectively aligning a second signal detection system and a third signal detection system to two emergent ends of the first spectroscope 11.
S3, establishing a laser-induced incandescent light signal measuring system based on endoscopic chromatography, and uniformly arranging a plurality of incident ends of the second one-in-many endoscope 20 at the same side of the same radius circumference outside the combustor 6 to be measured; the incident end of the second beam splitter 21 is aligned with the emergent end of the second multi-splitting endoscope 20, and the fourth signal detection system and the fifth signal detection system are respectively aligned with the two emergent ends of the second beam splitter 21.
S4, setting and triggering the colorimetric radiation temperature measurement system and the laser-induced incandescent light signal measurement system through the signal generator 18; the signal generator 18 sets the first signal detection system to trigger synchronously with the second detection system and the third signal detection system, sets the fourth signal detection system to trigger in a delayed manner, and sets a certain delay between the fifth signal detection system and the first signal detection system and the fourth signal detection system.
S5, the first signal detection system, the second signal detection system, the third signal detection system, the fourth signal detection system and the fifth signal detection system respectively collect and process multi-angle signals to obtain four-dimensional distribution of combustion field temperature distribution and primary particle size of soot particles.
Preferably, the first cylindrical convex lens 3 and the second cylindrical convex lens 4 in the laser optical path system expand the laser beam in width and height respectively; wherein, the distance between the first cylindrical convex lens 3 and the spherical concave lens 2 is the difference between the absolute values of the focal lengths of the first cylindrical convex lens 3 and the spherical concave lens 2; the distance between the second cylindrical convex lens 4 and the spherical concave lens 2 is equal to the difference between the absolute focal lengths of the second cylindrical convex lens 4 and the spherical concave lens 2.
Preferably, the first signal detection system is used for recording the laser light intensity distribution in real time and comprises a first lens 81 and a first high-speed camera 8; the neutral density attenuation sheet 7 is disposed in front of the first high-speed camera 8 and attenuates the laser beam energy to prevent it from damaging the first high-speed camera 8.
Preferably, the second signal detection system comprises a first waveband optical filter 12, a second lens 13 and a second high-speed camera 14 which are connected in sequence; the third signal detection system comprises a second waveband optical filter 15, a third lens 16 and a third high-speed camera 17 which are connected in sequence; the fourth signal detection system comprises a first third band filter 22, a fourth lens 23, a first image intensifier 24 and a fourth high-speed camera 25 which are connected in sequence; the fifth signal detection system comprises a second third band filter 26, a fifth lens 27, a second image intensifier 28 and a fifth high-speed camera 29 which are connected in sequence; a sixth lens 9 and a seventh lens 19 are respectively provided in front of the incident ends of the first and second one-by- one endoscopes 10 and 20.
Preferably, the splitting ratio of the first beam splitter 11 is 1: 1; since the laser-induced incandescent light signal decays with time, in order to obtain a higher signal-to-noise ratio, the splitting ratio of the second beam splitter 21 is 3: 7.
preferably, the first band filter 12 and the second band filter 15 adopt narrow band filters with different central wavelengths, and the combination of the central wavelengths of the first band filter 12 and the second band filter 15 has higher sensitivity to temperature and can measure signals with higher signal-to-noise ratio; the first and second filters 22 and 26 are used to detect the laser-induced incandescent light signal.
Preferably, a delay time of nanosecond level is required to be set between the trigger signals of the fifth signal detection system and the first, second, third and fourth signal detection systems, so that the laser-induced incandescent light measurement system based on endoscopic tomography can detect the attenuation curve of the laser-induced incandescent light signal under the same laser pulse. The timing diagram of the triggering scheme of each signal detection system is shown in fig. 2.
Preferably, step S5 further includes, but is not limited to, the steps of:
s51: calibrating each detection angle position in a colorimetric radiation temperature measurement system based on endoscopic chromatography and a laser-induced incandescent light signal measurement system based on endoscopic chromatography;
s52: when the combustor 6 to be tested does not work, the wide-spectrum standard light source with known absolute radiation intensity under different wavelengths is placed at the central position on the combustor 6 to be tested, the radiation signals of the wide-spectrum standard light source are respectively collected by a second signal detection system and a third signal detection system, and the calibration of the radiation signal intensity in the colorimetric radiation temperature measurement system based on the endoscopic chromatography is completed;
s53: carrying out data processing on a colorimetric radiation temperature measurement system based on endoscopic chromatography to obtain four-dimensional temperature distribution of a turbulent combustion field;
s54: correcting laser-induced incandescent light signals detected by a fourth signal detection system and a fifth signal detection system in the laser-induced incandescent light signal measurement system based on endoscopic chromatography according to the real-time laser line type detected by the first signal detection system, and reducing the influence of uneven laser intensity distribution on a detected result;
s55: and (3) carrying out data processing on the laser-induced incandescent light signal measurement system based on endoscopic chromatography to obtain the primary particle size distribution of the four-dimensional carbon smoke particles in the turbulent combustion field.
Preferably, the light-emitting wavelength of the broad spectrum standard light source includes the band-pass intervals of the first band filter 12 and the second band filter 15.
Preferably, step S51 further includes, but is not limited to, the steps of:
s511: a black and white lattice calibration plate with a known lattice size is placed at the center position of the combustor 6 to be tested, the position of the calibration plate is adjusted, black and white lattice images on the calibration plate are respectively and simultaneously collected from a plurality of angles in the first one-to-many endoscope 10 and the second one-to-many endoscope 20, and the black and white lattice images are respectively recorded and stored through the second signal detection system, the third signal detection system, the fourth signal detection system and the fifth signal detection system;
s512: respectively extracting intersection points of black and white grids in calibration plate images of different angles, which are simultaneously shot in each signal detection system, according to calibration plate data detected by the second, third, fourth and fifth signal detection systems, and obtaining coordinates of the intersection points under each camera coordinate system and the world coordinate system in different signal detection systems;
s513: and obtaining required calibration parameters by combining the coordinates of the grid intersection points in different camera coordinate systems and world coordinate systems and a calibration algorithm, and determining the position relationship between the second, third, fourth and fifth signal detection systems and the combustion field area to be detected and the relative position relationship between different detection angles in each signal detection system according to the calibration parameters.
Preferably, step S53 further includes, but is not limited to, the steps of:
s531: enabling the combustor 6 to be tested to work under a turbulent working condition and the high-frequency laser 1 to work, triggering each signal detection system according to the time delay triggering scheme in the step S4, and recording and storing data acquired by each signal detection system;
s532: establishing an inversion model of a radiation signal field by adopting a Monte Carlo ray tracing method and respectively combining a second signal detection system and a third signal detection system obtained in a calibration process and the position relation among a plurality of detection angles:
referring to fig. 3, fig. 3 is a schematic diagram illustrating a relative relationship among a world coordinate system, a camera coordinate system, and an image coordinate system involved in three-dimensional reconstruction. The light intensity received by a pixel on the camera coordinate system can be mathematically expressed as:
p(x p ，y p )＝∫∫∫f(x w ，y w ，z w )·W(x w ，y w ，z w ，x p ，y p )dV (1)
wherein p (x) p ，y p ) Is a camera pixel (x) p ，y p ) The measured light intensity; f (x) w ，y w ，z w ) Is a certain point (x) in space w ，y w ，z w ) The physical quantity to be measured; w is the coefficient matrix. If the region to be measured is discretized, equation (1) can be expressed as:
wherein N represents the overall prime number; Δ x, Δ y, Δ z are the size of the voxels along the x, y, z directions of the three coordinate axes, respectively. As can be seen from equation (2), each pixel on the camera actually provides a linear equation system, and the variables in the equation are the measured physical quantities of all voxels in the reconstruction region. Therefore, all pixels on the camera provide a series of linear equations. When the area to be measured is shot from different angles, a plurality of linear equation sets can be obtained, and the vector form can be expressed as follows:
wherein,
is a vector representing the set of radiation signals acquired by all pixels on the camera; each column in the matrix W represents a point spread function of a certain voxel on the camera;
the radiation signal field of all voxels in space is represented.
S533: solving an inversion problem by combining the inversion model of the radiation signal field and adopting an algebraic reconstruction method, and reconstructing three-dimensional relative radiation signal distribution of a combustion field area to be measured under a first wave band and a second wave band respectively;
the algebraic reconstruction method can reconstruct a better physical field to be measured under fewer projections, and can effectively inhibit the problem of artifacts. The error is used to update the reconstructed field in each iteration to progressively approximate the solution to the equation in the mathematical expression:
wherein
Representing the solved equation solution in the iteration process, and superscripts k and i represent the iteration times and the ith equation respectively. W i 、p i Respectively representing the ith row and projection of the coefficient matrix W
The ith element of (1). Lambda [ alpha ] ART Is a relaxation factor that controls the convergence speed and convergence of the iteration.
S534: calculating optical sensitivity constants of the second signal detection system and the third signal detection system respectively by combining the flame radiation signal and the radiation signal of the wide-spectrum standard light source which are respectively collected by the second signal detection system and the third signal detection system and the transmissivity curves of the first waveband optical filter 12 and the second waveband optical filter 15;
s535: obtaining time-resolved three-dimensional combustion field temperature based on Planck's radiation law through optical sensitivity constants and three-dimensional relative radiation signal distribution under the first and second wave bands obtained by reconstruction, namely obtaining turbulent combustion field four-dimensional temperature distribution:
according to planck's law of radiation, the intensity of the object radiation I (λ, T) is a function of the wavelength λ, the emissivity e (λ), and the temperature T:
by adopting a colorimetric thermometry method, the radiation intensities under two different wavelengths are subjected to ratio, and the following formula is obtained by combining Rayleigh approximation:
wherein m is the complex refractive index, and E (m) is the refractive function. When the values of the refraction functions under different wavelengths are determined and the ratio of the radiation intensities can be measured, the temperature can be calculated according to the formula. The radiation intensity ratio is obtained by the optical sensitivity constants of the two high-speed cameras in S534 and the three-dimensional relative radiation signal distribution of the reconstructed region to be measured in S533 under two different wavebands. Therefore, the three-dimensional temperature distribution of the region to be measured can be determined by the table look-up method.
Preferably, step S55 further includes, but is not limited to, the steps of:
s551: according to laser-induced incandescent light signals excited by different laser pulses in multiple angles and respectively measured by the fourth signal detection system and the fifth signal detection system in the S531, establishing an inversion model of a laser-induced incandescent light signal field by adopting a Monte Carlo ray tracing method and respectively combining the fourth signal detection system and the fifth signal detection system obtained in the calibration process and the position relation among a plurality of detection angles in the fourth signal detection system and the fifth signal detection system;
s552: solving an inversion problem by adopting an algebraic reconstruction method in combination with an inversion model of the laser-induced incandescent light signal field, and reconstructing a first four-dimensional laser-induced incandescent light signal field and a second four-dimensional laser-induced incandescent light signal field, which correspond to a fourth signal detection system and a fifth signal detection system respectively and are detected by a combustion field area to be detected under each laser pulse excitation in a third wave band;
s553: neglecting attenuation along the laser propagation direction, correcting the first four-dimensional laser-induced incandescent light signal field and the second four-dimensional laser-induced incandescent light signal field which are obtained by reconstruction in the S552 based on the high-frequency laser pulse real-time line type measured by the first signal detection system in the S531, and correcting the influence of uneven laser light intensity distribution on the measurement signal;
s554: fitting to obtain a laser-induced incandescent light signal attenuation curve corresponding to each laser pulse according to the first four-dimensional laser-induced incandescent light signal field and the second four-dimensional laser-induced incandescent light signal field which are obtained in S553 and have a certain time delay;
s555: and fitting to obtain three-dimensional carbon smoke particle primary particle size distribution corresponding to each laser pulse based on the laser-induced incandescent light model by combining the laser-induced incandescent light signal attenuation curves corresponding to different laser pulses obtained in the S534, so as to obtain the three-dimensional carbon smoke particle primary particle size distribution analyzed by the turbulent combustion field time.
Further, the laser-induced incandescent light model in step S555 is established based on the energy conservation equation, and the mathematical expression thereof is:
change of energy by absorption
Heat conduction
(obtained by S53 described above depending on the bath temperature), sublimation
Leading to. Wherein d is p Is the soot particle size to be measured,
the decay rate of the LII decay curve can be fitted as described above in S554. Therefore, the soot particle diameter d can be solved through an energy conservation equation p 。
The present embodiment is only for explaining the present invention, and it is not limited to the present invention, and those skilled in the art can make modifications of the present embodiment without inventive contribution as needed after reading the present specification, but all of them are protected by patent law within the scope of the claims of the present invention.
Claims (9)
1. A turbulent combustion field four-dimensional soot particle primary particle size distribution measuring method is characterized by comprising the following steps:
s1, building a laser light path system, installing a high-frequency laser, installing an optical component along the light path, a burner to be tested positioned in the laser light path, and a first signal detection system for recording the light intensity distribution of the laser in real time;
s2, establishing a colorimetric radiation temperature measurement system based on endoscopic chromatography, uniformly distributing a plurality of incident ends of a first one-by-one multi-endoscope at the same side of the same radius circumference outside a combustor to be measured, aligning the incident end of a first spectroscope to the emergent end of the first one-by-one multi-endoscope, and respectively aligning a second signal detection system and a third signal detection system to two emergent ends of the first spectroscope;
s3, establishing a laser-induced incandescent light signal measuring system based on endoscopic chromatography, and uniformly distributing a plurality of incident ends of a second one-in-many endoscope to the same side of the same radius circumference outside the combustor to be measured; the incident end of the second spectroscope is aligned to the emergent end of the second multi-splitting endoscope, and the fourth signal detection system and the fifth signal detection system are respectively aligned to the two emergent ends of the second spectroscope;
s4, setting and triggering a colorimetric radiation temperature measurement system and a laser-induced incandescent light signal measurement system through a signal generator; the signal generator is used for setting a first signal detection system to synchronously trigger with a second signal detection system and a third signal detection system, setting a fourth signal detection system to delay for triggering, and setting a certain delay between a fifth signal detection system and the first signal detection system as well as the fourth signal detection system;
s5, respectively acquiring and processing multi-angle signals by a first signal detection system, a second signal detection system, a third signal detection system, a fourth signal detection system and a fifth signal detection system to obtain four-dimensional distribution of combustion field temperature distribution and primary particle size of soot particles;
s51: calibrating each detection angle position in a colorimetric radiation temperature measurement system based on endoscopic chromatography and a laser-induced incandescent light signal measurement system based on endoscopic chromatography;
s52: when the combustor 6 to be tested does not work, the wide-spectrum standard light source with known absolute radiation intensity under different wavelengths is placed at the central position on the combustor 6 to be tested, the radiation signals of the wide-spectrum standard light source are respectively collected by a second signal detection system and a third signal detection system, and the calibration of the radiation signal intensity in the colorimetric radiation temperature measurement system based on the endoscopic chromatography is completed;
s53: carrying out data processing on a colorimetric radiation temperature measurement system based on endoscopic chromatography to obtain four-dimensional temperature distribution of a turbulent combustion field;
s54: correcting laser-induced incandescent light signals detected by a fourth signal detection system and a fifth signal detection system in the laser-induced incandescent light signal measurement system based on endoscopic chromatography according to the real-time laser line type detected by the first signal detection system, and reducing the influence of uneven laser intensity distribution on a detected result;
s55: and (3) carrying out data processing on the laser-induced incandescent light signal measurement system based on endoscopic chromatography to obtain the primary particle size distribution of the four-dimensional carbon smoke particles in the turbulent combustion field.
2. The turbulent combustion field four-dimensional soot particle primary particle size distribution measuring method as claimed in claim 1, wherein the establishment of the laser light path is specifically as follows:
a spherical concave lens, a first cylindrical convex lens, a second cylindrical convex lens, a reflector, a combustor to be tested and a neutral density attenuation sheet are sequentially arranged along a light path of a laser beam emitted by the high-frequency laser; the first signal detection system collects and detects laser signals, and the neutral density attenuation sheet is positioned between the combustor to be detected and the first signal detection system;
the first cylindrical convex lens and the second cylindrical convex lens respectively expand the laser beam in width and height; the distance between the first cylindrical convex lens and the spherical concave lens is the difference between the absolute values of the focal lengths of the first cylindrical convex lens and the spherical concave lens; the distance between the second cylindrical convex lens and the spherical concave lens is the difference of the absolute focal length values of the second cylindrical convex lens and the spherical concave lens.
3. The turbulent combustion field four-dimensional soot particle primary particle size distribution measuring method as claimed in claim 1, characterized by:
the first signal detection system sequentially comprises a first lens and a first high-speed camera along a light path; the second signal detection system comprises a first waveband optical filter, a second lens and a second high-speed camera which are sequentially connected; the third signal detection system comprises a second waveband optical filter, a third lens and a third high-speed camera which are sequentially connected; the fourth signal detection system comprises a first third band filter, a fourth lens, a first image intensifier and a fourth high-speed camera which are sequentially connected; the fifth signal detection system comprises a second third band filter, a fifth lens, a second image intensifier and a fifth high-speed camera which are sequentially connected;
a sixth lens is arranged in front of each incident end of the first one-to-many endoscope; and seventh lenses are respectively arranged in front of the incident ends of the second one-in-multiple endoscope.
4. A turbulent combustion field four-dimensional soot particle primary particle size distribution measuring method as claimed in claim 3, characterized by: the light-emitting wavelength of the wide-spectrum standard light source comprises the band-pass intervals of the first band-pass filter and the second band-pass filter.
5. A turbulent combustion field four-dimensional soot particle primary particle size distribution measuring method as claimed in claim 4, wherein the calibration of step S51 specifically includes:
s511, placing a black and white lattice calibration plate with a known lattice size at the central position of a combustor to be tested, adjusting the position of the calibration plate, simultaneously acquiring black and white lattice images on the calibration plate from a plurality of angles in a first one-to-many endoscope and a second one-to-many endoscope respectively, and recording and storing the black and white lattice images through a second signal detection system, a third signal detection system, a fourth signal detection system and a fifth signal detection system respectively;
s512, respectively extracting intersection points of black and white grids in calibration board images of different angles, which are simultaneously shot in each signal detection system, according to calibration board data detected by the second signal detection system, the third signal detection system, the fourth signal detection system and the fifth signal detection system, and obtaining coordinates of the intersection points under each camera coordinate system and the world coordinate system in different signal detection systems;
s513, obtaining the needed calibration parameters by combining the coordinates of the grid intersection points in different camera coordinate systems and world coordinate systems and a calibration algorithm, and determining the position relationship between the second signal detection system, the third signal detection system, the fourth signal detection system, the fifth signal detection system and the combustion field area to be detected and the relative position relationship between different detection angles in each signal detection system according to the calibration parameters.
6. A turbulent combustion field four-dimensional soot particle primary particle size distribution measuring method as claimed in claim 5, wherein the step S53 specifically includes:
s531: enabling the combustor to be tested to work under a turbulent flow working condition and a high-frequency laser to work, triggering each signal detection system through a signal generator according to the setting, and recording and storing data acquired by each signal detection system;
s532: establishing an inversion model of a radiation signal field by adopting a Monte Carlo ray tracing method and respectively combining a second signal detection system, a third signal detection system and the position relation among a plurality of detection angles obtained in the calibration process;
s533: solving an inversion problem by combining an inversion model of a radiation signal field and adopting an algebraic reconstruction method, and reconstructing three-dimensional relative radiation signal distribution of the combustion field area to be measured under a first wave band and a second wave band respectively;
s534: calculating optical sensitivity constants of the second signal detection system and the third signal detection system respectively by combining the flame radiation signal and the radiation signal of the wide-spectrum standard light source which are respectively collected by the second signal detection system and the third signal detection system and the transmissivity curves of the first waveband optical filter and the second waveband optical filter;
s535: and obtaining time-resolved three-dimensional combustion field temperature based on the Planck's radiation law through the optical sensitivity constant and the three-dimensional relative radiation signal distribution under the first wave band and the second wave band obtained through reconstruction, and obtaining the four-dimensional temperature distribution of the turbulent combustion field.
7. A turbulent combustion field four-dimensional soot particle primary particle size distribution measuring method as claimed in claim 6, wherein the step S55 specifically includes:
s551, according to the measured laser-induced incandescent light signals excited by different laser pulses in multiple angles, establishing an inversion model of a laser-induced incandescent light signal field by adopting a Monte Carlo ray tracing method and respectively combining the position relations among a plurality of detection angles in a fourth signal detection system and a fifth signal detection system obtained in a calibration process;
s552, combining an inversion model of the laser-induced incandescent light signal field, solving an inversion problem by adopting an algebraic reconstruction method, and reconstructing a first four-dimensional laser-induced incandescent light signal field and a second four-dimensional laser-induced incandescent light signal field, which correspond to a fourth signal detection system and a fifth signal detection system respectively and are detected by a combustion field area to be detected under each laser pulse laser in a third wave band;
s553, neglecting attenuation along the laser propagation direction, correcting the reconstructed first four-dimensional laser-induced incandescent light signal field and the reconstructed second four-dimensional laser-induced incandescent light signal field based on the high-frequency laser pulse real-time line type measured by the first signal detection system, and correcting the influence of uneven laser light intensity distribution on the measurement signal;
s554, fitting the obtained first four-dimensional laser-induced incandescent light signal field and the obtained second four-dimensional laser-induced incandescent light signal field with a certain time delay to obtain a laser-induced incandescent light signal attenuation curve corresponding to each laser pulse;
and S555, combining the obtained laser-induced incandescent light signal attenuation curves corresponding to different laser pulses, and fitting to obtain three-dimensional carbon smoke particle primary particle size distribution corresponding to each laser pulse based on the laser-induced incandescent light model, so as to obtain the three-dimensional carbon smoke particle primary particle size distribution analyzed by turbulent combustion field time.
8. The turbulent combustion field four-dimensional soot particle primary particle size distribution measuring method as claimed in claim 1, wherein: the light splitting ratio of the first light splitting mirror is 1: 1; the splitting ratio of the second beam splitter is 3: 7.
9. a turbulent combustion field four-dimensional soot particle primary particle size distribution measuring system is characterized in that: the device comprises a laser optical path system, a colorimetric radiation temperature measurement system based on endoscopic chromatography, a laser-induced incandescent light signal measurement system based on endoscopic chromatography, and a signal generator for signal triggering;
the laser optical path system comprises a high-frequency laser for emitting laser beams, a spherical concave lens, a first cylindrical convex lens, a second cylindrical convex lens, a reflector, a combustor to be tested, a neutral density attenuation sheet and a first signal detection system for collecting and detecting laser signals in real time, wherein the spherical concave lens, the first cylindrical convex lens, the second cylindrical convex lens, the reflector, the combustor to be tested and the neutral density attenuation sheet are sequentially arranged along the laser beams;
the colorimetric radiation temperature measuring system comprises a first multi-splitting endoscope, a first spectroscope, a second signal detection system and a third signal detection system; the first one-to-many endoscope comprises a plurality of incident ends which are uniformly distributed on the circumference of the same radius at the same side outside the combustor to be tested; the first spectroscope is aligned with the emergent end of the first one-to-many endoscope; the incident ends of the second signal detection system and the third signal detection system are respectively aligned to the two emergent ends of the first spectroscope;
the laser-induced incandescent light signal measuring system comprises a second multi-split endoscope, a second spectroscope, a fourth signal detection system and a fifth signal detection system; the second one-to-many endoscope comprises a plurality of incident ends which are uniformly distributed on the circumference of the same radius at the same side outside the combustor to be tested; the second spectroscope is aligned with the emergent end of the second multi-split endoscope; the incident ends of the fourth signal detection system and the fifth signal detection system are respectively aligned to the two emergent ends of the second spectroscope;
the signal generator is provided with a trigger signal, a first signal detection system, a second signal detection system and a third signal detection system are synchronously triggered, the fourth signal detection system and the first signal detection system are triggered in a delayed mode, and the fifth signal detection system and the fourth signal detection system are triggered in a delayed mode; and the time delay between the fifth signal detection system and the first signal detection system and the time delay between the fifth signal detection system and the fourth signal detection system are all in nanosecond level.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110584029.9A CN113310857B (en) | 2021-05-27 | 2021-05-27 | Turbulent combustion field four-dimensional carbon smoke particle primary particle size distribution measuring system and method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110584029.9A CN113310857B (en) | 2021-05-27 | 2021-05-27 | Turbulent combustion field four-dimensional carbon smoke particle primary particle size distribution measuring system and method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113310857A CN113310857A (en) | 2021-08-27 |
| CN113310857B true CN113310857B (en) | 2022-08-09 |
Family
ID=77375529
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110584029.9A Active CN113310857B (en) | 2021-05-27 | 2021-05-27 | Turbulent combustion field four-dimensional carbon smoke particle primary particle size distribution measuring system and method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113310857B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN118090616A (en) * | 2024-04-18 | 2024-05-28 | 中国空气动力研究与发展中心设备设计与测试技术研究所 | Complex combustion field carbon smoke concentration measurement system and application method thereof |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US10596387B2 (en) * | 2007-04-08 | 2020-03-24 | Immunolight, Llc. | Tumor imaging with X-rays and other high energy sources using as contrast agents photon-emitting phosphors having therapeutic properties |
| CN107976384B (en) * | 2017-10-20 | 2019-07-09 | 浙江大学 | One-wavelength laser induces incandescence nano-scale carbon soot calipers and method |
| CN109990834A (en) * | 2019-03-27 | 2019-07-09 | 东南大学 | High-temperature flight particle temperature, speed, partial size in-situ measuring method |
| CN111257497A (en) * | 2020-02-17 | 2020-06-09 | 上海交通大学 | Flame temperature field measuring device and method |
-
2021
- 2021-05-27 CN CN202110584029.9A patent/CN113310857B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN113310857A (en) | 2021-08-27 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Legros et al. | Simultaneous soot temperature and volume fraction measurements in axis-symmetric flames by a two-dimensional modulated absorption/emission technique | |
| CN110823849B (en) | Quantitative measurement method and device for transient combustion field | |
| US6154277A (en) | Absolute intensity measurements in laser induced incandescence | |
| Wang et al. | Two-dimensional tomography for gas concentration and temperature distributions based on tunable diode laser absorption spectroscopy | |
| Ren et al. | Machine learning applied to retrieval of temperature and concentration distributions from infrared emission measurements | |
| Boïarciuc et al. | Soot volume fractions and primary particle size estimate by means of the simultaneous two-color-time-resolved and 2D laser-induced incandescence | |
| Lou et al. | Review of soot measurement in hydrocarbon-air flames | |
| CN111257497A (en) | Flame temperature field measuring device and method | |
| CN108627478B (en) | Extinction method and radiant light combined carbon smoke measuring device in steady-state flame | |
| CN112082672B (en) | Three-dimensional combustion field temperature measuring method based on extinction correction time analysis | |
| CN106815878A (en) | A kind of image rebuilding method based on the multispectral tomography of various visual angles | |
| JPH06323996A (en) | Method for obtaining characterstic of radical forming process | |
| CN107144503A (en) | Liquid fuel spray burning drop and flame synchronous measuring apparatus and method | |
| CN111855628B (en) | Method for measuring flame three-dimensional structure of transient combustion field by endoscopic chromatography and volume laser induced fluorescence imaging | |
| US9459216B2 (en) | Method for characterizing flame and spray structures in windowless chambers | |
| CN113310857B (en) | Turbulent combustion field four-dimensional carbon smoke particle primary particle size distribution measuring system and method thereof | |
| Goschütz et al. | Endoscopic imaging of early flame propagation in a near-production engine | |
| US6734965B2 (en) | Optical patternation method | |
| CN114608701A (en) | Non-contact measurement system and method for three-dimensional spatial distribution of laser intensity | |
| Yuan et al. | Influence analysis of radiative properties and flame temperature reconstruction based on optical tomography | |
| Qi et al. | Simultaneous reconstruction of flame temperature and soot volume fraction through weighted non-negative least squares and light field imaging techniques | |
| CN109974893B (en) | Gradient refractive index flame three-dimensional temperature field measuring method | |
| Jiang et al. | Visual flame monitoring system based on two-color method | |
| CN115112016B (en) | Three-dimensional size detection method for surface defects of optical element | |
| CN115639124A (en) | Device and method for realizing soot concentration measurement and in-situ calibration by using single-wavelength laser |
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 |