CN112629670A - High-frequency dynamic flame temperature measuring method and system - Google Patents
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Abstract
The invention relates to a high-frequency dynamic flame temperature measuring method and a high-frequency dynamic flame temperature measuring system. The method adopts two seed lasers with different wavelengths and injects the seed lasers into a solid laser through an optical fiber coupler to amplify the energy; the laser wavelength injected is rapidly switched through the optical switch, laser pulses with rapidly switched wavelengths are obtained, and double-pulse laser imaging is carried out through the same camera. The time sequence parameters such as the delay and the pulse width of the pulse signal are provided by a time delay generator with the time precision reaching picosecond level, and the synchronous capture and interference elimination functions of the two-dimensional temperature field laser induced fluorescence signal are realized through the time sequence coordination between the optical switch and the imaging system. Compared with the traditional double-line temperature measurement method adopting two sets of imaging with different wavelengths, the method has the advantages of high imaging quality of a single camera, simple control system, simple light path arrangement and the like.
Description
Technical Field
The invention relates to a flame temperature measuring technology, in particular to a high-frequency dynamic flame temperature measuring method and system.
Background
The gas turbine is an important device for heat-work conversion and is a main means for realizing low-pollution combustion. The research on the combustion mechanism of the gas turbine has important significance for improving the combustion efficiency and reducing the pollutant emission, and the temperature is a key parameter in the combustion process. The research and the improvement of the flame temperature measurement technology have important practical values in theoretical research of reaction mechanism in the combustion process, development of novel low-pollution machine types and research of the working stability of the gas turbine.
In recent years, the scheme of applying PLIF technology to combustion field temperature measurement is mainly a two-line PLIF temperature measurement method, and the PLIF technology can obtain two-dimensional imaging of some groups (CH2O, NO, CH, OH) and the like in a combustion field, so that temperature field measurement with space-time resolution can be realized, and the influence of pressure, free radical concentration and fluorescence quenching effect can be avoided theoretically. The principle of the method is that two beams of laser with different wavelengths are used for almost simultaneously exciting a certain group to be at different rotation energy levels of the same vibration energy level, the flame temperature can be obtained by calculating the ratio of corresponding fluorescent signals, and the two-dimensional whole field temperature can be obtained by performing fluorescent signal-temperature conversion on each pixel point. The formula of the double-line PLIF temperature measurement method is as follows:
wherein, Delta E12The energy level interval between two excited rotation energy levels 1 and 2 at the lower energy level; k is Boltzmann constant; r is the ratio of the two energy levels to the fluorescent signal; i is1And I2Respectively, corresponding to the excitation wavelengths of the two rotation levels. Therefore, only PLIF images and laser energy signals of two different excitation lines can be measured to process and obtain two-position temperature field distribution in the flame.
The traditional two-line PLIF temperature measurement generally adopts two schemes to realize the process, the first scheme is to adopt two lasers with different wavelengths to ensure that the wavelengths are respectively fixed at the absorption peak positions of two rotating energy levels of a group so as to realize the fluorescence signal measurement in a short time interval, but the process has the problems of difficult light path coupling, difficult adjustment of experimental states of a plurality of instruments and complex control system of a dual-wavelength laser; the second scheme is to use a tunable laser to perform fast wavelength scanning, so as to realize wavelength switching of two peak positions in a short time, and the problem in the process is that the wavelength switching can not be completed in a very short time, so that the double-peak synchronous measurement can not be completed, and the measurement of a highly turbulent temperature field with extremely fast state change can not be realized.
Disclosure of Invention
The present invention is directed to a method and system for measuring a high frequency dynamic flame temperature to solve the above problems. Therefore, the technical scheme adopted by the invention is as follows:
according to an aspect of the present invention, there is provided a high-frequency dynamic flame temperature measuring system, which may include first and second seed laser generators, first and second acousto-optic modulation modules, a first digital delay signal generator, an optical fiber coupler, a light intensity measuring device, a solid laser, a point-to-surface light path converting assembly, a high-speed camera, an image intensifier, and a computer, the first and second seed laser generators being respectively configured to generate first and second seed lasers and being respectively connected to inlets of the first and second acousto-optic modulation modules through respective optical fibers, the first digital delay signal generator being configured to on-off control the first and second acousto-optic modulation modules, outlets of the first and second acousto-optic modulation modules being connected to the optical fiber coupler through respective optical fibers, the optical fiber coupler is connected to an inlet of the solid laser through an outlet optical fiber, the solid laser is used for frequency doubling, modulating and amplifying laser output by the optical fiber coupler into a double-pulse laser signal with the total frequency of 40KHZ, the light intensity measuring device is arranged near a light outlet of the solid laser and is electrically connected with the computer and used for measuring the light intensity of the double-pulse laser signal, and the point-surface optical path conversion component is arranged at the light outlet accessory of the solid laser and used for converting point-shaped double-pulse laser into plane double-pulse laser so as to induce a fluorescent signal from flame; the high-speed camera and the point-surface light path conversion component are respectively arranged on two sides of the flame to be detected and positioned on a flame central plane; the high-speed camera is used for shooting fluorescent signals, the high-speed camera and the image intensifier are electrically connected with the computer, and the computer is used for calculating and obtaining two-dimensional temperature field distribution of flame according to light intensity information and plane laser induced fluorescent signals.
In a preferred embodiment, the wavelengths of the first seed laser and the second seed laser are 1064.1nm and 1064.2nm, respectively.
In a preferred embodiment, the first seed laser generator and the second seed laser generator have respective controllers for varying the control temperature and control current of the seed laser to obtain a desired wavelength of seed laser light.
In a preferred embodiment, the first acousto-optic modulation module and the second acousto-optic modulation module are acousto-optic modulators.
In a preferred embodiment, the first digital delay generator has an AB outlet and a CD outlet, and the AB outlet and the CD outlet are electrically connected to the first acousto-optic modulation module and the second acousto-optic modulation module, respectively.
In a preferred embodiment, the fixed laser is Nd: YAG high-frequency pulse laser, and comprises a third acousto-optic modulation module, a fourth acousto-optic modulation module, an optical fiber amplifier and a second digital time delay signal generator, the optical fiber coupler is connected to the third acousto-optic modulation module through an outlet optical fiber, the third acousto-optic modulation module is connected to the fourth acousto-optic modulation module, the fourth acousto-optic modulation module is connected to the optical fiber amplifier, the second digital delay signal generator is used for controlling the on-off of the third acousto-optic modulation module and the fourth acousto-optic modulation module, so as to modulate the pulse signals of the first seed laser and the second seed laser again to generate a double-pulse laser signal with the total frequency of 40KHZ, the double-pulse laser signal passes through the Nd: YAG high frequency pulse laser is processed by crystal frequency doubling and optical parametric amplifier to become laser capable of exciting free radical fluorescence signal; the optical fiber amplifier is used for amplifying the double-pulse laser signal and improving the energy of the double-pulse laser signal.
In a preferred embodiment, one path of signal of the second digital delay signal generator is output to the high-speed camera as a shooting trigger signal, the SYNC signal is output to the high-speed camera as a shutter signal, and the high-speed camera outputs one path of signal to the image intensifier, so that the trigger signals of the two are synchronous with the shutter signal, and the double-pulse laser signal is enveloped in the shutter time of the image intensifier and the shutter time of the high-speed camera.
In a preferred embodiment, the light intensity measuring device includes a photodiode detector, an oscilloscope and a data acquisition card, the photodiode detector is disposed near the light outlet of the optical fiber amplifier and is used for detecting a light intensity signal, a signal output port of the photodiode detector is connected to a sampling channel of the oscilloscope, and the data acquisition card is used for acquiring the light intensity signal on the oscilloscope after each pulse in real time and transmitting the light intensity signal to the computer.
In a preferred embodiment, the system further comprises an 226/283/355nm filter arranged between the light outlet of the Nd: YAG high-frequency pulse laser and the point-to-surface optical path conversion component assembly.
According to another aspect of the present invention, there is also provided a high frequency dynamic flame temperature measurement method, which may include the steps of:
providing a high frequency dynamic flame temperature measurement system as described above;
shooting and signal acquisition processing are carried out on the standard plane diffusion flame, and correlation information of pixel point light intensity information and a temperature field is obtained and is used as calibration data;
keeping the parameters of the optical fiber amplifier and the image intensifier unchanged, shooting the turbulent flame with high-speed pulsation, and combining fluorescence information, laser light intensity information and calibration data to obtain the temperature field distribution information of the high-speed turbulence.
Further, the method comprises the steps of: the control temperature and control current of the first seed laser generator and the second seed laser generator are adjusted to generate 1064.1nm of the first seed laser and 1064.2nm of the second seed laser.
The invention adopts the acousto-optic modulation module to rapidly switch the wavelength, simplifies the system arrangement structure, solves the problem of complex optical path coupling of a plurality of lasers, and adopts the 40KHz ultrahigh frequency pulse laser to realize rapid and dynamic temperature measurement of a turbulent flow field.
Drawings
FIG. 1 is a schematic view of a high frequency dynamic flame temperature measurement system of the present invention;
FIG. 2 is a schematic diagram of the coupling of the high-speed camera gate signal, the image intensifier switch signal and the double-pulse laser signal after adjusting the timing sequence;
fig. 3 is a turbulent combustion transient temperature field distribution diagram experimentally obtained by using the high frequency dynamic flame temperature measurement system and method of the present invention, wherein a-f show turbulent combustion transient temperature field distributions with times t of 0, 50 μ s, 100 μ s, 400 μ s, 900 μ s and 1ms, respectively.
Reference numerals: 1. the device comprises a first seed laser generator, a second seed laser generator, a first acousto-optic modulation module, a second acousto-optic modulation module, a 5, a first digital delay signal generator, a 6, an optical fiber coupler, a 7, Nd, a YAG high-frequency pulse laser, a 71, a third acousto-optic modulation module, a 72, a fourth acousto-optic modulation module, a 73, an optical fiber amplifier, a 74, a second digital delay signal generator, a 8, a light intensity measuring device (a photodiode detector), a 9, a point-to-surface optical path conversion component, a 10, a high-speed camera, a 11, an image intensifier, a 12 and a computer.
Detailed Description
The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings in order to more clearly understand the objects, features and advantages of the present invention. It should be understood that the embodiments shown in the drawings are not intended to limit the scope of the present invention, but are merely intended to illustrate the spirit of the technical solution of the present invention.
As shown in fig. 1, a high-frequency dynamic flame temperature measuring system may include a first seed laser generator 1, a second seed laser generator 2, a first acousto-optic modulation module 3, a second acousto-optic modulation module 4, a first digital delay signal generator 5, an optical fiber coupler 6, a solid laser 7, a light intensity measuring device 8, a point-to-plane optical path conversion component 9, a high-speed camera 10, an image intensifier 11, a computer 12, and the like. The first seed laser generator 1 and the second seed laser generator 2 are conventional lasers for generating a first seed laser of 1064.1nm and a second seed laser of 1064.2nm, respectively. The first seed laser generator 1 and the second seed laser generator 2 are connected with the corresponding controllers, and the control temperature and the control current of the first seed laser generator 1 and the second seed laser generator 2 can be changed by changing two parameters of the temperature and the current of the controllers, so that seed laser with required wavelength is obtained.
The first seed laser 1 and the second seed laser 2 are respectively connected with inlets of the first acousto-optic modulation module 3 and the second acousto-optic modulation module 4 through corresponding optical fibers, so that the first seed laser and the second seed laser can respectively enter the first acousto-optic modulation module 3 and the second acousto-optic modulation module 4. The first acousto-optic modulation module 3 and the second acousto-optic modulation module 4 are commercially available acousto-optic modulators, such as model number FT-OAM-AOM-O1 available from F-tone Networks.
The time accuracy of the first digital delay signal generator 5 can reach picosecond level, and the first digital delay signal generator is provided with two groups of signal output ports of AB and CD. The first digital delay signal generator outputs high and low level signals through two groups of signal output ports of the AB and CD to perform on-off control on the first acousto-optic modulation module 3 and the second acousto-optic modulation module 4, and further performs time sequence control such as delay time, pulse width length and the like on the first seed laser and the second seed laser, so that the first seed laser and the second seed laser of continuous signals are cut into pulse signals.
The outlets of the first acousto-optic modulation module 3 and the second acousto-optic modulation module 4 are connected to the optical fiber coupler 6 through corresponding optical fibers, so that two paths of pulse signals (the first seed laser and the second seed laser) are coupled together. The fiber coupler 5 is then connected to the inlet of the stationary laser 7 via an outlet fiber. Specifically, the fixed laser 7 may be a commercially available Nd: YAG high frequency pulse laser 7, which may include a third acousto-optic modulation module 71, a fourth acousto-optic modulation module 72, an optical fiber amplifier 73, a second digital delay signal generator 74, and the like, the optical fiber coupler 6 is connected to the third acousto-optic modulation module 71 through an outlet optical fiber, the third acousto-optic modulation module 71 is connected to the fourth acousto-optic modulation module 72, the fourth acousto-optic modulation module 72 is connected to the optical fiber amplifier 73, and the second digital delay signal generator 74 controls the third acousto-optic modulation module 71 and the fourth acousto-optic modulation module 72 to be turned on and off again to modulate the pulse signals of the first seed laser and the second seed laser, thereby generating a double pulse laser signal with a total frequency of 40 KHZ. The double-pulse laser signal is processed by a Nd: YAG high-frequency pulse laser 7 through crystal frequency multiplication and an optical parametric amplifier to become laser (for example, ultraviolet laser with the wavelength of 226/283/355nm and the like) which can be used for exciting a free radical fluorescence signal. In the illustrated embodiment, a Nd: YAG high-frequency pulse laser 7 frequency-multiplies the double-pulse laser signals having wavelengths of 1064.1nm and 1064.2nm into double-pulse laser signals having wavelengths of 354.794nm and 354.805 nm. The fiber amplifier 73 is used to amplify the double-pulse laser signal to increase its energy, so as to ensure sufficient induced fluorescence signal intensity.
The light intensity measuring device 8 is disposed in the vicinity of the light exit of the Nd: YAG high frequency pulse laser 7 (specifically, the fiber amplifier 73) and electrically connected to the computer 12, and measures the light intensity of the double pulse laser signal output from the Nd: YAG high frequency pulse laser 7. Specifically, the light intensity measuring device 8 may include a photodiode detector 8, an oscilloscope (not shown), a data acquisition card (not shown), and the like, wherein the photodiode detector 8 is disposed near a light outlet of the Nd: YAG high-frequency pulse laser 7 (specifically, the optical fiber amplifier 73) for detecting a light intensity signal, a signal output port thereof is connected to a sampling channel of the oscilloscope, and the data acquisition card is used to acquire the light intensity signal on the oscilloscope after each pulse in real time and transmit the light intensity signal to the computer 12. The data acquisition card may be integrated in the computer 12. Alternatively, the light intensity measuring device 8 is a digital light intensity meter directly, and the light intensity may be transmitted to the computer 12 in the form of a digital signal.
The point-surface light path conversion component 9 is arranged near the light outlet of the Nd: YAG high-frequency pulse laser 7 and is used for converting point-shaped double-pulse laser into plane double-pulse laser so as to lead the flame to induce a fluorescence signal. The structure of the point-to-area optical path conversion module 9 is well known and will not be described here. In order to improve the signal-to-noise ratio of the induced fluorescence signal, a 355nm filter is usually disposed between the light exit of the Nd: YAG high-frequency pulse laser 7 and the point-to-area optical path conversion element 9. 355nm is a wavelength value suitable for formaldehyde in a flame to generate a Laser Induced Fluorescence (LIF) signal.
It should be understood that the wavelengths of the first seed laser and the second seed laser are not limited to 1064.1nm and 1064.2nm, which may be set according to practical applications. Accordingly, the wavelength of the double-pulse laser light output from the fixed laser 7 is not limited to about 355nm (354.794nm and 354.805nm), and may be ultraviolet laser light of 226nm, 283nm, or the like.
The high-speed camera 10 is arranged on the other side of the flame temperature to be measured (i.e., the side opposite to the point-to-plane optical path conversion assembly 9), on the flame center plane. YAG high frequency pulse laser 7 second digital delay signal generator 74 output a signal to the high speed camera 10 as shooting trigger signal, SYNC signal to the high speed camera as gate signal, and the high speed camera output a signal to the image intensifier 11, so that the trigger signal and shutter signal of the two are synchronous, and the double pulse laser signal envelope in the image intensifier 11 shutter and high speed camera 10 shutter time, as shown in FIG. 2. The switch of the pulse laser is controlled, and the laser with the wavelengths corresponding to the two wave crests almost simultaneously triggers the camera and the image intensifier shutter to shoot and record the fluorescent signal, so that the wavelength switching is completed in a very short time, and the double-peak synchronous measurement is completed.
After the fluorescence signals are shot by the high-speed camera 10, ratio processing can be carried out on the fluorescence signals in the two adjacent groups of pictures, and two-dimensional temperature field distribution in a target flame plane can be obtained after inversion is carried out by combining light intensity information. That is, according to the formula
It can be known that only the light intensity signals (I) of two beams of pulse laser need to be obtained1And I2) And the ratio (R) made after the fluorescent signal induced by the corresponding pulse laser, the temperature of each pixel point can be calculated according to the formula.
To avoid the difficulty of determining quantum-scale parameters, the temperature field of a standard planar diffusion flame (coflow) was used as a calibration. The temperature field information of a standard planar diffusion flame is known under certain operating conditions. After the light intensity signal and the image fluorescence signal are collected, the temperature field can be calibrated by comparing the collected light intensity signal and the image fluorescence signal with the known standard temperature. After the calibration is finished, parameters of devices such as a camera and an image intensifier are kept unchanged, high-speed pulsating turbulent flame is shot, and the temperature field distribution information of the high-speed turbulent flow can be obtained by combining fluorescence light intensity information, laser light intensity information and a calibration signal.
Accordingly, in an embodiment of the present invention, there is provided a high frequency dynamic flame temperature measurement method, comprising the steps of:
providing a high frequency dynamic flame temperature measurement system as described above;
adjusting the control temperature and control current of the first seed laser generator 1 and the second seed laser generator 2 to generate 1064.1nm of first seed laser light and 1064.2nm of second seed laser light;
shooting and signal acquisition processing are carried out on the standard plane diffusion flame, and correlation information of pixel point light intensity information and a temperature field is obtained and is used as calibration data;
the parameters of the optical fiber amplifier and the image intensifier are kept unchanged, formaldehyde fluorescence signals and light intensity information of high-speed pulsating turbulent flame are measured, turbulent temperature field change information in a very short time can be captured by means of 40KHz high-frequency laser, and temperature distribution information of each frame (interval of 25 microseconds) can be obtained by combining laminar flow calibration flame information with stable temperature distribution, so that the function of high-frequency turbulent non-invasive temperature measurement is realized.
Fig. 3 shows a turbulent combustion transient temperature field distribution plot obtained by experiments using the high-frequency dynamic flame temperature measurement system and method of the present invention, wherein a-f show turbulent combustion transient temperature field distributions with time t of 0, 50 μ s, 100 μ s, 400 μ s, 900 μ s and 1ms, respectively. Therefore, the method can realize the measurement of microsecond-level flame temperature field information, and can be applied to occasions needing to accurately control the flame temperature.
In conclusion, the method adopts two seed lasers with different wavelengths (1064.1nm and 1064.2nm) and injects the seed lasers into a solid laser through a fiber coupler to amplify the energy; the laser wavelength of the injected laser is rapidly switched through the optical switch (the first to the fourth acousto-optic modulation modules), laser pulses with the rapidly switched wavelength are obtained, and double-pulse laser imaging is carried out through the same camera. The time sequence parameters such as the delay and the pulse width of the pulse signal are provided by a time delay signal generator (namely, a second digital time delay signal generator) with the time precision reaching picosecond level, and the synchronous capture and interference elimination functions of the two-dimensional temperature field laser induced fluorescence signal are realized through the time sequence coordination between the optical switch and the imaging system (the high-speed camera 10 and the image intensifier 11). Compared with the traditional double-line temperature measurement method adopting two sets of imaging with different wavelengths, the double-line temperature measurement method has the advantages of high double-wavelength switching speed, high imaging quality of a single camera, simple control system, simple optical path setting and the like.
While the preferred embodiments of the present invention have been illustrated and described in detail, it should be understood that various changes and modifications of the invention can be effected therein by those skilled in the art after reading the above teachings of the invention. Such equivalents are intended to fall within the scope of the claims appended hereto.
Claims (10)
1. A high-frequency dynamic flame temperature measuring system is characterized by comprising a first seed laser generator, a second seed laser generator, a first acousto-optic modulation module, a second acousto-optic modulation module, a first digital time delay signal generator, an optical fiber coupler, a light intensity measuring device, a solid laser, a point-to-surface light path conversion assembly, a high-speed camera, an image intensifier and a computer, wherein the first seed laser generator and the second seed laser generator are respectively used for generating first seed laser and second seed laser with different wavelengths and are respectively connected with inlets of the first acousto-optic modulation module and the second acousto-optic modulation module through corresponding optical fibers, the first digital time delay signal generator is used for carrying out on-off control on the first acousto-optic modulation module and the second acousto-optic modulation module, outlets of the first acousto-optic modulation module and the second acousto-optic modulation module are connected to the optical fiber coupler through corresponding optical fibers, the optical fiber coupler is connected to an inlet of the solid laser through an outlet optical fiber, the solid laser is used for frequency doubling, modulating and amplifying laser output by the optical fiber coupler into a double-pulse laser signal with the total frequency of 40KHZ, the light intensity measuring device is arranged near a light outlet of the solid laser and is electrically connected with the computer and used for measuring the light intensity of the double-pulse laser signal, and the point-surface optical path conversion component is arranged at the light outlet accessory of the solid laser and used for converting point-shaped double-pulse laser into plane double-pulse laser so as to induce a fluorescent signal from flame; the high-speed camera and the point-surface light path conversion component are respectively arranged on two sides of the flame to be detected and positioned on a flame central plane; the high-speed camera is used for shooting fluorescent signals, the high-speed camera and the image intensifier are electrically connected with the computer, and the computer is used for calculating and obtaining two-dimensional temperature field distribution of flame according to light intensity information and plane laser induced fluorescent signals.
2. The high frequency dynamic flame temperature measurement system of claim 1, wherein the first seed laser and the second seed laser have wavelengths of 1064.1nm and 1064.2nm, respectively.
3. The high frequency dynamic flame temperature measurement system of claim 1 or 2, wherein the first seed laser generator and the second seed laser generator have respective controllers for varying the control temperature and control current of the seed lasers to obtain a desired wavelength of seed laser.
4. The high frequency dynamic flame temperature measurement system of claim 1, wherein the first digital delay generator has an AB outlet and a CD outlet, the AB outlet and CD outlet being electrically connected to the first acousto-optic modulation module and the second acousto-optic modulation module, respectively.
5. The high-frequency dynamic flame temperature measuring system of claim 1, wherein the fixed laser is a Nd: YAG high-frequency pulse laser, and comprises a third acousto-optic modulation module, a fourth acousto-optic modulation module, an optical fiber amplifier and a second digital delay signal generator, the optical fiber coupler is connected to the third acousto-optic modulation module through an outlet optical fiber, the third acousto-optic modulation module is connected to the fourth acousto-optic modulation module, the fourth acousto-optic modulation module is connected to the optical fiber amplifier, the second digital delay signal generator is used for controlling the third acousto-optic modulation module and the fourth acousto-optic modulation module to be switched on and off so as to modulate pulse signals of the first seed laser and the second seed laser again and generate a double-pulse laser signal with a total frequency of 40KHZ, and the double-pulse laser signal becomes capable of being processed by a crystal frequency doubling and an optical parametric amplifier of the Nd: YAG high-frequency pulse laser A laser for exciting a free radical fluorescence signal; the optical fiber amplifier is used for amplifying the double-pulse laser signal and improving the energy of the double-pulse laser signal.
6. The high frequency dynamic flame temperature measurement system of claim 5, wherein a signal from the second digital delay generator is output to the high speed camera as a shooting trigger signal, a SYNC signal is output to the high speed camera as a shutter signal, and the high speed camera outputs a signal to the image intensifier such that the trigger signals of the two are synchronized with the shutter signal, and the double pulse laser signal is enveloped within the shutter time of the image intensifier and the shutter time of the high speed camera.
7. The high-frequency dynamic flame temperature measuring system according to claim 5, further comprising an 226/283/355nm filter disposed between the light exit of the Nd: YAG high-frequency pulse laser and the point-to-area optical path conversion assembly.
8. The high frequency dynamic flame temperature measuring system according to claim 1, wherein the light intensity measuring device comprises a photodiode detector, an oscilloscope and a data acquisition card, the photodiode detector is arranged near the light outlet of the optical fiber amplifier for detecting light intensity signals, the signal output port of the photodiode detector is connected to the sampling channel of the oscilloscope, and the data acquisition card is used for acquiring the light intensity signals on the oscilloscope after each pulse in real time and transmitting the light intensity signals to the computer.
9. A high-frequency dynamic flame temperature measuring method is characterized by comprising the following steps:
providing a high frequency dynamic flame temperature measurement system as claimed in any one of claims 1 to 8;
shooting and signal acquisition processing are carried out on the standard plane diffusion flame, and correlation information of pixel point light intensity information and a temperature field is obtained and is used as calibration data;
keeping the parameters of the optical fiber amplifier and the image intensifier unchanged, shooting the turbulent flame with high-speed pulsation, and combining fluorescence information, laser light intensity information and calibration data to obtain the temperature field distribution information of the high-speed turbulence.
10. The high frequency dynamic flame temperature measurement method of claim 9, further comprising the steps of: the control temperature and control current of the first seed laser generator and the second seed laser generator are adjusted to generate 1064.1nm of the first seed laser and 1064.2nm of the second seed laser.
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