A gas three-dimensional combustion temperature field measurement system and method based on a rotating light path

Abstract

The application discloses a kind of gas three-dimensional combustion temperature field measurement system and method based on rotating light path, it is related to the temperature field measurement technology of TDLAS, to solve the problem of low efficiency and poor real-time when the existing TDLAS technology measures temperature field, the complex algorithm of eliminating ghost point, the system and method are sent signal to two laser controllers by data processing module, control two laser time-sharing work and output different frequency laser, laser beam enters several laser emitters arranged on the installation support that can rotate after being combined, the electrical signal generated by laser receiver during rotation is collected by data acquisition card and input to data processing module, the temperature of each position in the measured field is calculated by data processing module according to the data obtained at different angles of installation support, and ghost point is eliminated.The application eliminates ghost point by mechanical rotation, significantly improves the measurement efficiency, and can be used for real-time detection of the combustion state of marine diesel engine.

Description

Technical Field

[0001] This application relates to diesel engine combustion chambers, specifically to a technique for measuring the flame temperature field at the outlet position of a diesel engine combustion chamber based on TDLAS technology. Background Technology

[0002] As the "heart" of a diesel engine, the combustion chamber's combustion state directly reflects the engine's operating process, exhaust emissions, and combustion efficiency. Monitoring the combustion state allows for the diagnosis of the combustion chamber's current health and prediction of performance trends, ensuring the engine's safe and reliable operation. Therefore, combustion diagnosis of the combustion chamber is essential. The flame temperature within the combustion chamber is a crucial physical quantity. On one hand, the atomization, mixing, and pulsating of fuel within the combustion chamber cause dynamic changes in the combustion flame, resulting in corresponding changes in flame temperature. Monitoring these changes allows for the assessment of the fuel's combustion state. On the other hand, with the development of combustion chambers, the temperature at the combustion chamber outlet has continuously increased, exceeding the melting point of high-temperature alloy materials. Therefore, measuring the flame temperature at the combustion chamber outlet provides important theoretical basis for developing suitable high-temperature alloy materials for combustion chamber construction. Thus, accurate diagnosis of the flame temperature at the combustion chamber outlet is of significant guiding importance for improving combustion efficiency, reducing pollutant emissions, and extending engine lifespan.

[0003] Tunable semiconductor absorption spectroscopy (TDLAS) is a type of laser diagnostic technology, and its principle is as follows: Figure 1 As shown, the laser outputs a specific wavelength of laser light under the control of the signal generator. The laser intensity attenuates after passing through the gas being tested. The attenuated intensity is measured by a detector and calculated by the host computer. The calculation principle is as follows: Based on... Theorem, through the one-to-one correspondence between the spectral absorption rate of monochromatic light and the concentration of the measured gas, the average concentration information of the measured component is calculated. TDLAS has the characteristics of high safety, high sensitivity, high accuracy, fast response speed, etc. At present, the main methods of laser-based temperature measurement include point measurement, integral measurement of optical path length and imaging technology. However, when the measurement target is to provide quantitative, spatial and time-resolved temperature information in actual combustion, these methods have certain limitations, and the temperature measurement method of laser absorption two-dimensional tomography (Tunable Diode Laser Absorption Tomography, TDLAT) combined with computed tomography (Computed Tomography, CT) can overcome this limitation. TDLAT divides the space to be measured into many grids by using the principle of CT, and measures the integral absorbance of TDLAS along the grid lines, and then uses an algorithm to obtain the absorption information at the intersection of the grids, so as to obtain the temperature distribution of the whole field. The dual-line temperature measurement method based on TDLAT has the advantage that the demand for optical devices and computing resources is significantly lower than that of high-spectral tomography, and it has become the mainstream method in the field of TDLAT temperature imaging. However, when reconstructing a two-dimensional / three-dimensional temperature field using this method, if there are multiple high-temperature points in the temperature field, the restored temperature field will have "ghost points" of high-temperature points. "Ghost points" refer to positions with higher calculated temperatures, but they are not actually high-temperature points. The existing technology mostly uses convolutional neural network iterative algorithms or machine vision to filter "ghost points", but the data processing time is long, which affects the speed of real-time online measurement. SUMMARY

[0004] The present application provides a gas three-dimensional combustion temperature field measurement system and method based on a rotating light path to solve or alleviate the above problems.

[0005] The gas three-dimensional combustion temperature field measurement system based on a rotating light path comprises a first laser controller, a second laser controller, a first laser, a second laser, a beam combiner, a beam splitter, a plurality of laser emitters, a plurality of laser receivers, a mounting bracket capable of rotating around its central axis by a preset step length, a support structure capable of extending in the vertical direction, a data acquisition card, and a data processing module; the mounting bracket is fixed on the top of the support structure, and a to-be-measured region is located in the region surrounded by the mounting bracket; the plurality of laser emitters are arranged on the mounting bracket, and the laser emitted by the plurality of laser emitters is located in the plane where the mounting bracket is located; the plurality of laser receivers are arranged on the mounting bracket, and the plurality of laser emitters and the plurality of laser receivers correspond to each other; the data processing module sends control signals to the first laser controller and the second laser controller and receives data collected by the plurality of laser receivers through the data acquisition card; the first laser controller and the second laser controller control the first laser and the second laser respectively according to the received control signals; the laser of different frequencies output by the first laser and the second laser enters the beam combiner and the beam splitter in turn and is divided into a plurality of beams of laser, and the plurality of beams of laser are emitted by the plurality of laser emitters respectively.

[0006] Optionally, the first laser controller and the second laser controller send triangular wave electrical signals to the first laser and the second laser under the control of the data processing module.

[0007] Optionally, the plurality of laser emitters are arranged at equal intervals, and the laser emission directions of the plurality of laser emitters are parallel to each other.

[0008] Optionally, the intersection points formed by the laser emitted by the plurality of laser emitters are uniformly distributed in the to-be-measured region.

[0009] Optionally, the intersection points formed by the laser emitted by the plurality of laser emitters are uniformly distributed in part of the to-be-measured region.

[0010] Optionally, the support structure comprises three telescopic rods, and the three telescopic rods are driven by a motor to realize telescoping.

[0011] Optionally, the support structure comprises three L-shaped support rods and a telescopic rod, the mounting bracket is installed at one end of the three L-shaped support rods, the other end of the three L-shaped support rods is fixed at one end of the telescopic rod, and the telescopic rod is driven by a motor to realize telescoping.

[0012] Optionally, the laser emitters are implemented by using fiber collimators.

[0013] The gas three-dimensional combustion temperature field measurement method based on the system comprises: adjusting the height of the support structure according to a preset first step length; each time the height is adjusted, the mounting bracket is controlled to rotate for one cycle according to a preset second step length, the temperature and the coordinates of each point in the to-be-measured region are calculated according to the data collected by the data acquisition card, and the high-temperature point appearing only once in the rotating process of the mounting bracket is deleted; after the height adjustment of the support structure is completed, the gas three-dimensional combustion temperature field is restored according to the temperature and the coordinates of each point at each height.

[0014] Optionally, the second step length is less than or equal to the angular interval of two adjacent laser emitters.

[0015] The gas three-dimensional combustion temperature field measurement system and method based on the rotating light path of the application can eliminate the "ghost points" by rotating the laser emitters to adjust the laser propagation direction, so that the intersection of the laser propagation path changes constantly, thereby improving the temperature measurement accuracy. The application eliminates the "ghost points" by using mechanical rotation, does not involve iterative algorithms or machine vision technology, avoids a large number of data processing links, can significantly improve the measurement efficiency, and has good real-time performance. The above system and method can realize combustion diagnosis of a marine diesel engine, and can detect the combustion state of the marine diesel engine in real time by restoring the temperature distribution of the three-dimensional field. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 is a schematic diagram of the principle of TDLAS measurement;

[0017] Figure 2 is a schematic diagram of the principle of the gas three-dimensional combustion temperature field measurement system based on the rotating light path according to an embodiment of the application;

[0018] Figure 3 is a schematic diagram of a structure of a mounting bracket according to an embodiment of the application;

[0019] Figure 4 is a schematic diagram of a first arrangement mode of laser emitters and laser receivers according to an embodiment of the application, wherein the arrows represent the laser propagation direction, and part of the laser emitters and part of the laser receivers are not given reference signs;

[0020] Figure 5 is a schematic diagram of a second arrangement mode of laser emitters and laser receivers according to an embodiment of the application, wherein the straight-line arrows represent the laser propagation direction, the arc-shaped arrows represent the rotating direction of the mounting bracket, and part of the laser emitters and part of the laser receivers are not given reference signs;

[0021] Figure 6is a schematic diagram of a third arrangement of laser emitters and laser receivers according to embodiments of the present application, in which straight arrows represent laser propagation directions, and arcuate arrows represent rotation directions of mounting brackets, and in which some laser emitters and some laser receivers are not labeled with reference numerals;

[0022] Figure 7 is a schematic diagram of a three-dimensional combustion temperature field of a reducing gas according to embodiments of the present application. DETAILED DESCRIPTION

[0023] The present application can be implemented or applied in other different embodiments, and various modifications or changes can be made to the details of the application based on different views and applications without departing from the spirit of the application. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0024] As used in this document, the singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise. It will be further understood that the terms "comprises," "comprising," "includes," and / or "including," when used herein, specify the presence of stated features, operations, elements, components, items, and / or groups thereof, but do not preclude the presence or addition of one or more other features, operations, elements, components, items, and / or groups thereof. As used herein, the terms "or" and "and / or" are to be interpreted as inclusive, i.e., as meaning one or any combination of items. Thus, "A, B, or C" or "A, B, and / or C" means any of the following: A; B; C; A and B; A and C; B and C; A, B, and C. An exception to this definition will occur only when a combination of elements, functions, or operations are in some way inherently mutually exclusive.

[0025] In view of the problem of long data processing time and slow real-time online measurement speed when filtering "ghost points" in the existing TDLAS technology-based temperature field reduction method, the present application provides a gas three-dimensional combustion temperature field measurement system and method based on a rotating light path, which can eliminate ghost points during testing and measurement, has small data processing amount, and fast measurement speed.

[0026] Figure 2 is a schematic diagram of a three-dimensional combustion temperature field of a reducing gas according to embodiments of the present application. Figure 2As shown, the system includes a first laser controller 1, a second laser controller 2, a first laser 3, a second laser 4, a beam combiner 5, a beam splitter 6, several laser emitters 7, several laser receivers 8, a mounting bracket 9 capable of rotating in preset steps, a support structure 10 capable of extending and retracting in the vertical direction, a data acquisition card 11, and a data processing module 12. The data processing module 12 can be embedded in a computing device, which can be a computing device such as a computer. The mounting bracket 9 can be a hollow circle or polygon, and the central part of the area enclosed by the mounting bracket 9 is the area to be measured.

[0027] The position of one end of the support structure 10 is fixed, for example, fixed on the experimental table, while the other end of the support structure 10 can extend and retract in the vertical direction.

[0028] In one implementation, the support structure 10 includes a plurality of telescopic rods. Figure 2 For example, the mounting bracket 9 is circular, and the support structure 10 may consist of only three telescopic rods. These three rods are arranged vertically and evenly distributed on the mounting bracket 9. Each telescopic rod is driven by a motor, and the data processing module 12 sends the same control signal to all three motors to control them to extend or shorten by the same length simultaneously. In this implementation, the support structure 10 has a simple structure and low manufacturing cost.

[0029] In another implementation, the support structure 10 includes three L-shaped support rods and one telescopic rod, so as to... Figure 3 For example, the mounting bracket 9 is circular, and the three L-shaped support rods bend in the same direction. The mounting bracket 9 is installed at one end of the three L-shaped support rods, and the other ends of the three L-shaped support rods are fixed to one end of the telescopic rod. The telescopic rod is driven by only one motor. In this implementation, the height of the mounting bracket 9 is adjusted by a single motor. During the adjustment process, the problem of tilting of the mounting bracket 9 caused by inconsistent telescopic lengths of multiple motors can be avoided.

[0030] The mounting bracket 9 is capable of rotating about its own central axis, which refers to the axis passing through the center of the mounting bracket 9 and perpendicular to the plane in which the mounting bracket 9 is located. Specifically, the mounting bracket 9 can be rotated by a motor, which can be controlled by the data processing module 12.

[0031] The laser emitters 7 and the laser receivers 8 are both mounted on the mounting bracket 9, and the laser emitters 7 correspond to the laser receivers 8 one by one. The arrangement of the laser emitters 7 needs to at least meet one of the following two conditions: 1. The transmission paths of the lasers emitted from the respective laser emitters 7 form a series of intersection points; 2. During the rotation of the mounting bracket 9, the propagation paths of the lasers emitted from the respective laser emitters 7 at the current position and the propagation paths of the lasers emitted from the respective laser emitters 7 at the previous position form a series of intersection points.

[0032] There are various arrangements of the laser emitters 7 and the laser receivers 8.

[0033] In the first implementation, the arrangement of the laser emitters 7 and the laser receivers 8 is as shown in FIG. 1. Figure 4 Figure 4 Taking the circular mounting bracket 9 as an example, the number of the laser emitters 7 and the laser receivers 8 is N, which are respectively a first laser emitter, a second laser emitter, …, an Nth laser emitter, a first laser receiver, a second laser receiver, …, an Nth laser receiver arranged in sequence on a part of the circumference of the mounting bracket 9. The circular arc between the first laser emitter and the Nth laser emitter and the center of the mounting bracket 9 form a sector region, and the lasers emitted by the N laser emitters intersect with each other during transmission to form a large number of intersection points, which should cover the sector region as evenly as possible or cover the region close to the center of the mounting bracket 9 in the sector region as evenly as possible. The advantage of this implementation is that only a small number of laser emitters 7 and laser receivers 8 are needed to realize measurement, the system structure is simple, the cost is low, and it is convenient to carry out experiments. Moreover, the circular mounting bracket 9 is superior to the rectangular mounting bracket 9 in adaptability to various temperature fields.

[0034] In the second implementation, the arrangement of the laser emitters 7 and the laser receivers 8 is as shown in FIG. 2. Figure 5 Figure 5 Taking the rectangular mounting bracket 9 as an example, the laser emitters 7 are divided into two groups on average. The respective laser emitters 7 in the group are arranged at equal intervals, and the laser emission directions are parallel to each other. The laser emission directions of the two groups of laser emitters 7 are perpendicular to each other, and the lasers emitted by the two groups of laser emitters 7 intersect with each other to form a grid. The two groups of laser emitters 7 and the two groups of laser receivers 8 can be arranged on the four sides of the mounting bracket 9. The advantage of this implementation is that the arrangement of the laser emitters 7 and the laser receivers 8 is relatively simple, the arrangement process is easy to operate, and it is convenient to carry out experiments.

[0035] In the third implementation, the arrangement of the laser emitters 7 and the laser receivers 8 is as shown in FIG. 3. Figure 6 Figure 6 ​​​Taking the rectangular mounting bracket 9 as an example, the laser emitters 7 are arranged at equal intervals and the laser emission directions are parallel to each other. The laser emitters 7 and the laser receivers 8 can be arranged on two opposite edges of the mounting bracket 9 respectively. During the measurement, the propagation paths of the laser emitted by each laser emitter 7 at the current position and the propagation paths of the laser emitted by each laser emitter 7 at the previous position form a series of intersection points. The advantage of the present implementation lies in that the arrangement of the laser emitters 7 and the laser receivers 8 is relatively simple and easy to operate, which facilitates the experiment.

[0036] The data processing module 12 receives various parameters set by the user, which can include, for example, the waveform, period, amplitude, duty cycle, etc. of the electrical signals output by the first laser controller 1 and the second laser controller 2, and the electrical signal waveform can be, for example, a triangular wave. These parameters are applied to the first laser controller 1 and the second laser controller 2 through the data acquisition card 11, and the first laser controller 1 and the second laser controller 2 output corresponding electrical signals according to the set parameters. The electrical signals output by the first laser controller 1 and the second laser controller 2 serve as the power supply for the first laser 3 and the second laser 4, respectively, and the first laser 3 and the second laser 4 output laser beams of different frequencies. After the two laser beams are combined by the beam combiner 5, they are split into multiple laser beams by the beam splitter 6. Each laser beam enters a laser emitter 7 and is emitted by the laser emitter 7, which can be implemented by a fiber collimator. The central region of the mounting bracket 9 is a flame field, and the laser emitted by the laser emitter 7 is absorbed by the combustion products during its passage through the flame field. The absorbed optical signal is received by the laser receiver 8, which converts the received optical signal into an electrical signal. The electrical signal is collected by the data acquisition card 11, which inputs the collected electrical signal to the data processing module 12 for calculation to obtain the position coordinates of each laser intersection point and the temperature at each position coordinate.

[0037] The method for measuring the three-dimensional combustion temperature field of a gas using the above system is as follows:

[0038] 1. Adjust the height of the support structure 10 according to a preset first step size.

[0039] 2. After each adjustment of the height, control the mounting bracket 9 to rotate one period according to a preset second step size. The second step size and the angle covered by one period are determined according to the arrangement of the laser emitters 7. For example, in the arrangement shown in FIG. 8, one period is 360 degrees; for example, in the arrangement shown in FIG. 9, one period is 180 degrees; and for example, in the arrangement shown in FIG. 10, one period is 90 degrees. Figure 4 Figure 5 Figure 6 ​​The arrangement shown is an example, one cycle is 360 degrees. The smaller the second step, the more accurate the measurement result, the larger the second step, the faster the measurement speed, the actual situation can be weighed between accuracy and speed, and the appropriate step value is selected.

[0040] Each time the mounting bracket 9 rotates one cycle, all the laser transmission paths in the cycle will form a large number of intersection points. The coordinates and temperatures of each intersection point are calculated according to the data collected by the data acquisition card 11, and the high-temperature points are marked. These high-temperature points include real high-temperature points and "ghost points". The "ghost points" generated by the mounting bracket 9 during rotation usually appear only once, while the real high-temperature points usually appear at least twice. Therefore, the high-temperature points that appear only once are removed as "ghost points", and the remaining high-temperature points are retained as real high-temperature points. For example, when the mounting bracket 9 rotates to a certain angle, A, B, C, and D four high-temperature points appear, and when the mounting bracket 9 rotates to the next angle, A', B', C', and D' four high-temperature points appear. The coordinates of the eight high-temperature points are calculated, the distance between A and A' is , the distance between B and B' is , the distance between C and C' is , the distance between D and D' is , and and are both less than the allowable error range δ, while and both exceed δ, indicating that A and A' are actually the same point, C and C' are also the same point, while B and B' are two different points, and D and D' are also two different points. Then A and C will be retained as real high-temperature points. If the mounting bracket 9 does not appear again during the subsequent rotation in the current cycle, B, B', D, and D' are all "ghost points".

[0041] 3. After the height adjustment of the support structure 10 is completed, the three-dimensional combustion temperature field of the gas is restored according to the temperature and coordinates of each point at each height. The height adjustment range of the support structure 10 should cover the entire three-dimensional combustion temperature field of the gas, and the height adjustment step of the support structure 10 can be set according to the specific situation of the actual three-dimensional combustion temperature field of the gas.

[0042] According to the Lambert-Beer ( ) law, when a laser beam with frequency and intensity passes through a gas cell with an optical path of , the gas molecules to be measured will selectively absorb light of a certain frequency band, resulting in a decrease in light intensity to , and the transmitted light intensity can be expressed as:

[0043]

[0044] wherein, is the light absorption coefficient, which can be described by equation (2):

[0045]

[0046] The above equation is the classic Lambert-Beer absorption theorem, which is the theoretical basis of the TDLAS testing method. Among them, is the absorption line intensity, and the absorption line intensity at the reference temperature is obtained by referring to the HITRAN database value, and then the line intensity at temperature is calculated by equation (3) .

[0047]

[0048] wherein, the subscript represents the th spectrum line; is the Planck constant; is the speed of light; is the Boltzmann constant; is the transition frequency; represents the transition frequency corresponding to the th spectrum line; is the low transition state energy; is the total molecular internal partition function, which is usually obtained by polynomial fitting method.

[0049] The direct absorption method is one of the most commonly used gas detection methods, which has the advantages of simple operation and easy implementation. Its measurement principle is based on the characteristics of semiconductor lasers. A signal generator and a laser driver are used to inject a sawtooth wave or sinusoidal current signal into the laser to control the output wavelength of the laser, so that it can scan the waveband covering the gas absorption peak to be detected. After the laser is absorbed by the gas in the to-be-detected field, the attenuated light intensity signal is received by the detector, and the light signal is converted into an electric signal, which is input into the data acquisition card and finally transmitted to the computer for data processing. According to the Lambert-Beer law, the temperature and concentration of the to-be-detected gas are inversely calculated by processing the light intensity before and after the gas absorption.

[0050] As can be seen from equation (3), the line intensity of the spectrum line is a single-parameter function of temperature , and the temperature and the line intensity ​The relationship between the two can realize the measurement of the gas temperature, the basic principle is that the amplitude changes of the line strength of different spectral lines are different due to the change of temperature, two relatively independent spectral lines are selected as the test objects, the relative values of the line strength at different temperatures are calculated, and the average temperature on the measured light path is calculated by using the relative values of the line strength of the two absorption spectral lines. The relative values of the line strength of the two absorption spectral lines can be expressed as:

[0051]

[0052] Wherein, the subscript 1 represents the first spectral line, and the subscript 2 represents the second spectral line.

[0053] The integral absorbance A can be obtained by integrating both sides of equation (1) simultaneously. That is, the expression of the absorption spectral line coverage area:

[0054]

[0055] Wherein, is the total pressure of the gas, is the molar fraction of the absorption gas, is the line shape function of the absorption spectral line.

[0056] It is not difficult to see that when the direct absorption method is used to realize temperature measurement, the concentration value of the gas and the environmental pressure will not affect the accuracy of the test results. The temperature can be obtained by the following formula:

[0057]

[0058] The temperature calculated by formula (6) is the average temperature of the propagation path of a laser beam. The two laser beams intersect, and the average temperature of the propagation path of each laser beam is calculated respectively, and the average of the two average temperatures is taken as the temperature of the intersection point of the two laser beams. According to the propagation direction of the two laser beams and the position of the laser emitter 7, the intersection point coordinates of the two laser beams can be calculated.

[0059] Based on the above principle, taking the arrangement shown in Figure 4 The gas three-dimensional combustion temperature field measurement method of the embodiment of the application specifically includes the following steps:

[0060] Step one, adjust the support structure 10 to the lowest point of the to-be-measured area, set the scanning current signal output by the data acquisition card 11 through the upper computer embedded with the data processing module 12, control the temperature and current of the two lasers by two laser controllers respectively, so that the two lasers can work in time to produce laser, and then enter step two.

[0061] Step two, the host computer calculates according to the data collected by the data acquisition card 11, obtains the coordinates and temperature values of all intersection points in the laser propagation area, and marks the high temperature points according to the temperature values, and then enters step three.

[0062] Step three, control the installation support 9 to rotate in a certain direction (clockwise or counterclockwise) by one step (step , for example, can be ), and then return to step two until the installation support 9 rotates cumulatively to complete the measurement of this cycle and enter step four.

[0063] Step four, compare the calculation results of each time in this cycle, if a certain high temperature point exists in the calculation results of continuous times, it is considered that the high temperature point is a real high temperature point, and the high temperature point is retained; if a certain high temperature point exists only in a calculation result, it is considered that the high temperature point is a "ghost point", and the high temperature point is deleted, and then enter step five.

[0064] The comparison times can be set in advance, the closer the laser emitters 7 are arranged, the smaller the value of the second step is, and the larger the comparison times should be. For example, there are 8 laser emitters 7, the angle between adjacent two laser emitters 7 is Figure 4 , the second step is , and the comparison times can be set to 2, so the real high temperature point should exist in at least two continuous calculation results. It should be noted that in one cycle, the installation support 9 rotates times, and the installation support 9 will return to the initial position when the th rotation is completed, so the first calculation result in a cycle and the th calculation result in the cycle should be considered as adjacent two calculation results. For example, the step is , so the first calculation result in a cycle and the 360th calculation result are adjacent two calculation results. Step five, use spline interpolation to smooth the calculation data of this cycle after filtering out the "ghost points" to obtain high-resolution two-dimensional distribution data of the temperature field, and then enter step six.

[0065] Step six, adjust the height of the support structure 10 so that the height increases by one step, and then return to step two until the height adjustment range of the support structure 10 completely covers the to-be-measured area, and then enter step seven.

[0066] Step seven, the host computer obtains the two-dimensional distribution data of the temperature field of the to-be-measured area, and then the measurement is completed.

[0067] Step seven, according to the temperature field two-dimensional distribution data of each height of the support structure 10, the temperature distribution of the three-dimensional combustion temperature field of the gas to be measured is restored. As shown in Figure 7 the temperature distribution of the three-dimensional combustion temperature field of the gas to be measured is restored according to the temperature field two-dimensional distribution data of the three heights of the support structure 10.

[0068] The data processing module 12 of the embodiment can be realized in combination with hardware or software, or a combination thereof. Therefore, the method and device of the application, or certain aspects or parts of the method and device of the application can take the form of program code (i.e. instructions) embedded in a tangible medium, such as a removable hard disk, a U disk, a floppy disk, a CD-ROM or any other machine-readable storage medium, wherein when the program is loaded into a machine, such as a computer, and executed by the machine, the machine becomes the device for practicing the application.

Claims

1. A method for measuring a three-dimensional combustion temperature field of a gas, based on a rotating light path-based three-dimensional combustion temperature field measurement system, the rotating light path-based three-dimensional combustion temperature field measurement system comprising: The first laser controller, the second laser controller, the first laser, the second laser, the beam combiner, the beam splitter, the plurality of laser emitters, the plurality of laser receivers, the mounting bracket capable of rotating around its central axis by a preset step, the support structure capable of extending in the vertical direction, the data acquisition card, and the data processing module; The mounting bracket is fixed on the top of the support structure, and the to-be-measured region is located in the region surrounded by the mounting bracket; The plurality of laser emitters are arranged on the mounting bracket, and the laser emitted by the plurality of laser emitters is located in the plane where the mounting bracket is located; The plurality of laser receivers are arranged on the mounting bracket, and the plurality of laser emitters and the plurality of laser receivers correspond to each other in one-to-one manner; The data processing module sends control signals to the first laser controller and the second laser controller and receives data collected by the plurality of laser receivers through the data acquisition card; The first laser controller and the second laser controller control the first laser and the second laser, respectively, according to the received control signals; The laser of different frequencies output by the first laser and the second laser enters the beam combiner and the beam splitter in sequence and is divided into a plurality of beams of laser, and the plurality of beams of laser are emitted by the plurality of laser emitters, respectively. The method comprises: Adjusting the height of the support structure according to a preset first step; After adjusting the height once, controlling the mounting bracket to rotate one period according to a preset second step, calculating the temperature and coordinates of each point in the to-be-measured region according to the data collected by the data acquisition card, and deleting the high-temperature point that appears only once during the rotation of the mounting bracket; After the height adjustment of the support structure is completed, restoring the three-dimensional combustion temperature field of the gas according to the temperature and coordinates of each point at each height.

2. The method of claim 1, wherein, The first laser controller and the second laser controller send triangular wave electrical signals to the first laser and the second laser under the control of the data processing module.

3. The method of claim 1 or 2, wherein, The plurality of laser emitters are arranged at equal intervals, and the laser emission directions of the plurality of laser emitters are parallel to each other.

4. The method of claim 1 or 2, wherein, The intersection points formed by the laser emitted by the plurality of laser emitters are uniformly distributed in the to-be-measured region.

5. The method of claim 1 or 2, wherein, The intersection points formed by the laser emitted by the plurality of laser emitters are uniformly distributed in part of the to-be-measured region.

6. The method of claim 1, wherein, The support structure comprises three telescopic rods, and the three telescopic rods are driven by a motor to realize telescoping.

7. The method of claim 1, wherein, The support structure comprises three L-shaped support rods and one telescopic rod, the mounting bracket is installed at one end of the three L-shaped support rods, the other end of the three L-shaped support rods is fixed at one end of the telescopic rod, and the telescopic rod is driven by a motor to realize telescoping.

8. The method of claim 1, wherein, The laser emitter adopts a fiber collimator.

9. The method of claim 1, wherein, The second step is less than or equal to the angular interval of adjacent two laser emitters.

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