High spatio-temporal resolution optical experimental system and experimental method for measuring non-equilibrium flow field components and temperature

Abstract

The present invention discloses a high spatiotemporal resolution optical test system and test method for non-equilibrium flow field component and temperature measurement, which relates to the field of non-equilibrium flow field test and measurement. The system includes: a test environment module for generating a detached shock wave generated at the leading edge of an aircraft during flight; a first absorption spectroscopy measurement module for measuring the generation and dissipation signals of NO in the detached shock wave layer; a second absorption spectroscopy measurement module for measuring the generation and dissipation signals of O and N in the detached shock wave layer; a signal acquisition and data analysis module for recording the generation and dissipation signals of O, N, and NO to obtain original signals, and inversely calculating the flow field temperature at the measured position according to the original signals. The present invention can realize multi-position and high-time-resolution non-contact test measurement of non-equilibrium characteristics in the detached shock wave layer at the leading edge of a hypersonic aircraft during a ground wind tunnel test.

Description

Technical Field

[0001] The present invention relates to the field of non - equilibrium flow field test and measurement. Specifically, it relates to a high - spatio - temporal resolution optical test system and test method for non - equilibrium flow field component and temperature measurement. Background Art

[0002] The non - equilibrium flow state formed by the detached shock layer at the leading edge of an aircraft often appears in the near - wall region of hypersonic aircraft moving at high speeds in the atmosphere such as a re - entry capsule. The speed of the aircraft can reach up to 10,000 kilometers per hour. The high total temperature brought by high - speed movement causes oxygen and nitrogen to dissociate and ionize successively when the air flow stagnates. Currently, there is no optical measurement of the above - mentioned non - equilibrium flow field during flight tests. During ground tests, due to reasons such as the difficulty in simulating the flight environment and the inability of measurement techniques to effectively match the test environment, there are few reported experimental methods for quantitatively, synchronously, highly time - resolved, and non - contact measurement of physical quantities in the detached shock layer of the non - equilibrium flow field. Summary of the Invention

[0003] The object of the present invention is to achieve multi - position and high - time - resolution non - contact test measurement of non - equilibrium characteristics in the detached shock layer at the leading edge of a hypersonic aircraft during ground wind tunnel tests.

[0004] To achieve the above - mentioned object of the invention, the present invention provides a high - spatio - temporal resolution optical test system for non - equilibrium flow field component and temperature measurement. The system includes:

[0005] A test environment module for generating a detached shock generated at the leading edge of an aircraft in a flight state;

[0006] A first absorption spectrum measurement module for measuring the generation and dissipation signals of NO in the detached shock layer;

[0007] A second absorption spectrum measurement module for measuring the generation and dissipation signals of O and N in the detached shock layer;

[0008] A signal acquisition and data analysis module for recording the generation and dissipation signals of O, N, and NO to obtain the original signals, and inversely calculating the flow field temperature at the measured position according to the original signals.

[0009] Among them, in the present invention, the flight environment is simulated by means of arc heating, ultra-high pressure drive, and evacuation to reduce the back pressure. The gas is heated by an arc to initially obtain a relatively high temperature; the gas with ultra-high pressure upstream is used to drive the test gas downstream by extrusion, so that the test gas has a high total pressure; a vacuum pump is used downstream of the test section to evacuate the test section to a vacuum state, so that a high pressure ratio is formed between the upstream and downstream. According to the characteristics of the three substances O, N, and NO that may exist in the non-equilibrium flow field and the possible high temperature, high pressure, small area, and restricted space of the measured flow field, the lasers required for the absorption spectra of each substance, the compact space layout design, and the sapphire wedge optical glass visualization window are preferably used to match the test environment to achieve a high-quality and efficient test effect.

[0010] Among them, based on the absorption characteristics of different substances for lasers with specific wavelengths, in the present invention, the applicable absorption spectral lines are respectively selected according to the absorption characteristics of O, N, and NO for lasers with different wavelengths, the laser wavelength is selected according to the spectral line, and then through optical path design, environment construction, multi-system matching, and based on the single-line temperature measurement method and double-line temperature measurement method of absorption spectroscopy (such as the literature Zhang Guangle. Research on the Measurement Method of One-dimensional Temperature Inhomogeneity Based on Multi-absorption Line TDLAS [D]. Hefei: University of Chinese Academy of Sciences, 2016.), etc., during the ground wind tunnel test process, a multi-position and high-time-resolution non-contact test measurement method for the non-equilibrium characteristics in the detached shock layer at the leading edge of the hypersonic vehicle is obtained.

[0011] Among them, in some embodiments, the test environment module includes:

[0012] A model tester for simulating the physical entity of the aircraft;

[0013] A tester support frame for fixedly supporting the model tester at a position corresponding to the central streamline at the outlet of the incoming flow nozzle in the wind tunnel measurement section;

[0014] A wind tunnel measurement section for providing a test space for the model tester and signal measurement;

[0015] An incoming flow nozzle for generating the flow field conditions for simulating the flight environment;

[0016] The first wedge-shaped sapphire window and the second wedge-shaped sapphire window are both used to support optical tests and enable light to pass through the measurement area.

[0017] Among them, in some embodiments, the first absorption spectrum measurement module includes:

[0018] A first semiconductor laser in the 1900 nm band for generating laser light that scans at a fixed frequency within a certain range;

[0019] A first laser controller for controlling the output wavelength and frequency of the first semiconductor laser in the 1900 nm band;

[0020] A 1900nm-band photodetector for receiving the signal after the laser emitted by the first 1900nm-band semiconductor laser passes through the flow field;

[0021] The first optoelectronic signal acquisition line for transmitting the signal collected by the 1900nm-band photodetector to the industrial control computer;

[0022] The first signal synchronization line for transmitting the synchronization trigger signal.

[0023] Wherein, in some embodiments, the first 1900nm-band semiconductor laser generates laser light that passes through the first wedge-shaped sapphire window into the test area and then passes through the second wedge-shaped sapphire window and enters the 1900nm-band photodetector. The 1900nm-band photodetector is connected to the industrial control computer through the first optoelectronic signal acquisition line, and the industrial control computer is connected to the first laser controller through the first signal synchronization line.

[0024] Wherein, in some embodiments, the second absorption spectrum measurement module includes:

[0025] The first 777nm-band semiconductor laser for generating laser light that scans at a fixed frequency within a certain range;

[0026] The first 824nm-band semiconductor laser for generating laser light that scans at a fixed frequency within a certain range;

[0027] The first 926nm-band semiconductor laser for generating laser light that scans at a fixed frequency within a certain range;

[0028] The second laser controller for controlling the output wavelengths and frequencies of the first 777nm-band semiconductor laser, the first 824nm-band semiconductor laser, and the first 926nm-band semiconductor laser;

[0029] A 777nm - 926nm-band photodetector for receiving the signals after the laser light emitted by the first 777nm-band semiconductor laser, the first 824nm-band semiconductor laser, and the first 926nm-band semiconductor laser passes through the flow field;

[0030] The second to fifth optoelectronic signal acquisition lines are all used to transmit the signals collected by the 777nm - 926nm-band photodetector to the industrial control computer;

[0031] The second signal synchronization line for transmitting the synchronization trigger signal;

[0032] The first wavelength division multiplexer for combining the laser lights generated by the first 777nm-band semiconductor laser, the first 824nm-band semiconductor laser, and the first 926nm-band semiconductor laser to obtain combined laser light;

[0033] A second wavelength division multiplexer for splitting the combined laser beam into four laser beams;

[0034] The first to fourth laser collimators are respectively used for collimating the four laser beams split by the second wavelength division multiplexer;

[0035] A reflection prism mounting table for fixing the first to third prisms;

[0036] The first to third prisms are used to change the transmission directions of the laser beams collimated by the first to fourth laser collimators.

[0037] Among them, in some embodiments, the second laser controller controls the first semiconductor laser at 777 nm wavelength band, the first semiconductor laser at 824 nm wavelength band, and the first semiconductor laser at 926 nm wavelength band to respectively generate laser beams at 777 nm wavelength band, 824 nm wavelength band, and 926 nm wavelength band. The laser beams at 777 nm wavelength band, 824 nm wavelength band, and 926 nm wavelength band are combined into a combined laser beam through the first wavelength division multiplexer. The combined laser beam is split into four laser beams through the second wavelength division multiplexer. The four laser beams are respectively collimated by the first to fourth laser collimators. The laser beam collimated by the first laser collimator is reflected by the first prism and then enters the test area. The laser beams collimated by the second and third laser collimators are reflected by the second prism and then enter the test area. The laser beam collimated by the fourth laser collimator is reflected by the third prism and then enters the test area.

[0038] Among them, in some embodiments, the first wedge-shaped sapphire window and the second wedge-shaped sapphire window are symmetrically installed on both sides of the incoming flow nozzle with respect to the central streamline of the incoming flow nozzle.

[0039] Among them, in some embodiments, the signal acquisition and data analysis module includes an industrial control computer and a signal monitor. The industrial control computer is used to control the first and second laser controllers, and to collect and store the information of the 1900 nm wavelength band photodetector and the 777 nm - 926 nm wavelength band photodetector, and to process the test data; the signal monitor is used to monitor and display the control program.

[0040] Among them, in some embodiments, 4 photoelectric converters are integrated in the 777 nm - 926 nm wavelength band photodetector, and the detection windows of the 4 photoelectric converters are evenly spaced and parallelly distributed.

[0041] The present invention also provides a test method for a high spatio-temporal resolution optical test system based on the measurement of non-equilibrium flow field components and temperature, and the method includes:

[0042] Step 1: Set up the test system;

[0043] Step 2: Connect the various components in the test system;

[0044] Step 3: Turn on the equipment in the test system;

[0045] Step 4: Adjust the first absorption spectrum measurement module to meet the signal detection requirements;

[0046] Step 5: Adjust the position of the laser spot on the model tester in the test environment module and determine the distance between the spot and the model tester;

[0047] Step 6: Adjust the second absorption spectrum measurement module to meet the signal detection requirements;

[0048] Step 7: Return to Step 5 until the optical path adjustment is completed;

[0049] Step 8: Close the test section hatch and start the test;

[0050] Step 9: Adjust each module in the system to the standby state;

[0051] Step 10: Turn on the test environment module and send a test start signal to the first absorption spectrum measurement module, the second absorption spectrum measurement module, and the signal acquisition and data analysis module;

[0052] Step 11: After receiving the test start signal, the first absorption spectrum measurement module, the second absorption spectrum measurement module, and the signal acquisition and data analysis module start to emit lasers and collect optoelectronic signals;

[0053] Step 12: At the preset test end moment, the test environment module stops working, and then the first absorption spectrum measurement module, the second absorption spectrum measurement module, and the signal acquisition and data analysis module stop working;

[0054] Step 13: The test ends, and the original signal is checked;

[0055] Step 14: Result processing and analysis.

[0056] One or more technical solutions provided by the present invention have at least the following technical effects or advantages:

[0057] The present invention can realize multi-position and high-time-resolution non-contact test measurements of the non-equilibrium characteristics in the detached shock layer at the leading edge of a hypersonic vehicle during a ground wind tunnel test. Description of the Drawings

[0058] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, form a part of the present invention, and do not limit the embodiments of the present invention;

[0059] Figure 1 It is a schematic diagram of the composition of a high spatio-temporal resolution optical test system for non-equilibrium flow field component and temperature measurement;

[0060] Figure 2 It is a schematic diagram of the measuring points at the test site;

[0061] Figure 3 It is a schematic diagram of the timing relationship of the appearance and disappearance of NO, O, and N signals;

[0062] Figure 4 It is a schematic diagram of the test results. Specific implementation manners

[0063] In order to more clearly understand the above-mentioned objects, features, and advantages of the present invention, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific implementation manners. It should be noted that, without conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

[0064] In the following description, many specific details are set forth in order to fully understand the present invention. However, the present invention can also be implemented in other ways different from those described within the scope here. Therefore, the protection scope of the present invention is not limited by the specific embodiments disclosed below.

[0065] Embodiment 1;

[0066] Please refer to Figure 1 , Figure 1 It is a schematic diagram of the composition of a high spatio-temporal resolution optical test system for measuring non-equilibrium flow field components and temperature. The whole system includes multiple components and necessary accessories such as optical fiber connectors. The names and main functions of each component are as follows: Model tester 1, used to simulate the aircraft entity; Tester support frame 2, used to support the model tester at the central streamline position of the outlet of the incoming flow nozzle; Wind tunnel measurement section 3, used to provide a test space for the model and measurement technology; Incoming flow nozzle 4, used to generate flow field conditions simulating the real flight environment; First wedge-shaped sapphire window 5, used to support optical tests so that light can pass through the measurement area; Second wedge-shaped sapphire window 6, with the same function as 5;

[0067] The first 1900 nm band semiconductor laser 7 is used to generate a laser that can be scanned at a fixed frequency within a certain range. The range and frequency are controlled by the first laser controller 8 according to the specific test object. The laser of this band can be absorbed by NO, thereby causing a change in the signal collected by the 1900 nm band photodetector 9. The flow field parameters can be calculated by inversion through the specific change amount; the first laser controller 8 controls the output wavelength and frequency of the first 1900 nm band semiconductor laser 7; the 1900 nm band photodetector 9 receives the signal after the laser emitted by the first 1900 nm band semiconductor laser 7 passes through the flow field; the first photoelectric signal acquisition line 10 transmits the signal collected by the 1900 nm band photodetector to the industrial control computer 31; the first signal synchronization line 11 is used to transmit the synchronization trigger signal;

[0068] The first 777 nm band semiconductor laser 12 is used to generate a laser that can be scanned at a fixed frequency within a certain range. The range and frequency are controlled by the second laser controller 15 according to the specific test object. The laser of this band can be absorbed by O, thereby causing a change in the signal collected by the 777 nm - 926 nm band photodetector 16. The flow field parameters can be calculated by inversion through the specific change amount; the first 824 nm band semiconductor laser 13 is used to generate a laser that can be scanned at a fixed frequency within a certain range. The range and frequency are controlled by the second laser controller 15 according to the specific test object. The laser of this band can be absorbed by N, thereby causing a change in the signal collected by the 777 nm - 926 nm band photodetector 16. The flow field parameters can be calculated by inversion through the specific change amount; the first 926 nm band semiconductor laser 14 is used to generate a laser that can be scanned at a fixed frequency within a certain range. The range and frequency are controlled by the second laser controller 15 according to the specific test object. The laser of this band can be absorbed by O, thereby causing a change in the signal collected by the 777 nm - 926 nm band photodetector 16. The flow field parameters can be calculated by inversion through the specific change amount;

[0069] The second laser controller 15 is used to control the output wavelength and frequency of 12 - 14; the 777nm - 926nm band photodetector 16 is used to receive the signal after the laser emitted by 12 - 14 passes through the flow field; the second photoelectric signal acquisition line 17 is used to transmit the signal collected by the 777nm - 926nm band photodetector 16 to the industrial control computer 31; the third photoelectric signal acquisition line 18 has the same function as 17; the fourth photoelectric signal acquisition line 19 has the same function as 17; the fifth photoelectric signal acquisition line 20 has the same function as 17; the second signal synchronization line 21 is used to transmit the synchronous trigger signal; the second wavelength division multiplexer 22 (1 input and 4 outputs) is used to divide 1 beam of laser into 4 beams; the first laser collimator 23 is used to improve the collimation of the laser at the end of the second wavelength division multiplexer 22; the second laser collimator 24 has the same function as 23; the third laser collimator 25 has the same function as 23; the fourth laser collimator 26 has the same function as 23; the reflecting prism mounting table 27 is used to fix the first to third prisms; the first prism 28 is used to change the laser transmission direction; the second prism 29 has the same function as 28; the third prism 30 has the same function; the industrial control computer 31 is used to control 8 and 15, collect and store the information of 9 and 16, and process the test data; the signal monitor 32 controls the visualization medium of the program.

[0070] The spatial relationship of each component is as Figure 1 shown. Components 1 - 6 form the test environment module, which is used to generate the detached shock wave generated at the leading edge of the aircraft during the flight of the simulated hypersonic aircraft; components 7 - 11 form the NO absorption spectrum measurement module (i.e., the first absorption spectrum measurement module), which is used to measure the generation and elimination signals of NO in the shock layer; components 12 - 30 form the 4 - channel absorption spectrum measurement module for two components of O and N (i.e., the second absorption spectrum measurement module), which is used to measure the generation and elimination signals of O and N in the shock layer; components 31 and 32 form the signal acquisition and data analysis module, which is used to record the original signals of the three components of O, N, and NO and invert the flow field temperature at the measured position according to the original signals.

[0071] Figure 1 Among them, 777, 824, 926, and 1900 represent semiconductor lasers in the corresponding bands respectively.

[0072] The details that need to be specifically explained for each module are as follows:

[0073] Test environment module: Components 5 and 6 are two symmetrically installed wedge - shaped sapphire glass windows, and these two pieces of glass are used to Figure 1The five detection lights shown effectively pass through the flow field. The sapphire material supports the high transmittance of the four laser wavelengths of 777 nm, 824 nm, 926 nm, and 1900 nm required in this system through the glass medium. The wedge shape is used to solve the interference clutter information formed at the detection end due to plane reflection of the laser, making the detection signal cleaner so that weak signals can be efficiently extracted.

[0074] NO measurement module: Component 7 can generate spatially coherent light in the 1900 nm band with relatively high collimation, so no additional laser collimator is required.

[0075] O, N four-channel measurement module: The laser wavelengths of the three bands of 777 nm, 824 nm, and 926 nm have relatively small differences, enabling efficient transmission and splitting of light in the same medium. O has absorption in both the 777 nm and 926 nm bands, and N has absorption at 824 nm. Therefore, in the present invention, the lasers of these three bands are designed in a manner of first combining and then splitting. The combining process uses a first wavelength division multiplexer with 3 inputs and 1 output, and the splitting process uses a second wavelength division multiplexer with 1 input and 4 outputs. Combining serves two purposes. The first purpose is to measure the signals of O and N simultaneously at the same position. The second purpose is to simultaneously use single-wavelength calculations for O and N results and double-wavelength calculations for O results during component and temperature inversion, and complement each other between different calculation methods to finally output a result with higher credibility. The four-channel multi-wavelength laser output by the second wavelength division multiplexer has poor collimation and is connected to the collimator through flexible optical fibers. The laser output from the output end of the collimator has the same relatively high collimation as component 7. Different from component 7, the lasers output by components 23 - 26 are multi-wavelength lasers. The laser output from the collimator is reflected into the measured flow field through three reflecting prisms fixed on component 27. By adjusting the adjustment frame on the collimator, the spacing and direction of the four-channel lasers can be finely adjusted. Component 16 is a multi-wavelength photodetector integrating four photoelectric converters, and the four detection windows are equally spaced and parallelly distributed.

[0076] Signal acquisition and data analysis module: This module realizes two functions. The first function is to synchronously acquire five-channel photoelectric signals, and the second function is to post-process the signals to obtain the temperature information of the non-equilibrium flow field.

[0077] The two laser controllers, component 8 and component 15, can enable the lasers to scan within their respective wavelength bands at a fixed frequency (for example, component 8 can control component 7 to scan within the range of 1989 nm - 1901 nm at a frequency of 10 kHz, so that multiple absorption peaks of NO within this wavelength band can be recorded at a high frequency). The acquisition board card in component 31 can achieve data acquisition at MHz or even higher frequencies, and during the experiment, through the signal synchronization line and basic settings, it realizes synchronous acquisition at the same frequency as component 8 and component 15.

[0078] Embodiment 2;

[0079] Based on Embodiment 1, the present invention provides a test method corresponding to the above test system, which specifically includes:

[0080] Step1: Install the model tester in the wind tunnel measurement section, adjust the position so that it is near the central axis of the incoming flow nozzle, and the leading edge of the model tester is in the observable area of the optical glass;

[0081] Step2: Place an optical platform on each side of the wind tunnel measurement section for installing measurement and monitoring equipment;

[0082] Step3: Fix the components on both sides of the wind tunnel measurement section shown in Figure 1 by means of screws, nuts, etc., and make the laser emission and reception positions at the same height;

[0083] Step4: Connect each component according to the relationship shown in Figure 1 ;

[0084] Step5: Turn on the laser, laser controller, photodetector, industrial computer and signal monitor;

[0085] Step6: Adjust the relative positions of component 7 and component 9 so that component 9 can detect the signal of component 7;

[0086] Step7: Use an infrared light-sensitive plate to check the position of the laser spot near the model tester, ensure that the spot position is in the ideal measured area, that is, near the leading edge of the model tester but not blocked by the model, and determine the distance between the spot and the model;

[0087] Step8: Adjust the relative positions between component 23-26 and component 16 so that component 16 can detect the signal of component 23-26;

[0088] Step9: Repeat step7;

[0089] Step10: After the optical path debugging is completed, close the test section hatch and prepare to start the test;

[0090] Step11: Adjust each module to the standby state;

[0091] Step12: Turn on the test environment module and send a test start signal to the other 3 modules;

[0092] Step13: After receiving the test start signal, the 2 measurement modules and the acquisition module start to emit laser and collect optoelectronic signals;

[0093] Step 14: At the preset test end moment, the test environment module stops working first, and then the other three modules stop working simultaneously;

[0094] Step 15: The test ends, and the original signal is checked;

[0095] Step 16: Result processing and analysis.

[0096] Please refer to Figure 2 , Figure 2 the schematic diagram of measuring points at the test site. The present invention realizes the acquisition of multi-wavelength absorption signals of O and N for the measuring points shown, and the distance between each measuring point is about 7 mm; the measuring points of NO are located between measuring point ① and measuring point ④, realizing the acquisition of single-channel and single-wavelength absorption signals of NO; through the acquisition of multi-component and high-time-resolution absorption spectral information with multi-wavelength and multi-channel, the multi-component non-equilibrium characteristic relationship within the detached shock layer during the ground test of the hypersonic vehicle is obtained Figure 2 as shown in Figure 3 ; through data processing and analysis, the temperature change information at measuring point ①, measuring point ②, and measuring point ③ is obtained, and the time resolution reaches 20 μs. The following conclusions are obtained: 1) The temperature within the detached shock layer can be as high as 10,000 K; 2) Along the flow direction within the detached shock layer, the temperatures at different positions are close but different. As time goes by, the relative high-low relationship of the temperatures at each position has certain changes but the rules are not obvious; 3) After the flow field is established, O2 and N2 in the air flow will first dissociate into O and N. At this time, there is no NO in the flow field. After the high-temperature flow field passes, O and N will recombine to form NO and last for a long time; 4) There is no atomic signal outside the detached shock layer, indicating that the physical quantity gradient between the detached shock layer and the external flow field is very large, and the material composition realizes a high-scale step within the scale of mm magnitude.

[0097] Please refer to Figure 3 , Figure 3 which is Figure 3 the schematic diagram of the timing relationship of the appearance and disappearance of NO, O, and N signals in the test results. Figure 3 It can be seen from Figure 3 that the time period when the wind tunnel is opened is from t0 to t4, the time period when the NO signal is generated is from t3 to t4, and the time periods when the O and N signals are generated are from t1 to t2.

[0098] Figure 4 It is a schematic diagram of test results, Figure 4 The three lines in Figure 2 respectively correspond to the temperatures at the first three measurement positions shown in

[0099] Although the preferred embodiments of the present invention have been described, those skilled in the art can make additional changes and modifications to these embodiments once they know the basic creative concept. Therefore, the appended claims are intended to be construed to include the preferred embodiments as well as all changes and modifications falling within the scope of the present invention.

[0100] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention is also intended to include these modifications and variations.

Claims

1. A high-temporal-spatial resolution optical test system for non-equilibrium flow field component and temperature measurement, characterized by: The system comprises: The test environment module is used to generate the detached shock wave generated by the leading edge of the aircraft in the flight state; The first absorption spectrum measurement module is used to measure the generation and elimination signals of NO in the exfoliated shock layer; The second absorption spectrum measurement module is used to measure the generation and elimination signals of O and N in the exfoliated shock layer; Signal acquisition and data analysis module, used to record the generation and elimination signals of O, N and NO to obtain the original signal, and invert the flow field temperature at the measured position according to the original signal; The second absorption spectrum measurement module includes: The first 777nm band semiconductor laser is used to generate laser light that scans at a fixed frequency within a certain range; The first 824nm band semiconductor laser is used to generate laser light that scans at a fixed frequency within a certain range; The first 926nm band semiconductor laser is used to generate laser light that scans at a fixed frequency within a certain range; A second laser controller, used for controlling the output wavelength and frequency of the first 777nm band semiconductor laser, the first 824nm band semiconductor laser and the first 926nm band semiconductor laser; A 777nm-926nm band photoelectric detector receives signals after the lasers emitted by the first 777nm band semiconductor laser, the first 824nm band semiconductor laser and the first 926nm band semiconductor laser pass through the flow field; The second to fifth photoelectric signal acquisition lines are used to transmit the signals collected by the 777nm-926nm band photoelectric detector to the industrial computer; A second signal synchronization line, used for transmitting a synchronization trigger signal; A first wavelength division multiplexer is used to combine the laser beams generated by the first 777nm band semiconductor laser, the first 824nm band semiconductor laser and the first 926nm band semiconductor laser to obtain a combined laser beam; A second wavelength division multiplexer is used to split the combined laser beam into four laser beams; The first to fourth laser collimators are respectively used to collimate the four laser beams split by the second wavelength division multiplexer; A reflecting prism mounting platform, used for fixing the first to third prisms; The first to third prisms are used to change the transmission direction of the laser after being collimated by the first to fourth laser collimators.

2. The optical test system with high temporal and spatial resolution for measuring non-equilibrium flow field components and temperature according to claim 1, characterized in that: The test environment modules include: Model tester, used to simulate the actual aircraft; A tester support frame is used to fix and support the model tester at a position corresponding to the central streamline of the incoming flow nozzle outlet in the wind tunnel measurement section; The wind tunnel measurement section is used to provide test space for model testers and signal measurements; Incoming flow nozzle, used to generate flow field conditions simulating the flight environment; The first wedge-shaped sapphire window and the second wedge-shaped sapphire window are both used to support optical experiments and allow light to pass through a measurement area.

3. The optical test system with high temporal and spatial resolution for measuring non-equilibrium flow field components and temperature according to claim 1, characterized in that: The first absorption spectrum measurement module includes: The first 1900nm band semiconductor laser is used to generate laser light that scans at a fixed frequency within a certain range; A first laser controller, used for controlling the output wavelength and frequency of the first 1900nm band semiconductor laser; A 1900nm band photoelectric detector, used to receive a signal after the laser emitted by the first 1900nm band semiconductor laser passes through the flow field; The first photoelectric signal acquisition line is used to transmit the signal collected by the 1900nm band photoelectric detector to the industrial computer; The first signal synchronization line is used to transmit a synchronization trigger signal.

4. The optical test system with high temporal and spatial resolution for measuring non-equilibrium flow field components and temperature according to claim 3, characterized in that: The laser generated by the first 1900nm band semiconductor laser passes through the first wedge-shaped sapphire window into the test area and then passes through the second wedge-shaped sapphire window into the 1900nm band photoelectric detector. The 1900nm band photoelectric detector is connected to the industrial computer through the first photoelectric signal acquisition line, and the industrial computer is connected to the first laser controller through the first signal synchronization line.

5. The optical test system with high temporal and spatial resolution for measuring non-equilibrium flow field components and temperature according to claim 1, characterized in that: The second laser controller controls the first 777nm band semiconductor laser, the first 824nm band semiconductor laser and the first 926nm band semiconductor laser to generate lasers of the 777nm band, the 824nm band and the 926nm band respectively. The lasers of the 777nm band, the 824nm band and the 926nm band are combined into a combined laser beam by the first wavelength division multiplexer. The combined laser beam is divided into four laser beams by the second wavelength division multiplexer. The four laser beams are collimated by the first to fourth laser collimators respectively. The laser collimated by the first laser collimator is reflected by the first prism and then emitted into the test area. The laser collimated by the second and third laser collimators is reflected by the second prism and then emitted into the test area. The laser collimated by the fourth laser collimator is reflected by the third prism and then emitted into the test area.

6. The optical test system with high temporal and spatial resolution for measuring non-equilibrium flow field components and temperature according to claim 1, characterized in that: The first wedge-shaped sapphire window and the second wedge-shaped sapphire window are symmetrically mounted on both sides of the incoming flow nozzle with respect to the central streamline of the incoming flow nozzle.

7. The optical test system with high temporal and spatial resolution for measuring non-equilibrium flow field components and temperature according to claim 1, characterized in that: The signal acquisition and data analysis module includes an industrial computer and a signal monitor. The industrial computer is used to control the first and second laser controllers, and is used to collect and store information of the 1900nm band photoelectric detector and the 777nm-926nm band photoelectric detector, and is used to process test data; the signal monitor monitors and displays the control program.

8. The optical test system with high temporal and spatial resolution for measuring non-equilibrium flow field components and temperature according to claim 5, characterized in that: The 777nm-926nm band photoelectric detector integrates four photoelectric converters, and the detection windows of the four photoelectric converters are distributed in parallel with equal intervals.

9. A test method based on a high temporal and spatial resolution optical test system for measuring non-equilibrium flow field components and temperature according to any one of claims 1 to 8, characterized in that: The method comprises: Step 1: Build the test system; Step 2: Connect the components in the test system; Step 3: Turn on the equipment in the test system; Step 4: Adjust the first absorption spectrum measurement module to meet the signal detection requirements; Step 5: Adjust the position of the laser spot on the model tester in the test environment module, and determine the distance between the laser spot and the model tester; Step 6: Adjust the second absorption spectrum measurement module to meet the signal detection requirements; Step 7: Return to step 5 until the optical path is adjusted; Step 8: Close the test section door and start the test; Step 9: Adjust each module in the system to standby mode; Step 10: Turn on the test environment module and send a test start signal to the first absorption spectrum measurement module, the second absorption spectrum measurement module and the signal acquisition and data analysis module; Step 11: The first absorption spectrum measurement module, the second absorption spectrum measurement module and the signal acquisition and data analysis module start emitting lasers and collecting photoelectric signals after receiving the test start signal; Step 12: At the preset end time of the test, the test environment module stops working, and then the first absorption spectrum measurement module, the second absorption spectrum measurement module and the signal acquisition and data analysis module stop working; Step 13: After the test, check the original signal; Step 14: Result processing and analysis.

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