Thermal protection material characteristic detection system based on xenon lamp heating

Abstract

The invention discloses a thermal protection material characteristic detection system based on xenon lamp heating, and belongs to the field of thermal protection material detection. Comprising a high-energy flow solar radiation simulator; the high-energy flow solar radiation simulator comprises a plurality of xenon lamp condensation units for simulating solar radiation, regulation and control of high-energy flow density are realized by adjusting the power of the xenon lamp condensation units, and illumination and temperature measurement is performed on a to-be-measured experimental flat plate arranged at the focus position of the high-energy flow solar radiation simulator; the temperature measurement adopts a mode of combining single-point temperature measurement and full-field temperature distribution measurement, and the obtained temperature measurement data is sent to the upper computer for feedback. Through a xenon lamp high energy flow technology, a composite temperature detection method and an experiment-simulation cooperation mechanism, the problems of insufficient energy flow, single temperature measurement, low optimization efficiency and the like in traditional thermal protection detection are solved.

Description

Technical Field

[0001] The invention belongs to the field of thermal protection material detection, and in particular relates to a thermal protection material characteristic detection system based on xenon lamp heating. Background Art

[0002] With the development of aerospace technology, the flight speed of aircraft is constantly increasing, and the service environment has become more severe. When flying at high speed, the aircraft will be subjected to severe aerodynamic heating, resulting in a sharp increase in surface temperature, far exceeding the temperature resistance limit of the material. Therefore, an effective thermal protection system has become one of the key systems to ensure the safe flight of the aircraft. Thermal protection materials in aerospace systems are an important support means to protect the normal operation of instruments and equipment. They are continuously loaded by heat fluxes such as external plume convection heat transfer and radiation, and have characteristics such as heat transfer coupling, non-uniformity, and transient changes. The external heat flux distribution is an important parameter for the design and evaluation of thermal protection materials. During the flight, aerospace vehicles will be subjected to aerodynamic heating of external high-speed incoming flows and heating of high-temperature combustion gases in the engine combustion chamber, and key hot components need to be thermally protected. The high temperature and high heat flux caused by these extreme conditions will greatly exceed the temperature resistance limit of the material. Therefore, the development of efficient and reliable thermal protection technology has become one of the important bottlenecks restricting the development of aerospace vehicles. The measurement of heat transfer characteristics of thermal protection materials mainly relies on conventional temperature measurement methods such as thermocouples, and it is impossible to directly measure external heat flux. Therefore, it is necessary to use thermal analysis methods to obtain external heat flux data based on temperature measurement data.

[0003] In the field of aerospace, thermal protection detection methods are diverse in terms of heat flow sources, data recording, and simulation methods. Generally speaking, in ground thermal tests in the field of aerospace, quartz lamp heaters are one of the most widely used heating devices at home and abroad. Their main heating components are surface arrays composed of several quartz lamps, which can provide uniform heat flow; xenon lamp equipment can also be used for thermal protection detection. In terms of data recording, thermocouple detection methods are generally used in experiments. In recent years, liquid crystal temperature measurement technology has also become popular. The principle of liquid crystal temperature measurement is based on the thermochromic properties of liquid crystals, that is, liquid crystals present different colors at different temperatures. By accurately measuring the changes in these colors, the temperature value can be determined. In terms of simulation methods, many existing thermal simulation software can be used for thermal protection. For example, SAMCEF Amaryllis can perform ablation analysis on thermal protection materials of high-speed and ultra-high-speed aircraft, including surface ablation, mechanical ablation, chemical ablation, phase change ablation, volume ablation, thermal decomposition, etc., and can simulate thermal mass loss processes such as ablation and sublimation; COMSOL Multiphysics is a multi-physics simulation software, including thermal simulation. It can handle much more complex physical field coupling problems and is suitable for interdisciplinary thermal analysis.

[0004] According to industry surveys, the quartz lamp radiation thermal environment test is currently the most common thermal environment test method in the domestic aviation and aerospace fields. The quartz lamp is small in size, has small thermal inertia, is structurally compact, and is easy to install, making it the most commonly used heat source for thermal tests. However, it is generally applied to the fields of medium and low heat flux experiments in aviation and aerospace and cannot well meet the requirements of high energy flux experiments; most existing thermal protection detection systems use the method of arranging thermocouples, and the detection method is too single and the error is large. One challenge of liquid crystal temperature measurement technology is the precise calibration of color changes, which requires an accurate calibration process to ensure the accuracy of temperature readings. The stability and durability of liquid crystal materials also need to be considered to ensure long-term reliable temperature monitoring. Summary of the Invention

[0005] Technical problems to be solved:

[0006] In order to avoid the deficiencies of the prior art, the present invention provides a thermal protection material property detection system based on xenon lamp heating, which solves the problems of insufficient energy flux, single temperature measurement, and low optimization efficiency in traditional thermal protection detection through xenon lamp high energy flux technology, composite temperature detection method, and experiment-simulation collaboration mechanism. The present invention combines high performance parameters, high-precision detection, low-cost optimization, and wide applicability to provide an efficient and reliable test platform for the research and development of thermal protection materials in aviation and aerospace.

[0007] The technical solution of the present invention is: a thermal protection material property detection system based on xenon lamp heating, including a high energy flux solar radiation simulator; the high energy flux solar radiation simulator includes a plurality of xenon lamp condensing units for simulating solar radiation, and the regulation of high energy flux density is achieved by adjusting the power of the xenon lamp condensing units, and the light irradiation and temperature measurement are carried out on the test experimental flat plate placed at the focal position of the high energy flux solar radiation simulator.

[0008] The temperature measurement adopts a combination of single-point temperature measurement and full-field temperature distribution measurement, and the obtained temperature measurement data is sent to the host computer for feedback.

[0009] A further technical solution of the present invention is: the detection method for the high energy flux density corresponding to the rated power of the xenon lamp condensing unit is

[0010] Set the power of the xenon lamp condensing unit, and place the water-cooled Lambert target at the focal position of the high energy flux solar radiation simulator;

[0011] Turn on the high energy flux solar radiation simulator, and project a single spot or superimposed spots onto the water-cooled Lambert target;

[0012] Use a CCD camera to obtain the gray-scale distribution of the spot, and at the same time use a heat flux sensor to collect the heat flux density values at different positions on the spot, and calibrate the gray-scale of the spot to obtain the heat flux density distribution of the spot.

[0013] Repeat the above steps, set different powers of the xenon lamp condensing unit, and obtain the corresponding spot heat flux density distribution.

[0014] A further technical solution of the present invention is that the detection device for the high-energy flux density corresponding to the rated power of the xenon lamp condensing unit is a spot heat flux distribution measuring instrument. The spot heat flux distribution measuring instrument includes a water-cooled Lambert target and a heat flux sensor disposed thereon. The water-cooled Lambert target is installed on the optical platform through an electric slide and a three-dimensional adjustment platform, and the spatial position of the water-cooled Lambert target is adjusted through the electric slide and the three-dimensional adjustment platform; and the water-cooled Lambert target is communicated with the second water-cooling system, and the temperature of the water-cooled Lambert target is controlled through water circulation; the heat flux sensor sends the collected spot information to the host computer to record and match the corresponding power.

[0015] A further technical solution of the present invention is that the high-energy flux solar radiation simulator includes an equipment housing and a plurality of xenon lamp condensing units installed therein through brackets, and an air-cooling system and a first water-cooling system are provided on the equipment housing to cool and control the temperature of the xenon lamp condensing units; the xenon lamp condensing unit includes a condenser with a hemispherical housing structure and a xenon light source and a trigger installed therein, and the xenon light source is started through the trigger.

[0016] A further technical solution of the present invention is that the single-point temperature measurement and the full-field temperature distribution measurement are respectively completed by a thermocouple and an infrared thermal imager; the thermocouple is disposed on the back of the experimental flat plate to be measured; the optical lens of the infrared thermal imager faces the back of the experimental flat plate to be measured and can completely irradiate the back of the experimental flat plate to be measured.

[0017] A measuring method for a thermal protection material property detection system based on xenon lamp heating is as follows:

[0018] Install the experimental flat plate to be measured on the experimental table through a fixture;

[0019] Place the high-energy flux solar radiation simulator, the thermocouple and the infrared thermal imager at the set positions respectively;

[0020] Place a baffle between the high-energy flux solar radiation simulator and the experimental flat plate to be measured;

[0021] Start the xenon lamp condensing unit and adjust the power to the set value;

[0022] When the xenon lamp condensing unit is loaded to the target heat flux, remove the baffle;

[0023] Irradiate for 40 s and then turn off the light source, and continue to monitor the temperature of the back of the specimen until the highest temperature appears;

[0024] Save the data of the thermocouple and the infrared thermal imager, and the experimental process ends.

[0025] A simulation method for detecting the characteristics of a thermal protection material based on xenon lamp heating, the specific steps are as follows:

[0026] Heat flux data extraction: Establish a xenon lamp model through ray simulation software, simulate the heat flux distribution at the focal point of the xenon lamp light source, and extract the target heat flux data;

[0027] Three-dimensional model construction: Establish a three-dimensional geometric model of the protective sleeve specimen in a multi-physics field simulation software. The specimen is a multi-layer structure, including at least one phase change layer, and set the material properties of each layer;

[0028] Boundary condition and phase change parameter setting: Set the boundary conditions of the solid heat transfer module, including the initial temperature, the surface radiation condition to the environment, and load the extracted target heat flux data as a boundary heat source onto the specimen surface; Set the phase change parameters for the phase change layer separately, including the phase change temperature, phase change interval, and latent heat, and define the phase change time and enthalpy change parameters through the "irreversible transformation" function;

[0029] Transient simulation and verification: Conduct transient heat transfer simulation and set the research time; After the simulation is completed, extract the temperature distribution data on the back of the specimen and compare it with the experimental measurement results. If the error < 10%, it is determined that the simulation model is valid.

[0030] A further technical solution of the present invention is: The comparison parameters are set as: phase change temperature 542K, phase change interval 73.6K, latent heat 461060J / kg; Combining the "irreversible transformation" function, define the phase change time as the critical moment when the phase change layer is completely phase-changed in the simulation.

[0031] A further technical solution of the present invention is: The specimen is a four-layer composite structure, including a quartz silicon coating, a silicone coating, an E-glass fiber layer, and an aramid felt layer, wherein the second silicone coating is the phase change layer.

[0032] A thickness optimization method for a thermal protection material based on xenon lamp heating, the specific steps are as follows:

[0033] Conduct transient heat transfer simulation on the protective sleeve specimen through multi-physics field simulation software to obtain the highest temperature distribution data on the back of the specimen;

[0034] Compare the highest temperature on the back of the specimen in the simulation result with a preset threshold;

[0035] If the highest temperature on the back of the specimen exceeds the preset threshold and the phase change layer is not completely phase-changed, increase the thickness of the last non-phase change layer; If the phase change layer is completely phase-changed, increase the thickness of the phase change layer;

[0036] If the highest temperature is lower than the preset threshold and the phase change layer is not completely phase-changed, reduce the thickness of the phase change layer; If the phase change layer is completely phase-changed, reduce the thickness of the last non-phase change layer;

[0037] Based on the adjusted thickness configuration, the simulation and judgment are re-executed until the maximum temperature on the back of the specimen reaches the preset threshold, the iterative optimization is completed, and the final thickness is output as the optimal configuration.

[0038] Beneficial Effects

[0039] The beneficial effects of the present invention are as follows: the present invention uses a high-energy flux xenon lamp system, a composite detection method and an experiment-simulation collaborative optimization mechanism. The composite detection method uses a combination of thermocouple + thermal imager, which can accurately obtain a single-point temperature value while also obtaining a temperature distribution within a certain range, which can reduce temperature errors to a certain extent and improve the accuracy of experimental data measurement. In the experiment-simulation combination, simulation can predict results before the experiment, reduce the number and scale of experiments, and thus reduce costs. For expensive or difficult experiments, simulation provides a cost-effective alternative. Simulation can be used to optimize the design and find the best performance configuration by simulating different design schemes. The specific effects are analyzed as follows:

[0040] 1. Improved high energy flow experimental capability. Xenon lamp system provides peak value of more than 3000kW / m 2 The energy flux density covers the extreme thermal environment testing requirements in the aerospace field, breaks through the limitations of traditional quartz lamps in medium and low energy flux experiments, and supports high energy flux material performance verification.

[0041] 2. Optimization of temperature detection accuracy. The combination of thermocouples (single-point precise measurement) and thermal imagers (full-field distributed monitoring) reduces the comprehensive error by more than 30%, significantly improving the comprehensiveness and accuracy of temperature data collection.

[0042] 3. Reduced R&D costs and cycles. The experiment and simulation collaborative optimization mechanism (error <10%) reduces the number of physical experiment iterations by more than 50%, which is especially suitable for high-risk or expensive experimental scenarios, saving time and economic costs.

[0043] 4. Improved material design efficiency. Through simulation prediction and optimization iteration (such as adjustment of phase change layer thickness), the optimal material configuration (such as lightweight goal) can be quickly determined, the R&D cycle can be shortened, and thermal protection performance and material utilization can be improved.

[0044] 5. Enhanced simulation capabilities for complex thermal behavior. Supports multi-physics field coupling simulation (such as transient heat transfer, phase change, and ablation simulation in COMSOL), providing a theoretical basis for the response of materials under extreme conditions and reducing the risk of trial and error.

[0045] 6. Standardization and scalability. The modular design of the system (heat flow detection, experiment, simulation) supports standardized operation procedures and lowers the technical threshold; it is compatible with a variety of thermal protection materials (ceramic matrix composites, phase change materials, etc.) and multi-field applications (aerospace, nuclear energy).

[0046] 7. Lightweight and performance balance. The optimization method is guided by the back surface temperature threshold (such as ≤ 100 °C). By dynamically adjusting the thickness of the phase change layer and the non-phase change layer, the precise balance between material lightweight and thermal protection performance is achieved, meeting the weight reduction requirements of the aircraft. Description of the Drawings

[0047] Figure 1 It is a schematic diagram of the thermal protection material property detection system based on xenon lamp heating in the embodiment of the present invention;

[0048] Figure 2 It is a schematic diagram of the high-energy flux solar radiation simulator in the embodiment of the present invention;

[0049] Figure 3 It is a schematic diagram of the focal position of the xenon lamp light source in the embodiment of the present invention;

[0050] Figure 4 It is a schematic diagram of the CCD camera in the embodiment of the present invention;

[0051] Figure 5 It is a schematic diagram of the spot heat flux distribution measuring instrument in the embodiment of the present invention;

[0052] Figure 6 It is a diagram of the spot superposition result of the xenon lamp superimposed electric power 2 + 2 + 2 in the embodiment of the present invention;

[0053] Figure 7 It is a diagram of the spot superposition result of the xenon lamp superimposed electric power 3 + 3 + 3 in the embodiment of the present invention;

[0054] Figure 8 It is a diagram of the spot superposition result of the xenon lamp superimposed electric power 4 + 4 + 4 in the embodiment of the present invention;

[0055] Figure 9 It is a diagram of the spot superposition result of the xenon lamp superimposed electric power 5 + 5 + 5 in the embodiment of the present invention;

[0056] Figure 10 It is a diagram of the spot superposition result of the xenon lamp superimposed electric power 6 + 6 + 6 in the embodiment of the present invention;

[0057] Figure 11 It is a flowchart of a simulation method for detecting the properties of a thermal protection material based on xenon lamp heating in the embodiment of the present invention;

[0058] Figure 12 It is a calculation diagram of the spot heat flux distribution in the embodiment of the present invention;

[0059] Figure 13 It is a measurement schematic diagram of a thermal protection material property detection system based on xenon lamp heating in the embodiment of the present invention;

[0060] Figure 14 It is the xenon lamp model diagram in TracePro in the invention embodiment;

[0061] Figure 15 It is the simulated heat flux distribution in the invention embodiment;

[0062] Figure 16 It is the phase change material setting in the invention embodiment;

[0063] Figure 17 It is the irreversible transformation setting in the invention embodiment;

[0064] Figure 18 It is the phase change property of the phase change material in the invention embodiment;

[0065] Figure 19 It is the phase change effect setting of the "phase change material" in the invention embodiment;

[0066] Figure 20 It is the phase change time diagram in the invention embodiment;

[0067] Figure 21 It is the comparison diagram of the back surface temperature of the experiment and simulation flat plates in the invention embodiment;

[0068] Figure 22 It is the simulation step flow chart in the invention embodiment.

[0069] Explanation of reference numerals: 1. High-energy solar radiation simulator, 11. Equipment housing, 12. Condensing unit support, 13. Trigger, 14. Condensing mirror, 15. Xenon light source, 16. Air cooling system, 17. Cable; 18. First water cooling system; 2. Spot heat flux distribution measuring instrument, 21. Water-cooled Lambert target, 22. Heat flux sensor, 23. Second water cooling system, 231. Water-cooled outlet, 232. Water-cooled inlet, 24. Electric slide table, 25. Three-dimensional adjustment platform, 26. Optical platform, 27. Stepper motor, 28. CCD camera, 29. Computer; 3. Experimental flat plate; 4. Thermal imager. Detailed implementation manners

[0070] The embodiments described below by referring to the accompanying drawings are exemplary and are intended to explain the present invention and should not be construed as limiting the present invention.

[0071] Based on the problems of insufficient energy flux, single temperature measurement, and low optimization efficiency in traditional thermal protection detection, the present invention provides a detection system for the characteristics of thermal protection materials based on xenon lamp heating, including a high-energy flux solar radiation simulator; the high-energy flux solar radiation simulator includes a plurality of xenon lamp condensing units that simulate solar radiation, and the regulation of high-energy flux density is achieved by adjusting the power of the xenon lamp condensing units, and light irradiation and temperature measurement are performed on the test experimental flat plate placed at the focal position of the high-energy flux solar radiation simulator; the temperature measurement adopts a combination of single-point temperature measurement and full-field temperature distribution measurement, and the obtained temperature measurement data is sent to the host computer for feedback.

[0072] The high-energy flux solar radiation simulator includes an equipment outer cover and a plurality of xenon lamp condensing units installed therein through brackets, and an air cooling system and a first water cooling system are arranged on the equipment outer cover to cool and control the temperature of the xenon lamp condensing units; the xenon lamp condensing unit includes a condenser with a hemispherical shell structure and a xenon light source and a trigger installed therein, and the xenon light source is started by the trigger.

[0073] The single-point temperature measurement and the full-field temperature distribution measurement are respectively completed by a thermocouple and an infrared thermal imager; the thermocouple is arranged on the back of the test experimental flat plate; the optical lens of the infrared thermal imager faces the back of the test experimental flat plate and can completely irradiate the back of the test experimental flat plate.

[0074] The above technical solutions are further described below in conjunction with the drawings and examples:

[0075] In one embodiment, a detection system for the characteristics of thermal protection materials based on xenon lamp heating in this embodiment includes three parts: a heat flux detection module, an experimental module, and a simulation module. The temperature monitoring method of the present invention adopts a combination of a thermocouple and an infrared thermal imager, which can accurately obtain the single-point temperature value and also obtain the temperature distribution within a certain range, and can reduce the temperature error to a certain extent and improve the accuracy of experimental data measurement. The present invention combines experiment and simulation. Simulation can predict the results before the experiment, reduce the number and scale of experiments, and thus reduce costs. For expensive or difficult experiments, simulation provides a cost-effective alternative. Simulation can be used to optimize the design, and by simulating different design schemes, the best performance configuration can be found.

[0076] Specifically, refer to Figure 2As shown in the figure, the heat flux detection module includes a high-energy solar radiation simulator 1 (abbreviation: xenon lamp device), a cooling pump, a spot heat flux distribution measuring instrument 2, and a computer 29. The xenon lamp device consists of 3 xenon lamp condensing units, mainly including a condenser lens 14, a xenon lamp light source 15, a trigger 13, an air cooling system 16, a first water cooling system 18, a condensing unit support 12, a cable 17, and an equipment housing 11. The rated electric power of each xenon lamp condensing unit is 6 kW, the total rated electric power of the system is 18 kW, the rated radiation power of the focused spot is 5.4 kW, and the peak value of the spot energy flux density > 3000 kW / m2. The distance between the light source focus and the front edge of the equipment is 360 mm, as Figure 3 shown.

[0077] Specifically, referring to Figure 4 , 5 shown, the spot heat flux distribution measuring instrument 2 (Flux Mapping System) is used to measure the heat flux density distribution of the focused sunlight spot with a high convergence ratio. The spot heat flux distribution measuring instrument 2 mainly consists of a water-cooled Lambert target 21, a heat flux sensor 22, a data acquisition module, a CCD camera 28, an electric slide table 24, a three-dimensional adjustment platform 25, an optical platform 26, and a control box. The water-cooled Lambert target 21 is installed on the optical platform 26 through the electric slide table 24 and the three-dimensional adjustment platform 25, and the spatial position of the water-cooled Lambert target 21 is adjusted through the electric slide table 24 and the three-dimensional adjustment platform 25, where the electric slide table 24 is controlled by a stepping motor 27; and the water-cooled Lambert target 21 is connected to the second water cooling system 23, and the temperature of the water-cooled Lambert target 21 is controlled through water circulation; the heat flux sensor 22 sends the collected spot information to the host computer, records and matches the corresponding power. Referring to Figure 1 shown, the measurement principle is: First, use the CCD camera 28 to take a picture of the spot on the water-cooled Lambert target 21 to obtain the gray-scale distribution of the spot; then use the heat flux sensor 22 to collect the heat flux density values at different positions on the spot, calibrate the gray-scale of the spot, and thus obtain the heat flux density distribution of the spot.

[0078] Specifically, the spot measurement results of the three xenon lamps at the electric power of 2 - 6 kW are as follows:

[0079]

[0080]

[0081] Specifically, the spot superposition results of the three xenon lamps at different powers are as follows:

[0082]

[0083] Referring to Figures 6 to 10 shown, they are the measurement results of the spot superposition of the three xenon lamps at different electric powers respectively.

[0084] In one embodiment, with reference to Figure 11 As shown, for the measurement method of a thermal protection material property detection system based on xenon lamp heating in this embodiment, when the material and layer structure of a protection kit have been determined and the optimal thickness of each layer of this protection cover needs to be obtained, this detection system can be used to obtain it. First, the heat flux for the experiment test needs to be determined, and this step is carried out in the heat flux detection template. After obtaining the experimental target heat flux in the spot heat flux distribution measuring instrument, the heat flux distribution can be read on the computer, as Figure 12 shown, and record the xenon lamp power at this time. The specific steps are as follows:

[0085] Step 1: Install the experimental plate to be tested on the experimental table through a fixture;

[0086] Step 2: Place the high-energy flux solar radiation simulator, thermocouple, and thermal imager at the set positions respectively;

[0087] Step 3: Place a baffle between the high-energy flux solar radiation simulator and the experimental plate to be tested;

[0088] Step 4: Start the xenon lamp condensing unit and adjust the power to the set value;

[0089] Step 5: When the xenon lamp condensing unit is loaded to the target heat flux, remove the baffle;

[0090] Step 6: After irradiating for 40 s, turn off the light source, and continue to monitor the temperature on the back of the specimen until the highest temperature appears;

[0091] Step 7: Save the data of the thermocouple and thermal imager, and the experiment process ends.

[0092] In one embodiment, a certain aviation protection cover specimen is detected and optimized. Since the xenon lamp has been calibrated for heat flux in advance, the corresponding power can be directly adjusted according to the parameter table. As shown in Table 1 below, Experiment No. 1 xenon lamp is selected, the electric power of the xenon lamp is 3017 w, and the peak value of its spot heat flux density is 615.44 kW / m2.

[0093] Table 1 Measurement Results of No. 1 Xenon Lamp Spot

[0094]

[0095] Preferably, the protective sleeve test piece is a rectangular flat plate with a width of 120 mm, a length of 200 mm, and a height of 4.5 mm. The structure is divided into four layers, which are, from top to bottom, a quartz silicon coating, a silicone coating, an E-glass fiber layer, and an aramid felt layer, with thicknesses of 0.2 mm, 3.1 mm, 0.2 mm, and 1 mm, respectively. According to the experimental procedure, first set up the experimental bench and arrange the thermocouples on the back of the protective sleeve test piece in advance. Place the protective sleeve on the fixture at the focal position directly in front of the xenon lamp, and place the thermal imager at an appropriate distance directly behind the protective sleeve so that the back of the test piece can be completely irradiated. The relative positions of the experimental equipment, the test piece, the thermocouples, and the thermal imager are as shown in Figure 13 shown. After the test piece and the like are arranged, start the xenon lamp equipment. Before turning on the xenon light source, the water cooling and air cooling need to be turned on first. After cooling for a period of time, turn on the No. 1 xenon lamp light source, and quickly rotate the power button to the corresponding value (since it takes some time to load to the target heat flux, a baffle can be added between the test piece and the light source, and the baffle is removed when the light source is loaded to the target heat flux, and then start timing). Irradiate for 40 s and then turn off the light source, and continue to monitor the temperature on the back of the test piece until the highest temperature appears. Save the thermocouple and thermal imaging data, and the experimental process ends.

[0096] In one embodiment, as shown in Figure 18 shown, a simulation method for detecting the characteristics of a thermal protection material based on xenon lamp heating in this embodiment is as follows:

[0097] Step 1: Heat flux data extraction: Establish a xenon lamp model through ray simulation software (as shown in Figure 14 shown), simulate the heat flux distribution at the focal point of the xenon lamp light source, and extract the target heat flux data;

[0098] Step 2: Three-dimensional model construction: Establish a three-dimensional geometric model of the protective sleeve test piece in a multi-physics field simulation software. The test piece is a multi-layer structure, including at least one phase change layer, and set the material properties of each layer;

[0099] Step 3: Boundary condition and phase change parameter setting: Set the boundary conditions of the solid heat transfer module, including the initial temperature, the surface radiation condition to the environment, and load the extracted target heat flux data as a boundary heat source onto the surface of the test piece; separately set the phase change parameters for the phase change layer, including the phase change temperature, the phase change interval, and the latent heat, and define the phase change time and enthalpy change parameters through the "irreversible transformation" function;

[0100] Step 4: Transient simulation and verification: Conduct a transient heat transfer simulation (the simulated heat flux distribution is as shown in Figure 15 shown), and set the research time; after the simulation is completed, extract the temperature distribution data on the back of the test piece and compare it with the experimental measurement results. If the error < 10%, it is determined that the simulation model is valid.

[0101] Specifically, the extracted heat flux is imported into COMSOL to establish a three-dimensional model of the protective sleeve specimen. The solid flow and heat transfer module is selected for transient simulation. The specific process of the simulation is as follows:

[0102] First, establish the corresponding physical model. Select geometry to establish the protective sleeve specimen model (width 120 mm, length 200 mm, height 4.5 mm). In this operation, set the number of layers to 4 and set the material properties of each layer.

[0103] Then, set the model boundary conditions. The solid domain is set to all (for different models, it needs to be determined according to the actual situation. For example, in this example, the second layer is the phase change layer, and the second layer needs to be set as the phase change layer separately and the phase change parameters are set). Set the initial value of the entity temperature (room temperature in this simulation); set the surface radiation to the environment. Select all outer surfaces for the surface, and set the environmental temperature to room temperature; set the boundary heat source boundary to the first layer of the model, and the size is the corresponding heat flux extracted in TracePro.

[0104] Preferably, for the phase change related settings: Select the second layer as the phase change layer and set the relevant phase change operations. (In COMSOL, there are phase change materials and irreversible transformations. Here, both the phase change material and irreversible transformation settings are required). The related settings of "phase change material" are as Figure 16 shown, including the settings of phase change temperature, transformation interval, and latent heat; the related settings of irreversible transformation are as Figure 17 shown, including transformation temperature, transformation time, and enthalpy change (latent heat). Generally, the phase change temperature, transformation interval, and enthalpy change can be obtained through testing by relevant institutions. For example, the material parameters in this example are as Figure 18 shown. Due to the timeliness of the boundary heat source, the temperature of the phase change layer will first increase and then decrease. Setting the "phase change material" operation for the phase change layer will result in the reversibility of the phase change, as Figure 19 shown.

[0105] To avoid this situation, this simulation method provides a setting mainly based on "irreversible transformation" and supplemented by "phase change material" to better simulate and analyze. The difference between the "irreversible transformation" and "phase change material" settings lies in one being the phase change time (time span) and the other being the phase change interval (temperature span). The parameters given by the testing institution are only the phase change interval, and the phase change time needs to be obtained through the "phase change material". The specific method: First, only set the "phase change material" and set the parameters according to Figure 18 which is shown in Table 2. After the following operations are set, click "Study" to perform the simulation. After the simulation is completed, view the results: Select volume average in the derived values, and change the expression setting in it to "ht2.alpha12" (this expression can be found in the variable area of the phase indicator, phase 2 in the "phase change material equation view"), select the phase change layer for the region, calculate and view the data, as Figure 20As shown, it can be seen that the phase change reaches the maximum value at 41 s, and the time corresponding to this point is the phase change time. Take the maximum phase change moment as the phase change time, turn off the "phase change material" setting, set the "irreversible transformation", and the phase change related settings are completed.

[0106] Table 2 Phase change parameters

[0107] Parameter Phase transition temperature / K Phase transition interval / K Latent heat (J / kg) Value 542 73.6 461060

[0108] After that, after the boundary conditions are set, establish the corresponding model grid (the physical field control grid provided by COMSOL can be used), set the study as a transient study, and the study time is 500 s.

[0109] Finally, after the simulation is completed, post-processing is carried out to view the temperature distribution cloud map at the moment of the highest temperature on the back. After the simulation, post-processing is carried out, and the simulation data is compared with the experimental temperature data. When the error between the simulation data and the experimental data is less than 10%, the feasibility of the simulation can be proved.

[0110] In one embodiment, with reference to Figure 22 As shown, a method for optimizing the thickness of a thermal protection material based on xenon lamp heating in this embodiment is as follows:

[0111] Step 1: Perform transient heat transfer simulation on the protective sleeve specimen through a multi-physics simulation software to obtain the highest temperature distribution data on the back of the specimen;

[0112] Step 2: Compare the highest temperature on the back of the specimen in the simulation result with a preset threshold;

[0113] If the highest temperature on the back of the specimen exceeds the preset threshold and the phase change layer has not fully undergone phase change, increase the thickness of the last non-phase change layer; if the phase change layer has fully undergone phase change, increase the thickness of the phase change layer;

[0114] If the highest temperature is lower than the preset threshold and the phase change layer has not fully undergone phase change, reduce the thickness of the phase change layer; if the phase change layer has fully undergone phase change, reduce the thickness of the last non-phase change layer;

[0115] Step 3: Based on the adjusted thickness configuration, re-perform the simulation and determination until the highest temperature on the back of the specimen reaches the preset threshold, complete the iterative optimization, and output the final thickness as the optimal configuration.

[0116] Specifically, with reference to Figure 21 As shown, overall, Figure 21The (a) and (b) regions of the highest temperature distribution are relatively similar, and the difference in the highest temperature is within 10°C. Compared with Figure (b), the difference in the highest temperature at the corresponding position in Figure (a) does not exceed 10°C, meeting the feasibility requirements. Therefore, simulation can be used to optimize the protection plate. That is, the simulation can change the boundary conditions for further optimization to meet the thermal protection requirements; otherwise, adjust the simulation parameters and repeat the simulation process.

[0117] Optimization process: (The optimization goal is lightweight, that is, to meet the thermal protection requirements on the premise of light mass and thin thickness. In this test piece, the second phase change layer has a greater impact on the mass, and the last layer is the thickest. Therefore, the main way is to change the second phase change layer and the auxiliary way is to change the last layer to achieve the optimization goal). Assume that the highest temperature on the back of the plate is required not to exceed 100°C. According to the verified simulation results, check if the highest temperature on the back of the plate is greater than 100°C, and check the phase change degree of the second phase change layer. If it is not completely phase-changed, increase the thickness of the last layer (increase it with a specific step thickness); if it is completely phase-changed, increase the thickness of the phase change layer and keep the thickness of the last layer unchanged. Keep other conditions unchanged and re-run the simulation to check the highest temperature on the back of the plate until it does not exceed 100°C; According to the verified simulation results, check if the highest temperature on the back of the plate is less than 100°C, and check the phase change degree of the second phase change layer. If it is not completely phase-changed, reduce the thickness of the second phase change layer; if it is completely phase-changed, reduce the thickness of the last layer. Keep other conditions unchanged and re-run the simulation to check the highest temperature on the back of the plate until it reaches 100°C; When the above simulation finally stops, the thickness of the plate is the optimal thickness.

[0118] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention without departing from the principles and purposes of the present invention.

Claims

1. A detection system for the characteristics of a thermal protection material based on xenon lamp heating, characterized in that: It includes a high-energy flux solar radiation simulator; the high-energy flux solar radiation simulator includes multiple xenon lamp condensing units for simulating solar radiation, and the regulation of high-energy flux density is achieved by adjusting the power of the xenon lamp condensing units, and the test experimental plate placed at the focal position of the high-energy flux solar radiation simulator is illuminated and temperature measured; The temperature measurement adopts a combination of single-point temperature measurement and full-field temperature distribution measurement, and the obtained temperature measurement data is sent to the upper computer for feedback.

2. The thermal protection material property detection system based on xenon lamp heating according to claim 1, characterized in that: The detection method for the high-energy flux density corresponding to the rated power of the xenon lamp condensing unit is as follows: Set the power of the xenon lamp condensing unit, and place the water-cooled Lambert target at the focal position of the high-energy flux solar radiation simulator; Turn on the high-energy flux solar radiation simulator, and project a single spot or superimposed spots onto the water-cooled Lambert target; Use a CCD camera to obtain the gray-scale distribution of the spot, and at the same time use a heat flux sensor to collect the heat flux density values at different positions on the spot, and calibrate the gray-scale of the spot to obtain the heat flux density distribution of the spot; Repeat the above steps, set different powers of the xenon lamp condensing unit, and obtain the corresponding spot heat flux density distributions.

3. The characteristic detection system of a thermal protection material based on xenon lamp heating according to claim 2, wherein: The detection equipment for the high-energy flux density corresponding to the rated power of the xenon lamp condensing unit is a spot heat flux distribution measuring instrument. The spot heat flux distribution measuring instrument includes a water-cooled Lambert target and a heat flux sensor arranged thereon. The water-cooled Lambert target is installed on the optical platform through an electric slide and a three-dimensional adjustment platform, and the spatial position of the water-cooled Lambert target is adjusted through the electric slide and the three-dimensional adjustment platform; and the water-cooled Lambert target is connected to the second water-cooling system, and the temperature of the water-cooled Lambert target is controlled through water circulation; the heat flux sensor sends the collected spot information to the upper computer, records and matches the corresponding power.

4. The characteristic detection system of a thermal protection material based on xenon lamp heating according to claim 1, wherein: The high-energy flux solar radiation simulator includes an equipment outer cover and multiple xenon lamp condensing units installed therein through brackets, and an air-cooling system and a first water-cooling system are arranged on the equipment outer cover to cool and control the temperature of the xenon lamp condensing units; the xenon lamp condensing unit includes a condenser with a hemispherical shell structure and a xenon light source and a trigger installed therein, and the xenon light source is started through the trigger.

5. The characteristics detection system of a thermal protection material based on xenon lamp heating according to claim 1, characterized in that: The single-point temperature measurement and full-field temperature distribution measurement are respectively completed by a thermocouple and a thermal imager; the thermocouple is arranged on the back of the test experimental plate; the optical lens of the thermal imager is opposite to the back of the test experimental plate and can completely irradiate the back of the test experimental plate.

6. A measurement method for a detection system of the characteristics of a thermal protection material based on xenon lamp heating according to any one of claims 1-5, characterized in that The specific steps are as follows: Install the test experimental plate on the experimental table through a fixture; Place the high-energy flux solar radiation simulator, the thermocouple and the thermal imager at the set positions respectively; Place a baffle between the high-energy flux solar radiation simulator and the test experimental plate; Start the xenon lamp condensing unit and adjust the power to the set value; When the xenon lamp condensing unit is loaded to the target heat flux, remove the baffle; Irradiate for 40 s and turn off the light source, and continue to monitor the temperature on the back of the specimen until the highest temperature appears; Save the data of the thermocouple and the thermal imager, and the experimental process ends.

7. A simulation method for detecting the characteristics of a thermal protection material based on xenon lamp heating, characterized in that The specific steps are as follows: Heat flux data extraction: Establish a xenon lamp model through ray simulation software, simulate the heat flux distribution at the focal point of the xenon light source, and extract the target heat flux data; 3D model construction: Establish a 3D geometric model of the protective sleeve specimen in multi-physics simulation software. The specimen is a multi-layer structure, including at least one phase change layer, and set the material properties of each layer. Boundary condition and phase change parameter setting: Set the boundary conditions of the solid heat transfer module, including the initial temperature, the surface radiation condition to the environment, and load the extracted target heat flux data as a boundary heat source onto the specimen surface; Set the phase change parameters for the phase change layer separately, including the phase change temperature, phase change interval, and latent heat, and define the phase change time and enthalpy change parameters through the "irreversible transformation" function. Transient simulation and verification: Conduct transient heat transfer simulation and set the research time; After the simulation is completed, extract the temperature distribution data on the back of the specimen and compare it with the measurement results of the measurement method described in claim 6. If the error < 10%, it is determined that the simulation model is valid.

8. The simulation method for detecting the characteristics of a thermal protection material based on xenon lamp heating according to claim 7, wherein: The phase change parameters are set as follows: phase change temperature 542K, phase change interval 73.6K, latent heat 461060J / kg; Combining the "irreversible transformation" function, define the phase change time as the critical moment when the phase change layer completely undergoes phase change in the simulation.

9. The simulation method for detecting the characteristics of a thermal protection material based on xenon lamp heating according to claim 7, characterized in that: The specimen is a four-layer composite structure, including a quartz-silicon coating, a silicone coating, an E-glass fiber layer, and an aramid felt layer, where the second silicone coating is the phase change layer.

10. A method for optimizing the thickness of a thermal protection material based on xenon lamp heating, characterized in that: Perform transient heat transfer simulation on the protective sleeve specimen through multi-physics simulation software to obtain the highest temperature distribution data on the back of the specimen. Compare the highest temperature on the back of the specimen in the simulation result of the simulation method described in claim 7 with a preset threshold. If the highest temperature on the back of the specimen exceeds the preset threshold and the phase change layer has not completely undergone phase change, increase the thickness of the last non-phase change layer; If the phase change layer has completely undergone phase change, increase the thickness of the phase change layer. If the highest temperature is lower than the preset threshold and the phase change layer has not completely undergone phase change, reduce the thickness of the phase change layer; If the phase change layer has completely undergone phase change, reduce the thickness of the last non-phase change layer. Based on the adjusted thickness configuration, re-perform the simulation and determination until the highest temperature on the back of the specimen reaches the preset threshold, complete the iterative optimization, and output the final thickness as the optimal configuration.

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