Integrated testing system and method for thermal protection material performance

Abstract

The embodiment of the present invention provides an integrated test system and method for the performance of thermal protection materials, which are used to detect the performance of aircraft thermal protection materials. The integrated test system for the performance of thermal protection materials includes a control system, a thermal environment simulation system and a detection system, and the control system is respectively connected to the thermal environment simulation system and the detection system in communication. The control system is used to determine the preset parameters of the flight conditions, and determine the aerodynamic thermal data according to the preset parameters of the flight conditions, and control the thermal environment simulation system. The thermal environment simulation system is used to simulate the thermal environment of the flight process. The detection system is used to detect the thermal physical parameters of the thermal protection material to be tested, and transmit the thermal physical parameter detection results to the control system. The integrated test system and method for the performance of thermal protection materials of the embodiment of the present invention is an integrated unsteady test, which simulates the actual flight process, and has a simple test process, high efficiency and high test result accuracy.

Description

Technical Field

[0001] The present invention relates to the technical field of material performance testing equipment and methods, and in particular to a thermal protection material performance integrated testing system and method. Background Art

[0002] Hypersonic aircraft will experience the atmosphere when in flight, which will generate aerodynamic heating on the surface of the aircraft, causing the temperature of the surface and interior of the aircraft to rise. When the temperature is too high, the instruments and equipment of the aircraft will not work properly. The key to solving the "thermal barrier" problem is to reasonably design a thermal protection system to ensure the normal operation of the aircraft. The goal of aircraft thermal protection is to ensure that the internal structure of the aircraft is within a safe temperature range, and its design indicator is that the internal temperature of the structure does not exceed the allowable temperature.

[0003] When designing a thermal protection system, it is necessary to reasonably select thermal protection materials according to needs. When selecting appropriate thermal protection materials, it is necessary to conduct thermal physical property tests on different thermal protection materials separately.

[0004] In the process of realizing the present invention, the inventors found that there are at least the following problems in the prior art: the performance test of thermal protection materials in the prior art is mostly a steady-state test, that is, the performance test of the thermal protection material to be tested is carried out under a specific environment. This test method requires separate tests when testing multiple parameters, which is time-consuming and cumbersome. In addition, since each parameter is tested separately, there are differences in the measurement environment between the parameters, and there is a lack of coupling changes and correlations between the parameters. At the same time, this test method does not take into account the state of the thermal environment of the aircraft changing over time in the flight state. There is a certain difference between its test results and the actual use results, which easily leads to the situation that the design results cannot meet the normal operation of the aircraft. Summary of the invention

[0005] In view of this, an object of an embodiment of the present invention is to provide an integrated testing system and method for thermal protection material performance, so as to solve the problems existing in the prior art such as cumbersome testing process, long time consumption, and poor accuracy of test results.

[0006] In a first aspect, an embodiment of the present invention provides an integrated thermal protection material performance testing system for detecting the performance of aircraft thermal protection materials, including a control system, a thermal environment simulation system and a detection system, wherein the control system is respectively connected to the thermal environment simulation system and the detection system in communication;

[0007] The control system is used to determine the preset parameters of the flight condition, determine the aerodynamic thermal data according to the preset parameters of the flight condition, and control the thermal environment simulation system according to the aerodynamic thermal data;

[0008] The thermal environment simulation system is used to simulate the thermal environment of the flight process consistent with the aerodynamic thermal data, and to heat the thermal protection material to be tested;

[0009] The detection system is used to detect the thermal physical property parameters of the thermal protection material to be tested under the thermal environment, and transmit the thermal physical property parameter detection results to the control system.

[0010] Furthermore, the thermophysical property parameters include one or more of emissivity, specific heat capacity, thermal diffusion coefficient, thermal conductivity, thermal resistance and burnout.

[0011] Furthermore, the control system includes a host computer, a slave computer and a data acquisition module;

[0012] The host computer is used to determine the preset parameters of the flight condition, and determine the aerodynamic thermal data according to the preset parameters of the flight condition;

[0013] The lower computer is used to control the thermal environment simulation system and the detection system;

[0014] The data acquisition module is used to receive information transmitted by the thermal environment simulation system and the detection system, and transmit the information to the host computer.

[0015] Furthermore, the thermal environment simulation system includes a heater, a sensor and a heat flow meter; the heater is used to heat the thermal protection material to be tested, and a test position is provided on the heater, and the test position is used to place the thermal protection material to be tested; the sensor is used to detect the temperature of the thermal protection material to be tested, and transmit the detection result to the control system; the heat flow meter is used to detect the heat flow of the thermal protection material to be tested, and transmit the detection result to the control system.

[0016] Furthermore, the sensor includes a front temperature sensor, a back temperature sensor, a layered temperature sensor and a ranging sensor; the thermal protection material to be tested includes a front side, a back side and a plurality of layers between the front side and the back side, the front side is a side close to the heater, and the back side is a side away from the heater; the front temperature sensor is used to measure the temperature of the front side; the back temperature sensor is used to measure the temperature of the back side; the layered temperature sensor is used to measure the temperature of each layer of the thermal protection material to be tested; the ranging sensor is used to measure the thickness of the thermal protection material to be tested to obtain the ablation amount.

[0017] Furthermore, the detection system includes a differential scanning calorimeter, a flash thermal conductivity meter and a Fourier transform infrared spectrometer; the differential scanning calorimeter is used to detect the specific heat capacity of the thermal protection material to be tested; the flash thermal conductivity meter is used to detect the thermal diffusion coefficient of the thermal protection material; and the Fourier transform infrared spectrometer is used to detect the emissivity of the thermal protection material.

[0018] In a second aspect, an embodiment of the present invention provides a thermal protection material performance integrated testing method for a thermal protection material performance integrated testing system, comprising the following steps:

[0019] Determine the preset parameters of flight conditions;

[0020] Determining aerodynamic thermal data according to preset parameters of the flight condition;

[0021] Simulating the thermal environment of the flight process according to the aerodynamic thermal data, heating the thermal protection material to be tested, and detecting the thermal physical property parameters of the thermal protection material to be tested by the thermal protection material performance integrated test system to obtain the thermal physical property parameter detection results;

[0022] The thermal protection material performance integrated testing system comprises a control system, a thermal environment simulation system and a detection system, wherein the control system is respectively connected to the thermal environment simulation system and the detection system in communication;

[0023] The control system is used to determine flight condition preset parameters, determine aerodynamic thermal data according to the flight condition preset parameters, and control the thermal environment simulation system according to the aerodynamic thermal data;

[0024] The thermal environment simulation system is used to simulate the thermal environment of the flight process consistent with the aerodynamic thermal data, and to heat the thermal protection material to be tested;

[0025] The detection system is used to detect the thermal physical property parameters of the thermal protection material to be tested under the thermal environment, and transmit the thermal physical property parameter detection results to the control system.

[0026] Furthermore, the preset flight condition parameters include one or more parameters of flight altitude, atmospheric pressure, atmospheric humidity, atmospheric density and aircraft speed; the aerodynamic thermal data include one or more aerodynamic thermal data of cold wall heat flux, wall temperature, pressure distribution, velocity distribution and temperature distribution; the thermal physical property parameters include one or more parameters of emissivity, specific heat capacity, thermal diffusion coefficient, thermal conductivity, thermal resistance and candle burnout.

[0027] Furthermore, simulating the thermal environment of the flight process according to the aerodynamic thermal data includes: calculating the relationship between the change of the heat flux and the wall temperature over time during the flight according to the cold wall heat flux and the wall temperature, and simulating the thermal environment of the flight process according to the relationship between the change of the heat flux and the wall temperature over time.

[0028] Furthermore, the control system includes a host computer, a slave computer and a data acquisition module;

[0029] The host computer is used to determine the preset parameters of the flight condition, and determine the aerodynamic thermal data according to the preset parameters of the flight condition;

[0030] The lower computer is used to control the thermal environment simulation system and the detection system;

[0031] The data acquisition module is used to receive information transmitted by the thermal environment simulation system and the detection system, and transmit the information to the host computer;

[0032] The thermal environment simulation system includes a heater, a sensor and a heat flow meter; the heater is used to heat the thermal protection material to be tested, and a test position is provided on the heater, and the test position is used to place the thermal protection material to be tested; the sensor is used to detect the temperature of the thermal protection material to be tested, and transmit the detection result to the control system; the heat flow meter is used to detect the heat flow of the thermal protection material to be tested, and transmit the detection result to the control system.

[0033] The method of simulating the thermal environment of the flight process according to the relationship between the heat flux and the wall temperature over time includes: a control system controls the heating and cooling operations of the heater according to the heat flux and the wall temperature to simulate the thermal environment of the flight process in real time.

[0034] Furthermore, the detection system includes a differential scanning calorimeter, a flash thermal conductivity meter and a Fourier transform infrared spectrometer; the differential scanning calorimeter is used to detect the specific heat capacity of the thermal protection material to be tested; the flash thermal conductivity meter is used to detect the thermal diffusion coefficient of the thermal protection material; and the Fourier transform infrared spectrometer is used to detect the emissivity of the thermal protection material.

[0035] Furthermore, the emissivity detection and calculation method includes the following steps: using a black body radiation source as a standard radiation source, detecting the radiation output of the black body radiation source; detecting the radiation output of the thermal protection material to be tested; the ratio of the radiation output of the thermal protection material to be tested to the radiation output of the black body radiation source is the emissivity of the thermal protection material to be tested; the specific calculation formula is as follows:

[0036]

[0037] Where ε(T) represents the emissivity of the thermal protection material to be tested, E λ (T) is the radiant emission of the thermal protection material to be tested; E bλ (T) is the radiant output of the black body radiation source.

[0038] Furthermore, the thermal environment simulation system includes a heater, a sensor and a heat flow meter; the heater is used to heat the thermal protection material to be tested, and a test position is provided on the heater, and the test position is used to place the thermal protection material to be tested; the sensor is used to detect the temperature of the thermal protection material to be tested, and transmit the detection result to the control system; the heat flow meter is used to detect the heat flow of the thermal protection material to be tested, and transmit the detection result to the control system;

[0039] The sensors include a front surface temperature sensor, a back surface temperature sensor, a layered temperature sensor and a distance measuring sensor; the thermal protection material to be tested includes a front surface, a back surface and a plurality of layers between the front surface and the back surface, the front surface is a side close to the heater, and the back surface is a side away from the heater; the front surface temperature sensor is used to measure the temperature of the front surface; the back surface temperature sensor is used to measure the temperature of the back surface; the layered temperature sensor is used to measure the temperature of each layer of the thermal protection material to be tested; the distance measuring sensor is used to measure the thickness of the thermal protection material to be tested to obtain the ablation amount.

[0040] Furthermore, the detection and calculation method of the thermal diffusion coefficient is as follows: the time t when the temperature of the back side of the thermal protection material to be tested rises to a preset temperature is detected, and the thermal diffusion coefficient is calculated. The specific formula is as follows:

[0041] α(t)=0.13879*δ 2 / t 1 / 2 (t)

[0042] Wherein, α(t) is the thermal diffusion coefficient of the thermal protection material to be tested, δ is the material thickness of the thermal protection material to be tested, and t 1 / 2 is half of the time t.

[0043] Furthermore, the detection and calculation method of the specific heat capacity is as follows: detecting the heat flow when the test position is vacant as a reference heat flow; detecting the heat flow of the thermal protection material to be tested; detecting the heat flow of the reference object, and calculating the specific heat capacity of the thermal protection material to be tested. The specific formula is as follows:

[0044]

[0045] Among them, q c (t) is the heat flow of the thermal protection material to be tested after correction relative to the reference heat flow, C pcis the specific heat capacity of the thermal protection material to be tested, m c is the mass of the thermal protection material to be tested, is the rate of change of temperature with time;

[0046]

[0047] Among them, q r (t) is the heat flow of the reference object after correction relative to the reference heat flow, C pr is the specific heat capacity of the reference substance, m r The mass of the reference object;

[0048] According to formula (1) and formula (2), the specific heat capacity calculation formula of the thermal protection material to be tested is obtained:

[0049]

[0050] Furthermore, the calculation formula of the thermal conductivity is as follows:

[0051] λ(t)=C pc (t)×ρ×α(t)

[0052] Wherein, λ(t) is the thermal conductivity of the thermal protection material to be tested, and ρ is the density of the thermal protection material to be tested;

[0053] The calculation formula of the thermal resistance is as follows:

[0054]

[0055] Wherein, R is the thermal resistance of the thermal protection material to be tested, T is the temperature, P is the heat transfer power inside the thermal protection material to be tested, and i is the number of layers of the thermal protection material to be tested.

[0056] The above technical solution has the following beneficial effects: When testing the thermal protection material to be tested, the integrated test system for the performance of thermal protection materials of the embodiment of the present invention takes into account the flight conditions and the thermal environment that changes during the flight process. It simulates the actual flight process to test the thermal protection material to be tested, so that the test results are closer to the actual results. At the same time, it can simultaneously perform integrated tests on multiple thermal physical parameters of the thermal protection material to be tested, taking into account the influence between the various parameters, and couples the parameter tests to make the test results more accurate. The integrated test also greatly improves the test efficiency, reduces the number of times the test piece is placed, and avoids the defect of measurement errors that are easy to occur between multiple tests. Its testing method is simple, efficient, and accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0058] Figure 1 is a schematic structural diagram of a thermal protection material performance integrated testing system according to an embodiment of the present invention;

[0059] Figure 2 1 is a schematic flow chart of a method for integrated testing of thermal protection material performance according to an embodiment of the present invention;

[0060] Figure 3 is a graph showing the change of heat flow over time in an embodiment of the present invention;

[0061] Figure 4 is a graph showing the change of surface temperature of different materials over time in an embodiment of the present invention;

[0062] Figure 5 It is a schematic diagram of the process of thermal protection design according to an embodiment of the present invention.

[0063] The meanings of the symbols in the figure are as follows:

[0064] 10. Control system; 20. Thermal environment simulation system; 30. Detection system; 40. Thermal protection material;

[0065] 11. Lower computer; 12. Upper computer; 13. Data acquisition module; 21. Cooling system; 22. Reflector; 23. Heater; 24. Heat flow meter; 31. Differential scanning calorimeter; 32. Flash thermal conductivity meter; 33. Fourier transform infrared spectrometer; 331. Michelson interferometer; 332. Laser collimator. DETAILED DESCRIPTION

[0066] The features and exemplary embodiments of various aspects of the present invention will be described in detail below. In the detailed description below, many specific details are proposed in order to provide a comprehensive understanding of the present invention. However, it is obvious to those skilled in the art that the present invention can be implemented without some of these specific details. The following description of the embodiments is only to provide a better understanding of the present invention by illustrating examples of the present invention. In the drawings and the following description, at least part of the known structures and technologies are not shown in order to avoid unnecessary ambiguity of the present invention; and, for clarity, the size of some structures may be exaggerated. In addition, the features, structures or characteristics described below may be combined in one or more embodiments in any suitable manner.

[0067] like Figure 1 As shown, the integrated test system for thermal protection material performance of an embodiment of the present invention is used to detect the performance of aircraft thermal protection materials, and includes a control system 10, a thermal environment simulation system 20 and a detection system 30. The control system 10 is communicated with the thermal environment simulation system 20 and the detection system 30 respectively.

[0068] The control system 10 is used to determine the preset parameters of the flight condition, determine the aerodynamic thermal data according to the preset parameters of the flight condition, and control the thermal environment simulation system 20 according to the aerodynamic thermal data. The control system 10 includes a host computer 12, a slave computer 11 and a data acquisition module 13.

[0069] The above-mentioned thermal physical parameters include emissivity, specific heat capacity, thermal diffusivity, thermal conductivity, thermal resistance and burnout.

[0070] Emissivity refers to the ratio of the radiant flux radiated per unit area on the surface of an object to the radiant flux radiated by a black body at the same temperature.

[0071] Specific heat capacity refers to the heat capacity of an object per unit mass, that is, the amount of heat absorbed or released when an object per unit mass changes unit temperature.

[0072] Thermal diffusivity is a measure of the rate at which a temperature disturbance at one point in an object is transferred to another point.

[0073] Thermal conductivity refers to the amount of heat transferred through a unit horizontal cross-sectional area per unit time when the vertical downward temperature gradient is 1°C / m.

[0074] Thermal resistance refers to the ratio between the temperature difference at both ends of an object and the power of the heat source when heat is transferred through the object.

[0075] The host computer 12 is used to determine the preset parameters of the flight condition and determine the aerodynamic thermal data according to the preset parameters of the flight condition. The host computer 12 can be a computer device or a remote control terminal or other equipment.

[0076] The lower computer 11 is used to control the thermal environment simulation system 20 and the detection system 30. The lower computer 11 can be a single chip microcomputer, a PLC controller, etc.

[0077] The data acquisition module 13 is used to receive information transmitted by the thermal environment simulation system 20 and the detection system 30 , and transmit the information to the host computer 12 .

[0078] The thermal environment simulation system 20 is used to simulate the thermal environment of the flight process consistent with the aerodynamic thermal data, and to heat the thermal protection material 40 to be tested.

[0079] The thermal environment simulation system 20 includes a heater 23, a sensor (not shown) and a heat flow meter 24. The heater 23 is used to heat the thermal protection material 40 to be tested, and a test position is provided on the heater 23, and the test position is used to place the thermal protection material 40 to be tested; the sensor is used to detect the temperature of the thermal protection material 40 to be tested, and transmit the detection result to the control system 10; the heat flow meter 24 is used to detect the heat flow of the thermal protection material 40 to be tested, and transmit the detection result to the data acquisition module 13.

[0080] The heater 23 in this embodiment is a quartz lamp array heater, and the quartz lamps are arranged in an array, which is conducive to making the heat radiation more uniform. The thermal environment simulation system 20 can also include a cooling system 21 and a reflector 22. The heat flux meter 24 is arranged on the heater 23 below the test position.

[0081] The sensors include a front temperature sensor, a back temperature sensor, a layered temperature sensor and a ranging sensor; the thermal protection material 40 to be tested includes a front side, a back side and a plurality of layers (not shown) located between the front side and the back side, the front side is the side close to the heater 23, and the back side is the side away from the heater 23; the front temperature sensor is used to measure the temperature of the front side; the back temperature sensor is used to measure the temperature of the back side; the layered temperature sensor is used to measure the temperature of each layer of the thermal protection material 40 to be tested; the ranging sensor is used to measure the thickness of the thermal protection material 40 to be tested to obtain the ablation amount.

[0082] The heat protection material 40 is generally a multilayer structure composed of three different materials, and the number of layers is about 15. The layered temperature sensor is respectively arranged on each layer of the heat protection material 40 to detect the temperature of each layer. The ablation amount can be obtained by detecting the thickness change of the heat protection material 40 through the distance measuring sensor.

[0083] The detection system 30 is used to detect the thermal physical parameters of the thermal protection material 40 to be tested in a thermal environment, and transmit the thermal physical parameter detection results to the data acquisition module 13. The detection system 30 includes a differential scanning calorimeter 31, a flash thermal conductivity meter 32 and a Fourier infrared spectrometer 33; the differential scanning calorimeter 31 is used to detect the specific heat capacity of the thermal protection material 40 to be tested; the flash thermal conductivity meter 32 is used to detect the thermal diffusion coefficient of the thermal protection material 40; the Fourier infrared spectrometer 33 is used to detect the emissivity of the thermal protection material 40. The Fourier infrared spectrometer 33 in this embodiment includes a Michelson interferometer 331 and a laser collimator 332.

[0084] like Figure 2 As shown, another embodiment of the present invention provides a thermal protection material performance integrated testing method, which is used in the above-mentioned thermal protection material performance integrated testing system, comprising the following steps:

[0085] S1. Determine the preset parameters of the flight condition.

[0086] The preset parameters of the flight conditions include flight altitude, atmospheric pressure, atmospheric humidity, atmospheric density and aircraft speed.

[0087] S2. Determine aerodynamic thermal data according to preset parameters of flight conditions.

[0088] Aerothermal data include cold wall heat flux, wall temperature, pressure distribution, velocity distribution and temperature distribution.

[0089] S3. The thermal environment of the flight process is simulated according to the aerodynamic thermal data, and the thermal protection material 40 to be tested is heated. At the same time, the thermal physical property parameters of the thermal protection material 40 to be tested are tested through the thermal protection material performance integrated test system to obtain the thermal physical property parameter test results.

[0090] The relationship between the heat flux and the wall temperature during flight is calculated based on the cold wall heat flux and the wall temperature. The thermal environment of the flight process is simulated based on the relationship between the heat flux and the wall temperature, and the thermal protection material 40 to be tested is heated.

[0091] The thermal physical property parameter test is performed on the thermal protection material 40 to be tested under the simulated thermal environment conditions to obtain the thermal physical property parameter test results.

[0092] The detection and calculation method of the emissivity includes the following steps: using a black body radiation source as a standard radiation source, detecting the radiation output of the black body radiation source; detecting the radiation output of the thermal protection material 40 to be tested; the ratio of the radiation output of the thermal protection material 40 to be tested to the radiation output of the black body radiation source is the emissivity of the thermal protection material 40 to be tested; the specific calculation formula is as follows:

[0093]

[0094] Where ε(T) represents the emissivity of the thermal protection material to be tested, E λ (T) is the radiant emission of the thermal protection material to be tested; E bλ (T) is the radiant output of the black body radiation source.

[0095] The detection and calculation method of the thermal diffusion coefficient is as follows: the time t when the temperature of the back side of the thermal protection material 40 to be tested rises to a preset temperature is detected, and the thermal diffusion coefficient is calculated. The specific formula is as follows:

[0096] α(t)=0.13879*δ 2 / t 1 / 2 (t)

[0097] Among them, α(t) is the thermal diffusion coefficient of the thermal protection material to be tested, δ is the material thickness of the thermal protection material to be tested, and t 1 / 2is half of the time t.

[0098] The detection and calculation method of specific heat capacity is as follows: detect the heat flow when the test position is vacant as the reference heat flow; detect the heat flow of the heat protection material 40 to be tested; detect the heat flow of the reference object, and calculate the specific heat capacity of the heat protection material 40 to be tested. The specific formula is as follows:

[0099]

[0100] Among them, q c (t) is the heat flow of the thermal protection material to be tested after correction relative to the reference heat flow, C pc is the specific heat capacity of the thermal protection material to be tested, m c is the mass of the thermal protection material to be tested, is the rate of change of temperature with time;

[0101]

[0102] Among them, q r (t) is the heat flow of the reference object after correction relative to the reference heat flow, C pr is the specific heat capacity of the reference substance, m r The mass of the reference object;

[0103] According to formula (1) and formula (2), the calculation formula of the specific heat capacity of the thermal protection material 40 to be tested is obtained:

[0104]

[0105] The calculation formula of thermal conductivity is as follows:

[0106] λ(t)=C pc (t)×ρ×α(t)

[0107] Wherein, λ(t) is the thermal conductivity of the thermal protection material to be tested, and ρ is the density of the thermal protection material to be tested;

[0108] The thermal resistance is calculated as follows:

[0109]

[0110] Wherein, R is the thermal resistance of the thermal protection material to be tested, T is the temperature, P is the heat transfer power inside the thermal protection material to be tested, and i is the number of layers of the thermal protection material to be tested;

[0111] P(t)=λ(T i+1 (t)-T i (t)).

[0112] like Figure 5 As shown, specifically, the thermal protection design includes a test preparation stage, a test debugging stage and a DUT test stage.

[0113] In the test preparation stage, the MATLAB2017B platform can be used to write the aircraft aerodynamic heat and thermal protection design calculation program. The preset parameters of the flight conditions are used as input conditions to set the safe temperature range of the aircraft's internal structure.

[0114] The aerodynamic thermal data is determined according to preset parameters of the flight condition, and specifically, the aerodynamic thermal data is calculated according to the flight trajectory parameters.

[0115] The test plan is designed simultaneously, the test materials and bracket insulation plan are designed and processed, and the test piece is installed at the test position.

[0116] During the test debugging stage, the heat flux density and temperature of the test piece are measured and checked. If the test requirements are met, the heat flux density and temperature of the test piece are measured; if not, the test parameters are adjusted until the test requirements are met.

[0117] In the test phase of the test piece, the test piece is subjected to a thermal property test to obtain the thermal property parameters: thermal resistance, emissivity, thermal diffusion coefficient, specific heat capacity, thermal conductivity and temperature ablation resistance, and a database is established. In this embodiment, the aerodynamic heat flux is calculated according to the aerodynamic thermal environment of the hypersonic aircraft, and the cold wall heat flux q and the wall temperature T in the calculated aerodynamic thermal data are converted into the thermal conductivity of the wall surface. δ As the input condition for thermal protection structure design and material thermal property test. In this embodiment, the test of thermal protection material performance is a non-steady test, that is, considering the change relationship of heat flow over time during the flight of the aircraft, based on this change relationship, the thermal environment during the flight of the aircraft is simulated to obtain more accurate and reliable test results. Figure 3 As shown, it is the curve of heat flux variation over time of the first-level bottom heat protection plate and the first-level bottom heat protection skirt of this embodiment.

[0118] The thermal environment during the flight process is simulated to heat up and cool down the thermal protection material 40 to be tested, and various thermal physical parameters of the thermal protection material 40 to be tested are tested within a certain flight time to obtain the thermal physical parameter test results.

[0119] The detection and calculation method of the emissivity is as follows: first, the optical path is aligned and adjusted by the laser collimator 332, and then the radiation output at the temperature T is measured by the black body standard radiation source, and then the radiation output of the thermal protection material 40 to be tested is measured at the temperature T. The ratio of the radiation output of the thermal protection material 40 to be tested and the radiation output of the black body standard radiation source is the emissivity of the thermal protection material 40 to be tested. The radiation output curve of the black body standard radiation source can be obtained by measuring the radiation output of the black body standard radiation source at multiple time points, and the radiation output curve of the thermal protection material 40 to be tested can be obtained by measuring the radiation output of the thermal protection material 40 to be tested at multiple time points. Similarly, the emissivity curve of the thermal protection material 40 to be tested can also be obtained. Making a curve graph is conducive to more intuitive observation of the test results. Since the present embodiment uses a quartz lamp array heater as a radiation heat source, the radiation output of the thermal protection material 40 to be tested and the black body standard radiation source can be measured at the same time, which can avoid human errors and greatly improve the test efficiency, accuracy and reliability of the test.

[0120]

[0121] Where ε(T) represents the emissivity of the thermal protection material to be tested, E λ (T) is the radiant emission of the thermal protection material to be tested; E bλ (T) is the radiant output of the black body radiation source.

[0122] Detection and calculation method of thermal diffusion coefficient: First, after placing the thermal protection material 40 to be tested in the test position, the thermal protection material 40 to be tested should be well insulated and heat-insulated around it, so that the heat source radiates vertically to the surface of the product and remains stable. Use a sensor or thermocouple to test the temperature of the back of the thermal protection material 40 to be tested, obtain the temperature rise curve and temperature rise time t, and calculate the thermal diffusion coefficient of the thermal protection material 40 to be tested under one-dimensional heat flow.

[0123] α(t)=0.13879*δ 2 / t 1 / 2 (t)

[0124] Among them, α(t) is the thermal diffusion coefficient of the thermal protection material to be tested, δ is the material thickness of the thermal protection material to be tested, and t 1 / 2 is half of the time t.

[0125] Detection and calculation method of specific heat capacity: detect the heat flow when the test position is vacant as the reference heat flow; set the same heating rate to detect the heat flow of the thermal protection material 40 to be tested; set the same heating rate to detect the heat flow of the reference object sapphire. Perform detection at multiple different time points to obtain the reference heat flow curve, the heat flow curve of the thermal protection material to be tested, and the heat flow curve of the sapphire. Correct the heat flow curve of the thermal protection material to be tested and the heat flow curve of the sapphire relative to the reference heat flow curve to obtain the heat flow correction value h of the thermal protection material to be tested and the heat flow correction value H of the sapphire.

[0126]

[0127] Among them, q c (t) is the heat flow of the thermal protection material to be tested after correction relative to the reference heat flow, C pc is the specific heat capacity of the thermal protection material to be tested, m c is the mass of the thermal protection material to be tested, is the rate of change of temperature with time;

[0128]

[0129] Among them, q r (t) is the heat flow of the reference object after correction relative to the reference heat flow, C pr is the specific heat capacity of the reference substance, m r is the mass of the reference object;

[0130] According to formula (1) and formula (2), the calculation formula of the specific heat capacity of the thermal protection material 40 to be tested is obtained:

[0131]

[0132] Calculation of thermal conductivity: According to the above test results, we get

[0133] λ(t)=C pc (t)×ρ×α(t)

[0134] Wherein, λ(t) is the thermal conductivity of the thermal protection material to be tested, and ρ is the density of the thermal protection material to be tested.

[0135] Calculation of thermal resistance: According to the above test results, the heat transfer power inside the thermal protection material 40 to be tested is as follows:

[0136] P(t)=λ(T i+1 (t)-T i (t));

[0137] The thermal resistance is calculated as follows:

[0138]

[0139] Wherein, R is the thermal resistance of the thermal protection material to be tested, T is the temperature, P is the heat transfer power inside the thermal protection material to be tested, and i is the number of layers of the thermal protection material to be tested (i.e., the layer number).

[0140] Testing and calculation methods of thermal ablation resistance: During the test, the length and width of the test piece are usually increased under the premise that the test equipment allows, and the periphery and non-heating surface of the test piece are insulated to make the test heat transfer path as close to one-dimensional heat transfer as possible. At the same time, during the test, a high-speed camera can be used to record the ablation process to facilitate viewing the test results.

[0141] Finally, the thermal protection design is carried out, and the test results of the thermal physical parameters of the thermal protection material 40 to be tested are input into the computer, and the simulated internal temperature of the aircraft is calculated by the computer. If the calculated temperature is within the safe temperature range of the internal structure of the aircraft, the thermal protection material to be tested meets the design requirements, otherwise it does not meet the design requirements and needs to be replaced with other thermal protection materials. Figure 4 As shown, there are respectively a curve of the change of the outer surface temperature of the quartz cloth with time, a curve of the change of the inner surface temperature of the quartz cloth with time, a curve of the change of the inner surface temperature of the cork with time, and a curve of the change of the inner surface temperature of the fiberglass with time.

[0142] The integrated test method for the performance of thermal protection materials of the present invention couples the thermal physical property parameters. Since the input heat flux of the present invention changes with time, the temperature of the thermal protection material also changes, so that the emissivity, thermal diffusion coefficient, specific heat capacity, thermal conductivity, thermal resistance and temperature-resistant ablation performance of the thermal protection material change with temperature are taken into account, making the test process closer to the real physical process and making the test results more accurate. The integrated test system for the performance of thermal protection materials of the present invention adopts an integrated system, which can conveniently, quickly and rapidly measure a variety of thermal physical properties of thermal protection materials, avoid multiple repetitive work, and greatly save manpower, material and financial costs. The integrated test system for the performance of thermal protection materials of the present invention can reserve interfaces for rapid access to other test systems.

[0143] In the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "upper, lower, inner and outer" are based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first, second or third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0144] In the present invention, unless otherwise clearly specified and limited, the terms "install, connect, connect" should be understood in a broad sense, for example: it can be a fixed connection, a detachable connection or an integral connection; it can also be a mechanical connection, an electrical connection or a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0145] Although the present invention has been described with reference to preferred embodiments, various modifications may be made thereto and parts thereof may be replaced by equivalents without departing from the scope of the present invention. In particular, the various technical features mentioned in the various embodiments may be combined in any manner as long as there are no structural conflicts. The present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A thermal protection material performance integrated testing system, used to detect the performance of aircraft thermal protection materials, characterized in that: It comprises a control system (10), a thermal environment simulation system (20) and a detection system (30), wherein the control system (10) is communicatively connected to the thermal environment simulation system (20) and the detection system (30) respectively; The control system (10) is used to determine flight condition preset parameters, determine aerodynamic thermal data according to the flight condition preset parameters, and control the thermal environment simulation system (20) according to the aerodynamic thermal data; The thermal environment simulation system (20) is used to simulate the thermal environment of a flight process consistent with the aerodynamic thermal data, and to heat the thermal protection material (40) to be tested; The detection system (30) is used to detect the thermal physical property parameters of the thermal protection material (40) to be tested under the thermal environment, and transmit the thermal physical property parameter detection results to the control system (10); The preset flight condition parameters include flight altitude, atmospheric pressure, atmospheric humidity, atmospheric density and aircraft speed; the aerodynamic thermal data include cold wall heat flux, wall temperature, pressure distribution, velocity distribution and temperature distribution; the thermal physical property parameters include emissivity, specific heat capacity, thermal diffusion coefficient, thermal conductivity, thermal resistance and ablation amount; The control system (10) comprises a host computer (12), a slave computer (11) and a data acquisition module (13); The host computer (12) is used to determine the preset parameters of the flight condition, and determine the aerodynamic heat data according to the preset parameters of the flight condition; The lower computer (11) is used to control the thermal environment simulation system (20) and the detection system (30); The data acquisition module (13) is used to receive information transmitted by the thermal environment simulation system (20) and the detection system (30), and transmit the information to the host computer (12); The detection system (30) comprises a differential scanning calorimeter (31), a flash thermal conductivity meter (32) and a Fourier transform infrared spectrometer (33); the differential scanning calorimeter (31) is used to detect the specific heat capacity of the thermal protection material (40) to be tested; The flash thermal conductivity meter (32) is used to detect the thermal diffusion coefficient of the thermal protection material (40); the Fourier transform infrared spectrometer (33) is used to detect the emissivity of the thermal protection material (40); the Fourier transform infrared spectrometer (33) includes a Michelson interferometer (331) and a laser collimator (332).

2. The thermal protection material performance integrated testing system according to claim 1, characterized in that: The thermal environment simulation system (20) comprises a heater (23), a sensor and a heat flow meter (24); the heater (23) is used to heat the thermal protection material (40) to be tested, and a test position is provided on the heater (23), and the test position is used to place the thermal protection material (40) to be tested; the sensor is used to detect the temperature of the thermal protection material (40) to be tested, and transmit the detection result to the control system (10); the heat flow meter (24) is used to detect the heat flow of the thermal protection material (40) to be tested, and transmit the detection result to the control system (10).

3. The thermal protection material performance integrated testing system according to claim 2, characterized in that: The sensor comprises a front surface temperature sensor, a back surface temperature sensor, a layered temperature sensor and a distance measuring sensor; the thermal protection material (40) to be measured comprises a front surface, a back surface and a plurality of layers located between the front surface and the back surface, the front surface is a side close to the heater (23), and the back surface is a side away from the heater (23); the front surface temperature sensor is used to measure the temperature of the front surface; the back surface temperature sensor is used to measure the temperature of the back surface; the layered temperature sensor is used to measure the temperature of each layer of the thermal protection material (40) to be measured; and the distance measuring sensor is used to measure the thickness of the thermal protection material (40) to be measured to obtain the ablation amount.

4. A thermal protection material performance integrated testing method, the method using a thermal protection material performance integrated testing system, characterized in that: The following steps are involved: Determine the preset parameters of flight conditions; Determining aerodynamic thermal data according to preset parameters of the flight condition; Simulating the thermal environment of the flight process according to the aerodynamic thermal data, heating the thermal protection material (40) to be tested, and simultaneously testing the thermal physical property parameters of the thermal protection material (40) to be tested by the thermal protection material performance integrated testing system to obtain thermal physical property parameter testing results; The thermal protection material performance integrated testing system comprises a control system (10), a thermal environment simulation system (20) and a detection system (30), wherein the control system (10) is respectively communicatively connected to the thermal environment simulation system (20) and the detection system (30); The control system (10) is used to determine flight condition preset parameters, determine aerodynamic thermal data according to the flight condition preset parameters, and control the thermal environment simulation system (20) according to the aerodynamic thermal data; The thermal environment simulation system (20) is used to simulate the thermal environment of a flight process consistent with the aerodynamic thermal data, and to heat the thermal protection material (40) to be tested; The detection system (30) is used to detect the thermal physical property parameters of the thermal protection material (40) to be tested under the thermal environment, and transmit the thermal physical property parameter detection results to the control system (10); The preset flight condition parameters include flight altitude, atmospheric pressure, atmospheric humidity, atmospheric density and aircraft speed; the aerodynamic thermal data include cold wall heat flux, wall temperature, pressure distribution, velocity distribution and temperature distribution; the thermal physical property parameters include emissivity, specific heat capacity, thermal diffusion coefficient, thermal conductivity, thermal resistance and ablation amount; The simulating the thermal environment of the flight process according to the aerodynamic thermal data comprises: calculating the relationship between the change of the heat flux and the wall temperature over time during the flight according to the cold wall heat flux and the wall temperature, and simulating the thermal environment of the flight process according to the relationship between the change of the heat flux and the wall temperature over time; The control system (10) comprises an upper computer (12), a lower computer (11) and a data acquisition module (13); the upper computer (12) is used to determine the preset parameters of the flight condition, and determine the aerodynamic thermal data according to the preset parameters of the flight condition; the lower computer (11) is used to control the thermal environment simulation system (20) and the detection system (30); the data acquisition module (13) is used to receive information transmitted by the thermal environment simulation system (20) and the detection system (30), and transmit the information to the upper computer (12); The detection system (30) comprises a differential scanning calorimeter (31), a flash thermal conductivity meter (32) and a Fourier transform infrared spectrometer (33); the differential scanning calorimeter (31) is used to detect the specific heat capacity of the thermal protection material (40) to be tested; The flash thermal conductivity meter (32) is used to detect the thermal diffusion coefficient of the thermal protection material (40); the Fourier transform infrared spectrometer (33) is used to detect the emissivity of the thermal protection material (40); the Fourier transform infrared spectrometer (33) includes a Michelson interferometer (331) and a laser collimator (332).

5. The integrated testing method for thermal protection material performance according to claim 4, characterized in that: The thermal environment simulation system (20) comprises a heater (23), a sensor and a heat flow meter (24); the heater (23) is used to heat the thermal protection material (40) to be tested, and a test position is provided on the heater (23), and the test position is used to place the thermal protection material (40) to be tested; the sensor is used to detect the temperature of the thermal protection material (40) to be tested, and transmit the detection result to the control system (10); the heat flow meter (24) is used to detect the heat flow of the thermal protection material (40) to be tested, and transmit the detection result to the control system (10); The thermal environment of the flight process is simulated according to the relationship between the change of the heat flux and the change of the wall temperature over time, including: a control system controls the heating and cooling operations of the heater (23) according to the heat flux and the wall temperature, so as to simulate the thermal environment of the flight process in real time.

6. The integrated testing method for thermal protection material performance according to claim 4, characterized in that: The emissivity detection and calculation method comprises the following steps: using a black body radiation source as a standard radiation source, detecting the radiation output of the black body radiation source; detecting the radiation output of the thermal protection material to be tested; the ratio of the radiation output of the thermal protection material to be tested to the radiation output of the black body radiation source is the emissivity of the thermal protection material to be tested; the specific calculation formula is as follows: Where ε(T) represents the emissivity of the thermal protection material to be tested, E λ (T) is the radiant emission of the thermal protection material to be tested; E bλ (T) is the radiant output of the black body radiation source.

7. The integrated testing method for thermal protection material performance according to claim 4, characterized in that: The thermal environment simulation system (20) comprises a heater (23), a sensor and a heat flow meter (24); the heater (23) is used to heat the thermal protection material (40) to be tested, and a test position is provided on the heater (23), and the test position is used to place the thermal protection material (40) to be tested; the sensor is used to detect the temperature of the thermal protection material (40) to be tested, and transmit the detection result to the control system (10); the heat flow meter (24) is used to detect the heat flow of the thermal protection material (40) to be tested, and transmit the detection result to the control system (10); The sensor comprises a front surface temperature sensor, a back surface temperature sensor, a layered temperature sensor and a distance sensor; the thermal protection material (40) to be tested comprises a front surface, a back surface and a plurality of layers located between the front surface and the back surface, the front surface is a side close to the heater (23), and the back surface is a side away from the heater (23); the front surface temperature sensor is used to measure the temperature of the front surface; the back surface temperature sensor is used to measure the temperature of the back surface; the layered temperature sensor is used to measure the temperature of each layer of the thermal protection material (40) to be tested; the distance sensor is used to measure the thickness of the thermal protection material (40) to be tested, so as to obtain the ablation amount; The detection and calculation method of the thermal diffusion coefficient is as follows: detect the time t when the back surface of the thermal protection material to be tested rises to a preset temperature, and calculate the thermal diffusion coefficient. The specific formula is as follows: α(t)=0.13879*δ 2 / t 1 / 2 (t) Wherein, α(t) is the thermal diffusion coefficient of the thermal protection material to be tested, δ is the material thickness of the thermal protection material to be tested, and t 1 / 2 is half of the time t.

8. The integrated testing method for thermal protection material performance according to claim 7, characterized in that: The detection and calculation method of the specific heat capacity is as follows: detect the heat flow when the test position is vacant as the reference heat flow; detect the heat flow of the thermal protection material to be tested; detect the heat flow of the reference object, and calculate the specific heat capacity of the thermal protection material to be tested. The specific formula is as follows: Among them, q c (t) is the heat flow of the thermal protection material to be tested after correction relative to the reference heat flow, C pc is the specific heat capacity of the thermal protection material to be tested, m c is the mass of the thermal protection material to be tested, is the rate of change of temperature with time; Among them, q r (t) is the heat flow of the reference object after correction relative to the reference heat flow, C pr is the specific heat capacity of the reference substance, m r The mass of the reference object; According to formula (1) and formula (2), the specific heat capacity calculation formula of the thermal protection material to be tested is obtained:

9. The integrated test method for thermal protection material performance according to claim 8, characterized in that: The calculation formula of the thermal conductivity is as follows: λ(t)=C pc (t)×ρ×α(t) Wherein, λ(t) is the thermal conductivity of the thermal protection material to be tested, and ρ is the density of the thermal protection material to be tested.

10. The integrated testing method for thermal protection material performance according to claim 4, characterized in that: The calculation formula of the thermal resistance is as follows: Wherein, R is the thermal resistance of the thermal protection material to be tested, T is the temperature, t is the time, P is the heat transfer power inside the thermal protection material to be tested, and i is the number of layers of the thermal protection material to be tested.

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