Arc-heating-based thermo-electric performance simulation and measurement device and method

Abstract

The present invention belongs to the field of aircraft ground aerodynamic heat test research, and relates to an arc-heating-based thermo-electric performance simulation and measurement device and method. The device comprises an arc heater, a mixing chamber, a nozzle, a model assembly, an antenna assembly, a focusing mirror assembly and a processor, wherein an internal cavity of the mixing chamber is in communication with an arc channel of the arc heater; a cold gas medium is received and mixed with a test medium flowing into the arc heater, and incoming flow parameters and the uniformity of the test medium are adjusted; the nozzle is in communication with the internal cavity of the mixing chamber; the test medium, which flows into the mixing chamber, is received and is subjected to expansion and acceleration to generate a supersonic airflow; the model assembly comprises a conduit and models connected to a wall surface of the conduit, the conduit and the models forming a cavity structure; the supersonic airflow, which flows into the nozzle, heats the models; and the processor receives a reflected signal and a transmitted signal, and calculates a transmittance change value and the dielectric constant of the models in a high-temperature state. The test and testing requirements for the high-temperature microwave property and dielectric property of a wave-transparent material under ablation conditions are met.

Description

A device and method for simulating and measuring the thermo-electric properties based on electric arc heating

[0001] This application claims priority to Chinese Patent Application No. 2024119053451, filed on December 23, 2024, entitled "A device and method for simulating and measuring thermo-electric properties based on electric arc heating", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This invention relates to a special test method for simulating ground tests of aircraft, and in particular to a device and method for simulating and measuring thermo-electric properties based on electric arc heating, belonging to the field of research on ground aerodynamic and thermal tests of aircraft. Background Technology

[0003] During high-speed flight, radomes are subjected to intense air compression and friction, causing them to be heated to extremely high temperatures. Under these conditions, the wave-transmitting properties of the radome's materials undergo significant changes. To meet the performance requirements of spacecraft, which fly at low altitudes and high speeds, the high enthalpy, high heat flux, and high dynamic pressure aerodynamic environment causes the windward side of the radome to heat up rapidly, ablate, and even melt or vaporize, with surface temperatures exceeding 2000℃. Therefore, research on the wave-transmitting properties of radomes at high temperatures has always been one of the most important challenges in spacecraft development. Currently, research on high-temperature microwave-transparent materials for radomes, both domestically and internationally, falls into two categories: static heating and dynamic heating. Static heating relies on methods such as quartz lamps, oxyacetylene torches, or solar furnaces. However, this method lacks simulation of the dynamic aerodynamic heating environment of aircraft, failing to accurately reflect the surface state of the aircraft during flight. Furthermore, the surface temperature achievable by this method is limited, making it difficult to exceed 2000℃. The second category utilizes electric arc wind tunnels to simulate the dynamic aerodynamic heating conditions of aircraft reentry, conducting ablation tests and simultaneously studying the dynamic microwave performance of high-temperature radomes. However, previously, limitations in equipment simulation capabilities and the inability to meet anechoic chamber conditions at the wind tunnel site prevented the guarantee of accurate measurement of material microwave transmission performance. Currently, with the improvement of simulation and measurement capabilities, research on the wave transmission performance of materials based on electric arc heating has been carried out. Patent (ZL201920772523.6) provides a method for conducting ablation-wave transmission tests in an electric arc wind tunnel, but it can only provide results for a single frequency point. Patent (CN202310784597.2) provides a high-temperature broadband wave transmission rate test and measurement device for wave-transmitting materials based on electric arc wind tunnel heating. It mainly realizes the simulation of high enthalpy and low dynamic pressure at higher flight altitudes and can achieve the measurement of high-temperature transmittance over a wide frequency range. However, the material surface temperature can only reach about 2000℃, and it cannot achieve online measurement of the high-temperature dielectric constant. In order to meet the requirements of material wave transmission performance research under lower aircraft altitude and high dynamic pressure conditions, and to realize the measurement of wave transmission rate changes and dielectric constant of wave-transmitting materials at high temperatures, further research is needed. Summary of the Invention

[0004] The technical problem solved by this invention is to provide a device and method for simulating and measuring the thermo-electric properties based on electric arc heating. It utilizes a low-ablation electric arc heater to provide the ability to simulate the pure airflow under aerodynamic heating conditions for microwave-transparent materials. At the same time, it uses a microwave measurement system to realize the real-time measurement of the high-temperature microwave transmission performance of microwave-transparent materials under dynamic heating conditions, thus meeting the experimental and testing requirements for the high-temperature microwave performance and dielectric properties of microwave-transparent materials under ablation conditions.

[0005] The technical solution of the present invention is as follows:

[0006] A device for simulating and measuring the thermo-electric properties based on electric arc heating, comprising:

[0007] An electric arc heater, by igniting an arc, breaks down between the anode and cathode of the electric arc heater to establish an electric arc channel, thereby heating the incoming test medium;

[0008] The mixing chamber has an internal cavity connected to the arc channel of the arc heater. It receives cold gas medium from the outside and mixes it with the test medium flowing into the arc heater to adjust the incoming flow parameters and uniformity of the test medium.

[0009] The nozzle is connected to the internal cavity of the mixing chamber, and receives the test medium flowing into the mixing chamber. After expansion and acceleration, it generates a supersonic airflow.

[0010] The model assembly includes a conduit and a model. The wall of the model is connected to the wall of the conduit to form a cavity structure, which is connected to a nozzle. There are two models, located on opposite sides of the cavity structure, and the models are heated by the supersonic airflow flowing in from the nozzle.

[0011] The antenna assembly includes a first antenna and a second antenna. The first antenna receives electromagnetic wave signals output by the processor, radiates plane waves into space, and simultaneously returns reflected signals to the processor. The second antenna receives transmitted plane waves focused by a second focusing lens and sends them to the processor.

[0012] The focusing lens assembly includes a first focusing lens and a second focusing lens. The first focusing lens focuses the plane wave radiated into space by the first antenna and then transmits it to the model. The second focusing lens focuses the transmitted plane wave that has passed through the model.

[0013] The processor receives reflected signals from the first antenna in real time and transmitted plane wave signals from the second antenna in real time, and calculates the transmittance change and dielectric constant of the model under high temperature conditions.

[0014] In the above-mentioned thermo-electric performance simulation and measurement device based on electric arc heating, the mixing chamber includes an air intake rectification device and a main body. The air intake rectification device includes several air intake channels disposed on the outer wall of the main body and communicating with the internal cavity of the main body. The air intake channels are used to introduce cold gas medium to mix with the test medium flowing in from the electric arc heater, thereby adjusting the incoming flow parameters and uniformity of the test medium.

[0015] In the above-mentioned thermo-electric performance simulation and measurement device based on electric arc heating, the main body includes a coaxial inner layer and an outer layer, and a fluid channel is provided between the inner layer and the outer layer. A cooling medium is introduced into the fluid channel to cool the main body.

[0016] In the above-mentioned thermo-electric performance simulation and measurement device based on electric arc heating, the inner layer material is copper and the outer layer material is steel.

[0017] In the above-mentioned thermo-electric performance simulation and measurement device based on electric arc heating, the internal cavity of the nozzle has a variable inner diameter structure, with the small end of the cavity connected to the internal cavity of the mixing chamber and the large end of the cavity connected to the internal cavity of the duct.

[0018] In the above-mentioned thermo-electric performance simulation and measurement device based on electric arc heating, the nozzle is a water-cooled sandwich structure, the inner shell is made of copper, and the outer wall of the inner shell is a thin-walled reinforced structure.

[0019] In the above-mentioned thermo-electric performance simulation and measurement device based on electric arc heating, the cross-section of the internal cavity of the model component is rectangular, the model is a rectangular flat plate structure, and the three sides of the flat plate structure are respectively connected to the side of the bottom of the conduit and the two side walls of the conduit to form a whole, and the two flat plate structures are arranged opposite to each other.

[0020] The above-mentioned thermo-electric performance simulation and measurement device based on electric arc heating also includes a linear track system. The antenna assembly and the focusing lens assembly are coaxially mounted on the linear track system. The first antenna, the second antenna, the first focusing lens, and the second focusing lens can move along the linear track system. The linear track system adopts an electric servo scanning mechanism.

[0021] The above-mentioned thermo-electric performance simulation and measurement device based on electric arc heating also includes a heat insulation frame and a pressure frame. The heat insulation frame and the pressure frame are set at the end of the model. The heat insulation frame insulates the model, and the pressure frame presses and seals it.

[0022] The above-mentioned thermo-electric performance simulation and measurement device based on electric arc heating also includes a first temperature measuring device and a second temperature measuring device, which are used to measure the back temperature of the two models respectively; both the first temperature measuring device and the second temperature measuring device adopt K-type platinum-rhodium thermocouples with a temperature measurement range of 0 to 1300℃.

[0023] In the aforementioned thermo-electric performance simulation and measurement device based on electric arc heating, the model surface temperature is calculated using the following formula based on the temperature of the back side of the model:

[0024] Among them, T s T represents the surface temperature of the model. w ν is the temperature at the back of the model, k is the thermal conductivity, l is the model thickness, and q is the cold wall heat flux.

[0025] In the above-mentioned thermo-electric performance simulation and measurement device based on electric arc heating, the first antenna and the second antenna are horn antennas; the first focusing lens and the second focusing lens are quartz biconvex lenses.

[0026] In the above-mentioned thermo-electric performance simulation and measurement device based on electric arc heating, the electrode of the electric arc heater is a ring electrode. By combining multiple ring electrodes, the current is divided into arcs during operation, and the total current is evenly distributed to a single ring electrode to minimize electrode ablation.

[0027] In the above-mentioned thermo-electric performance simulation and measurement device based on electric arc heating, the signal transmission and acquisition frequency range of the processor is 1 to 50 GHz, and the time acquisition frequency of the 1 to 50 GHz spectrum map is ≥0.1 frames / s.

[0028] In the aforementioned thermo-electric performance simulation and measurement device based on electric arc heating, the processor receives reflected signals from the first antenna in real time and transmitted plane wave signals from the second antenna in real time, calculating the transmittance change and dielectric constant of the model under high-temperature conditions, including: δ=10(S21'—S21") / 10

[0029] Where δ is the transmittance change at high temperature, ε is the dielectric constant, d is the thickness of the plate model, λ0 is the incident wave frequency, S11 is the reflected signal, S21 is the transmitted plane wave signal, S21' is the transmitted plane wave signal at the end of the test, and S21" is the average value of the transmitted plane wave signal within n seconds before the start of the test, where n is 0.5-1s.

[0030] The above-mentioned thermo-electric performance simulation and measurement device based on electric arc heating also includes a transmission cable, through which the processor is connected to the first antenna and the second antenna for signal transmission.

[0031] A method for simulating and measuring the thermo-electric properties based on electric arc heating, characterized in that it is applied to the aforementioned measuring device and includes:

[0032] An arc is ignited in the arc heater, and a breakdown occurs between the anode and cathode of the arc heater to establish an arc channel, which heats the incoming test medium.

[0033] Cold gas medium is introduced into the mixing chamber and mixed with the heated test medium flowing in from the electric arc heater. The inflow parameters and uniformity of the test medium are adjusted. Then the test medium flows into the nozzle and is expanded and accelerated by the nozzle to generate a supersonic airflow.

[0034] The supersonic airflow flows into the model assembly to heat the two models that are set up opposite each other, and then the supersonic airflow is discharged into the atmosphere.

[0035] The processor outputs an electromagnetic wave signal and transmits it to the first antenna. The first antenna radiates the electromagnetic wave signal into space as a plane wave and simultaneously returns a reflected signal to the processor. The plane wave is focused by the first focusing lens and then transmitted through the model. The transmitted plane wave signal is focused by the second focusing lens, received by the second antenna, and then sent to the processor's signal receiving end in real time.

[0036] The processor calculates the transmittance change and dielectric constant of the model under high temperature conditions based on the received reflected signal and the transmitted plane wave signal.

[0037] Compared with the prior art, the present invention has at least the following beneficial effects:

[0038] (1) The thermal-electric performance simulation and measurement device based on electric arc heating provided in this embodiment of the invention includes an electric arc heater, a mixing chamber, a nozzle, a model assembly, an antenna assembly, a focusing lens assembly, and a processor. The internal cavity of the mixing chamber is connected to the electric arc channel of the electric arc heater. The cold gas medium introduced through the supersonic air intake channel is mixed with the test medium flowing into the electric arc heater to improve the penetration speed and penetration depth of the mixture, thereby adjusting the incoming flow parameters and uniformity of the test medium. The nozzle is connected to the internal cavity of the mixing chamber and receives the test medium flowing into the mixing chamber. After expansion and acceleration, it generates a supersonic airflow. The model assembly includes a conduit and a model connected to the conduit wall. The two together form an integrated cavity structure. The two models are located on both sides of the cavity structure. The supersonic airflow flowing into the nozzle heats the model to achieve simulation of a higher thermal environment and a higher surface temperature of the model. The processor receives reflected and transmitted signals from the antenna in real time and calculates the transmittance change value and dielectric constant of the model under high temperature conditions. This invention realizes the experimental and testing requirements of high temperature microwave performance and dielectric performance of transparent materials under ablation conditions through the overall structural module design.

[0039] (2) The real-time example of the present invention provides a thermo-electric performance simulation and measurement device based on electric arc heating, which realizes the measurement of high temperature transmittance and dielectric constant of the wave-transmitting material under electric arc heating ablation, as well as the high temperature simulation measurement of wave-transmitting performance under medium and low enthalpy and large dynamic pressure under low flight altitude and high flight speed conditions; the real-time example of the present invention realizes the ground test simulation and measurement of high temperature wave-transmitting performance under surface temperature conditions of up to 3000℃.

[0040] (3) The real-time example of the present invention provides a thermo-electric performance simulation and measurement device based on electric arc heating. It uses a low-ablation electric arc heater to provide the simulation capability of pure airflow under aerodynamic heating conditions for transparent materials. At the same time, it uses a microwave measurement system to realize the real-time measurement of the high-temperature transparent performance of transparent materials under dynamic heating conditions, thus meeting the experimental and testing requirements for the high-temperature microwave performance and dielectric performance of transparent materials under ablation conditions. Attached Figure Description

[0041] Figure 1 is a cross-sectional view of the thermo-electric performance simulation and measurement device based on electric arc heating in an embodiment of the present invention;

[0042] Figure 2 is a schematic diagram of the connection between the nozzle and the model assembly in an embodiment of the present invention;

[0043] Figure 3 is a cross-sectional view of the mixing chamber in an embodiment of the present invention, wherein Figure 3a is a radial cross-sectional view and Figure 3b is an axial cross-sectional view. Detailed Implementation

[0044] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments:

[0045] As shown in Figure 1, the thermo-electric performance simulation and measurement device based on electric arc heating in this embodiment of the invention includes an electric arc heater 1, a mixing chamber 2, a nozzle 3, a model assembly, an antenna assembly, a focusing lens assembly, a heat insulation frame 6, a pressure frame 7, a first temperature measuring device 8, a second temperature measuring device 9, a transmission cable 14, a processor 15, and a linear track system 16. The model assembly includes a conduit 4 and a model 5, the antenna assembly includes a first antenna 10 and a second antenna 13, and the focusing lens assembly includes a first focusing lens 11 and a second focusing lens 12.

[0046] Arc heater 1 establishes an arc channel by igniting an arc between its anode and cathode to heat the incoming test medium. In this embodiment of the invention, the electrodes of arc heater 1 are annular electrodes. By combining multiple annular electrodes, current arc splitting is used during operation to evenly distribute the total current to a single annular electrode, thereby minimizing electrode erosion.

[0047] As shown in Figure 3, the mixing chamber 2 includes an air intake rectification device 2-1 and a body 2-2. The air intake rectification device 2-1 includes several air intake channels disposed on the outer wall of the body 2-2 and communicating with the internal cavity of the body 2-2. In this embodiment of the invention, there are 8 air intake channels with a diameter of 6 mm, evenly distributed radially at 8×45°. The internal cavity of the body 2-2 is connected to the arc channel of the arc heater 1. The air intake channels are circulated with a cold gas medium (e.g., air or pure nitrogen, at a temperature of 280K~300K) to mix with the heated test medium flowing into the arc heater 1, further adjusting the incoming flow parameters and optimizing their uniformity. The incoming flow parameters include enthalpy, temperature, and pressure. The body 2-2 includes a coaxial inner layer and an outer layer. A fluid channel is provided between the inner and outer layers. Cooling medium is circulated through the fluid channel to cool the body 2-2. The inner layer is made of copper, and the outer layer is made of steel. The two end faces are flush, and the joints are brazed. A water channel is formed between the inner and outer layers, and forced cooling with circulating water is used. As shown in Figure 3a, in this embodiment of the invention, the air intake rectifier 2-1 adopts a supersonic air intake nozzle design to enable the cold medium to enter the mixing chamber at supersonic speed, thereby improving the penetration speed and penetration depth of the air intake and increasing the mixing efficiency and uniformity.

[0048] Figure 2 shows a cross-sectional view along the axial direction of the connection between the nozzle and the model assembly. The nozzle 3 is connected to the internal cavity of the mixing chamber 2. The test medium flowing into the mixing chamber 2 is expanded and accelerated to generate a supersonic airflow. In this embodiment of the invention, the cross-section and longitudinal section of the nozzle 3 are both rectangular. The internal cavity is a variable inner diameter structure. The small end of the cavity is connected to the internal cavity of the mixing chamber 2, and the large end of the cavity is connected to the internal cavity of the conduit 4. The nozzle 3 is a water-cooled sandwich structure. The inner shell is made of pure copper and adopts a thin-walled and reinforced structure. The height from the inlet to the outlet is consistent. The nozzle 3 adopts a profile design from the inlet to the outlet for a smooth transition.

[0049] As shown in Figure 2, the model assembly includes a conduit 4 and a flat plate model 5. The wall of the flat plate model 5 is connected to the wall of the conduit 4 to form a cavity structure. In this embodiment, the cross-section and longitudinal section of the model assembly are both rectangular, matching the shape of the nozzle 3. The transverse and longitudinal sections of the internal cavity are also rectangular. The flat plate model 5 consists of two rectangular flat plate structures. The three sides of the flat plate structure are connected to the bottom side of the conduit 4 and the two side walls of the conduit 4, respectively, so that the conduit 4 and the model 5 form a whole. The two rectangular flat plate structures are located on both sides of the cavity structure and are arranged opposite to each other, becoming part of the wall of the model assembly. The model assembly receives the supersonic airflow flowing in from the nozzle 3 to heat the flat plate model 5. In this embodiment, the flat plate model 5 has a size of 100mm × 100mm. A heat insulation frame 6 and a pressure frame 7 are set at the end of the flat plate model 5. The heat insulation frame 6 insulates the flat plate model 5, and the pressure frame 7 presses and seals it.

[0050] The first antenna 10, focusing lens 11, focusing lens 12, and second antenna 13 are arranged on a linear track system 16 that can be electrically / manually adjusted to ensure coaxiality and enable rapid and accurate adjustment of the distance between the four components, as well as calibration operations. In this embodiment of the invention, the linear track system 16 adopts an electric servo scanning mechanism with a scanning distance of 0-1000mm and a scanning accuracy of ≤10μm.

[0051] The first antenna 10 and the second antenna 13 are horn antennas, and the first focusing lens 11 and the second focusing lens 12 are quartz biconvex lenses. The antennas and focusing lenses are arranged separately and independently.

[0052] The first temperature measuring device 8 and the first temperature measuring device 9 are used to measure the back surface temperature of the two plate models 5, respectively. Both use K-type platinum-rhodium thermocouples with a temperature range of 0–1300℃. The back surface temperature T of the plate model 5 measured by the first temperature measuring device 8 and the first temperature measuring device 9 is... w Based on one-dimensional thermal conductivity, the surface temperature T of the reverse mold plate model 5 is calculated. s :

[0053] Among them, T s T represents the surface temperature of the model. w ν is the temperature at the back of the model, k is the thermal conductivity, l is the model thickness, and q is the cold wall heat flux.

[0054] The processor 15 uses a vector network analyzer, which can realize the output and continuous acquisition of wide-band microwave signals. The signal transmission and acquisition frequency range is 1 to 50 GHz, and the time acquisition frequency of the 1 to 50 GHz spectrum map is ≥0.1 frames / s.

[0055] Processor 15 receives reflected signals from first antenna 10 in real time and transmitted plane wave signals from second antenna 13 in real time. It calculates the transmittance change and dielectric constant of Model 5 under high temperature conditions (e.g., 1000–3000℃), including: δ = 10(S21'—S21") / 10

[0056] Wherein, δ is the transmittance change at high temperature, ε is the dielectric constant, d is the thickness of the plate model, λ0 is the incident wave frequency, S11 is the reflected signal, S21 is the transmitted plane wave signal, S21' is the transmitted plane wave signal at the end of the test, and S21" is the average value of the transmitted plane wave signal within n seconds before the start of the test, where n is 0.5-1s. In this embodiment of the invention, n is 1 second.

[0057] The processor 15 is connected to the first antenna 10 and the second antenna 13 via a transmission cable 14 for signal transmission.

[0058] The present invention also provides a method for simulating and measuring the thermo-electric properties based on electric arc heating, applied to the above-mentioned measuring device, comprising the following steps:

[0059] 1. The arc heater 1 establishes an arc channel by igniting an arc between the anode and cathode of the arc heater 1, thereby heating the incoming test medium.

[0060] 2. Cold gas medium from the outside is introduced into the mixing chamber 2 through the airflow channel and mixed with the heated test medium flowing in from the electric arc heater 1. The incoming flow parameters and uniformity of the test medium are adjusted, and then it flows into the nozzle 3. After being expanded and accelerated by the nozzle 3, it generates a supersonic airflow.

[0061] 3. The supersonic airflow flows into the model assembly and heats the two relatively set flat plate models 5. Then the supersonic airflow is directly discharged into the atmosphere.

[0062] 4. The signal output terminal of the vector network analyzer 15 outputs an electromagnetic wave signal within a certain frequency band through the transmission cable 14 and transmits it to the first antenna 10. The first antenna 10 radiates the above-mentioned frequency band signal into space as a plane wave, and at the same time returns a reflected signal S11 to the vector network analyzer 15. After being focused by the first focusing lens 11, the plane wave is transmitted through the flat plate model 5. The transmitted plane wave is then focused by the second focusing lens 12, received by the second antenna 13, and transmitted back to the signal input terminal of the vector network analyzer 15 through the transmission cable 14 and is collected in real time, i.e., the transmitted signal S21.

[0063] 5. The vector network analyzer 15 calculates the transmittance change δ and dielectric constant ε of the plate model 5 under high temperature conditions based on the received reflected signal S11 and the transmitted plane wave signal S21.

[0064] The above description is only the best specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the protection scope of the present invention.

[0065] The contents not described in detail in this specification are common knowledge to those skilled in the art.

Claims

1. A device for simulating and measuring the thermo-electric properties based on electric arc heating, characterized in that, include: The electric arc heater (1) establishes an electric arc channel by breaking down between the anode and cathode of the electric arc heater (1) through arc ignition, thereby heating the incoming test medium; The mixing chamber (2) has an internal cavity connected to the arc channel of the arc heater (1), receives the cold gas medium introduced from the outside, mixes it with the test medium flowing into the arc heater (1), and adjusts the incoming flow parameters and uniformity of the test medium. The nozzle (3) is connected to the internal cavity of the mixing chamber (2) and receives the test medium flowing into the mixing chamber (2) and generates a supersonic airflow after expansion and acceleration. The model assembly includes a conduit (4) and a model (5). The wall of the model (5) is connected to the wall of the conduit (4) to form a cavity structure. The cavity structure is connected to the nozzle (3). There are two models (5), which are located on both sides of the cavity structure. The supersonic airflow flowing in from the nozzle (3) heats the model (5). The antenna assembly includes a first antenna (10) and a second antenna (13). The first antenna (10) receives the electromagnetic wave signal output by the processor (15) and radiates a plane wave into space, while simultaneously returning a reflected signal to the processor (15). The second antenna (13) receives the transmitted plane wave focused by the second focusing lens (12) and sends it to the processor (15). The focusing lens assembly includes a first focusing lens (11) and a second focusing lens (12). The first focusing lens (11) focuses the plane wave radiated by the first antenna (10) into space and transmits it to the model (5). The second focusing lens (12) focuses the transmitted plane wave that has passed through the model (5). The processor (15) receives the reflected signal from the first antenna (10) in real time and the transmitted plane wave signal from the second antenna (13) in real time, and calculates the transmittance change and dielectric constant of the model (5) under high temperature conditions.

2. The device for simulating and measuring the thermo-electric properties based on electric arc heating according to claim 1, characterized in that, The mixing chamber (2) includes an air intake rectifier (2-1) and a body (2-2). The air intake rectifier (2-1) includes several air intake channels disposed on the outer wall of the body (2-2) and connected to the internal cavity of the body (2-2). The air intake channels are used to introduce cold gas medium to mix with the test medium flowing in from the electric arc heater (1) to adjust the incoming flow parameters and uniformity of the test medium.

3. The device for simulating and measuring the thermo-electric properties based on electric arc heating according to claim 2, characterized in that, The body (2-2) includes a coaxial inner layer and an outer layer, and a fluid channel is provided between the inner layer and the outer layer. A cooling medium is introduced through the fluid channel to cool the body (2-2).

4. The device for simulating and measuring the thermo-electric properties based on electric arc heating according to claim 3, characterized in that, The inner layer material is copper, and the outer layer material is steel.

5. The arc heating simulation and measurement device according to claim 1, characterized in that, The nozzle (3) has a variable inner diameter structure. The small end of the cavity is connected to the inner cavity of the mixing chamber (2), and the large end of the cavity is connected to the inner cavity of the guide tube (4).

6. The device for simulating and measuring the thermo-electric properties based on electric arc heating according to claim 5, characterized in that, The nozzle (3) is a water-cooled sandwich structure, with the inner shell made of copper and the outer wall of the inner shell being a thin-walled reinforced structure.

7. The device for simulating and measuring the thermo-electric properties based on electric arc heating according to claim 1, characterized in that, The cross-section of the internal cavity of the model component is rectangular, and the model (5) is a rectangular flat plate structure. The three sides of the flat plate structure are connected to the bottom side of the conduit (4) and the two side walls of the conduit (4) respectively, forming a whole, and the two flat plate structures are set opposite to each other.

8. The device for simulating and measuring the thermo-electric properties based on electric arc heating according to claim 1, characterized in that, It also includes a linear track system (16), on which the antenna assembly and the focusing lens assembly are coaxially mounted. The first antenna (10), the second antenna (13), the first focusing lens (11) and the second focusing lens (12) can move along the linear track system. The linear track system (16) adopts an electric servo scanning mechanism.

9. The device for simulating and measuring the thermo-electric properties based on electric arc heating according to claim 1, characterized in that, It also includes a heat insulation frame (6) and a pressure frame (7), which are set at the end of the model (5). The heat insulation frame (6) insulates the model (5) and the pressure frame (7) is used to press and seal it.

10. The device for simulating and measuring the thermo-electric properties based on electric arc heating according to claim 1, characterized in that, It also includes a first temperature measuring device (8) and a second temperature measuring device (9), which are used to measure the back temperature of the two models (5), respectively; the first temperature measuring device (8) and the second temperature measuring device (9) both adopt K-type platinum-rhodium thermocouples with a temperature range of 0 to 1300℃.

11. The device for simulating and measuring the thermo-electric properties based on electric arc heating according to claim 10, characterized in that, The surface temperature of model (5) is calculated based on the back surface temperature of model (5) using the following formula: Among them, T s T represents the surface temperature of the model. w ν is the temperature at the back of the model, k is the thermal conductivity, l is the model thickness, and q is the cold wall heat flux.

12. The device for simulating and measuring the thermo-electric properties based on electric arc heating according to claim 1, characterized in that, The first antenna (10) and the second antenna (13) are horn antennas; the first focusing lens (11) and the second focusing lens (12) are quartz biconvex lenses.

13. The device for simulating and measuring the thermo-electric properties based on electric arc heating according to claim 1, characterized in that, The electrodes of the electric arc heater (1) are ring electrodes. By combining multiple ring electrodes, the current is divided into arcs during operation, and the total current is evenly distributed to a single ring electrode to minimize electrode erosion.

14. The device for simulating and measuring the thermo-electric properties based on electric arc heating according to claim 1, characterized in that, The signal transmission and acquisition frequency range of the processor (15) is 1 to 50 GHz, and the time acquisition frequency of the 1 to 50 GHz spectrum map is ≥0.1 frames / s.

15. The device for simulating and measuring the thermo-electric properties based on electric arc heating according to claim 1, characterized in that, The processor (15) receives reflected signals from the first antenna (10) in real time and transmitted plane wave signals from the second antenna (13) in real time. It calculates the transmittance change and dielectric constant of the model (5) under high temperature conditions, including: δ=10(S21'—S21") / 10 Where δ is the transmittance change at high temperature, ε is the dielectric constant, d is the thickness of the plate model, λ0 is the incident wave frequency, S11 is the reflected signal, S21 is the transmitted plane wave signal, S21' is the transmitted plane wave signal at the end of the test, and S21" is the average value of the transmitted plane wave signal within n seconds before the start of the test, where n is 0.5-1s.

16. The device for simulating and measuring the thermo-electric properties based on electric arc heating according to claim 1, characterized in that, It also includes a transmission cable (14), through which the processor (15) is connected to the first antenna (10) and the second antenna (13) for signal transmission.

17. A method for simulating and measuring the thermo-electric properties based on electric arc heating, characterized in that, The apparatus used in any one of claims 1 to 15 comprises: Arc is ignited in the arc heater (1), and a breakdown is made between the anode and cathode of the arc heater (1) to establish an arc channel and heat the incoming test medium. Cold gas medium is introduced into the mixing chamber (2) and mixed with the heated test medium flowing in from the electric arc heater (1). The inflow parameters and uniformity of the test medium are adjusted. Then the test medium flows into the nozzle (3) and is expanded and accelerated by the nozzle (3) to generate a supersonic airflow. The supersonic airflow flows into the model assembly to heat the two models (5) that are set up opposite each other, and then the supersonic airflow is discharged into the atmosphere. The signal output terminal of the processor (15) outputs an electromagnetic wave signal and transmits it to the first antenna (10). The first antenna (10) radiates the electromagnetic wave signal into space as a plane wave and simultaneously returns a reflected signal to the processor (15). The plane wave is focused by the first focusing lens (11) and then transmitted through the model (5). The transmitted plane wave signal is focused by the second focusing lens (12), received by the second antenna (13), and then sent to the signal receiving terminal of the processor (15) in real time. The processor (15) calculates the transmittance change and dielectric constant of model (5) under high temperature conditions based on the received reflected signal and the transmitted plane wave signal.

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