Thermal deformation test device for simulating composite material in space environment

Abstract

The invention discloses a space environment simulation composite material thermal deformation test device in the technical field of fiber composite materials, the space environment simulation composite material thermal deformation test device comprises a vacuum tank and a vacuum pump, the vacuum tank is divided into an upper tank body and a lower tank body from top to bottom, and the inner bottom wall of the lower tank body is provided with a placing assembly for placing a composite material; an observation assembly for acquiring a thermal deformation image of the composite material is mounted at the top end of the upper tank body; a radiation assembly for simulating a space radiation environment is mounted on the inner top wall of the upper tank body; a plurality of infrared heating plates are embedded in the inner side wall of the upper tank body and are distributed in an annular array; and a plurality of cold radiation plates are embedded in the inner side wall of the upper tank body. The vacuum tank is divided into the upper tank body and the lower tank body, the infrared heating plates and the cold radiation plates which are distributed in an annular array mode are combined (adjacent arrangement), temperature environment simulation of cold radiation-heat radiation alternation is achieved, and the space radiation-based heat exchange mechanism is met; and a test condition better fitting a real on-orbit working condition is provided for the thermal deformation performance test of the composite material.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fiber composite materials, and in particular to a space environment simulation composite material thermal deformation test device. BACKGROUND

[0002] The thermal deformation of fiber composite materials (such as carbon fiber / resin base, glass fiber / ceramic base, etc.) is fundamentally different from that of homogeneous materials such as metals. It is composed of two or more materials, such as "fiber" and "matrix". The thermal expansion coefficients and thermal conductivity of the two are significantly different, and the directional arrangement of the fibers will cause anisotropic deformation, and even special phenomena such as "interface stress-induced warping and delamination". Such materials are widely used in the field of spacecraft (such as satellite antenna reflectors, skin structures, support components, etc.), and the extreme nature of the space environment (vacuum degree ≤1×10⁻³Pa, temperature difference up to-150~150℃, ultraviolet / proton radiation coupling, alternating mechanical load) will further amplify the complexity of its thermal deformation. For example, at low temperatures, the imbalance between the shrinkage of the resin matrix and the constraint of the fiber may cause interfacial debonding, and the aging of the matrix caused by outgassing in a vacuum environment will change the thermal expansion coefficient, and rapid cold-hot alternation may cause cumulative warping of the laminate, directly affecting the assembly accuracy and on-orbit life of the spacecraft.

[0003] However, the existing simulation test device still has many limitations in testing the space thermal deformation of fiber composite materials, for example: most devices can only achieve single-temperature or vacuum environment simulation, and cannot simultaneously integrate "cold radiation-thermal radiation alternation" and "radiation-mechanical load superposition" typical space scenarios. For example, some devices use liquid nitrogen to achieve low temperature, which can easily damage the vacuum environment and cannot simulate the radiation-based heat dissipation mechanism in space; or although mechanical load can be applied, the load direction and cold-hot radiation path are structurally interfered, resulting in a temperature field uniformity deviation of more than ±5℃ during "thermal-mechanical coupling" testing, which cannot reflect the deformation response of the material under true on-orbit conditions.

[0004] Therefore, the present application proposes a space environment simulation composite material thermal deformation test device to solve the above problems. SUMMARY

[0005] To solve the above problems, the present application discloses a space environment simulation composite material thermal deformation test device, which realizes "cold radiation-thermal radiation alternation" temperature environment simulation, which is consistent with the radiation-based heat exchange mechanism in space, and provides more test conditions that are closer to true on-orbit conditions for thermal deformation performance testing of composite materials.

[0006] To achieve the above objectives, the technical solution of the present invention is as follows: a space environment simulation composite material thermal deformation test device, comprising a vacuum tank and a vacuum pump, wherein the vacuum pump is connected to the interior of the vacuum tank, characterized in that the vacuum tank is divided into an upper tank and a lower tank from top to bottom, wherein a placement component for placing composite materials is provided on the bottom wall of the lower tank; an observation component for acquiring thermal deformation images of composite materials is installed on the top of the upper tank; and a radiation component for simulating the space radiation environment is installed on the top wall of the upper tank. The inner circumference of the lower end of the upper tank is greater than the inner circumference of the upper end of the upper tank; several infrared heating plates are embedded in the inner wall of the upper tank and the infrared heating plates are distributed in a ring array; several cold radiation plates are embedded in the inner wall of the upper tank, and each cold radiation plate is located between two adjacent infrared heating plates.

[0007] Basic Scheme Principle: A vacuum pump evacuates the vacuum chamber to a space-grade vacuum environment (simulating space vacuum conditions). Functional components are integrated through a partitioned layout of upper and lower chambers: the lower chamber's placement component stably supports the composite material sample; the observation component at the top of the upper chamber acquires real-time images of the sample's thermal deformation; and the radiation component on the inner top wall simulates the ultraviolet and proton radiation environment of space. Crucially, the alternating operation of infrared heating plates (providing thermal radiation) and cold radiation plates (arranged adjacently to provide low-temperature radiation) distributed in a ring array on the side wall of the upper chamber achieves a temperature cycle of "thermal radiation - cold radiation." Combined with the flared structure at the lower end of the upper chamber (increasing the radiation contact range between the side wall and the sample), the extreme temperature difference environment of space, dominated by radiation, is reproduced, thus allowing for the testing of the composite material's thermal deformation characteristics under multi-environment coupling.

[0008] The above-mentioned solution has the following advantages: 1. Compared with the existing technology, this solution replaces the traditional method of cooling by spraying liquid nitrogen by using the radiative alternation of cold radiation plate and infrared heating plate. It does not require the introduction of a medium into the vacuum tank, and can stably maintain the high vacuum state inside the vacuum tank (which matches the vacuum characteristics of space). At the same time, it accurately simulates the temperature difference environment in space where "radiation is the main heat transfer method", and more realistically reflects the on-orbit thermal deformation behavior of composite materials. 2. The flared structure at the lower end of the upper tank, combined with the alternating ring layout of the infrared heating plate and the cold radiation plate, can increase the uniformity of the heating / cold radiation coverage of the sample, while avoiding optical path / spatial interference between the radiation component, the observation component and the hot and cold module; the adjacent hot and cold radiation plates make it easier to quickly switch between hot and cold conditions, effectively reduce the temperature field uniformity deviation, and ensure that the collected thermal deformation data is more in line with reality.

[0009] Furthermore, the placement assembly includes a lifting platform fixedly connected to the bottom wall of the lower tank, with a placement platform horizontally fixedly connected to the output end of the lifting platform, and the placement platform being located at the center of the lower tank.

[0010] Beneficial effects: The lifting platform can be adjusted in height to accommodate composite material samples of different thicknesses or sizes (such as thin plates, irregularly shaped supports, etc.), ensuring that the sample is always in the "uniform action zone" of the infrared heating plate, cold radiation plate and radiation components of the upper tank (avoiding local radiation intensity deviation caused by the sample being too high or too low); the placement platform is located in the center of the lower tank, which can make the distance between the sample and the surrounding cold and hot radiation plates and heating plates equal, reducing the temperature field unevenness caused by positional deviation, thereby improving the symmetry and data reliability of the thermal deformation test.

[0011] Furthermore, the top of the placement platform has several grooves.

[0012] Beneficial effects: The grooves reduce the direct contact area between the sample and the stage (e.g., from planar contact to "grooved point / line contact"), reducing thermal conduction interference between the two. This prevents the stage from altering the sample's bottom temperature through contact conduction due to its own temperature fluctuations (e.g., cooling caused by a cold radiation plate), ensuring that the sample primarily exchanges heat with the surrounding environment through radiation (more in line with the heat transfer mechanism under space vacuum). At the same time, the grooves can accommodate tiny protrusions during sample thermal deformation (e.g., local bulging of resin-based composite materials after heating), avoiding rigid constraints of the stage plane on sample deformation, or reducing displacement interference caused by friction between the sample and the stage due to deformation, ensuring accurate acquisition of deformation images by the observation components.

[0013] Furthermore, the observation component includes an observation through hole at the top of the upper tank, with an isolation cylinder fixedly connected inside the observation through hole; a protective cover is detachably connected to the top of the upper tank, and an image sensor is detachably connected to the bottom of the protective cover. The image sensor is located inside the isolation cylinder and corresponds to the placement stage.

[0014] Beneficial effects: The isolation cylinder can achieve sealed isolation between the inside and outside of the vacuum chamber (preventing the vacuum environment from directly affecting the image sensor), while providing a stable installation space for the image sensor and reducing the impact of temperature fluctuations caused by alternating hot and cold temperatures inside the vacuum chamber on the sensor's accuracy; the detachable design of the protective cover and the image sensor facilitates the installation, debugging, replacement, and maintenance of the sensor (such as replacing cameras with different resolutions according to testing requirements); the image sensor corresponds to the placement stage, allowing for precise alignment with the sample and ensuring that the thermal deformation image acquisition range covers the entire sample area (especially avoiding missed images at the edges), thus improving the integrity of the deformation data.

[0015] Furthermore, the radiation assembly includes several UV radiation sources and several proton beam emitting devices.

[0016] Beneficial effects: UV radiation sources can simulate ultraviolet radiation in space (such as the scenario of a spacecraft being exposed to ultraviolet radiation from the sun), while proton beam emitters can simulate high-energy proton radiation in space. The combination of the two can reproduce the "multi-type radiation coupling" environment in space. By working in synergy or individually with the two radiation sources, the changes in the thermal deformation characteristics of composite materials under radiation can be tested (such as the change in the coefficient of thermal expansion of the resin matrix after aging caused by UV radiation, and the difference in warping after stress concentration at the interface caused by proton radiation). Compared with single radiation simulation, it is closer to the real space environment and provides more comprehensive experimental data for the on-orbit performance degradation assessment of materials.

[0017] Furthermore, each infrared heating plate has a baffle on its surface, and the baffles are all made of quartz glass.

[0018] Beneficial effects: Quartz glass has good infrared transmittance (transmittance of infrared radiation ≥90%), which will not hinder the heat radiation transfer of the infrared heating plate and ensure that the heating efficiency is not affected; at the same time, the baffle can physically isolate the infrared heating plate from the internal space of the vacuum chamber, avoid the composite material sample from directly contacting the heating plate during thermal deformation (such as warping or bulging) and causing local overheating, or prevent residual impurities in the vacuum chamber (such as particles generated by material release) from adhering to the surface of the heating plate and affecting the heating uniformity.

[0019] Furthermore, the inner side wall of the upper tank is equipped with several cleaning components that correspond one-to-one with the cold radiation plates. These cleaning components are used to remove the frost layer on the surface of the cold radiation plates.

[0020] Beneficial effects: During long-term operation, residual moisture inside the vacuum chamber can easily condense on the surface of the cold radiation plate, significantly reducing its emissivity, leading to decreased cooling efficiency and increased temperature field uniformity deviation. The cleaning assembly can promptly remove the frost, maintaining the high radiation efficiency of the cold radiation plate and ensuring stable low-temperature radiation to the sample (e.g., cooling rate fluctuations controlled within ±1℃ / min). Simultaneously, it prevents frost accumulation from causing "temperature lag" during the alternating operation of the cold radiation plate and the infrared heating plate, ensuring accurate reproduction of alternating hot and cold conditions, thereby improving the repeatability and reliability of composite material thermal deformation test data.

[0021] Furthermore, each cleaning component includes a sliding groove corresponding to a cold radiation plate, and a cleaning rod is slidably fitted inside each sliding groove. A cleaning layer is provided on the side of the cleaning rod closest to the cold radiation plate, and the cleaning layer is in contact with the surface of the cold radiation plate. Telescopic rods are fixedly connected to both ends of the cleaning rods, and pistons are fixedly connected to the ends of the telescopic rods away from the cleaning rods. The pistons are slidably fitted with telescopic cavities opening inside the upper tank. Several induction tanks corresponding to the cold radiation plates are provided on the inner side wall of the lower tank, and the induction tanks are all connected to the corresponding telescopic cavities.

[0022] Beneficial effects: This cleaning component senses the frost state of the cold radiation plate through the induction tank (e.g., a decrease in the temperature of the cold radiation plate triggers a change in the physical state of the medium inside the induction tank). Utilizing the pressure difference between the telescopic chamber and the piston, it drives the telescopic rod to reciprocate along the sliding groove, achieving mechanical removal of the frost layer. No additional electronic control components are required, making it suitable for extreme environments such as vacuum and high / low temperatures (avoiding the risk of electronic component failure). The cleaning layer is in close contact with the surface of the cold radiation plate, allowing for targeted removal of frost from each plate, ensuring consistent radiation efficiency across all plates (avoiding temperature field deviations caused by localized frost residue). The overall structure is highly integrated with the vacuum tank, without interfering with the normal operation of infrared heating and radiation simulation, achieving automated and precise frost removal and ensuring the stability of the cold radiation effect during long-term testing.

[0023] Furthermore, several temperature sensors are installed on the top of the placement platform.

[0024] Beneficial effects: The feedback signal from the temperature sensor can be used for closed-loop control of the working status of the infrared heating plate and the cold radiation plate, achieving precise adjustment of the target temperature (such as automatically correcting the heating / cooling power when the temperature difference fluctuation exceeds the threshold), and improving the controllability and data reliability of the experiment.

[0025] Furthermore, the top surface of the placement platform is coated with a ceramic heat-insulating coating.

[0026] Beneficial effects: The ceramic thermal insulation coating has an extremely low thermal conductivity (typically <0.1 W / (m・K)), which can significantly weaken the heat conduction path between the placement stage and the bottom of the composite sample. This prevents the temperature of the sample bottom from changing through contact conduction when the placement stage experiences temperature fluctuations due to indirect influence from the cold radiation plate or infrared heating plate (such as preventing the placement stage from "absorbing" heat from the sample bottom at low temperatures or conducting additional heat to the sample bottom at high temperatures). This ensures that the sample mainly exchanges heat with the surrounding environment through radiation (which is more in line with the "radiation-based" heat transfer mechanism in the vacuum of space). Attached Figure Description

[0027] Figure 1 This is an overall isometric view of an embodiment of a space environment simulation composite material thermal deformation testing device of the present invention; Figure 2 This is an overall side sectional view of an embodiment of a space environment simulation composite material thermal deformation testing device of the present invention; Figure 3 This is an enlarged view of part A of an embodiment of a space environment simulation composite material thermal deformation testing device of the present invention; Figure 4 This is an enlarged view of part B of an embodiment of a space environment simulation composite material thermal deformation test device of the present invention; Figure 5This is a schematic diagram of the cleaning component of an embodiment of a space environment simulation composite material thermal deformation test device of the present invention.

[0028] List of reference numerals in the attached diagram: 1. Lower tank; 2. Upper tank; 3. Isolation cylinder; 4. Image sensor; 5. Protective cover; 6. UV radiation source; 7. Proton beam emitting device; 8. Placement platform; 9. Lifting platform; 10. Sealing door; 11. Cold radiation plate; 12. Infrared heating plate; 13. Baffle; 14. Cleaning rod; 15. Vacuum pump; 16. Telescopic rod; 17. Sliding groove; 18. Telescopic cavity; 19. Induction tank. Detailed Implementation

[0029] The present invention will be further illustrated below with reference to the accompanying drawings and specific embodiments. It should be understood that the following specific embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. It should be noted that the terms "front," "rear," "left," "right," "up," and "down" used in the following description refer to directions in the accompanying drawings, and the terms "inner" and "outer" refer to directions toward or away from the geometric center of a specific component, respectively. Example

[0030] like Figure 1 and Figure 2 As shown, a space environment simulation composite material thermal deformation test device includes a vacuum tank, a vacuum pump 15, and a controller. The vacuum pump 15 is connected to the inside of the vacuum tank. A sealing door 10 is provided on one side of the vacuum tank. The vacuum tank is divided into an upper tank body 2 and a lower tank body 1 from top to bottom. A lifting platform 9 is screwed to the bottom wall of the lower tank body 1. A placement platform 8 is horizontally fixed to the output end of the lifting platform 9 and is located at the center of the lower tank body 1. At the same time, several grooves are opened at the top of the placement platform 8, which can reduce the direct contact area between the sample and the placement platform 8 (such as changing the planar contact to "grooved point / line contact"), reducing the thermal conduction interference between the two. Secondly, clamps can be installed in the grooves to clamp some fiber composite material samples.

[0031] In addition, this scheme uses the DIC digital image correlation method to detect sample deformation. Specifically, a circular observation through hole is opened at the center of the top of the upper tank 2. An isolation cylinder 3 (the cylinder wall is made of alloy material and the top is flush with the top surface of the upper tank 2) is sealed and welded inside the through hole. An optical glass window (vacuum resistant and with good light transmission) is coaxially installed inside the isolation cylinder 3. A protective cover 5 is detachably connected to the top of the upper tank 2 through a vacuum flange. An image sensor 4 (such as a high-speed CCD camera) is fixed to the bottom of the protective cover 5 through an adjustment bracket. The lens of the image sensor 4 faces the optical glass window, and the lens axis of the image sensor 4 coincides with the center of the placement stage 8. The thermal deformation image of the sample on the placement stage 8 can be stably acquired through the isolation cylinder 3, avoiding the influence of the vacuum environment on the image sensor 4.

[0032] Meanwhile, several UV radiation sources 6 and several proton beam emitting devices 7 are installed on the inner top wall of the upper tank 2. For example, four UV radiation sources 6 (wavelength 200~400nm, power adjustable) and two proton beam emitting devices 7 are set. Both the UV radiation sources 6 and the proton beam emitting devices 7 are installed at an angle downwards via brackets (15° with the vertical direction). The emission direction is directed towards the center of the placement stage 8, and the positions are staggered from the infrared heating plate 12 and the cold radiation plate 11 (spacing ≥10cm) to ensure that the ultraviolet radiation and proton beam can directly act on the sample surface without blocking the radiation path of the infrared heating plate 12 and the cold radiation plate 11.

[0033] To address the issue that some existing devices use liquid nitrogen injection to achieve cryogenics, which easily disrupts the vacuum environment and fails to simulate the radiation-based heat dissipation mechanism in space, this solution specifically addresses this problem: the inner circumference of the lower end of the upper tank 2 is greater than the inner circumference of the upper end of the upper tank 2; combined with... Figure 2 and Figure 3 As shown, several infrared heating plates 12 are embedded in the inner wall of the upper tank 2, and the infrared heating plates 12 are arranged in a ring array. Several cold radiation plates 11 are also embedded in the inner wall of the upper tank 2. The number of cold radiation plates 11 is the same as that of infrared heating plates 12, and they are arranged alternately. That is, a cold radiation plate 11 is set between each two adjacent infrared heating plates 12. The two form a complete ring-shaped structure along the inner wall of the upper tank 2. The installation height of the cold radiation plates 11 and the infrared heating plates 12 is the same, which corresponds to the height of the placement platform 8 in the lower tank 1 (for example, the vertical distance from the top of the placement platform 8 is 30~50cm), ensuring that a uniform surrounding hot and cold alternating radiation field is formed on the fiber composite material sample on the placement platform 8. Secondly, baffles 13 are fixed on the surface of the infrared heating plate 12 near the inside of the vacuum tank. The baffles 13 are made of quartz glass with a thickness of 3-5mm. The edges of the baffles 13 are embedded in the inner wall of the upper tank 2. The baffles 13 completely cover the radiation surface of the infrared heating plate 12, which does not affect the penetration of infrared radiation (quartz glass has a transmittance of ≥90% for the infrared band) and can isolate the sample from direct contact with the heating plate, so as to avoid the sample from touching the heating plate when it is thermally deformed (such as warping or bulging) and causing local overheating. The main body of the cold radiation plate 11 is a hollow copper plate (with a serpentine flow channel inside). The flow channel is connected to the external low-temperature medium supply system (such as a liquid nitrogen storage tank, a low-temperature circulating pump, etc., all of which are electrically connected to the controller) through a vacuum-sealed pipe. The low-temperature medium (such as -196℃ liquid nitrogen or -150℃ low-temperature coolant) circulates in the flow channel, and the surface of the cold radiation plate 11 is kept at a set low temperature (such as -150~-50℃) through heat conduction. At the same time, the surface of the cold radiation plate 11 is coated with a high emissivity black coating (such as a carbon-based matte coating with an emissivity ≥0.95) to ensure that it can efficiently emit low-temperature radiation to the sample.

[0034] The vacuum pump 15, UV radiation source 6, proton beam emitting device 7, image sensor 4, temperature sensor, infrared heating plate 12 and cold radiation plate 11 are all electrically connected to the controller.

[0035] Specifically, the cryogenic medium circulates only within the cold radiation plate 11, without needing to be directly injected into the vacuum chamber. Therefore, no gas is generated due to liquid nitrogen evaporation, and a stable high vacuum environment (vacuum degree ≤1×10⁻³Pa) can be maintained inside the chamber, matching the vacuum characteristics of space. At the same time, the cold radiation plate 11 cools the sample through "radiative heat transfer"—the sample emits thermal radiation to the cryogenic cold radiation plate 11, and its own heat is lost through radiation (which is completely consistent with the mechanism of heat dissipation by spacecraft to the low-temperature cosmic background in the space environment), rather than through convection or conduction (traditional liquid nitrogen injection relies on contact conduction between liquid nitrogen and the sample, which is very different from the heat transfer method in space). This can more realistically reproduce the heat dissipation process of composite materials in space. The cold radiation plate 11 and the infrared heating plate 12 are arranged in an alternating ring (both are equidistant from the sample), and can be independently controlled by the controller to achieve rapid switching between "thermal radiation" and "cold radiation" (e.g., a cycle every 30 minutes): when the infrared heating plate 12 is working, it transfers heat to the sample through infrared radiation (simulating the spacecraft's sun-facing side being heated by solar radiation); when the cold radiation plate 11 is working, it cools the sample through low-temperature radiation (simulating the spacecraft's shaded side being cooled by cosmic background radiation).

[0036] Several temperature sensors are installed at the top of the placement stage 8. These sensors are preferably miniature patch thermocouples (accuracy ±0.5℃, response time ≤1s). The number of sensors is set to 3-6 depending on the sample size, and they are radially distributed along the center of the placement stage 8 (e.g., one in the center and four evenly distributed around the circumference at 20mm from the center). The sensing ends of the temperature sensors are flush with the top surface of the placement stage 8. When the fiber composite material sample is placed on the placement stage 8, the temperature sensors can directly contact the bottom of the sample, collecting temperature data in real time from different areas of the sample (e.g., the central area, edge areas, and key locations with different fiber orientations). Simultaneously, the top surface of the placement stage 8 is coated with a ceramic heat-insulating coating, which increases the contact thermal resistance between the placement stage 8 and the sample. This ensures that the heat exchange of the sample mainly relies on the infrared heating plate 12 / cold radiation plate 11 of the upper tank 2 (radiative heat exchange) rather than contact conduction with the placement stage 8 (closer to the heat transfer characteristics of a vacuum environment in space). Example

[0037] Unlike the previous embodiment, when the cold radiation plate 11 operates for a long time, residual water vapor inside the vacuum chamber easily condenses on its surface to form a frost layer. This frost layer has a loose and porous structure, which significantly reduces the emissivity of the cold radiation plate 11 (from above 0.95 to below 0.5). This results in a significant decrease in its efficiency in transmitting low-temperature radiation to the sample, which not only prolongs the time it takes for the sample to reach the target low temperature, but also causes a significant deviation in the temperature field surrounding the sample due to the uneven thickness of the frost layer on each cold radiation plate 11 (e.g., the frost layer on the edge cold radiation plates 11 is thicker than that in the center). This deviation leads to inconsistent thermal deformation in different parts of the composite material sample, directly interfering with the observation components' capture of the thermal deformation pattern and affecting the reliability of the test data. Therefore, this embodiment adds a cleaning component to specifically remove the frost layer.

[0038] Specifically, such as Figure 2 , Figure 4 and Figure 5 As shown, each cleaning component includes a sliding groove 17 corresponding to a cold radiation plate 11. A cleaning rod 14 is slidably fitted within each sliding groove 17. A cleaning layer is provided on the side of each cleaning rod 14 closest to the cold radiation plate 11, and this cleaning layer is in contact with the surface of the cold radiation plate 11. Telescopic rods 16 are welded to both ends of each cleaning rod 14, and a piston is integrally formed at the top of each telescopic rod 16 (e.g., ...). Figure 5 As shown), the pistons are slidably fitted with telescopic cavities 18 inside the upper tank 2; the inner wall of the lower tank 1 is welded with several induction tanks 19 corresponding one-to-one with the cold radiation plate 11 (preferably titanium alloy TC4, which can be used for a long time in the temperature range of -250℃ to 600℃, and can completely cover the working temperature difference between the cold radiation plate (down to -150℃) and the infrared heating plate (up to 200℃), and will not become brittle or crack due to hot and cold cycles). The induction tanks 19 are all connected to the corresponding telescopic cavities 18, and the connecting pipes between the induction tanks 19 and the telescopic cavities 18 are designed according to the actual design situation, for example: distributed on the outside of the lower tank 1 and the upper tank 2.

[0039] Specifically, the induction canister 19 is filled with an inert gas (such as nitrogen), and the outer wall of the induction canister 19 corresponds to the radiation area of ​​the corresponding cold radiation plate 11 and the adjacent infrared heating plate 12. When the cold radiation plate 11 is working (maintaining a low temperature radiation state), the heat on the surface of the induction canister 19 is absorbed by the cold radiation plate 11 through radiation, the internal temperature of the induction canister 19 decreases, and the inert gas in the induction canister 19 contracts due to the cooling, causing the air pressure in the telescopic cavity 18 connected to the induction canister 19 to decrease synchronously. At this time, the piston in the telescopic cavity 18 is subjected to the external atmospheric pressure (or the preset pressure outside the cavity) and slides upward along the telescopic cavity 18. The piston drives the telescopic rod 16 to move upward synchronously. The telescopic rod 16 pulls the cleaning rod 14 to move upward along the sliding groove 17 towards the cold radiation plate 11. The cleaning layer (such as perfluoroether rubber) on one side of the cleaning rod 14 is tightly attached to the surface of the cold radiation plate 11 and scrapes off the frost layer condensed on the surface as the cleaning rod 14 slides.

[0040] Because the cold radiation plate 11 and the adjacent infrared heating plate 12 are temperature isolated during actual operation, for example by filling with multi-layer insulation material (MLI), the infrared heating plate 12 has a smaller impact on the cold radiation plate 11 after alternating between hot and cold. Therefore, when the infrared heating plate 12 is working (switching to thermal radiation mode), the infrared radiation heat it generates is transferred to the induction tank 19 (or directly heats the outer wall of the induction tank 19). The inert gas in the tank expands due to the temperature rise, and the increased volume pushes the gas into the telescopic cavity 18 along the connecting pipe, causing the gas pressure in the telescopic cavity 18 to rise. The high-pressure gas pushes the piston to slide downward along the telescopic cavity 18, and the piston drives the telescopic rod 16 to move downward synchronously. The telescopic rod 16 pushes the cleaning rod 14 to move downward along the sliding groove 17 towards the cold radiation plate 11. The cleaning layer slides against the surface of the cold radiation plate 11 again, and the residual frost layer is scraped off a second time.

[0041] The technical means disclosed in this invention are not limited to those disclosed in the above embodiments, but also include technical solutions composed of any combination of the above technical features.

Claims

1. A space environment simulation composite thermal distortion test apparatus comprising a vacuum tank and a vacuum pump (15) in communication with the interior of the vacuum tank, characterized in that, The vacuum tank is divided into an upper tank body (2) and a lower tank body (1) from top to bottom, the inner bottom wall of the lower tank body (1) is provided with a placing assembly for placing composite materials; the top end of the upper tank body (2) is provided with an observation assembly for obtaining thermal deformation images of the composite materials; the inner top wall of the upper tank body (2) is provided with a radiation assembly for simulating a space radiation environment; the inner circumference of the lower end of the upper tank body (2) is larger than that of the upper end of the upper tank body (2); a plurality of infrared heating plates (12) are embedded in the inner side wall of the upper tank body (2) and are arranged in a ring array; a plurality of cold radiation plates (11) are embedded in the inner side wall of the upper tank body (2), and each cold radiation plate (11) is located between two adjacent infrared heating plates (12).

2. The space environment simulated composite thermal distortion test device according to claim 1, characterized in that: The placing assembly comprises a lifting platform (9) fixedly connected to the inner bottom wall of the lower tank body (1), and the output end of the lifting platform (9) is fixedly connected with a placing table (8) horizontally, and the placing table (8) is located at the center position of the lower tank body (1).

3. The space environment simulated composite thermal distortion test apparatus of claim 2, wherein: A plurality of grooves are formed in the top end of the placing table (8).

4. The space environment simulated composite thermal distortion test apparatus of claim 1, wherein: The observation assembly comprises an observation through hole formed in the top end of the upper tank body (2), and an isolation cylinder (3) is fixedly connected in the observation through hole; a protective cover (5) is detachably connected to the top end of the upper tank body (2), and an image sensor (4) is detachably connected to the bottom end of the protective cover (5), the image sensor (4) is located in the isolation cylinder (3), and the image sensor (4) corresponds to the placing table (8).

5. The space environment simulated composite thermal distortion test apparatus of claim 1, wherein: The radiation assembly comprises a plurality of UV radiation sources (6) and a plurality of proton beam emitting devices (7).

6. The space environment simulated composite thermal distortion test apparatus of claim 1, wherein: The surface of each infrared heating plate (12) is provided with a baffle (13) made of quartz glass.

7. The space environment simulated composite thermal distortion test apparatus of claim 1, wherein: The inner side wall of the upper tank body (2) is provided with a plurality of cleaning assemblies corresponding to the cold radiation plates (11) one by one, and each cleaning assembly is used for removing the frost layer on the surface of the cold radiation plate (11).

8. The space environment simulated composite thermal distortion test apparatus of claim 7, wherein: Each cleaning assembly comprises a sliding groove (17) corresponding to the cold radiation plate (11) one by one, a cleaning rod (14) is slidingly matched in the sliding groove (17), a cleaning layer is arranged on the side of the cleaning rod (14) close to the cold radiation plate (11), and the cleaning layer is in contact with the surface of the cold radiation plate (11); the two ends of the cleaning rod (14) are fixedly connected with telescopic rods (16), the ends of the telescopic rods (16) away from the cleaning rod (14) are fixedly connected with pistons, and the pistons are slidingly matched with telescopic cavities (18) formed in the inner part of the upper tank body (2); the inner side wall of the lower tank body (1) is provided with a plurality of induction tanks (19) corresponding to the cold radiation plates (11) one by one, and the induction tanks (19) are in communication with the corresponding telescopic cavities (18).

9. The space environment simulated composite thermal distortion test apparatus of claim 2, wherein: A plurality of temperature sensors are arranged on the top end of the placing table (8).

10. The space environment simulated composite thermal distortion test apparatus of claim 2, wherein: The top end surface of the placing table (8) is coated with a ceramic heat insulation coating.

Images