Infrared spectrum regulation and control aerogel vacuum insulation board doped with extinction phase change fibers and application of infrared spectrum regulation and control aerogel vacuum insulation board doped with extinction phase change fibers

Abstract

The invention discloses an infrared spectrum regulation and control aerogel vacuum insulation board utilizing sub-band doped extinction phase change fibers and application of the infrared spectrum regulation and control aerogel vacuum insulation board, and belongs to the technical field of high-temperature thermal protection of spacecrafts. The vacuum heat insulation plate comprises an aerogel core material and a vacuum packaging shell layer wrapping the aerogel core material, the aerogel core material is sealed in an approximately vacuum environment through the vacuum packaging shell layer, and the aerogel core material is formed by doping Al2O3 aerogel with at least three layers of extinction phase change fibers. According to the invention, the traditional solid fiber is transformed into the extinction phase change fiber, so that the defects of low strength, strong infrared light transmission, poor thermal inertia and the like of the existing aerogel thermal protection system are overcome; meanwhile, an opacifying agent is effectively replaced, and the problems caused by opacifying agent breakage in actual aerospace application are avoided; the structure change caused by phase change can improve the short-term heat insulation performance of the whole material on one hand, and can improve the extinction performance on the other hand, and on the basis, spectrum regulation is utilized to maximize the engineering application of the heat insulation performance of a thermal protection system.

Description

Technical Field

[0001] The present invention belongs to the technical field of high-temperature thermal protection of spacecraft, and specifically relates to an infrared spectrum control aerogel vacuum insulation board using sub-band doped extinction phase change fibers and its application. Background Art

[0002] Vacuum insulation panels are a type of vacuum insulation material that is composed of a filling material and a vacuum layer. While meeting the same insulation requirements, they can achieve a thinner insulation layer, a smaller volume, and a lighter weight. Aerogel, another super-strong insulation material, has been studied as a filling material encapsulated in vacuum insulation panels to form a new type of vacuum insulation panel. However, from the perspective of practical application of thermal insulation materials, it has several obvious defects: (1) The conventional vacuum insulation board filling material is SiO2 aerogel, but its internal particles fuse and the structure collapses at high temperatures, which limits its application under high temperature conditions; (2) Since aerogel is highly transparent to 3-8μm near-infrared radiation at high temperatures, its radiation heat transfer is significantly increased when used in high temperature environments; (3) Its own specific heat capacity is low, the temperature response is fast in non-steady-state heat transfer, the short-term thermal insulation performance is poor, and the thermal insulation capacity is insufficient; (4) There is a temperature gradient in the aerogel, different types of extinction materials have different extinction characteristics and temperature resistance, and there is a lack of effective doping methods; (5) The traditional doping method only performs multi-layer doping according to the optimal size, but ignores the corresponding optimal doping ratio, and the fact that the extinction characteristics of the fiber are related to the incident infrared wavelength.

[0003] Of course, the existing technology is also actively looking for solutions to the above-mentioned defective problems. For example, in order to solve the problem that SiO2 aerogel is easy to collapse at high temperatures, Al2O3 aerogel with stronger mechanical properties is used as a substitute. For example, in order to solve the problem of near-infrared transmittance, sunscreens such as SiC, TiO2 or SiO2 are usually doped to suppress near-infrared radiation. However, in aerospace applications, due to the sudden increase in surface air pressure, the sunscreen will quickly break within a few seconds, and the fibers are arranged at a specific angle to replace the sunscreen to inhibit near-infrared radiation heat transfer. For example, in order to solve the problem of poor short-term thermal insulation performance of aerogel, the phase change material is wrapped with a sunscreen material to support the fiber and doped into the aerogel matrix. However, the traditional doping method only performs multi-layer doping according to the optimal size, while ignoring the corresponding optimal doping ratio, and the extinction characteristics of the fiber are related to the incident infrared wavelength.

[0004] Therefore, the vacuum insulation panels of the prior art still have technical problems such as poor thermal insulation performance, radiant heat transfer and uncontrollable short-term thermal insulation due to the easy collapse of traditional silica aerogel and the rupture of sunscreen agents. Summary of the invention

[0005] In order to overcome the shortcomings of the above-mentioned prior art, the purpose of the present invention is to provide an infrared spectrum regulation aerogel vacuum insulation panel doped with phase change fibers and its application, which solves the shortcomings of the existing aerogel thermal protection vacuum insulation panel such as low strength, strong infrared light transmittance and poor thermal inertia; at the same time, it effectively replaces the sunshade and avoids the technical problems of poor thermal insulation performance, radiant heat transfer and uncontrollable short-term thermal insulation caused by the rupture of the sunshade in actual aerospace applications.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] The invention discloses an infrared spectrum control aerogel vacuum insulation board doped with extinction phase change fiber, comprising an aerogel core material and a vacuum packaging shell layer coated on the outside thereof, wherein the vacuum packaging shell layer seals the aerogel core material in a near-vacuum environment;

[0008] The aerogel core material is composed of Al2O3 aerogel doped with at least three layers of extinction phase change fibers, and the doped extinction phase change fibers account for 10% to 15% of the volume of the Al2O3 aerogel;

[0009] The vacuum packaging shell material is selected from a material that is resistant to high temperatures and has a matte property.

[0010] Preferably, the phase change fiber core material with extinction performance is a phase change material, including semiconductor oxides, organic phase change materials, metal alloys, etc., and its physical properties including phase change temperature, latent heat, extinction performance, etc. are selected according to the actual band and thermal insulation environment.

[0011] Preferably, at least three layers of doped extinction phase change fibers are arranged layer by layer from the short-wave band to the long-wave band according to the temperature concentration peak, so as to spectrally suppress the infrared radiation inside the insulation board when the temperature difference between the cold and hot surfaces of the insulation board is as high as 1000K.

[0012] Further preferably, the bands are divided into the following according to the peak concentration section:

[0013] Short wave band: 2.22~3.20μm, 900~1300K;

[0014] Medium band: 3.20~7.23μm, 400~900K;

[0015] Long wave band: 7.23~9.63μm, 300~400K.

[0016] Preferably, the phase change temperature, latent heat, volume fraction and extinction performance parameters of the extinction phase change fibers doped in the short-wave band, medium-wave band and long-wave band are set to high, moderate and low respectively; the doping volume fractions of the extinction phase change fibers doped in the short-wave band, medium-wave band and long-wave band decrease successively.

[0017] Further preferably, the infrared radiation is concentrated on the doped phase change fiber A at 2.22-3.20 μm, and A needs to satisfy the characteristics of high phase change temperature, high latent heat, high volume fraction, and excellent extinction performance; the phase change fiber B is doped at 3.20-7.23 μm, and B needs to satisfy the characteristics of medium phase change temperature, moderate latent heat, moderate volume fraction, and moderate extinction performance; the phase change fiber C is doped at 7.23-9.63 μm, and C needs to satisfy the characteristics of low phase change temperature, low latent heat, and low volume fraction.

[0018] Further preferably, the phase change temperature, latent heat, extinction characteristics and other physical properties of the phase change core material of the phase change fiber of each layer are determined by the actual incident band of the layer. When the incident band is between 2.22 and 3.20 μm (900 to 1300 K), metal alloy materials with high phase change temperature, high latent heat and excellent extinction characteristics such as magnesium silicon alloy can be selected; when the incident band is between 3.20 and 7.23 μm (400 to 900 K), organic phase change materials with moderate phase change temperature and latent heat such as zinc aluminum alloy can be selected; when the incident band is between 7.23 and 9.63 μm (300 to 400 K), semiconductor metal oxides with low phase change temperature and low latent heat such as vanadium dioxide can be selected.

[0019] More preferably, in the infrared spectrum range of 2.22 to 3.20 μm, a phase transition temperature of 1219 K and a latent heat of 757 kJ·kg -1 The magnesium-silicon alloy is used in the infrared spectrum range of 3.20-7.23 μm with a phase transition temperature of 710 K and a latent heat of 117 kJ·kg -1 The zinc-aluminum alloy is used in the infrared spectrum range of 7.23-9.63μm with a phase transition temperature of 341K and a latent heat of 43kJ·kg -1 VO2.

[0020] Further preferably, the doping volume fraction of the phase change fiber decreases from the short-wave band to the long-wave band, and the doping amounts of the three phase change fibers are 5% for A, 4% for B, and 2% for C.

[0021] Preferably, at least three layers of extinction phase change fibers are arranged at a specific 70° angle to spectrally selectively suppress infrared radiation in different wavelength bands according to different infrared radiation and the mechanism of improving extinction performance after the material phase change. The extinction performance of phase change fibers at specific angles is better than that of randomly doped traditional solid fibers, and can more effectively suppress radiation heat transfer and improve the high-temperature thermal insulation performance of aerogel composite materials - the internal core material absorbs heat at a constant temperature during the phase change process to delay transient heat transfer and improve the thermal inertia of the aerogel. Moreover, after the core material phase changes, the extinction characteristics of the material can be further improved within a specific infrared band to match the infrared spectral characteristics after temperature rise.

[0022] Furthermore, the outer diameter of the extinction phase change fiber is 4 to 6 μm.

[0023] Further preferably, the optimum outer diameter of the phase change fiber of each layer is 4 μm, and the optimum outer diameter value is determined by Mie scattering theory.

[0024] Furthermore, the inner and outer diameter ratio of the extinction phase change fiber is 0.95, which prevents the leakage of the core material, ensures the extinction performance and maximizes the effect of delaying transient heat transfer.

[0025] Furthermore, the vacuum packaging shell material is selected to have good light-shielding performance, such as SiC, TiO2, SiO2 and other high-temperature resistant materials.

[0026] Therefore, the shell material of the "phase change fiber" of the present invention is a material that is resistant to high temperatures and has extinction properties, and the core is a solid-liquid phase change material that has improved extinction performance after phase change and can absorb heat at a constant temperature, so as to overcome the disadvantage of aerogel's sharp increase in infrared radiation transmittance at high temperatures. When this material has a low equivalent thermal conductivity, it can also improve the problem of poor thermal inertia of aerogels. It can not only optimize the short-term thermal insulation performance of the aircraft thermal protection system through the constant temperature heat absorption of the phase change fiber, but also further improve the extinction performance after the phase change, and improve the temperature control ability of the thermal protection system within a limited thickness.

[0027] The invention also discloses the application of the infrared spectrum regulating aerogel vacuum insulation board doped with extinction phase change fiber in aerospace thermal protection system.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] The infrared spectrum control aerogel vacuum insulation board doped with extinction phase change fiber disclosed in the present invention firstly adopts Al2O3 aerogel with stronger mechanical properties at high temperature to replace the traditional SiO2 aerogel as the core filling material. Al2O3 aerogel has better mechanical properties in high temperature environment and its structure is not easy to collapse, so it is more suitable for high temperature conditions than SiO2 aerogel. At the same time, the aerogel core material is sealed in a near-vacuum environment by the vacuum packaging shell layer, which effectively avoids the heat transfer caused by the filling insulation material and the air convection, and can greatly reduce the thermal conductivity. Secondly, the addition of extinction phase change fiber in the aerogel core material can replace the sunscreen and play an excellent role in improving the mechanical properties of the material. The matting effect can effectively avoid a series of problems caused by the easy breakage of the sunscreen in practical applications. The use of matting phase change fiber has better matting performance than traditional SiO2 and TiO2 fibers, and the matting performance is further improved after the phase change; furthermore, the vacuum packaging shell material selects a high temperature resistant material with matting performance, which is coordinated with the aerogel core material for synergistic effect; finally, the aerogel core material of the present invention can also improve the poor thermal inertia problem of aerogel when it has a low equivalent thermal conductivity, and can not only optimize the short-term thermal insulation performance of the aircraft thermal protection system through the constant temperature heat absorption of the phase change fiber, but also can further improve the matting performance after the phase change, and improve the temperature control ability of the thermal protection system within a limited thickness. In summary, the vacuum insulation panel of the present invention solves the shortcomings of the existing aerogel thermal protection system such as low strength, strong infrared transmittance and poor thermal inertia by transforming the traditional solid fiber into the extinction phase change fiber; at the same time, it effectively replaces the sunscreen agent to avoid the problems caused by the cracking of the sunscreen agent in actual aerospace applications; the structural changes caused by the phase change will, on the one hand, improve the short-term thermal insulation performance of the overall material, and on the other hand, it can improve the extinction performance. On this basis, the spectral regulation is used to maximize the engineering application of the thermal insulation performance of the thermal protection system, which has strong practicality.

[0030] Furthermore, based on the improvement of the extinction performance and the delay of transient heat transfer mechanism of the extinction phase change fiber after phase change, the present invention performs spectral regulation according to the wavelength band in order to maximize the thermal insulation performance. At least three layers of doped extinction phase change fibers are arranged layer by layer from the short wavelength band to the long wavelength band according to the temperature concentration peak, and the spectrum is regulated according to the incident wavelength band in the aerogel matrix material, which has better thermal insulation performance than traditional doped single-layer phase change materials.

[0031] Furthermore, the inner and outer diameter ratio of the phase change fiber is 0.95, which prevents leakage of the core material, ensures the extinction performance and maximizes the effect of delaying transient heat transfer.

[0032] Furthermore, three or more layers of phase change fibers are doped into the aerogel and arranged at a specific angle of 70o to spectrally selectively suppress infrared radiation in different wavelength bands according to different infrared radiation and the mechanism of improving the extinction performance of the material after phase change. Experiments have shown that the extinction performance of phase change fibers at specific angles is better than that of traditional solid fibers doped randomly, and can more effectively suppress radiation heat transfer and improve the high-temperature thermal insulation performance of aerogel composite materials. The internal core material absorbs heat at a constant temperature during the phase change process to delay transient heat transfer and improve the thermal inertia of the aerogel. Moreover, after the core material phase changes, the extinction characteristics of the material can be further improved within a specific infrared band to match the infrared spectral characteristics after temperature rise. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 The structure schematic diagram of an infrared extinction aerogel vacuum insulation panel using sub-band doped phase change fibers described in the present invention; in the figure, the incident bands from top to bottom are: 7.23-9.63 μm (300-400K), 3.20-7.23 μm (400-900K), 2.22-3.20 μm (900-1200K);

[0034] Figure 2 Schematic diagram of the phase change fiber structure described in the present invention; Figure 2 Middle: 1 is the core material of the phase change fiber (dull phase change fiber), 2 is the shell material of the phase change fiber.

[0035] Figure 3 Schematic diagram of the phase change process and extinction mechanism of the extinction phase change fiber described in the present invention;

[0036] Figure 4 The effect of doping with extinction phase change fibers in three bands on the radiative thermal conductivity of aerogels at high temperatures; (a) is Mg / Si@SiO2; (b) is Zn / Al@SiO2; (c) is VO2@SiO2;

[0037] Figure 5 The graphs show the change of thermal conductivity of aerogels due to phase change fiber doping at different doping ratios at high temperature; (a) is Mg / Si@SiO2; (b) is Zn / Al@SiO2; (c) is VO2@SiO2;

[0038] Figure 6 Temperature rise curve of aerogel affected by phase change fiber doping at high temperature.

[0039] Figure 7 This is a graph showing the temperature rise curve of aerogel under vacuum and non-vacuum conditions. DETAILED DESCRIPTION

[0040] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0041] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0042] The present invention is further described in detail below in conjunction with the accompanying drawings:

[0043] The present invention proposes a band-controlled infrared phase change fiber doped aerogel, comprising an aerogel material, a phase change fiber with a reinforced structure, and the extinction phase change fiber is doped in multiple bands. That is, the present invention is a band-controlled infrared phase change fiber doped aerogel, wherein the doping basis is: the temperature gradient of the thermal insulation material, the phase change temperature and latent heat of the phase change material, the incident light band and the extinction performance of the phase change material.

[0044] The present invention adopts Al2O3 aerogel as a high temperature resistant filling material, and arranges three doping layers of phase change fiber in the aerogel from the short wave band to the long wave band (high temperature end to low temperature end) layer by layer according to the incident wave band, and the core material types of the extinction phase change fiber in different doping layers are all different.

[0045] The doped aerogel material has multiple layers of phase change fiber doping. Figure 1 As shown, the phase change fiber is doped layer by layer from the short wavelength band to the long wavelength band. The phase change temperature, phase change latent heat and volume fraction of the phase change fiber gradually decrease from the first doping layer.

[0046] Each doping layer can be prepared by any method for preparing a fiber-phase change material encapsulation-aerogel composite material disclosed in the prior art. Herein, one of the preparation methods is listed, including the following steps:

[0047] 1) Preparation of aluminum oxide precursor solution: dissolve an aluminum oxide source (such as aluminum chloride, aluminum nitrate, etc.) in a suitable amount of solvent, add alcohol amine as a catalyst, stir evenly, and obtain an aluminum oxide precursor solution.

[0048] 2) Preparation of phase change fibers: The materials are prepared into phase change fibers by melt spinning or other methods.

[0049] 3) Mixing the precursor solution and the phase change fiber: Add the prepared phase change fiber to the alumina precursor solution in a certain proportion, and ensure that the phase change fiber is evenly dispersed by mechanical stirring, ultrasonic dispersion and other means.

[0050] 4) Gelation process: Pour the mixed solution into a mold and gel at room temperature or slightly above room temperature to form a wet gel.

[0051] 5) Solvent exchange and aging: The wet gel is subjected to solvent exchange, replacing the original solvent with a non-reactive solvent, and subjected to aging treatment to enhance the gel structure.

[0052] 6) Supercritical drying or atmospheric pressure drying: The aged gel is subjected to supercritical drying to remove the solvent in the gel to obtain dry alumina aerogel-doped phase change fibers.

[0053] 7) Heat treatment: The dried alumina aerogel-doped phase change fiber is heat treated to enhance its mechanical properties and thermal stability.

[0054] Example:

[0055] In this embodiment, an infrared spectrum control aerogel vacuum insulation board doped with extinction phase change fiber is prepared. The core material is Al2O3 aerogel doped with three layers of extinction phase change fiber. The density of pure Al2O3 aerogel material is 120kg / m 3 , from short-wave band to long-wave band, each layer is doped with 5% magnesium-silicon alloy, 4% zinc-aluminum alloy and 2% vanadium dioxide phase change fiber (optimal doping ratio). The shell is made of SiO2, a single material that is resistant to high temperatures and has a certain light-shielding effect. The outer diameter is 4μm and the inner and outer diameter ratio is 0.95.

[0056] Material application conditions: high temperature side is 1300K, low temperature side is 300K, insulation on all sides, thickness of insulation material is 6mm.

[0057] Figure 4 In order to simulate the experiment and verify the effect of the extinction phase change fiber doping in three bands on the radiative thermal conductivity of aerogel at high temperature in the above embodiment, Figure 4 The three figures in the figure respectively illustrate the radiative thermal conductivity (λ r ) changes, the material shows a lower λ after phase transition rThe extinction performance of magnesium-silicon alloy before, after and at the optimal arrangement angle. It can be seen from the figure that magnesium-silicon alloy phase change fiber has good extinction properties before phase change. When phase change occurs, the radiation thermal conductivity is further reduced, and the alloy phase change improves the extinction performance.

[0058] Figure 5 The figure shows the change of thermal conductivity of aerogel under different doping ratios of phase change fiber at high temperature. The horizontal axis in the figure is the doping ratio, which shows the change of thermal conductivity under different doping ratios. It can be seen that when the doping ratio is small, its thermal conductivity is dominated by radiation thermal conductivity. The greater the doping amount of phase change fiber, the stronger the effect of its extinction performance and the lower the radiation thermal conductivity. When the optimal doping ratio is exceeded, the effect of radiation gradually decreases, and due to the continuous increase in the doping amount, the proportion of solid phase thermal conductivity becomes larger and larger, and solid phase heat transfer becomes the main heat transfer method.

[0059] Figure 6 This is a graph showing the temperature rise curve of aerogels doped with phase change fibers at high temperatures. Taking magnesium-silicon alloy as an example, due to the poor heat capacity of pure Al2O3 aerogel, the temperature of pure Al2O3 aerogel rises sharply at T=900K~1300K and quickly reaches a steady state. After doping with magnesium-silicon alloy phase change fibers, the infrared shielding film formed by the metal alloy weakens the radiation heat transfer, so it is insensitive to temperature response. Compared with pure aerogel, the transient temperature rise rate is delayed by 69.54%, which means that the response time to temperature is significantly prolonged. At the same time, the presence of phase change latent heat can further delay short-term heat transfer. Infrared phase change fiber doped aerogel with sub-band regulation can minimize radiation heat transfer and improve short-term heat transfer characteristics, maximizing the engineering application of the thermal insulation performance of Al2O3 aerogel.

[0060] Figure 7 This is the temperature rise curve of the three aerogels under vacuum and non-vacuum conditions. The transient temperature rise time is delayed compared to the original undoped state, and the time constant increases to about 3.23, 1.52 and 5.98 times the original. It can be seen that when in a non-vacuum state, the gas molecules are constantly moving and colliding at high speed. When a part of the gas is heated, the gas molecules therein will gain more energy, increase their speed, and intensify the convective heat transfer, thereby causing the thermal insulation performance of the material to deteriorate. On the contrary, when the material is in a vacuum state, there is no convective heat transfer, and the total heat transfer coefficient of the material decreases, resulting in an increase in the time constant.

[0061] In summary, the present invention provides an infrared extinction aerogel vacuum insulation board using phase change fibers doped in different bands. This material has low thermal conductivity, good short-term thermal insulation properties and the characteristics of inhibiting radiative heat transfer, avoiding a series of problems caused by the collapse of traditional silica aerogels and the cracking of sunscreens, improving the temperature control ability of the thermal protection system within a limited thickness, and spectrally regulating the doping of phase change fibers according to the incident band to meet the long-term thermal insulation requirements in different bands, and optimizing the doping ratio to further meet the short-term thermal insulation needs of aerospace and other industries.

[0062] The innovation of the present invention is that Al2O3 aerogel has better mechanical properties in high temperature environment and its structure is not easy to collapse, so it is more suitable for high temperature conditions than SiO2 aerogel. Radiative heat transfer increases significantly under high temperature. The high light transmittance of aerogel at 3 to 8 μm greatly weakens the thermal insulation performance. The present invention only dopes the aerogel with extinction phase change fiber, which can enhance the structure, replace the sunscreen, avoid the difficulty of later maintenance caused by the rupture of the sunscreen, and inhibit radiative heat transfer under high temperature. The extinction performance of the phase change fiber before phase change is better than that of traditional SiO2 and TiO2 fibers. The change of internal microstructure after phase change causes further improvement of the extinction performance, and significantly improves the effect of inhibiting radiative heat transfer. Based on the mechanism of improving extinction performance after phase change, the three phase change fibers are spectrally regulated and gradient doped according to the incident wavelength to maximize the engineering application of the thermal insulation performance of aerogel. Doping phase change material into aerogel significantly improves the heat storage capacity of aerogel, improves the thermal inertia of the material, and improves the high-temperature short-term thermal insulation performance of the material within a limited thickness. Phase change fibers are evenly distributed in different bands inside the aerogel material. In addition to the core material of the fiber absorbing heat and deglazing, the shell material can also play a certain deglazing role. The phase change material is encapsulated inside the high temperature resistant fiber shell to effectively avoid the damage to the matrix structure after the phase change material melts, and prevent the deterioration of thermal insulation performance.

[0063] Therefore, the phase change fiber in the present invention has better extinction performance than traditional SiO2 and TiO2 fibers; the extinction performance of the phase change fiber is further improved after the phase change; based on the extinction performance improvement mechanism, the phase change fiber is modulated and doped in different bands to maximize the engineering application of the thermal insulation performance of the aerogel; compared with the doping of sunscreen agents, the structure can be enhanced to effectively avoid a series of problems caused by the easy rupture of sunscreen agents in high-pressure applications; compared with the doping of single phase change materials, it has better phase change temperature control function.

[0064] The above contents are only for explaining the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. An infrared spectrum control aerogel vacuum insulation panel doped with extinction phase change fiber, characterized in that: It includes an aerogel core material and a vacuum packaging shell layer covering the outside of the aerogel core material, wherein the vacuum packaging shell layer seals the aerogel core material in a near-vacuum environment; The aerogel core material is composed of Al2O3 aerogel doped with at least three layers of extinction phase change fibers, and the doped extinction phase change fibers account for 10% to 15% of the volume of the Al2O3 aerogel; The vacuum packaging shell material is selected from a material that is resistant to high temperatures and has a matte property.

2. The infrared spectrum control aerogel vacuum insulation panel doped with extinction phase change fiber according to claim 1, characterized in that: The extinction phase change fiber includes semiconductor oxides, organic phase change materials or metal alloys.

3. The infrared spectrum control aerogel vacuum insulation panel doped with extinction phase change fiber according to claim 1, characterized in that: At least three layers of doped extinction phase change fibers are arranged layer by layer from a short-wave band to a long-wave band according to a temperature concentration peak.

4. The infrared spectrum control aerogel vacuum insulation panel doped with extinction phase change fiber according to claim 3, characterized in that: The bands are divided into the following according to the peak concentration section: Short wave band: 2.22~3.20μm, 900~1300K; Medium band: 3.20~7.23μm, 400~900K; Long wave band: 7.23~9.63μm, 300~400K.

5. The infrared spectrum controllable aerogel vacuum insulation panel doped with extinction phase change fiber according to any one of claim 4, characterized in that: The phase change temperature, latent heat, volume fraction and extinction performance parameters of the extinction phase change fibers doped in the short-wave, medium-wave and long-wave bands are set to high, moderate and low respectively; the doping volume fractions of the extinction phase change fibers doped in the short-wave, medium-wave and long-wave bands decrease in turn.

6. The infrared spectrum controllable aerogel vacuum insulation panel doped with extinction phase change fiber according to any one of claim 4, characterized in that: In the infrared spectrum range of 2.22-3.20 μm, the phase transition temperature is 1219 K and the latent heat is 757 kJ·kg -1 The magnesium-silicon alloy is used in the infrared spectrum range of 3.20-7.23 μm with a phase transition temperature of 710 K and a latent heat of 117 kJ·kg -1 The zinc-aluminum alloy is used in the infrared spectrum range of 7.23-9.63μm with a phase transition temperature of 341K and a latent heat of 43kJ·kg -1 VO2.

7. The infrared spectrum control aerogel vacuum insulation panel doped with extinction phase change fiber according to claim 4, characterized in that: At least three layers of extinct phase change fibers are arranged at a specific angle of 70°.

8. The infrared spectrum control aerogel vacuum insulation panel doped with extinction phase change fiber according to any one of claims 1 to 7, characterized in that: The outer diameter of the extinction phase change fiber is 4-6 μm, and the ratio of the inner diameter to the outer diameter of the extinction phase change fiber is 0.

95.

9. The infrared spectrum control aerogel vacuum insulation panel doped with extinction phase change fiber according to any one of claims 1 to 7, characterized in that: The vacuum packaging shell material is selected from SiC, TiO2 or SiO2.

10. Application of the infrared spectrum controllable aerogel vacuum insulation panel doped with extinction phase change fiber as claimed in any one of claims 1 to 9 in aerospace thermal protection systems.

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