Infrared spectrum regulation of aerogel vacuum insulation board by doping extinction phase change fiber and application thereof

Abstract

The application discloses an infrared spectrum regulation and control aerogel vacuum heat insulation plate using a waveband-doped extinction phase change fiber and application thereof, and belongs to the technical field of high-temperature heat protection of a spacecraft. The vacuum heat insulation plate comprises an aerogel core material and a vacuum packaging shell layer wrapped outside the aerogel core material, the vacuum packaging shell layer encloses the aerogel core material in an approximate vacuum environment, and the aerogel core material is composed of Al2O3 aerogel doped with at least three layers of extinction phase change fibers. The application solves the problems of low strength, high infrared light transmission and poor thermal inertia of the existing aerogel heat protection system by transforming the traditional solid fiber into the extinction phase change fiber. Meanwhile, the application effectively replaces the light shielding agent and avoids the problem caused by the breakage of the light shielding agent in actual aerospace application. The structural change caused by the phase change can improve the short-term heat insulation performance of the overall material and improve the extinction performance. On this basis, the spectrum regulation and control can maximize the engineering application of the heat insulation performance of the heat protection system.

Description

Technical Field

[0001] This invention belongs to the field of high-temperature thermal protection technology for spacecraft, specifically relating to an infrared spectral modulated aerogel vacuum insulation panel using wavelength-division doped extinction phase change fibers and its application. Background Technology

[0002] Vacuum insulation panels are a type of vacuum insulation material composed of a filler material and a vacuum layer. While meeting the same insulation requirements, they can achieve a thinner insulation layer, smaller volume, and lighter weight. Aerogel, as another ultra-strong insulation material, has been studied and has been encapsulated within vacuum insulation panels as a filler material to form a new type of vacuum insulation panel. However, from the perspective of actual 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 at high temperature and the structure will collapse, which limits its application in high temperature conditions; (2) Since aerogel is highly transparent to 3-8μm near-infrared radiation at high temperature, its radiative heat transfer increases significantly when used in high temperature environment; (3) Its own specific heat capacity is low, its temperature response is fast in unsteady heat transfer, its short-term thermal insulation performance is poor, and its thermal insulation capacity is insufficient; (4) There is a temperature gradient in aerogel, and different types of matting materials have different matting characteristics and temperature resistance, and there is a lack of effective doping methods; (5) Traditional doping methods only carry out multilayer doping according to the optimal size, while ignoring the corresponding optimal doping ratio, and the fact that the matting characteristics of the fiber are related to the incident infrared wavelength.

[0003] Of course, existing technologies are actively seeking solutions to the aforementioned defects. For example, to address the issue of SiO2 aerogel's tendency to collapse at high temperatures, Al2O3 aerogel, with its stronger mechanical properties, is used as a substitute. Another example is the use of light-blocking agents such as SiC, TiO2, or SiO2 to suppress near-infrared radiation, addressing near-infrared transmittance issues. However, in aerospace applications, the sudden increase in surface pressure causes these agents to rupture rapidly within seconds, allowing fibers to align at specific angles and replace them, effectively suppressing near-infrared heat transfer. Yet another approach addresses the poor short-term thermal insulation performance of aerogels by encapsulating and supporting fibers with a light-blocking material, then incorporating the phase change material into the aerogel matrix. However, traditional doping methods only consider multi-layer doping based on optimal dimensions, neglecting the optimal doping ratio and the relationship between fiber extinction characteristics and incident infrared wavelength.

[0004] Therefore, existing vacuum insulation panels still suffer from technical problems such as poor thermal insulation performance, radiative heat transfer, and uncontrollable short-term thermal insulation due to the easy collapse of traditional silica aerogel and the cracking of light-blocking agents. Summary of the Invention

[0005] To overcome the shortcomings of the prior art, the present invention aims to provide an infrared spectral modulated aerogel vacuum insulation panel doped with phase change fibers and its application, which solves the shortcomings of existing aerogel thermal protection vacuum insulation panels such as low strength, strong infrared light transmission and poor thermal inertia; at the same time, it effectively replaces the light-shielding agent, avoiding the technical problems of poor heat insulation performance, radiative heat transfer and uncontrollable short-term heat insulation caused by the cracking of the light-shielding agent in actual aerospace applications.

[0006] To achieve the above objectives, the present invention employs the following technical solution:

[0007] This invention discloses an infrared spectral modulated aerogel vacuum insulation panel doped with extinction phase change fibers, comprising an aerogel core material and a vacuum encapsulation shell covering the outside of it, wherein the vacuum encapsulation shell seals the aerogel core material in a near-vacuum environment.

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

[0009] The vacuum-sealed shell material is selected from materials that are resistant to high temperatures and have matting properties.

[0010] Preferably, the phase change fiber core material with extinction properties 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 properties, etc., are selected according to the actual wavelength and thermal insulation environment.

[0011] Preferably, at least three layers of 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, so as to suppress the internal infrared radiation of the insulation board when the temperature difference between the cold and hot surfaces is as high as 1000K.

[0012] More preferably, the bands are divided according to the peak concentration segment:

[0013] Shortwave band: 2.22–3.20 μm, 900–1300 K;

[0014] Mid-wave band: 3.20–7.23 μm, 400–900 K;

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

[0016] Preferably, the phase transition temperature, latent heat, volume fraction, and extinction performance parameters of the extinction phase change fibers doped in the short-wavelength, medium-wavelength, and long-wavelength bands are set to high, moderate, and low, respectively; the doping volume fraction of the extinction phase change fibers doped in the short-wavelength, medium-wavelength, and long-wavelength bands decreases sequentially.

[0017] More preferably, infrared radiation is concentrated in phase change fiber A doped at 2.22–3.20 μm, where A must meet the characteristics of high phase change temperature, high latent heat, high volume fraction, and excellent extinction performance; phase change fiber B doped at 3.20–7.23 μm must meet the characteristics of moderate phase change temperature, moderate latent heat, moderate volume fraction, and moderate extinction performance; and phase change fiber C doped at 7.23–9.63 μm must meet the characteristics of low phase change temperature, low latent heat, and low volume fraction.

[0018] More preferably, the phase change temperature, latent heat, extinction characteristics, and other physical properties of the phase change core material of each layer of phase change fiber are determined by the actual incident wavelength of that layer. When the incident wavelength 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 alloys, can be selected. When the incident wavelength is between 3.20 and 7.23 μm (400 to 900 K), organic phase change materials with moderate phase change temperature and moderate latent heat, such as zinc-aluminum alloys, can be selected. When the incident wavelength 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, the phase transition temperature is 1219 K and the latent heat is 757 kJ·kg in the 2.22–3.20 μm infrared spectral range. -1 Magnesium-silicon alloy; with a phase transition temperature of 710 K and a latent heat of 117 kJ·kg⁻¹ in the 3.20–7.23 μm infrared spectral range. -1 Zinc-aluminum alloy; with a phase transition temperature of 341 K and a latent heat of 43 kJ·kg⁻¹ in the 7.23–9.63 μm infrared spectral range. -1 VO2.

[0020] More preferably, the doping volume fraction of the phase change fiber decreases from the short-wavelength band to the long-wavelength 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 selectively suppress infrared radiation in different wavelength bands based on different infrared radiation and the extinction performance enhancement mechanism after material phase change. The extinction performance of phase change fibers at a specific angle is superior to that of randomly doped traditional solid fibers, and it can more effectively suppress radiative heat transfer and improve the high-temperature thermal insulation performance of aerogel composites. The internal core material absorbs heat at a constant temperature during the phase change process, delays transient heat transfer, and improves the thermal inertia of the aerogel. Furthermore, after the core material undergoes phase change, it can further enhance the extinction characteristics of the material in a specific infrared band, matching the infrared spectral characteristics after temperature rise.

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

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

[0024] Furthermore, the inner-outer diameter ratio of the extinction phase change fiber is 0.95, which prevents core material leakage, ensures 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 properties, such as high-temperature resistant materials like SiC, TiO2, and SiO2.

[0026] Therefore, the shell material of the "phase change fiber" of this invention is a high-temperature resistant material with extinction properties, while the core is a solid-liquid phase change material whose extinction performance is improved after phase change and which can absorb heat at a constant temperature, thus overcoming the disadvantage of aerogels having a sharp increase in infrared radiation transmittance at high temperatures. This material, while having a low equivalent thermal conductivity, can also improve the poor thermal inertia of aerogels. It can not only optimize the short-term thermal insulation performance of aircraft thermal protection systems through the isothermal heat absorption of phase change fibers, but also further improve extinction performance after phase change, improving the temperature control capability of thermal protection systems within a limited thickness.

[0027] This invention also discloses the application of the infrared spectral modulated aerogel vacuum insulation board doped with extinction phase change fibers in aerospace thermal protection systems.

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

[0029] This invention discloses an infrared spectral modulated aerogel vacuum insulation panel doped with matting phase change fibers. Firstly, it uses Al2O3 aerogel, which has superior mechanical properties at high temperatures, instead of traditional SiO2 aerogel as the core filling material. Al2O3 aerogel exhibits better mechanical properties at high temperatures and is less prone to structural collapse, making it more suitable for high-temperature conditions than SiO2 aerogel. Simultaneously, a vacuum-sealed shell encloses the aerogel core in a near-vacuum environment, effectively preventing heat transfer caused by air convection between the insulation material and the filling material, thus significantly reducing the thermal conductivity. Secondly, the addition of matting phase change fibers to the aerogel core not only improves the material's mechanical properties but also replaces light-blocking agents, providing excellent performance. The matting effect effectively avoids a series of problems caused by the easy breakage of opaque agents in practical applications. The matting phase change fiber has better matting performance than traditional SiO2 and TiO2 fibers, and the matting performance is further improved after phase change. Furthermore, the vacuum encapsulation shell material is selected from high temperature resistant materials with matting properties, which work synergistically with the aerogel core material. Finally, the aerogel core material of this invention can also improve the problem of poor thermal inertia of aerogel when it has low equivalent thermal conductivity. It can not only optimize the short-term thermal insulation performance of the aircraft thermal protection system through the isothermal heat absorption of phase change fiber, but also further improve the matting performance after phase change, thereby improving the temperature control capability of the thermal protection system within a limited thickness. In summary, the vacuum insulation panel of this invention solves the shortcomings of existing aerogel thermal protection systems, such as low strength, high infrared transmittance, and poor thermal inertia, by transforming traditional solid fibers into matting phase change fibers. It also effectively replaces opaque agents, avoiding problems caused by their breakage in actual aerospace applications. The structural changes caused by the phase change improve both the short-term thermal insulation performance of the overall material and its matting properties. Furthermore, by utilizing spectral modulation, the thermal insulation performance of the thermal protection system can be maximized for engineering applications, demonstrating strong practicality.

[0030] Furthermore, this invention is based on the mechanism of improving the extinction performance and delaying transient heat transfer after the phase change of extinction phase change fibers. The spectral control is performed according to the wavelength to maximize the thermal insulation performance. The at least three layers of extinction phase change fibers are set from the short wavelength to the long wavelength according to the temperature concentration peak. The spectral control is performed in the aerogel matrix material according to the incident wavelength, which has better thermal insulation performance than traditional doped single-layer phase change materials.

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

[0032] Furthermore, the aerogel is doped with three or more layers of phase change fibers arranged at a specific 70° angle to selectively suppress infrared radiation in different wavelength bands based on different infrared radiation and the extinction performance enhancement mechanism after phase change. Experiments have shown that the extinction performance of phase change fibers at a specific angle is superior to that of randomly doped traditional solid fibers, and it can more effectively suppress radiative heat transfer and improve the high-temperature thermal insulation performance of aerogel composites. The internal core material absorbs heat at a constant temperature during phase change, delaying transient heat transfer and improving the thermal inertia of the aerogel. Moreover, after phase change, the core material can further enhance the extinction characteristics of the material in a specific infrared band, matching the infrared spectral characteristics after temperature rise. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the structure of an infrared matting aerogel vacuum insulation panel using wavelength-division doped phase change fibers as described in this invention; in the figure: the incident wavelengths from top to bottom are: 7.23~9.63μm (300~400K), 3.20~7.23μm (400~900K), 2.22~3.20μm (900~1200K);

[0034] Figure 2 The diagram below is a schematic diagram of the phase change fiber structure described in this invention; Figure 2 In the diagram: 1 represents the core material of the phase change fiber (dull phase change fiber), and 2 represents the shell material of the phase change fiber.

[0035] Figure 3 This is a schematic diagram illustrating the phase transition process and extinction mechanism of the extinction phase change fiber described in this invention;

[0036] Figure 4 The effect of extinction phase change fiber doping in three wavelength bands on the radiation thermal conductivity of aerogel at high temperature; where (a) is Mg / Si@SiO2; (b) is Zn / Al@SiO2; and (c) is VO2@SiO2.

[0037] Figure 5 The graph shows the change in thermal conductivity of aerogels under different doping ratios of phase change fibers at high temperatures; where (a) represents Mg / Si@SiO2; (b) represents Zn / Al@SiO2; and (c) represents VO2@SiO2.

[0038] Figure 6 The 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 curves of the aerogel under vacuum and non-vacuum conditions. Detailed Implementation

[0040] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort 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, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0042] The present invention will now be described in further detail with reference to the accompanying drawings:

[0043] This invention proposes a wavelength-controlled infrared phase change fiber-doped aerogel, comprising an aerogel material, a phase change fiber with a reinforcing structure, and an extinction phase change fiber doped in multiple wavelength bands. Specifically, this invention is a wavelength-controlled infrared phase change fiber-doped aerogel, wherein the doping is based on: the temperature gradient of the thermal insulation material, the phase change temperature and latent heat of the phase change material, the incident light wavelength band, and the extinction performance of the phase change material.

[0044] This invention uses Al2O3 aerogel as a high-temperature resistant filling material. The phase change fiber is set with three doped layers in the aerogel from the short wavelength band to the long wavelength band (from the high temperature end to the low temperature end) according to the incident wavelength band. The core material of the extinction phase change fiber with different doped layers is different.

[0045] Doped aerogel materials have multiple phase change fiber doped layers. For example... Figure 1 As shown, the phase change fiber is doped layer by layer from short-wavelength to long-wavelength. The phase change temperature, latent heat of phase change, and volume fraction gradually decrease starting from the first doped layer.

[0046] Each doped layer can be prepared using any existing fiber-phase change material encapsulation-aerogel composite material preparation method. One such method is described below, including the following steps:

[0047] 1) Preparation of alumina precursor solution: Dissolve the alumina source (such as aluminum chloride, aluminum nitrate, etc.) in an appropriate amount of solvent, add an alkanolamine as a catalyst, stir evenly to obtain the alumina precursor solution.

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

[0049] 3) Mixing the precursor solution with phase change fibers: The prepared phase change fibers are added to the alumina precursor solution in a certain proportion, and the phase change fibers are uniformly dispersed by means of mechanical stirring, ultrasonic dispersion and other methods.

[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 then aged 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 and obtain dried alumina aerogel-doped phase change fibers.

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

[0054] Example:

[0055] This embodiment prepares an infrared spectral modulated aerogel vacuum insulation panel doped with matting phase change fibers. The core material is a three-layer Al2O3 aerogel doped with matting phase change fibers. The density of pure Al2O3 aerogel material is 120 kg / m³. 3 Each layer, from short-wavelength to long-wavelength, 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 high-temperature resistant and light-shielding single material with an outer diameter of 4 μm and an inner-outer diameter ratio of 0.95.

[0056] Material application conditions: 1300K on the high-temperature side, 300K on the low-temperature side, with insulation on all four sides and a thickness of 6mm for the insulation material.

[0057] Figure 4 To simulate and verify the effect of extinction phase change fiber doping on the radiative thermal conductivity of aerogel in three wavelength bands at high temperature in the above embodiments, Figure 4 The three figures illustrate the radiative thermal conductivity (λ) of the three doped materials before and after the phase transition. r The material exhibits a lower λ after the phase transition, reflecting changes in its properties. rThe extinction properties of magnesium-silicon alloy before and after phase transformation and at the optimal arrangement angle are shown in the figure. It can be seen that the magnesium-silicon alloy phase transformation fiber has good extinction properties before phase transformation. When phase transformation occurs, the radiative thermal conductivity further decreases, and the alloy phase transformation improves the extinction performance.

[0058] Figure 5 This graph shows the change in thermal conductivity of aerogel under different doping ratios of phase change fibers at high temperatures. The horizontal axis represents the doping ratio, indicating the change in thermal conductivity at different doping ratios. It can be seen that when the doping ratio is small, the thermal conductivity is dominated by radiative thermal conductivity. The higher the doping amount of the phase change fiber, the stronger the extinction effect and the lower the radiative thermal conductivity. When the optimal doping ratio is exceeded, the effect of radiation gradually decreases, and due to the continuous increase in doping amount, the proportion of solid-phase thermal conductivity increases, making solid-phase heat transfer the main heat transfer mechanism.

[0059] Figure 6 This is a graph showing the temperature rise curve of aerogel 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, its temperature rises sharply and quickly reaches a steady state in the range of T = 900K to 1300K. After doping with magnesium-silicon alloy phase change fibers, the infrared shielding film formed by the metal alloy weakens radiative heat transfer, thus making it less sensitive to temperature response. Compared with pure aerogel, the transient temperature rise rate is slowed down by 69.54%, which means that the response time to temperature is significantly extended. At the same time, the presence of latent heat of phase change can further delay short-term heat transfer. Infrared phase change fiber doped aerogel with wavelength-controlled modulation can minimize radiative heat transfer and improve short-term heat transfer characteristics, maximizing the thermal insulation performance of Al2O3 aerogel for engineering applications.

[0060] Figure 7 This graph shows the temperature rise curves of three types of aerogels under vacuum and non-vacuum conditions. The transient heating time is slower than that of the undoped case, with the time constants increasing to approximately 3.23, 1.52, and 5.98 times the original values, respectively. It can be seen that in a non-vacuum state, gas molecules are constantly moving and colliding at high speeds. When some of the gas is heated, the gas molecules gain more energy, increasing their velocity and intensifying convective heat transfer, thus worsening the material's thermal insulation performance. Conversely, when the material is in a vacuum state, there is no convective heat transfer, the overall heat transfer coefficient of the material decreases, and the time constant increases.

[0061] In summary, this invention provides an infrared matting aerogel vacuum insulation panel utilizing wavelength-division doped phase change fibers. This material exhibits low thermal conductivity, excellent short-term insulation properties, and suppression of radiative heat transfer, avoiding the collapse of traditional silica aerogels and the problems caused by the cracking of opacifying agents. It improves the temperature control capability of thermal protection systems within a limited thickness. Furthermore, the spectral modulation of phase change fiber doping according to the incident wavelength meets the long-term insulation requirements of different wavelengths, and the optimized doping ratio further satisfies the short-term insulation needs of aerospace and other applications.

[0062] The innovation of this invention lies in the following: Al2O3 aerogel, due to its superior mechanical properties and less tendency to collapse in high-temperature environments, is more suitable for high-temperature conditions than SiO2 aerogel. At high temperatures, radiative heat transfer increases significantly, and the high light transmittance of aerogels (3–8 μm) greatly weakens their thermal insulation performance. This invention incorporates only matting phase change fibers into the aerogel, which strengthens the structure, replaces opaque agents, avoids the maintenance difficulties caused by opaque agent breakage, and suppresses radiative heat transfer at high temperatures. Before the phase change, the matting performance of the phase change fibers is superior to that of traditional SiO2 and TiO2 fibers. After the phase change, changes in the internal microstructure further enhance the matting performance, significantly improving the suppression of radiative heat transfer. Based on the mechanism of improved matting performance after the phase change, the three phase change fibers are spectrally controlled and gradient-doped according to the incident wavelength, maximizing the engineering application of the aerogel's thermal insulation performance. Incorporating phase change materials into the aerogel significantly improves its heat storage capacity, reduces the material's thermal inertia, and enhances the high-temperature short-term thermal insulation performance within a limited thickness. Phase change fibers are evenly distributed within the aerogel material in different wavelength bands. In addition to the core material of the fibers absorbing heat and extinct light, the shell material also plays a certain role in extinction. Encapsulating the phase change material inside a high-temperature resistant fiber shell effectively avoids damage to the matrix structure after the phase change material melts, thus preventing the thermal insulation performance from deteriorating.

[0063] Therefore, the phase change fiber in this invention has superior extinction properties compared to traditional SiO2 and TiO2 fibers; the extinction properties of the phase change fiber are further improved after phase change; based on the extinction performance enhancement mechanism, the phase change fiber is doped with waveband modulation to maximize the thermal insulation performance of the aerogel for engineering applications; compared with doping with opaque agents, it can enhance the structure and effectively avoid a series of problems caused by the easy cracking of opaque agents in high-pressure applications; compared with doping with a single phase change material, it has better phase change temperature control function.

[0064] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A vacuum insulation panel for infrared spectral modulation of aerogel doped with extinction phase change fibers, characterized in that, It includes an aerogel core material and a vacuum encapsulation shell covering the outside of it, which encloses the aerogel core material in a near-vacuum environment. The aerogel core material is composed of at least three layers of matting phase change fibers doped with Al2O3 aerogel, and the doped matting phase change fibers account for 10% to 15% of the volume of Al2O3 aerogel. 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. The bands are divided according to the peak concentration section: Short-wavelength band: 2.22–3.20 μm, 900–1300 K; in the 2.22–3.20 μm infrared spectral range, a phase transition temperature of 1219 K and a latent heat of 757 kJ·kg⁻¹ are used. -1 magnesium-silicon alloy; Mid-wave band: 3.20~7.23 μm, 400~900 K; in the 3.20~7.23 μm infrared spectral range, a phase transition temperature of 710 K and a latent heat of 117 kJ·kg⁻¹ are used. -1 Zinc-aluminum alloy; Long wavelength range: 7.23–9.63 μm, 300–400 K; In the 7.23–9.63 μm infrared spectral range, a phase transition temperature of 341 K and a latent heat of 43 kJ·kg⁻¹ are used. -1 VO2; The vacuum packaging shell material is selected from SiC, TiO2 or SiO2.

2. The infrared spectral modulated aerogel vacuum insulation panel with doped extinction phase change fibers according to claim 1, characterized in that, Extinction phase change fibers include semiconductor oxides, organic phase change materials, or metal alloys.

3. The infrared spectral modulated aerogel vacuum insulation panel doped with extinction phase change fibers according to claim 1, characterized in that, The phase transition temperature, latent heat, volume fraction, and extinction performance parameters of the extinction phase change fibers doped in the short-wavelength, medium-wavelength, and long-wavelength bands were set to high, moderate, and low, respectively; the doping volume fraction of the extinction phase change fibers doped in the short-wavelength, medium-wavelength, and long-wavelength bands decreased sequentially.

4. The infrared spectral modulated aerogel vacuum insulation panel doped with extinction phase change fibers according to claim 1, characterized in that, At least three layers of extinction phase change fibers are arranged at a specific 70° angle.

5. A vacuum insulation panel with infrared spectral modulation of doped extinction phase change fibers according to any one of claims 1 to 4, 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.

6. The application of the infrared spectral modulated aerogel vacuum insulation panel doped with extinction phase change fiber as described in any one of claims 1 to 5 in aerospace thermal protection systems.

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