Intelligent thermal control coating and applications thereof

Abstract

The application relates to the field of spacecraft thermal control technology, in particular to an intelligent thermal control coating and application thereof. The intelligent thermal control coating comprises a non-space-facing surface connected with a base body and a space-facing surface connected with the non-space-facing surface, the space-facing surface is connected with an open space; the space-facing surface is a transparent surface layer; the non-space-facing surface is a phase change heat conducting material layer, the phase change heat conducting material layer comprises a base body and a plurality of cavities in the base body, and a phase change material is arranged in the cavities. The intelligent thermal control coating is designed based on a glass type secondary surface mirror, the thermal control coating has high radiation heat dissipation capacity and good temperature stability, has the characteristics of simple process, high reliability and wide engineering application range in the field of spaceflight, and effectively avoids the disadvantages of additional energy consumption or limited function compared with traditional intelligent thermal control coatings.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of spacecraft thermal control technology, in particular, to an intelligent thermal control coating and application thereof. BACKGROUND

[0002] Due to the high vacuum environment of the space, the heat exchange between the spacecraft and the external environment is mainly by radiation. In the field of space, the thermal optical properties such as the thermal radiation performance of the material surface are usually used to achieve the purpose of temperature control. For spacecraft, all external surfaces are thermal control coating materials. According to the space environment characteristics of the spacecraft, the suitable thermal control coating is selected, which is a common means to control the heat exchange between the inside and outside of the spacecraft.

[0003] For the external surface of the spacecraft, the space thermal environment includes solar radiation, earth albedo, and earth infrared radiation heat flow. Therefore, when selecting the thermal control coating for the external surface of the spacecraft, the two most important performance parameters, solar absorption ratio and infrared emissivity, should be concerned. The former determines the absorption amount of the spacecraft external surface to the solar radiation, which is the main space heat flow. The latter determines the absorption amount of the spacecraft external surface to the earth infrared radiation heat flow and the ability to radiate heat to the space environment. Accordingly, according to the use performance, the thermal control coating on the spacecraft is classified into high emissivity thermal control coating, low emissivity thermal control coating, and low absorption high emissivity thermal control coating.

[0004] When selecting the thermal control coating for the external surface of the spacecraft, the heat dissipation requirement of the equipment carried thereon is considered, and the low absorption high emissivity thermal control coating is usually selected, such as thermal control white paint and secondary surface mirror. The surface thermal optical properties of such materials are relatively stable. Although they have excellent heat dissipation characteristics, the severe temperature fluctuations caused by the complex and changeable space environment also require a large amount of electric heating power for temperature compensation when the temperature is low. Exploring intelligent coatings with strong self-adaptability in high temperature and low temperature environments has always been the key breakthrough direction of the development of spacecraft thermal control technology.

[0005] Figure 1 The glass type secondary surface mirror shown is in a traditional form; in the figure, the transparent surface layer 1 has strong absorption to infrared rays and has high infrared emissivity. Quartz glass or cerium-doped quartz glass is usually used as the surface layer. The surface is the space-facing side. The metal thin layer 2 is attached to the transparent surface layer 1 and has a low solar absorption ratio. Aluminum or silver and other materials are usually used. The surface is the side that is attached to the spacecraft structure.

[0006] The currently widely known intelligent coating is divided into three categories: micro-shutter, electrochromic active thermal control coating and emissivity adjustable coating caused by thermochromic effect. Among them, the micro-shutter thermal control coating has high processing difficulty, the electrochromic active thermal control coating needs to consume energy and occupies the scarce circuit control channel resources on the spacecraft, and the emissivity adjustable coating caused by thermochromic effect has the advantages of high reliability and strong adaptability to large-scale production, but also has the disadvantage that the adjustable range of emissivity is very limited.

[0007] Therefore, the present application is proposed. SUMMARY

[0008] In order to solve the problem that the spacecraft thermal control coating cannot have both high radiation heat dissipation ability and good temperature stability, the present application provides an intelligent thermal control coating and its application. The coating has the characteristics of strong reliability and wide engineering application range in the field of spaceflight, and effectively avoids the disadvantages of additional energy consumption or limited function compared with the traditional intelligent thermal control coating.

[0009] In order to achieve the above-mentioned purpose of the present application, the following technical scheme is adopted:

[0010] In one aspect of the present application, an intelligent thermal control coating is provided, which comprises a non-space-facing surface connected with a base and a space-facing surface connected with the non-space-facing surface, and the space-facing surface is connected with an open space.

[0011] The space-facing surface is a transparent surface layer.

[0012] The non-space-facing surface is a phase change heat conducting material layer, which comprises a base and a plurality of cavities in the base, and a phase change material is arranged in the cavities.

[0013] The intelligent thermal control coating is designed based on a glass type secondary surface mirror, and has both high radiation heat dissipation ability and good temperature stability. The coating also has the characteristics of simple process, high reliability and wide engineering application range in the field of spaceflight, and effectively avoids the disadvantages of additional energy consumption or limited function compared with the traditional intelligent thermal control coating.

[0014] Another aspect of the present application also relates to the application of the intelligent thermal control coating in the preparation of a spacecraft.

[0015] Another aspect of the present application also relates to a spacecraft, which comprises a spacecraft body and the intelligent thermal control coating arranged on the outer surface of the spacecraft body, and the non-space-facing surface of the intelligent thermal control coating is connected with the spacecraft body.

[0016] Compared with the prior art, the present application has the following advantages:

[0017] The intelligent thermal control coating provided by this invention has a phase change thermal conductive material layer composited on the non-space-facing surface of the secondary surface mirror. In terms of performance, it can ensure excellent heat dissipation characteristics, while avoiding the direct impact of changes in external space heat flow on the spacecraft, thereby reducing the severity of spacecraft temperature fluctuations. In terms of process implementation and engineering application, it not only has high reliability, but also has high adaptability to large-scale production and implementation. Attached Figure Description

[0018] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0019] Figure 1 A schematic diagram of a traditional glass-type secondary surface mirror;

[0020] Figure 2 This is a schematic diagram of the structure of the intelligent thermal control coating provided in an embodiment of the present invention.

[0021] Figure label:

[0022] 1-Transparent surface layer, 2-Thin metal layer, 3-Phase change thermal conductive material layer, 4-Cavity, 5-Substrate. Detailed Implementation

[0023] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings and specific embodiments. However, those skilled in the art will understand that the embodiments described below are some embodiments of the present invention, but not all embodiments, and are only used to illustrate the present invention, and should not be regarded as limiting the scope of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall be followed. Where the manufacturers of reagents or instruments are not specified, they are all conventional products that can be purchased commercially.

[0024] One aspect of the present invention relates to a smart thermal control coating, such as Figure 2 As shown, the intelligent thermal control coating includes a non-space-facing surface connected to the substrate 5 and a space-facing surface connected to the non-space-facing surface, wherein the space-facing surface is connected to the open space;

[0025] The surface facing the space is a transparent layer;

[0026] The non-space-facing surface is a phase change heat conducting material layer, the phase change heat conducting material layer comprises a substrate 5 and a plurality of cavities 4 in the substrate 5, and a phase change material is arranged in the cavity 4.

[0027] The application provides a novel intelligent thermal control coating based on a glass type secondary surface mirror, which has high heat radiation and heat dissipation capacity and good temperature stability, and has the characteristics of simple process, high reliability and wide engineering application range in the field of spaceflight.

[0028] The intelligent thermal control coating is provided with a phase change heat conducting material layer 3 on the non-space-facing surface of the secondary surface mirror, which can guarantee excellent heat dissipation performance and avoid the direct influence of the change of external heat flow on the spacecraft, so as to reduce the intensity of temperature fluctuation of the spacecraft.

[0029] The design concept of the application is that the glass type secondary surface mirror is not directly used as a thermal control coating of a spacecraft, but is directly used as a thermal control coating material of a phase change sealing layer.

[0030] Further, the side surface of the phase change heat conducting material layer 3 in contact with the transparent surface layer 1 is a polished metal surface.

[0031] The polished metal layer is used to replace the metal film of the secondary surface mirror in the traditional form on the side surface of the phase change heat conducting material layer 3 in contact with the transparent surface layer 1, and the other side is attached to the spacecraft structure.

[0032] The polished metal process is used on the contact surface of the phase change heat conducting material layer 3 and the transparent surface layer 1, so that the polished metal surface has low solar absorption ratio and strong reflection of sunlight under the premise of ensuring that the surface has low solar absorption ratio.

[0033] Further, the thickness of the transparent surface layer 1 is 0.1-0.2 mm, including but not limited to any one of 0.1 mm, 0.12 mm, 0.14 mm, 0.16 mm, 0.18 mm or 0.2 mm or a range value between any two of them.

[0034] Further, the thickness of the phase change heat conductive material layer 3 is 1.5-2.5 mm, including but not limited to any one of 1.5 mm, 1.7 mm, 1.9 mm, 2.1 mm, 2.3 mm or 2.5 mm, or a range value between any two of them. If the thickness of the phase change heat conductive material layer 3 is too thin, it is difficult to ensure the structural strength of the phase change heat conductive material layer 3 and the filling amount of the phase change material, and if it is too thick, it will increase the temperature difference between the coating radiation heat dissipation surface and the spacecraft surface, and also increase the weight of the coating per unit area.

[0035] Further, the volume ratio of the phase change material to the cavity 4 is 0.8-0.9:1, including but not limited to 0.8:1, 0.82:1, 0.84:1, 0.86:1, 0.88:1 or 0.9:1. Considering the volume change of the phase change material when the phase state changes, the volume ratio of the phase change material to the cavity is limited within a certain range.

[0036] Further, the depth of the cavity 4 is 0.5-1.5 mm, including but not limited to any one of 0.5 mm, 0.7 mm, 0.9 mm, 1.1 mm, 1.3 mm or 1.5 mm, or a range value between any two of them.

[0037] The thickness of each material layer is limited within a certain range, which can ensure that the coating has high radiation heat dissipation capacity and good temperature stability.

[0038] The depth of the cavity 4 mentioned in the present application refers to the height of the cavity 4 from the space-facing surface to the non-space-facing surface.

[0039] Further, the material of the transparent surface layer 1 includes glass.

[0040] Further, the material of the transparent surface layer 1 includes quartz glass.

[0041] Further, the material of the transparent surface layer 1 includes quartz glass containing rare earth elements; the rare earth elements include but are not limited to cerium.

[0042] Further, the material of the substrate 5 is a metal material with heat conduction capacity and forming capacity, and the thermal conductivity coefficient of the material of the substrate 5 is 120-400 W / m / k. The heat conductive metal material with a thermal conductivity coefficient within this range and a certain forming capacity can be used to implement the technical solutions of the present application.

[0043] Further, the material of the substrate 5 includes but is not limited to at least one of aluminum, silver, gold, copper or aluminum alloy.

[0044] The phase change heat conducting material layer 3 and the cavity 4 are processed in an integrated manner, the cavity 4 has a small depth, the phase change material has poor thermal conductivity, and the small depth of the cavity 4 is beneficial to the complete phase change latent heat effect of the material distributed along the longitudinal direction of the cavity 4, so as to reduce the longitudinal temperature difference, and meanwhile, the small depth of the cavity 4 is simple to process and has a mature processing technology.

[0045] The melting point of the phase change material can be selected according to the mission characteristics and temperature requirements of the spacecraft, and the design and implementation method of the present application has strong adaptability and universality, and can be mass-produced as a component unit.

[0046] Further, the melting point of the phase change material is 0-20℃, including but not limited to any one of 0℃, 3℃, 5℃, 8℃, 10℃, 13℃, 15℃, 18℃ or 20℃, or a range value between any two of them. 0-20℃ is the ideal temperature control range of the spacecraft structure plate.

[0047] Further, the phase change material in the present application has a phase change temperature of 0-20℃, which can be used to implement the present application. In some specific embodiments, the phase change material includes but is not limited to pentadecane and / or hexadecane.

[0048] The phase change material encapsulated in the cavity 4 plays a role in flattening the temperature fluctuation peak of the spacecraft and maintaining the internal temperature of the spacecraft stable, according to the overall temperature maintenance level requirement of the spacecraft.

[0049] The phase change material can be encapsulated in a solid state, and the manufacturing process is simple.

[0050] In some specific embodiments, the phase change material is pentadecane (phase change point temperature is 10℃) as an example, and the working state of the intelligent thermal control coating is described as follows:

[0051] 1. When the internal temperature of the spacecraft exceeds 10℃, the phase change material absorbs the heat of the spacecraft and undergoes a phase change process from solid to liquid, and under the auxiliary action of the base 5, the heat is transferred to the polished surface of the phase change heat conducting material layer 3 and the transparent surface layer 1, so as to dissipate heat to space, and in this process, the phase change material has high phase change latent heat capacity, and its existence does not negatively affect the heat dissipation of the spacecraft;

[0052] 2. When the external solar radiation heat flux of the spacecraft is large, the heat flow reaches the polished surface of the phase change heat conducting material layer 3 and the transparent surface layer 1, causing the temperature to rise, and due to the high phase change latent heat characteristics of the phase change material, the heat disturbance does not directly cause temperature fluctuation on the surface of the spacecraft, thereby playing a role in flattening the temperature fluctuation peak of the spacecraft to a certain extent.

[0053] Another aspect of the present application also relates to the use of the intelligent thermal control coating in the preparation of a spacecraft.

[0054] Further, the intelligent thermal control coating is used to prepare the outer surface of the spacecraft.

[0055] Another aspect of the present application also relates to a spacecraft, comprising a spacecraft body and the intelligent thermal control coating arranged on the outer surface of the spacecraft body; the non-space-facing surface of the intelligent thermal control coating is connected with the spacecraft body.

[0056] The space-facing surface refers to the part or surface of an object or structure that is directly exposed to the external space (such as outside the atmosphere). For example, in the design of a spacecraft, a specific part of its outer shell is usually designed to face the space to withstand extreme environmental conditions such as vacuum, extreme temperature, cosmic rays, etc.

[0057] The open space refers to the external environment in which the space-facing surface is located.

[0058] The embodiments of the present application will be described in detail below with reference to the examples, but those skilled in the art will understand that the following examples are only used to illustrate the present application and should not be regarded as limiting the scope of the present application. The specific conditions not specified in the examples are carried out according to the conventional conditions or the conditions recommended by the manufacturer. The reagents or instruments used are not specified by the manufacturer, which are conventional products that can be obtained by purchase.

[0059] Example 1

[0060] The intelligent thermal control coating provided in this example comprises a non-space-facing surface connected with a substrate 5 and a space-facing surface connected with the non-space-facing surface, and the space-facing surface is connected with the open space;

[0061] The space-facing surface is a transparent surface layer;

[0062] The non-space-facing surface is a phase change heat conducting material layer, which comprises a substrate 5 and a plurality of cavities 4 in the substrate 5, and a phase change material is arranged in the cavities 4;

[0063] The side surface of the phase change heat conducting material layer 3 in contact with the transparent surface layer 1 is a polished metal surface;

[0064] The thickness of the transparent surface layer 1 is 0.15 nm; the thickness of the phase change heat conducting material layer 3 is 2 mm; the volume ratio of the phase change material to the cavity 4 is 0.85:1; and the depth of the cavity 4 is 1 mm;

[0065] The material of the transparent surface layer 1 is quartz glass; the material of the cavity 4 is aluminum; and the phase change material is n-pentadecane.

[0066] Example 2

[0067] The intelligent thermal control coating provided in the embodiment comprises a non-space-facing surface connected with the base 5 and a space-facing surface connected with the non-space-facing surface, and the space-facing surface is connected with an open space;

[0068] The space-facing surface is a transparent surface layer;

[0069] The non-space-facing surface is a phase change heat conducting material layer, and the phase change heat conducting material layer comprises the base 5 and a plurality of cavities 4 in the base 5, and a phase change material is arranged in the cavities 4;

[0070] The side surface of the phase change heat conducting material layer 3 in contact with the transparent surface layer 1 is a polished metal surface;

[0071] The thickness of the transparent surface layer 1 is 0.13 mm; the thickness of the phase change heat conducting material layer 3 is 1.8 mm; the volume ratio of the phase change material to the cavity 4 is 0.87:1; and the depth of the cavity 4 is 1.3 mm;

[0072] The material of the transparent surface layer 1 is cerium-containing quartz glass; the material of the cavity 4 is silver; and the phase change material is n-hexadecane.

[0073] Embodiment 3

[0074] The intelligent thermal control coating provided in the embodiment comprises a non-space-facing surface connected with the base 5 and a space-facing surface connected with the non-space-facing surface, and the space-facing surface is connected with an open space;

[0075] The space-facing surface is a transparent surface layer;

[0076] The non-space-facing surface is a phase change heat conducting material layer, and the phase change heat conducting material layer comprises the base 5 and a plurality of cavities 4 in the base 5, and a phase change material is arranged in the cavities 4;

[0077] The side surface of the phase change heat conducting material layer 3 in contact with the transparent surface layer 1 is a polished metal surface;

[0078] The thickness of the transparent surface layer 1 is 0.1 mm; the thickness of the phase change heat conducting material layer 3 is 1.5 mm; the volume ratio of the phase change material to the cavity 4 is 0.8:1; and the depth of the cavity 4 is 0.5 mm;

[0079] The material of the transparent surface layer 1 is quartz glass; the material of the cavity 4 is silver; and the phase change material is n-hexadecane.

[0080] Embodiment 4

[0081] The intelligent thermal control coating provided in the embodiment comprises a non-space-facing surface connected with the base 5 and a space-facing surface connected with the non-space-facing surface, and the space-facing surface is connected with an open space;

[0082] The space-facing surface is a transparent surface layer;

[0083] The non-spatially-oriented surface is a phase change heat conducting material layer, which comprises a base 5 and a plurality of cavities 4 in the base 5, and a phase change material is arranged in the cavities 4;

[0084] The side surface of the phase change heat conducting material layer 3, which is in contact with the transparent surface layer 1, is a polished metal surface;

[0085] The thickness of the transparent surface layer 1 is 0.2 mm; the thickness of the phase change heat conducting material layer 3 is 2.5 mm; the volume ratio of the phase change material to the cavities 4 is 0.9:1; and the depth of the cavities 4 is 1.5 mm;

[0086] The material of the transparent surface layer 1 is cerium-containing quartz glass; the material of the cavities 4 is aluminum; and the phase change material is n-pentadecane.

[0087] Embodiment 5

[0088] The spacecraft provided in the embodiment is provided with the intelligent thermal control coating provided in Embodiment 1 on its outer surface.

[0089] Embodiment 6

[0090] The spacecraft provided in the embodiment is provided with the intelligent thermal control coating provided in Embodiment 2 on its outer surface.

[0091] Embodiment 7

[0092] The spacecraft provided in the embodiment is provided with the intelligent thermal control coating provided in Embodiment 3 on its outer surface.

[0093] Embodiment 8

[0094] The spacecraft provided in the embodiment is provided with the intelligent thermal control coating provided in Embodiment 4 on its outer surface.

[0095] Although the present application has been illustrated and described with respect to specific embodiments, it is realized that the above embodiments are only used to illustrate the technical solutions of the present application, and are not used to limit the present application; it is understood by those skilled in the art that the technical solutions recorded in the above embodiments can be modified, or some or all of the technical features can be replaced equivalently, without departing from the spirit and scope of the present application; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application; therefore, this means that all the replacements and modifications within the scope of the present application are included in the appended claims.

Claims

1. An intelligent thermal control coating, characterized in that, The intelligent thermal control coating comprises a non-space-facing surface connected with a base and a space-facing surface connected with the non-space-facing surface, and the space-facing surface is connected with an open space; The space-facing surface is a transparent surface layer; The non-space-facing surface is a phase change heat conducting material layer, which comprises a base and cavities in the base, and the cavities are filled with phase change materials; The side surface of the phase change heat conducting material layer, which is in contact with the transparent surface layer, is a polished metal surface.

2. The intelligent thermal control coating of claim 1, wherein, The thickness of the transparent surface layer is 0.1-0.2 mm; And / or, the thickness of the phase change heat conducting material layer is 1.5-2.5 mm.

3. The intelligent thermal control coating of claim 1, wherein, At least one of the following technical features is included: (1) The volume ratio of the phase change material to the cavities is 0.8-0.9:1; (2) The depth of the cavities is 0.5-1.5 mm.

4. The intelligent thermal control coating of claim 1, wherein, The material of the transparent surface layer comprises glass; And / or, the material of the base comprises heat conducting metal material.

5. The intelligent thermal control coating of claim 1, wherein, The melting point of the phase change material is 0-20℃.

6. The intelligent thermal control coating of claim 1, wherein, The phase change material comprises n-pentadecane and / or n-hexadecane.

7. Use of the intelligent thermal control coating according to any one of claims 1-6 in the preparation of a spacecraft.

8. Use according to claim 7, characterized in that, The intelligent thermal control coating is used in the preparation of the outer surface of the spacecraft.

9. A spacecraft, characterized by, The spacecraft comprises a spacecraft body and the intelligent thermal control coating according to any one of claims 1-6 arranged on the outer surface of the spacecraft body, and the non-space-facing surface of the intelligent thermal control coating is connected with the spacecraft body.

Images