Thermal control structure suitable for MEO microwave antenna

Abstract

The invention provides a thermal control structure suitable for an MEO microwave antenna, and belongs to the field of space thermal control. The MEO microwave antenna thermal control structure comprises an anti-radiation thermal control film, curing glue and a low-heat-conduction supporting column. The supporting column is installed on the surface of the microwave antenna waveguide through threads, and the anti-radiation thermal control film is attached to the top face of a cylindrical head of the supporting column through curing glue points. The thermal control film has low solar absorptivity and high hemispherical emissivity, the inner surface of the thermal control film performs radiation heat exchange with the waveguide, and the outer surface of the thermal control film performs radiation heat exchange with the space heat sink; the supporting columns are made of low-heat-conduction materials, heat conduction heat resistance from the waveguide to the thin film is increased, and heat leakage to a space heat sink is reduced. According to the invention, the compensation power consumption of the heater is remarkably reduced while the temperature of the antenna assembly meets the long-term working requirement in the MEO irradiation environment, and the space environment adaptability, the heat dissipation reliability and the wave-transparent performance are considered.

Description

Technical Field

[0001] This invention belongs to the field of space thermal control, specifically, it relates to a thermal control structure suitable for MEO microwave antennas, and more particularly to a high heat dissipation and low compensation thermal control structure suitable for MEO microwave antennas. Background Technology

[0002] Compared to previous low Earth orbit (LEO) and high Earth orbit (HEO) satellite antennas, medium Earth orbit (MEO) satellites operate in a new environment with harsh external heat flow and severe radiation. As satellite functions become more complex, the antenna area and heat dissipation increase significantly, and the antenna structure becomes increasingly complex. To reduce antenna weight, the internal hollow design greatly impacts the establishment of effective heat dissipation paths.

[0003] To ensure antenna efficiency, thermal control or heat treatment methods for antenna waveguide surfaces are becoming increasingly limited. Simultaneously, considering the overall satellite energy balance, the heater compensation power consumption during long-term continuous operation of large-array antennas is strictly limited. For satellite thermal control, the inability to perform secondary processing of the antenna waveguide surface and the risk of unwanted materials restrict the thermal control methods that can be used, such as painting or applying thermal control films. The hollow internal structure design means that traditional thermal control films cannot meet the heat dissipation requirements of high-heat-dissipation heat sources. The limitation of heater compensation power consumption requires the thermal control system to reduce energy demand through reasonable and innovative heat dissipation path design. To ensure that the antenna heat dissipation surface meets the reliability requirements of the MEO space environment, while having a low solar absorptivity, and effectively dissipating the heat generated during single-unit operation within the antenna to the space heat sink, while reducing energy consumption, a new high-heat-dissipation, low-compensation thermal control method suitable for the MEO space environment must be adopted.

[0004] Currently, few methods for thermal control of MEO microwave antennas have been disclosed. Existing technologies employ two conventional methods for high- and low-orbit microwave antennas: one is to cover the entire antenna waveguide surface with a germanium film, ensuring both antenna transmittance and heat dissipation requirements; the second is to perform bright anodizing on the array elements on the antenna waveguide surface, directly serving as a heat dissipation surface to maximize the antenna's electrical performance. Neither method can meet the reliability requirements of the heat dissipation surface under the harsh radiation environment of MEO. Furthermore, the high solar absorptivity cannot guarantee a good temperature level during long-term continuous antenna operation. To address these issues, it is necessary to research novel thermal control methods with high heat dissipation, radiation resistance, and low compensation characteristics.

[0005] Currently, the relevant existing technologies include:

[0006] A Chinese patent document with publication number CN103256841A discloses an energy storage and heat dissipation device. This device is a high-power heat dissipation device based on a foam material section, a loop heat pipe, a phase change material, and a radiation box. This method makes full use of the characteristics of the phase change material having a large latent heat of phase change and the loop heat pipe having high thermal conductivity, providing a solution for heat dissipation of aerospace electronic devices with high power density in a short time. However, this method uses a loop heat pipe and other components that are relatively large in volume and is mainly aimed at high-precision temperature control. It is not suitable for the thermal control of large-area microwave antenna components with limited space and weight resources.

[0007] Existing Chinese patent document CN106304778A discloses an integrated thermal control method for a high-heat-dissipation transient single-unit in space. Specifically, it is a heat dissipation method for high-heat-dissipation single-units based on phase change energy storage materials, which can reduce the peak temperature of the high-heat-dissipation single-unit, and the integrated design reduces heat transfer links. However, the phase change material proposed in this technical solution requires a packaged shell and a certain filling volume to achieve its function, resulting in a large overall size. It is suitable for large single units but not for antenna components with narrow installation space and small size.

[0008] A Chinese patent document with publication number CN111893451A discloses a high-performance transparent nanothermal control film for satellites, comprising a micro / nano structure system composed of a continuous phase and a discrete phase. The micro / nano structure system is prepared using a casting or melting method, and the micro / nano structures are distributed in an ordered hierarchical manner. This technical solution specifically discloses a thermal control film based on micro / nano structures, which has high wave transmittance and heat dissipation. However, if it is surface-mounted on the antenna surface, it will generate significant heater compensation power consumption, making it unsuitable for the heat dissipation surface of large-array antennas. Due to the high light transmittance of the nanofilm, if it is spot-mounted on the antenna surface, some sunlight will directly enter the antenna waveguide, resulting in a large temperature rise after prolonged continuous operation of the component, failing to meet heat dissipation requirements. Furthermore, the nanothermal control film lacks a specific design for adaptability to the MEO space environment.

[0009] Furthermore, the Chinese journal article "Environmental Adaptability Design and Verification of Spaceborne SAR Slotted Waveguide Antenna" (DOI: 10.12126 / see.2022106.) published by Wang Zhigang et al. in 2023, adopted a conventional surface electroplating bright anodized film for thermal control of microwave antennas. However, the orbital irradiance dose of this satellite is several orders of magnitude lower than that of MEO, which cannot meet the environmental adaptability requirements of MEO. High-energy charged particles can enter the waveguide cavity of the microwave antenna, and the internal components cannot meet the radiation resistance requirements. At the same time, the high solar absorptivity of the anodized film cannot meet the heat dissipation requirements of microwave antennas operating continuously for a long time. The Chinese journal article "Design and Verification of Thermal Control System for MEO Navigation Satellite" (DOI: 10.12126 / see.2022106.) published by Lin Shifeng et al. in 2022, adopted a heat pipe relay heat transfer thermal control measure for phased array antennas, utilizing the heat dissipation surface of the satellite for heat dissipation. However, this method is suitable for antennas with small area and low heat dissipation density. From the perspective of weight resources and space, it is not suitable for the thermal control of tens of thousands of components in large array antennas, and it lacks analysis of adaptability to the space environment. Summary of the Invention

[0010] To address the shortcomings of existing technologies, the purpose of this invention is to provide a thermal control structure suitable for MEO microwave antennas.

[0011] The thermal control structure for MEO microwave antennas provided by the present invention is characterized by comprising: an anti-radiation thermal control film, a curing adhesive, and a support column; The support columns are distributed and installed on the surface of the microwave antenna waveguide; The radiation-resistant thermal control film is bonded and fixed to the top surface of the support column by the curing adhesive; The inner surface of the radiation-resistant thermal control film forms a radiative heat transfer relationship with the surface of the microwave antenna waveguide, and the outer surface of the radiation-resistant thermal control film is used to radiate heat to the space heat sink.

[0012] Preferably, the support column is a cylindrical head slotted screw structure; The top surface of the cylindrical head is the bonding area for attaching the radiation-resistant thermal control film, and the slot is used to store a portion of the cured adhesive. The support column is made of a material with a thermal conductivity of less than 0.3 W / (mK).

[0013] Preferably, the support column is fixedly installed on the surface of the microwave antenna waveguide by means of a threaded connection.

[0014] Preferably, the radiation-resistant thermal control film is a double-layer composite structure, comprising: a radiation-resistant film substrate facing the microwave antenna waveguide and an outer radiation-resistant coating facing the external space.

[0015] Preferably, the curing adhesive is a thermally conductive adhesive pre-applied to the top surface of the support column, and its material is two-component silicone rubber.

[0016] Preferably, the material of the support column is polyimide.

[0017] Preferably, the radiation film substrate is a black polyimide film with a hemispherical emissivity of not less than 0.8, an average infrared transmittance of not more than 5%, and a thickness of not more than 250 micrometers.

[0018] Preferably, the outer radiation-resistant coating is an inorganic silicate material.

[0019] Preferably, the installation method for the thermal control structure of the MEO microwave antenna includes: Step S1: The working component is mechanically fixed to the lower surface of the antenna waveguide to establish a heat conduction path; Step S2: The support column is fixed to the upper surface of the antenna waveguide; Step S3: Apply the curing adhesive to the top surface of the cylindrical head of the support column to fill the slot; Step S4: With the inner layer of the radiation-resistant heat control film facing the support column, it is adhered to the upper surface of the cylindrical head of the support column using a curing adhesive.

[0020] A microwave antenna includes a thermal control structure suitable for MEO microwave antennas provided according to the present invention.

[0021] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention achieves the technical effect of efficient radiative heat dissipation of antennas and long-term tolerance to the harsh irradiation environment of MEO by using a high-performance anti-radiation thermal control film with low solar absorptivity, high hemispherical emissivity and resistance to environmental degradation. 2. This invention uses a support column made of a low thermal conductivity material and uses it as a thermal connection point between the thermal control film and the antenna waveguide, thereby introducing controllable thermal resistance in the heat dissipation path and reducing the heater compensation power consumption. 3. This invention designs the support column as a cylindrical head screw structure with a slotted groove and uses a pre-applied curing adhesive for spot installation, which ensures that the film is firmly adhered and has good thermal conductivity, while taking into account both process feasibility and connection reliability. 4. This invention constructs a multi-path heat dissipation channel: antenna waveguide → radiating / supporting column heat conduction → thermal control film → space heat sink. 5. This invention optimizes the thickness of the thermal control film and the infrared transmittance of the substrate, and controls the heat conduction of the support column, thereby achieving efficient thermal management without affecting the core wave transmission performance of the microwave antenna. Attached Figure Description

[0022] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 This is a cross-sectional schematic diagram of the thermal control structure of the present invention applicable to MEO microwave antennas; Figure 2 This is a schematic diagram showing the distribution of the support columns of the present invention on the surface of the microwave antenna waveguide; Figure 3 This is a schematic diagram of the radiation-resistant thermal control film structure of the present invention.

[0023] The diagram shows: Detailed Implementation

[0024] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the scope of protection of the present invention.

[0025] like Figure 1 As shown, this embodiment of the invention provides a thermal control structure suitable for MEO microwave antennas, and more particularly a high heat dissipation and low compensation thermal control structure suitable for MEO microwave antennas, comprising: an anti-radiation thermal control film 1, a curing adhesive 2, and a support column 3; The aforementioned support column 3 is mounted on the surface of the microwave antenna waveguide 4. The radiation-resistant thermal control film 1 is attached to the surface of the support column 3 by a curing adhesive 2. The microwave antenna waveguide 4 is connected to the working component 5. The working component 5 acts as a heat source, and the heat it generates is transferred to the microwave antenna waveguide 4. Part of the heat is radiated to the radiation-resistant thermal control film 1 through the microwave antenna waveguide, and the other part is transferred to the radiation-resistant thermal control film 1 through the support column 3 by thermal conduction. This ensures that the temperature of the working component 5 meets the requirements during the continuous long-term operation of the microwave antenna under MEO irradiation environment, while also having low heater compensation power consumption.

[0026] Furthermore, the aforementioned support column 3 is a low thermal conductivity support column, installed on the surface of the microwave antenna waveguide 4. There are multiple support columns 3, and they are uniformly distributed in the microwave antenna waveguide 4 as follows: Figure 2 As shown; The aforementioned support column 3 has a cylindrical head slotted screw, and the top surface of the cylindrical head of the support column 3 is the bonding area for the radiation-resistant film 1. Specifically, the radiation-resistant film 1 is bonded to the top surface of the cylindrical head of the support column 3 using a curing adhesive 2. The curing adhesive 2 is pre-coated on the top surface of the cylindrical head of the support column 3 as a thermally conductive filler to bond and fix the radiation-resistant thermal control film 1, ensuring good thermal conductivity between the support column 3 and the radiation-resistant thermal control film 1. The slotted groove of the support column 3 can, on the one hand, store the curing adhesive 2 and inhibit its flow, which is beneficial to the uniformity of bonding; on the other hand, the top surface of the cylindrical head of the support column 3 is the bonding area for the radiation-resistant film 1, and the grooved area... The small size maximizes the bonding area and flatness of the radiation-resistant thermal control film 1 while meeting installation process requirements; the support column 3 is made of low thermal conductivity materials, including but not limited to polyimide, with a thermal conductivity of less than 0.3 W / (mK), which can reduce the heat conduction between the microwave antenna waveguide and the high-performance radiation-resistant thermal control film 1, thereby reducing the heater compensation power consumption; more specifically, the support column 3 is installed on the surface of the microwave antenna waveguide 4 by means of threaded connection to ensure the firmness and reliability of the installation; the curing adhesive 2 is a two-component silicone rubber, and KH-CL-SP space-grade silicone rubber can be selected.

[0027] Furthermore, the aforementioned radiation-resistant thermal control film 1 is a high-performance radiation-resistant thermal control film with a low solar absorptivity and a high hemispherical emissivity, which can meet the adaptability requirements of the MEO space environment. The radiation-resistant thermal control film 1 and the microwave antenna waveguide 4 have two heat transfer methods: heat conduction and heat radiation. Specifically, the radiation-resistant thermal control film 1 conducts heat to the microwave antenna waveguide 4 through the support column 3, and the inner surface of the radiation-resistant thermal control film 1 directly radiates heat to the microwave antenna waveguide 4. In addition, the outer surface of the radiation-resistant thermal control film 1 radiates heat to the space heat sink, such as... Figure 3 As shown, the radiation-resistant thermal control film 1 is a multi-layer composite structure. In a specific embodiment, it is a double-layer composite structure, with the inner layer being a radiation-resistant film substrate 7 and the outer layer being a radiation-resistant coating 6. The surface of the inner radiation-resistant film substrate 7 faces the surface of the microwave antenna waveguide 4. Furthermore, in a more specific embodiment, the hemispherical emissivity of the radiation-resistant film substrate 7 of the aforementioned high-performance radiation-resistant film 1 is not less than 0.8, ensuring the radiative heat exchange performance with the microwave antenna waveguide surface; the average infrared transmittance of the radiation-resistant film substrate 7 is not greater than 5%, used to reduce the transmission of sunlight, and the specific material can be a black polyimide film; the thickness of the radiation-resistant film substrate 7 does not exceed 250 micrometers, ensuring that it does not affect the wave transmission performance when pasted on the microwave antenna waveguide surface. The main component of the radiation-resistant coating 6 of the aforementioned high-performance radiation-resistant film 1 is an inorganic material, which exhibits low degradation and stable performance under MEO irradiation environment, and can be silicate-based, without limitation. The aforementioned radiation-resistant film 1 exhibits no cracking, wrinkling, or failure in the MEO space environment. The radiation-resistant film substrate 7 radiates heat with the surface of the microwave antenna waveguide 4, and the radiation-resistant film substrate 7 conducts heat with the microwave antenna waveguide 4 through the support column 3, while the radiation-resistant coating 6 radiates heat with the space heat sink. The heat conduction and heat radiation of the thermal control structure of the present invention are as follows. Figure 1 As shown.

[0028] Furthermore, embodiments of the present invention also provide an installation method for a thermal control structure suitable for MEO microwave antennas, comprising: Step S1: The working component 5 is mechanically fixed to the lower surface of the antenna waveguide 4 to establish a good heat conduction path; Step S2: The support column 3 is fixed to the upper surface of the antenna waveguide 4 by means of a threaded connection; Step S3: Apply the curing adhesive 2 to the top surface of the cylindrical head of the support column 3 to fill the slot; Step S4: With the inner layer of the radiation-resistant heat control film 1 facing the support column 3, it is attached to the cylindrical head surface of the support column 3 using the curing adhesive 2.

[0029] In summary, this invention provides a high-heat-dissipation, low-compensation thermal control structure suitable for medium Earth orbit (MEO) microwave antennas. This structure meets the heat dissipation requirements of MEO microwave antennas operating continuously for extended periods under harsh radiation environments and energy constraints, while simultaneously reducing heater compensation power consumption. It involves a high-performance radiation-resistant thermal control film 1, a curing adhesive 2, and a low thermal conductivity support pillar 3. The high-performance radiation-resistant thermal control film 1 serves as the antenna heat dissipation surface and is spot-attached to the low thermal conductivity support pillar 3 via the curing adhesive 2. The low thermal conductivity support pillar 3 is mounted on the surface of the microwave antenna waveguide 4 for thermal resistance control. The radiation-resistant thermal control film 1 has a low solar absorptivity and a high hemispherical emissivity, meeting the heat dissipation requirements of MEO microwave antennas operating continuously for extended periods. Its inner surface directly radiates heat with the microwave antenna waveguide 4, while its outer surface radiates heat with the space heat sink, ensuring the reliability of the heat dissipation path design. This invention utilizes a high-performance radiation-resistant thermal control film 1 to reduce degradation under MEO irradiation, lowering solar absorptivity and transmittance, ensuring the antenna meets temperature requirements during long-term continuous operation. A low-thermal-conductivity support pillar 3 increases the thermal resistance between the antenna waveguide and the heat dissipation surface, reducing heat transfer between the antenna waveguide and the space heat sink, thereby reducing heater compensation power consumption. Simultaneously, the high emissivity of the low-thermal-conductivity support pillar 3 increases the radiative heat transfer path between the antenna waveguide and the heat dissipation surface. A curing adhesive 2 ensures the strong adhesion of the high-performance radiation-resistant thermal control film 1 to the surface of the low-thermal-conductivity support pillar 3 under MEO conditions, guaranteeing good thermal conductivity between the film and pillar 3, and improving the reliability of the antenna thermal control method. Therefore, this invention solves the problem of adaptability to the space environment for MEO microwave antenna thermal control, reduces heater compensation power consumption, and solves the problem of efficient heat dissipation of components after long-term continuous operation of the microwave antenna, ensuring the microwave antenna's wave transmission performance and operational reliability, achieving beneficial effects such as radiation resistance, low solar absorptivity, low transmittance, and low heater compensation.

[0030] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0031] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A thermal control structure suitable for MEO microwave antennas, characterized in that, include: Radiation-resistant thermal control film (1), curing adhesive (2), and support column (3); The support columns (3) are distributed and installed on the surface of the microwave antenna waveguide (4); The radiation-resistant thermal control film (1) is bonded and fixed to the top surface of the support column (3) by the curing adhesive (2); The inner surface of the radiation-resistant heat control film (1) forms a radiative heat transfer relationship with the surface of the microwave antenna waveguide (4), and the outer surface of the radiation-resistant heat control film (1) is used to radiate heat to the space heat sink.

2. The thermal control structure for MEO microwave antennas according to claim 1, characterized in that, The support column (3) is a cylindrical head slotted screw structure; The top surface of the cylindrical head is the bonding area for bonding the radiation-resistant heat control film (1), and the slot is used to store part of the cured adhesive (2). The support column (3) is made of a material with a thermal conductivity of less than 0.3 W / (mK).

3. The thermal control structure for MEO microwave antennas according to claim 1, characterized in that, The support column (3) is fixedly installed on the surface of the microwave antenna waveguide (4) by means of threaded connection.

4. The thermal control structure for MEO microwave antennas according to claim 1, characterized in that, The radiation-resistant thermal control film (1) is a double-layer composite structure, comprising: a radiation-resistant film substrate (7) facing the microwave antenna waveguide (4) and an outer radiation-resistant coating (6) facing the external space.

5. The thermal control structure for MEO microwave antennas according to claim 1, characterized in that, The curing adhesive (2) is a thermally conductive adhesive pre-coated on the top surface of the support column (3), and its material is two-component silicone rubber.

6. The thermal control structure for MEO microwave antennas according to claim 2, characterized in that, The material of the support column (3) is polyimide.

7. The thermal control structure for MEO microwave antennas according to claim 4, characterized in that, The radiation film substrate (7) is a black polyimide film with a hemispherical emissivity of not less than 0.8, an average infrared transmittance of not more than 5%, and a thickness of not more than 250 micrometers.

8. The thermal control structure for MEO microwave antennas according to claim 4, characterized in that, The outer radiation-resistant coating (6) is an inorganic silicate material.

9. The thermal control structure for MEO microwave antennas according to any one of claims 1 to 8, characterized in that, The installation method applicable to the thermal control structure of MEO microwave antennas includes: Step S1: The working component (5) is mechanically fixed to the lower surface of the antenna waveguide (4) to establish a heat conduction path; Step S2: The support column (3) is fixed to the upper surface of the antenna waveguide (4); Step S3: Apply the curing adhesive (2) to the top surface of the cylindrical head of the support column (3) to fill the groove; Step S4: The inner layer of the radiation-resistant thermal control film (1) faces the support column (3) and is pasted onto the cylindrical head surface of the support column (3) by the curing adhesive (2).

10. A microwave antenna, characterized in that, Includes a thermal control structure suitable for MEO microwave antennas as described in any one of claims 1 to 8.

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