Satellite heat dissipation system based on graphite composite phase change heat expansion plate

Abstract

The invention belongs to the technical field of spacecrafts, and particularly relates to a satellite heat dissipation system based on a graphite composite phase change heat expansion plate, which comprises a high-thermal-conductivity graphite composite phase change heat expansion plate, a short-time high-heat-consumption single machine, a satellite aluminum honeycomb plate and a heat dissipation window, the short-time high-heat-consumption single machine is fixedly installed in the middle of the upper surface of the high-heat-conduction graphite composite phase change heat expansion plate, the high-heat-conduction graphite composite phase change heat expansion plate is fixedly installed on the satellite aluminum honeycomb plate, and a heat dissipation window is formed in the middle of the face, attached to the high-heat-conduction graphite composite phase change heat expansion plate, of the satellite aluminum honeycomb plate. The high-thermal-conductivity graphite composite phase change heat expansion plate has the function of expanding the heat dissipation area of a single machine, and the peak temperature of the single machine during short-time high-heat-consumption working can be effectively reduced; and the phase-change material in the high-thermal-conductivity graphite composite phase-change heat expansion plate can absorb a large amount of heat generated when the single machine is started up, the phase-change latent heat is utilized, the heating rate and the peak temperature when the single machine is started up are remarkably reduced, and the single machine is prevented from being damaged due to short-time high heat.

Description

Technical Field

[0001] This invention belongs to the field of spacecraft technology, specifically relating to a satellite heat dissipation system based on a graphite composite phase change heat spreader. Background Technology

[0002] With the continuous development of satellite space missions, spacecraft mission modes are becoming increasingly diverse, the overall power consumption of the satellite is continuously increasing, and the integration of individual units is constantly improving. The short-term peak power consumption of high heat-consuming units is significantly increased, resulting in extremely high local heat flux density when the unit is working, making heat dissipation requirements increasingly urgent.

[0003] To ensure the long-term stable and reliable operation of individual units, their operating temperature must be maintained within a specific range. Therefore, effective measures must be taken to dissipate the heat generated during operation. For units with low power consumption on the satellite, temperature control can be achieved through measures such as surface spraying with a high emissivity coating and thermally conductive mounting with the mounting plate. However, for units with high heat consumption on the satellite, the conventional method is to use heat spreaders to diffuse heat and then conduct the heat away through high-efficiency heat transfer elements. However, as the short-term peak power consumption of high-heat-consumption units continues to rise, the required radiative heat dissipation area and heat spreader size also increase, which significantly increases the weight of the thermal control system. At the same time, when the unit is not in operation, the large aluminum alloy heat spreader and heat dissipation surface will experience serious heat leakage, requiring more electrical resources for temperature compensation. Due to the constraints of satellite launch costs, satellite weight and energy resources are extremely scarce, and the high weight and electrical resource requirements of conventional aluminum alloy heat spreaders make them unsuitable for current application needs.

[0004] Among existing related technologies, Chinese patent CN107167774A discloses a thermal control system for a dual-side-view high-power, high-heat-flux planar phased array antenna. This system includes a transmit / receive chip assembly and a phase-change heat pipe installed in the pre-embedded area of ​​a phase-change heat pipe in a structural honeycomb panel. The phase-change heat pipe is an aluminum-ammonia phase-change heat pipe, which plays a role in equalizing temperature and suppressing temperature rise in the transmit / receive chip assembly. Thermally conductive filler is provided between the transmit / receive chip assembly and the pre-embedded heat pipe area of ​​the honeycomb panel to increase contact heat conduction. This patent mainly employs traditional thermal control measures such as phase-change heat pipes. Chinese patent CN107995825A discloses a lightweight heat dissipation system for a high-heat-dissipation satellite unit based on heat pipes. This system includes a heat sink, a high-heat-dissipation unit, and pre-embedded heat pipes. The high-heat-dissipation unit is installed on the inner surface of the heat sink, and three pre-embedded heat pipes are located within the heat sink. This patent mainly uses a heat pipe network to dissipate heat from the high-power unit. Chinese patent CN103079381A discloses a satellite... Phase change heat pipes for satellite payloads and instrument panels include rectangular aluminum profiles with a heat pipe hole in the center area having an Ω-shaped axial channel core. At least two axial phase change holes are distributed on each side of the heat pipe hole. After phase change material is injected into the phase change holes, they are sealed to form a phase change material chamber. This patent mainly focuses on the design of phase change heat pipes, adding sealed chambers to both sides of ordinary aluminum ammonia heat pipes and filling them with paraffin wax. Chinese patent with publication number CN108831837A discloses a method for preparing a high thermal conductivity phase change temperature control composite packaging substrate, which directly integrates a low melting point alloy solid phase change material into an LTCC-AIN composite substrate to form a phase change temperature control device with high integration and high thermal conductivity. This patent mainly fills the substrate where electronic components are mounted with metal phase change material. Chinese patent with publication number CN108997978A discloses a solid composite phase change heat storage material and its preparation method. The material includes microporous polypropylene particles and composite phase change material. The composite phase change material is mainly a crystalline salt or an alcohol.

[0005] In summary, existing thermal control measures are insufficient to meet the heat dissipation requirements of short-term high-heat-consumption single-unit applications, and there is an urgent need for a thermal control system that can enhance the heat dissipation capacity of short-term high-heat-consumption single-unit applications. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the purpose of this invention is to provide a satellite heat dissipation system based on a graphite composite phase change heat expansion plate, which achieves coordinated heat dissipation through "heat expansion-heat storage-direct radiation" and effectively reduces the peak temperature and heating rate of a single unit while controlling system weight and energy consumption.

[0007] According to the present invention, a satellite heat dissipation system based on a graphite composite phase change heat expansion plate includes a high thermal conductivity graphite composite phase change heat expansion plate, a short-time high heat consumption unit, a satellite aluminum honeycomb panel, and a heat dissipation window.

[0008] The short-time high heat consumption single unit is fixedly installed on the middle of the upper surface of the high thermal conductivity graphite composite phase change heat expansion plate. The high thermal conductivity graphite composite phase change heat expansion plate is fixedly installed on the satellite aluminum honeycomb plate. A heat dissipation window is opened in the middle of the contact surface between the satellite aluminum honeycomb plate and the high thermal conductivity graphite composite phase change heat expansion plate. The high thermal conductivity graphite composite phase change heat expansion plate is formed by combining an upper cover plate, a graphite composite phase change material, and a lower cover plate. The ratio of the phase change energy storage to the mass of the high thermal conductivity graphite composite phase change heat expansion plate is ≥90kJ / kg.

[0009] Preferably, it also includes a thermal control component, which includes an electric heater that is fitted and installed on the outer surface of the housing of the short-term high-heat-consumption unit.

[0010] Preferably, the mounting screws of the short-time high-heat-consumption unit pass through the high thermal conductivity graphite composite phase change heat expansion plate and are threadedly connected and fixed to the satellite aluminum honeycomb panel.

[0011] Preferably, the edge of the high thermal conductivity graphite composite phase change heat expansion plate is uniformly provided with screw mounting holes along the circumferential direction, and the high thermal conductivity graphite composite phase change heat expansion plate is fastened to the satellite aluminum honeycomb plate by screws passing through the mounting holes.

[0012] Preferably, the area inside the high thermal conductivity graphite composite phase change heat expansion plate corresponding to the short-time high heat consumption single-machine mounting screw, and the area corresponding to the six screw mounting holes on the edge, are all integrally formed with metal bosses; the metal bosses and the lower cover plate are an integral structure, and a through hole for screws to pass through is opened in the middle of the bosses.

[0013] Preferably, the outline size of the heat dissipation window is smaller than the outline size of the mounting surface of the short-term high heat consumption unit, and the edge of the heat dissipation window does not exceed the distribution range of the mounting screws of the short-term high heat consumption unit.

[0014] Preferably, the base material of the upper cover plate and the lower cover plate is 6063 aluminum alloy, and the thickness of the cover plate is 1mm; the inner wall of the lower cover plate is integrally processed with reinforcing ribs.

[0015] Preferably, the graphite composite phase change material is made with high thermal conductivity honeycomb worm graphite as the skeleton and filled with hexadecane; the graphite composite phase change material is solid at room temperature and is cut to a suitable shape according to the internal cavity size of the high thermal conductivity graphite composite phase change heat expansion plate before filling.

[0016] Preferably, the upper cover plate and the lower cover plate are sealed together by welding to form a closed cavity to accommodate the graphite composite phase change material.

[0017] Preferably, the outer surface of the high thermal conductivity graphite composite phase change heat expansion plate is coated with S781 white paint, and the outer surface of the short-time high heat consumption unit is coated with E51-M black paint.

[0018] Compared with the prior art, the present invention has the following beneficial effects: 1. The high thermal conductivity graphite composite phase change heat expansion plate used in this invention has the function of expanding the heat dissipation area of ​​a single unit, which can effectively reduce the peak temperature of a single unit during short-term high heat consumption operation, and solve the problem of low heat dissipation efficiency caused by insufficient heat dissipation area of ​​traditional heat expansion plates; moreover, the phase change material in the high thermal conductivity graphite composite phase change heat expansion plate can absorb a large amount of heat generated when the single unit is turned on, and utilize the latent heat of phase change to significantly reduce the heating rate and peak temperature of the single unit when it is turned on, thus avoiding damage to the single unit due to short-term high heat.

[0019] 2. This invention uses a window opening method on the satellite compartment for direct heat dissipation, allowing the high thermal conductivity graphite composite phase change heat expansion plate to directly exchange heat with the cold background of space. Compared with the traditional indirect heat dissipation method, the heat dissipation efficiency is higher and the waste heat generated by the unit can be dissipated more effectively.

[0020] 3. This invention adopts mature aluminum alloy welding and graphite filling processes, and the components are compatible with the existing satellite assembly process; the structural design of metal bosses, reinforcing ribs and other components improves the vibration and impact resistance, and meets the requirements of satellite launch and on-orbit working environment. Attached Figure Description

[0021] 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 schematic diagram of the structure of the present invention; Figure 2 This is a schematic diagram of the satellite aluminum honeycomb panel and heat dissipation window of the present invention; Figure 3 This is a schematic diagram of the structure of the high thermal conductivity graphite composite phase change heat spreader of the present invention.

[0022] The following are the labeling elements in the figure: 1. Satellite aluminum honeycomb panel; 2. Heat dissipation window; 3. High thermal conductivity graphite composite phase change heat expansion plate; 4. Short-time high heat consumption single unit; 5. Top cover plate; 6. Graphite composite phase change material; 7. Bottom cover plate. Detailed Implementation

[0023] 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.

[0024] like Figure 1As shown, this embodiment provides a satellite heat dissipation system based on a graphite composite phase change heat expansion plate, including a high thermal conductivity graphite composite phase change heat expansion plate 3, a short-time high heat consumption unit 4, a satellite aluminum honeycomb panel 1, and a heat dissipation window 2.

[0025] The surface of the short-time high heat consumption unit 4 is sprayed with E51-M black paint to improve its heat absorption performance. The short-time high heat consumption unit 4 is fixedly installed in the middle of the upper surface of the high thermal conductivity graphite composite phase change heat spreader plate 3. RKTL-DRZ-1 thermally conductive silicone grease is filled between the short-time high heat consumption unit 4 and the high thermal conductivity graphite composite phase change heat spreader plate 3 to reduce the contact thermal resistance between them and ensure efficient heat transfer. The high thermal conductivity graphite composite phase change heat spreader plate 3 is fixedly installed on the satellite aluminum honeycomb panel 1. The contact surface between the high thermal conductivity graphite composite phase change heat spreader plate 3 and the satellite aluminum honeycomb panel 1 is filled with GDA-508 thermally conductive silicone rubber to further optimize heat conduction. Thermal effect: The high thermal conductivity graphite composite phase change heat spreader plate 3 is fixed to the satellite aluminum honeycomb panel 1 by titanium alloy screws; in this embodiment, the mounting screws of the short-term high heat consumption unit 4 pass through the composite phase change heat spreader plate 3 and are threaded to the satellite aluminum honeycomb panel 1. The composite phase change heat spreader plate 3 has 6 mounting holes around its edge. The composite phase change heat spreader plate 3 has an integrated metal boss with the lower shell inside the mounting hole position of the unit. A through hole is opened at the center of the boss to facilitate screw installation and enhance the structural stability and thermal conductivity of the mounting part; the outer side of the high thermal conductivity graphite composite phase change heat spreader plate 3 is sprayed with S781 white paint thermal control coating to enhance the radiative heat dissipation capacity.

[0026] This embodiment also includes a thermal control component, which includes an electric heater that is fitted and installed on the housing of the short-term high heat consumption unit 4 for temperature compensation during non-operation periods.

[0027] like Figure 2 As shown, a heat dissipation window 2 is provided in the middle of the bonding surface between the satellite aluminum honeycomb panel 1 and the high thermal conductivity graphite composite phase change heat expansion plate 3. The outline size of the heat dissipation window 2 is smaller than the mounting surface size of the short-term high-power single unit 4, and cannot exceed the position of the mounting screws of the short-term high heat consumption single unit 4 to avoid affecting the installation stability. In this embodiment, the mounting surface size of the short-term high heat consumption single unit 4 is 350mm×200mm, and the size of the heat dissipation window 2 is 280mm×150mm. Through the heat dissipation window 2, the high thermal conductivity graphite composite phase change heat expansion plate 3 can directly exchange heat with the cold background of space, which greatly improves the heat dissipation efficiency of the system.

[0028] like Figure 3As shown, the ratio of phase change energy storage to mass of the high thermal conductivity graphite composite phase change heat expansion plate 3 is ≥90kJ / kg. The high thermal conductivity graphite composite phase change heat expansion plate 3 includes an upper cover plate 5, a high thermal conductivity graphite composite phase change material 6, and a lower cover plate 7. The upper cover plate 5 and the lower cover plate 7 form a shell. The upper cover plate 5 and the lower cover plate 7 are made of 6063 aluminum alloy with a thickness of 1mm, which effectively controls the overall weight while ensuring structural strength and thermal conductivity. The inner wall of the lower cover plate 7 is integrally processed with reinforcing ribs to improve structural strength. Between the upper cover plate 5 and the lower cover plate 7... The plate is filled with a high thermal conductivity graphite composite phase change material 6, which is composed of a high thermal conductivity graphite honeycomb mesh structure and a paraffin-based phase change working fluid, and has excellent latent heat of phase change. In this embodiment, the graphite composite phase change material 6 is made by filling hexadecane with a high thermal conductivity honeycomb worm graphite skeleton. It is solid at room temperature and is filled after being cut according to the internal cavity size of the composite phase change heat expansion plate 3. The upper cover plate 5 and the lower cover plate 7 are sealed by welding to prevent leakage of the internal phase change material and ensure the sealing and reliability of the composite phase change heat expansion plate.

[0029] The heat dissipation effect of the heat dissipation system in this embodiment on the satellite was simulated and analyzed under the following conditions: The satellite's orbital period is 90 minutes (60 minutes during the illumination period and 30 minutes during the shadow period). The single unit 4, which experiences short-term high heat consumption, outputs 240W of power during the first 45 minutes of the illumination period and does not operate during the rest of the time.

[0030] Through thermal analysis software and ground simulation tests, the temperature of the single unit after on-orbit balancing is between 16.2℃ and 25.1℃, which meets the temperature requirements of a typical satellite unit from -10℃ to 45℃, fully demonstrating the effectiveness and reliability of the heat dissipation system of this invention.

[0031] 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.

[0032] 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 satellite heat dissipation system based on a graphite composite phase change heat spreader, characterized in that, It includes a high thermal conductivity graphite composite phase change heat expansion plate (3), a short-time high heat consumption single unit (4), a satellite aluminum honeycomb panel (1) and a heat dissipation window (2); The short-term high heat consumption unit (4) is fixedly installed on the middle of the upper surface of the high thermal conductivity graphite composite phase change heat expansion plate (3). The high thermal conductivity graphite composite phase change heat expansion plate (3) is fixedly installed on the satellite aluminum honeycomb plate (1). A heat dissipation window (2) is opened in the middle of the contact surface between the satellite aluminum honeycomb plate (1) and the high thermal conductivity graphite composite phase change heat expansion plate (3). The high thermal conductivity graphite composite phase change heat expansion plate (3) is formed by combining an upper cover plate (5), a graphite composite phase change material (6) and a lower cover plate (7). The ratio of the phase change energy storage to the mass of the high thermal conductivity graphite composite phase change heat expansion plate (3) is ≥90kJ / kg.

2. The satellite heat dissipation system based on a graphite composite phase change heat spreader according to claim 1, characterized in that, It also includes a thermal control component, which includes an electric heater that is fitted to the outer surface of the housing of the short-term high heat consumption unit (4).

3. The satellite heat dissipation system based on a graphite composite phase change heat spreader according to claim 1, characterized in that, The mounting screws of the short-time high heat consumption unit (4) pass through the high thermal conductivity graphite composite phase change heat expansion plate (3) and are threadedly connected and fixed to the satellite aluminum honeycomb plate (1).

4. The satellite heat dissipation system based on a graphite composite phase change heat spreader according to claim 1, characterized in that, The edge of the high thermal conductivity graphite composite phase change heat expansion plate (3) is uniformly provided with 6 screw mounting holes along the circumference. The high thermal conductivity graphite composite phase change heat expansion plate (3) is fastened to the satellite aluminum honeycomb plate (1) by screws passing through the mounting holes.

5. The satellite heat dissipation system based on a graphite composite phase change heat spreader according to claim 1, characterized in that, The area inside the high thermal conductivity graphite composite phase change heat expansion plate (3) corresponding to the mounting screws of the short-time high heat consumption unit (4) and the area corresponding to the 6 screw mounting holes on the edge are all integrally formed with metal bosses; the metal bosses and the lower cover plate (7) are an integral structure, and a through hole for screws to pass through is opened in the middle of the bosses.

6. The satellite heat dissipation system based on a graphite composite phase change heat spreader according to claim 1, characterized in that, The outline size of the heat dissipation window (2) is smaller than the outline size of the mounting surface of the short-term high heat consumption unit (4), and the edge of the heat dissipation window (2) does not exceed the distribution range of the mounting screws of the short-term high heat consumption unit (4).

7. The satellite heat dissipation system based on a graphite composite phase change heat spreader according to claim 1, characterized in that, The base material of the upper cover plate (5) and the lower cover plate (7) is 6063 aluminum alloy, and the thickness of the cover plate is 1mm; the inner wall of the lower cover plate (7) is integrally processed with reinforcing ribs.

8. The satellite heat dissipation system based on a graphite composite phase change heat spreader according to claim 1, characterized in that, The graphite composite phase change material (6) is made with high thermal conductivity honeycomb worm graphite as the skeleton and filled with hexadecane. The graphite composite phase change material (6) is solid at room temperature and is filled after being cut to fit the internal cavity size of the high thermal conductivity graphite composite phase change heat expansion plate (3).

9. The satellite heat dissipation system based on a graphite composite phase change heat spreader according to claim 1, characterized in that, The upper cover plate (5) and the lower cover plate (7) are sealed together by welding to form a closed cavity to accommodate the graphite composite phase change material (6).

10. The satellite heat dissipation system based on a graphite composite phase change heat spreader according to claim 1, characterized in that, The outer surface of the high thermal conductivity graphite composite phase change heat expansion plate (3) is coated with S781 white paint, and the outer surface of the short-time high heat consumption single machine (4) is coated with E51-M black paint.

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