A graphene membrane skin thermal control device

Abstract

The application relates to a graphene film skin heat control device, which comprises a graphene skin radiator and a paraffin thermal switch, the graphene skin radiator comprises a graphene core body and a polyimide film, the polyimide film is located on the outer layer of the graphene core body and encapsulates the graphene core body, the graphene skin radiator is connected with one side of the paraffin thermal switch, and the other side of the paraffin thermal switch is connected with an external heat source. The graphene film skin heat control device can realize rapid heat spreading for electronic equipment installed thereon, can realize efficient heat dissipation by using an external environment under high-temperature working conditions at a small resource cost, and can realize effective heat preservation of the electronic equipment under low-temperature working conditions.

Description

Technical Field

[0001] This invention relates to the field of thermal control devices for electronic devices, and more particularly to a thermal control device for graphene film skin. Background Technology

[0002] Avionics systems are a crucial component of modern aircraft, serving as a vital technological means to ensure mission objectives and safe flight, and a key factor determining the overall performance of modern aviation equipment. With the advancement of avionics technology, their power consumption and heat dissipation are continuously increasing, posing greater challenges to heat dissipation.

[0003] Cooling of electronic equipment mainly takes several forms, including active liquid cooling, active air cooling, and natural heat dissipation. Among these, active liquid cooling and air cooling have higher cooling efficiency and are more widely used. Active cooling can achieve good cooling effects, but the reliability of moving parts such as pumps and fans during long-term operation is a concern. On some aviation platforms, especially drones, airships, or small aircraft, due to resource and space constraints, active cooling resources cannot be provided for electronic equipment, and passive heat dissipation methods such as natural heat dissipation are used to solve the equipment's heat dissipation problem.

[0004] The external environment of an aircraft is characterized by low temperatures and high airflow. While a skin-type heat sink can utilize this low temperature to cool electronic equipment, traditional metal skin heat sinks still suffer from issues such as increased system weight and low heat dissipation efficiency. Therefore, a heat sink that can reduce system weight and increase heat dissipation efficiency is needed. Summary of the Invention

[0005] To address the existing technical problems, this invention provides a graphene film skin thermal control device. Through the flexible graphene composite film, conformal and structural-functional integrated design can be achieved. Combined with the design of a thermal switch, it utilizes the external environment to achieve efficient heat dissipation of electronic devices under high-temperature conditions and effective heat preservation under low-temperature conditions.

[0006] The specific content of the present invention is as follows: A graphene film-coated thermal control device includes a graphene film-coated heat sink and a paraffin thermal switch. The graphene film-coated heat sink includes a graphene core and a polyimide film. The polyimide film is located on the outer layer of the graphene core and is encapsulated thereon. The graphene film-coated heat sink is connected to one side of the paraffin thermal switch, and the other side of the paraffin thermal switch is connected to an external heat source.

[0007] Furthermore, the graphene core comprises one or more layers of graphene, a polyimide film is uniformly distributed on the outer surface of the graphene core and sealed at the edge of the graphene core, and the outer side of the polyimide film is metallized or coated with paint.

[0008] Furthermore, the paraffin thermal switch includes a thermal switch housing and paraffin wax. The thermal switch housing has a closed structure, and the paraffin wax is located inside the thermal switch housing. When the paraffin wax is in a solid state, a vacuum cavity is formed between the paraffin wax and the top of the thermal switch housing. When the paraffin wax is in a liquid state, it fills the entire thermal switch housing.

[0009] Furthermore, when the thermal control device is installed horizontally, the horizontal length of the paraffin thermal switch should not exceed the length of the graphene-skinned heat sink.

[0010] Furthermore, when the thermal control device is installed vertically, and the paraffin is in a solid state, the vertical length of the vacuum chamber is not less than the length of the graphene-coated heat sink.

[0011] Furthermore, the graphene skin heat sink is fixed to the heat source by adhesive bonding.

[0012] The beneficial effects of this invention are as follows: By using graphene as the internal heat-conducting core and high-strength encapsulation on the outer layer, a large-size composite graphene film with significant thickness, good thermal conductivity, and a certain structural strength can be obtained. For platforms such as low-speed drones and airships, the wind load on their skins is relatively low. The encapsulated and reinforced composite graphene film can meet the strength requirements of the skins of such platforms. The graphene skin heat sink is structurally fixedly connected to other skins of the platform, acting as the structural function of the skin. Its inner side is connected to the heat-generating electronic devices, achieving efficient heat dissipation to the environment after thermal expansion. A paraffin thermal switch is added between the electronic devices and the graphene skin heat sink. At low temperatures, the thermal switch is closed, blocking the heat transfer path between the electronic devices and the external environment; at high temperatures, the thermal switch is open, achieving effective heat exchange between the electronic devices and the external environment. The edges of the composite graphene film are connected and fixed to the structural skeleton or other skins, thereby maintaining the aerodynamic shape of the platform. Due to the flexibility of the graphene film, it can conform to the aerodynamic shape of the platform, achieving curved coverage. It can rapidly expand the thermal performance of electronic devices installed on it, and can achieve efficient heat dissipation by utilizing the external environment under high-temperature conditions with relatively low resource costs, and achieve effective heat preservation of electronic devices under low-temperature conditions. Attached Figure Description

[0013] The specific embodiments of the present invention will be further explained below with reference to the accompanying drawings.

[0014] Figure 1 This is a schematic diagram of the graphene film skin thermal control device of the present invention;

[0015] Figure 2 This is a schematic diagram of the graphene-coated heat sink structure of the present invention.

[0016] Figure 3 Schematic diagram of a paraffin thermal switch structure Figure 1 ;

[0017] Figure 4 Schematic diagram of a paraffin thermal switch structure Figure 2 ;

[0018] Figure 5 This is a schematic diagram illustrating the application of the graphene film skin thermal control device of the present invention. Figure 1 ;

[0019] Figure 6 This is a schematic diagram illustrating the application of the graphene film skin thermal control device of the present invention. Figure 2 .

[0020] Among them, 1. Graphene skin heat sink, 2. Heat source, 3. Paraffin thermal switch, 4. Graphene core, 5. Polyimide film, 6. High-gloss metallization layer, 7. Thermal switch shell, 8. Paraffin, 9. Vacuum cavity, 10. Wing structure skin. Detailed Implementation

[0021] Example 1

[0022] This embodiment provides a graphene film-covered thermal control device. The flexible graphene composite film can be conformally designed and, through the form of a skin heat sink, replaces the skin of drones or airships, achieving a structural and functional integration effect. Combined with the design of a thermal switch, it utilizes the external environment to achieve efficient heat dissipation of electronic devices under high-temperature conditions and effective heat preservation under low-temperature conditions. Furthermore, thanks to the high thermal conductivity of graphene, the system weight can be significantly reduced compared to traditional heat sinks.

[0023] Figure 1 This is a schematic diagram illustrating the working principle of a graphene film-covered thermal control device. The device includes a graphene film-covered heat sink 1 and a paraffin thermal switch 3. The graphene film-covered heat sink 1 comprises a graphene core 4 and a polyimide film 5. The polyimide film 5 is located on the outer layer of the graphene core 4 and encapsulates it. The graphene film-covered heat sink 1 is connected to one side of the paraffin thermal switch 3, and the other side of the paraffin thermal switch 3 is connected to an external heat source 2 (electronic equipment). The paraffin thermal switch 3 can switch between on and off states according to its own temperature. At high temperatures, the thermal switch is on, allowing the heat sink to expand the heat generated by the electronic device and dissipate heat to the external low-temperature environment through radiation and convection. At low temperatures, the thermal switch is off, reducing heat dissipation from the device to the environment and maintaining the device temperature.

[0024] Figure 2 This is a schematic diagram of a graphene-skinned heat sink. The graphene core 4 includes one or more layers of graphene. The polyimide film 5 is uniformly distributed on the outer surface of the graphene core 4 and is sealed at the edge of the graphene core 4. The outer side of the polyimide film 5 is metallized or coated with paint. In this embodiment, the outer side of the polyimide film 5 is a high-gloss metallized layer 6.

[0025] The graphene core 4 has a high thermal conductivity, playing a role in heat amplification and transfer. It is protected by an outer encapsulation layer of polyimide film 5. The skin heat sink is located on the outermost surface of the aircraft. Depending on its installation location, it is directly affected by solar radiation or Earth's infrared reflection. Therefore, the outer surface of the heat sink undergoes surface treatment. The polyimide encapsulation layer is treated with high-gloss metallization such as aluminum plating or coated with white paint, giving the surface high radiative and low radiative properties. This enhances the ability to radiate heat to the environment and reduces the impact of external solar radiation and Earth's reflection on heat dissipation, thereby improving heat dissipation efficiency.

[0026] Figure 5 This is a schematic diagram of the graphene film skin thermal control device structure installed on an aircraft wing. The graphene skin heat sink 1 replaces part of the wing structure skin 10, and is connected to the wing structure skin 10 by adhesive bonding or other fixing methods to form the entire outer wing skin, ensuring the external continuity of the wing skin. The inner surface of the graphene skin heat sink 1 is connected to the electronic equipment via a paraffin thermal switch 3. The paraffin thermal switch 3 regulates the temperature of the device, while the graphene skin heat sink 1 provides heat dissipation. Since the skin heat sink is a composite film material and lacks structural rigidity, the electronic equipment is anchored to the X-shaped reinforcing ribs of the wing structure skin 10 for mounting and fixing. The paraffin thermal switch 3 consists of four parts, each connected to one-quarter of the electronic equipment to avoid the X-shaped reinforcing ribs of the wing skin, forming a good contact interconnection with the graphene skin heat sink 1 and the electronic equipment.

[0027] Figure 3 This is a schematic diagram of a horizontally installed paraffin thermal switch 3. The horizontal length of the paraffin thermal switch 3 is no greater than the length of the graphene-coated heat sink 1. When the electronic device operates at high power, the temperature of the paraffin thermal switch 3 rises, and the paraffin 8, in a liquid state, fills the entire thermal switch housing 7, forming a heat path from top to bottom. The heat generated by the electronic device is conducted downwards through the paraffin thermal switch 3 to the graphene-coated heat sink 1. Utilizing the high thermal conductivity of the heat sink, rapid heat expansion is achieved, resulting in effective heat dissipation to the environment. In extremely low-temperature environments, when the electronic device is in standby or off mode, due to the low heat generation, the paraffin 8 is in a solid state at low temperatures. The solidified paraffin 8 shrinks in volume and, under the influence of gravity, accumulates at the bottom of the cavity, forming a vacuum cavity 9 at the top. This isolates the heat transfer path, thereby preventing the influence of the extremely low-temperature environment on the electronic device and controlling the temperature of the electronic device within a reasonable range, achieving a low-temperature insulation effect.

[0028] Example 2

[0029] This embodiment provides a graphene film skin thermal control device applied to an airship platform. The main difference from Embodiment 1 lies in the installation and fixing method of the skin heat dissipation device due to the different application platform. The heat-generating device and the graphene film skin thermal control device are fixed to the side skin of the airship, perpendicular to the ground. A schematic diagram of the graphene film skin thermal control device structure is shown below. Figure 6 As shown.

[0030] Figure 6 In this system, a graphene-coated heat sink 1 replaces part of the airship's outer skin, connecting to it via adhesive bonding or other fixing methods to form a unified structure, ensuring the external continuity of the airship's outer skin. The inner surface of the graphene-coated heat sink 1 is connected to the electronic equipment via a paraffin thermal switch 3. The paraffin thermal switch 3 regulates the device's temperature, while the graphene-coated heat sink 1 provides heat dissipation. The electronic equipment and the paraffin thermal switch 3 are directly fixed to the graphene-coated heat sink 1. The heat sink, being a composite film material, has relatively low structural strength, therefore it is only suitable for lightweight equipment. Given the airship's low resistance to vibration and impact loads, the heat sink can also perform some structural functions. The paraffin thermal switch 3 forms a secure contact connection with both the graphene-coated heat sink 1 and the electronic equipment.

[0031] Figure 4 This is a schematic diagram of a vertically installed paraffin thermal switch 3. When the paraffin 8 is solid, the vertical length of the vacuum chamber 9 is not less than the length of the graphene-coated heat sink 1. When the electronic device operates at high power, the temperature of the paraffin thermal switch 3 rises, and the paraffin 8, in a liquid state, fills the entire thermal switch housing 7, forming a heat path from left to right. The heat generated by the electronic device is conducted to the graphene-coated heat sink 1 via the paraffin thermal switch 3. Utilizing the high thermal conductivity of the heat sink, rapid heat expansion is achieved, resulting in effective heat dissipation to the environment. In extremely low-temperature environments, when the electronic device is in standby or off mode, due to the low heat generation, the paraffin 8 is solid at low temperatures. The solidified paraffin 8 shrinks in volume and, under the influence of gravity, accumulates at the bottom of the cavity, forming a vacuum chamber 9 at the top. This isolates the heat transfer path, thereby preventing the influence of the extremely low-temperature environment on the electronic device and controlling its temperature within a reasonable range, achieving a low-temperature insulation effect.

[0032] Because the density of the composite graphene film is significantly lower than that of high thermal conductivity metals such as aluminum and copper, or heat pipe plates, and it is thinner, and has a higher thermal conductivity, the heat dissipation surface utilization rate is high, resulting in a significantly lighter heat sink compared to traditional heat sinks. Therefore, this invention is beneficial for significantly reducing system weight and achieving lightweighting. Through the skin-based thermal control device, efficient heat dissipation between the heat source 2 and the external low-temperature environment can be achieved. Utilizing the high thermal conductivity of the composite graphene film, the heat dissipation efficiency can be further improved. Under low-temperature conditions, the thermal switch can block heat dissipation between the equipment and the external environment, improving the insulation effect and reducing the demand for electric heating power, which helps to reduce the demand for power supply resources. The skin-based thermal control device enables efficient passive heat dissipation. Compared with traditional active liquid cooling and active air cooling methods, it reduces moving parts such as water pumps, fans, and connectors, significantly improving system reliability.

[0033] Many specific details have been set forth in the foregoing description to provide a thorough understanding of the present invention. However, the above description is merely a preferred embodiment of the present invention, and the present invention can be implemented in many other ways different from those described herein. Therefore, the present invention is not limited to the specific embodiments disclosed above. Furthermore, any person skilled in the art can make many possible variations and modifications to the technical solutions of the present invention, or modify them into equivalent embodiments, using the methods and techniques disclosed above, without departing from the scope of the present invention. Any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention, without departing from the content of the present invention, shall still fall within the protection scope of the present invention.

Claims

1. A graphene membrane skin thermal control device, characterized by: The graphene skin radiator comprises a graphene core and a polyimide film, the polyimide film is located at the outer layer of the graphene core and encapsulates the graphene core, the graphene skin radiator is connected with one side of the paraffin thermal switch, and the other side of the paraffin thermal switch is connected with an external heat source; the paraffin thermal switch comprises a thermal switch shell and paraffin, the thermal switch shell is a closed structure, and the paraffin is located in the thermal switch shell; When the paraffin is in a solid state, a vacuum cavity is formed between the paraffin and the top of the thermal switch shell, and when the paraffin is in a liquid state, the paraffin fills the whole thermal switch shell; When the thermal control device is horizontally installed, the horizontal length of the paraffin thermal switch is not greater than the length of the graphene skin radiator; when the thermal control device is vertically installed, when the paraffin is in a solid state, the vertical length of the vacuum cavity is not less than the length of the graphene skin radiator.

2. A graphene membrane skin thermal control device according to claim 1, characterised in that: The graphene core comprises one or more layers of graphene, the polyimide film is uniformly distributed on the outer surface of the graphene core and is closed at the edges of the graphene core, and the outer side of the polyimide film is subjected to metalization treatment or is coated with paint.

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