Aircraft electronic device gradient thermal control device

Abstract

The application discloses a gradient heat control device for electronic equipment of an aircraft, which comprises an FGM case and a gradient heat control module. The FGM case is fixed to the inner wall of the aircraft and serves as an electronic equipment carrier. An internal heat source is integrated into the electronic equipment. The FGM case is fixed to the inner wall of the aircraft and a PCB board, and the heat conduction coefficient of the fixed interface part of the FGM case decreases in a gradient manner, so that the heat conduction from the inner wall of the aircraft to the internal part of the electronic equipment is slowed down. The gradient heat control module is fixedly connected to the FGM case as the end cover on both sides of the electronic equipment. The gradient heat control module is filled with PCM as the heat sink of the electronic equipment. The heat conduction coefficient of the module decreases in a gradient manner from the inside to the outside. High-power chips are in reliable contact with the inner side cover plate through a thermal interface material. The inner side cover plate is designed with T-shaped fin plates embedded with metal foam materials to assist heat dissipation, so that the equivalent heat conduction coefficient of the inner side PCM is effectively improved. The outer side cover plate is made of a low-heat-conduction-coefficient material, so that the influence of high-temperature air on the equipment body is reduced.

Description

Technical Field

[0001] This invention relates to a gradient thermal control device for aircraft electronic equipment, belonging to the field of thermal management technology for aircraft electronic equipment. Background Technology

[0002] The trend towards miniaturization and high integration of electronic equipment in aircraft has led to a sharp increase in product energy density, resulting in severe overheating of internal high-power chips and a drastic decrease in the reliability of electronic equipment, making it prone to thermal failure. To address this technical problem, Chinese invention patent CN105659945B discloses a "heat dissipation device for high heat flux density and high heat loss electronic equipment," which uses an external heat spreader and pre-embedded heat pipes to dissipate heat from high heat flux density electronic equipment. However, this heat dissipation device cannot directly act on high-power electronic devices. The heat transfer process between the device and the heat dissipation device results in high equivalent thermal resistance and a large thermal conductivity gradient, making it difficult to guarantee heat dissipation efficiency. Furthermore, external heat dissipation devices also have disadvantages such as large size and weight, which contradicts the trend towards lightweight and miniaturized electronic equipment.

[0003] To improve the heat storage capacity of heat dissipation devices, Chinese invention patent CN118276644A discloses "a heat dissipation structure design method, structure, electronic device and storage medium". It uses a heat sink box to encapsulate PCM to increase the heat storage capacity of the device. However, the equivalent thermal conductivity of the heat dissipation device is limited by the thermal conductivity of the PCM itself. The heat of high power chips may not be able to be dissipated to the heat dissipation device in time, and the heat dissipation effect is not ideal.

[0004] Meanwhile, with the development of hypersonic vehicle technology, the temperature of the vehicle's internal walls and surrounding air rises rapidly during long-endurance hypersonic flight. Heat is quickly transferred to electronic equipment through conduction, convection, and radiation. Solving the problem of thermal failure of electronic equipment under the combined influence of internal and external thermal effects has become an urgent technical challenge. Summary of the Invention

[0005] The technical problem solved by this invention is: addressing the difficulty in handling the comprehensive thermal effects in existing hypersonic vehicle technology, a gradient thermal control device for aircraft electronic equipment is proposed.

[0006] The present invention solves the above-mentioned technical problem through the following technical solution: A gradient thermal control device for aircraft electronic equipment includes an FGM chassis and a gradient thermal control module, wherein: The FGM chassis houses the aircraft's electronic equipment, which is used to reduce heat conduction from the aircraft's inner wall to the FGM chassis. The gradient thermal control module is configured as an end cap structure and is fixedly installed at the top port of the FGM chassis. The gradient thermal control module is used to reduce heat conduction from the external environment to the FGM chassis and has a built-in heat sink for electronic equipment to store heat to protect the aircraft's electronic equipment. The aircraft's electronic equipment is installed inside the FGM chassis and below the gradient thermal control module. During operation, it transfers heat through the FGM chassis to the heat sink for storage.

[0007] The FGM chassis includes a chassis shell, external interfaces, and internal interfaces, wherein: The chassis has a rectangular structure with external interfaces on the side. The chassis is connected to the inner wall of the aircraft through the external interfaces. The top of the chassis has a port for matching and installing the gradient thermal control module. The inside of the chassis has an internal interface for fixing the aircraft's electronic equipment.

[0008] The chassis shell, external interface, and internal interface are made of materials with different thermal conductivity. The chassis shell, external interface, and internal interface adopt a gradient design of decreasing thermal conductivity to slow down the heat conduction from the inner wall of the aircraft to the aircraft electronic equipment connected to the internal interface. The gradient thermal control module adopts a gradient design of decreasing thermal conductivity from the inner side towards the internal interface to the outer side to improve the heat conduction on the inner side of the chassis shell and reduce the heat conduction from the external environment to the FGM chassis.

[0009] The external and internal interfaces are made of any one of the following materials: Ti6Al4V titanium alloy, Al2O3 alumina, Invar36 alloy, and Inconel718 alloy. The chassis shell is made of any one of the following materials: ER2319 aluminum alloy, 5083 aluminum alloy, and AlN. The chassis shell, external and internal interfaces are all prepared by gradient fusion using laser additive manufacturing, electron beam additive manufacturing, arc additive manufacturing, and powder metallurgy technology.

[0010] The gradient thermal control module includes an outer cover plate, an inner cover plate, T-shaped fins, and a PCM layer. The outer cover plate faces the air environment inside the aircraft to slow down the heat conduction from the outside to the chassis. The inner cover plate is located directly below the outer cover plate, and T-shaped fins are embedded in the inner cover plate to assist in heat dissipation. The PCM layer fills the cavity between the outer and inner cover plates and serves as a heat sink for electronic equipment to store heat. The inner cover plate is used to transfer the heat generated by the aircraft's electronic equipment through the chassis to the heat sink for heat storage.

[0011] The outer cover plate is made of titanium alloy; the inner cover plate is made of diamond and aluminum composite material, with a thermal conductivity greater than a preset threshold to timely export the heat generated by the internal heat source to the heat sink of the electronic device for storage.

[0012] The inner cover plate and the outer cover plate are connected by vacuum diffusion welding, vacuum brazing or electron beam welding. The outer cover plate is provided with a filling hole. The inner cover plate and the outer cover plate are filled with PCM layer through the filling hole within a preset temperature range by the filling process. The filling volume fraction of the filling process is controlled at 80%~85%. After the filling is completed, the filling hole is welded and sealed. After the welding is completed, a high temperature leak test is performed on the prepared gradient thermal control module.

[0013] The PCM layer uses paraffin material, and its heat storage capacity is enhanced by pre-setting solid density, melting point, and enthalpy ranges. The inner cover plate is designed with T-shaped fins arranged at equal intervals to enhance the equivalent thermal conductivity of the PCM layer. The method for determining the height of the T-shaped fins and the distance between adjacent surfaces is as follows:

[0014] In the formula, H The height of the fin. D The distance between adjacent surfaces at the bottom of the fin is the distance between the foam metal embedded in the T-shaped fin, with a porosity of ≥95%, and the material is selected as foam copper or foam aluminum.

[0015] The aircraft's electronic equipment includes a PCB board, a high-power chip, and a thermal interface material. It is integrated as an internal heat source. The high-power chip is soldered onto the PCB board, and the surface of the high-power chip is covered with thermal interface material and makes stable contact with the inner cover plate. The PCB board is fixed above the internal interface of the FGM chassis.

[0016] The thermal interface material is used to fill the interface gap between the high-temperature region of the internal heat source and the low-temperature region of the inner cover plate, and replaces the air layer to reduce the contact thermal resistance between the internal heat source and the inner cover plate. The thermal interface material is selected from thermally conductive silicone grease, thermally conductive gel or liquid metal.

[0017] The advantages of this invention compared to the prior art are: (1) The gradient thermal control device for aircraft electronic equipment provided by the present invention is designed with an FGM chassis with a gradient change in thermal conductivity. It makes full use of the difference in thermal conductivity of different materials, effectively reduces the input of external heat, and at the same time reduces the heat transfer from the chassis to the PCB board, providing a good working environment for the high-power chips inside the equipment. By reasonably designing the gradient of thermal conductivity inside and outside the electronic equipment, it can effectively reduce the transfer of external heat to the equipment body and achieve rapid heat dissipation of high-power chips, significantly improving the working reliability of electronic equipment under the comprehensive internal and external thermal effects. (2) The present invention designs a gradient thermal control module. The T-shaped fins and foam metal inside the module effectively improve the equivalent thermal conductivity of the PCM. The heat generated by the high-power chip can be transferred and stored in the PCM in a timely manner, and the heat dissipation effect is significantly improved. The thermal conductivity of the module decreases in a gradient from the inside to the outside, which effectively reduces the impact of high-temperature air inside the aircraft on the main body of the equipment. (3) The present invention adopts a modular design and has a compact structure, which effectively avoids the risk of thermal failure caused by the combined internal and external thermal effects without significantly increasing the size and weight of electronic devices. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the gradient thermal management device for aircraft electronic equipment provided by the present invention; Figure 2 This is a schematic diagram of the FGM chassis structure provided by the present invention; Figure 3 This is a schematic diagram of the gradient thermal control module structure provided by the present invention; Figure 4 This is a schematic diagram of the internal heat source provided by the present invention; Figure 5 This is a schematic diagram of the T-shaped fin structure provided by the present invention. Detailed Implementation

[0019] A gradient thermal control device for aircraft electronic equipment includes an FGM chassis and a gradient thermal control module. The FGM chassis serves as the carrier of the electronic equipment and is fixed to the inner wall of the aircraft. The electronic equipment is integrated as an internal heat source. The thermal conductivity of the interface between the FGM chassis and the inner wall of the aircraft and the PCB board decreases gradually, slowing down the conduction of heat from the inner wall of the aircraft to the inside of the electronic equipment. The gradient thermal control module serves as the end caps on both sides of the electronic equipment and is fixedly connected to the FGM chassis. The interior of the gradient thermal control module is filled with PCM as a heat sink for the electronic equipment. The thermal conductivity of the module decreases gradually from the inside to the outside. High-power chips can reliably contact the inner cover plate through a thermal interface material. The inner cover plate is designed with T-shaped fins with embedded metal foam material to assist in heat dissipation and effectively improve the equivalent thermal conductivity of the inner PCM. The outer cover plate is made of a low thermal conductivity material to reduce the impact of high-temperature air on the device body.

[0020] In the gradient thermal control device, the FGM chassis houses the aircraft's electronic equipment to reduce heat conduction from the aircraft's inner wall to the FGM chassis. The gradient thermal control module is configured as an end cap structure and is fixedly installed at the top port of the FGM chassis. The gradient thermal control module is used to reduce heat conduction from the external environment to the FGM chassis and has a built-in heat sink for electronic equipment to store heat to protect the aircraft's electronic equipment. The aircraft's electronic equipment is installed inside the FGM chassis and below the gradient thermal control module. During operation, it transfers heat through the FGM chassis to the heat sink for storage.

[0021] The FGM chassis includes a chassis shell, external interfaces, and internal interfaces, among which: The chassis has a rectangular structure with external interfaces on the side. The chassis is connected to the inner wall of the aircraft through the external interfaces. The top of the chassis has a port for matching and installing the gradient thermal control module. The inside of the chassis has an internal interface for fixing the aircraft's electronic equipment.

[0022] The chassis shell, external interface, and internal interface are made of materials with different thermal conductivity. The chassis shell, external interface, and internal interface adopt a gradient design of thermal conductivity to reduce the heat conduction from the inner wall of the aircraft to the aircraft electronic equipment connected to the internal interface. The gradient thermal control module adopts a gradient design of thermal conductivity from the inside to the outside of the internal interface to improve the heat conduction on the inner side of the chassis shell and reduce the heat conduction from the external environment to the FGM chassis.

[0023] The external and internal interfaces are made of any one of the following materials: Ti6Al4V titanium alloy, Al2O3 alumina, Invar36 alloy, and Inconel718 alloy. The chassis shell is made of any one of the following materials: ER2319 aluminum alloy, 5083 aluminum alloy, and AlN. The chassis shell, external interfaces, and internal interfaces are all prepared by gradient fusion using laser additive manufacturing, electron beam additive manufacturing, electric arc additive manufacturing, and powder metallurgy technology.

[0024] The gradient thermal control module includes an outer cover plate, an inner cover plate, T-shaped fins, and a PCM layer. The outer cover plate faces the air environment inside the aircraft to slow down the heat conduction from the outside to the chassis. The inner cover plate is located directly below the outer cover plate, and T-shaped fins are embedded in the inner cover plate to assist in heat dissipation. The PCM layer fills the cavity between the outer and inner cover plates and serves as a heat sink for electronic equipment to store heat. The inner cover plate is used to transfer the heat generated by the aircraft's electronic equipment through the chassis to the heat sink for heat storage.

[0025] The outer cover is made of titanium alloy; the inner cover is made of diamond and aluminum composite material, with a thermal conductivity greater than a preset threshold to promptly export the heat generated by the internal heat source to the heat sink of the electronic device for storage.

[0026] The inner cover plate and the outer cover plate are connected by vacuum diffusion welding, vacuum brazing or electron beam welding. The outer cover plate is provided with a filling hole. The inner cover plate and the outer cover plate are filled with PCM layer through the filling hole within a preset temperature range by the filling process. The filling volume fraction of the filling process is controlled at 80%~85%. After the filling is completed, the filling hole is welded and sealed. After the welding is completed, a high temperature leak test is performed on the prepared gradient thermal control module.

[0027] The PCM layer uses paraffin material, and its heat storage capacity is enhanced by pre-setting solid density, melting point, and enthalpy ranges. The inner cover plate is designed with equally spaced T-shaped fins to enhance the equivalent thermal conductivity of the PCM layer. The method for determining the height of the T-shaped fins and the distance between adjacent surfaces is as follows:

[0028] In the formula, H The height of the fin. D The distance between adjacent surfaces at the bottom of the fin is the distance between the foam metal embedded in the T-shaped fin, with a porosity of ≥95%, and the material is selected as foam copper or foam aluminum.

[0029] The aircraft's electronic equipment includes a PCB board, a high-power chip, and a thermal interface material. It is integrated as an internal heat source. The high-power chip is soldered onto the PCB board, and the surface of the high-power chip is covered with thermal interface material and makes stable contact with the inner cover plate. The PCB board is fixed above the internal interface of the FGM chassis.

[0030] Thermal interface material is used to fill the interface gap between the high-temperature area of ​​the internal heat source and the low-temperature area of ​​the inner cover plate, and replaces the air layer to reduce the contact thermal resistance between the internal heat source and the inner cover plate. Thermal interface material can be thermally conductive silicone grease, thermally conductive gel or liquid metal.

[0031] The following description, in conjunction with the accompanying drawings and preferred embodiments, provides further details: In the current embodiment, such as Figure 1 As shown, the gradient thermal control device for aircraft electronic equipment includes an FGM chassis 1, a gradient thermal control module 2, and an internal heat source 3. The FGM chassis 1 serves as the housing of the electronic equipment, the gradient thermal control module 2 serves as the end cover of the electronic equipment, and the internal heat source 3 is mounted on the FGM chassis 1. The internal heat source 3 and the gradient thermal control module 2 are in good contact, forming a complete electronic equipment.

[0032] like Figure 2 As shown, the FGM chassis 1 is made of a composite of multiple materials with a continuously gradient structure, including an external interface 11, a chassis shell 12, and an internal interface 13. The external interface 11 serves to fix electronic equipment and is in direct contact with the inner wall of the aircraft. The chassis shell 12 serves as a carrier for electronic equipment, and the internal interface 13 serves to support and fix the internal heat source 3.

[0033] External interface 11 and internal interface 13 are made of low thermal conductivity materials to slow down the conduction of heat from the aircraft's inner wall to electronic equipment. The chassis shell 12 is made of high thermal conductivity materials to quickly and evenly distribute the heat of the entire device and avoid local hot spots. The low thermal conductivity materials include, but are not limited to, Ti6Al4V titanium alloy, Al2O3 alumina, Invar36 alloy, Inconel718 alloy, etc.; the high thermal conductivity materials include, but are not limited to, ER2319 aluminum alloy, 5083 aluminum alloy, AlN, etc. The two types of materials are gradient fused using methods such as laser additive manufacturing, electron beam additive manufacturing, arc additive manufacturing, and powder metallurgy technology.

[0034] like Figure 3 As shown, the gradient thermal control module 2, serving as an end cover for electronic equipment, mainly comprises: an outer cover plate 21, an inner cover plate 22, foam metal 23, and PCM24. The outer cover plate 21 is made of titanium alloy, which can effectively slow down heat transfer when facing the high-temperature air inside the aircraft. The inner cover plate 22 is made of diamond / aluminum composite material with a thermal conductivity ≥600W / (m·K), which can promptly transfer the heat from the internal heat source 3 to the PCM24 for storage. The two cover plates are connected by vacuum diffusion welding, vacuum brazing, electron beam welding, etc. The internal cavity is filled with high-enthalpy PCM24 through the injection hole reserved in the outer cover plate 21 using a high-temperature injection process, with the injection volume fraction controlled at 80%~85%. After completion, the injection hole is welded and sealed. After welding, a high-temperature leak test is required for the gradient thermal control module 2.

[0035] PCM24 is paraffin wax with a solid density of 0.80 g / cm³. 3 ~0.90g / cm 3 It has a melting point of 75℃~78℃, an enthalpy of ≥250kJ / kg, and a thermal conductivity of 0.21W(m·K). To enhance the equivalent thermal conductivity of PCM24, the inner cover plate 22 is designed with T-shaped fins arranged at equal intervals, such as... Figure 5 As shown, the method for determining the fin height and the distance between adjacent fin surfaces is as follows:

[0036] in H The height of the fin. D The distance between adjacent surfaces at the bottom of the fin is denoted as 23. Meanwhile, foam metal 23 is embedded in the T-shaped fin with a porosity of ≥95%. The material includes, but is not limited to, foam copper and foam aluminum.

[0037] like Figure 4 As shown, the internal heat source 3 includes a PCB board 31, a high-power chip 32, and a thermal interface material 33. The high-power chip 32 is soldered onto the PCB board 31, and the thermal interface material 33 is attached to its surface, making reliable contact with the inner cover plate 22. The thermal interface material 33 can fill the gap between the high and low temperature interfaces, replacing the air layer to reduce the contact thermal resistance. It includes, but is not limited to, thermal grease, thermal gel, liquid metal, etc. The PCB board 31 is fixed on the aforementioned internal interface 13.

[0038] In the current embodiment, the external heat insulation principle of the gradient thermal control device for aircraft electronic equipment is as follows: the aircraft's inner wall and internal air are in a high-temperature environment. The FGM chassis serves as the electronic equipment's housing. The external and internal interfaces are made of low thermal conductivity materials, while the chassis housing is made of high thermal conductivity materials. The two are gradient-fused together to form a thermal conductivity gradient, effectively slowing down heat transfer from the aircraft's inner wall and the chassis to the PCB board. For the high-temperature air outside the electronic equipment, the gradient thermal control module serves as the electronic equipment's end cover and is connected to the FGM chassis. The outer cover of the gradient thermal control module has a low thermal conductivity, reducing the impact of high-temperature air on the equipment body. The inner side of the outer cover is filled with PCM as a heat sink for the electronic equipment to store heat.

[0039] The internal heat dissipation principle of the gradient thermal control device for aircraft electronic equipment is as follows: the heat generated by the high-power chip is efficiently transferred to the inner cover plate of the gradient thermal control module through the thermal interface material. The thermal interface material has a high thermal conductivity, which reduces the equivalent thermal resistance between the high-power chip and the inner cover plate. The foam metal in the T-shaped fins of the inner cover plate can significantly increase the equivalent thermal conductivity of the PCM. Taking the boundary of the T-shaped fins as the dividing line, the thermal conductivity of the PCM near the inner cover plate area is improved, while the thermal conductivity of the PCM near the outer cover plate remains unchanged, forming a gradient decrease in thermal conductivity from the inside to the outside, which is conducive to the timely conduction of chip heat to the PCM heat sink.

[0040] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications to the technical solutions of the present invention by utilizing the methods and techniques disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention shall fall within the protection scope of the technical solutions of the present invention.

[0041] The contents not described in detail in this specification are common knowledge to those skilled in the art.

Claims

1. A gradient thermal control device for aircraft electronic equipment, characterized in that: Includes the FGM chassis and gradient thermal control module, among which: The FGM chassis houses the aircraft's electronic equipment, which is used to reduce heat conduction from the aircraft's inner wall to the FGM chassis. The gradient thermal control module is configured as an end cap structure and is fixedly installed at the top port of the FGM chassis. The gradient thermal control module is used to reduce heat conduction from the external environment to the FGM chassis and has a built-in heat sink for electronic equipment to store heat to protect the aircraft's electronic equipment. The aircraft's electronic equipment is installed inside the FGM chassis and below the gradient thermal control module. During operation, it transfers heat through the FGM chassis to the heat sink for storage.

2. The gradient thermal control device for aircraft electronic equipment according to claim 1, characterized in that: The FGM chassis includes a chassis shell, external interfaces, and internal interfaces, wherein: The chassis has a rectangular structure with external interfaces on the side. The chassis is connected to the inner wall of the aircraft through the external interfaces. The top of the chassis has a port for matching and installing the gradient thermal control module. The inside of the chassis has an internal interface for fixing the aircraft's electronic equipment.

3. The gradient thermal control device for aircraft electronic equipment according to claim 2, characterized in that: The chassis shell, external interface, and internal interface are made of materials with different thermal conductivity. The chassis shell, external interface, and internal interface adopt a gradient design of decreasing thermal conductivity to slow down the heat conduction from the inner wall of the aircraft to the aircraft electronic equipment connected to the internal interface. The gradient thermal control module adopts a gradient design of decreasing thermal conductivity from the inner side towards the internal interface to the outer side to improve the heat conduction on the inner side of the chassis shell and reduce the heat conduction from the external environment to the FGM chassis.

4. The gradient thermal control device for aircraft electronic equipment according to claim 3, characterized in that: The external and internal interfaces are made of any one of the following materials: Ti6Al4V titanium alloy, Al2O3 alumina, Invar36 alloy, and Inconel718 alloy. The chassis shell is made of any one of the following materials: ER2319 aluminum alloy, 5083 aluminum alloy, and AlN. The chassis shell, external and internal interfaces are all prepared by gradient fusion using laser additive manufacturing, electron beam additive manufacturing, arc additive manufacturing, and powder metallurgy technology.

5. The gradient thermal control device for aircraft electronic equipment according to claim 3, characterized in that: The gradient thermal control module includes an outer cover plate, an inner cover plate, T-shaped fins, and a PCM layer. The outer cover plate faces the air environment inside the aircraft to slow down the heat conduction from the outside to the chassis. The inner cover plate is located directly below the outer cover plate, and T-shaped fins are embedded in the inner cover plate to assist in heat dissipation. The PCM layer fills the cavity between the outer and inner cover plates and serves as a heat sink for electronic equipment to store heat. The inner cover plate is used to transfer the heat generated by the aircraft's electronic equipment through the chassis to the heat sink for heat storage.

6. The gradient thermal control device for aircraft electronic equipment according to claim 5, characterized in that: The outer cover plate is made of titanium alloy; the inner cover plate is made of diamond and aluminum composite material, with a thermal conductivity greater than a preset threshold to timely export the heat generated by the internal heat source to the heat sink of the electronic device for storage.

7. The gradient thermal control device for aircraft electronic equipment according to claim 5, characterized in that: The inner cover plate and the outer cover plate are connected by vacuum diffusion welding, vacuum brazing or electron beam welding. The outer cover plate is provided with a filling hole. The inner cover plate and the outer cover plate are filled with PCM layer through the filling hole within a preset temperature range by the filling process. The filling volume fraction of the filling process is controlled at 80%~85%. After the filling is completed, the filling hole is welded and sealed. After the welding is completed, a high temperature leak test is performed on the prepared gradient thermal control module.

8. The gradient thermal control device for aircraft electronic equipment according to claim 7, characterized in that: The PCM layer uses paraffin material, and its heat storage capacity is enhanced by pre-setting solid density, melting point, and enthalpy ranges. The inner cover plate is designed with T-shaped fins arranged at equal intervals to enhance the equivalent thermal conductivity of the PCM layer. The method for determining the height of the T-shaped fins and the distance between adjacent surfaces is as follows: In the formula, H The height of the fin. D The distance between adjacent surfaces at the bottom of the fin is the distance between the foam metal embedded in the T-shaped fin, with a porosity of ≥95%, and the material is selected as foam copper or foam aluminum.

9. A gradient thermal control device for aircraft electronic equipment according to claim 7, characterized in that: The aircraft's electronic equipment includes a PCB board, a high-power chip, and a thermal interface material. It is integrated as an internal heat source. The high-power chip is soldered onto the PCB board, and the surface of the high-power chip is covered with thermal interface material and makes stable contact with the inner cover plate. The PCB board is fixed above the internal interface of the FGM chassis.

10. A gradient thermal control device for aircraft electronic equipment according to claim 9, characterized in that: The thermal interface material is used to fill the interface gap between the high-temperature region of the internal heat source and the low-temperature region of the inner cover plate, and replaces the air layer to reduce the contact thermal resistance between the internal heat source and the inner cover plate. The thermal interface material is selected from thermally conductive silicone grease, thermally conductive gel or liquid metal.

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