Temperature rise control method for light and small electronic equipment under low thermal conductivity and low convective heat transfer conditions

Abstract

The invention provides a method for controlling temperature rise of electronic equipment under the conditions of light, small, low thermal conductivity and low convective heat transfer, which comprises the following steps of: classifying circuit boards with different power consumptions, including high-power-consumption circuit boards and medium-power-consumption circuit boards; the metal heat insulation structure of the electronic equipment adopts an aluminum alloy product and adopts natural color anodizing treatment; a high-power-consumption circuit board is placed on the outermost side of the shell, a plurality of layers of metal heat insulation structures are arranged, and a phase-change heat insulation material structure is placed between the high-power-consumption circuit board and the instrument for heat insulation; the middle-power-consumption circuit board is placed between the shell and the instrument, and a single-side heat insulation structure is adopted for heat insulation; a temperature equalizing structure is pasted on the instrument; and performing finite element transient thermal simulation analysis to obtain the steady-state temperature of the core area of the electronic equipment under the same circuit board power consumption configuration. The temperature rise rate of the core area of the electronic equipment is solved.

Description

Technical Field

[0001] This invention relates to a method for controlling the temperature rise of electronic devices under conditions of light size, low thermal conductivity, and low convective heat transfer, and belongs to the field of temperature control. Background Technology

[0002] Temperature rise control is an important technology for aerospace products, precision instruments, and microelectronic devices. Under extreme conditions of low thermal conductivity and low convection heat transfer, traditional heat dissipation methods, such as forced convection and large-size heat sinks, are ineffective and detrimental to the heat dissipation of electronic devices. This can lead to rapid temperature rise and severe heat accumulation, affecting the performance and reliability of electronic devices. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to overcome the above-mentioned shortcomings and provide a method for controlling the temperature rise of electronic devices under conditions of light size, low thermal conductivity and low convection heat transfer, so as to solve the temperature rise rate of the core area of ​​electronic devices.

[0004] The technical solution adopted in this invention is: a method for controlling the temperature rise of electronic devices under conditions of light size, low thermal conductivity, and low convective heat transfer, comprising:

[0005] Circuit boards with different power consumption are classified into high-power circuit boards and medium-power circuit boards.

[0006] The metal heat insulation structure of the electronic equipment is made of aluminum alloy and is treated with natural anodizing.

[0007] The high-power circuit board is placed on the outermost side of the housing and several layers of metal heat insulation structure are set. A phase change heat insulation material structure is placed between the high-power circuit board and the instrument for heat insulation. The medium-power circuit board is placed between the housing and the instrument and is insulated with a single-sided heat insulation structure.

[0008] A uniform temperature structure is attached to the instrument.

[0009] Finite element transient thermal simulation analysis was performed to obtain the steady-state temperature of the central region of the electronic device under the same circuit board power consumption configuration.

[0010] Furthermore, circuit boards with power consumption greater than 5W are classified as high-power circuit boards, circuit boards with power consumption less than 5W but greater than 1W are classified as medium-power circuit boards, and circuit boards with power consumption less than 1W are classified as low-power circuit boards.

[0011] Furthermore, the thickness of the metal insulation structure is not less than 2mm.

[0012] Furthermore, the phase change thermal insulation material structure includes an aluminum alloy shell, copper foam, and a phase change material, which releases heat capacity within a specific temperature range, set at 40–45°C.

[0013] Furthermore, the low-power circuit board is positioned close to the instrument.

[0014] Furthermore, the high-power circuit board and the medium-power circuit board are connected to the housing or phase change insulation material by low thermal conductivity silicone rubber, and the instrument is connected to the metal insulation structure by low thermal conductivity silicone rubber with a thermal conductivity of 1 W / (m·K).

[0015] Furthermore, the material of the isothermal structure is graphene.

[0016] Furthermore, the finite element transient thermal simulation analysis is performed to obtain the steady-state temperature of the central region of the electronic device under the same circuit board power consumption configuration, including:

[0017] Import the physical digital model of the electronic device, which includes circuit boards, housing, cover plates, heat insulation structure, instruments, and heat dissipation structure;

[0018] Configure material properties;

[0019] Perform grid generation;

[0020] Set boundary conditions, which include the thermal power consumption of each board, the environmental thermal radiation efficiency, the environmental convection heat transfer efficiency, and the simulation duration.

[0021] Post-processing settings are performed, and the above parameters are simulated through finite element simulation analysis to simulate the instrument temperature rise curve, observe whether each heat transfer path meets the design specifications, and perform iterative optimization and improvement.

[0022] Based on simulation analysis and measured data, the steady-state temperature of the electronic device under the same circuit board power consumption configuration was obtained.

[0023] Furthermore, the material properties include density, thermal conductivity, and specific heat capacity.

[0024] Furthermore, the mesh size is no greater than 3mm, and the number of meshes is no greater than 10. 6 .

[0025] The advantages of this invention compared to the prior art are:

[0026] This invention achieves passive adaptive temperature rise control, avoiding additional power consumption, eliminating reliance on traditional heat dissipation technologies, providing greater adaptability, facilitating the sealing of electronic equipment, and improving the reliability and lifespan of electronic devices. This invention employs a system-level heat dissipation design approach, delaying heat transfer at its source and significantly reducing the instrument's operating temperature; it also features more efficient heat dissipation and a heat capacity distribution within an adaptive temperature range. Attached Figure Description

[0027] Figure 1 This is a structural design layout diagram of the present invention.

[0028] Figure 2 This is a thermal conductivity diagram of the structure of the present invention;

[0029] Figure 3 This is a diagram of the temperature homogenization structure of the present invention. Detailed Implementation

[0030] The present invention will be described in conjunction with the accompanying drawings.

[0031] To address the challenges of temperature rise control in electronic devices under constraints of limited space and weight, and extreme conditions of low thermal conductivity and low convective heat transfer, optimization of thermal insulation structures, phase change material (PCM) thermal buffering, and homogenization structure design is employed. Thermal insulation structures effectively cut off the radiative heat transfer path between the heat source and the temperature control equipment. By reducing the surface emissivity of the insulation structure, radiation efficiency is reduced layer by layer, thereby effectively lowering the thermal load on the temperature control equipment. PCM can significantly increase the heat capacity and latent heat of electronic devices within a limited mass, absorbing transient heat and effectively reducing the temperature rise rate within the phase change temperature range, thus improving thermal uniformity. High thermal conductivity materials such as graphene are used to rapidly diffuse the accumulated heat region laterally through the homogenization structure, reducing contact thermal resistance. Through these measures, and further optimized using finite element topology simulation and the synergistic design of thermal insulation structures, PCM thermal buffering, and homogenization structures, the temperature rise rate under the system's thermal load is mitigated.

[0032] A design method for temperature rise control of lightweight, small electronic devices under conditions of low thermal conductivity and low convective heat transfer mainly includes the design of thermal insulation structures, phase change material thermal buffers, and temperature homogenization structures. The temperature rise control design method mainly includes the following steps:

[0033] (1) Based on the power consumption of the single board, the boards with power consumption greater than 5W are high power consumption boards, and the boards with power consumption between 1W and 5W are medium power consumption boards. Determine the number of high and medium power consumption boards.

[0034] (2) Metal insulation structures are generally made of aluminum alloy materials. To ensure the durability of aluminum alloy, natural color anodizing treatment is used.

[0035] (3) Design a metal heat insulation plate structure or phase change material as the heat insulation structure, and place the heat insulation structure between the high and medium power consumption circuit boards and the instrument. If necessary, the number of heat insulation plate layers can be increased. The high and medium power consumption circuit boards, the heat insulation structure and the instrument are connected by silicone rubber, a material with low thermal conductivity. That is, the high and medium power consumption single circuits are connected to the heat insulation material with rubber, and the heat insulation material is connected to the instrument with rubber.

[0036] (4) The instrument is mounted with a temperature equalization structure. The temperature equalization structure is made of graphene and can be directly attached to the instrument surface.

[0037] (5) Finite element transient thermal simulation verification: import solid model, set material properties, complete mesh generation, set boundary conditions, set post-processing, check simulation results, and if the results do not meet the requirements, perform iterative simulation until they meet the design requirements.

[0038] Example:

[0039] The present invention provides a method for controlling the temperature rise of electronic devices under conditions of low thermal conductivity and low convective heat transfer. The method mainly includes a thermal insulation structure, a phase change material thermal buffer, and a uniform temperature structure design.

[0040] like Figure 1 The thermal insulation structure design of this invention mainly adopts thermal insulation materials with low surface emissivity after surface treatment. Where space permits, phase change materials can be filled inside the thermal insulation material to increase the corresponding latent heat, physically isolating high-power components from instruments and minimizing radiative heat transfer between high-power components and instruments. Low thermal conductivity materials are placed along the connection path between high-power components and instruments to reduce heat conduction heat transfer between high-power components and instruments. Adding phase change materials near the instruments can absorb a large amount of latent heat and significantly delay the temperature rise, with its heat capacity being more than 3 times higher than that of metal heat sinks. A uniform temperature structure design is adopted in the temperature-sensitive area of ​​the instruments to improve the regional heat dissipation performance and temperature uniformity. Finally, the temperature rise curve of the instruments is verified through finite element simulation analysis, and iterative optimization design is completed.

[0041] The implementation steps of this invention are as follows:

[0042] 1. Classify circuit boards with different power consumption. For example, a secondary power supply circuit board has a power consumption of 20W, a computer circuit board has a power consumption of 10.5W. Circuit boards with power consumption greater than 5W are classified as high-power circuit boards. An instrument circuit board has a power consumption of 3.5W, a data acquisition circuit board has a power consumption of 2.3W, and an IF circuit board has a power consumption of 3.5W. Circuit boards with power consumption less than 5W and greater than 1W are classified as medium-power circuit boards. Circuit boards with power consumption less than 1W are classified as low-power circuit boards.

[0043] 2. All metal insulation structures are made of aluminum alloy. To reduce their surface emissivity, they are anodized in their natural color to control the surface emissivity to around 0.7.

[0044] 3. Place the high-power circuit board on the outermost side of the housing and design a multi-layered thermal insulation structure. The thickness of the metal thermal insulation structure is generally not less than 2mm. Phase change thermal insulation material can be placed between the high-power components and the instrument. The phase change thermal insulation material structure consists of an aluminum alloy shell, copper foam, and the phase change material itself. It can release a large heat capacity within a specific temperature range, generally set within the suitable operating temperature range of the instrument and slightly higher than the ambient temperature, such as 40–45℃. Medium-power circuit boards are placed between the housing and the instrument, generally using a single-sided thermal insulation structure design. Low-power circuit boards can be placed near the instrument. High-power and medium-power circuit boards are connected to the housing or phase change thermal insulation material via low thermal conductivity silicone rubber. The instrument is also connected to the metal thermal insulation structure using low thermal conductivity silicone rubber. The thermal conductivity of silicone rubber is approximately 1W / (m·K), which effectively reduces heat conduction. See [link to relevant documentation]. Figure 2 .

[0045] 4. A temperature equalization structure is attached to the instrument. This structure is primarily composed of graphene, which has a thermal conductivity of up to 2000 W / (m·K), allowing for rapid heat transfer and equalization. See the diagram for the spatial attachment effect. Figure 3 .

[0046] 5. Perform finite element transient thermal simulation analysis based on actual working conditions, importing the solid digital model, which includes circuit boards, housings, cover plates, thermal insulation structures, instruments, heat dissipation structures, etc.; set material properties, including density, thermal conductivity, specific heat capacity, etc., for example, silicone rubber material with a density of 1000 kg / m³. 3 The thermal conductivity is 1 W / (m·K), and the specific heat capacity is 1700 J / (kg·K). Mesh generation should be completed, preferably using hexahedral meshes, with a mesh size no larger than 3 mm and a mesh count no greater than 10. 6 Set boundary conditions, which should include the thermal power consumption of each board, the ambient thermal radiation efficiency, the ambient convection heat transfer efficiency, and the simulation duration. For example, the power consumption of the gyroscope circuit is 54000 W / m. 3 Each high- and medium-power circuit board is configured for radiative heat transfer with its corresponding thermal insulation structure. The emissivity is set to 0.7, and the ambient convective heat transfer efficiency is 1 W / (m²). 2 K); Post-processing settings were performed, and the above parameters were analyzed using finite element simulation to simulate the instrument's temperature rise curve. It was observed whether each heat transfer path met the design specifications, and iterative optimizations were made, such as adjusting the surface emissivity of the insulation material, the phase change temperature range of the phase change material, the area of ​​the graphene in the heat spreader, and the thickness and number of insulation layers. Simulation analysis and measured data show that, under the same circuit board power consumption configuration, the steady-state temperature of the core is reduced by approximately 10–11°C.

[0047] The parts of this invention not described in detail are well-known to those skilled in the art.

Claims

1. A method for controlling the temperature rise of lightweight, small electronic devices under conditions of low thermal conductivity and low convective heat transfer, characterized in that, include: Circuit boards with different power consumption are classified into high-power circuit boards and medium-power circuit boards. The metal heat insulation structure of the electronic equipment is made of aluminum alloy and is treated with natural anodizing. The high-power circuit board is placed on the outermost side of the housing and several layers of metal heat insulation structure are set up. A phase change heat insulation material structure is placed between the high-power circuit board and the instrument for heat insulation. The medium-power circuit board is placed between the housing and the instrument, and is insulated using a single-sided heat insulation structure. A uniform temperature structure is attached to the instrument. Finite element transient thermal simulation analysis was performed to obtain the steady-state temperature of the central region of the electronic device under the same circuit board power consumption configuration.

2. The method for controlling temperature rise of lightweight, small electronic devices under conditions of low thermal conductivity and low convective heat transfer, as described in claim 1, is characterized in that... Circuit boards with power consumption greater than 5W are classified as high-power circuit boards, circuit boards with power consumption less than 5W but greater than 1W are classified as medium-power circuit boards, and circuit boards with power consumption less than 1W are classified as low-power circuit boards.

3. The method for controlling temperature rise of lightweight, small electronic devices under conditions of low thermal conductivity and low convective heat transfer, as described in claim 1, is characterized in that... The thickness of the metal insulation structure is not less than 2mm.

4. The method for controlling temperature rise of lightweight, small electronic devices under conditions of low thermal conductivity and low convective heat transfer, as described in claim 1, is characterized in that... The phase change thermal insulation material structure includes an aluminum alloy shell, copper foam, and phase change material, which releases heat capacity within a specific temperature range, which is set at 40–45°C.

5. The method for controlling temperature rise of lightweight, small electronic devices under conditions of low thermal conductivity and low convective heat transfer, as described in claim 1, is characterized in that... The low-power circuit board is placed close to the instrument.

6. The method for controlling temperature rise of lightweight, small electronic devices under conditions of low thermal conductivity and low convective heat transfer, as described in claim 5, is characterized in that... The high-power circuit board and medium-power circuit board are connected to the shell or phase change thermal insulation material by low thermal conductivity silicone rubber, and the instrument is connected to the metal thermal insulation structure by low thermal conductivity silicone rubber. The thermal conductivity of the silicone rubber is 1W / (m·K).

7. The method for controlling temperature rise of lightweight, small electronic devices under conditions of low thermal conductivity and low convective heat transfer according to claim 1, characterized in that, The material of the isothermal structure is graphene.

8. The method for controlling temperature rise of lightweight, small electronic devices under conditions of low thermal conductivity and low convective heat transfer, as described in claim 1, is characterized in that... The finite element transient thermal simulation analysis is performed to obtain the steady-state temperature of the central region of the electronic device under the same circuit board power consumption configuration, including: Import the physical digital model of the electronic device, which includes circuit boards, housing, cover plates, heat insulation structure, instruments, and heat dissipation structure; Configure material properties; Perform grid generation; Set boundary conditions, which include the thermal power consumption of each board, the environmental thermal radiation efficiency, the environmental convection heat transfer efficiency, and the simulation duration. Post-processing settings are performed, and the above parameters are simulated through finite element simulation analysis to simulate the instrument temperature rise curve, observe whether each heat transfer path meets the design specifications, and perform iterative optimization and improvement. Based on simulation analysis and measured data, the steady-state temperature of the electronic device under the same circuit board power consumption configuration was obtained.

9. The method for controlling temperature rise of lightweight, small electronic devices under conditions of low thermal conductivity and low convective heat transfer, as described in claim 8, is characterized in that... The material properties include density, thermal conductivity, and specific heat capacity.

10. A method for controlling the temperature rise of a lightweight, small electronic device under conditions of low thermal conductivity and low convective heat transfer, as described in claim 9, is characterized in that... The mesh size is no greater than 3mm, and the number of meshes is no greater than 10. 6 .

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