Thermal management structure and method based on phase change material microcapsules

Abstract

The invention discloses a heat management structure and method based on phase change material microcapsules, and belongs to the technical field of heat management of avionic equipment. The invention discloses a heat management structure based on phase-change material microcapsules. The heat management structure comprises a phase-change material microcapsule array and a heat conduction substrate, the phase-change material microcapsule array is arranged on one surface of the heat-conducting substrate; the phase change material microcapsule array comprises a plurality of phase change material microcapsules which are arranged according to a rectangular array; the phase-change material microcapsule is composed of a core material and a coating shell coating the outer surface of the core material; the material of the core material is at least one of paraffin, fatty acid or polyethylene glycol; the wrapping shell is made of metal or ceramic. The technical problem that an existing heat management structure of avionics equipment is poor in heat dissipation efficiency is solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of thermal management of avionics equipment, and particularly relates to a thermal management structure and method based on phase change material microcapsules. Background Art

[0002] With the rapid evolution of modern aviation technology towards multi-electrification and all-electrification, the aircraft electrical system is undergoing a revolutionary architectural change. This change has elevated the system power level from the traditional kilowatt scale to the megawatt level. The continuous increase in power density has led to a non-linear growth in the heat generation per unit volume of electronic devices. Taking a high-power converter device fabricated with the third-generation wide-bandgap semiconductor material as an example, the heat flux density of its power module has exceeded the critical value of 200 watts per square centimeter, which represents an increase of nearly an order of magnitude compared to traditional silicon-based devices. Such a high heat flux density makes thermal management a core limiting factor affecting the performance indicators, reliability parameters, and service life of the aircraft electrical system. In avionics equipment, especially the transmitting module of airborne radar and the power conversion unit of the electric drive system, the heat flux density generally reaches over 200 kilowatts per square meter, and this heat load level has far exceeded the processing capacity boundary of traditional heat dissipation technologies.

[0003] Although the forced air cooling solution in the traditional heat dissipation technology system has advantages such as simple structure and convenient maintenance, due to the inherent low specific heat capacity of the air medium and the limited convective heat transfer coefficient, the maximum heat dissipation power in a sealed cabin environment is strictly limited to less than 5 kilowatts. More critically, as the flight altitude increases, the air density decreases exponentially, which further deteriorates the heat dissipation efficiency of the air cooling system. In contrast, although the liquid cooling system can achieve higher heat dissipation efficiency by using a glycol-based cooling working fluid with a high thermal conductivity, the liquid cooling system requires complex circulating pump groups and cooling pipelines, which not only significantly increases the weight of the liquid cooling system by 15 - 20 kg but also results in additional energy consumption losses, accounting for about 3% - 5% of the total power of the liquid cooling system. In addition, in the extremely low-temperature environment that an aircraft may encounter, the antifreeze problem of the coolant and the sealing reliability of the pipeline both pose severe technical challenges. These traditional heat dissipation technologies are already difficult to meet the strict requirements of the new generation of aircraft electrical systems for structural compactness, weight lightening, high reliability, and wide temperature range adaptability.

[0004] To address this series of technical challenges, the field of aerospace thermal management is actively exploring a variety of innovative solutions. Thermal management technologies based on the principle of phase change heat transfer have received extensive attention due to their unique heat energy storage and release mechanisms. Especially after adopting the microcapsule encapsulation process, the leakage problem of phase change materials is effectively solved, and the interfacial thermal resistance can be reduced to less than 0.1 °C / W. The microchannel enhanced heat transfer technology can increase the convective heat transfer coefficient to more than 10 times that of traditional technologies by constructing a channel structure with a characteristic size in the order of hundreds of micrometers. The in-plane thermal conductivity of graphene-based high thermal conductivity composites exceeds 1500 watts per meter per kelvin, providing an ideal path for the rapid diffusion of heat. At the same time, the intelligent thermal management system realizes the real-time dynamic matching of heat dissipation capacity and the optimization of energy utilization efficiency by integrating an embedded temperature sensor array, adopting a model predictive control algorithm, and configuring a variable thermal resistance adjustment device. The collaborative application of these technologies provides a thermal management solution with the characteristics of safety, efficiency, and lightweight for the next-generation aircraft electrical system.

[0005] For example, the heat flux density of the aerospace radar transmitting module has reached as high as 200 kW / m 2 , while the heat dissipation efficiency of traditional aluminum profiles is insufficient, resulting in a 30% increase in the component failure rate (maintenance data of Boeing 787); the junction temperature of the switching devices in the inverter of the electric drive system is likely to exceed 120 °C. Existing active heat dissipation solutions (such as liquid cooling) require additional pump sets, which not only increase the system weight by 15 - 20 kg but also lead to a 5% increase in energy consumption; although phase change materials (Phase Change Material; hereinafter referred to as PCM) can relieve the heat load through passive heat storage, bulk PCM has a leakage risk, and the thermal resistance at the interface with metals is as high as 0.5 °C / W, severely restricting the heat dissipation efficiency. Therefore, developing new thermal management technologies that are efficient, lightweight, and reliable has become an urgent challenge in the aerospace field. Summary of the Invention

[0006] The purpose of the present invention is to provide a thermal management structure and method based on phase change material microcapsules to solve the technical problem of poor heat dissipation efficiency of existing aerospace electronic equipment thermal management structures.

[0007] To achieve the above purpose, the present invention adopts the following technical solutions: The present invention discloses a thermal management structure based on phase change material microcapsules, including: a phase change material microcapsule array and a heat-conducting substrate; the phase change material microcapsule array is arranged on one surface of the heat-conducting substrate; the phase change material microcapsule array includes a number of phase change material microcapsules arranged in a rectangular array; The phase change material microcapsule is composed of a core material and a coating shell covering the outer surface of the core material; The material of the core material is at least one of paraffin, fatty acid and polyethylene glycol; the material of the coating shell is one or two of metal and ceramic.

[0008] Furthermore, the heat-conducting substrate has a porous structure; the porous structure is composed of a number of holes uniformly arranged on the heat-conducting substrate.

[0009] Furthermore, the aperture of the holes is 25 - 50 μm; the porosity of the porous structure on the heat-conducting substrate is 52% - 60%.

[0010] Furthermore, the material of the heat-conducting substrate is copper, aluminum, copper alloy or aluminum alloy.

[0011] Furthermore, the array density of a number of the phase change material microcapsules on one surface of the heat-conducting substrate is (1 - 8)×10 6 pieces / m 2 ; there is a spacing between adjacent rectangular arrays in a number of the rectangular arrays, and the spacing is 25 - 50 μm.

[0012] Furthermore, the thickness of the phase change material microcapsule array is 1 - 3 mm; the diameter of the phase change material microcapsule is 150 - 500 μm; The other surface of the heat-conducting substrate is provided with heat dissipation fins.

[0013] Furthermore, the phase change temperature range of the phase change material microcapsules is 40 - 120 °C, and the phase change latent heat is 180 - 300 J / g.

[0014] Furthermore, the material of the core material is C16 - C24 normal paraffin; the material of the coating shell is one or two of nickel-phosphorus alloy, silicon dioxide and copper.

[0015] The present invention also discloses a heat management method for an aircraft electrical system by using the above heat management structure based on phase change material microcapsules, including the following steps: Closely attach the phase change material microcapsule array to the surface of the electrical component in the aircraft electrical system. When the temperature of the surface of the electrical component reaches the phase change temperature range of the phase change material microcapsules, the phase change material microcapsule array reduces the temperature of the surface of the electrical component through a phase change reaction to control the temperature of the surface of the electrical component to maintain at a normal value.

[0016] Furthermore, the normal value is 40 - 85 °C; the electrical component is a power electronic device, an aviation computer or an airborne radar.

[0017] Compared with the prior art, the present invention has the following beneficial effects: The present invention discloses a thermal management structure based on phase change material microcapsules. By arranging an array of a number of phase change material microcapsules on the surface of a heat-conducting substrate, and setting the phase change material microcapsules to be composed of a core material inside and a coating shell covering the outer surface, the core material is prepared from at least one of paraffin, fatty acid or polyethylene glycol, and can form a wide temperature range phase change temperature of 40 - 120 °C, with a phase change latent heat of 180 - 300 J / g. It can buffer the instantaneous thermal shock of electrical components, effectively suppress temperature fluctuations, and cooperate with the preparation raw materials of the coating shell, metal or ceramic, to quickly transfer heat, meet the requirements of high temperature and electrical isolation, and significantly improve the heat absorption capacity of the entire structure. It can quickly absorb the heat generated by electrical components in the aircraft electrical system, effectively control the temperature rise, and solve the technical problem of poor heat dissipation efficiency of the existing thermal management structure of avionics equipment.

[0018] Furthermore, a porous structure is arranged on the surface of the heat-conducting substrate, combined with heat dissipation fins to achieve rapid diffusion and dissipation of heat, significantly improving the heat dissipation efficiency and enhancing the reliability and service life of the aircraft electrical system.

[0019] Furthermore, the distance between adjacent rectangular arrays in a number of rectangular arrays is 20 - 50 μm, and the array density of a number of phase change material microcapsules on one surface of the heat-conducting substrate is (1 - 8) × 10 6 pieces / m 2 , which can increase the contact area with electrical components and ensure conduction uniformity.

[0020] Furthermore, the material of the heat-conducting substrate is selected as copper or aluminum, which has a high heat conduction coefficient to ensure rapid heat export; copper alloy or aluminum alloy can also be used, which can improve the mechanical strength and corrosion resistance while maintaining high thermal conductivity, and is suitable for the aviation environment.

[0021] Furthermore, the phase change temperature range of the phase change material microcapsules is 40 - 120 °C, which can match the working temperature range of avionics devices to ensure precise temperature control; the phase change latent heat is 180 - 300 J / g, which can provide efficient thermal energy storage and release capabilities and extend the heat buffer time.

[0022] Furthermore, the core material is specifically selected as containing C16 - C24 normal paraffins, which can make the phase change temperature adjustable and is suitable for the thermal management requirements of different electronic devices; and the material of the coating shell is specifically selected as one or two of nickel-phosphorus alloy and silica, which can enhance the thermal conductivity and mechanical strength, and improve the chemical stability and insulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the thermal management structure based on phase change material microcapsules of the present invention; Figure 2This is the schematic structural diagram of the phase change material microcapsules of the present invention; Figure 3 This is the schematic diagram of the porous structure on the heat-conducting substrate of the present invention.

[0024] Among them: 1 - phase change material microcapsule array; 2 - heat-conducting substrate; 3 - core material; 4 - coating shell; 5 - porous structure; 6 - heat dissipation fin; 7 - electrical component. Detailed implementation manners

[0025] In order to enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0026] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily need to be used to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances, so that the embodiments of the present invention described here can be implemented in an order other than those illustrated or described here. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device including a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0027] The present invention will be further described in detail below in conjunction with the accompanying drawings: See Figure 1 As shown, the present invention discloses a thermal management structure based on phase change material microcapsules, including a phase change material microcapsule array 1. The phase change material microcapsule array 1 is arranged on one surface of a heat-conducting substrate 2, and heat dissipation fins 6 are arranged on the other surface of the heat-conducting substrate 2; among them, the phase change material microcapsule array 1 is composed of a plurality of phase change material microcapsules arranged in a rectangular array; as Figure 2 shown, the phase change material microcapsule is composed of a core material 3 and a coating shell 4 coated on the outer surface of the core material 3.

[0028] Preferably, the present invention discloses a thermal management structure based on phase change material microcapsules, including a phase change material microcapsule array 1, the phase change material microcapsule array 1 is disposed on one surface of a heat conducting substrate 2, and a heat dissipation fin 6 is disposed on the other surface of the heat conducting substrate 2; wherein, the phase change material microcapsule array 1 is composed of a plurality of phase change material microcapsules arranged in a rectangular array; the phase change material microcapsule is composed of a core material 3 and a coating shell 4 coated on the outer surface of the core material 3; the material of the core material 3 is at least one of paraffin, fatty acid and polyethylene glycol; the material of the coating shell 4 is one or two of metal and ceramic.

[0029] Preferably, the present invention discloses a thermal management structure based on phase change material microcapsules, including a phase change material microcapsule array 1, the phase change material microcapsule array 1 is disposed on one surface of a heat conducting substrate 2, and a heat dissipation fin 6 is disposed on the other surface of the heat conducting substrate 2; wherein, the phase change material microcapsule array 1 is composed of a plurality of phase change material microcapsules arranged in a rectangular array; the phase change material microcapsule is composed of a core material 3 and a coating shell 4 coated on the outer surface of the core material 3; the material of the core material 3 is at least one of paraffin, fatty acid and polyethylene glycol; the material of the coating shell 4 is one or two of metal and ceramic; the material of the core material 3 is C16-C24 normal paraffin; the material of the coating shell 4 is one or two of nickel-phosphorus alloy, silicon dioxide and copper.

[0030] Preferably, the present invention discloses a thermal management structure based on phase change material microcapsules, including a phase change material microcapsule array 1, the phase change material microcapsule array 1 is disposed on one surface of a heat conducting substrate 2, and a heat dissipation fin 6 is disposed on the other surface of the heat conducting substrate 2; wherein, the phase change material microcapsule array 1 is composed of a plurality of phase change material microcapsules arranged in a rectangular array; the phase change material microcapsule is composed of a core material 3 and a coating shell 4 coated on the outer surface of the core material 3; the material of the core material 3 is at least one of paraffin, fatty acid and polyethylene glycol; the material of the coating shell 4 is one or two of metal and ceramic; the material of the core material 3 is C16-C24 normal paraffin; the material of the coating shell 4 is one or two of nickel-phosphorus alloy, silicon dioxide and copper; the thickness of the phase change material microcapsule array 1 is 1-3 mm; the diameter of the phase change material microcapsule is 150-500 μm.

[0031] Preferably, the present invention discloses a thermal management structure based on phase change material microcapsules, including a phase change material microcapsule array 1, the phase change material microcapsule array 1 is disposed on one surface of a heat conducting substrate 2, and a heat dissipation fin 6 is disposed on the other surface of the heat conducting substrate 2; wherein, the phase change material microcapsule array 1 is composed of a plurality of phase change material microcapsules arranged in a rectangular array; the phase change material microcapsule is composed of a core material 3 and a coating shell 4 coated on the outer surface of the core material 3; the material of the core material 3 is at least one of paraffin, fatty acid and polyethylene glycol; the material of the coating shell 4 is one or two of metal and ceramic; the material of the core material 3 is C16-C24 normal paraffin; the material of the coating shell 4 is one or two of nickel-phosphorus alloy, silicon dioxide and copper; the thickness of the phase change material microcapsule array 1 is 1-3 mm; the diameter of the phase change material microcapsule is 150-500 μm; as Figure 3 shown, a porous structure 5 is disposed on the heat conducting substrate 2; the porous structure 5 is composed of a plurality of holes uniformly arranged on the heat conducting substrate 2.

[0032] Preferably, the present invention discloses a thermal management structure based on phase change material microcapsules, including a phase change material microcapsule array 1, the phase change material microcapsule array 1 is disposed on one surface of a heat conducting substrate 2, and a heat dissipation fin 6 is disposed on the other surface of the heat conducting substrate 2; wherein, the phase change material microcapsule array 1 is composed of a plurality of phase change material microcapsules arranged in a rectangular array; the phase change material microcapsule is composed of a core material 3 and a coating shell 4 coated on the outer surface of the core material 3; the material of the core material 3 is at least one of paraffin, fatty acid and polyethylene glycol; the material of the coating shell 4 is one or two of metal and ceramic; the material of the core material 3 is C16-C24 normal paraffin; the material of the coating shell 4 is one or two of nickel-phosphorus alloy, silicon dioxide and copper; the thickness of the phase change material microcapsule array 1 is 1-3 mm; the diameter of the phase change material microcapsule is 150-500 μm; a porous structure 5 is disposed on the heat conducting substrate 2; the porous structure 5 is composed of a plurality of holes uniformly arranged on the heat conducting substrate 2; the array density of a plurality of the phase change material microcapsules on one surface of the heat conducting substrate 2 is (1~8)×10 6 pcs / m 2 ; the distance between adjacent rectangular arrays in a plurality of the rectangular arrays is 25-50 μm; the aperture of the holes is 25-50 μm.

[0033] Preferably, the present invention discloses a thermal management structure based on phase change material microcapsules, including a phase change material microcapsule array 1, the phase change material microcapsule array 1 is disposed on one surface of a heat conducting substrate 2, and a heat dissipation fin 6 is disposed on the other surface of the heat conducting substrate 2; wherein, the phase change material microcapsule array 1 is composed of a plurality of phase change material microcapsules arranged in a rectangular array; the phase change material microcapsule is composed of a core material 3 and a coating shell 4 coated on the outer surface of the core material 3; the material of the core material 3 is at least one of paraffin, fatty acid and polyethylene glycol; the material of the coating shell 4 is one or both of metal and ceramic; the material of the core material 3 is a C16-C24 normal alkane; the material of the coating shell 4 is one or both of nickel-phosphorus alloy, silicon dioxide and copper; the thickness of the phase change material microcapsule array 1 is 1-3 mm; the diameter of the phase change material microcapsule is 150-500 μm; a porous structure 5 is disposed on the heat conducting substrate 2; the porous structure 5 is composed of a plurality of holes uniformly arranged on the heat conducting substrate 2; the array density of a plurality of the phase change material microcapsules on one surface of the heat conducting substrate 2 is (1~8)×10 6 pieces / m 2 ; the distance between adjacent rectangular arrays in a plurality of the rectangular arrays is 25-50 μm; the aperture of the holes is 25-50 μm; the porosity of the porous structure 5 on the heat conducting substrate 2 is 52%-60%.

[0034] Preferably, the present invention discloses a thermal management structure based on phase change material microcapsules, including a phase change material microcapsule array 1, the phase change material microcapsule array 1 is disposed on one surface of a heat conducting substrate 2, and a heat dissipation fin 6 is disposed on the other surface of the heat conducting substrate 2; wherein, the phase change material microcapsule array 1 is composed of a plurality of phase change material microcapsules arranged in a rectangular array; the phase change material microcapsule is composed of a core material 3 and a coating shell 4 coated on the outer surface of the core material 3; the material of the core material 3 is at least one of paraffin, fatty acid and polyethylene glycol; the material of the coating shell 4 is one or both of metal and ceramic; the material of the core material 3 is a C16-C24 normal alkane; the material of the coating shell 4 is one or both of nickel-phosphorus alloy, silicon dioxide and copper; the thickness of the phase change material microcapsule array 1 is 1-3 mm; the diameter of the phase change material microcapsule is 150-500 μm; a porous structure 5 is disposed on the heat conducting substrate 2; the porous structure 5 is composed of a plurality of holes uniformly arranged on the heat conducting substrate 2; the array density of a plurality of the phase change material microcapsules on one surface of the heat conducting substrate 2 is (1~8)×10 6 pieces / m 2; The spacing between adjacent rectangular arrays among several of the rectangular arrays is 25 - 50 μm; the aperture of the holes is 25 - 50 μm; the porosity of the porous structure 5 on the heat-conducting substrate 2 is 52% - 60%; the material of the heat-conducting substrate 2 is copper, aluminum, copper alloy or aluminum alloy.

[0035] Preferably, the present invention discloses a thermal management structure based on phase change material microcapsules, including a phase change material microcapsule array 1, the phase change material microcapsule array 1 is arranged on one surface of a heat-conducting substrate 2, and a heat dissipation fin 6 is arranged on the other surface of the heat-conducting substrate 2; wherein, the phase change material microcapsule array 1 is composed of several phase change material microcapsules arranged in a rectangular array; the phase change material microcapsule is composed of a core material 3 and a coating shell 4 coated on the outer surface of the core material 3; the material of the core material 3 is at least one of paraffin, fatty acid and polyethylene glycol; the material of the coating shell 4 is one or two of metal and ceramic; the material of the core material 3 is a C16 - C24 normal paraffin; the material of the coating shell 4 is one or two of nickel - phosphorus alloy, silica and copper; the thickness of the phase change material microcapsule array 1 is 1 - 3 mm; the diameter of the phase change material microcapsule is 150 - 500 μm; a porous structure 5 is arranged on the heat-conducting substrate 2; the porous structure 5 is composed of several holes uniformly arranged on the heat-conducting substrate 2; the array density of several of the phase change material microcapsules on one surface of the heat-conducting substrate 2 is (1~8)×10 6 pieces / m 2 ; The spacing between adjacent rectangular arrays among several of the rectangular arrays is 25 - 50 μm; the aperture of the holes is 25 - 50 μm; the porosity of the porous structure 5 on the heat-conducting substrate 2 is 52% - 60%; the material of the heat-conducting substrate 2 is copper, aluminum, copper alloy or aluminum alloy; the phase change temperature range of the phase change material microcapsule is 40 - 120 °C, and the phase change latent heat is 180 - 300 J / g.

[0036] The present invention also discloses a thermal management method for an aircraft electrical system using the above thermal management structure based on phase change material microcapsules, including the following steps: Attach the phase change material microcapsule array 1 closely to the surface of the electrical component 7. When the temperature on the surface of the electrical component 7 exceeds the set threshold, absorb the heat generated by the electrical component 7 through the phase change reaction of the phase change material microcapsule array 1 to control the temperature on the surface of the electrical component 7 to maintain at a normal value; the normal value is 40 - 85 °C; the electrical component 7 is a power electronic device, an aviation computer or an airborne radar.

[0037] Example 1 A thermal management structure based on phase change material microcapsules, including: It includes a phase change material microcapsule array 1 and a heat conducting substrate 2; the phase change material microcapsule array 1 is disposed on one surface of the heat conducting substrate 2; the phase change material microcapsule array 1 includes a number of phase change material microcapsules arranged in a rectangular array; the array density of the phase change material microcapsules is 5×10 6 pieces / m 2 , with a diameter of 200 μm; the thickness of the phase change material microcapsule array 1 is 2 mm; the spacing between several rectangular arrays is 30 μm; the heat conducting substrate 2 has a porous structure 5; the porous structure 5 is composed of a number of holes uniformly arranged on the heat conducting substrate 2; the aperture of the holes is 30 μm, and the porosity of the porous structure 5 on the heat conducting substrate 2 is 55%; the material of the heat conducting substrate 2 is copper; The phase change material microcapsule is composed of a core material 3 and a coating shell 4 coated on the outer surface of the core material 3; the material of the core material 3 is C16-C24 normal paraffin; the material of the coating shell 4 is nickel-phosphorus alloy; on the other surface of the heat conducting substrate 2, there is a heat dissipation fin 6; the material of the heat dissipation fin 6 is pure aluminum; In this embodiment, through testing, the phase change temperature range of the phase change material microcapsule is 55 - 85 °C, and the phase change latent heat is 220 J / g; the overall thermal conductivity of the thermal management structure based on the phase change material microcapsule is 45 W / m·K, the thermal response time is 0.8 s, and the temperature fluctuation is controlled within the range of ±2 °C.

[0038] Example 2 A thermal management structure based on phase change material microcapsules, comprising: It includes a phase change material microcapsule array 1 and a heat conducting substrate 2; the phase change material microcapsule array 1 is disposed on one surface of the heat conducting substrate 2; the phase change material microcapsule array 1 includes a number of phase change material microcapsules arranged in a rectangular array; the array density of the phase change material microcapsules is 3×10 6 pieces / m 2 , with a diameter of 350 μm; the thickness of the phase change material microcapsule array 1 is 1.5 mm; the spacing between several rectangular arrays is 40 μm; the heat conducting substrate 2 has a porous structure 5; the porous structure 5 is composed of a number of holes uniformly arranged on the heat conducting substrate 2; the aperture of the holes is 40 μm, and the porosity of the porous structure 5 on the heat conducting substrate 2 is 58%; the material of the heat conducting substrate 2 is 6061 aluminum alloy; The phase change material microcapsule is composed of a core material 3 and a coating shell 4 coated on the outer surface of the core material 3; the material of the core material 3 is a fatty acid and polyethylene glycol with a mass ratio of 6:4; the material of the coating shell 4 is silica; on the other surface of the heat conducting substrate 2, there is a heat dissipation fin 6; the material of the heat dissipation fin 6 is copper; In this embodiment, through testing, the phase change temperature range of the phase change material microcapsules is 65 - 110 °C, and the latent heat of phase change is 280 J / g; the overall thermal conductivity of the thermal management structure based on the phase change material microcapsules is 28 W / m·K, the thermal response time is 1.2 s, and the temperature fluctuation is controlled within the range of ±2 °C; and since the material of the coating shell 4 is silica, the thermal management structure based on the phase change material microcapsules has the property of preventing voltage breakdown.

[0039] Example 3 A thermal management structure based on phase change material microcapsules, comprising: It includes a phase change material microcapsule array 1 and a heat conduction substrate 2; the phase change material microcapsule array 1 is arranged on one surface of the heat conduction substrate 2; the phase change material microcapsule array 1 includes a number of phase change material microcapsules arranged in a rectangular array; the array density of the phase change material microcapsules is 8×10 6 pieces / m 2 , with a diameter of 150 μm; the thickness of the phase change material microcapsule array 1 is 1 mm; the spacing between several rectangular arrays is 25 μm; the heat conduction substrate 2 has a porous structure 5; the porous structure 5 is composed of a number of holes uniformly arranged on the heat conduction substrate 2; the aperture of the holes is 25 μm, and the porosity of the porous structure 5 on the heat conduction substrate 2 is 52%; the material of the heat conduction substrate 2 is pure aluminum; The phase change material microcapsule is composed of a core material 3 and a coating shell 4 coated on the outer surface of the core material 3; the material of the core material 3 is polyethylene glycol; the coating shell 4 has two connected inner and outer layers, where the material of the inner layer is nickel - phosphorus alloy and the material of the outer layer is silica; on the other surface of the heat conduction substrate 2, there is a heat dissipation fin 6; the material of the heat dissipation fin 6 is pure aluminum; In this embodiment, through testing, the phase change temperature range of the phase change material microcapsules is 45 - 75 °C, and the latent heat of phase change is 180 J / g; the overall thermal conductivity of the thermal management structure based on the phase change material microcapsules is 60 W / m·K, the thermal response time is 0.6 s, and the temperature fluctuation is controlled within the range of ±2 °C.

[0040] Example 4 A thermal management structure based on phase change material microcapsules, comprising: It includes a phase change material microcapsule array 1 and a heat conduction substrate 2; the phase change material microcapsule array 1 is arranged on one surface of the heat conduction substrate 2; the phase change material microcapsule array 1 includes a number of phase change material microcapsules arranged in a rectangular array; the array density of the phase change material microcapsules is 1×10 6 pieces / m 2, with a diameter of 500 μm; the thickness of the phase change material microcapsule array 1 is 3 mm; the spacing between several rectangular arrays is 50 μm; the heat-conducting substrate 2 has a porous structure 5; the porous structure 5 is composed of several holes uniformly arranged on the heat-conducting substrate 2; the aperture of the holes is 50 μm, and the porosity of the porous structure 5 on the heat-conducting substrate 2 is 60%; the material of the heat-conducting substrate 2 is Cu-10Ni (a copper alloy, specifically, nickel (Ni) is added to the copper (Cu) matrix, and the weight percentage of Ni in the copper alloy is 10%). The phase change material microcapsule is composed of a core material 3 and a coating shell 4 coated on the outer surface of the core material 3; the material of the core material 3 is paraffin and fatty acid with a mass ratio of 1:1; the coating shell 4 has two inner and outer layers connected to each other, wherein the material of the inner layer is nickel-phosphorus alloy and the material of the outer layer is copper; on the other surface of the heat-conducting substrate 2, there is a heat dissipation fin 6; the material of the heat dissipation fin 6 is pure aluminum. In this embodiment, through testing, the phase change temperature range of the phase change material microcapsule is 40 - 120 °C, and the phase change latent heat is 300 J / g; the overall thermal conductivity of the thermal management structure based on the phase change material microcapsule is 120 W / m·K, the thermal response time is 0.5 s, and the temperature fluctuation is controlled within the range of ±2 °C; and due to the materials of the coating shell 4 being nickel-phosphorus alloy and copper, the thermal management structure based on the phase change material microcapsule has good corrosion resistance.

[0041] Table 1 shows the performance statistics of the phase change material microcapsules in Examples 1 to 4, and Table 2 shows the performance statistics of the thermal management structures based on the phase change material microcapsules in Examples 1 to 4.

[0042] As can be seen from Table 1 and Table 2, by designing the phase change material microcapsules and their arrangement, the present invention can form a wide temperature range phase change temperature of 40 - 120 °C, the phase change latent heat reaches 120 - 300 J / g, and the overall thermal conductivity of the thermal management structure based on the phase change material microcapsule is 28 - 120 W / m·K, the thermal response time is 0.5 - 1.2 s. When conducting thermal management for the aircraft electrical system, the temperature fluctuation is controlled within ±2 °C, breaking through the bottleneck of the existing technology, significantly improving the heat storage capacity, thermal conductivity efficiency and reliability of the thermal management of avionics equipment, meeting the heat dissipation requirements under high power, wide temperature range and complex environments, and solving the technical problem of poor heat dissipation efficiency of the existing thermal management structure of avionics equipment.

[0043] Table 1 Performance Statistics of Phase Change Material Microcapsules in Examples 1 - 4

[0044] Table 2 Performance Statistics of Thermal Management Structures Based on Phase Change Material Microcapsules in Examples 1 - 4

[0045] The thermal management structure based on phase change material microcapsules disclosed in the present invention constructs an efficient, reliable and lightweight thermal management structure by setting phase change material microcapsules composed of a core material 3 and a coating shell 4 coated on the outer surface of the core material 3, arranging the phase change material microcapsules in a rectangular array to form a phase change material microcapsule array 1, and then combining it with a heat-conducting substrate 2 having a porous structure 5. Among them, the phase change material microcapsules are arranged in a rectangular array, and the array density is controlled at (1-8)×10 6 pieces / m 2 , and the spacing between several rectangular arrays is set to 25-50 μm. This precise arrangement design not only ensures sufficient thermal buffering capacity but also optimizes the heat flow transfer path. The diameter of the phase change material microcapsules is controlled at 150-500 μm, and the thickness of the phase change material microcapsule array 1 is 1-3 mm. This size design realizes a fast thermal response speed while ensuring sufficient heat storage capacity. The material of the coating shell 4 is one or both of metal and ceramic, which not only solves the problem of easy leakage of traditional bulk phase change materials but also reduces the interfacial thermal resistance and significantly improves the heat transfer efficiency.

[0046] When using the above thermal management structure based on phase change material microcapsules for the thermal management of an aircraft electrical system, the temperature platform characteristic of the phase change material microcapsules can accurately control the surface temperature of key devices such as power electronic devices, avionics computers, and airborne radars within a safe range of 40-85 °C, solves the problem of large temperature fluctuations in traditional heat dissipation schemes, and reduces the failure rate of electronic components; in addition, the design of the thermal management structure based on phase change material microcapsules enables it to flexibly adapt to the installation requirements of electrical components 7 with different shapes and sizes, and significantly improves the applicability in the limited space of an aircraft.

[0047] The above content is only to illustrate the technical idea of the present invention and cannot be used to limit the protection scope of the present invention. Any modification made on the basis of the technical solution according to the technical idea proposed by the present invention falls within the protection scope of the claims of the present invention.

Claims

1. A thermal management structure based on phase change material microcapsules, characterized in that, Including: A phase change material microcapsule array (1) and a heat conducting substrate (2); the phase change material microcapsule array (1) is disposed on one surface of the heat conducting substrate (2); the phase change material microcapsule array (1) includes a plurality of phase change material microcapsules arranged in a rectangular array; The phase change material microcapsule is composed of a core material (3) and a coating shell (4) coated on the outer surface of the core material (3); The material of the core material (3) is at least one of paraffin, fatty acid and polyethylene glycol; the material of the coating shell (4) is one or two of metal and ceramic.

2. The thermal management structure based on phase change material microcapsules according to claim 1, characterized in that, The heat conducting substrate (2) has a porous structure (5); the porous structure (5) is composed of a plurality of holes uniformly arranged on the heat conducting substrate (2).

3. The thermal management structure based on phase change material microcapsules according to claim 2, characterized in that, The aperture of the holes is 25 - 50 μm; the porosity of the porous structure (5) on the heat conducting substrate (2) is 52% - 60%.

4. The thermal management structure based on phase change material microcapsules according to claim 1, characterized in that The material of the heat conducting substrate (2) is copper, aluminum, copper alloy or aluminum alloy.

5. The thermal management structure based on phase change material microcapsules according to claim 1, characterized in that The array density of a number of the phase change material microcapsules on one surface of the heat-conducting substrate (2) is (1 - 8) × 10 6 pieces / m 2 ; there is a spacing between adjacent rectangular arrays in a number of the rectangular arrays, and the spacing is 25 - 50 μm.

6. The thermal management structure based on phase change material microcapsules according to claim 1, wherein The thickness of the phase change material microcapsule array (1) is 1 - 3 mm; the diameter of the phase change material microcapsule is 150 - 500 μm; Another surface of the heat conducting substrate (2) is provided with heat dissipation fins (6).

7. A thermal management structure based on phase change material microcapsules according to claim 1, characterized in that, The phase change temperature range of the phase change material microcapsule is 40 - 120 °C, and the phase change latent heat is 180 - 300 J / g.

8. A thermal management structure based on phase change material microcapsules according to claim 1, characterized in that, The material of the core material (3) is a C16 - C24 normal paraffin; the material of the coating shell (4) is one or two of nickel - phosphorus alloy, silicon dioxide and copper.

9. A thermal management method for an aircraft electrical system using a thermal management structure based on phase change material microcapsules according to any one of claims 1 to 8, characterized in that, Including the following steps: Closely attach the phase change material microcapsule array (1) to the surface of an electrical component (7) in an aircraft electrical system. When the temperature on the surface of the electrical component (7) reaches the phase change temperature range of the phase change material microcapsule, the phase change material microcapsule array (1) reduces the temperature on the surface of the electrical component (7) through a phase change reaction to control the temperature on the surface of the electrical component (7) to maintain at a normal value.

10. A method for thermal management of an aircraft electrical system using the thermal management structure based on phase change material microcapsules according to claim 9, characterized in that, The normal value is 40 - 85 °C; the electrical component (7) is a power electronic device, an aviation computer or an airborne radar.

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