Multi-metal cascade phase-change thermal insulation material

Abstract

When the multi-metal cascade phase-change thermal insulation material is used, if a phase-change metal material layer with high thermal conductivity and a high melting point is arranged adjacent to a heat source, a large amount of concentrated heat is diffused to a phase-change metal material layer with a low melting point by utilizing the high thermal conductivity of the phase-change metal material layer, and a certain temperature gradient exists between different metal material layers in the melting process; and in cooperation with heat insulation of the heat insulation layer, the effects of heat storage, temperature control, heat insulation and the like in a narrow space can be achieved, and the performance is excellent.

Description

Technical Field

[0001] The present invention relates to the technical field of heat insulation, and particularly to a multi-metal stepped phase change heat insulation material. Background Art

[0002] When some high-power devices are working, they will generate a large amount of heat, such as electron guns, engines, laser devices, strong electromagnetic devices, etc. When they are working normally, most of the energy is converted into internal energy, resulting in a large amount of heat concentrated locally, and the temperature keeps rising, seriously affecting the working performance of the devices and even causing the devices to burn out. For these high-power devices, various heat dissipation technologies are needed to cool them, achieve temperature control, and ensure the stable operation of the devices.

[0003] Recently, high-power devices are developing towards lightweight, miniaturization and high power, generating more and more concentrated heat, with a heat flux density as high as 100W / cm2 - 1000W / cm2, and the temperature of the heating area reaching hundreds or even thousands of degrees Celsius, which puts higher requirements on the compact, lightweight and efficient high-temperature thermal control and heat insulation technology.

[0004] Currently, the commonly used temperature control technology is mainly forced convection heat dissipation. By driving the coolant to quickly flush the high-temperature surface through a pump to achieve the purpose of cooling and temperature control. However, the normal operation of such temperature control technology requires a series of circulation pipelines and control systems. The overall cooling system is heavy in mass, large in volume and high in energy consumption, and cannot meet the requirements.

[0005] In response to this, there appears on the market a heat insulation and temperature control technology that combines a phase change material and a heat insulation layer. However, the configuration of this material is relatively simple, and its heat insulation performance cannot meet the requirements and needs to be improved. Summary of the Invention

[0006] To solve the above at least one technical defect, the present invention provides the following technical solutions: This application document discloses a multi-metal stepped phase change heat insulation material, including a phase change layer 1 and a heat insulation layer arranged in a stacked manner. The phase change layer 1 is of a metal stepped phase change type. The phase change layer 1 includes a plurality of phase change metal material layers. In the phase change layer 1, the phase change metal material layer with a low melting point coats the phase change metal material layer with high thermal conductivity and high melting point. The phase change metal material layer with high thermal conductivity and high melting point and the composite heat insulation layer above the phase change layer 1 are separated by a phase change metal material layer with a melting point lower than it.

[0007] During use, if a phase change metal material layer with high thermal conductivity and high melting point is arranged adjacent to the heat source, the heat transferred by the heat source to the phase change metal material layer with high thermal conductivity and high melting point uses its high thermal conductivity to diffuse a large amount of concentrated heat to the phase change metal material layer with low melting point. During the melting process, there is a certain temperature gradient between different metal material layers, and heat is stored through phase change in different temperature zones. With the heat insulation of the heat insulation layer, the effects of heat storage, temperature control, and heat insulation can be achieved simultaneously in a narrow space, and the performance is excellent.

[0008] For the phase change metal material layer in the first phase change layer, the number of layers can be selected according to requirements, such as two, three, four, etc.

[0009] For the heat insulation layer, it can be selected from the market according to requirements, such as a single heat insulation material forming or a multi-level heat insulation layer forming, or other hierarchical structures with heat insulation effects, etc.

[0010] Furthermore, the first phase change layer includes a first phase change metal material layer, a second phase change metal material layer, and a third phase change metal material layer. The third phase change metal material layer wraps the second phase change metal material layer, and the second phase change metal material layer wraps the first phase change metal material layer. In this example, the first phase change layer is composed of three phase change metal material layers. The first phase change layer has a smaller thickness while maintaining excellent heat insulation effect, and can be better arranged in a narrow space.

[0011] Furthermore, the first phase change metal material layer is formed by one or more of copper, silver, gold, aluminum or their alloys; the third phase change metal material layer is formed by one or more of gallium, indium, tin, bismuth or their alloys; the forming material of the second phase change metal material layer has a melting point between the melting points of the forming materials of the first phase change metal material layer and the third phase change metal material layer. The first phase change metal material belongs to the type with high thermal conductivity and high melting point, and its main purpose is to diffuse the concentrated heat to other regions. The second and third phase change metal material layers absorb heat through successive stepped phase changes according to different melting points. The forming material of the second phase change metal material layer can be selected from the material types of the first phase change metal material layer and the third phase change metal material layer, and only the melting point needs to be noted.

[0012] Furthermore, it further includes a first wall layer. The first phase change layer is arranged between the first wall layers or between the first wall layer and the heat insulation layer. The wall layer plays roles such as isolation and protection. For example, when the first wall layer is in contact with the heat source, the first wall layer is preferably formed by a material with high melting point and high strength, such as high-temperature titanium alloy, high-temperature steel, red copper, etc.

[0013] During use, under the heat absorption and heat storage effects of the first phase change layer, the temperature control of the first wall layer can be realized, such as keeping the temperature of the first wall layer always lower than its melting point to maintain the stability of its structure.

[0014] Furthermore, it further includes a second phase change layer, which is formed by a phase change metal with high thermal conductivity and high melting point. The second phase change layer is located on the side of the first phase change layer facing away from the heat insulation layer. The second phase change layer replaces the first wall layer to increase the heat conduction ability and quickly diffuse and transfer the heat to the first phase change layer.

[0015] Furthermore, the heat insulation layer includes a second wall layer, a vacuum chamber, a partition board, and a phase change material layer. The vacuum chamber, the partition board, and the phase change material layer are stacked between the second wall layers. The phase change material layer is separated from the first phase change layer below it by the vacuum chamber.

[0016] In this solution, a new heat insulation layer configuration is designed. The vacuum chamber separates the phase change material layer from the first phase change layer. The heat transferred from the first phase change layer is transferred to the vacuum chamber, and then the vacuum chamber transfers it to the phase change material layer. The phase change material layer absorbs and stores the heat, further reducing the heat transfer to the second wall layer above the phase change material layer, and the heat insulation effect is excellent.

[0017] Furthermore, the phase change material layer is a hydrated salt type or an organic type phase change material.

[0018] Furthermore, the phase change material layer is formed by one or more of sodium carbonate decahydrate, sodium acetate trihydrate, or paraffin.

[0019] Furthermore, it further includes a composite phase change material layer, which is of a high phase change latent heat material type. The first phase change layer or the first phase change layer and the heat insulation layer are both located in the chambers partitioned and formed in the composite phase change material layer. In this solution, the composite phase change material layer is added. The composite phase change material layer can assist the first phase change layer to absorb heat together. And the composite phase change material has a high phase change latent heat and a relatively high equivalent thermal conductivity. It can diffuse a large amount of concentrated heat to the entire area, making the temperature of the composite phase change material layer almost remain constant and stay in the medium and low temperature range or even the normal temperature range for a long time. In addition, the volume of the composite phase change material layer can change with the structural size, and it is suitable for temperature control of high-power equipment with highly concentrated heat and long-term operation in narrow spaces.

[0020] Furthermore, the composite phase change material layer includes a high thermal conductivity type skeleton and a filling material. The filling material is one or more of hydrated salt type, paraffin, or sugar alcohol type materials. The skeleton is formed by porous graphite, carbon foam, copper foam, or aluminum foam.

[0021] Compared with the prior art, the beneficial effects of the present invention are: 1. The multi-metal stepped phase change heat insulation material of the present invention is applicable to the field of high-temperature thermal control. A phase change metal material layer with high thermal conductivity and high melting point transfers concentrated heat to other phase change metal material layers with low melting point. A certain temperature gradient is formed between different metal layers, and heat is stored through phase change in different temperature zones. With the auxiliary heat insulation of the heat insulation layer, a hierarchical structure with light weight, no energy consumption, and small volume can achieve effects such as heat storage, temperature control, and heat insulation in a narrow space, and realize the temperature control of high-power equipment.

[0022] 2. The present invention designs the structural composition of the heat insulation layer, and the vacuum chamber cooperating with the phase change material layer can further improve the heat insulation effect.

[0023] 3. The present invention combines the composite phase change material layer with the first phase change layer and the heat insulation layer, which can cooperate with the first phase change layer to absorb, diffuse, and store heat, and further improve the heat insulation and temperature control effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0025] Figure 1 It is a schematic structural diagram of the present heat insulation material in Embodiment 1; Figure 2 It is a schematic structural diagram of the present heat insulation material in Embodiment 2; Figure 3 It is a schematic structural diagram of the present heat insulation material in Embodiment 3; Among them, the reference numerals are: 1. Heat source; 2. First wall layer; 3. First phase change layer; 4. Heat insulation layer; 5. Second wall layer; 6. Vacuum chamber; 7. Partition board; 8. Phase change material layer; 9. Composite phase change material layer; 10. Second phase change layer; 301. First phase change metal material layer; 302. Second phase change metal material layer; 303. Third phase change metal material layer. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0026] The following further illustrates the present invention in conjunction with the drawings and specific embodiments.

[0027] Embodiment 1: As Figure 1 shown, the present multi-metal stepped phase change heat insulation material includes a heat insulation layer 4 and a first phase change layer 3 stacked from top to bottom. The first phase change layer is of a metal stepped phase change type and is composed of multiple phase change metal material layers, such as two, three, four, or more.

[0028] In this example, a phase change layer 1 composed of three metal phase change material layers is used as an example for demonstration. The three metal phase change material layers are the first phase change metal material layer 301, the second phase change metal material layer 302, and the third phase change metal material layer 303. Among them, the first phase change metal material layer is formed of a material with a high thermal conductivity coefficient and a high melting point, such as one or more of copper, silver, gold, aluminum, or their alloys. In this example, the first phase change metal material layer is formed of silver for demonstration.

[0029] The melting point of the second phase change metal material layer 302 is lower than that of the first phase change metal material layer 301. For this, the second phase change metal material layer 302 is used to coat the top surface and side surface of the first phase change material layer 301, similar to a nested configuration. The second phase change metal material layer 302 is formed of one or more of aluminum, bismuth, tin, indium, or their alloys. In this example, the second phase change metal material is formed of aluminum for demonstration.

[0030] The melting point of the third phase change metal material layer 303 is lower than that of the second phase change metal material layer 302. For this, the third phase change metal material layer 303 is used to coat the top surface and side surface of the first phase change material layer 301. The third phase change metal material layer is formed of one or more of gallium, indium, tin, bismuth, or their alloys. In this example, the third phase change metal material layer is formed of tin for demonstration.

[0031] To isolate and protect the phase change layer 1, a wall layer 1 2 is added in this example. As Figure 1 shown, the phase change layer 1 is arranged in the chamber formed between the wall layer 1 2 and the heat insulation layer. The bottom surfaces of the first, second, and third phase change metal material layers in the phase change layer 1 abut against the inner wall surface of the wall layer 1 2. During use, if the outer wall surface of the wall layer 1 2 abuts against the heat source 1, the wall layer 1 2 is preferably formed of a material with a high melting point and high strength, specifically such as high-temperature titanium alloy, high-temperature steel, red copper, etc. In this example, the wall layer 1 is formed of red copper for demonstration. Of course, in other implementation cases, the phase change layer 1 can also be arranged in the chamber between two wall layers 1.

[0032] For the heat insulation layer, a hierarchical structure with heat insulation performance can be selected from the market according to requirements. Preferably, as Figure 1 shown in the configuration, the heat insulation layer includes a wall layer 2 5, a vacuum chamber 6, a partition 7, and a phase change material layer 8. The vacuum chamber 6, the partition 7, and the phase change material layer 8 are stacked and arranged between the wall layer 2 5. The phase change material layer 8 is separated from the phase change layer 1 below it by the vacuum chamber 6.

[0033] For the wall layer 2, the wall layer 2 in contact with the phase change layer 1 is formed of a high-melting-point titanium alloy, and the outermost wall layer 2 can be formed of a material with a slightly lower melting point, such as aluminum alloy, etc. The inner and outer wall layers 2 can be formed of different materials according to requirements.

[0034] For a vacuum chamber, that is, a chamber from which part of the air or gas is removed, the chamber between the second wall layer and the partition is evacuated to form a vacuum chamber 6, which limits the two heat transfer forms of convection and contact and has a good heat insulation effect. A phase change material layer 8 is arranged in the chamber between the partition 7 and the upper second wall layer 5. The phase change material layer selects materials according to the temperature control temperature of the adjacent second wall layer. Preferably, water and salt type phase change materials or organic type phase change materials are used, which have the advantages of high heat storage capacity and low thermal conductivity. Specifically, sodium carbonate decahydrate, sodium acetate trihydrate, paraffin wax, etc. can store the thermal radiation energy of the vacuum chamber and reduce the temperature rise of the second wall layer. In this example, the phase change material layer is shown taking paraffin wax molding as an example.

[0035] In addition, to further improve the heat insulation performance, a composite phase change material layer 9 is added in this example. The composite phase change material layer 9 is of the high phase change latent heat material type. As Figure 1 shown, a composite phase change material layer 9 is arranged in the chamber between the first wall layer 2 and the upper second wall layer 5. The first phase change layer is in the chamber formed by partitioning in the composite phase change material layer 9, Figure 1 and in the shown state, both sides of the first phase change layer are in partial contact with the corresponding composite phase change material layer 9.

[0036] For the composite phase change material layer, it includes a high thermal conductivity type skeleton and a filling material. The filling material is one or more of water and salt type, paraffin or sugar alcohol type materials. The skeleton is formed by carbon foam, porous graphite, copper foam or aluminum foam. In this example, the composite phase change material layer is formed by mixing paraffin wax and copper foam, and the ratio between the two can be selected according to requirements.

[0037] As Figure 1 shown, during use, the heat source transfers heat to the first wall layer. The first metal phase change material absorbs the concentrated heat of the first wall layer and diffuses it to the second metal phase change material layer and the third metal phase change material layer. The third metal phase change material layer melts first, and uses sensible heat and latent heat to store the heat transferred by the second metal phase change material layer, so that the temperature of the second metal phase change material layer remains almost constant and is in the medium and low temperature range.

[0038] When the third metal phase change material layer is almost completely melted, the second metal phase change material layer begins to melt and stores the heat transferred by the first phase change metal material layer during the phase change process, so that the temperature of the first metal phase change material layer remains almost constant, and the temperature of the first metal phase change material layer still remains in the medium temperature range.

[0039] When the temperature of the first wall layer in contact with the heat source is too high, the first metal phase change material layer can also melt and store the heat of the first wall layer during the phase change process, so that the temperature of the first wall layer remains almost constant and is lower than the melting point of the material of the first wall layer, which can avoid the burning of the equipment.

[0040] The heat transferred from the first self - phase - change layer to the heat - insulating layer is thermally insulated by the vacuum chamber, absorbed and stored by the phase - change material layer, etc., so that the heat transferred outside the heat - insulating layer is reduced. The composite phase - change material layer can also absorb and store the heat transferred from the first phase - change layer and the first wall layer, further reducing the heat transferred to the heat - insulating layer. In combination, the temperature rise of the second outer wall layer is reduced, achieving the required heat - insulating effect.

[0041] Example 2: As Figure 2 shown, the difference between the heat - insulating material in this example and that in Example 1 is that: the first phase - change layer 3 and the heat - insulating layer are both in the chamber formed by partitioning in the composite phase - change material layer 9. The first wall layer 3 below is in contact with the bottom surface of the composite phase - change material layer 9, which helps to achieve wall - surface temperature control and heat insulation over a short distance.

[0042] As Figure 2 shown, it is preferred to coat the phase - change material layer with a vacuum chamber to separate the phase - change material layer from the composite phase - change material layer by the vacuum chamber.

[0043] The heat source continuously acts on the first wall layer, and the temperatures of the metal phase - change material layers rise. The temperature rise is particularly significant near the heat source. When the local temperature on the surface of the third metal phase - change material layer rises to a certain value, the lower surface of the composite phase - change material layer starts to undergo a phase change and absorbs a large amount of heat. At the same time, due to the inserted high - thermal - conductivity skeleton, the equivalent thermal conductivity of the composite phase - change material layer is relatively high, effectively diffusing the concentrated heat to the entire area, so that the temperature of the composite phase - change material layer remains almost constant and is in the medium - low temperature or even normal - temperature range for a long time. Since the volume of the composite phase - change material layer can be changed according to the structural size, it is suitable for temperature control of high - power equipment working for a long time in a narrow space with highly concentrated heat.

[0044] Example 3: As Figure 3 shown, compared with the heat - insulating material in Example 1, in this example, a second phase - change layer 10 is added, and the second phase - change layer 10 replaces the first wall layer. The second phase - change layer 10 is formed by a phase - change metal with high thermal conductivity and high melting point. For example, the composition of the second phase - change layer 10 is the same as that of the first metal phase - change material layer 301 in the first phase - change layer. In this example, the second phase - change layer formed by silver is also used as an example for display.

[0045] The second phase - change layer 10 is on the side of the first phase - change layer facing away from the heat - insulating layer. The composite phase - change material layer 9 and the first phase - change layer are in the chamber between the second phase - change layer 10 and the second wall layer 5.

[0046] The heat - conduction ability is increased, and the heat is quickly diffused and transferred to the first phase - change layer and the composite phase - change material layer.

[0047] The above are only the preferred embodiments of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions falling within the concept of the present invention belong to the protection scope of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements should also be regarded as within the protection scope of the present invention.

Claims

1. A multi-metal step phase change thermal insulation material, comprising a phase change layer 1 (3) and a thermal insulation layer (4) arranged in a stacked manner, characterized in that: The phase change layer one (3) is of a metal step phase change type, and the phase change layer one (3) includes a plurality of phase change metal material layers, in which a phase change metal material layer with a low melting point is coated with a phase change metal material layer with a high thermal conductivity and a high melting point, and the phase change metal material layer with a high thermal conductivity and a high melting point is separated from a heat insulation layer (4) above the phase change layer one (3) by a phase change metal material layer with a lower melting point than the phase change metal material layer.

2. The multi-metal step-change thermal insulation material according to claim 1, characterized in that: The phase change layer 1 (3) comprises a first phase change metal material layer (301), a second phase change metal material layer (302), and a third phase change metal material layer (303); the third phase change metal material layer (303) covers the second phase change metal material layer (302), and the second phase change metal material layer (302) covers the first phase change metal material layer (301).

3. The multi-metal step-change thermal insulation material according to claim 2, characterized in that: The first phase-change metal material layer (301) is formed of one or more of copper, silver, gold, aluminum or their alloys; the third phase-change metal material layer (303) is formed of one or more of gallium, indium, tin, bismuth or their alloys; the melting point of the molding material of the second phase-change metal material layer (302) is between the melting points of the molding materials of the first phase-change metal material layer and the third phase-change metal material layer.

4. The multi-metal step-change thermal insulation material according to claim 1, characterized in that: It also includes a wall layer (2), and a phase change layer (3) is arranged between the wall layers (2) or between the wall layer (2) and the heat insulation layer (4).

5. The multi-metal step-change thermal insulation material according to claim 1, characterized in that: It also includes a second phase change layer (10), wherein the second phase change layer (10) is formed of a phase change metal with high thermal conductivity and high melting point, and the second phase change layer (10) is located on the side of the first phase change layer (3) facing away from the heat insulation layer (4).

6. The multi-metal step-change thermal insulation material according to claim 1, characterized in that: The heat insulation layer (4) comprises a second wall layer (5), a vacuum chamber (6), a partition (7), and a phase change material layer (8); the vacuum chamber (6), the partition (7), and the phase change material layer (8) are stacked between the second wall layer (5); and the phase change material layer (8) is separated from the first phase change layer (3) therebelow by the vacuum chamber (6).

7. The multi-metal step-change thermal insulation material according to claim 6, characterized in that: The phase change material layer (8) is formed of a hydrated salt type or an organic type phase change material.

8. The multi-metal step-change thermal insulation material according to claim 7, characterized in that: The phase change material layer (8) is formed from one or more of sodium carbonate decahydrate, sodium acetate trihydrate or paraffin.

9. The multi-metal step-change thermal insulation material according to any one of claims 1 to 8, characterized in that: It also includes a composite phase change material layer (9), the composite phase change material layer (9) is a high phase change latent heat material type, and the phase change layer 1 (3) or the phase change layer 1 (3) and the heat insulation layer (4) are all located in a cavity partitioned and formed in the composite phase change material layer (9).

10. The multi-metal step-change thermal insulation material according to claim 9, characterized in that: The composite phase change material layer (9) comprises a high thermal conductivity skeleton and a filling material, wherein the filling material is one or more of a water and salt type, a paraffin type or a sugar alcohol type material, and the skeleton is formed of porous graphite, carbon foam, foam copper or foam aluminum.

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