CN113840502A - One-way heat conducting device - Google Patents

Abstract

The invention discloses a unidirectional heat conduction device, which comprises: the vacuum chamber comprises a main body and a vacuum chamber body, wherein the main body is provided with a closed vacuum chamber body, and the vacuum chamber body is provided with a first surface and a second surface which are oppositely arranged; the capillary structure is arranged on the first surface, and a phase change working medium is filled in the capillary structure; the organic vesicle layer is arranged on the second surface and can expand with heat and contract with cold along with the change of temperature, and the organic vesicle layer is provided with a plurality of organic vesicles. The invention can realize unidirectional heat conduction; the heating element can be prevented from being damaged due to overheating caused by reverse heat conduction in the heat dissipation process, and excessive heat dissipation of the heating element in the heat dissipation process can be avoided; the evaporation temperature of the phase change working medium can be controlled by reasonably selecting the phase change working medium filled in the capillary structure, so that the capillary structure can be suitable for working scenes with various heat conduction requirements, and the heat conduction process can be accurately controlled.

Description

One-way heat conducting device

Technical Field

The invention belongs to the technical field of heat conducting devices, and particularly relates to a one-way heat conducting device.

Background

With the rapid progress of electronic technology, electronic components are miniaturized more and more, but the power consumption of the electronic components is larger and larger, so that the development of the electronic technology is severely restricted by the heat dissipation technology. Therefore, it becomes important to solve the problem of heat dissipation of the electronic component.

The existing heat conduction device is generally only suitable for the environment with the temperature of the electronic components being higher than the external temperature, if the external environment temperature of the equipment is too high and the electronic components are in the process, the heat conduction device cannot play a good heat dissipation effect, even the situation that the electronic components are already in a heating state and the heat conduction device still conducts the heat of the external environment to the electronic components appears, so that the electronic components are overheated, and potential safety hazards appear.

Therefore, in view of the above technical problems, it is necessary to provide a unidirectional heat conducting device.

Disclosure of Invention

The invention aims to provide a one-way heat conducting device which can prevent a heating element from being damaged due to overheating caused by reverse heat conduction in a heat radiating process and prevent the heating element from excessively radiating in the heat radiating process, so as to solve the problems in the prior art.

In order to achieve the purpose, the technical scheme provided by the invention is as follows:

a unidirectional thermally conductive apparatus, comprising:

the vacuum chamber comprises a main body and a vacuum chamber body, wherein the main body is provided with a closed vacuum chamber body, and the vacuum chamber body is provided with a first surface and a second surface which are oppositely arranged;

the capillary structure is arranged on the first surface, and a phase change working medium is filled in the capillary structure;

the organic vesicle layer is arranged on the second surface and can expand with heat and contract with cold along with the change of temperature, and the organic vesicle layer comprises a plurality of organic vesicles.

Further, the distance between the first surface and the second surface is 0.01-50 mm; and/or the boiling point of the phase change working medium in the vacuum cavity is 20-100 ℃.

Further, the phase change working medium is one of water, an aqueous solution, methanol, ethanol and acetone.

Further, the organic vesicle is filled with a mixed working medium, and the mixed working medium comprises liquid metal and a surfactant solution.

Further, the melting point of the liquid metal is not lower than 20 ℃; and/or the organic vesicle is configured as a cylinder or cone.

Further, the liquid metal is one or more of gallium, indium and tin; and/or the surfactant is one or more of alkyl sulfate, polyethylene glycol, alkyl sulfonate and alkyl dimethylamine oxide.

Further, the organic bubble layer is made of one or more of nylon 1212, polyphenylene sulfide, epoxy resin and butadiene rubber.

Further, the main body is made of a metal material and is configured in a plate shape.

Furthermore, a plurality of radiating fin groups are arranged on the outer surface of the main body.

A unidirectional thermally conductive apparatus, comprising:

the body is provided with a closed vacuum cavity;

the capillary structure is arranged on the first surface of the vacuum cavity;

a thermal expansion layer disposed on a second surface of the vacuum chamber, the thermal expansion layer being expandable when heated and in thermally conductive contact with the capillary structure;

and the capillary structure is filled with a phase change working medium, and the phase change working medium is set to enable the pressure in the vacuum cavity to be greater than the thermal expansion force of the thermal expansion layer expanding to be in heat conduction contact with the capillary structure when being heated to reach a preset gasification temperature.

The invention has the beneficial effects that:

1) unidirectional heat conduction can be realized;

2) the heating element can be prevented from being damaged due to overheating caused by reverse heat conduction in the heat dissipation process, and excessive heat dissipation of the heating element in the heat dissipation process can be avoided;

3) the vaporization temperature of the phase change working medium can be controlled by reasonably selecting the phase change working medium filled in the capillary structure, so that the method is suitable for working scenes with various heat conduction requirements, and can realize accurate control on a heat conduction process;

4) the mixed working medium in the organic vesicle contains liquid metal, the liquid metal has very high specific heat capacity and heat conductivity coefficient, and a good heat conduction effect can be realized by using a small amount of liquid metal;

5) the preparation method is simple and efficient, and is suitable for industrial production.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments described in the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

FIG. 1 is a cross-sectional view of one embodiment of the present application;

FIG. 2 is a schematic diagram of an operational scenario of the embodiment of FIG. 1;

FIG. 3 is a schematic view of another operational scenario of the embodiment of FIG. 1;

FIG. 4 is a cross-sectional view of another embodiment of the present application

Detailed Description

The present invention will be described in detail below with reference to embodiments shown in the drawings. The embodiments are not intended to limit the present invention, and structural, methodological, or functional changes made by those skilled in the art according to the embodiments are included in the scope of the present invention.

It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. In the illustrated embodiment, directional references, i.e., up, down, left, right, front, rear, etc., are relative to each other and are used to explain the relative structure and movement of the various components in the present application. These representations are appropriate when the components are in the positions shown in the figures. However, if the description of the location of an element changes, it is believed that these representations will change accordingly.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

Referring to fig. 1, a unidirectional heat conducting device according to a preferred embodiment of the present invention includes: a body 10, a capillary structure 20, and an organic vesicle layer 30.

The main body 10 is provided with a closed vacuum cavity 13, and the vacuum cavity 13 is provided with a first surface and a second surface which are oppositely arranged; the capillary structure 20 is arranged on the first surface, and the capillary structure 20 is filled with a phase change working medium; the organic vesicle layer 30 is disposed on the second surface, the organic vesicle layer 30 can expand with heat and contract with cold with the change of temperature, and the organic vesicle layer 30 includes a plurality of organic vesicles 31. Preferably, the organic cell layer 30 is made of an organic material with good coefficient of thermal expansion and contraction, and may be one or more of nylon 1212, polyphenylene sulfide, epoxy resin, and butadiene rubber.

In the present embodiment, the main body 10 is made of a metal material and is configured in a plate shape, and the plate-shaped main body 10 has a larger contact surface to rapidly absorb and transfer heat flow on the surface of the heat generating component to a larger area of the heat dissipating surface, so that heat can be rapidly dissipated, thereby reducing the heat flow density on the surface of the heat generating component. In other embodiments, the body 10 may be configured in other shapes, such as tubular, cylindrical, etc.

Specifically, the main body 10 includes a heat dissipating portion 11 and a heat absorbing portion 12 that are oppositely disposed and have a plate shape, and the heat dissipating portion 11 and the heat absorbing portion 12 jointly define a vacuum chamber 13. The inner surface of the heat dissipating unit 11 opposite to the heat absorbing unit 12 is a first surface, and the inner surface of the heat absorbing unit 12 opposite to the heat dissipating unit 11 is a second surface. The heat absorbing part 12 is attached to a heat generating component (such as a cpu, a graphic chip, a communication chip, a battery, etc.) for absorbing heat generated by the heat generating component. Preferably, the main body 10 may be made of a metal material having good heat conductivity, such as copper, aluminum, and stainless steel.

The unidirectional heat conduction device provided by the invention can realize unidirectional heat conduction. That is, the heat absorbing part 12 absorbs heat generated by the heat generating element, and then the organic bubble layer 30 disposed on the first surface is heated and expanded, and then the heat is dissipated to the heat dissipating part 11 to dissipate the heat after the organic bubble layer contacts the heat dissipating part 11. Although the organic material has poor heat conductivity under normal conditions, the vesicle wall is greatly thinned after the organic material is heated and expanded, so that the heat conductivity of the organic material can be greatly improved, and good heat conduction is realized.

Referring to fig. 2, in the above process, if the external environment temperature is high, the heat dissipation portion 11 absorbs heat, so that the phase-change working medium filled in the capillary structure 20 on the second surface is vaporized, thereby increasing the air pressure inside the vacuum cavity 13, and blocking the expansion of the organic bubble layer 30, so that the organic bubble layer 30 cannot contact the heat dissipation portion 11, and the organic bubble layer 30 has poor heat conductivity without expanding, so that it is difficult to conduct heat to the heat absorption portion 12, that is, the heat dissipation portion 11 absorbs the external heat and then guides the heat to the heat absorption portion 12, thereby protecting the heating element attached to the heat absorption portion 12. When the temperature of the external environment is reduced, the vaporized phase-change working medium is condensed into a liquid state, and then can be adsorbed in the capillary structure 20 through the capillary action.

Referring to fig. 3, if the external environment temperature is low, the organic bubble layer 30 can expand sufficiently until contacting the heat dissipation portion 11 to dissipate heat, but the heat dissipation process is changed from continuous heat dissipation to intermittent heat dissipation because the organic bubble layer 30 is rapidly cooled after contacting the heat dissipation portion 11, the organic bubble layer 30 is cooled and contracted, and is separated from the heat dissipation portion 11 after being contracted, so that heat dissipation is interrupted, but the heat absorption portion 12 continues to absorb heat of the heat generating element, and the heat dissipation process is repeated.

Specifically, the distance between the first surface and the second surface is L₁Said L is₁0.01-50 mm. The organic vesicle layer 30 has a thickness L₂Said L is₂Not more than L₁。

Distance L between the first surface and the second surface₁Can be reasonably adjusted according to the requirement of the heating element, if the heating element has the requirement on the temperature stabilityWhen the temperature control range is high, namely the temperature control range is small, if some precision instruments need to be controlled at the working temperature of 30-35 ℃, the distance L between the first surface and the second surface can be selected₁A smaller one-way heat conductor; if the temperature control range of the heating element is large, such as normal operation at 10-60 deg.C, the distance L between the first surface and the second surface can be selected₁Larger single heat conducting devices.

Thickness L of organic vesicle layer 30₂Distance L from pipe wall₁Can realize the matching when L₁And L₂I.e., when the distance between the organic bubble layer 30 and the first surface is small, the instantaneity of unidirectional heat conduction can be improved; when L is₁And L₂I.e., a larger distance between the organic bubble layer 30 and the first surface, a certain time delay can be generated by the unidirectional thermal conduction.

Specifically, the boiling point of the phase change working medium in the vacuum cavity 13 is 20-100 ℃. The phase-change working medium can be pure water, aqueous solution, alcohols, ketones and other inorganic or organic compounds. Preferably, the phase change working medium is one of pure water, an aqueous solution, methanol, ethanol and acetone. The aqueous solution can be sodium chloride aqueous solution, and the sodium chloride aqueous solutions with different concentrations have different boiling points and can be selected according to actual conditions.

The phase change working medium can be reasonably selected according to different working scenes, for example, when the phase change working medium with the boiling point of 20 ℃ is selected in the vacuum cavity 13, if the external environment temperature is higher than 20 ℃, the phase change working medium is vaporized, so that the air pressure in the vacuum cavity 13 is increased, and the expansion of the organic bubble layer 30 is hindered, and at the moment, even if the temperature of the heat absorption part 12 is higher than the external environment temperature, the heat conduction from the heat absorption part 12 to the heat dissipation part 11 is difficult to realize; if a phase change working medium with a boiling point of 100 ℃ is selected in the vacuum cavity 13, the air pressure in the vacuum cavity 13 cannot be affected as long as the external environment temperature is lower than 100 ℃ and the phase change working medium cannot be vaporized, so that the expansion of the organic bubble layer 30 cannot be hindered, and at this time, even if the external environment temperature is at a higher temperature (lower than the temperature of the boiling point of the phase change working medium in the vacuum cavity 13), the heat absorption part 12 can still realize the heat conduction to the heat dissipation part 11.

Specifically, the organic vesicle 31 is filled with a mixed working medium, which mainly comprises a liquid metal and a surfactant solution (aqueous solution). Wherein, the mass fraction of the liquid metal in the mixed working medium is 10-60%, the mass fraction of the surfactant solution is 40-90%, and the mass concentration of the surfactant in the surfactant solution is 0.01-5%. The mixed working medium generates a large amount of micro bubbles after being heated, so that the liquid metal melted by heating can be dispersed into a large amount of micro metal droplets and fully dispersed in the surfactant solution, and further good heat conduction is realized by utilizing the excellent heat conduction performance of the liquid metal.

The melting point of the liquid metal is not lower than 20 ℃, and preferably, the melting point of the liquid metal is one or more of gallium, indium and tin. The surfactant may be anionic surfactant, cationic surfactant or nonionic surfactant, and is selected according to the kind of the liquid metal, and is preferably one or more of alkyl sulfate, polyethylene glycol, alkyl sulfonate and alkyl dimethylamine oxide.

Specifically, the organic vesicle 31 is configured in a cylindrical or conical shape.

The shape of the organic vesicle 31 also has a certain influence on heat dissipation, and can be selected according to the requirements of the heating element. The organic vesicles 31, such as columnar or conical organic vesicles, have more directivity and are more biased toward heat conduction from the heat absorbing portion 12 to the heat dissipating portion 11 than the spherical organic vesicles 31.

Specifically, the outer surface of the main body 10 is provided with a plurality of heat dissipating fin sets. Preferably, the heat dissipating fin group is disposed on an outer surface of the heat dissipating portion 11. The arrangement of the heat dissipation fin group can increase the heat dissipation area of the heat dissipation part 11, thereby realizing better heat dissipation effect.

Referring to fig. 4, a unidirectional heat conducting device according to another embodiment of the present invention includes:

a body 40 having a sealed vacuum chamber 43;

a capillary structure 50 disposed on the first surface 41 of the vacuum chamber 43;

a thermal expansion layer 60 disposed on the second surface 42 of the vacuum chamber 43, the thermal expansion layer 60 being expandable when heated and in thermally conductive contact with the wicking structure 50;

the capillary structure 50 is filled with a phase change working medium, and the phase change working medium is set to make the pressure in the vacuum cavity 43 greater than the thermal expansion force of the thermal expansion layer 60 expanding to be in heat conduction contact with the capillary structure 50 when being heated to reach a predetermined gasification temperature.

Preferably, the first surface 41 and the second surface 42 of the vacuum chamber 43 are oppositely disposed.

Preferably, the thermally expandable layer 60 is an organic vesicle layer of a specific vesicle structure 61.

Preferably, the boiling point of the phase change working medium in the vacuum cavity 43 is 20-100 ℃. The phase-change working medium can be pure water, aqueous solution, alcohols, ketones and other inorganic or organic compounds. The aqueous solution can be sodium chloride aqueous solution, and the sodium chloride aqueous solutions with different concentrations have different boiling points and can be selected according to actual conditions.

The preparation method of the unidirectional heat conduction device in one embodiment of the invention comprises the following steps:

providing a first metal plate as a heat dissipation part 11, and performing cleaning treatment on the surface of the first metal plate, wherein the cleaning treatment specifically comprises conventional cleaning treatment such as removing oxide scales, removing oil, cleaning and drying;

sintering a layer of metal capillary structure 20 on a surface of a first metal plate;

providing a second metal plate as a heat absorption part 12, and pretreating the surface of the second metal plate by using hydrochloric acid with certain concentration to coat the surface with a strong acid film;

preparing an organic solution, placing liquid metal into a surfactant solution, stirring for 0.5-3 h to uniformly mix the liquid metal and the surfactant solution, then adding a volatile organic solvent and an organic substance with a good thermal expansion coefficient (such as nylon 1212, polyphenylene sulfide, epoxy resin, butadiene rubber and the like), and uniformly stirring to obtain the organic solution;

coating a layer of the organic solution on one surface of the second metal plate, drying, coating a layer again, repeating the above operation to form an organic bubble layer 30, and coating several layers according to the actual thickness requirement;

covering the surface of the first metal plate with the capillary structure 20 opposite to the surface of the second metal plate with the organic bubble layer 30, and welding to form a cavity with a certain height between the first metal plate and the second metal plate;

and filling a phase change working medium in the capillary structure 20 on the first metal plate, vacuumizing, and sealing to obtain the unidirectional heat conduction device.

The unidirectional heat conduction device provided by the invention can be applied to a battery system of a new energy automobile, and the unidirectional heat conduction device is additionally arranged on a battery pack of the new energy automobile, so that the problem that the battery pack is too cold or too hot and cannot be deeply discharged can be avoided.

The unidirectional heat conduction device provided by the invention has the following advantages:

1) unidirectional heat conduction can be realized;

2) the heating element can be prevented from being damaged due to overheating caused by reverse heat conduction in the heat dissipation process, and excessive heat dissipation of the heating element in the heat dissipation process can be avoided;

3) the vaporization temperature of the phase change working medium can be controlled by reasonably selecting the phase change working medium filled in the capillary structure 20, so that the method is suitable for working scenes with various heat conduction requirements, and can realize accurate control on a heat conduction process;

4) the mixed working medium in the organic vesicle 31 contains liquid metal, the liquid metal has very high specific heat capacity and heat conductivity coefficient, and a good heat conduction effect can be realized by using a small amount of liquid metal;

5) the preparation method is simple and efficient, and is suitable for industrial production.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.

Claims (10)

1. A unidirectional heat transfer device, comprising:

the vacuum chamber comprises a main body and a vacuum chamber body, wherein the main body is provided with a closed vacuum chamber body, and the vacuum chamber body is provided with a first surface and a second surface which are oppositely arranged;

the capillary structure is arranged on the first surface, and a phase change working medium is filled in the capillary structure;

the organic vesicle layer is arranged on the second surface and can expand with heat and contract with cold along with the change of temperature, and the organic vesicle layer comprises a plurality of organic vesicles.

2. A unidirectional heat conduction device according to claim 1, wherein the distance between the first surface and the second surface is 0.01-50 mm; and/or the boiling point of the phase change working medium in the vacuum cavity is 20-100 ℃.

3. The unidirectional heat conduction device of claim 2, wherein the phase change working medium is one of water, an aqueous solution, methanol, ethanol and acetone.

4. The unidirectional heat conduction device according to claim 1, wherein the organic vesicle is filled with a mixed working medium, and the mixed working medium comprises a liquid metal and a surfactant solution.

5. A unidirectional heat transfer device as claimed in claim 4, wherein the liquid metal has a melting point of not less than 20 ℃; and/or the organic vesicle is configured as a cylinder or cone.

6. A unidirectional heat transfer device as claimed in claim 5, wherein the liquid metal is one or more of gallium, indium and tin; and/or the surfactant is one or more of alkyl sulfate, polyethylene glycol, alkyl sulfonate and alkyl dimethylamine oxide.

7. A unidirectional heat transfer device as claimed in claim 1, wherein the organic bladder layer is made of one or more of nylon 1212, polyphenylene sulfide, epoxy resin and oxybutylene rubber.

8. A unidirectional heat transfer apparatus according to claim 1, wherein the main body is made of a metal material and is configured in a plate shape.

9. A unidirectional heat transfer device as claimed in claim 8, wherein the body has a plurality of sets of fins on its outer surface.

10. A unidirectional heat transfer device, comprising:

the body is provided with a closed vacuum cavity;

the capillary structure is arranged on the first surface of the vacuum cavity;

a thermal expansion layer disposed on a second surface of the vacuum chamber, the thermal expansion layer being expandable when heated and in thermally conductive contact with the capillary structure;

and the capillary structure is filled with a phase change working medium, and the phase change working medium is set to enable the pressure in the vacuum cavity to be greater than the thermal expansion force of the thermal expansion layer expanding to be in heat conduction contact with the capillary structure when being heated to reach a preset gasification temperature.

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