CN218238504U

CN218238504U - Heat pipe

Info

Publication number: CN218238504U
Application number: CN202123443104.4U
Authority: CN
Inventors: 程璐
Original assignee: Lenovo Beijing Ltd
Current assignee: Lenovo Beijing Ltd
Priority date: 2021-12-31
Filing date: 2021-12-31
Publication date: 2023-01-06
Anticipated expiration: 2031-12-31

Abstract

The application discloses a heat pipe, which comprises a pipe shell with an evaporation section for absorbing heat and a condensation section for releasing heat, wherein a liquid absorption capillary core and a steam channel are arranged in the pipe shell; wherein, the evaporation section and/or the condensation section are/is provided with a guide layer for promoting gas-liquid separation. This application sets up the direction layer that is used for promoting gas-liquid separation at least one of evaporation zone and condensation segment, and the direction layer can make steam get into steam passage, and liquid gets into imbibition capillary core to prevent the gas-liquid mixture, reduce the influence each other that the gas-liquid flows, guarantee the phase transition circulation of gas-liquid, and then improve heat transfer performance.

Description

Heat pipe

Technical Field

The utility model relates to an electronic equipment heat dissipation technical field, more specifically say, relate to a heat pipe.

Background

Heat pipes have been commonly used in the field of heat dissipation due to their excellent thermal superconducting properties. A heat pipe generally consists of a closed tube housing and a wick disposed within the housing. The interior of the heat pipe is pumped into a negative pressure state and filled with proper liquid working medium, and the liquid has a low boiling point and is easy to volatilize.

One end of the heat pipe is an evaporation section, and the other end of the heat pipe is a condensation section; the liquid working medium is heated and evaporated by heat flow in the evaporation section, the steam flows to the condensation section under a tiny pressure difference, and the steam is cooled by cold fluid outside the pipe in the condensation section to release latent heat and is condensed into liquid; the condensate accumulated in the capillary wick of the condensation section returns to the evaporation section by virtue of the capillary force action of the capillary wick and absorbs heat for evaporation, so that the circulation is not stopped, and the heat dissipation is realized.

However, the heat pipe has a boiling limit, and particularly in an ultra-thin heat pipe, because the sectional area of an evaporation section is small, the liquid filling amount is small, when the heat flux is continuously increased, the liquid pressure is smaller than the saturated vapor pressure of a gas-liquid interface, at this time, saturated vapor is mixed in a capillary structure, and the phase change circulation of gas and liquid in the pipe is greatly influenced. And when the steam pressure is higher, the molecular heat movement is stronger, and the difference between the steam density and the water density is reduced, so the water carrying capacity of the steam can be enhanced, part of water on the outermost layer of the capillary structure can be changed into fine particles to be taken away, the gas-liquid phase change quantity is also influenced, and the heat transfer performance of the heat pipe is further influenced.

SUMMERY OF THE UTILITY MODEL

In view of the above, an object of the present invention is to disclose a heat pipe to ensure a phase change cycle of gas and liquid, thereby improving heat transfer performance.

In order to achieve the above purpose, the present application discloses the following technical solutions:

a heat pipe comprises a pipe shell with an evaporation section for absorbing heat and a condensation section for releasing heat, wherein a liquid absorption capillary core and a steam channel are arranged in the pipe shell;

wherein the evaporation section and/or the condensation section are provided with a guide layer for promoting gas-liquid separation.

Preferably, in the above heat pipe, the guiding layer includes a gas-liquid separation layer for allowing vapor to pass through and preventing liquid from passing through, and the gas-liquid separation layer is disposed on the surface of the liquid-absorbing capillary wick of the evaporation section, which is close to the vapor channel.

Preferably, in the above heat pipe, the guiding layer includes a hydrophilic layer for promoting liquid absorption, the hydrophilic layer is disposed on a surface of the wick of the condensing section near the vapor passage, and water absorption of the hydrophilic layer is stronger than water absorption of the wick.

Preferably, in the heat pipe, the wick is disposed at a central axis position inside the tube case, and the vapor passage is formed between the wick and an inner wall of the tube case.

Preferably, in the heat pipe, the guide layer further includes a hydrophobic layer for preventing condensation of the liquid, the hydrophobic layer is disposed on the inner wall of the pipe shell of the condensation section, and the hydrophobic property of the hydrophobic layer is stronger than that of the inner wall of the pipe shell.

Preferably, in the heat pipe, the hydrophobic layer is a hydrophobic film, and the hydrophilic layer is a hydrophilic film.

Preferably, in the heat pipe, a cross section of the tube case is flat, and a cross section of the wick is elliptical.

Preferably, in the heat pipe, the gas-liquid separation layer is a gas-liquid separation membrane.

Preferably, in the heat pipe, the wick is disposed on an inner wall of the tube shell, and the cavity at the central axis of the tube shell forms the vapor channel.

Preferably, in the heat pipe, the wick is a fiber wick.

According to the technical scheme, the heat pipe disclosed by the application comprises a pipe shell with an evaporation section for absorbing heat and a condensation section for releasing heat, wherein a liquid absorption capillary core and a steam channel are arranged in the pipe shell; wherein, the evaporation section and/or the condensation section are/is provided with a guide layer for promoting gas-liquid separation.

This application sets up the direction layer that is used for promoting gas-liquid separation at least one of evaporation zone and condensation segment, and the direction layer can make steam get into steam passage, and liquid gets into imbibition capillary core to prevent the gas-liquid mixture, reduce the influence each other that the gas-liquid flows, guarantee the phase transition circulation of gas-liquid, and then improve heat transfer performance.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of 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 schematic structural diagram of a heat pipe disclosed in an embodiment of the present application;

FIG. 2 isbase:Sub>A schematic cross-sectional view taken along line A-A of FIG. 1;

fig. 3 is a schematic sectional view taken along line B-B in fig. 1.

Detailed Description

The embodiment of the application discloses a heat pipe, which can ensure the phase change circulation of gas and liquid and further improve the heat transfer performance.

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments in the present application without making any creative effort belong to the protection scope of the present application.

Referring to fig. 1-3, a heat pipe disclosed in the embodiments of the present application includes a tube case 1 having an evaporation section for absorbing heat and a condensation section for releasing heat, a wick 2 and a vapor channel C being disposed in the tube case 1; wherein, the evaporation section and/or the condensation section are/is provided with a guide layer for promoting gas-liquid separation.

This application sets up the direction layer that is used for promoting gas-liquid separation at least one of evaporation zone and condensation segment, and the direction layer can make steam get into steam channel C, and liquid gets into imbibition capillary core 2 to prevent the gas-liquid mixture, reduce the influence each other that the gas-liquid flows, guarantee the phase transition circulation of gas-liquid, and then improve heat transfer performance.

In a specific embodiment, as shown in fig. 2, the guiding layer comprises a gas-liquid separation layer 3 for allowing vapor to pass and preventing liquid from passing, and the gas-liquid separation layer 3 is arranged on the surface of the liquid absorption capillary wick 2 of the evaporation section, which is close to the vapor channel C.

This embodiment utilizes outer gas-liquid separation layer 3 of imbibition capillary core 2 at the evaporation zone, only supplies steam to pass through, blocks liquid to imbibition capillary core 2 in, avoids saturated steam to take away the liquid in imbibition capillary core 2, can also overcome the influence of the shearing force of steam to liquid reflux to guarantee the gas-liquid phase transition volume, and then improve heat pipe heat transfer performance.

In a specific embodiment, as shown in fig. 3, the guiding layer comprises a hydrophilic layer 4 for promoting liquid absorption, the hydrophilic layer 4 is disposed on the surface of the wick 2 of the condensation section near the vapor passage C, and the water absorption of the hydrophilic layer 4 is stronger than that of the wick 2.

This embodiment utilizes outer hydrophilic layer 4 of imbibition capillary core 2 at the condensation segment, promotes the liquid that imbibition capillary core 2 absorbed the steam condensation, can prevent liquid at vapor passage C's stay, improves the backward flow efficiency of liquid to guarantee the gas-liquid phase transition volume, and then improve heat pipe heat transfer performance.

It is understood that the guiding layer of the present application may include the gas-liquid separation layer 3 or the hydrophilic layer 4, and may further include the gas-liquid separation layer 3 and the hydrophilic layer 4.

In a specific heat pipe, a liquid absorption capillary core 2 is arranged at the central axis position in a pipe shell 1, and a steam channel C is arranged between the liquid absorption capillary core 2 and the inner wall of the pipe shell 1. The heat pipe is provided with liquid flowing through the liquid absorption capillary core 2 at the central axis position, and a steam channel C is formed through a gap between the liquid absorption capillary core 2 and the pipe shell 1 for steam flowing; thus, the entire thickness of the heat pipe can be reduced, and the heat pipe can be applied to a case with a small thickness.

In the heat pipe of above-mentioned structure, the guiding layer still sets up in 1 inner wall of tube of condensation section including the hydrophobic layer 5 that is used for preventing the liquid condensation, hydrophobic layer 5, and the hydrophobicity of hydrophobic layer 5 is stronger than the hydrophobicity of 1 inner wall of tube.

This embodiment utilizes hydrophobic layer 5 on the inner wall of tube 1 at the condensation segment, prevents that liquid from condensing at 1 inner wall of tube, and cooperation hydrophilic layer 4 can guarantee that the liquid after the steam condensation is whole to be absorbed by imbibition capillary core 2, further improves the backward flow efficiency of liquid, avoids the evaporation zone of ultrathin pipe dry to guarantee the gas-liquid phase transition volume, and then improve heat pipe heat transfer performance.

It is to be understood that the guiding layer of the present embodiment may include one, two, or three of the gas-liquid separation layer 3, the hydrophilic layer 4, and the hydrophobic layer 5, as long as the effect of promoting gas-liquid separation in the tube case 1 is achieved.

Preferably, the hydrophobic layer 5 is a hydrophobic membrane and the hydrophilic layer 4 is a hydrophilic membrane. This embodiment increases hydrophobic membrane through the 1 inner wall of tube at the condensation segment, increases hydrophilic membrane at 2 surfaces of imbibition capillary core, guarantees that the liquid after the steam condensation is whole to be absorbed by imbibition capillary core 2, and hydrophobic membrane and hydrophilic membrane are thinner, can further attenuate the thickness of heat pipe, make moreover portably.

Alternatively, the hydrophobic layer 5 may also be other structures, such as a hydrophobic coating coated on the inner wall of the tube shell 1; the hydrophilic layer 4 may also be a hydrophilic sponge or other structures that promote liquid absorption, and the description of the present application is omitted.

Preferably, the cross section of the tube case 1 is flat, and the cross section of the wick 2 is elliptical. The heat pipe of this embodiment is the platykurtic, by being located two parallel lateral walls in middle part and two arc lateral walls of connecting two lateral wall both sides form, and thickness is thinner, can be applicable to the heat dissipation in platykurtic space, and the practicality is higher.

Certainly, according to the actual application requirement of the heat pipe, the cross section of the tube shell 1 may also be circular, oval, etc., and the cross section of the liquid-absorbing capillary core 2 may also be circular, flat, square, etc.

In order to further reduce the thickness of the heat pipe, the gas-liquid separation layer 3 is a gas-liquid separation membrane. This embodiment increases the gas-liquid separation membrane outside evaporation zone imbibition capillary core 2, only supplies steam to pass through, blocks liquid to imbibition capillary core 2 in, avoids saturated steam to take away the liquid in imbibition capillary core 2, can also overcome the influence of the shearing force of steam to liquid reflux to guarantee the gas-liquid phase transition volume, and then improve heat pipe heat transfer performance.

The gas-liquid separation membrane is thin and easy to manufacture. The gas-liquid separation layer 3 may have another structure capable of performing gas-liquid separation.

In another specific heat pipe, the liquid absorption capillary wick 2 is arranged on the inner wall of the pipe shell 1, and a cavity at the central axis of the pipe shell 1 forms a steam channel C. The heat pipe supplies liquid to flow through the liquid absorption capillary wick 2 on the inner wall of the pipe shell 1, and a steam channel C is formed through a cavity at the central axis of the pipe shell 1 to supply steam to flow; the heat pipe is generally a round heat pipe and is suitable for occasions with compact space.

To simplify the structure, the liquid-absorbent capillary wick 2 is a fibrous wick. The fiber core can be directly woven by fibers, and is convenient to manufacture. Of course, the wick 2 can also be a sintered structure or other structure capable of generating capillary force of the washing liquid.

It should be noted that, the heat pipe of the present application is used for achieving heat dissipation of electronic devices, such as ultra-thin notebook computers, mobile phones, and the like, and when the heat pipe is applied, an evaporation section of the heat pipe is close to a heating component of the electronic device, and a condensation section of the heat pipe is close to the outer side of the electronic device.

The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A heat pipe is characterized by comprising a pipe shell which is provided with an evaporation section for absorbing heat and a condensation section for releasing heat, wherein a liquid absorption capillary core and a steam channel are arranged in the pipe shell;

2. A heat pipe as claimed in claim 1 wherein said guiding layer comprises a vapor-liquid separation layer for passing vapor and blocking liquid, said vapor-liquid separation layer being disposed on a surface of said wick of said evaporator section adjacent to said vapor passage.

3. A heat pipe according to claim 1 or 2, wherein the guiding layer comprises a hydrophilic layer for promoting liquid absorption, the hydrophilic layer being provided on a surface of the wick of the condensation section near the vapor passage, the hydrophilic layer having a water absorption property stronger than that of the wick.

4. A heat pipe according to claim 3 wherein said wick is disposed at a central axis location within said shell of a tube, said vapor passage being between said wick and an inner wall of said shell of a tube.

5. A heat pipe as claimed in claim 4 wherein said guiding layer further comprises a hydrophobic layer for preventing condensation of liquid, said hydrophobic layer being disposed on an inner wall of said tube shell of said condensing section, said hydrophobic layer being more hydrophobic than an inner wall of said tube shell.

6. A heat pipe according to claim 5 wherein said hydrophobic layer is a hydrophobic membrane and said hydrophilic layer is a hydrophilic membrane.

7. A heat pipe as claimed in claim 4, wherein said tube housing is flat in cross-section and said wick is oval in cross-section.

8. A heat pipe as claimed in claim 2 wherein said vapor-liquid separation layer is a vapor-liquid separation membrane.

9. A heat pipe as claimed in claim 1 wherein said wick is disposed on an inner wall of said shell, said vapor passage being defined by a cavity at a central axis of said shell.

10. A heat pipe as claimed in claim 1 wherein said wick is a fiber wick.