CN114383447A

CN114383447A - Evaporator and loop heat pipe

Info

Publication number: CN114383447A
Application number: CN202011141752.1A
Authority: CN
Inventors: 李碧莹; 李帅; 徐青松
Original assignee: Nanjing ZTE New Software Co Ltd
Current assignee: Nanjing ZTE New Software Co Ltd
Priority date: 2020-10-22
Filing date: 2020-10-22
Publication date: 2022-04-22

Abstract

The utility model provides an evaporator, evaporator includes casing and capillary sandwich layer, capillary sandwich layer sets up in the casing, and will space separation in the casing becomes collection vapour chamber and stock solution chamber, be formed with on the casing with the communicating steam port in collection vapour chamber and with the communicating liquid mouth that returns in stock solution chamber, the casing is including being used for the heat-conducting plate with the electronic equipment contact, wherein, be formed with at least one heat conduction rib on the internal surface of heat-conducting plate, the embedding of heat conduction rib in the capillary sandwich layer. The present disclosure also provides a loop heat pipe. The evaporator can be installed in a limited space and has high evaporation efficiency.

Description

Evaporator and loop heat pipe

Technical Field

The invention relates to the field of electronic equipment heat dissipation, in particular to an evaporator and a loop heat pipe comprising the evaporator.

Background

With the demand of consumers for miniaturization of electronic devices, the degree of integration of electronic devices is also increasing. The higher integration degree of the electronic device means that the amount of heat generated per unit area of the electronic device is larger, and thus the heat dissipation device needs to dissipate the heat of the electronic device.

One commonly used heat dissipation device for dissipating heat from electronic equipment is a loop heat pipe. Common loop heat pipes include an evaporator, a condenser, a reservoir, a vapor line, a liquid line, and the like.

When the loop heat pipe works, the evaporator is arranged on the electronic equipment and is subjected to heat load, so that the working medium in the evaporator is evaporated in the capillary core layer in the evaporator and enters the condenser through the evaporation pipeline. The steam is condensed into liquid working medium in the condenser, and the liquid working medium flows back to the liquid storage device through the liquid pipeline, and the working medium which is recovered to be in a liquid state is further supplied to the evaporator through the liquid storage device.

With the high integration of electronic devices, there is still a need to improve the heat dissipation efficiency of loop heat pipes.

Disclosure of Invention

The present disclosure provides an evaporator and a loop heat pipe.

As the first aspect of this disclosure, provide an evaporator, the evaporator includes casing and capillary core layer, capillary core layer sets up in the casing, and will space separation in the casing becomes collection vapour chamber and stock solution chamber, be formed with on the casing with the communicating steam port in collection vapour chamber and with the communicating liquid return mouth in stock solution chamber, the casing is including being used for the heat-conducting plate with the electronic equipment contact, wherein, be formed with at least one heat conduction rib on the internal surface of heat-conducting plate, the embedding of heat conduction rib is in the capillary core layer.

Optionally, the capillary core layer includes a first capillary core layer and a second capillary core layer stacked on the first capillary core layer, the first capillary core layer is disposed opposite to the heat conducting plate, at least one vapor channel is formed on the first capillary core layer, and an outlet of the vapor channel is communicated with the vapor collecting cavity.

Optionally, the length direction of the steam channel is consistent with the length direction of the heat-conducting rib.

Optionally, the evaporator comprises a plurality of heat-conducting ribs and a plurality of steam channels, the steam channels and the heat-conducting ribs being arranged alternately.

Optionally, the pore size of the second capillary core layer is larger than the pore size of the first capillary core layer.

Optionally, the pore size of the first capillary core layer is between 10 microns and 50 microns, and the pore size of the second capillary core layer is between 50 microns and 200 microns.

Optionally, at least one auxiliary fluid supplementing channel is formed in the second capillary core layer, an outlet of the auxiliary fluid supplementing channel is communicated with the liquid storage cavity, and the auxiliary fluid supplementing channel extends from the liquid storage cavity to the vapor collecting cavity.

Optionally, the top opening of the auxiliary fluid replenishing channel is covered and closed by the housing.

Optionally, the auxiliary fluid replenishing channel is formed inside the second capillary core layer.

As a second aspect of the present disclosure, a loop heat pipe is provided, where the loop heat pipe includes an evaporator, a condenser, a vapor pipeline and a liquid pipeline, one end of the vapor pipeline is communicated with a vapor port of the evaporator, the other end of the vapor pipeline is communicated with a vapor inlet of the condenser, one end of the liquid pipeline is communicated with a liquid return port of the evaporator, the other end of the liquid pipeline is communicated with a liquid outlet of the condenser, and the evaporator is the evaporator provided in the first aspect of the present disclosure.

The evaporator is used in the loop heat pipe, specifically, a steam port of the evaporator is communicated with one end of a steam pipeline, the other end of the steam pipeline is communicated with a steam inlet of the condenser, a liquid return port of the evaporator is communicated with one end of a liquid pipeline, and the other end of the liquid pipeline is communicated with a liquid outlet of the condenser.

When the loop heat pipe works, a liquid working medium is arranged in the liquid storage cavity, and the heat conducting plate is in contact with the electronic equipment and bears heat load. The capillary core layer is provided with a plurality of capillary holes, under the action of capillary effect, liquid working medium enters the capillary holes and is evaporated on the surfaces of the capillary holes, generated steam enters the steam collecting cavity, escapes from the evaporator through the steam port, enters the steam pipeline connected with the steam port, enters the condenser through the steam pipeline and is condensed by the condenser to form the liquid working medium. And the liquid working medium enters the liquid storage cavity of the evaporator through a liquid pipeline and further repeats the circulation.

Because the heat conducting ribs are additionally arranged on the heat conducting plate of the evaporator, the inner surface area of the shell is increased, namely the heat conducting area of the shell is increased, and the contact area between the capillary core layer and the inner surface of the shell is increased. Because the contact area of the capillary core layer and the inner surface of the shell is increased, the heat conduction efficiency is improved, the evaporation efficiency of the evaporator is further improved, and under the condition that the evaporation efficiency is improved, the heat dissipation efficiency of the loop heat pipe comprising the evaporator is also naturally improved.

Drawings

FIG. 1 is a cross-sectional view of one embodiment of an evaporator provided by the present disclosure;

FIG. 2 is a cross-sectional view of another embodiment of an evaporator provided by the present disclosure;

FIG. 3 is a cross-sectional view of yet another embodiment of an evaporator provided by the present disclosure;

FIG. 4 is a cross-sectional view Y-Y of FIG. 1;

FIG. 5 is a cross-sectional view Y '-Y' of FIG. 2;

FIG. 6 is a cross-sectional view Z1-Z1 of FIG. 1;

FIG. 7 is a cross-sectional view of Z2-Z2 of FIG. 1;

fig. 8 is an exploded perspective view of an evaporator provided by the present disclosure.

Detailed Description

In order to make those skilled in the art better understand the technical solution of the present disclosure, the evaporator and the loop heat pipe including the evaporator provided by the present disclosure are described in detail below with reference to the accompanying drawings.

Example embodiments will be described more fully hereinafter with reference to the accompanying drawings, but which may be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

Embodiments of the present disclosure and features of embodiments may be combined with each other without conflict.

As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the present disclosure, and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

As one aspect of the present disclosure, there is provided an evaporator, as shown in fig. 1 and 8, including a housing 100 and a capillary core layer 200, the capillary core layer 200 being disposed in the housing 100 and dividing a space in the housing 100 into a vapor collection chamber 110 and a liquid storage chamber 120, the housing 100 being formed with a vapor port 111 communicating with the vapor collection chamber 110 and a liquid return port 121 communicating with the liquid storage chamber 120. The case 100 includes a heat-conductive plate 130 for contacting an electronic device, the heat-conductive plate 130 having at least one heat-conductive rib 131 formed on an inner surface thereof, the heat-conductive rib 131 being embedded in the capillary core layer 200.

When the loop heat pipe works, a liquid working medium is arranged in the liquid storage cavity 120, and the heat conducting plate 130 is in contact with the electronic equipment and bears heat load. The capillary core layer 200 is formed with a plurality of capillary holes, under the action of capillary effect, the liquid working medium enters the capillary holes and evaporates on the surfaces of the capillary holes, the generated steam enters the steam collection cavity 110, escapes from the evaporator through the steam port 111, enters the steam pipeline connected with the steam port 111, enters the condenser through the steam pipeline, and is condensed by the condenser to form the liquid working medium. The liquid working substance enters the liquid storage chamber 120 of the evaporator through a liquid pipeline and further repeats the above cycle.

Since the heat-conducting ribs 131 are added to the heat-conducting plate 130 of the evaporator, the inner surface area of the housing 100, that is, the heat-conducting area of the housing 100, is increased, and thus the contact area between the capillary core layer 200 and the inner surface of the housing 100 is increased. Since the contact area between the capillary core layer 200 and the inner surface of the casing 100 is increased, the heat conduction efficiency is improved, and further, the evaporation efficiency of the evaporator is improved, and under the condition that the evaporation efficiency is improved, the heat dissipation efficiency of the loop heat pipe including the evaporator is also naturally improved.

It is noted that, in addition to the heat-conducting plate 130, the casing 100 further comprises a cover body 140, which cover body 141 encloses a closed casing inner space together with the heat-conducting plate 130.

In the present disclosure, the specific material of the capillary core layer 200 is not particularly limited as long as it is a porous material having capillary pores. For example, the material of the capillary core layer 200 may be a metal foam material sintered from metal powder. For example, the metal foam for forming the capillary core layer 200 may be formed by sintering metal powder such as copper powder, aluminum powder, or nickel powder.

In the present disclosure, the specific structure of the heat-conducting rib 131 is not particularly limited as long as the heat-conducting rib 131 has excellent heat-conducting performance. For example, the heat-conducting ribs 131 may be made of a metal material having a high thermal conductivity, such as copper, aluminum, or nickel. For convenience of manufacture, the heat-conducting ribs 131 may be made of the same material as the heat-conducting plate 130, and the heat-conducting plate 130 may be integrally formed with the heat-conducting ribs 131. The material of the heat-conducting ribs 31 is not a foamed metal material but a general metal. Compared with foam materials, ordinary metal materials have higher thermal conductivity. Therefore, heat can be more efficiently conducted to the capillary core layer wrapping the heat conducting ribs 131, evaporation of the liquid working medium is promoted, and evaporation efficiency is further improved.

In the present disclosure, the cross-sectional shape of the heat-conducting rib 131 is not particularly limited, and for example, as shown in fig. 1 and 2, the cross-section of the heat-conducting rib 131 may be rectangular, circular, or the like.

In the present disclosure, the specific structure of the capillary core layer 200 is not particularly limited, and as an alternative embodiment, as shown in fig. 1 to 3, the capillary core layer 200 includes a first capillary core layer 210 and a second capillary core layer 220 stacked on the first capillary core layer 210, the first capillary core layer 210 is disposed opposite to the heat conducting plate 130, and at least one vapor channel 211 is formed on the first capillary core layer 210, and an outlet of the vapor channel 211 communicates with the vapor collection chamber 110.

The steam generated on the surface of the capillary hole of the first capillary core layer 210 can rapidly enter the steam collecting cavity through the steam channel 211, so that the speed of the steam entering the condenser can be increased, and the heat dissipation efficiency is improved.

For convenience of arrangement, the length direction of the steam channel 211 coincides with the length direction of the heat conductive ribs 131.

In the present disclosure, the cross-sectional shape of the steam channel 211 is not particularly limited, and for example, the cross-section of the steam channel 211 may be circular or rectangular.

The cross-sectional area of the steam channel 211 may be provided in a rectangular shape for convenience of processing.

In order to further increase the heat transfer area and improve the evaporation efficiency, the evaporator may optionally include a plurality of heat transfer ribs 131 and a plurality of steam channels 211, and the steam channels 211 and the heat transfer ribs 131 are alternately arranged.

As described above, the capillary core layer 200 is made of a porous material, in the capillary core layer 200, the first capillary core layer 210 is disposed adjacent to the heat conducting plate 130 and serves as an evaporation capillary layer, which mainly functions to evaporate the working medium on the surface of the first capillary layer 210 to form vapor, and the second capillary core layer 220 is spaced far from the heat conducting plate 130 and serves as a transport capillary layer to transport the liquid obtained by condensation of the condenser to the liquid storage chamber 120.

In order to enable the first capillary core layer 210 to realize the evaporation function, optionally, the pore size of the first capillary core layer 210 may be smaller so as to have a larger capillary force to realize a better suction effect on the liquid working medium. In order to achieve a better transmission effect of the second capillary core layer 220, the second capillary core layer 220 may have a relatively large pore size, so as to reduce the flow resistance of the liquid working medium transmitted in the second capillary core layer, and enable the liquid working medium to obtain a higher flow rate.

That is, in the evaporator, the pore size of the second capillary core layer 220 is larger than that of the first capillary core layer 210.

In the present disclosure, the pore size of the first capillary core layer 210 and the pore size of the second capillary core layer 220 are not particularly limited, and optionally, the pore size of the first capillary core layer 210 is between 10 micrometers and 50 micrometers, and the pore size of the second capillary core layer is between 20 micrometers and 200 micrometers.

In the present disclosure, the specific structure of the first capillary core layer 210 is not particularly limited. As an alternative embodiment, as shown in fig. 6, the first capillary layer 210 includes a first body part 212 and a first channel part 213, the first channel part 213 is disposed at one side of the first body 211, the liquid storage chamber 120 is located at the other side of the first body 211, and the evaporation channel 211 is formed on the first channel part 213. It is easily understood that the heat conductive ribs 131 are embedded in the first channel part 213.

In order to further increase the speed of transferring the liquid working medium into the second capillary core layer 220, optionally, at least one auxiliary liquid supplementing channel 221 is formed in the second capillary core layer 220, an outlet of the auxiliary liquid supplementing channel 221 is communicated with the liquid storage cavity 120, the auxiliary liquid supplementing channel 221 extends from the liquid storage cavity 120 towards the vapor collecting cavity 110, and the liquid working medium in the liquid storage cavity 120 can flow into the first capillary core layer 210 in the auxiliary liquid supplementing channel 221 to form longitudinal auxiliary liquid supplementing. Since the auxiliary fluid replenishing channel 221 is located in the second capillary wick layer, the thickness of the evaporator is not increased after the auxiliary fluid replenishing channel 221 is provided. Therefore, in the evaporator provided by the present disclosure, the efficiency of liquid replenishment to the first capillary core layer 210 can be improved without increasing the thickness of the evaporator. The liquid is evaporated into vapor in the first capillary core layer, so that the evaporation efficiency of the evaporator is further improved. In addition, when the evaporator works, the evaporator is constantly under the condition of high heat flux density input, in the present disclosure, the auxiliary liquid supplementing channel 221 is arranged to improve the liquid supplementing efficiency, and the risk of dry burning of the evaporation capillary core at the far end can be effectively reduced.

In the present disclosure, specific structure of the second capillary layer 220 is not particularly limited, for example, in the specific embodiment shown in fig. 7, the second capillary layer 220 includes a second body portion 222 and a second channel portion 223, the second channel portion 223 is disposed on one side of the second body portion 222, and the vapor collection chamber 110 is located on the other side of the second body portion 222. The auxiliary fluid replenishing channel 221 is formed on the second channel portion 223.

In the present disclosure, the position of the auxiliary fluid replenishing channel 221 in the thickness direction of the second capillary layer is not particularly limited. In the embodiment shown in fig. 1 and 4, the auxiliary fluid supplement channel 221 is located at the top of the second capillary layer 220, and the auxiliary fluid supplement channel 221 has a top opening toward the housing 100, and the top opening is covered and closed by the housing 100.

Of course, the present disclosure is not limited thereto, and in the embodiments shown in fig. 2, 3, and 5, the auxiliary fluid supplement channel 221 is formed inside the second capillary layer 220.

It should be noted that when the loop heat pipe including the evaporator is operated, there will always be a portion of non-liquid working medium space in the reservoir chamber 120, and a small amount of non-condensable gas may be present in the space.

The position of the auxiliary fluid supplement channel 221 in the second capillary core layer 220 may be determined according to the specific arrangement of the heat conductive plate 130. For example, when the heat-conducting plate 130 is perpendicular to the horizontal plane during use, the auxiliary fluid-replenishing channel 210 may be disposed on top of the second capillary core layer 210, such that the fluid storage chamber 120 is located at the upper portion of the evaporator, and the working fluid can enter the auxiliary fluid-replenishing channel 221 with the aid of gravity. When the heat conducting plate 130 is parallel to the horizontal plane during use, the auxiliary fluid infusion channel 221 may be disposed in the middle of the second capillary core layer 220, so as to facilitate the drainage function of the auxiliary fluid infusion channel 221.

In the present disclosure, the cross-sectional shape of the auxiliary fluid replenishing channel 221 is not particularly limited, and for example, the cross-section of the auxiliary fluid replenishing channel 221 may be rectangular or circular.

As a second aspect of the present disclosure, a loop heat pipe is provided, where the loop heat pipe includes an evaporator, a condenser, a vapor pipeline and a liquid pipeline, one end of the vapor pipeline is communicated with a vapor port of the evaporator, and the other end of the vapor pipeline is communicated with a vapor inlet of the condenser, one end of the liquid pipeline is communicated with a liquid return port of the evaporator, and the other end of the liquid pipeline is communicated with a liquid outlet of the condenser, where the evaporator is the above-mentioned evaporator provided in the present disclosure.

As described above, when the loop heat pipe works, the liquid working medium is disposed in the liquid storage chamber 120, and the heat conducting plate 130 contacts with the electronic device to bear the heat load. The capillary core layer 200 is formed with a plurality of capillary holes, under the action of capillary effect, the liquid working medium enters the capillary holes and evaporates on the surfaces of the capillary holes, the generated steam enters the steam collection cavity 110, escapes from the evaporator through the steam port 111, enters the steam pipeline connected with the steam port 111, enters the condenser through the steam pipeline, and is condensed by the condenser to form the liquid working medium. The liquid working substance enters the liquid storage chamber 120 of the evaporator through a liquid pipeline and further repeats the above cycle.

The heat conducting ribs 131 are added to the heat conducting plate 130 of the evaporator, so that the inner surface area of the casing 100 is increased, that is, the heat conducting full area of the casing 100 is increased, and the contact area between the capillary core layer 200 and the inner surface of the casing 100 is increased. Since the contact area between the capillary core layer 200 and the inner surface of the casing 100 is increased, the heat conduction efficiency is improved, and further, the evaporation efficiency of the evaporator is improved, and under the condition that the evaporation efficiency is improved, the heat dissipation efficiency of the loop heat pipe including the evaporator is also naturally improved.

Example embodiments have been disclosed herein, and although specific terms are employed, they are used and should be interpreted in a generic and descriptive sense only and not for purposes of limitation. In some instances, features, characteristics and/or elements described in connection with a particular embodiment may be used alone or in combination with features, characteristics and/or elements described in connection with other embodiments, unless expressly stated otherwise, as would be apparent to one skilled in the art. Accordingly, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the disclosure as set forth in the appended claims.

Claims

1. The utility model provides an evaporator, the evaporator includes casing and capillary sandwich layer, capillary sandwich layer sets up in the casing, and will space division in the casing becomes collection vapour chamber and stock solution chamber, be formed with on the casing with the communicating steam port in collection vapour chamber and with the communicating liquid mouth that returns in stock solution chamber, the casing is including the heat-conducting plate that is used for contacting with electronic equipment, its characterized in that, be formed with at least one heat conduction rib on the internal surface of heat-conducting plate, the embedding of heat conduction rib is in the capillary sandwich layer.

2. The evaporator according to claim 1, wherein the capillary core layer comprises a first capillary core layer and a second capillary core layer stacked on the first capillary core layer, the first capillary core layer is disposed opposite to the heat conducting plate, and at least one vapor channel is formed on the first capillary core layer, and an outlet of the vapor channel is communicated with the vapor collection chamber.

3. An evaporator according to claim 2 wherein the length direction of the steam channel coincides with the length direction of the heat-conducting ribs.

4. An evaporator according to claim 3 wherein the evaporator comprises a plurality of heat-conducting ribs and a plurality of steam channels, the steam channels and the heat-conducting ribs being arranged alternately.

5. An evaporator according to any one of claims 2 to 4 wherein the pore size of the second capillary core layer is larger than the pore size of the first capillary core layer.

6. An evaporator according to claim 5 wherein the pore size of the first wick layer is between 10 and 50 microns and the pore size of the second wick layer is between 20 and 200 microns.

7. An evaporator according to any one of claims 2 to 4 wherein at least one auxiliary fluid replenishment passage is formed in the second capillary core layer, an outlet of the auxiliary fluid replenishment passage communicates with the reservoir chamber, and the auxiliary fluid replenishment passage extends from the reservoir chamber toward the vapor collection chamber.

8. An evaporator according to claim 7 wherein the top opening of the auxiliary replenishing channel is covered and closed by the housing.

9. The evaporator according to claim 7, wherein the auxiliary fluid replenishment passage is formed inside the second capillary core layer.

10. The utility model provides a loop heat pipe, loop heat pipe includes evaporimeter, condenser, steam line and liquid line, steam line's one end with the steam port intercommunication of evaporimeter, the other end with the steam inlet intercommunication of condenser, liquid line's one end with the liquid return mouth intercommunication of evaporimeter, the other end with the liquid outlet intercommunication of condenser, the evaporimeter be any one in claims 1 to 9 the evaporimeter.