CN212109686U

CN212109686U - Vapor-liquid flow-dividing capillary core vapor chamber heat exchanger

Info

Publication number: CN212109686U
Application number: CN202020618583.5U
Authority: CN
Inventors: 沈超群; 郭孟月; 彭权; 刘向东
Original assignee: Yangzhou University
Current assignee: Yangzhou University
Priority date: 2020-04-23
Filing date: 2020-04-23
Publication date: 2020-12-08
Anticipated expiration: 2030-04-23

Abstract

A vapor-liquid split-flow capillary core vapor chamber heat exchanger and a preparation method thereof belong to the technical field of electronic device heat dissipation, and comprise a vapor cavity, fins and a heat dissipation fan; the steam cavity is filled with the integrally sintered capillary core, the capillary core is divided into an upper layer capillary core and a lower layer capillary core, and a tree-shaped steam channel is processed in the upper layer capillary core; the phase-change working medium filled in the steam cavity absorbs heat, boils and evaporates, flows to the side wall surface and the upper wall surface of the steam cavity in the tree-shaped steam channel in the steam cavity, and is condensed for heat exchange; the other capillary core structures except the steam channel are used for pumping the condensate to flow back to the heated area to form a working cycle, the gas-phase working medium and the liquid-phase working medium in the steam cavity respectively flow in the steam channel and the capillary core, so that the mutual influence in the flowing process of the two-phase working medium is reduced, the steam is favorably diffused to the condensing surface for heat exchange, and the condensate flows back to the hot end of the heat exchanger in time. The heat exchange performance of the soaking plate heat exchanger can be effectively improved.

Description

Vapor-liquid flow-dividing capillary core vapor chamber heat exchanger

Technical Field

The utility model belongs to the technical field of the electron device heat dissipation, a capillary core vapor chamber heat exchanger is related to, specific saying so relates to one kind and has vapour-liquid reposition of redundant personnel function, has the gas-liquid two-phase flow radiator that promotes the heat transfer effect.

Background

Along with the continuous progress of science and technology, the power density of electronic devices is bigger and bigger, and in order to guarantee the reliability of devices, higher and higher requirements are put forward on the heat dissipation of electronic devices, and aiming at the heat dissipation problem of electronic devices, the current heat radiators are various in form, such as ribbed type and heat pipe type, and due to the difference of the heat transfer modes in the heat radiators, the ribbed type heat radiators are weaker in performance than the heat pipe type heat radiators. In a heat pipe type radiator, a capillary core steam cavity radiator is widely applied to heat dissipation of electrical devices due to the advantages of strong heat exchange performance and good temperature uniformity. However, under the background that the power density of electronic devices is getting larger and larger, the steam cavity radiator also faces the problem of improving the heat exchange performance. According to the working principle of the steam cavity, whether the steam can be rapidly dispersed to the condensing and exchanging surface and the condensate can rapidly and smoothly flow back to the evaporation end is an important key factor for determining the heat exchange performance of the steam cavity radiator. In the capillary core vapor chamber heat exchanger, in the working process, the working medium is heated to evaporate/boil, steam flows to the condensation exchange surface along the pores in the capillary core, and condensed liquid after condensation flows back to the heated surface along the pores under the capillary suction effect. Therefore, the steam and the condensate have the phenomenon of mutual interference, the effective distribution and flow of the steam and the condensate are influenced, and the working performance of the capillary core vapor chamber is further restricted. In order to make the vapor distribution and the condensate reflux independent from each other, reduce mutual interference and improve the performance of the capillary core vapor chamber heat exchanger, it is important to design a capillary core vapor chamber heat exchanger which can meet the performance.

SUMMERY OF THE UTILITY MODEL

The utility model aims at in the current capillary core soaking plate heat exchanger working process, the working medium is heated the evaporation boiling, steam changes the face to the condensation along the interior pore flow of capillary core, condensate after condensing flows back to the heated surface along the pore under capillary suction, steam and condensate have the phenomenon of mutual interference, influence the effective distribution and the flow of the two, restriction capillary core soaking plate's working property etc. is not enough, a capillary core soaking plate heat exchanger of vapour-liquid reposition of redundant personnel is proposed, through the capillary core structure of improving the steam intracavity, can effectively improve steam-liquid working fluid's circulation, promote heat transfer capacity.

The technical scheme of the utility model: the utility model provides a vapour-liquid reposition of redundant personnel's capillary core soaking plate heat exchanger which characterized in that: the capillary core vapor chamber heat exchanger consists of a cooling fan, cover plate fins and a steam chamber; the steam cavity comprises a steam cavity side wall and a side wall rib, a steam cavity upper cover plate, a steam cavity capillary core and a steam cavity lower cover plate, the steam cavity capillary core comprises an upper capillary core and a lower capillary core, a steam channel is processed in the upper capillary core, a gap for steam condensation is arranged between the upper capillary core and the side wall surface and the upper wall surface of the steam cavity, the lower capillary core is tightly attached to the lower wall surface of the steam cavity, a phase-change working medium is filled in the steam cavity, the capillary core vapor chamber heat exchanger is in a working process, steam and condensate in the steam cavity flow in the steam channel and the capillary core respectively, the flow resistance of the two-phase working medium is reduced, the steam flows to the condensation wall surface more smoothly, and the condensate flows back more quickly to improve the working performance of the heat exchanger.

And a gap of 0.2-0.5 mm is formed between the upper capillary core and the side wall surface and the upper wall surface of the steam cavity.

The steam cavity capillary core is formed by loose sintering of metal powder, the metal powder selects different particle sizes according to the heat exchange performance requirement, and the particle size range of the metal powder is 50-200 microns.

The steam channel is of a multi-stage branched tree structure, the steam channel is composed of steam channel main branches and steam channel branches, the steam channel main branches are distributed from the center of a steam cavity to the periphery, the steam channel branches are distributed on two sides of the steam channel main branches, the length and the depth of each stage of steam channel main branches are the same, the width of each stage of steam channel main branches and the width of the upper stage of steam channel main branches meet the Murray law, the cross sections of each stage of steam channel main branches and the steam channel branch are the same in size, and the length of each steam channel branch extends to the edge of the capillary core.

The steam cavity side wall and the side wall rib are of an integral processing structure, the steam cavity side wall and the side wall rib are respectively connected with the steam cavity upper cover plate and the steam cavity lower cover plate in a welding mode to form a closed space, and the cooling fan is fixedly connected with the cover plate fins and the side wall rib through screws.

The vapor cavity is filled with and packaged with a liquid working medium which can generate phase change after being heated.

The side wall and the upper wall of the steam cavity are subjected to hydrophobic modification treatment to strengthen steam condensation heat exchange; the bottom surface and the capillary core are subjected to hydrophilic modification treatment to strengthen the boiling heat transfer of the working medium and the suction and reflux effects of the condensate.

The steam cavity and the tree-shaped steam channel are rectangular or circular in shape, so that the applicability of the steam cavity and the tree-shaped steam channel is improved.

The utility model has the advantages that: the vapor-liquid split capillary core vapor chamber heat exchanger provided by the utility model has a simple and compact structure, and the capillary core radiator consists of a vapor chamber, fins and a radiating fan; the steam cavity is filled with an integrally sintered capillary core and is divided into an upper layer capillary core and a lower layer capillary core according to functions, wherein a tree-shaped steam channel is processed in the upper layer capillary core; radiating fins are welded on the outer side of the steam cavity and fixedly installed together with the radiating fan. The lower wall of the steam cavity is in contact with the electronic chip to take away the heat generated by the electronic chip; the phase-change working medium filled in the steam cavity absorbs heat, boils and evaporates, flows to the side wall surface and the upper wall surface of the steam cavity in the tree-shaped steam channel in the steam cavity, and is condensed for heat exchange; and other capillary core structures except the steam flow channel are used for pumping the condensate to flow back to the heated area to form a working cycle. In the working process of the vapor chamber heat exchanger, the gas-phase working medium and the liquid-phase working medium in the steam chamber respectively flow in the steam channel and the capillary core, so that the mutual influence in the flowing process of the two-phase working medium is reduced, the steam is favorably and rapidly diffused to the condensing surface for heat exchange, and the condensate is timely refluxed to the hot end of the heat exchanger. Meanwhile, the side wall and the upper wall of the steam cavity are subjected to hydrophobic modification treatment, and the bottom surface and the capillary core are subjected to hydrophilic modification treatment, so that the steam condensation, the boiling heat exchange of condensate and the quick backflow of the condensate are enhanced. Therefore, the heat exchange performance of the soaking plate heat exchanger can be effectively improved.

Drawings

Fig. 1 is a schematic view of the overall structure of the present invention.

Fig. 2 is a schematic diagram of the overall explosion structure of the present invention.

Fig. 3 is a schematic view of the working principle of the present invention.

Fig. 4 is a sectional structural view of the vapor chamber of the present invention.

Fig. 5 is a schematic view of the structure of the wick in the present invention.

Fig. 6 is a schematic view of the structure of the side wall and the side wall rib of the steam chamber of the present invention.

Fig. 7 is a schematic view of the rib structure of the middle cover plate of the present invention.

In the figure: the heat radiation device comprises a heat radiation fan 1, a cover plate rib 2, a steam cavity side wall and side wall rib 3, a steam cavity upper cover plate 4, a steam cavity capillary core 5, an upper layer capillary core 501, a bottom layer capillary core 502, a steam cavity lower cover plate 6, a heat transfer path 7, a steam flowing direction 8, a condensate backflow direction 9, cooling air 10, a steam channel main branch 1101 and a steam channel branch 1102.

Detailed Description

The present invention will be further explained with reference to the accompanying drawings:

as shown in fig. 1-2, a vapor-liquid split-flow capillary core vapor chamber heat exchanger is composed of a heat radiation fan 1, cover plate fins 2, steam chamber side walls and side wall ribs 3, a steam chamber upper cover plate 4, a steam chamber capillary core 5 and a steam chamber lower cover plate 6, in order to ensure good working performance of a heat radiator, a steam chamber shell and the fins can be made of metal materials with good heat conductivity, and particularly, in order to reduce the weight of the heat radiator, aluminum alloy materials with low density and high heat conductivity coefficient can be adopted for processing. The steam cavity is filled with a sintered capillary core, and a steam channel is processed in the capillary core. The steam cavity is filled with liquid working media such as water, acetone, alcohol, ammonia, refrigerant and the like which are heated to generate phase change, and the volume of the working media accounts for 40-60% of the effective volume of the steam cavity.

As shown in fig. 3, the operation process and principle of a vapor-liquid split-flow capillary core vapor chamber heat exchanger are as follows: heat generated in the working process of the electronic chip is transferred to the working medium dispersed in the capillary core through the lower cover plate 6 of the steam cavity according to the heat transfer path 7; the working medium is heated to evaporate/boil, the generated steam is transported to the inner wall surface (cold wall surface) of the steam cavity side wall 3 and the steam cavity upper cover plate 4 through the steam channel, and the steam is condensed into liquid condensate after the heat of the carried electronic chip is released; under the capillary suction action of the capillary core, the condensate reflows to a high-temperature area contacted with the electronic chip along the condensate reflowing direction 9 to be continuously heated, evaporated and boiled, and the heat generated by the electronic chip is taken away through circulation. The heat released by the condensation of the steam is transferred to the side wall ribs 3 and the cover plate ribs 2 through the side wall of the steam cavity and the upper cover plate, and then released to the external environment through heat exchange with the cooling air 10.

As shown in fig. 4-5, the utility model relates to a capillary core soaking plate heat exchanger suitable for radiating vapour-liquid reposition of redundant personnel of electronic chip, the sintering capillary core has been arranged to steam intracavity, adopts the sintering of loose powder dress at steam intracavity sintering capillary core 5, according to the functional differentiation, the capillary core divide into upper capillary core 501 and bottom capillary core 502. A multi-stage branched tree-shaped distributed steam channel is processed in the upper-layer capillary core 501, and comprises a steam channel main branch 1101 and a steam channel branch 1102; the steam channel main branches 1101 are distributed from the center of the steam cavity to the periphery, and the steam channel branches 1102 are distributed on two sides of the steam channel main branches 1101; the lengths and the depths of the steam channel main branches 1101 at all levels are the same, but the width of the steam channel main branches 1101 at all levels and the width of the steam channel main branches 1101 at the upper level meet the Murray law; each stage of the main branch 1101 of the steam channel is the same as the cross-sectional size of the branch 1102 of the steam channel, but the length of the branch 1102 of the steam channel extends all the way to the edge of the capillary wick. A gap with the width of 0.2-1 mm is processed between the upper-layer capillary core 501 and the side wall of the steam cavity and the upper cover plate. The bottom capillary core 502 is not processed and is paved on the bottom of the whole steam cavity, and the thickness is 0.5-2 mm. Since the upper capillary wick 501 is divided into multiple areas that are not connected by the vapor channel, the condensate cannot be directly pumped through the upper capillary wick 501 and will be close to the hot end of the electronic chip. However, the condensate can be pumped through the upper capillary wick 501 to the bottom capillary wick 502 and then pumped along the bottom capillary wick 502 to the hot end of the vapor chamber.

As shown in fig. 6-7, the vapor-liquid split capillary core soaking plate heat exchanger suitable for electronic chip heat dissipation of the present invention has the vapor chamber side wall, the side wall ribs 3 and the cover plate ribs 2 of the heat exchanger as an integral structure, and the side wall ribs 3 and the cover plate ribs 2 are opposite to each other except the vapor chamber, so as to facilitate the flow of the cold air 10. The utility model relates to a capillary core soaking plate heat exchanger suitable for radiating vapour liquid reposition of redundant personnel of electronic chip, its radiator fan passes through screw fastening connection with the apron rib.

Claims

1. The utility model provides a vapour-liquid reposition of redundant personnel's capillary core soaking plate heat exchanger which characterized in that: the capillary core vapor chamber heat exchanger consists of a cooling fan (1), cover plate fins (2) and a steam cavity; the steam chamber comprises steam chamber lateral wall and lateral wall rib (3), steam chamber upper cover plate (4), steam chamber capillary core (5) and steam chamber lower cover plate (6), steam chamber capillary core (5) comprise upper capillary core (501) and lower floor capillary core (502), processing has steam channel in upper capillary core (501), upper capillary core (501) with be equipped with the clearance that is used for steam condensation between the lateral wall face in steam chamber and the last wall face, lower floor capillary core (502) closely laminate with the lower wall face in steam chamber, it has phase transition working medium to fill in the steam chamber, capillary core soaking plate heat exchanger is in the course of the work, steam and the condensate of steam intracavity are in flow in steam channel and steam chamber capillary core (5) respectively.

2. The vapor-liquid split capillary wick heat spreader plate exchanger of claim 1, wherein: and a gap of 0.2-0.5 mm is formed between the upper capillary core (501) and the side wall surface and the upper wall surface of the steam cavity.

3. The vapor-liquid split capillary wick heat spreader plate exchanger of claim 1, wherein: the steam cavity capillary core (5) is formed by loose sintering of metal powder, and the particle size range of the metal powder is 50-200 microns.

4. The vapor-liquid split capillary wick heat spreader plate exchanger of claim 1, wherein: the steam channel is of a multi-stage branched tree structure, the steam channel is composed of steam channel main branches (1101) and steam channel branches (1102), the steam channel main branches (1101) are distributed from the center of a steam cavity to the periphery, the steam channel branches (1102) are distributed on two sides of the steam channel main branches (1101), the lengths and the depths of all stages of the steam channel main branches (1101) are the same, the width of all stages of the steam channel main branches (1101) and the width of the upper stage steam channel main branch (1101) meet the Murray law, the cross-sectional sizes of all stages of the steam channel main branches (1101) and the steam channel branches (1102) are the same, and the lengths of the steam channel branches (1102) extend to the edge of the capillary core.

5. The vapor-liquid split capillary wick heat spreader plate exchanger of claim 1, wherein: the steam cavity side wall and the side wall rib (3) are of an integral processing structure, the steam cavity side wall and the side wall rib (3) are respectively welded with the steam cavity upper cover plate (4) and the steam cavity lower cover plate (6) to form a closed space, and the cooling fan (1) is fixedly connected with the cover plate fins (2) and the side wall rib through screws.