WO2018179571A1 - Procédé de refroidissement à ébullition par immersion, dispositif de refroidissement à ébullition par immersion et appareil électronique - Google Patents

Procédé de refroidissement à ébullition par immersion, dispositif de refroidissement à ébullition par immersion et appareil électronique Download PDF

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Publication number
WO2018179571A1
WO2018179571A1 PCT/JP2017/040895 JP2017040895W WO2018179571A1 WO 2018179571 A1 WO2018179571 A1 WO 2018179571A1 JP 2017040895 W JP2017040895 W JP 2017040895W WO 2018179571 A1 WO2018179571 A1 WO 2018179571A1
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WO
WIPO (PCT)
Prior art keywords
guide
diffusion plate
circuit board
main surface
heat
Prior art date
Application number
PCT/JP2017/040895
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English (en)
Japanese (ja)
Inventor
邦彦 石原
正樹 千葉
水季 和田
Original Assignee
日本電気株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 日本電気株式会社 filed Critical 日本電気株式会社
Publication of WO2018179571A1 publication Critical patent/WO2018179571A1/fr

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F13/00—Arrangements for modifying heat-transfer, e.g. increasing, decreasing
    • F28F13/02—Arrangements for modifying heat-transfer, e.g. increasing, decreasing by influencing fluid boundary
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L23/00—Details of semiconductor or other solid state devices
    • H01L23/34—Arrangements for cooling, heating, ventilating or temperature compensation ; Temperature sensing arrangements
    • H01L23/44—Arrangements for cooling, heating, ventilating or temperature compensation ; Temperature sensing arrangements the complete device being wholly immersed in a fluid other than air
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K7/00—Constructional details common to different types of electric apparatus
    • H05K7/20—Modifications to facilitate cooling, ventilating, or heating

Definitions

  • the present invention relates to an immersion boiling cooling method, an immersion boiling cooling apparatus, and an electronic device, and more particularly, to an immersion boiling cooling method and an immersion boiling cooling in which a circuit board having a heating element is immersed and cooled in an airtight container filled with a refrigerant.
  • the present invention relates to an apparatus and an electronic device.
  • an immersion cooling method in which a circuit board having a heating element is immersed in a coolant to cool.
  • a boiling cooling method in which heat generated by the heating element is transported and radiated by a cycle of vaporization and condensation of the refrigerant.
  • Such a boiling cooling method is known to be very efficient because it cools using heat of vaporization (latent heat).
  • the refrigerant is boiled and evaporated by the heat of the heat generating element, and the heat of the heat generating element is taken away by the heat of vaporization (latent heat), thereby cooling the element.
  • the circuit board having the heating elements is arranged to stand in a container filled with the refrigerant, and a plurality of heating elements are mounted on the circuit board side by side in the vertical direction.
  • the evaporated gas of the refrigerant that has boiled on the surface of the heat generating element disposed at the lowermost stage rises directly above the heat generating element. Therefore, the boiling steam comes into contact with another heating element disposed above.
  • the surface of the heating element is surrounded by boiling steam, and the contact area between the surface of the heating element and the refrigerant is reduced. As a result, the cooling capacity may be reduced.
  • Patent Document 1 discloses a method of guiding boiling steam so as to bypass an upper heating element.
  • a guide plate is provided as a guide means between a plurality of heating elements arranged in the vertical direction, and the boiling steam is detoured to the side or the front of the heating elements. This prevents the upper heating element from being surrounded by boiling steam and prevents the cooling capacity from being lowered (see FIG. 1 of the same document).
  • Patent Document 2 discloses a technique for fixing a circuit board in such a manner that the heat generating element mounted on the circuit board faces upward and is inclined with respect to the vertical direction. Thereby, since boiling vapor rises without contacting the heating element arranged above, it can avoid that an upper heating element is surrounded by boiling steam (refer to Drawing 2 of the same literature).
  • the present invention provides an immersion boiling cooling device that can be miniaturized.
  • the immersion boiling cooling device is: An airtight container for holding a refrigerant; A heat diffusion plate including a guide, and At least a part of the main surface of the circuit board is disposed so as to stand up in the sealed container while being immersed in the refrigerant in the sealed container.
  • the circuit board includes a plurality of heating elements, The plurality of heating elements are mounted on the main surface of the circuit board side by side in the rising direction of the circuit board, The thermal diffusion plate is attached to at least one of the plurality of heating elements,
  • the guide is disposed on the heat diffusion plate, The main surface of the guide intersects with the main surface of the heat diffusing plate.
  • the electronic device is An airtight container for holding a refrigerant;
  • the circuit board includes a plurality of heating elements, The plurality of heating elements are mounted on the main surface of the circuit board side by side in the rising direction of the circuit board,
  • the thermal diffusion plate is attached to at least one of the plurality of heating elements,
  • the guide is disposed on the heat diffusion plate,
  • the main surface of the guide includes an immersion boiling cooling device that intersects the main surface of the heat diffusion plate.
  • the immersion boiling cooling method is: Attaching a heat diffusing plate including a guide to at least one of the plurality of heating elements; Aligning the rising direction of the circuit board and the direction in which the plurality of heating elements are aligned while standing up in the container while immersing at least a part of the main surface of the circuit board in a refrigerant in the container; Cooling the circuit board on which the plurality of heating elements are mounted so as to be arranged in a predetermined direction on the main surface, by immersing the circuit board in a container holding a refrigerant, and
  • the guide is disposed on the heat diffusion plate, The main surface of the guide intersects with the main surface of the heat diffusing plate.
  • FIG. 1 is a schematic cross-sectional view of an immersion boiling cooling device according to a first embodiment.
  • 1 is a schematic cross-sectional view of an immersion boiling cooling device according to a first embodiment.
  • 6 is a schematic cross-sectional view of an immersion boiling cooling device according to Embodiment 2.
  • FIG. 6 is a schematic cross-sectional view of an immersion boiling cooling device according to Embodiment 2.
  • FIGS. 1A and 1B are schematic cross-sectional views of the immersion boiling cooling device according to the first embodiment.
  • the immersion boiling cooling device 100 includes a sealed container 11, a circuit board 21, and a condenser 12.
  • the sealed container 11 holds a refrigerant 41.
  • the refrigerant 41 only needs to be a liquid that boils at a temperature lower than the heat generation temperature of the heat generating element 22 and has electrical insulation properties.
  • a fluorocarbon, hydrofluoroether, or other fluorocarbon gas can be used.
  • the sealed container 11 includes a liquid space 44 in which the refrigerant 41 is held.
  • the sealed container 11 may further include a gas space 43 filled with gas above the refrigerant 41 (in FIG. 1A and FIG. 1B, the Z-axis plus side).
  • As the gas contained in the gas space 43 a gas used in a sealed container of a known immersion boiling cooling device can be used.
  • the sealed container 11 may include a lid and an opening that can be sealed and opened as necessary.
  • the circuit board 21 has a plurality of heating elements 22 mounted thereon.
  • the circuit board 21 is disposed so as to rise inside the sealed container 11, and a plurality of heating elements 22 are mounted on the circuit board 21 side by side in this rising direction.
  • the angle formed between the main surface of the circuit board 21 and the horizontal plane may be, for example, 60 to 120 °. When the angle formed is 90 °, the sealed container 11 may be downsized. At least a part of the circuit board 21 is immersed in the refrigerant 41.
  • the heating element 22 may be an electronic element that generates heat by being supplied with a current or receiving a signal or the like as necessary.
  • the heating element 22 includes a thermal diffusion plate 31, which will be described later.
  • the condenser 12 includes a pipe that extends from the outside of the sealed container 11 to the inside, passes through the gas space 43 inside the sealed container 11, and then extends to the outside of the sealed container 11.
  • a cooling liquid introduced from the outside of the immersion boiling cooling device 100, specifically, cold water (not shown) flows through the condenser 12.
  • the condenser 12 cools and liquefies again the refrigerant 41 in a vaporized gaseous state. That is, a part of the refrigerant 41 is boiled by the heat generated in each heating element 22, and changes to the boiling vapor 42.
  • the boiling vapor 42 moves to the gas space 43 on the upper side of the sealed container 11, and then liquefies by being cooled by the condenser 12, and returns to the remaining liquid space 44 on the lower side of the sealed container 11.
  • a part of the refrigerant 41 circulates through the liquid space 44 and the gas space 43.
  • the heat generated in the heating element 22 is radiated to the outside of the sealed container 11.
  • a heat diffusion plate 31 is attached to the main surface of the heating element 22 on the circuit board 21.
  • the thermal diffusion plate 31 only needs to have higher thermal conductivity than the circuit board 21 and includes a plate-like body made of a highly thermal conductive material (also referred to as a first material).
  • a high thermal conductivity material is a metal material. Examples of such a metal material include copper, silver, aluminum, and alloys thereof.
  • the plate-like body may have various shapes, for example, a rectangular plate or a square plate.
  • the plate-like body may include a protrusion, a porous portion, and the like.
  • the heat diffusion plate 31 is attached to the surface of the heating element 22 via an adhesive, grease, or thermal sheet having high thermal conductivity.
  • the thermal conductivity of the high thermal conductivity material of the thermal diffusion plate 31 is desirably 10 W / m ⁇ K or more. Further, it is desirable that the heat diffusing plate 31 has a larger area than the heating element 22. As a result, the heat generated in the heat generating element 22 is diffused by the heat diffusion plate 31 having a surface area larger than that of the heat generating element 22, so that the heat is quickly transmitted from the heat generating element 22 to the refrigerant 41.
  • a guide 32 is disposed above the heat diffusion plate 31 so as to intersect the main surface of the heat diffusion plate 31.
  • the angle formed between the main surface of the heat diffusion plate 31 and the guide 32 is, for example, 60 to 120 °, and the lower limit of the angle may be 60, 70, 80, or 85 °, and the upper limit thereof. May be any of 95, 100, 110, and 120 °.
  • An example of the thermal diffusion plate 31 shown in FIGS. 1A and 1B is a rectangular plate.
  • a guide 32 is disposed on the upper side of the rectangular plate so as to be orthogonal to the main surface of the heat diffusion plate 31.
  • the guide 32 includes a plate-like body made of a low thermal conductivity material (also referred to as a second material).
  • This low thermal conductivity material has lower thermal conductivity than the high thermal conductivity material of the thermal diffusion plate 31.
  • this low thermal conductivity material for example, a heat insulating material such as a resin can be cited.
  • the thermal conductivity of the low thermal conductivity material of the thermal diffusion plate 31 is desirably 1 W / m ⁇ K or less.
  • the guide 32 is inclined in the horizontal plane (the XY plane in FIGS. 1A and 1B).
  • An example of the guide 32 illustrated in FIGS. 1A and 1B is inclined obliquely upward and rightward toward the paper surface.
  • the guides 32 may be inclined obliquely upward to the left toward the paper surface, or the guides 32 in the plurality of heating elements 22 may be inclined in different directions.
  • the heat generating element 22 generates heat. At least a part of the heat generated in the heat generating element 22 moves to the heat diffusion plate 31, and then the refrigerant 41 is boiled and evaporated on the surface of the heat diffusion plate 31 to generate the boiling vapor 42.
  • the boiling steam 42 tends to move right above by buoyancy. Since the example of the guide 32 shown in FIG. 1A and FIG. 1B is installed to be inclined obliquely upward to the right toward the paper surface, the boiling steam 42 is guided to the upper right by the example of the guide 32 and then It moves to the gas space 43.
  • the heat diffusing plate 31 having the guide 32 is installed in each heating element 22 arranged in the vertical direction, the boiling vapor 42 generated in each heating element 22 is higher than the generated heating element 22.
  • the heater element 22 is not touched and moves upward around the right side. Accordingly, it is possible to avoid the upper heating element 22 from being surrounded by the boiling vapor 42, and to reliably cool each heating element 22.
  • the guide 32 is preferably formed using a heat insulating material such as a resin, but may be formed using a metal material, or may be integrally formed using the same material as the heat diffusion plate 31. Good.
  • a heat insulating material such as a resin
  • the guide 32 is integrally formed using the same material as that of the heat diffusion plate 31, the heat generated in the heating element 22 is transmitted to the guide 32, whereby boiling steam 42 is also generated from the guide 32.
  • the guide 32 since most of the boiling vapor 42 is generated from the heat diffusion plate 31 and guided to the upper right by the guide 32, it is possible to avoid the upper heating element 22 from being completely surrounded by the boiling vapor 42.
  • the guide 32 is formed using a heat insulating material, the heat generated in the heating element 22 is not easily transmitted to the guide 32, and the boiling vapor 42 is not easily generated from the guide 32. Substantially all of the boiling vapor 42 is generated from the heat diffusion plate 31 and is guided to the upper right by the guide 32. Therefore, the surrounding of the upper heating element 22 by the boiling steam 42 can be avoided more reliably.
  • the guide 32 is attached to a heat diffusion plate 31 attached to each heating element 22. For this reason, it is not necessary to arrange the guide 32 between the heat generating elements 22 on the circuit board 21.
  • the circuit board 21 is mounted with high density of the heating elements 22 or parts including the heating elements 22. For example, even when the heating elements 22 are adjacent to each other, the guide 32 and the heat diffusion plate 31 can be attached to the circuit board 21. it can. For this reason, the immersion boiling cooling device 100 can be reduced in size.
  • the heat diffusing plate 31 has a larger area than the heat generating element 22, the heat generated by the heat generating element 22 is diffused by the heat diffusing plate 31 having a large surface area. Therefore, heat is quickly transmitted from the heating element 22 to the refrigerant 41.
  • FIGS. 2A and 2B are schematic cross-sectional views of the immersion boiling cooling device according to the second embodiment.
  • the immersion boiling cooling device 200 includes a heat diffusion plate 31 having a guide 32, similar to the immersion boiling cooling device 100 (see FIGS. 1A and 1B).
  • a heat diffusion plate 31 having a guide 32, similar to the immersion boiling cooling device 100 (see FIGS. 1A and 1B).
  • the heating element 22 is not attached with an inclination.
  • the heat generating element 22 generates heat. At least a part of the heat generated in the heat generating element 22 moves to the heat diffusion plate 31, and then the refrigerant 41 is boiled and evaporated on the surface of the heat diffusion plate 31 to generate the boiling vapor 42.
  • the boiling steam 42 tends to move right above by buoyancy. Since the example of the guide 32 shown in FIG. 2A and FIG. 2B is installed substantially horizontally toward the paper surface, the boiling steam 42 is divided into the right or the left according to the example of the guide 32, and is respectively above the guide 32. After being guided, it moves to the upper gas space 43.
  • the heat diffusing plate 31 having the guide 32 is installed in each heating element 22 arranged side by side in the vertical direction, the boiling vapor 42 is brought into contact with the heating element 22 above the generated heating element 22. Instead, it detours on the right or left side and moves upward. Accordingly, it is possible to avoid the upper heating element 22 from being surrounded by the boiling vapor 42, and to reliably cool each heating element 22.
  • the guide 32 is formed using a heat insulating material, the heat generated in the heating element 22 is not easily transmitted to the guide 32, and the boiling vapor 42 is not easily generated from the guide 32. Substantially all of the boiling steam 42 is generated from the heat diffusion plate 31, divided right or left by the guide 32, and guided to the upper side of the guide 32. Therefore, the surrounding of the upper heating element 22 by the boiling steam 42 can be avoided more reliably.
  • the guide 32 is attached to the heat diffusion plate 31 attached to each heating element 22, as in the immersion boiling cooling device 100. For this reason, it is not necessary to arrange the guide 32 between the heat generating elements 22 on the circuit board 21. That is, even if the circuit board 21 is mounted with the heat generating element 22 or a component including the same at a high density, the guide 32 and the heat diffusion plate 31 can be attached to the circuit board 21. Therefore, the size of the immersion boiling cooling device 200 can be reduced.
  • the immersion boiling cooling devices 100 and 200 when used, it is possible to avoid the upper heating element 22 from being surrounded by the boiling vapor 42 of the refrigerant 41 and to reliably cool the heating element 22. It becomes. In addition, it is possible to reduce the size of the immersion boiling cooling devices 100 and 200 themselves.
  • the immersion boiling cooling devices 100 and 200 may be used by being incorporated in various electronic devices having a portion that generates heat. Such an electronic device is preferable because the cooling performance and downsizing of the immersion boiling cooling devices 100 and 200 can be achieved, so that more reliable thermal control and downsizing of the size can be achieved.
  • an immersion boiling cooling method for cooling a plurality of heating elements using the immersion boiling cooling devices 100 and 200.
  • the circuit board 21 on which the plurality of heating elements 22 are mounted so as to be arranged in a predetermined direction on the main surface is cooled by immersing it in the sealed container 11 holding the refrigerant 41.
  • the sealed container 11 includes a lid and an opening that can be sealed and opened as necessary.
  • the heat diffusing plate 31 including the guide 32 is attached to at least one of the plurality of heating elements 22 (heat diffusing plate attaching step S1).
  • the guide 32 is disposed on the heat diffusion plate 31.
  • the main surface of the guide 32 intersects the main surface of the heat diffusing plate 31.
  • circuit board placement step S2 At least a part of the main surface of the circuit board 21 is raised in the opened sealed container 11 while being immersed in the refrigerant 41 in the sealed container 11 in the opened state. Further, the direction in which the plurality of heating elements 22 are arranged on the circuit board 21 is made to coincide with the direction in which the circuit board 21 rises (circuit board placement step S2).
  • the circuit board 21 when the circuit board 21 is operated to cause the heat generating element 22 to generate heat, the refrigerant 41 is boiled and evaporated on the surface of the thermal diffusion plate 31 to generate the boiling vapor 42 as in the case of the immersion boiling cooling devices 100 and 200.
  • the heating element 22 above the generated heating element 22 is not brought into contact. Accordingly, it is possible to avoid the upper heating element 22 from being surrounded by the boiling vapor 42, and to reliably cool each heating element 22.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Computer Hardware Design (AREA)
  • Power Engineering (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Cooling Or The Like Of Semiconductors Or Solid State Devices (AREA)
  • Cooling Or The Like Of Electrical Apparatus (AREA)

Abstract

La présente invention concerne des dispositifs de refroidissement à ébullition par immersion (100, 200) comprenant : un récipient étanche (11) qui contient un réfrigérant (41) ; et une plaque de diffusion thermique (31) comprenant un guide (32). Au moins une partie de la surface principale d'une carte de circuit imprimé (21) est disposée de façon à s'élever sur le récipient étanche (11) tout en étant immergée dans le réfrigérant (41) dans le récipient étanche (11). La carte de circuit imprimé (21) comprend une pluralité d'éléments chauffants (22) montés sur celle-ci, les éléments chauffants étant disposés sur la surface principale de la carte de circuit imprimé (21) en parallèle avec la direction dans laquelle la carte de circuit imprimé (21) s'élève. La plaque de diffusion thermique (31) est fixée à au moins un élément chauffant de la pluralité d'éléments chauffants (22), le guide (32) est disposé dans une partie supérieure de la plaque de diffusion thermique (31), et la surface principale du guide (32) croise la surface principale de la plaque de diffusion thermique (31). Une miniaturisation peut, par exemple, être ainsi obtenue.
PCT/JP2017/040895 2017-03-31 2017-11-14 Procédé de refroidissement à ébullition par immersion, dispositif de refroidissement à ébullition par immersion et appareil électronique WO2018179571A1 (fr)

Applications Claiming Priority (2)

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JP2017-070501 2017-03-31
JP2017070501 2017-03-31

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WO2018179571A1 true WO2018179571A1 (fr) 2018-10-04

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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61176141A (ja) * 1985-01-31 1986-08-07 Fujitsu Ltd 固体集積回路部品の冷却装置
JPH0162732U (fr) * 1987-10-15 1989-04-21
US20160234970A1 (en) * 2013-02-01 2016-08-11 Dell Products, L.P. Partitioned, Rotating Condenser Units to Enable Servicing of Submerged IT Equipment Positioned Beneath a Vapor Condenser Without Interrupting a Vaporization-Condensation Cycling of the Remaining Immersion Cooling System

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61176141A (ja) * 1985-01-31 1986-08-07 Fujitsu Ltd 固体集積回路部品の冷却装置
JPH0162732U (fr) * 1987-10-15 1989-04-21
US20160234970A1 (en) * 2013-02-01 2016-08-11 Dell Products, L.P. Partitioned, Rotating Condenser Units to Enable Servicing of Submerged IT Equipment Positioned Beneath a Vapor Condenser Without Interrupting a Vaporization-Condensation Cycling of the Remaining Immersion Cooling System

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