Liquid immersion cooling unit, liquid immersion cooling system, and container system

Abstract

This liquid immersion cooling unit comprises: a casing which has a housing space extending in a first direction and capable of housing a first refrigerant, and in which a heating element extending in the first direction is disposed in the housing space; and a heat pipe which has an evaporation part that, in the casing, extends in the first direction and opposes the heating element in an opposite direction intersecting the first direction, and which has a condensation part having a heat dissipation surface facing outside the casing, a second refrigerant circulating between the evaporation part and the condensation part.

Description

Liquid Immersion Cooling Unit, Liquid Immersion Cooling System, and Container System

[0001] The present disclosure relates to a liquid immersion cooling unit, a liquid immersion cooling system, and a container system. This application claims priority to Japanese Patent Application No. 2024-166237 filed in Japan on September 25, 2024, the content of which is incorporated herein by reference.

[0002] Patent Document 1 discloses an electronic device having a plurality of computer units and a rack that houses these units. Inside the computer unit, a cooling plate that contacts an element as a heat generating body and a heat pipe that contacts the cooling plate are provided. The rack is provided with a thermal contact portion that receives heat from the heat pipe.

[0003] Japanese Patent Application Laid-Open No. 2009-271643

[0004] By the way, in recent years, with the improvement in the performance of elements such as CPUs and GPUs, the amount of heat generated by these elements has been increasing. Therefore, in data centers and the like where these elements are intensively arranged, it is required to cool the elements more efficiently. Also, it is necessary to establish an efficient cooling method for heat generating bodies that are intensively arranged, not limited to these elements.

[0005] The present disclosure provides a liquid immersion cooling unit, a liquid immersion cooling system, and a container system that can improve cooling efficiency.

[0006] The liquid immersion cooling unit according to the present disclosure has a housing that extends in a first direction and has an accommodation space capable of accommodating a first refrigerant, and a heat generating body that extends in the first direction is arranged in the accommodation space. The liquid immersion cooling unit also has an evaporation portion that faces the heat generating body in a facing direction that intersects the first direction and extends in the first direction inside the casing, and a condensation portion that has a heat dissipation surface facing outside the casing. The liquid immersion cooling unit further has a heat pipe in which a second refrigerant circulates between the evaporation portion and the condensation portion.

[0007] The liquid immersion cooling system according to this disclosure comprises the above-mentioned liquid immersion cooling unit and a cooling rack for housing the liquid immersion cooling unit, wherein the cooling rack has a rack body having a plurality of housing sections R capable of housing each of the liquid immersion cooling units, and a cooling section that exchanges heat with the condensing section by contacting the heat dissipation surface of each of the liquid immersion cooling units housed in the housing space.

[0008] The container system according to this disclosure comprises the above-mentioned immersion cooling system, a container body housing the immersion cooling system, a heat exchanger provided inside the container body for exchanging heat between a third refrigerant flowing through the cooling section and air, and a blower provided inside the container body for discharging air introduced outside the container body to the outside of the container after passing it through the heat exchanger.

[0009] The immersion cooling unit, immersion cooling system, and container system of this disclosure can improve cooling efficiency.

[0010] This is a schematic diagram showing the general configuration of a container system according to the first embodiment of this disclosure. This is a schematic diagram showing the general configuration of an immersion cooling system provided in a container system according to the first embodiment of this disclosure. This is a perspective view of an immersion cooling unit according to the first embodiment of this disclosure. This is a longitudinal cross-sectional view showing the detailed structure of an immersion cooling unit according to the first embodiment of this disclosure. This is a longitudinal cross-sectional view showing the detailed structure of an immersion cooling unit according to the second embodiment of this disclosure.

[0011] <First Embodiment> (Configuration of Container System) Hereinafter, an example of applying the immersion cooling system having the immersion cooling unit according to the first embodiment of this disclosure to a container system will be described with reference to Figures 1 to 4. The container system 1 shown in Figure 1 is a so-called container-type data center. The container system 1 includes a container body 2, a heat exchanger 3, a fan 4, and an immersion cooling unit 40.

[0012] (Container body) The container body 2 is a hollow rectangular parallelepiped. An air inlet 2a is formed on a part of the side of the container body 2, penetrating the container body 2 inward and outward. Multiple air outlets 2b are formed on the top surface of the container body 2, penetrating the container body 2 inward and outward.

[0013] (Heat exchanger) The heat exchanger 3 is installed in the space inside the container body 2. For example, a fin tube type can be used as the heat exchanger 3. The heat exchanger 3 may be positioned so as to block the air inlet 2a, so that all the air passing through the air inlet 2a passes through the heat exchanger 3.

[0014] The fan 4 is located in the upper part of the container body 2, directly below the air outlet 2b. The fan 4 is positioned to correspond to each air outlet 2b. The fan 4 rotates around an axis extending vertically. As the fan 4 rotates, air is introduced into the container body 2 from outside through the air outlet 2b. This air passes through the heat exchanger 3 and is then discharged upwards through the air outlet 2b. In this embodiment, the air blowing unit 5 is composed of the air inlet 2a, the fan 4, and the air outlet 2b.

[0015] (Configuration of the immersion cooling system) The immersion cooling system 10 is installed inside the container body 2. As shown in Figure 2, the immersion cooling system 10 has a cooling rack 20 and an immersion cooling unit 40.

[0016] (Cooling Rack) The cooling rack 20 houses a plurality of liquid immersion cooling units 40 and has the function of cooling these liquid immersion cooling units 40. The cooling rack 20 has a rack body 21, a partition 22, an opening / closing part 25, and a cooling device 30. The cooling device 30 is provided on one side of the rack body 21 in the first direction D1, which is one horizontal direction (right side in Figure 2).

[0017] (Rack body) The rack body 21 is box-shaped with an opening across the entire area on the other side (left side in Figure 2) of the first horizontal direction D1. The opening extends in the second horizontal direction D2, which is perpendicular to the first horizontal direction D1, with the second direction D2 being the width direction. The opening extends across the entire vertical direction D3 of the cooling rack 20.

[0018] (Partition) The partition 22 is a plate-shaped member that extends horizontally. Multiple partitions 22 are arranged within the rack body 21 at intervals in the vertical direction D3. Multiple storage compartments R are partitioned within the rack body 21 by these multiple partitions 22. The multiple storage compartments R are arranged in the vertical direction D3. Each storage compartment R opens to the other side of the first direction D1 of the rack body 21. The dimensions of the storage compartments R are smaller in the vertical direction D3 compared to the dimensions in the first direction D1 and the second direction D2. That is, the storage compartments R are thin spaces in the vertical direction D3.

[0019] (Opening / Closing Section) The opening / closing section 25 is provided to open and close the opening of the rack body 21. The opening / closing section 25 is provided to be rotatable, for example, around an axis extending in the vertical direction D3 relative to the rack body 21. As a result, the opening / closing section 25 is displaceable between a closed position that closes the opening of the rack body 21 and an open position that opens the opening of the rack body 21, allowing an operator to access the inside of the rack body 21.

[0020] (Cooling device) The cooling device 30 has a plurality of cooling units 31 and a refrigerant line 32. The plurality of cooling units 31 are arranged on one side of the rack body 21 in the first direction D1 with spacing in the vertical direction D3. Each cooling unit 31 is provided to correspond to a plurality of storage units R in a one-to-one relationship. Each cooling unit 31 is in the shape of a block made of a metal such as copper or aluminum, which has high thermal conductivity.

[0021] The surface of each cooling unit 31 facing the other side of the first direction D1 is a cooling surface 31a that is planar and extends in the second direction D2 and the vertical direction D3. The cooling surface 31a is positioned to face into the housing unit R from one end of the housing unit R on one side of the first direction D1. That is, at least a part of the end of the housing unit R on one side of the first direction D1 is open horizontally, and the cooling surface 31a of the cooling unit 31 faces into the housing unit R through this opening. Here, as shown in Figures 2 and 4, the cooling surface 31a is flush with the inner surface (Ra) of the end of the housing unit R on one side of the first direction D1, and is configured to form a part of the inner surface Ra of the end. Although detailed illustrations are omitted, the cooling unit 31 may be configured so that its cooling surface 31a is located on the inside side of the housing unit R relative to the inner surface Ra of the end. In this case, the cooling unit 31 is provided penetrating the inner surface Ra that, together with the partition 22, divides the housing unit R. Furthermore, the cooling surface 31a may be configured to face the inside of the housing R while being located outside the housing R, relative to the inner surface Ra of the end portion.

[0022] A cooling channel 31b is formed within the cooling section 31 through which the refrigerant can flow. The refrigerant is supplied from the outside into the cooling channel 31b. The refrigerant that has flowed through the cooling channel 31b is discharged to the outside. The cooling section 31 itself is cooled by the flow of the refrigerant within it.

[0023] The refrigerant line 32 is connected to the internal flow path 31b within the cooling section 31 (see Figure 4). The refrigerant line 32 has a refrigerant supply pipe 32a and a refrigerant discharge pipe 32b. The refrigerant supply pipe 32a branches into multiple pipes at one end within the cooling device 30 and is connected to the inlet of the internal flow path 31b in each cooling section 31. The refrigerant discharge pipe 32b branches into multiple pipes at one end within the cooling device 30 and is connected to the outlet of the internal flow path 31b in each cooling section 31. The other ends of the refrigerant supply pipe 32a and the refrigerant discharge pipe 32b extend from below the cooling device 30 to the outside and are connected to the tubes of the heat exchanger 3, as shown in Figure 1. This configures the refrigerant to circulate within the heat exchanger 3, the refrigerant line 32, and the cooling section 31.

[0024] (Liquid Immersion Cooling Unit) Next, the detailed configuration of the liquid immersion cooling unit 40 will be described. Multiple liquid immersion cooling units 40 are provided. Each liquid immersion cooling unit 40 is housed in a one-to-one relationship within each housing R in the rack body 21 of the cooling rack 20. The liquid immersion cooling unit 40 has a casing 50, a heating element 60, and a heat pipe 70, as shown in detail in Figures 3 and 4.

[0025] (Casing) The casing 50 has a top plate 52, a bottom plate 51, side plates 53, a front plate 54, and a back plate 55. The casing 50 is a hollow rectangular parallelepiped. The bottom plate 51 forms the bottom surface of the casing 50. The bottom plate 51 is a rectangular flat plate that extends in a first direction D1 and a second direction D2 along the horizontal plane. The upper surface of the bottom plate 51 is the first opposing surface 51a.

[0026] The top plate 52 forms the top surface of the casing 50. Like the bottom plate 51, the top plate 52 is a rectangular flat plate that extends in a first direction D1 and a second direction D2 along the horizontal plane. The top plate 52 is provided above the bottom plate 51 with a gap between them. That is, the bottom plate 51 and the top plate 52 face each other in the vertical direction D3. In the liquid used in this implementation, the vertical direction D3 is the direction of opposition. The lower surface of the top plate 52 is the second opposing surface 52a.

[0027] The side panels 53 are plate-shaped and extend in the first direction D1 and the vertical direction D3. A pair of side panels 53 are provided so as to connect the side edges on both sides of the bottom panel 51 and the top panel 52 in the second direction D2 to each other in the vertical direction D3. The front panel 54 are plate-shaped and extend in the second direction D2 and the vertical direction D3. The front panel 54 are provided so as to connect the side edges on the other side of the first direction D1 of the bottom panel 51 and the top panel 52 to each other in the vertical direction D3. The rear panel 55 are plate-shaped and extend in the second direction D2 and the vertical direction D3. The rear panel 55 are provided so as to connect the side edges on one side of the first direction D1 of the bottom panel 51 and the top panel 52 to each other in the vertical direction D3.

[0028] A rectangular prism-shaped storage space is formed inside the casing 50 by the six plates described above. The vertical dimension D3 of the casing 50 and the storage space is smaller than the dimensions in the first direction D1 and the second direction D2. That is, the casing 50 and the storage space are thin in the vertical direction D3 and flattened in the horizontal direction, including the first direction D1 and the second direction D2.

[0029] (Heating element) The heating element 60 is provided in the lower (one side in the opposing direction D3) region of the housing space of the casing 50. The heating element 60 is provided on the first opposing surface 51a. The heating element 60 is, for example, a semiconductor substrate on which a CPU or GPU is mounted. The heating element 60 may have a configuration in which the semiconductor substrate and the heat sink are integrated into one structure. The heating element 60 is a flat plate shape that extends outward in the first direction D1 and the second direction D2. The bottom surface 60a of the heating element 60, which is the surface facing downward (one side in the third direction), is fixed on the first opposing surface 51a so as to extend over most of the first opposing surface 51a. Here, as shown in Figure 4, the first opposing surface 51a and the bottom surface 60a may be in direct contact with each other, or they may be fixed via a spacer or the like so that they face each other with a gap between them.

[0030] The heating element 60 is provided with a unit-side connector 61 that protrudes from the heating element 60 to one side in the first direction D1. The unit-side connector 61 penetrates the back plate 55 of the casing 50 in the first direction D1 and protrudes from the casing 50 to one side in the first direction D1. When the immersion cooling unit 40 is housed in the housing R of the cooling rack 20, the unit-side connector 61 is electrically connected to a rack-side connector 35 provided on the cooling device 30 of the cooling rack 20. The semiconductor substrate constituting the heating element 60 is electrically connected to external equipment via the unit-side connector 61 and the rack-side connector 35.

[0031] (Heat pipe) The heat pipe 70 is arranged both inside and outside the casing 50 so as to penetrate a portion of the casing 50 in an airtight and liquid-tight manner. The heat pipe 70 consists of an evaporation section 80 and a condensation section 90.

[0032] (Evaporation section) The evaporation section 80 is located in the area above the housing space of the casing 50 (on the opposite side in the opposing direction D3). The evaporation section 80 is located in the housing space and is positioned above and opposite to the heating element 60. The evaporation section 80 is thin in the vertical direction D3 and has a flat plate shape that extends horizontally, including the first direction D1 and the second direction D2. That is, the dimension of the evaporation section 80 in the vertical direction D3 is shorter than that in the first direction D1 and the second direction D2.

[0033] The first outer surface 81 of the evaporation section 80, which faces downward, and the main surface 60b of the heating element 60, which faces upward, face each other in the vertical direction D3. The first outer surface 81 of the evaporation section 80 and the main surface 60b of the heating element 60 have the same rectangular shape when viewed from the vertical direction D3, and face each other in the vertical direction D3 across their entire surfaces. That is, the dimension of the first outer surface 81 of the evaporation section 80 in the first direction D1 is the same as the dimension of the main surface 60b of the heating element 60 in the first direction D1, and the dimension of the first outer surface 81 of the evaporation section 80 in the second direction D2 is the same as the dimension of the main surface 60b of the heating element 60 in the second direction D2. The second outer surface 82 of the evaporation section 80, which faces upward, faces the second opposing surface 52a of the top plate 52 of the casing 50 with a gap in the vertical direction D3.

[0034] (Condensing section) The condensing section 90 is provided on one side of the casing 50 in the first direction D1. The condensing section 90 is thin in the first direction D1 of the casing 50 and has a flat plate shape that extends in the second direction D2 and the vertical direction D3. The dimensions of the condensing section 90 in the second direction D2 and the vertical direction D3 are larger than those of the casing 50.

[0035] The surface of the condensing section 90 facing the other side in the first direction D1 is the adjacent surface 91 of the back plate 55 of the casing 50 viewed from the other side in the first direction D1. The adjacent surface 91 is integrally fixed to the back plate 55 of the casing 50. The adjacent surface 91 has a planar shape extending in the second direction D2 and the vertical direction D3.

[0036] The surface opposite to the adjacent surface 91 in the condensing section 90 is a heat dissipation surface 92 facing one side in the first direction D1. The heat dissipation surface 92 is planar in shape and extends in the second direction D2 and the vertical direction D3. When the immersion cooling unit 40 is housed in the housing section R, the heat dissipation surface 92 is in contact with the cooling surface 31a of the cooling section 31 of the cooling device 30 from the other side in the first direction D1.

[0037] Here, one end of the evaporation section 80 on the first direction D1 side is integrally connected to the upper part of the condensation section 90 by penetrating the back plate 55 of the casing 50 in the first direction D1. As a result, the heat pipe 70 as a whole is L-shaped when viewed from the second direction D2. A sealing member may be provided at the point where the heat pipe 70 penetrates the casing 50 to seal the housing space airtight and liquidtight with respect to the external space of the casing 50.

[0038] An internal flow path 70a (schematically shown in Figure 4) is formed inside the heat pipe 70, extending from the evaporation section 80 to the condensation section 90. The internal flow path 70a in the evaporation section 80 extends, for example, in a meandering manner so as to span the entire area of ​​the evaporation section 80 when viewed from the vertical direction D3. The internal flow path 70a in the condensation section 90 extends, for example, in a meandering manner so as to span the entire area of ​​the condensation section 90 when viewed from the first direction D1. The refrigerant sealed in the internal flow path circulates through the internal flow path, causing the refrigerant to circulate between the evaporation section 80 and the condensation section 90.

[0039] (First refrigerant, second refrigerant, and third refrigerant) Here, the first refrigerant C1 is contained within the containment space of the casing 50. In this embodiment, the first refrigerant C1 is contained to such an extent that the entire heating element 60 is immersed in the first refrigerant C1. The evaporation section 80 is positioned above the liquid phase of the first refrigerant C1, that is, it is provided in a state where it is immersed in the first refrigerant C1.

[0040] The internal flow path 70a of the heat pipe 70 is filled with a second refrigerant C2. The second refrigerant C2 circulates through the evaporation section 80 and the condensation section 90 according to the internal flow path 70a.

[0041] In the refrigerant line 32 of the cooling device 30 and the internal flow path 31b of the cooling section, a third refrigerant C3 is enclosed. The third refrigerant C3 circulates between the cooling section 31 and the heat exchanger 3 by, for example, a pump (not shown) provided on the refrigerant line 32. As a result, the third refrigerant C3 cooled by exhausting heat in the heat exchanger 3 is sequentially introduced into the cooling section 31. The third refrigerant C3 heated by flowing through the cooling section 31 is sent back to the heat exchanger again to exhaust heat.

[0042] As the first refrigerant C1, the second refrigerant C2, and the third refrigerant C3, for example, water or various organic solvents can be used. As the first refrigerant C1, the second refrigerant C2, and the third refrigerant C3, the same kind of refrigerant may be used, or different kinds of refrigerants may be used.

[0043] (Function and Effect) Next, the function and effect of the container system 1 having the above configuration will be described. Each immersion cooling unit 40 is inserted from the other side to the one side in the first direction D of the accommodation part R of the rack main body 21 in a state where the opening / closing part 25 of the cooling rack 20 is open. When the immersion cooling unit 40 is inserted into the accommodation part R, the heat radiating surface 92 of the condensation part 90 abuts on the cooling surface 31a of the cooling section 31. Also, the unit-side connector 61 of the immersion cooling unit 40 and the rack-side connector 35 of the cooling rack 20 are electrically connected. Therefore, without performing extra work, the immersion cooling unit 40 can be made in a state where it can be cooled, and the CPU, GPU, etc. of the heat generating body 60 can be made in an operable state.

[0044] In each immersion cooling unit 40, when the heat generating body 60 generates heat as the element operates, heat is supplied from the heat generating body 60 to the first refrigerant C1, the heat generating body 60 is cooled, and the temperature of the first refrigerant C1 rises. As a result, a part of the first refrigerant C1 evaporates and becomes a gas phase, and contacts the entire outer surface of the evaporation part 80 provided above the heat generating body 60. At this time, heat exchange occurs between the gas-phase first refrigerant C1 and the second refrigerant C2 in the evaporation part 80. As a result, the first refrigerant C1 becomes a liquid phase, and the second refrigerant C2 in the evaporation part 80 is heated and evaporates.

[0045] The first refrigerant C1, now in the liquid phase, is dripped in and merges with the first refrigerant C1 into which the heating element 60 is immersed. That is, the first refrigerant C1 circulates between the heating element 60 and the evaporation section 80 while undergoing a phase change. Meanwhile, the second refrigerant C2, now in the gas phase within the evaporation section 80, moves into the condensation section 90. As the heat dissipation surface 92 of the condensation section 90 is in contact with the cooling surface 31a of the cooling section 31, the heat from the gaseous second refrigerant C2 in the condensation section 90 is dissipated to the third refrigerant C3 in the cooling section 31 via these heat dissipation surfaces 92 and 31a. As a result, the second refrigerant C2 in the condensation section 90 is cooled and returns to a liquid state from the gaseous phase. The liquid second refrigerant C2 is then sent back to the evaporation section 80. In this way, the second refrigerant C2 repeatedly circulates between the evaporation section 80 and the condensation section 90, dissipating the heat generated by the heating element 60 of the immersion cooling unit 40 to the cooling section 31.

[0046] As described above, according to this embodiment, by employing liquid immersion cooling in which the heating element 60 is immersed in the first refrigerant C1 within the casing 50, the heat generated by the heating element 60 can be efficiently removed. That is, since heat can be removed from the entire heating element 60 by the first refrigerant C1, it is possible to cool the entire heating element 60 more efficiently compared to, for example, the case where the heat pipe 70 is in direct contact with a part of the heating element 60.

[0047] In this embodiment, the heating element 60 and the evaporation section 80, which extend in a flat plate shape in the first direction D1 and the second direction D2 respectively, face each other. That is, the heating element 60 and the evaporation section 80 are in a state where they face each other while each having a two-dimensional extent. Therefore, a large surface area can be secured between the heating element 60 and the evaporation section 80. In addition, since the liquid immersion cooling unit 40 has a thin configuration in the vertical direction D3, the heating element 60 and the evaporation section 80 are positioned in close proximity to each other. Therefore, the first refrigerant C1, which has become a gas on the main surface 60b of the heating element 60, moves upward and then quickly comes into contact with the outer surface of the evaporation section 80. As a result, heat can be transferred quickly from the heating element 60 to the evaporation section 80 over a wide area, making it possible to improve cooling efficiency.

[0048] In addition, in the present embodiment, since the thin liquid immersion cooling units 40 can be stacked in the vertical direction D3, a plurality of liquid immersion cooling units 40 can be intensively arranged. Thereby, the space efficiency can be improved.

[0049] Furthermore, since the heat radiating surface 92 of the condensing unit 90 extends in the second direction D2 and the vertical direction D3, a large heat radiating surface 92 area can be ensured. Particularly in the present embodiment, the dimensions of the condensing unit 90 in the second direction D2 and the vertical direction D3 are set large with respect to the casing 50. Thereby, the area of the heat radiating surface 92 can be further ensured.

[0050] And since the heat radiating surface 92 of the condensing unit 90 faces the side opposite to the casing 50, it is possible to avoid the heat of the heat radiating surface 92 being transmitted to the casing 50. Further, since the cooling unit 31 is provided on the side opposite to the casing 50 with the condensing unit 90 interposed therebetween, the cooling unit 31 itself does not invade the accommodation space. Therefore, a large size of the accommodation portion R in the casing 50 can be ensured.

[0051] Also, the heat exchange location between the cooling unit 31 (low temperature portion) and the condensing unit 90 (high temperature portion) is not an integral structure, but heat exchange occurs through the contact surface. Therefore, for example, even if one heating element 60 fails, it is easy to replace the heating element 60 without stopping the operation of the entire system.

[0052] <Second Embodiment> Next, a second embodiment of the liquid immersion cooling system of the present invention will be described with reference to FIG. 5. In FIG. 5, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted. In the second embodiment, the configuration of the cooling unit 31 of the cooling device 30 and the configuration of the heat pipe 100 of the liquid immersion cooling unit 40 are different from those in the first embodiment.

[0053] That is, the cooling section 31 of the cooling device 30 in the second embodiment protrudes from one side in the first direction D1 to the other side within the housing section R of the rack body 21. The cooling section 31 is a flat plate shape that extends in both the first direction D1 and the second direction D2 within the housing section R and is thin in the vertical direction D3. The entire downward-facing surface of the cooling section 31 is the cooling surface 31a. The flow path 31b within this cooling section extends, for example, in a meandering manner within the cooling section 31 when viewed from the vertical direction D3, so as to reach the entire first direction D1 and the second direction D2.

[0054] The evaporation section 80 of the heat pipe 100 is a flat plate shape that expands in the first direction D1 and the second direction D2 within the casing 50 and is thinned in the vertical direction D3, similar to the first embodiment. The condensation section 90 of the heat pipe 100 is located above and outside the casing 50. The condensation section 90 is a flat plate shape that expands in the first direction D1 and the second direction D2 and is thinned in the vertical direction D3. The downward-facing surface of the condensation section 90 is an adjacent surface 91 that is spaced apart above the top plate 52 of the casing 50. In this embodiment, the adjacent surface 91 is spaced apart from the top plate 52 of the casing 50. The upward-facing surface of the condensation section 90 is a heat dissipation surface 92 that contacts the cooling surface 31a of the cooling section 31 over its entire surface.

[0055] The evaporation section 80 and the condensation section 90 are connected via a connecting section 110. The connecting section 110 is provided so as to penetrate vertically through the bottom plate 51 of the casing 50. The lower end of the connecting section 110 is connected to one end of the evaporation section 80 in the first direction D1, and the upper end of the connecting section 110 is connected to one end of the condensation section 90 in the first direction D1. The dimension of the connecting section 110 in the first direction D1 is equivalent to the dimension of the evaporation section 80 and the condensation section 90 in the vertical direction D3. The dimension of the connecting section 110 in the second direction D2 is equivalent to the dimension of the evaporation section 80 and the condensation section 90 in the second direction D2. The connecting section 110 penetrates the inside and outside of the casing 50 in an airtight and liquid-tight manner. As in the first embodiment, a sealing member or the like may be provided at the penetration.

[0056] The internal flow path 70a of the heat pipe 100 extends across the evaporation section 80, the connection section 110, and the condensation section 90, and the second refrigerant C2 flowing through the internal flow path 70a is configured to circulate between the evaporation section 80 and the condensation section 90. The internal flow path 70a within the evaporation section 80 and the condensation section 90 extends, for example, in a meandering manner when viewed from the first direction D1, and is spread throughout the entire area of ​​the evaporation section 80 and the condensation section 90.

[0057] With the configuration of the second embodiment described above, the heat from the heat-generating element 60 can be effectively removed in the same manner as in the first embodiment. Furthermore, the area of ​​the heat-dissipating surface 92 in the evaporation section 80 can be made larger than in the first embodiment. As a result, the heat from the heat-generating element 60 can be removed even more efficiently, and the cooling efficiency can be further improved.

[0058] Furthermore, by positioning the evaporation section 80 above the condensation section 90, the natural circulation of the second refrigerant C2 flowing through the internal flow path 70a of the heat pipes 70 and 100 can be promoted. That is, the second refrigerant C2 that has become a gas in the evaporation section 80 can be quickly sent to the condensation section 90, while the second refrigerant C2 that has become a liquid in the condensation section 90 can be quickly sent to the evaporation section 80. This further improves the cooling efficiency.

[0059] <Other Embodiments> Although embodiments of this disclosure have been described in detail above with reference to the drawings, the specific configuration is not limited to these embodiments and may include design changes and the like that do not depart from the gist of this disclosure.

[0060] In the first and second embodiments, the heating element 60 and the evaporation section 80 are configured as flat plates extending in the first direction D1 and the second direction D2, but the invention is not limited to these configurations. For example, the heating element 60 and the evaporation section 80 may be configured as rods extending only in the first direction D1. Even in this case, since the directions in which the heating element 60 and the evaporation section 80 extend coincide, a large area of ​​contact between the heating element 60 and the evaporation section 80 can be secured. Therefore, the cooling efficiency can be improved. Furthermore, the internal flow path 70a configured inside the evaporation section 80 may be made of refrigerant pipes, and the evaporation section 80 may be formed as a flat plate extending in the first direction D1 and the second direction D2, or as a rod extending only in the first direction D1, by arranging, bundling, or bending these refrigerant pipes.

[0061] In the first and second embodiments, an example was described in which the heating element 60 is placed in the lower region of the housing space within the casing 50 and the evaporation section 80 is placed in the upper region. However, the invention is not limited to this, and the heating element 60 may be placed in the upper region of the housing space within the casing 50 and the evaporation section 80 in the lower region. In this case, in the second embodiment, the connecting portion 110 penetrates the bottom plate 51 of the casing 50 vertically, and the condensing section 90 may be placed below the bottom plate 51 of the casing 50. In this case, the cooling portion 31 protruding into the housing section R of the rack body 21 is placed so as to contact the condensing section 90 from below.

[0062] Furthermore, in this embodiment, the direction in which the heating element 60 and the evaporation section 80 face each other is set to the vertical direction D3, but this is not the only option. The facing direction may also be set to the horizontal direction. This allows for the configuration of a liquid immersion cooling system 10 in which thin liquid immersion cooling units 40 are arranged in the horizontal direction. In this case as well, the arrangement efficiency of the liquid immersion cooling units 40 can be improved, similar to the embodiment.

[0063] Furthermore, the internal flow path 70a and the internal flow path 31b of the cooling section may be configured such that the flow directions of the second refrigerant C2 circulating in the condensing section 90 of the heat pipes 70 and 100 and the third refrigerant C3 circulating in the cooling section 31 are opposite to each other, creating a counterflow. This improves the heat exchange efficiency between the two.

[0064] Furthermore, the top plate 52 of the casing 50 may be provided with a hole for supplying refrigerant and a plug to close the hole. The bottom plate 51 of the casing 50 may be provided with a hole for discharging refrigerant and a plug to close the hole.

[0065] Furthermore, the heat dissipation surface 92 and the cooling surface 31a may each have an uneven structure. These uneven structures may be configured to fit together. This increases the contact area between the heat dissipation surface 92 and the cooling surface 31a.

[0066] In the second embodiment, grooves may be formed on the heat dissipation surface 92 and the cooling surface 31a so as to extend in the direction of insertion of the immersion cooling unit 40 into the housing R. These grooves may be configured to fit together. This makes it possible to increase the contact area between the heat dissipation surface 92 and the cooling surface 31a while improving the insertability of the immersion cooling unit 40.

[0067] The internal flow path 70a of the heat pipes 70 and 100 may be provided with a backflow prevention valve to prevent backflow of the second refrigerant C2.

[0068] The shape of the internal flow path 70a is not limited to a meandering shape, and various shapes can be adopted. The internal flow path 70a in the evaporation section 80 may be configured so that the arrangement density is higher in the part facing the area of ​​the heat-generating element 60 where heat generation is particularly high.

[0069] When the immersion cooling unit 40 is housed in the housing section R, it may be detachably fixed to the rack body 21 via, for example, magnets or an engagement mechanism. Furthermore, although not shown in the figures, the immersion cooling unit 40 may be supported or guided by rails that extend in the first direction D1 and limit displacement relative to the rack body 21, thereby being housed in the housing section R of the rack body 21. This makes it easier for workers to insert and remove the immersion cooling unit 40, even when it has become heavier due to the inclusion of the first refrigerant C1.

[0070] In this embodiment, an example of applying the immersion cooling system 10 to a container system 1 has been described, but it may also be applied to other systems. The heat-generating element 60 is not limited to elements that make up a semiconductor substrate, but other heat-generating components may be used. <Note> The immersion cooling unit 40 described in each embodiment can be understood, for example, as follows.

[0071] (1) The liquid immersion cooling unit 40 according to the first embodiment includes a casing 50 that extends in a first direction D1 and has a housing space capable of housing a first refrigerant C1, and in the housing space a heating element 60 extending in the first direction D1 is arranged; and a heat pipe 70, 100 that has an evaporation section 80 that faces the heating element 60 in a counter direction D3 intersecting the first direction D1 and extends in the first direction D1, and a condensation section 90 that has a heat dissipation surface 92 facing outside the casing 50, and in which a second refrigerant C2 circulates between the evaporation section 80 and the condensation section 90.

[0072] The heat generated by the heat-generating element 60 is transferred to the evaporation section 80 via the first refrigerant C1. Furthermore, since the heat-generating element 60 and the evaporation section 80 are facing each other within the casing 50, both extending in the first direction D1, a large facing area can be secured. This improves cooling efficiency.

[0073] (2) The liquid immersion cooling unit 40 of the second embodiment is the liquid immersion cooling unit 40 of (1), wherein the housing space extends in a second direction D2 that intersects both the first direction D1 and the opposing direction, and the heating element 60 and the evaporation section 80 extend in the first direction D1 and the second direction D2.

[0074] With the above configuration, a large surface area can be secured between the heat-generating element 60 and the evaporation section 80, further improving cooling efficiency.

[0075] (3) The third embodiment of the immersion cooling unit 40 is the immersion cooling unit 40 of (1) or (2), wherein the dimensions of the housing space in the opposing directions are shorter than the dimensions of the first direction D1 and the second direction D2.

[0076] With the above configuration, the heat-generating element 60 and the evaporation unit 80 are placed in close proximity within the containment space, thereby further increasing the cooling efficiency. Furthermore, the casing 50 can be made thinner in the opposing direction. As a result, space efficiency can be improved.

[0077] (4) The fourth embodiment of the immersion cooling unit 40 is any of the immersion cooling units 40 of (1) to (3), wherein the condensing section 90 is provided on one side of the casing 50 in the first direction D1, and the heat dissipation surface 92 faces the other side of the first direction D1.

[0078] With the above configuration, the heat dissipation surface 92 faces the outside of the casing 50, which improves the heat dissipation efficiency of the heat pipe 70.

[0079] (5) The fifth embodiment of the immersion cooling unit 40 is the immersion cooling unit 40 of (1) to (3), wherein the condensing portion 90 is provided on one side of the casing 50 in the first direction D1, the heat dissipation surface 92 faces the one side of the first direction D1, and the condensing portion 90 and the heat dissipation surface 92 extend in the longitudinal direction of the second direction D2.

[0080] With the above configuration, the heat dissipation surface 92 faces outside the casing 50, which improves the heat dissipation efficiency of the heat pipe 70. In addition, the area of ​​the heat dissipation surface 92 can be made larger, further improving the cooling efficiency.

[0081] (6) The sixth embodiment of the immersion cooling unit 40 is any of the immersion cooling units 40 of (1) to (3), wherein the heating element 60 is provided on one side of the opposing direction D3 within the housing space, the evaporation section 80 is provided on the other side of the opposing direction D3 within the housing space, the condensing section 90 is provided on the other side of the opposing direction D3 of the casing 50, and the heat dissipation surface 92 faces one side of the opposing direction D3.

[0082] With the above configuration, the heat dissipation surface 92 faces outside the casing 50, which improves the heat dissipation efficiency of the heat pipe 100. It also ensures a sufficient surface area for heat dissipation.

[0083] (7) The seventh embodiment of the immersion cooling unit 40 is any of the immersion cooling units 40 of (1) to (6), wherein the heating element 60 is provided on one side of the opposing direction D3 within the housing space, the evaporation section 80 is provided on the other side of the opposing direction D3 within the housing space, the condensing section 90 is provided on the other side of the opposing direction D3 of the casing 50, the heat dissipation surface 92 faces the other side of the opposing direction D3, and the condensing section 90 and the heat dissipation surface 92 extend planarly in the first direction D1 and the second direction D2.

[0084] With the above configuration, the heat dissipation surface 92 faces outside the casing 50, thereby improving the heat dissipation efficiency of the heat pipe 100. Furthermore, the area of ​​the heat dissipation surface 92 can be increased, further improving the cooling efficiency.

[0085] (8) The eighth embodiment of the immersion cooling system 10 comprises an immersion cooling unit 40 of any of (1) to (7) and a cooling rack 20 for housing the immersion cooling units 40, wherein the cooling rack 20 has a rack body 21 having a plurality of housing spaces capable of housing each of the immersion cooling units 40, and a cooling unit 31 that exchanges heat with the condensing unit 90 by contacting the heat dissipation surface 92 of each of the immersion cooling units 40 housed in the housing space.

[0086] According to the above configuration, multiple immersion cooling units 40 can be centrally arranged while efficiently cooling the heat-generating elements 60 of each immersion cooling unit 40.

[0087] (9) The 9th embodiment of the immersion cooling system 10 is the immersion cooling system 10 of (8), wherein the plurality of housings R are arranged such that the immersion cooling units 40 are arranged in the opposing direction D3.

[0088] With the above configuration, if the immersion cooling unit 40 is thin in the opposing direction D3, multiple immersion cooling units 40 can be arranged more intensively, thereby improving space efficiency.

[0089] (10) The liquid immersion cooling system 10 according to the tenth embodiment is the liquid immersion cooling system 10 of (9), wherein the opposing direction D3 is the vertical direction D3.

[0090] According to the above configuration, the efficiency of arranging the liquid immersion cooling units 40 in the vertical direction D3 can be improved. Furthermore, in each liquid immersion cooling unit 40, if the heat-generating element 60 is positioned at the bottom and the evaporation section 80 is positioned at the top, the circulation of the first refrigerant C1 in the containment space can be promoted.

[0091] (11) The container system 1 according to the eleventh embodiment comprises a liquid immersion cooling system 10 according to any of (8) to (10), a container body 2 that houses the liquid immersion cooling system 10, a heat exchanger 3 provided inside the container body 2 for exchanging heat between a third refrigerant C3 flowing through the cooling section 31 and air, and a blower 5 provided inside the container body 2 for introducing air from outside the container body 2 into the container body 2, passing it through the heat exchanger 3, and discharging it outside the container body 2.

[0092] According to the above configuration, the cooling efficiency of the heat-generating element 60 in the container system 1 can be improved.

[0093] The immersion cooling unit, immersion cooling system, and container system of this disclosure can improve cooling efficiency.

[0094] 1 Container system 2 Container body 2a Air inlet 2b Air outlet 3 Heat exchanger 4 Fan 5 Blower 10 Liquid immersion cooling system 20 Cooling rack 21 Rack body 22 Partition 25 Opening / closing part 30 Cooling device 31 Cooling section 31a Cooling surface 31b Internal flow path of cooling section 32 Refrigerant line 32a Refrigerant supply pipe 32b Refrigerant discharge pipe 35 Rack side connector 40 Liquid immersion cooling unit 50 Casing 51 Bottom plate 51a First opposing surface 52 Top plate 52a Second opposing surface 53 Side plate 54 Front plate 55 Back plate 60 Heating element 60a Bottom surface 60b Main surface 61 Unit side connector 70 Heat pipe 70a Internal flow path 80 Evaporation section 81 First outer surface 82 Second outer surface 90 Condensing section 91 Adjacent surface 92 Heat dissipation surface 100 Heat pipe 110 Connection section R Housing section C1 First refrigerant C2 Second refrigerant C3 Third refrigerant D1 First direction D2 Second direction D3 Up and down direction (opposing direction)

Claims

1. A liquid immersion cooling unit comprising: a casing having a containment space that extends in a first direction and is capable of containing a first refrigerant, wherein a heating element extending in the first direction is disposed in the containment space; and a heat pipe having an evaporation section that faces the heating element in a direction intersecting the first direction and extends in the first direction within the casing, and a condensation section having a heat dissipation surface facing outside the casing, wherein a second refrigerant circulates between the evaporation section and the condensation section.

2. The immersion cooling unit according to claim 1, wherein the containment space extends in a second direction intersecting both the first direction and the opposing direction, and the heating element and the evaporation section extend in the first direction and the second direction.

3. The immersion cooling unit according to claim 2, wherein the dimensions of the housing space in the opposing direction are shorter than the dimensions in the first and second directions.

4. The condensing section is provided on one side of the casing in the first direction, and the heat dissipation surface faces the one side in the first direction, as described in claim 1.

5. The liquid immersion cooling unit according to claim 3, wherein the heating element is provided on one side in the opposing direction within the containment space, the evaporation section is provided on the other side in the opposing direction within the containment space, the condensation section is provided on the other side in the first direction outside the casing, the heat dissipation surface faces the other side in the first direction, and the condensation section and the heat dissipation surface extend with the second direction as the longitudinal direction.

6. The immersion cooling unit according to claim 1, wherein the heating element is provided on one side in the opposing direction within the containment space, the evaporation section is provided on the other side in the opposing direction within the containment space, the condensation section is provided on the other side in the first direction outside the casing, and the condensation section is provided on the other side in the opposing direction of the casing, and the heat dissipation surface faces one side in the opposing direction.

7. The condensing portion is provided on one side of the casing in the opposing direction, the heat dissipation surface faces the one side in the opposing direction, and the condensing portion and the heat dissipation surface extend in the first direction and the second direction, respectively, in the liquid immersion cooling unit according to claim 3.

8. A liquid immersion cooling system comprising: a liquid immersion cooling unit according to any one of claims 1 to 7; and a cooling rack for housing the liquid immersion cooling unit, wherein the cooling rack comprises: a rack body having a plurality of housing sections capable of housing each of the liquid immersion cooling units; and a cooling section that exchanges heat with the condensing section by contacting the heat dissipation surface of each of the liquid immersion cooling units housed in the housing space.

9. The liquid immersion cooling system according to claim 8, wherein the plurality of housings are arranged such that the liquid immersion cooling units are arranged in the opposing direction.

10. The liquid immersion cooling system according to claim 9, wherein the opposing direction is the vertical direction, and the evaporation section is provided above the heating element.

11. A container system comprising: an immersion cooling system according to claim 8; a container body housing the immersion cooling system; a heat exchanger provided inside the container body for exchanging heat between a third refrigerant flowing through the cooling section and air; and a blower provided inside the container body for discharging air introduced outside the container body to the outside of the container body after passing it through the heat exchanger.

Images