Cooling plate, immersion tank and server system

Abstract

A cooling plate, immersion tank, and server system are presented. The cooling plate includes a fluid inlet port, a cooling enclosure, and an inlet channel, where the inlet channel is coupled between the fluid inlet port and the cooling enclosure to direct two-phase fluid entering from the inlet port into the cooling enclosure. The cooling enclosure includes a plurality of heat sink structures coupled to an inner surface of the cooling enclosure to form a gap, where contact of the two-phase fluid with the heat sink structures causes a portion of the two-phase fluid to become vapor-phase two-phase fluid. The cooling plate includes an expanded vapor channel coupled to the cooling enclosure for collecting the vapor-phase two-phase fluid. The cooling plate includes a vapor outlet port coupled to the expanded vapor channel for expelling the vapor-phase two-phase fluid out of the vapor outlet port, where the cooling plate is immersible into an immersion tank containing a single-phase immersion fluid.

Description

TECHNICAL FIELD

[0001] The present disclosure relates generally to server and data center cooling. More specifically, the present disclosure relates to a cooling plate, immersion tank, and server system. BACKGROUND

[0002] For a data center that includes several active electronic racks, its thermal management is critical to ensure proper performance (e.g., performing IT services) of servers and / or other IT equipment running in the racks. However, without proper thermal management, the thermal environment (e.g., temperature) within the racks can exceed the thermal operating threshold, resulting in undesirable consequences (e.g., server failure, etc.). One way to manage the thermal environment is to cool the IT equipment using cooling air. The cooling air is recirculated through a cooling unit. The heat generated by the IT equipment is captured by the cooling air and extracted by the cooling unit.

[0003] In recent years, data centers have been deploying high power density electronic racks, in which a large number of high-density chips are packed together to provide higher computing power. Cooling these high-density racks by maintaining a proper thermal environment is a problem that exists in cooling systems (e.g., Computer Room Air Conditioning (CRAC) units). For example, while a CRAC unit can maintain the thermal environment for more conventional (or lower density) racks, the CRAC unit cannot effectively cool the high power density racks because the higher density electronic devices in the high power density racks generate heat load at a higher rate. Alternatively, upgrading the CRAC system to meet the cooling needs of high-density deployments requires a significant cost. Another challenge of air cooling high-density racks is moving a large amount of air flow sufficient to cool the racks. Since the heat dissipation capacity of fluid is much greater than that of air, moving a cooling fluid to cool is more economical. Therefore, it is an effective means to design the cooling fluid to be closer to the IT equipment, indirectly or directly in contact with the electronic devices. SUMMARY

[0004] According to an aspect of the disclosure, a cooling plate is provided. The cooling plate includes a fluid inlet port, a cooling enclosure thermally coupled to server electronics for accelerated cooling, an inlet channel coupled between the fluid inlet port and the cooling enclosure to direct two-phase fluid entering from the inlet port into the cooling enclosure, wherein the cooling enclosure includes a plurality of heat spreading structures coupled to an inner surface of the cooling enclosure to form a plurality of spaces between the plurality of heat spreading structures, wherein the plurality of spaces increase a surface contact area between the two-phase fluid and the plurality of heat spreading structures that can be accommodated in the cooling enclosure to distribute heat from the plurality of heat spreading structures to the two-phase fluid to cause at least a portion of the two-phase fluid to become vapor-phase two-phase fluid, an expanded vapor channel coupled to the cooling enclosure for collecting the vapor-phase two-phase fluid, and a vapor outlet port coupled to the expanded vapor channel for expelling the vapor-phase two-phase fluid out of the cooling plate.

[0005] According to another aspect of the disclosure, there is provided a submersion tank for an electronic device. The submersion tank includes a submersion housing; a distribution manifold coupled to the submersion housing, the distribution manifold including at least one fluid supply device connector, and at least one vapor return device connector; and at least one cooling plate located below the at least one fluid supply device connector and the at least one vapor return device connector, wherein each of the at least one cooling plate includes a fluid inlet port coupled to a fluid supply device connector for receiving a two-phase fluid; a cooling housing thermally coupled to a server electronic device for accelerated cooling; an inlet channel coupled between the fluid inlet port and the cooling housing for directing the two-phase fluid entering from the inlet port into the cooling housing, wherein the cooling housing includes a plurality of heat spreading structures coupled to an inner surface of the cooling housing to form a plurality of spaces between the plurality of heat spreading structures, wherein the plurality of spaces increase a surface contact area between the two-phase fluid and the plurality of heat spreading structures that can be accommodated in the cooling housing to distribute heat from the plurality of heat spreading structures to the two-phase fluid to cause at least a portion of the two-phase fluid to become a vapor-phase two-phase fluid; an expanded vapor channel coupled to the cooling housing for collecting the vapor-phase two-phase fluid; and a vapor outlet port coupled between the expanded vapor channel and a vapor return device connector for returning the vapor-phase two-phase fluid from the expanded vapor channel to the vapor return device connector, wherein the cooling plate is submersed in the submersion tank containing a single-phase submersion fluid.

[0006] According to another aspect of the disclosure, a server system is provided. The server system comprises: a server housing having server electronics housed therein; at least one server inlet port; at least one server outlet port; at least one inlet extensible line coupled to the at least one server inlet port; at least one outlet extensible line coupled to the at least one server outlet port; and a cooling plate comprising: a fluid inlet port coupled to the at least one inlet extensible line for receiving a two-phase fluid from the at least one server inlet port; a cooling housing thermally coupled to a portion of the server electronics for accelerated cooling; an inlet channel coupled between the fluid inlet port and the cooling housing for directing the two-phase fluid entering from the inlet port into the cooling housing, wherein the cooling housing comprises: a plurality of heat spreading structures coupled to an inner surface of the cooling housing to form a plurality of spaces between the plurality of heat spreading structures, wherein the plurality of spaces increase a surface contact area between the two-phase fluid and the plurality of heat spreading structures that can be housed in the cooling housing to distribute heat from the plurality of heat spreading structures to the two-phase fluid to cause at least a portion of the two-phase fluid to become a vapor phase two-phase fluid; an expanded vapor channel coupled to the cooling housing for collecting the vapor phase two-phase fluid; and a vapor outlet port coupled between the expanded vapor channel and the at least one outlet extensible line for returning the vapor phase two-phase fluid from the expanded vapor channel to the at least one server outlet port, wherein the cooling plate is immersible in an immersion tank containing a single-phase fluid.

[0007] This summary provides only a general overview of some features and advantages of embodiments of the disclosure; however, other features, advantages, and embodiments can be provided, or will be apparent from the disclosure, drawings, specification, and claims, to those skilled in the art. Accordingly, it should be understood that the scope of the disclosure should not be limited by the particular embodiments disclosed in this summary. BRIEF DESCRIPTION OF DRAWINGS

[0008] Embodiments of the disclosure are explained in terms of exemplary, non-limiting embodiments in the drawings, wherein like reference numerals designate similar elements throughout the several views, and wherein:

[0009] Figure 1 A block diagram of an immersion cooling plate is shown according to an embodiment;

[0010] Figure 2 A block diagram of an immersion server system utilizing local accelerated cooling is shown according to an embodiment;

[0011] Figure 3 A block diagram of an immersion system utilizing single phase fluid and two phase fluid for local accelerated cooling is shown in accordance with an embodiment;

[0012] Figure 4 A front view of an immersion system with one or more servers utilizing local accelerated cooling is shown in accordance with an embodiment; and

[0013] Figure 5 A side view of an immersion system with one or more servers utilizing local accelerated cooling is shown in accordance with an embodiment. DETAILED DESCRIPTION

[0014] Various embodiments and aspects of the disclosure will be described with reference to details discussed below, and illustrated in the accompanying drawings. The following description and drawings are illustrative of the disclosure and are not to be construed as limiting the disclosure. Numerous specific details are described to provide a thorough understanding of various embodiments of the present disclosure. However, in certain instances, well known or conventional details are not described in order to provide a concise discussion of embodiments of the present disclosure.

[0015] References in the specification to "one embodiment" or "an embodiment" mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the disclosure. The appearances of the phrase "in one embodiment" in various places in the specification are not necessarily all referring to the same embodiment.

[0016] Immersion cooling involves submerging electronic devices at least partially in a non-conductive dielectric solution, which is a viable solution for high density electronic devices. Immersion cooling solutions only consider fluid recirculation for electronic racks and do not consider local accelerated cooling. Heterogeneous electronic components can create predictable hotspots under immersion cooling.

[0017] Generally, liquid cooling solutions are developed primarily using either single-phase fluid cooling solutions or using two-phase fluid cooling solutions. Embodiments of the present disclosure provide an immersion system for server electronics that uses a hybrid of single-phase fluid and two-phase fluid. The single-phase fluid can be used for immersion cooling, and the two-phase fluid can be used for local accelerated cooling to mitigate hotspots. Two-phase fluid refers to a liquid coolant that provides cooling to an electronic device when the electronic device is in thermal contact with the liquid coolant during cooling by undergoing a phase change from a liquid phase to a vapor phase. Single-phase fluid also refers to a liquid coolant that is selected to provide cooling to an electronic device by passing the single-phase fluid through a thermal conductor of the electronic device, such as by thermal conduction, to cool the electronic device without undergoing a phase change. In this way, a localized thermal accelerator in an immersion environment can be provided.

[0018] According to a first aspect, a cooling plate includes a fluid inlet port, a cooling housing, and an inlet channel, wherein the inlet channel is coupled between the fluid inlet port and the cooling housing to direct two-phase fluid entering from the inlet port into the cooling housing. The cooling housing includes a plurality of heat sink structures coupled to an inner surface of the cooling housing to form a plurality of spaces between the plurality of heat sink structures, wherein the plurality of spaces increases a surface contact area between the two-phase fluid and the plurality of heat sink structures that can be contained in the cooling housing to distribute heat from the plurality of heat sink structures to the two-phase fluid to cause a portion of the two-phase fluid to become vapor-phase two-phase fluid. The cooling plate includes an expanded vapor channel coupled to the cooling housing for collecting the vapor-phase two-phase fluid. The cooling plate includes a vapor outlet port coupled to the expanded vapor channel for expelling the vapor-phase two-phase fluid out of the cooling plate. Wherein the cooling plate can be immersed in an immersion tank containing single-phase immersion fluid. The two-phase fluid provides local cooling to mitigate hotspots in immersion cooling, which also enables an increase in power density for the immersed electronic device.

[0019] In an embodiment, the cooling housing or the heat sink structures include copper or aluminum metal. In an embodiment, the spaces between the heat sink structures form fluid channels along a length direction of the heat sink structures.

[0020] In an embodiment, the cooling housing has an inner region containing the two-phase fluid, and the cooling housing separates the single-phase fluid surrounding the cooling housing from the two-phase fluid contained in the cooling housing.

[0021] In an embodiment, the fluid inlet port is connected to a two-phase liquid supply, and the vapor outlet port is connected to a vapor return of the immersion tank.

[0022] For example, in an embodiment, with reference to Figure 1 andFigure 2 In this design, a set of additional loop lines 215 and 217 are required, the ends of which are packaged with ports / connectors 205 and 207 in order to be connected to external sources, wherein the set of loop lines are connected to port 105 and port 107. In another embodiment, port 107 and port 105 can be assembled to the housing 101 through flexible hoses, and port 105 and port 107 can be expanded by expanding the flexible hoses as shown in Figure 3

[0023] In an embodiment, the expanded vapor channel includes an intermediate holding area for the two-phase fluid in vapor phase before being delivered to the vapor outlet port.

[0024] In an embodiment, the expanded vapor channel can be immersed in a single-phase fluid to exchange heat between the single-phase fluid and the two-phase fluid in vapor phase contained in the expanded vapor channel, thereby condensing part of the two-phase fluid in vapor phase into a two-phase fluid in liquid phase, wherein the two-phase fluid in liquid phase is directly returned to the interior region of the cooling housing.

[0025] In an embodiment, the fluid flow of the single-phase immersion fluid is separated from the fluid flow of the two-phase fluid in the interior region of the cooling housing. In an embodiment, the heat dissipation structure is assembled or directly made on the cooling housing. In an embodiment, the surface of the cooling housing is in contact with the chip or any other electronic device packaged on the server to provide two-phase thermal cooling to the chip.

[0026] In an embodiment, the vapor outlet port and the fluid inlet port are located on the same side of the cooling housing or on different sides of the cooling housing. If the vapor outlet port and the fluid inlet port are located on the same side, the cooling plate can be placed so that the ports face the top of the immersion tank. In this case, the two-phase cooling fluid can enter the cooling plate through the fluid inlet port using gravity. When the two-phase cooling fluid evaporates, the vapor can effectively rise from the cooling plate in a passive manner through the pressure change in the interior region of the cooling plate.

[0027] ​According to a second aspect, a soak tank for electronic devices includes a soak enclosure and a distribution manifold, wherein the distribution manifold is coupled to the soak enclosure. The distribution manifold includes at least one fluid supply device connector and at least one vapor return device connector, wherein at least one cooling plate is disposed below the at least one fluid supply device connector and the at least one vapor return device connector. The cooling plate includes a fluid inlet port, a cooling enclosure, and an inlet channel, wherein the inlet channel is coupled between the fluid inlet port and the cooling enclosure to direct two-phase fluid entering from the inlet port into the cooling enclosure. The cooling enclosure includes a plurality of heat spreading structures coupled to an inner surface of the cooling enclosure to form a plurality of spaces between the plurality of heat spreading structures, wherein the plurality of spaces increase a surface contact area between the two-phase fluid and the plurality of heat spreading structures that can be contained in the cooling enclosure to distribute heat from the plurality of heat spreading structures to the two-phase fluid to cause a portion of the two-phase fluid to become vapor phase two-phase fluid. The cooling plate includes an expanded vapor channel coupled to the cooling enclosure for collecting the vapor phase two-phase fluid. The cooling plate includes a vapor outlet port coupled to the expanded vapor channel for expelling the vapor phase two-phase fluid out of the vapor outlet port. Wherein the cooling plate is submersible in the soak tank containing a single phase soak fluid. The two-phase fluid provides local cooling to mitigate hot spots in single phase soak cooling, and the local cooling also enables an increase in power density for the submersed electronic devices.

[0028] According to a third aspect, an immersion server system comprises: a server housing having server electronics housed therein; at least one server inlet port; at least one server outlet port; at least one inlet extensible line coupled to the at least one server inlet port; at least one outlet extensible line coupled to the at least one server outlet port; and at least one cooling plate comprising a fluid inlet port, a cooling housing, and an inlet channel, wherein the fluid inlet port is coupled to the at least one inlet extensible line to receive two-phase fluid from the at least one server inlet port, the cooling housing is thermally coupled to a portion of the server electronics for accelerated cooling, and the inlet channel is coupled between the fluid inlet port and the cooling housing to direct two-phase fluid entering from the inlet port into the cooling housing. The cooling housing comprises a plurality of heat spreading structures coupled to an inner surface of the cooling housing to form a plurality of spaces between the plurality of heat spreading structures, wherein the plurality of spaces increases a surface contact area between the two-phase fluid and the plurality of heat spreading structures that can be housed in the cooling housing to distribute heat from the plurality of heat spreading structures to the two-phase fluid to cause a portion of the two-phase fluid to become vapor-phase two-phase fluid. An expansion vapor channel is coupled to the cooling housing for collecting the vapor-phase two-phase fluid. A vapor outlet port is coupled between the expansion vapor channel and the at least one outlet extensible line to return the vapor-phase two-phase fluid from the expansion vapor channel to the at least one server outlet port. The cooling plate is immersible in an immersion tank containing single-phase immersion fluid.

[0029] Figure 1 A block diagram of an immersion cooling plate (or cooling plate) 100 is shown, according to an embodiment. The cooling plate 100 is designed to be immersed in an immersion fluid and directly coupled to a high power density chip to provide local accelerated cooling to the high power density chip.

[0030] In one embodiment, the cold plate 100 includes a housing 101 that forms an interior region and is designed as a containment for two-phase coolant fluid contained in the housing 101 and separated from single-phase coolant surrounding the housing 101. In one embodiment, the housing 101 includes one or more heat spreading structures (or fins) 103 located on the interior side of the housing 101. The fins 103 can increase the interior surface area of the two-phase fluid that can be contained in the housing 101 in thermal contact with the housing 101 to expand the effective heat transfer area of the housing 101. As the two-phase coolant fills in the interior region, heat transferred from the thermally coupled electronic devices causes the two-phase coolant fluid to evaporate from a liquid to a vapor. The phase change of the two-phase coolant fluid serves to thermally cool the electronic devices. In one embodiment, the housing 101 and / or the fins 103 can be made of copper and / or aluminum metal. In one embodiment, the fins 103 are assembled or directly fabricated on the housing 101.

[0031] In one embodiment, the cold plate 100 includes an inlet port 105 and an outlet port 107, where the inlet port 105 and the outlet port 107 are located on the same side of the housing 101. The inlet port 105 can be connected to a two-phase liquid supply line of an electronic rack to supply cooling fluid, such as two-phase cooling fluid, in the cold plate 100. The outlet port 107 can be connected to a vapor return line of the electronic rack to return vapor, such as vapor phase two-phase cooling fluid. In another embodiment, the inlet port 105 and the outlet port 107 are located on different sides of the housing 101. In one embodiment, the inlet port 105 and the outlet port 107 are secured to the housing 101 of the cold plate 100. As shown, additional loop lines with inlet / outlet ports can be coupled to the inlet port 105 and the outlet port 107. Figure 2 In some embodiments, the inlet port 105 and the outlet port 107 are expandable, where, as shown, the inlet port 105 and the outlet port 107 are expanded to couple to a distribution manifold of an immersion tank. Figure 3 In some embodiments, the inlet port 105 and the outlet port 107 are expandable, where, as shown, the inlet port 105 and the outlet port 107 are expanded to couple to a distribution manifold of an immersion tank.

[0032] In one embodiment, the fins 103 form flow channels (or gaps) 111 that can be aligned with the inlet port 105 to facilitate fluid flow within the housing 101. In one embodiment, the height of the fins 103 can be about half the height of the interior region of the housing 101. In one embodiment, the height of each flow channel 111 is greater than the width of the flow channel. In this case, the flow channel has an open top and the two-phase coolant fluid / vapor flowing through the channel 111 can escape at the outlet 113 (open top of the flow channel or along the tip region of the fins 103).

[0033] In an embodiment, the cold plate 100 includes an extended vapor channel 109 coupled between the outlet port 107 of the cold plate 100 and the housing 101. The extended vapor channel 109 can be implemented as an extension of the housing 101, which is narrower than the housing 101, where the extended vapor channel 109 can include an intermediate holding region to direct the vapor from the housing 101 to the outlet port 107. For example, during operation, the extended vapor channel 109 can be immersed in the single-phase coolant fluid of the immersion environment. As the vapor that is evaporated (under pressure caused by the volume change within the housing 101) is directed from the housing 101 to the outlet port 107 via the extended vapor channel 109, the extended vapor channel 109 can further condense some of the vapor into a liquid phase, as Figure 2 shown, the condensed liquid can directly flow back to the interior region of the housing 101 or the cold plate 100 due to gravity. Thus, the extended vapor channel 109 can increase the accelerated cooling of the overall cold plate 100.

[0034] Figure 2 A block diagram of an immersion server system 200 utilizing local accelerated cooling is shown, according to an embodiment. The server system 200 can include a server enclosure 201 having one or more servers 202 housed therein. The servers 202 can include high-density chips 203. As shown, by way of example, the cold plate 100 is directly coupled to the chips 203.

[0035] The servers 202 can be configured to provide IT services. In particular, the servers 202 can include host servers (referred to as host nodes) and / or one or more compute servers (also referred to as compute nodes, e.g., CPU servers and GPU servers). The host servers (having one or more CPUs) typically interact with clients (not shown) over a network (e.g., the Internet) to receive requests for particular services, such as storage services (e.g., cloud-based storage services such as backup and / or restore), execute applications to perform certain operations (e.g., image processing, deep data learning algorithms or modeling, etc. as part of a software-as-a-service or SaaS platform). In response to the request, the host servers distribute tasks to one or more performance compute nodes or compute servers (having one or more GPUs) managed by the host servers. In an embodiment, the servers 202 can perform any type of computing task and / or can be any type of computing device (e.g., servers, storage devices, etc.). In an embodiment, the servers 202 can be edge computing devices. Thus, as the servers 202 provide the IT services, the heat generated by each server 202 is transferred to the single-phase or two-phase coolant.

[0036] The server system 200 can include an inlet port 205 and an outlet port 207. The inlet port 205 can be used to couple a system supply device to a supply line 215. The supply line 215 can be flexibly extended to the inlet port 105 of the cold plate 100 to supply the cold plate 100 with two-phase coolant fluid. The outlet port 207 can be used to couple a system return device to a return line 217. The return line 217 can be flexibly extended to the outlet port 107 of the cold plate to return vapor from the cold plate 100. In operation, the cold plate 100 can circulate two-phase coolant fluid to the high-density chip 203, while the rest of the server 202 can be immersed in a single-phase immersion coolant fluid. The extended vapor channel 109 of the cold plate 100 can be immersed in the single-phase immersion fluid and direct the vapor phase of the two-phase coolant fluid from the housing 101 to the outlet port 107. In addition, the extended vapor channel 109 can cool a portion of the vapor to a liquid phase of the two-phase fluid, which can be returned directly to the housing 101 under the force of gravity. The supply / return lines (or loop lines 215-217) can work in a passive manner under the force of gravity. For example, the cooled two-phase cooling fluid will enter the cold plate 100 via the line 215 and descend to the bottom of the housing 101 of the cold plate 100. As the two-phase cooling fluid absorbs heat and vaporizes into vapor, the vapor will rise to the extended vapor channel 109 of the housing 101 and then the vapor is discharged from the port 107 into the line 217.

[0037] Figure 3 A block diagram of an immersion system 300 for local accelerated cooling with single-phase fluid and two-phase fluid is shown, according to an embodiment. The immersion system 300 can be a server housing package that provides a single-phase coolant fluid immersion environment. The immersion system 300 can include an immersion container or tank 301. As shown, the immersion tank 301 can include a supply unit (supply manifold) 315 and a return unit (return manifold) 317. The supply unit 315 can be a supply manifold with one or more fluid connectors 305A-B. The return unit 317 can be a supply manifold with one or more vapor connectors 307A-B. These connectors 305A-B, 307A-B can be used to directly mate with server inlet ports 205A-B and outlet ports 207A-B by extending fluid line extension devices 215A-B and 217A-B, respectively. Figure 3

[0038] ​In one embodiment, the immersion tank 301 includes a condensation unit 309. The condensation unit 309 may include a collector 311, which is encapsulated together with the condensation unit 309. The condensation unit 309 may be coupled to a return unit 317. Vapor flowing to the condensation unit 309 may be condensed into a liquid phase, wherein the liquid two-phase coolant may be collected in the collector 311. The liquid two-phase coolant may then be supplied to a supply unit 315 via line 319. The condensation unit 309 may be connected to an external cooling source (not shown).

[0039] like Figure 3 As shown, the immersion tank 301 can be filled with coolant fluid (single-phase coolant fluid) 303. It can be seen that the server housing 201 is immersed in the single-phase coolant 303. In one embodiment, the server housing 201 may include a server 202 with chips directly bonded to two cooling plates 100A-B to provide two-phase thermal cooling to the chips. The cooling plates 100A-B are coupled at their inlet and outlet ports (not shown) to a supply unit 315 and a return unit 317 via connectors 205-207, 305-307 and extension lines 215-217 to circulate the two-phase coolant fluid 313, thereby cooling the high-density electronics of the server 202.

[0040] Figure 4 A front view of an immersion system 400 with one or more servers utilizing local accelerated cooling, according to one embodiment, is shown. Figure 4 As shown, one or more servers 202A-C are located within server housings 201A-C. Server housings 201A-C are housed in an immersion tank 301, and single-phase coolant 303 is supplied via pump 401 through an external supply device 403 and a return loop device 405. Figure 4 As shown, single-phase loops 403 / 405 are system-level loops, while two-phase loops consist of the following units: supply unit 315, liquid loop 215, cooling plate 100 in the server, vapor loop 217, reflux unit 317, condensation unit 309, and collector 311.

[0041] Figure 5 A side view of an immersion system with one or more servers utilizing local accelerated cooling, according to one embodiment, is shown. Immersion system 500 may represent immersion system 300. Figure 5 As shown, system 500 illustrates an entire system having both a single-phase coolant 303 and a two-phase coolant 313 for cooling electronic devices, contained in an immersion tank (e.g., an immersion housing) 301. Figure 5As shown, the server 202 is immersed in a single phase coolant 303, and the cold plate 100 is directly attached to the high density chip 203, where a loop circulates two phase coolant 313 from a condensing unit 309 (as shown) to the cold plate 100 to accelerate cooling of the high density chip 203. Figure 4 As shown, the server 202 is immersed in a single phase coolant 303, and the cold plate 100 is directly attached to the high density chip 203, where a loop circulates two phase coolant 313 from a condensing unit 309 (as shown) to the cold plate 100 to accelerate cooling of the high density chip 203.

[0042] The single phase coolant fluid 303 cools all equipment in contact with it, including all electronic devices immersed directly and indirectly in the single phase coolant fluid 303. The cold plate 100 is used to extract heat from the chip 203 through phase change of the two phase coolant 313 contained in the cold plate 100. By absorbing heat from the high density chip 203, the two phase coolant 313 generates a vapor phase in the cold plate 100, where the vapor flows to the expansion vapor channel 109, then to the reflux unit 317, and then to the condensing unit 309.

[0043] As can be seen, within the expansion vapor channel 109, due to partial or full immersion of the channel 109 in the single phase coolant 303, the channel 109 can condense some of the vapor into a liquid phase as shown by the (gravity driven) liquid flow 501. The liquid following the liquid flow 501 then directly refluxes to the two phase liquid region in the cold plate 100. A different portion of the vapor flows via flow 503 to the reflux unit 317, and then to the condensing unit 309 (not shown). The vapor at the condensing unit 309 is then condensed into a liquid phase, which portion of fluid will reflux to the cold plate 100 through the supply unit 315 as shown by the (gravity driven) liquid flow 505.

[0044] Due to the introduction of the cold plate 100 throughout the cooling system, the single phase coolant and the two phase coolant work together to extract heat from the chip 203. The fluid circulation path for the single phase coolant fluid 303 is separate from the fluid circulation path for the two phase coolant fluid 313, but by using the cold plate 100, the two fluids 303, 313 can work together to extract heat from the chip 203.

[0045] In the foregoing specification, embodiments of the disclosure have been described with reference to specific exemplary embodiments thereof. It is evident, however, that various modifications can be made thereto without departing from the broader spirit and scope of the disclosure as set forth in the following claims. The specification and drawings are, accordingly, to be regarded in an illustrative sense rather than a restrictive sense.

Claims

1. A cooling plate comprising: a fluid inlet port; a cooling enclosure thermally coupled to server electronics for accelerated cooling; an inlet channel coupled between the fluid inlet port and the cooling enclosure to direct two-phase fluid entering from the fluid inlet port into the cooling enclosure, wherein the cooling enclosure comprises: a plurality of heat spreading structures coupled to an inner surface of the cooling enclosure to form a plurality of spaces between the plurality of heat spreading structures, wherein the plurality of spaces increases a surface contact area between the two-phase fluid and the plurality of heat spreading structures that can be contained in the cooling enclosure to distribute heat from the plurality of heat spreading structures to the two-phase fluid to cause at least a portion of the two-phase fluid to become vapor-phase two-phase fluid; an extended vapor channel coupled to the cooling enclosure for collecting the vapor-phase two-phase fluid; and a vapor outlet port coupled to the extended vapor channel for expelling the vapor-phase two-phase fluid out of the cooling plate, wherein the extended vapor channel comprises an intermediate holding area for directing the vapor-phase two-phase fluid before being delivered to the vapor outlet port, and wherein the extended vapor channel is immersed in a single-phase fluid to exchange heat between the single-phase fluid and the vapor-phase two-phase fluid contained in the extended vapor channel to condense at least a portion of the vapor-phase two-phase fluid into liquid-phase two-phase fluid, wherein the liquid-phase two-phase fluid directly flows back to an interior region of the cooling enclosure.

2. The cooling plate of claim 1, wherein, The spaces between the heat spreading structures form fluid channels along a longitudinal direction of the heat spreading structures.

3. The cooling plate of claim 1, wherein, The cooling enclosure comprises an interior region containing the two-phase fluid, wherein the cooling enclosure separates the single-phase fluid surrounding the cooling enclosure from the two-phase fluid contained in the cooling enclosure when the cooling plate is immersed in the single-phase fluid.

4. The cooling plate of claim 1, wherein, The fluid inlet port is connected to a two-phase liquid supply and the vapor outlet port is connected to a vapor return of an immersion tank when the cooling plate is immersed in the immersion tank.

5. The cooling plate of claim 1, wherein, The cooling plate is immersed in an immersion tank containing a single-phase fluid, wherein a fluid flow of the single-phase fluid is separated from a fluid flow of the two-phase fluid within an interior region of the cooling enclosure.

6. The cooling plate of claim 1, wherein, The plurality of heat spreading structures are assembled or directly molded on the cooling enclosure.

7. The cooling plate of claim 1, wherein, A surface of the cooling enclosure interfaces with a chip to provide two-phase thermal cooling to the chip.

8. The cooling plate of claim 1, wherein, The vapor outlet port is coupled to the extended vapor channel via a first flexible hose and the fluid inlet port is coupled to the inlet channel via a second flexible hose.

9. An immersion tank for electronic devices comprising: an immersion enclosure; a distribution manifold coupled to the immersion enclosure, the distribution manifold comprising: at least one fluid supply connector, and at least one vapor return connector; and at least one cooling plate positioned below the at least one fluid supply device connector and the at least one vapor return device connector, wherein each of the at least one cooling plate comprises: a fluid inlet port coupled to a fluid supply device connector for receiving a two-phase fluid; a cooling enclosure thermally coupled to server electronics for accelerated cooling; an inlet channel coupled between the fluid inlet port and the cooling enclosure for directing the two-phase fluid entering from the fluid inlet port into the cooling enclosure, wherein the cooling enclosure comprises: a plurality of heat sink structures coupled to an inner surface of the cooling enclosure to form a plurality of spaces between the plurality of heat sink structures, wherein the plurality of spaces increases a surface contact area between the two-phase fluid and the plurality of heat sink structures that can be accommodated in the cooling enclosure to distribute heat from the plurality of heat sink structures to the two-phase fluid to cause at least a portion of the two-phase fluid to become a vapor-phase two-phase fluid; an expanded vapor channel coupled to the cooling enclosure for collecting the vapor-phase two-phase fluid; and a vapor outlet port coupled between the expanded vapor channel and a vapor return device connector for returning the vapor-phase two-phase fluid from the expanded vapor channel to the vapor return device connector, wherein the cooling plate is immersed in the immersion tank containing a single-phase fluid, wherein the expanded vapor channel comprises an intermediate holding area for directing the vapor-phase two-phase fluid before being delivered to the vapor outlet port, and wherein the expanded vapor channel is immersed in the single-phase fluid to exchange heat between the single-phase fluid and the vapor-phase two-phase fluid contained in the expanded vapor channel to condense at least a portion of the vapor-phase two-phase fluid into a liquid-phase two-phase fluid, wherein the liquid-phase two-phase fluid is directly returned to an interior region of the cooling enclosure.

10. The soak tank of claim 9, wherein, The spaces between the heat sink structures form fluid channels along a longitudinal direction of the heat sink structures.

11. The soak tank of claim 9, wherein, The cooling enclosure comprises an interior region containing the two-phase fluid, wherein the cooling enclosure separates the single-phase fluid surrounding the cooling enclosure from the two-phase fluid contained in the cooling enclosure.

12. The soak tank of claim 9, wherein, The fluid inlet port is connected to one of the at least one fluid supply device connector, and the vapor outlet port is connected to one of the at least one vapor return device connector of the immersion tank.

13. A server system comprising: a server enclosure having server electronics contained therein; at least one server inlet port; at least one server outlet port; at least one inlet expandable line coupled to the at least one server inlet port; at least one outlet extensible line coupled to the at least one server outlet port; and a cooling plate comprising: a fluid inlet port coupled to the at least one inlet extensible line for receiving a two-phase fluid from the at least one server inlet port; a cooling enclosure thermally coupled to a portion of the server electronic device for accelerated cooling; an inlet channel coupled between the fluid inlet port and the cooling enclosure for directing the two-phase fluid entering from the fluid inlet port into the cooling enclosure, wherein the cooling enclosure comprises: a plurality of heat dissipating structures coupled to an inner surface of the cooling enclosure to form a plurality of spaces between the plurality of heat dissipating structures, wherein the plurality of spaces increase a surface contact area between the two-phase fluid and the plurality of heat dissipating structures that can be accommodated in the cooling enclosure to distribute heat from the plurality of heat dissipating structures to the two-phase fluid to cause at least a portion of the two-phase fluid to become a vapor-phase two-phase fluid; an extended vapor channel coupled to the cooling enclosure for collecting the vapor-phase two-phase fluid; and a vapor outlet port coupled between the extended vapor channel and the at least one outlet extensible line for returning the vapor-phase two-phase fluid from the extended vapor channel to the at least one server outlet port, wherein the cooling plate is immersible into an immersion tank containing a single-phase fluid, wherein the extended vapor channel comprises an intermediate holding area for directing the vapor-phase two-phase fluid before being delivered to the vapor outlet port, and wherein the extended vapor channel is immersed in the single-phase fluid to exchange heat between the single-phase fluid and the vapor-phase two-phase fluid contained in the extended vapor channel to condense at least a portion of the vapor-phase two-phase fluid into a liquid-phase two-phase fluid, wherein the liquid-phase two-phase fluid is directly returned to an inner region of the cooling enclosure.

14. The server system of claim 13, wherein, the cooling enclosure comprises an inner region containing the two-phase fluid, and the cooling enclosure separates the single-phase fluid surrounding the cooling enclosure from the two-phase fluid contained in the cooling enclosure. the cooling enclosure comprises an inner region containing the two-phase fluid, and the cooling enclosure separates the single-phase fluid surrounding the cooling enclosure from the two-phase fluid contained in the cooling enclosure.

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