Patent Description:
Electronic equipment, for example servers, memory banks, computer disks, and the like, is conventionally grouped in equipment racks. Large data centers and other large computing facilities may contain thousands of racks supporting thousands or even tens of thousands of rack-mounted electronic assemblies containing servers and associated electronic equipment. The racks, including equipment mounted in their backplanes, consume large amounts of electric power and generate significant amounts of heat, that should be quelled or at least dissipated in order to avoid individual electronic component failures and ensure reliable and consistent operations.

Various cooling measures have been implemented to address the heat generated by the rack-mounted assemblies. One such measure provides a direct liquid cooling block configuration, that is deployed in addition to, or in replacement of, traditional forced-air cooling. In this configuration, cooling plates or blocks are configured with internal conduits to accommodate the circulation of cool channelized liquid (e.g., water). These liquid cooling blocks are directly mounted onto heat-generating electronic components, such as processors, to displace heat from the processors into the channelized liquid flowing through the liquid cooling blocks that, in turn, is forwarded towards heat exchangers.

Another cooling measure provides an immersion cooling configuration, in which the heat-generating electronic components of rack-mounted assemblies are submerged in a container that is at least partially filled with a non-conducting cooling fluid, such as, for example, an oilbased dielectric cooling fluid. In this manner efficient thermal contact and heat transfer is achieved between the heat-generating electronic components and the cooling dielectric cooling fluid.

Recently, hybrid liquid cooling systems have been proposed intended to exploit the benefits of both direct liquid cooling block and immersion cooling configurations in order to maximize the overall cooling efficiency of the rack-mounted assemblies. In particular, such liquid cooling systems deploy the liquid cooling blocks directly mounted onto heat-generating electronic components to circulate the cooling channelized liquid in combination with the submergence of the heat-generating electronic components into an immersion dielectric cooling fluid.

However, it has been observed that such liquid cooling systems may be susceptible to certain malfunctions, such as, for example, leakages of the channelized liquid from the coupling components of the liquid cooling block onto the electronic components, the immersion dielectric cooling fluid, and/or other rack-mounted assemblies.

These leakage issues may be particularly problematic, as the channelized cooling liquid may comprise water or other liquids that provide adequate heat transfer performance for channelized cooling but may not be suitable for immersion cooling due to its conductivity and/or corrosive properties of exposed electronic components. For example, if water is used as the channelized cooling liquid, it is likely that the concentration of ions in the water will cause the water to be sufficiently conductive to cause damage to electronic components. And, even if the water is initially distilled or deionized, the concentration of ions will increase as the water is circulated through the channelized cooling system.

As such, there is an interest in developing an arrangement for detecting and deflecting fluid leakages in liquid cooling systems.

It will be appreciated that the subject matter discussed in the background section should not be assumed to be prior art merely based as result of being mentioned in the background section. Similarly, drawbacks indicated in the background section or associated with the subject matter of the background section should not be assumed to have been previously recognized in the prior art. The subject matter in the background section merely represents different approaches.

<CIT> discloses an immersion cooling system including a plurality of spaced-apart cooling plated defining a plurality of subvolumes therebetween, a second liquid cooling flowing through at least a portion of each cooling plate, and at least one electronic device at least partially immersed in the first liquid coolant within each subvolume.

<CIT> discloses a metal hose connected between a radiator and a cold plate that cools a CPU, or similar electronic heat generating component, whereby the metal hose is connected to the radiator with silicon casings.

The embodiments and examples of the present disclosure are provided based on developers' understanding of the drawbacks associated with liquid cooling systems experiencing leakage issues of the liquid cooling blocks within a rack-mounted assembly or onto other rack-mounted assemblies.

The object of the invention is solved by a leakage deflection arrangement according to claim <NUM>, a rack system according to claim <NUM> and a method according to claim <NUM>. Preferred embodiments are presented in the dependent claims.

In the context of the present specification, unless expressly provided otherwise, a computer system may refer, but is not limited to, an "electronic device", an "operation system", a "system", a "computer-based system", a "controller unit", a "monitoring device", a "control device" and/or any combination thereof appropriate to the relevant task at hand.

In the context of the present specification, unless expressly provided otherwise, the expression "computer-readable medium" and "memory" are intended to include media of any nature and kind whatsoever, non-limiting examples of which include RAM, ROM, disks (CD-ROMs, DVDs, floppy disks, hard disk drives, etc.), USB keys, flash memory cards, solid state-drives, and tape drives. Still in the context of the present specification, "a" computer-readable medium and "the" computer-readable medium should not be construed as being the same computer-readable medium. To the contrary, and whenever appropriate, "a" computer-readable medium and "the" computer-readable medium may also be construed as a first computer-readable medium and a second computer-readable medium.

In the context of the present specification, unless expressly provided otherwise, the words "first", "second", "third", etc. have been used as adjectives only for the purpose of allowing for distinction between the nouns that they modify from one another, and not for the purpose of describing any particular relationship between those nouns.

Implementations of the present technology each have at least one of the above-mentioned objects and/or aspects, but do not necessarily have all of them. It should be understood that some aspects of the present technology that have resulted from attempting to attain the above-mentioned object may not satisfy this object and/or may satisfy other objects not specifically recited herein.

It will be appreciated that, unless otherwise explicitly specified herein, the representative drawings are not to scale.

The examples and conditional language recited herein are principally intended to aid the reader in understanding the principles of the present technology and not to limit its scope to such specifically recited examples and conditions. It will be appreciated that those skilled in the art may devise various arrangements that, although not explicitly described or shown herein, nonetheless embody the principles of the present technology.

Moreover, all statements herein reciting principles, aspects, and implementations of the present technology, as well as specific examples thereof, are intended to encompass both structural and functional equivalents thereof, whether they are currently known or developed in the future. Thus, for example, it will be appreciated by those skilled in the art that any block diagrams herein represent conceptual views of illustrative systems embodying the principles of the present technology.

With these fundamental principles in place, we will now consider some non-limiting examples to illustrate various implementations of aspects of the present disclosure.

<FIG> illustrates a perspective view of a rack system <NUM> for housing numerous liquid cooled rack-mounted electronic assemblies <NUM> comprising an electronic device <NUM> (e.g., server) and associated electronic components <NUM>, in accordance with the nonlimiting examples of the present disclosure. As shown, the rack system <NUM> includes a rack frame <NUM>, racking shelves <NUM>, rack-mounted electronic assemblies <NUM>, a power distribution unit (PDU) <NUM>, a rack liquid cooling inlet conduit <NUM>, and a rack liquid cooling outlet conduit <NUM>.

The racking shelves <NUM> are configured to accommodate the rack-mounted electronic assemblies <NUM> onto the rack frame <NUM>, in which the electronic assemblies <NUM> may be oriented vertically with respect to the rack frame <NUM> in order to maximize the number of rack-mounted assemblies <NUM> housed within the rack frame <NUM>. In some examples, guide members (not shown) may be incorporated on racking shelves <NUM> to slidably guide the rack-mounted assemblies <NUM> into position during racking and de-racking operations.

The rack liquid cooling inlet conduit <NUM> is configured to receive a cooling liquid <NUM> from an external source (e.g., heat exchanger) that is channely routed to cooling blocks <NUM> (as shown in <FIG>) and are directly mounted onto electronic components <NUM> (as shown in <FIG>) of the rack-mounted electronic assemblies <NUM>. In turn, the channeled cooling liquid <NUM> of the cooling blocks <NUM> that is subjected to the heat generated by the electronic components <NUM> is subsequently routed to the external source for thermal cooling reconditioning.

The PDU <NUM> is configured to controllably supply electrical power to the rack-mounted electronic assemblies <NUM> electronic components <NUM> (as shown in <FIG>). As described in greater detail below, the supply of electrical power by the PDU <NUM> is monitored and controlled based on a power controller <NUM> and associated sensors <NUM> that are communicatively coupled to the PDU <NUM>.

It should be appreciated that rack system <NUM> may include other operational components, such as, for example, heat exchangers, cables, connectors, tubing constructs, pumps, and the like. However, such components have been omitted from <FIG> for clarity and tractability purposes of the general inventive concepts provided by the disclosed examples.

<FIG> depicts a schematic diagram of a fluid leakage detection and deflection arrangement <NUM> for a liquid cooled rack-mounted electronic assembly <NUM>, in accordance with the nonlimiting examples of the present disclosure. As shown, the liquid cooled rack-mounted electronic assembly <NUM> incorporates an electronic device <NUM> that includes one or more electronic processing components <NUM> (only one of which is illustrated in <FIG> for clarity) mounted on an electronic board <NUM>. In nonlimiting examples, the electronic device <NUM> may embody a computer server, such as, for example, a Dell™ PowerEdge™ Server running a Microsoft™ Windows Server™ operating system. It will be appreciated, however, that electronic device <NUM> may be implemented in any other suitable hardware, software, and/or firmware, or a combination thereof.

In the nonlimiting examples provided by the fluid leakage detection and deflection arrangement <NUM>, the liquid cooled rack-mounted electronic assembly <NUM> incorporates a liquid immersion cooling configuration in combination with a direct liquid cooling block configuration. The liquid immersion cooling configuration deploys an immersion cooling case <NUM> containing a volume of a first cooling liquid <NUM>, such as, for example, a dielectric cooling fluid. The electronic board <NUM> comprising the electronic device <NUM> and associated electronic processing components <NUM> are at least partially submerged in the immersion cooling fluid <NUM> for ambient cooling purposes thereof.

The electronic processing components <NUM> of the electronic device <NUM> are additionally cooled by a direct liquid cooling block configuration that channels a second cooling liquid <NUM> therethrough. The direct liquid cooling block configuration deploys one or more liquid cooling blocks <NUM> (only one of which is illustrated in <FIG> for clarity) that are directly mounted onto the electronic processing components <NUM> of the electronic device(s) <NUM> for optimal thermal transfer. The channelized second cooling liquid <NUM> may comprise any combination of water, alcohol, glycol, or any other suitable liquid capable of sustaining adequate cooling temperatures.

As noted above, the liquid cooling block <NUM> incorporates an internal conduit to accommodate the circulation of the channelized second cooling liquid <NUM> therethrough that serves to absorb and extract the heat generated by the electronic processing components <NUM>. The internal conduit of liquid cooling block <NUM> may be configured to embody various formations, such as, for example, snake-like, zigzag, and/or looped configurations, etc. to maximize the surface area for heat absorption potential of the channelized second cooling liquid <NUM> flowing through the cooling block <NUM>.

It should be appreciated that the direct mounting of the liquid cooling blocks <NUM> onto the electronic processing components <NUM> is meant to encompass configurations in which thermal pastes or thermally conductive film materials are applied between a surface of the electronic component <NUM> and an interfacing surface of the liquid cooling block <NUM>.

Returning to the arrangement <NUM> of <FIG>, the channelized second cooling liquid <NUM> may be supplied by an external source, such as, for example, from a heat exchanger or dry cooler (not shown) to the liquid cooling inlet conduit <NUM> of rack system <NUM> (see, <FIG>) that, in turn, forwards the cooling liquid <NUM> via a channelized liquid loop <NUM>, to an input side of a serpentine convection coil <NUM>. The serpentine convection coil <NUM> may be structured with multiple hollow-channel coils to provide a high surface area exposure relative to the the dielectric cooling fluid <NUM> while also maintaining compact overall length and width dimensions. With this structure, the serpentine convection coil <NUM> operates to internally convey the circulating channelized second cooling liquid <NUM> that operates to both, cool the ambient the immersion dielectric cooling fluid <NUM> as well as forward the channelized cooling liquid <NUM> to the liquid cooling block <NUM> in direct thermal contact with the electronic processing components <NUM>.

As shown, the liquid cooling block <NUM> is configured with a liquid inlet <NUM>, fluidly connected to an output side of the serpentine convection coil <NUM>, for receiving the channelized second cooling liquid <NUM> from the serpentine convection coil <NUM>. The received channelized second cooling liquid <NUM> is then circulated through by the internal conduit of the liquid cooling block <NUM>. The liquid cooling block <NUM> further incorporates a liquid outlet <NUM> for discharging the second cooling liquid <NUM> warmed by the electronic components <NUM> to a heat exchanger or dry cooler (not shown), via the channelized liquid loop <NUM>, for thermal cooling reconditioning.

The arrangement <NUM> may also implement a fluid deflection unit <NUM> fixedly attached to the liquid cooling block <NUM>. As explained in greater detail below, the fluid deflection unit <NUM> operates to shield the electronic processing components <NUM> from fluid leakages stemming from the liquid cooling block <NUM> by diverting such leakages away from the electronic processing components <NUM>. In other words, the fluid deflection unit <NUM> prevents the electronic components <NUM> from being in contact with a leaking liquid distinct from the cooling fluid <NUM> by diverting leaking liquid away from the electronic processing components <NUM>.

The arrangement <NUM> may further comprise an electric power controller <NUM>, a switching device <NUM>, and one or more measurement sensors <NUM> communicatively coupled to the controller <NUM>. The electric power controller <NUM> may be mounted onto the electronic board <NUM> of electronic device <NUM> and may be operatively coupled to the PDU <NUM> via the switching device <NUM>. In various examples, the switching device <NUM> may be integrated within the electronic device <NUM> or may be located outside the electronic device <NUM> (e.g. along a power line that supplies electric power from the PDU <NUM> to the electronic device <NUM>). The power controller <NUM> is configured to receive signals from the communicatively coupled measurement sensors <NUM> and execute messages and/or command instructions in response to the received measurement signals.

In various nonlimiting examples, the measurement sensors <NUM> are disposed at a lower portion of the electronic board <NUM> and are configured to detect certain properties of the fluid settling at the lower portion of the board <NUM>. That is, the channelized cooling liquid <NUM> of the cooling blocks <NUM> typically has a higher density than the density of the immersion first cooling fluid <NUM>. As a result, in case of leakages by the cooling blocks <NUM>, the channelized second cooling liquid <NUM> will sink to a lower portion of the immersion case <NUM>. In some examples of the present technology, the measurement sensors <NUM> are mounted on the fluid deflection unit <NUM>. In those examples, the measurement sensors <NUM> are thus disposed near potential leakages that could occur at cooling blocks <NUM>.

Correspondingly, the measurement sensors <NUM> are disposed along a lower portion of the immersion case <NUM> to detect the presence of leaked channelized second cooling liquid <NUM> based on the measurement of certain properties of the fluid settling at the lower portion of the immersion case <NUM>. As such, the measurement sensors <NUM> may be configured to measure one or more physical/chemical properties and the levels of such properties of the fluid along the lower portion the immersion case <NUM> in order to detect the presence of the channelized second cooling liquid <NUM>. The detection of the physical/chemical properties and associated levels of the lower portion fluid of immersion case <NUM> may include, for example, measuring temperature, conductivity, viscosity, density, etc..

Upon the measurement sensors <NUM> detecting that the physical/chemical properties and/or associated levels indicate the presence of the channelized second cooling liquid <NUM> within the immersion case <NUM>, the sensors <NUM> communicate measurement signals reporting the same to the electric power controller <NUM>. In turn, the controller <NUM> operates to compare the reported measurement signals providing the physical/chemical property levels against predetermined acceptable threshold levels.

In certain nonlimiting examples, the electric power controller <NUM> is configured to provide command instructions and messaging signals comprising, inter alia: (a) normal operations message in response to sensors <NUM> reporting that the property levels are within acceptable threshold levels; (b) maintenance check message in response to sensors <NUM> reporting that the property levels are close to exceeding the threshold levels; and (c) a shutdown alert message along with command instructions to open the switching device <NUM> to disconnect power supplied by the PDU <NUM> to the corresponding rack-mounted assembly <NUM> or to an entire shelf <NUM> of rack-mounted assemblies <NUM>. In some examples, the switching device is part of the electronic device <NUM>. In these examples, the electric power controller <NUM> may communicate with the electronic device <NUM> and cause the switching device <NUM> to electrically disconnect the electronic device <NUM> from the PDU <NUM>.

As noted above, the fluid leakage monitoring and deflection arrangement <NUM> may incorporate a fluid deflection unit <NUM> mounted onto individual liquid cooling blocks <NUM> to shield associated electronic processing components <NUM> from leakages of the channelized second cooling liquid <NUM> stemming from the liquid cooling block <NUM>. To this end, <FIG> depicts a configuration <NUM> deploying liquid cooling block fluid deflection units 256A, 256B configured to shield related electronic processing components 122A, 112B from fluid leakages, in accordance with the examples of the present disclosure.

As shown, the liquid cooling block fluid deflection units 256A, 256B are fixedly attached onto respective liquid cooling blocks 250A, 250B which, in turn, are directly mounted on electronic processing components 122A, 122B of electronic device <NUM> (e.g., server). As noted above, the liquid cooling blocks 250A, 250B receive the channelized second cooling liquid <NUM> via a channelized liquid loop <NUM> and internally channel the second cooling liquid <NUM> therethrough to dissipate the heat generated by related electronic processing components 122A. Depending on various configurations supported by the disclosed examples, the channelized second cooling liquid <NUM> may be forwarded to a subsequent liquid cooling block 250B via the channelized liquid loop <NUM> (as shown) or may be directed back to a cooling liquid source (e.g., heat exchanger) for cooling reconditioning processing.

The attachment of the fluid deflection units 256A, 256B to the respective liquid cooling blocks 250A, 250B may be achieved by any suitable means, such as, for example, welding of the fluid deflection units 256A, 256B to the respective liquid cooling blocks 250A, 250B, fastening one or more fasteners (e.g. screws) through opening defined in the fluid deflection units 256A, 256B to the liquid cooling blocks 250A, 250B or to a plate welded thereon, or any other suitable manner.

The fluid deflection units 256A, 256B operate to shield the electronic processing components 122A, 122B from second cooling liquid <NUM> leakages stemming from the liquid cooling blocks 250A, 250B by incorporating an overhanging structure that diverts such leakages away from the electronic processing components 122A, 122B. To this end, <FIG> depict cross-sectional and surface perspective views of the structure of the fluid deflection units 256A, 256B, in accordance with the examples of the present disclosure.

As shown, <FIG> depicts nonlimiting examples of cross-sectional profiles of the structure of fluid deflection units 256A, 256B. In one example, the fluid deflection units 256A, 256B may embody an overhanging structure incorporating an angular linear cross-sectional profile 402A configured to downwardly divert fluid leakages away from electronic processing components 122A, 122B. In an alternative example, the fluid deflection units 256A, 256B may embody an overhanging structure incorporating a curved cross-sectional profile 402A configured to downwardly divert fluid leakages away from electronic processing components 122A, 122B.

<FIG> depicts nonlimiting examples of perspective top surface views of the structure of the fluid deflection units 256A, 256B. As shown, the top surfaces of the fluid deflection units 256A, 256B may further incorporate grooved channels 402B, 404B along the angular linear profile 402A and the curved cross-sectional profile 404A, respectively. The grooved channels 402B, 404B are configured to expedite the guidance of diverting fluid leakages away from electronic processing components 122A, 122B.

In this manner, the fluid leakage detection and deflection arrangement <NUM> is capable of detecting fluid leakages within an electronic processing assembly <NUM> as well as divert such leakages stemming from the liquid cooling block <NUM> away from electronic components <NUM> within the electronic processing assembly <NUM>.

However, as indicated above by <FIG>, rack system <NUM> comprises a plurality of vertically-disposed rows of horizontal racking shelves <NUM>, in which each row of the horizontal racking shelves <NUM> accommodates the placement of multiple rack-mounted electronic assemblies <NUM>. As such, it will be appreciated that any fluid leakages from rack-mounted electronic assemblies <NUM> disposed on uppers row of rack system <NUM> may spill over onto electronic assemblies <NUM> disposed on lower rows of rack system <NUM>.

To this end, <FIG> depicts a block diagram of a fluid deflection arrangement <NUM> for shielding an entire rack-mounted electronic processing assembly <NUM> from fluid leakages stemming from upper rack-mounted electronic assemblies <NUM> of rack system <NUM>, in accordance with the examples of the present disclosure. For clarity, <FIG> illustrates the rack-mounted electronic processing assembly <NUM> in an open withdrawn position to indicate the separation of the electronic device <NUM> (e.g., server) from the immersion case <NUM>.

As shown, the fluid deflection arrangement <NUM> incorporates a fluid deflection unit <NUM> comprising an overhanging structure fixedly attached to an upper portion of the electronic device <NUM>. The attachment of the fluid deflection unit <NUM> to the electronic device <NUM> may be achieved by any suitable means, such as, for example, by fastening fasteners (e.g. screws) through openings defined in the fluid deflection unit <NUM> and in the board <NUM>. As another example, the board <NUM> may define pins on an upper portion thereof (e.g. an upper edge thereof) such that said pins may be inserted in openings defined in the fluid deflection unit <NUM>. The pins may be adjusted (e.g. bended) to maintain connection between the fluid deflection unit <NUM> and the board <NUM>. Other attachment means are contemplated in alternative examples.

Similar to the nonlimiting configurations of fluid deflection units 256A, 256B noted above, the overhanging structure of fluid deflection unit <NUM> may embody an angular linear cross-sectional profile or a curved cross-sectional profile to downwardly divert fluid leakages away from the electronic device <NUM>. Moreover, the top surface of the overhanging structure of fluid deflection unit <NUM> may also embody grooved channels configured to expedite the guidance of diverting fluid leakages away from the electronic device <NUM>. The fluid deflection units 256A, 256B thus divert leaking fluid within the immersion case <NUM>, while the fluid deflection unit <NUM> diverts leaking fluid outside the immersion case <NUM>. The fluid deflection units 256A, 256B and the fluid deflection unit <NUM> may be combined in some examples of the present technology such that a given immersion case <NUM> is operably connected to a fluid deflection unit <NUM>, and the electronic device <NUM> enclosed in the immersion case <NUM> is prevent from being in contact with a leaking liquid distinct from the cooling liquid <NUM> by fluid deflection units 256A, 256B.

Equally notable, the fluid deflection arrangement <NUM> may also incorporate measurement sensors <NUM> disposed along a lower portion of the immersion case <NUM> to detect the presence of leaked channelized second cooling liquid <NUM> based on certain properties of the fluid settling at a lower portion of the immersion case <NUM>. As noted above, the measurement sensors <NUM> are communicatively coupled to power controller <NUM> (not shown) and are configured to determine one or more physical/chemical properties and report the levels of such properties to power controller <NUM>. Depending on the detected property levels reported by the measurement sensors <NUM>, the power controller <NUM> may provide command instructions and messaging signals comprising, inter alia: (a) normal operations message in response to sensors <NUM> reporting that the property levels are within acceptable threshold levels; (b) maintenance check message in response to sensors <NUM> reporting that the property levels are close to exceeding the threshold levels; and (c) a shutdown alert message along with instructions to open the switching device <NUM> to disconnect power supplied by the PDU <NUM> to the electronic device <NUM> of the corresponding rack-mounted assembly <NUM> or to an entire shelf <NUM> of rack-mounted assemblies <NUM>.

In this manner, the fluid deflection arrangement <NUM> is capable of detecting fluid leakages within an electronic processing assembly <NUM> as well as shielding an entire rack-mounted electronic processing assembly <NUM> from such leakages stemming from upper rack-mounted electronic assemblies <NUM> of rack system <NUM>.

With this said, it will be understood that, although the embodiments and examples presented herein have been described with reference to specific features and structures, various modifications and combinations may be made without departing from the disclosure. The specification and drawings are, accordingly, to be regarded simply as an illustration of the discussed implementations, embodiments or examples and their principles as defined by the appended claims, and are contemplated to cover any and all modifications, variations, combinations or equivalents that fall within the scope of the present disclosure, as long as they fall under the scope of the appended claims.

Claim 1:
A fluid leakage deflection arrangement (<NUM>, <NUM>) for a liquid-cooled rack-mounted electronic processing assembly (<NUM>), comprising:
an immersion case (<NUM>) containing a first cooling liquid (<NUM>) in which an electronic device (<NUM>) of the rack-mounted electronic processing assembly (<NUM>) is at least partially submerged therein, the electronic device (<NUM>) comprising electronic components (<NUM>);
the fluid leakage deflection arrangement (<NUM>, <NUM>) being characterised in that the fluid leakage deflection arrangement (<NUM>, <NUM>) further comprises:
a liquid cooling block (<NUM>) mounted on the electronic device (<NUM>) and in thermal contact with the electronic components (<NUM>) and incorporating an internal conduit to accommodate the circulation of a channelized cooling liquid (<NUM>) to absorb and extract thermal energy from the electronic components (<NUM>); and
a deflection unit (<NUM>, <NUM>) configured to prevent the electronic device (<NUM>) from being in contact with a leaking channelized cooling liquid by diverting leaking channelized cooling liquid away from the electronic components (<NUM>).