Patent Description:
Heat dissipation is an important consideration for computer systems. Notably, many components of a computer system, such as a processor (for example a central processing unit (CPU), a graphical processing unit (GPU), and the like), generate heat and thus require cooling to avoid performance degradation and, in some cases, failure. Similar considerations arise for systems other than computer systems (e.g., power management systems). Different types of cooling systems are therefore implemented to promote heat dissipation from heat-generating components, with the objective being to efficiently collect and conduct thermal energy away from heat-generating components.

Heat sinks rely on a heat transfer medium (e.g., a gas or liquid) to carry away the heat generated by a heat generating component. For example, a water block, which is a water cooling heat sink, is thermally coupled to the component to be cooled (e.g., a processor) and water, or other heat transfer fluid, is made to flow through a conduit in the water block to absorb heat from the heat generating component. As water flows out of the water block, so does the thermal energy collected thereby. As another example, immersion cooling systems have been gaining popularity whereby the heat generating component is immersed in a dielectric coolant or other immersion heat transfer fluid.

Said solutions typically rely on pumping systems to provide a flow of the heat transfer fluid, such that thermal energy may be carried away from the heat generating component. However, such solutions involving liquid and/or fluid for transferring heat are sometimes susceptible to leaks, obstructions in their cooling loop that disable a flow of the heat transfer fluid, or any other failures which can decrease their efficiency and, as such, cause the temperature of the heat generating component to increase.

There is therefore a desire for redundant cooling solutions that may be activated, or "triggered", before overheating of the heat generating component, in order to prevent overheating and any other damages of the heat generating component.

<CIT> discloses a water block assembly including first and second water block units having respective first and second fluid conduits. The second water block unit is stacked on the first water block unit. The second fluid conduit operates either in parallel with the first fluid conduit or fluidly independent therefrom, such that cooled fluid is fed to the first and second fluid conduits. The first water block unit includes a first base portion and a first cover portion disposed on and affixed to the first base portion. The first cover portion defines a first fluid inlet and a first fluid outlet of the first fluid conduit. The second water block unit includes a second base portion and a second cover portion disposed on and affixed to the second base portion. The second cover portion defines a second fluid inlet and a second fluid outlet of the second fluid conduit.

Embodiments of the present technology have been developed based on developers' appreciation of shortcomings associated with the prior art. The object of the invention is solved by a cooling system according to claim <NUM>. Preferred embodiments are presented in the dependent claims.

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

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.

For a better understanding of the present technology, as well as other aspects and further features thereof, reference is made to the following description which is to be used in conjunction with the accompanying drawings, where:
the backup heat transfer fluid flowing in the at least one fluid path is extracted from the tank by the backup pump.

In some embodiments of the present technology, the backup cooling loop is an open cooling loop fluidly connected to the tank.

In some embodiments of the present technology, the main cooling arrangement comprises a tank filled with a dielectric heat transfer fluid for immersive cooling of the heat generating component, the heat generating component being disposed within the tank such that thermal energy generated therefrom is collected by the dielectric heat transfer fluid; and an immersive cooling pump adapted for causing the dielectric heat transfer fluid to flow within the tank.

In some embodiments of the present technology, the main and backup heat transfer fluid are a same dielectric heat transfer fluid, and the main cooling arrangement comprises a tank filled with the dielectric heat transfer fluid for immersive cooling of the heat generating component, the heat generating component being disposed within the tank such that thermal energy generated therefrom is collected by the dielectric heat transfer fluid; and an immersive cooling pump adapted for causing the dielectric heat transfer fluid to flow within the tank, the at least one fluid path of the backup cooling arrangement being immersed within the tank and being fluidly connected therewith, the backup cooling arrangement further comprising a pump adapted for causing the dielectric heat transfer fluid to flow within the at least one fluid path.

In some embodiments of the present technology, the thermal fuse comprises a phase change material.

In some embodiments of the present technology, the phase change material comprises paraffin wax.

In some embodiments of the present technology, the backup cooling arrangement further comprises a temperature sensor adapted for sensing a temperature of the backup heat transfer fluid in the at least one fluid path, the temperature sensor being communicably connected to a controller.

In some embodiments of the present technology, the temperature sensor is adapted for providing to the controller a signal indicative of a temperature flow of the backup heat transfer fluid in the at least one fluid path for controlling the backup pump.

In some embodiments of the present technology, the temperature threshold is a melting temperature of the phase change material.

In some embodiments of the present technology, the thermal fuse is dissolved in the backup heat transfer fluid in response to its temperature being higher than the temperature threshold.

It should also be noted that, unless otherwise explicitly specified herein, the 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 systems 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.

An aspect of the present technology introduces a cooling system and a method for cooling of a heat generating component, for example a processor, with autonomously activable redundancy. In one embodiment, the cooling system comprises a main cooling arrangement thermally coupled to the heat generating component for cooling thereof. As it will be described in greater details hereinafter, the main cooling arrangement may comprise a liquid cooling block (also called "water block", "cold plate", or "thermal transfer device"), may be an immersive cooling arrangement, or any other cooling arrangement for providing suitable for cooling the heat generating component. The cooling system also comprises a backup cooling arrangement that provide redundancy to the main cooling arrangement. In this embodiment, the backup cooling arrangement is thermally coupled to the main cooling arrangement and comprises a thermal fuse. The thermal fuse is disposed such that it disables the operation of the backup cooling arrangement when a temperature of the thermal fuse is below a temperature threshold, and enables it in response to its temperature being above the temperature threshold.

In other words, the backup cooling arrangement may collect thermal energy of the main cooling arrangement, thereby providing cooling to the heat generating component, in response to the thermal energy generated by the heat generating component exceeding an amount of thermal energy that may be properly collected by the main cooling arrangement. For example, when a failure of the main cooling arrangement arises, thermal energy of the heat generating component is not properly collected and carried away by the main cooling arrangement. The temperature of the cooling system thus increases from a low initial temperature, and a state of the thermal fuse changes from a solid state to a melted state in response to its temperature exceeds a temperature threshold (e.g. a melting temperature of the thermal fuse) , thereby enabling an operation of the backup cooling arrangement to provide cooling to the heat generating component. In this embodiment, once the thermal fuse has melted, the state of the thermal fuse stays in the melted state in response to the temperature of the thermal fuse being below the temperature threshold.

In one embodiment, the backup cooling arrangement comprises a liquid cooling block having an internal fluid path for conducting a backup heat transfer fluid adapted for collecting thermal energy of the main cooling arrangement. The thermal fuse is disposed within the internal fluid path, initially being in a solid state to disable a flow of the backup heat transfer fluid within the liquid cooling block given that the thermal fuse and the internal fluid are at an initial temperature below the temperature threshold upon being disposed within the internal fluid path. When a failure of the first cooling system arises, for example a clogging of a liquid cooling block of the main cooling arrangement, the thermal energy causes the thermal fuse to change from the solid state to a melted state, thereby enabling the flow of the backup heat transfer fluid in the backup cooling arrangement. Thermal energy is thus collected and carried away by the backup cooling arrangement when a failure of the first cooling system arises. As described hereafter, other types of main and backup cooling arrangements are contemplated in alternative embodiments.

<FIG> is a schematic diagram of a cooling arrangement <NUM> comprising a liquid cooling block <NUM> installed on a heat generating component <NUM> to be cooled. For example, the heat generating component <NUM> may be a processor of a computer system and may be mounted to a mother board thereof. The computer system may be, for example and without limitation, a server of a datacentre disposed in a rack thereof. <FIG> is not to scale; while perimeters of the liquid cooling block <NUM> and of the heat generating component <NUM> may be similar, their relative sizes are for illustration purposes only.

In this illustrative example, the cooling arrangement <NUM> comprises a cooling loop <NUM> comprising the liquid cooling block <NUM> thermally coupled to the heat generating component <NUM>. The liquid cooling block <NUM> is a heat sink that uses a heat transfer fluid (e.g. water or another liquid) for transferring thermal energy. In some instances, the liquid cooling block <NUM> may be a water block and the heat transfer fluid may comprise water. It is to be understood that the term "liquid cooling block" is intended to include such thermal transfer devices that use water, or any fluids other than water and/or multiphase flow (e.g., two-phase flow). For example, in some instance, the fluid may be an oil, an alcohol, or a dielectric heat transfer fluid (e.g., <NUM> Novec ®).

The liquid cooling block <NUM> is configured to receive the heat transfer fluid that is circulated through a fluid path formed by the cooling loop <NUM> and an internal conduit <NUM> in the liquid cooling block <NUM>. Circulation of the heat transfer fluid in the internal conduit <NUM> allows to absorb the thermal energy from the heat generating component <NUM>. The liquid cooling block <NUM> defines a fluid inlet <NUM> and a fluid outlet <NUM> for respectively feeding and discharging the heat transfer fluid from the internal fluid conduit <NUM>. As the heat transfer fluid flows out of the liquid cooling block <NUM>, so does the thermal energy absorbed thereby.

The liquid cooling block <NUM> has an external thermal transfer surface <NUM> configured to be in thermal contact with the heat-generating component <NUM>. It is to be understood that in this context, the external thermal transfer surface <NUM> is said to be "in thermal contact" with the heat-generating component <NUM> whether the liquid cooling block <NUM> is in direct contact with the heat-generating component <NUM> or when a thermal paste is applied between the external thermal transfer surface <NUM> and the heat-generating component <NUM>, in a manner that is known in the art, to ensure adequate heat transfer between the heat-generating component <NUM> and the external thermal transfer surface <NUM>.

The cooling loop <NUM> further comprises a cooling apparatus <NUM> (e.g. a heat exchanger) configured for receiving the heated heat transfer fluid from the liquid cooling block <NUM>. As such, the heated heat transfer fluid discharged from the liquid cooling block <NUM> is cooled in the cooling apparatus <NUM> before returning to the liquid cooling block <NUM>. The cooling apparatus <NUM> through which the heat transfer fluid is cooled between the fluid outlet <NUM> and the fluid inlet <NUM> may be of various constructions, being for example an air-to-liquid heat exchanger or a liquid-to-liquid heat exchanger, and will not be described herein.

The cooling loop <NUM> also comprises a pump <NUM> to pump the heat transfer fluid into and out of the internal conduit <NUM> of the liquid cooling block <NUM>.

<FIG> is a top plan schematic representation of the liquid cooling block <NUM> mounted on the heat generating component <NUM>. In this illustrative example, the liquid cooling block <NUM> may for example comprise two redundant liquid inlets <NUM> and <NUM> respectively connectable to redundant conduits <NUM> and <NUM> (only their ends are shown) for receiving the heat transfer fluid. The heat transfer fluid may thus flow through redundant liquid channels <NUM> and <NUM> that zigzag within the liquid cooling block <NUM> to maximize the heat absorption potential of the heat transfer fluid across a surface of the liquid cooling block <NUM>. The liquid channels <NUM> and <NUM> terminate at two redundant liquid outlets <NUM> and <NUM> that are respectively connectable to redundant conduits <NUM> and <NUM> (only their ends are shown) for hot heat transfer fluid output.

Other shapes of the liquid cooling block <NUM> and/or shapes of its conduits are contemplated in alternative embodiments. For example, the liquid cooling block <NUM> may comprise a single internal conduit defining a spiral shape.

Broadly speaking, an aspect of the present technology is to introduce a cooling system with autonomously activable redundancy. As such, the cooling system comprises at least a main and a backup cooling arrangements, the backup cooling arrangement being thermally coupled to the main cooling arrangement for redundancy and comprising a thermal fuse. The thermal fuse is disposed such that it disables the operation of the backup cooling arrangement when a temperature of the thermal fuse is below a temperature threshold. More specifically, the thermal fuse opposes the flow of a backup heat transfer fluid within the backup cooling arrangement when a temperature of the backup heat transfer fluid and/or the thermal fuse is lower than the melting temperature of the thermal fuse.

<FIG> is a schematic diagram of a cooling system <NUM> comprising a main cooling arrangement <NUM>A and a backup cooling arrangement <NUM>B, each of the main and backup cooling arrangements <NUM>A, <NUM>B being similar to the cooling arrangement <NUM> described on <FIG>. More specifically, the main cooling arrangement <NUM>A is formed of a main cooling loop <NUM>A comprising a main liquid cooling block <NUM>A, a main pump <NUM>A and a main cooling apparatus <NUM>A, a main heat transfer fluid flowing in the main cooling loop <NUM>A. As previously described with respect to the liquid cooling block <NUM>, the main liquid cooling block <NUM>A defines an external thermal transfer surface <NUM>A configured to be in contact with the heat-generating component <NUM>, such that, in use, thermal energy thereof may be collected by the main heat transfer fluid flowing in an internal fluid conduit <NUM>A extending between a fluid inlet <NUM>A and a fluid outlet <NUM>A of the main liquid cooling block <NUM>A.

Similarly, the backup cooling arrangement <NUM>B forms a fluid path comprising a backup cooling loop <NUM>B including a backup liquid cooling block <NUM>B, a backup pump <NUM>B and a backup cooling apparatus <NUM>B, a backup heat transfer fluid flowing in the backup cooling loop <NUM>B upon activation of the backup cooling arrangement <NUM>B. Activation of the backup cooling arrangement <NUM>B is described in greater details hereafter. As previously described with respect to the liquid cooling block <NUM>, the backup liquid cooling block <NUM>B defines an external thermal transfer surface <NUM>B configured to be in thermal contact with an upper surface of the main liquid cooling block <NUM>A, the upper surface being opposed to the external thermal transfer surface <NUM>A. Mounting the backup liquid cooling block <NUM>B on a surface of the heat-generating component <NUM> opposite from a mounting surface of the main liquid cooling block <NUM>A is also contemplated. In use, thermal energy generated by the heat-generating component <NUM> may be collected by the backup heat transfer fluid flowing in an internal fluid conduit <NUM>B extending between a fluid inlet <NUM>B and a fluid outlet <NUM>B of the backup liquid cooling block <NUM>B. The main and backup heat transfer fluids may be the same or different types of fluids (e.g. the main heat transfer fluid may be demineralized water and the backup heat transfer fluid may be a refrigerant).

As such, the main and backup liquid cooling blocks <NUM>A, <NUM>B define a liquid cooling block assembly <NUM>. More specifically, the liquid cooling block assembly <NUM> comprises the main liquid cooling block <NUM>A, also referred to as the "lower" liquid cooling block <NUM>A, and the backup liquid cooling block <NUM>B, also referred to as the "upper" liquid cooling block <NUM>B stacked on the lower liquid cooling block <NUM>A such that, in use, the lower liquid cooling block <NUM>A is disposed between the upper liquid cooling block <NUM>B and the heat generating component <NUM>. As will be described in greater detail below, the lower and upper liquid cooling block <NUM>A, <NUM>B can, in some cases, provide the liquid cooling block assembly <NUM> with redundancy such that if the lower liquid cooling block <NUM>A were to experience a decrease in performance (e.g., due to a blockage in the fluid path at a level of the main cooling loop <NUM>A or within the internal fluid conduit <NUM>A), the upper liquid cooling block <NUM>B would continue cooling the target component <NUM>.

In this embodiment, the backup cooling arrangement <NUM>B comprises a thermal fuse <NUM> initially disposed within at least a portion of the backup cooling loop <NUM>B. The thermal fuse is configured for changing from a solid state to a melted state in response to its temperature being above a given temperature threshold (i.e. a "melting temperature" of the thermal fuse <NUM>). As such, a flow of the backup heat transfer fluid in the backup cooling loop <NUM>B is initially blocked due to the presence of the thermal fuse <NUM> disposed in its solid state.

The thermal fuse <NUM> is made of a material having a melting temperature higher than a normal operating temperature of the main heat transfer fluid and lower than a maximum safe operating temperature of the heat generating component <NUM>. In normal operation of the cooling system <NUM>, the temperature of the backup heat transfer fluid is lower than the melting temperature of the thermal fuse <NUM>. The thermal fuse <NUM> opposes the flow of the backup heat transfer fluid within the cooling loop of the backup cooling arrangement <NUM>B under such condition.

In this embodiment, the backup cooling arrangement <NUM>B comprises a controller <NUM> and a temperature sensor <NUM> for sensing a temperature of the heat generating component <NUM>, the temperature sensor <NUM> being communicably connected to the controller <NUM>. The backup pump <NUM>B is communicably connected to the controller <NUM> such that the controller <NUM> may, in response to the temperature sensor <NUM> sensing that a temperature of the heat generating component <NUM> is above a heat generating component temperature threshold (e.g. set according to the melting temperature of the thermal fuse <NUM>), actuate the backup pump <NUM>B.

In response to the temperature of the thermal fuse being above the temperature threshold, the flow of the backup heat transfer fluid is enabled, thereby providing additional cooling to the heat generating component <NUM> by the backup cooling arrangement <NUM>B.

More specifically, in the event of a failure of the main cooling arrangement <NUM>A or abnormal operation thereof (e.g. clogging of the main cooling loop <NUM>A), the main heat transfer fluid may be unable to suitably collect thermal energy expelled by the heat generating component <NUM>. For example, if a flow rate of the main heat transfer fluid decreases, the main heat transfer fluid may not carry thermal energy in a suitable manner so as to ensure proper cooling of the heat generating component <NUM>. As such, a temperature of the main heat transfer fluid and/or of the main liquid cooling block <NUM>A may rise. Given that the backup liquid cooling block <NUM>B is thermally coupled to the main liquid cooling block <NUM>A, and/or to the heat generating component <NUM>, the temperature of the backup liquid cooling block <NUM>B may similarly rise until a temperature of the thermal fuse <NUM> reaches the given temperature threshold, resulting in the melting of the thermal fuse <NUM> and dispersion of its melted material in the backup heat transfer fluid. As such, the backup cooling arrangement <NUM>B provides redundant cooling and may be autonomously activated in response to a rise of the temperature of the main heat transfer fluid. In this embodiment, the thermal fuse <NUM> is dissolved in the backup heat transfer fluid in response to its temperature being higher than the temperature threshold, thus enabling a flow of the backup heat transfer fluid in the backup cooling loop <NUM>B.

It may be noted that, once melted, the thermal fuse <NUM> no longer exists and is dispersed and/or dissolved within the backup heat transfer fluid. If the temperature of the backup heat transfer fluid is reduced below the melting temperature of the thermal fuse <NUM>, pieces of the material of the thermal fuse <NUM> may be expected to solidify and be carried by the backup heat transfer fluid.

As illustrated, the thermal fuse <NUM> may be disposed proximally to the outlet <NUM>B of the backup liquid cooling block <NUM>B and/or within the internal fluid conduit <NUM>B thereof on <FIG>. Other locations for disposing the thermal fuse <NUM> are contemplated in alternative embodiments of the present technology such as the inlet <NUM>B of the backup liquid cooling block <NUM>B. As an example and without limitation, the thermal fuse <NUM> may be made a phase change material (PCM), for example paraffin wax, or any other suitable material such as wax, resin, paraffin, grease, silicone, synthetic glue and polymers.

In this embodiment, the backup cooling arrangement <NUM>B further comprises a flow rate sensor <NUM> sensing a flow of the backup heat transfer fluid in the backup cooling loop <NUM>B. The controller <NUM> may be communicably connected to the flow rate sensor <NUM> and may receive data therefrom. In this embodiment, the flow rate sensor <NUM> may provide a visual information and/or transmit a signal to the controller <NUM> in response to the flow rate of the backup heat transfer fluid is non-null. As such, an operator of the cooling system <NUM> may be provided with the visual information that the flow rate of the backup heat transfer fluid is non-null, the visual information being indicative that a temperature of the main cooling arrangement <NUM>A has increased and that the temperature of the thermal fuse <NUM> has reached the temperature threshold.

<FIG> depict alternative embodiments of the present technology with different types of main and backup cooling arrangements for immersive cooling of the heat generating component <NUM>. Similarly to the backup cooling arrangement <NUM>B described on <FIG>, backup cooling arrangements described in <FIG> hereafter are autonomously activable.

<FIG> is a schematic diagram of a cooling system <NUM> comprising the main cooling arrangement <NUM>A, a backup cooling arrangement <NUM>C and an immersion cooling arrangement <NUM>D.

In this embodiment, the immersion cooling arrangement <NUM>D comprises a tank <NUM> filled with a dielectric heat transfer fluid for collecting thermal energy of the heat generating component <NUM>, the heat generating component <NUM> being disposed within the tank <NUM>. As such, the main cooling arrangement <NUM>A, including the heat generating component <NUM> and the main liquid cooling block <NUM>A, is at least partially immersed in the dielectric heat transfer fluid. An immersive cooling pump <NUM>, or simply "pump <NUM>", fluidly connected to the tank <NUM> is configured for maintaining a flow of the dielectric heat transfer fluid within the tank. The pump <NUM> may be external with respect to the tank <NUM> or immersed within the tank <NUM>. A cooling apparatus (not shown) may be provided along the external fluid conduit <NUM> to cool the dielectric heat transfer fluid. On the illustrative example of <FIG>, the pump <NUM> causes a flow of the dielectric heat transfer fluid from a surface of the tank <NUM> to a bottom of the tank <NUM> such that tank <NUM> receives cooled dielectric heat transfer fluid at a tank inlet <NUM>.

In this embodiment, the backup cooling arrangement <NUM>C comprises an open cooling loop comprising a backup liquid cooling block <NUM>C defining an internal fluid conduit <NUM>C extending between a fluid inlet <NUM>C and a fluid outlet <NUM>C of the backup liquid cooling block <NUM>C. As depicted on <FIG>, the backup liquid cooling block <NUM>C defines an external thermal transfer surface configured to be in contact with an upper surface of the main liquid cooling block <NUM>A such that the backup liquid cooling block <NUM>C is thermally coupled to the main liquid cooling block <NUM>A. In this embodiment, the backup cooling arrangement <NUM>C comprises an immersed fluid conduit <NUM>C extending between the tank inlet <NUM> and the fluid inlet <NUM>C such that the backup liquid cooling block <NUM>C is fluidly connected to the tank inlet <NUM>. As such, the tank inlet <NUM> parallelly provides cooled dielectric heat transfer fluid to the backup liquid cooling block <NUM>C and to the tank <NUM>.

The thermal fuse <NUM> is initially disposed within the open cooling loop of the backup cooling arrangement <NUM>C. As an example, the thermal fuse <NUM> is disposed in its solid state at or near the fluid outlet <NUM>C of the backup liquid cooling block <NUM>C on <FIG>. Other locations for disposing the thermal fuse <NUM> are contemplated in alternative embodiments of the present technology such as the inlet <NUM>C of the backup liquid cooling block <NUM>C. As such, in response to the temperature of the main heat transfer fluid flowing within the main liquid cooling block <NUM>A being above the melting temperature of the thermal fuse <NUM>, the state of the thermal fuse <NUM> change from the solid state to the melted state, thereby enabling a flow of the dielectric heat transfer fluid within the internal fluid conduit <NUM>C, the flow being selectively maintained by the immersed backup pump <NUM>C that extracts and returns the dielectric heat transfer fluid to and from the tank <NUM>.

The backup cooling arrangement <NUM>C may also comprise a flow rate sensor <NUM>', similar to the flow rate sensor <NUM>, to sense a flow of the dielectric fluid within the open cooling loop (e.g. within the immersed fluid conduit <NUM>C). In a non-limiting embodiment, the flow rate sensor <NUM>' may be communicably connected to a controller (not shown) to provide data thereto, the data comprising indication of a flow of the dielectric fluid within the open cooling loop.

<FIG> is a schematic diagram of a cooling system <NUM> in which the cooling arrangement <NUM>D is a main cooling arrangement, the cooling system <NUM> also comprising the backup cooling arrangement <NUM>B. In this embodiment, the main cooling arrangement <NUM>D comprises the tank <NUM> filled with the dielectric heat transfer fluid, the pump <NUM> and the external fluid conduit <NUM>. The main cooling arrangement <NUM>D may also comprise a cooling apparatus (not shown) thermally connected to the external fluid conduit <NUM> to cool the dielectric heat transfer fluid. In other words, the thermal energy generated by the heat generating component <NUM> is primarily collected by the dielectric heat transfer fluid under normal operation conditions of the main cooling arrangement <NUM>D.

In this embodiment, the external thermal transfer surface <NUM>B of the backup liquid cooling block <NUM>B is disposed in contact, either directly or by use of a thermal paste, with the heat generating component <NUM>, such that the backup liquid cooling block <NUM>B is thermally connected thereto. As such, in the event of a rise of the temperature of the heat generating component <NUM> and/or of the temperature of the dielectric heat transfer fluid in a vicinity of the thermal fuse that may be, for example, due to a failure of the pump <NUM>, the temperature of the thermal fuse <NUM> rises. In response to the temperature of the thermal fuse <NUM> being above the melting temperature, the state of the thermal fuse <NUM> changes from the solid state to the melted state, thereby enabling a flow of the backup heat transfer fluid in the cooling loop of the backup cooling arrangement <NUM>B, the flow being maintained by the backup pump <NUM>B. Therefore, thermal energy generated by the heat generating component <NUM> that may not be properly collected by the dielectric heat transfer fluid of the main cooling arrangement <NUM>D is collected by the backup heat transfer fluid flowing in the internal conduit <NUM>B of the backup liquid cooling block <NUM>B. It is contemplated that the pump <NUM> may be mounted in the tank <NUM> and submerged in the dielectric heat transfer fluid.

As described with respect to <FIG>, the backup cooling arrangement <NUM>B of the cooling system <NUM> comprises the controller <NUM> and the temperature sensor <NUM> for sensing a temperature of the heat generating component <NUM>, the temperature sensor <NUM> being communicably connected to the controller <NUM>. The backup pump <NUM>B is communicably connected to the controller <NUM> such that the controller <NUM> may, in response to the temperature sensor <NUM> sensing a temperature of the heat generating component <NUM> above the heat generating component temperature threshold (e.g. set according to the melting temperature of the thermal fuse <NUM>), actuate the backup pump <NUM>B.

In this embodiment, a plurality of fins <NUM>B may be disposed on an upper surface of the backup liquid cooling block <NUM>B, the upper surface being opposed to the external thermal transfer surface <NUM>B, the plurality of fins <NUM>B facilitating dissipation of thermal energy collected by the backup heat transfer fluid into the dielectric heat transfer fluid flowing in the tank <NUM>. Additionally or optionally, a layer of a porous material (not shown) may be disposed on the upper surface of the backup liquid cooling block <NUM>B, the porous material being made of a material selected such that nucleate boiling of the porous material arises in response to the temperature of the backup heat transfer fluid being higher than a boiling temperature threshold. Thermal energy may thus be transferred from the backup heat transfer fluid to the dielectric heat transfer fluid via nucleate boiling of the porous material.

<FIG> is a schematic diagram of a cooling system <NUM> in which the cooling arrangement <NUM>D is a main cooling arrangement, the cooling system <NUM> also comprising a backup cooling arrangement <NUM>E. In this embodiment, the heat generating component <NUM> is at least partially immersed within the tank <NUM> with the dielectric heat transfer fluid. The backup cooling arrangement <NUM>E comprises a fluid conduit <NUM> defining a fluid inlet <NUM> and a fluid outlet <NUM>, the fluid conduit <NUM> being immersed within the tank <NUM>. The backup cooling arrangement <NUM>E further comprises a backup pump <NUM> immersed in the dielectric heat transfer fluid and configured for maintaining a flow of the dielectric heat transfer fluid within the fluid conduit <NUM>.

In this embodiment, the thermal fuse <NUM> is initially disposed in its solid state within the fluid conduit <NUM> such that the flow of the dielectric heat transfer fluid within the fluid conduit <NUM> is opposed by the thermal fuse <NUM>. In response to the temperature of the thermal fuse <NUM> being higher than its melting temperature (e.g. due to overheating of the heat generating component <NUM> and/or a failure of the main cooling arrangement <NUM>D), the thermal fuse <NUM> melts such that a flow of the dielectric heat transfer fluid is enabled in fluid conduit <NUM> and maintained by the backup pump <NUM>. The thermal fuse may be disposed at any point within the fluid conduit <NUM>.

Upon the thermal fuse <NUM> being melted, the fluid conduit <NUM>, in collaboration with the backup pump <NUM>, causes the dielectric heat transfer fluid of the tank <NUM> to be directed from the fluid outlet <NUM> to the fluid inlet <NUM>, the fluid inlet <NUM> being located in a vicinity of the heat generating component <NUM> such that a collection of thermal energy generated therefrom may be facilitated. Indeed, the fluid conduit <NUM> and the backup pump <NUM> may increase a fluid velocity of the dielectric heat transfer fluid around the heat generating component, thereby accelerating thermal energy carriage by the dielectric fluid in a vicinity of the heat generating component <NUM>.

In this embodiment, the backup cooling arrangement <NUM>E comprises a controller <NUM>" that may be similar to the controller <NUM>, and a temperature sensor <NUM>" for sensing a temperature of the heat generating component <NUM>, the temperature sensor <NUM>" being communicably connected to the controller <NUM>". The backup pump <NUM> is communicably connected to the controller <NUM>", the controller <NUM>" actuating the backup pump <NUM> in response to the temperature sensor <NUM>" sensing a temperature of the heat generating component <NUM> being above the heat generating component temperature threshold (e.g. set according to the melting temperature of the thermal fuse <NUM>).

The backup cooling arrangement <NUM>E also comprise a flow rate sensor <NUM>", similar to the flow rate sensor <NUM>, to sense a flow of the dielectric fluid within the fluid conduit <NUM>. In a non-limiting embodiment, the flow rate sensor <NUM>" may be communicably connected to the controller <NUM>" to provide data thereto, the data comprising indication of a flow of the dielectric fluid within the open cooling loop.

The backup cooling arrangement <NUM>E may also comprise a flow rate sensor (not shown), similar to the flow rate sensor <NUM>, to sense a flow of the dielectric fluid within the fluid conduit <NUM>. In a non-limiting embodiment, the flow rate sensor may be communicably connected to the controller <NUM>" to provide data thereto, the data comprising indication of a flow of the dielectric fluid within the fluid conduit <NUM>.

It should be expressly understood that not all technical effects mentioned herein need to be enjoyed in each and every embodiment of the present technology.

Claim 1:
A cooling system (<NUM>, <NUM>, <NUM>, <NUM>) for cooling a heat generating component (<NUM>), the cooling system comprising:
a main cooling arrangement (1100A, 1100D) thermally coupled to the heat generating component (<NUM>), and configured for collecting thermal energy of the heat generating component (<NUM>) via a main heat transfer fluid; and
a backup cooling arrangement (1100B, 1100C, 1100E) thermally coupled to the main cooling arrangement (1100A, 1100D), the backup cooling arrangement (1100B, 1100C, 1100E) comprising:
at least one fluid path configured for conducting a backup heat transfer fluid;
the cooling system (<NUM>, <NUM>, <NUM>, <NUM>) being characterized in that the backup cooling arrangement (1100B, 1100C, 1100E) further comprises:
a thermal fuse (<NUM>) disposed within at least a portion of the at least one fluid path, the thermal fuse (<NUM>) changing from a solid state to a melted state and selectively enabling a flow of the backup heat transfer fluid in the at least one fluid path of the backup cooling arrangement (1100B, 1100C, 1100E) in response to its temperature being above a temperature threshold, the backup heat transfer fluid being configured to, upon flowing in the at least one fluid path, collect thermal energy from the main cooling arrangement (1100A, 1100D).