Passive cooling apparatus for cooling immersion fluid and power conversion apparatus, and related systems

Abstract

A passive fluid cooling system is provided, comprising: an immersion cooling tank containing a volume of fluid; and a plurality of fluid cooling channels attached to the outer sidewall of the immersion cooling tank. The fluid flows through a plurality of fluid cooling channels located on the outer side wall of the immersion cooling tank, thereby removing heat from the volume of fluid.

Description

[0001] Related Applications

[0002] This application claims the benefit and priority of Indian Provisional Application No. 202211033622 filed on June 13, 2022, entitled “Passive Cooling Device and Related System for Cooling Immersed Fluid and Power Conversion Equipment”, the contents of which are incorporated herein by reference as if set forth in their entirety herein. Technical Field

[0003] The present inventive concept relates generally to immersion fluids and, more particularly, to cooling of immersion fluids. Background Art

[0004] The most common method for cooling information technology (IT) equipment, such as equipment in data centers, power conversion equipment, etc., is forced air. Using air as a coolant typically requires fans, ductwork, heating ventilation and air conditioning (HVAC) systems, etc., which can take up a lot of space and consume more electricity, and often increase costs.

[0005] An alternative to using air to cool equipment is immersion cooling, which is more energy-efficient and space-efficient. Immersion cooling involves submerging system components in a fluid that, ideally, has a high heat absorption coefficient and low thermal resistance. In other words, the process typically requires the use of fluids that will not damage IT components or degrade system functionality. Additionally, for safety reasons, these fluids need to be "dielectric," meaning they do not conduct electricity. The dielectric fluids currently used for immersion cooling generally fall into two categories: oils (synthetic, mineral, bio-oils) and engineered fluids.

[0006] Immersion cooling methods involve immersing components and / or equipment in a dielectric fluid. Heat generated by IT components is absorbed by the fluid, which is then pumped and circulated inside a housing, base, or tank to help remove the heat. This requires pumping the hot oil / fluid out for cooling through a secondary air-to-liquid or liquid-to-liquid heat exchanger and pumping the cooled oil / fluid back into the immersion tank. Some methods include fully enclosed IT bases that contain dielectric fluids, so less fluid is generally required. Some methods include fully enclosed IT tanks / immersion tanks. These tanks contain dielectric fluids and are typically designed to accommodate IT components that would otherwise be mounted in a rack. Since immersion tanks can accommodate almost all types of IT components, there is no need to replace the immersion tank for IT upgrades. This makes the immersion tank method more attractive in terms of flexibility and cost relative to chassis cooling methods. While immersion cooling is feasible, there is still a need for improvement. Summary of the invention

[0007] Some embodiments of the present inventive concept provide a passive fluid cooling system, comprising: an immersion cooling tank containing a volume of fluid; and a plurality of fluid cooling channels attached to an outer side wall of the immersion cooling tank. The fluid flows through the plurality of fluid cooling channels located on the outer side wall of the immersion cooling tank, thereby removing heat from the volume of fluid.

[0008] In other embodiments, a plurality of fluid cooling channels may be attached to the immersion cooling tank at a first portion and a second portion of the immersion cooling tank. As the temperature of the fluid in the immersion cooling tank increases, the density of the fluid decreases, causing the less dense fluid to rise to the top of the immersion cooling tank and flow into the plurality of fluid cooling channels to cool the fluid, and then flow back into the immersion cooling tank at a bottom portion of the immersion cooling tank.

[0009] In yet other embodiments, the flow of the fluid through the plurality of fluid cooling channels reduces the temperature of the fluid, thereby providing a cooled fluid.

[0010] In some embodiments, the immersion cooling tank may further include electronic components located in the immersion cooling tank, and the cooled fluid may cool the electronic components located in the immersion cooling tank.

[0011] In other embodiments, fluid may be directed through the plurality of cooling channels without the use of fans and / or pumps, thereby improving power efficiency.

[0012] In yet other embodiments, the plurality of fluid cooling channels may have a shape selected from one of the following: a fin shape, a radial disk shape, a fractal design, a rectangular shape, a racetrack shape, a circular shape, a flat channel shape, and combinations thereof.

[0013] In some embodiments, the fluid may be thermally conductive and electrically insulating.

[0014] In other embodiments, the fluid may have electrical insulating properties to ensure that the fluid may safely contact energized electronic components.

[0015] In yet other embodiments, the fluid does not damage electronic components.

[0016] Passive cooling devices and immersion cooling tanks are also provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1A is a diagram illustrating an immersion tank including a plurality of fluid cooling channels according to some embodiments of the present inventive concept.

[0018] Figure 1B is a diagram illustrating one cooling channel (fin) among a plurality of cooling channels (fins) according to some embodiments of the present inventive concept.

[0019] Figure 2A is a cross-section illustrating an immersion tank including a plurality of components and a coolant and having fins according to some embodiments of the present inventive concept.

[0020] Figure 2B yes Figure 2A A perspective view of a system in which a tank according to some embodiments of the present inventive concept and a three-dimensional representation of multiple elements therein are shown.

[0021] FIG. 3A to FIG. 3C Graphs showing isochoric, isothermal and velocity vector diagrams, respectively, illustrating aspects of cooling using immersion fluids according to some embodiments of the present inventive concept.

[0022] Figure 4A is a diagram illustrating an immersion tank having hollow channel type fluid cooling channels according to some embodiments of the present inventive concept.

[0023] Figure 4B yes Figure 4A A cross section of an immersion tank with a hollow channel according to some embodiments of the present inventive concept is shown in FIG.

[0024] Figure 4C yes Figure 4B A perspective view of a section in FIG. 1 is shown, which shows a three-dimensional view of a groove and various elements therein according to some embodiments of the present inventive concept.

[0025] FIG. 5A to FIG. 5C They are respectively showing some embodiments of the present invention. FIG. 4A to FIG. 4C Graphs of isochoric, isothermal, and velocity vector diagrams of the embodiment shown in FIG.

[0026] Fig. 6A and Figure 6B is a diagram showing a flat outer channel with connecting fins according to some embodiments of the present inventive concept. DETAILED DESCRIPTION

[0027] The inventive concept will be described more fully below with reference to the accompanying drawings, in which illustrative embodiments of the inventive concept are shown. However, the inventive concept can be implemented in a variety of different forms and should not be construed as being limited to the embodiments set forth herein; on the contrary, these embodiments are provided so that the disclosure is comprehensive and complete, and the scope of the inventive concept will be fully conveyed to those skilled in the art. Throughout the specification, the same reference numerals represent the same elements. As used herein, the term "and / or" includes any and all combinations of one or more related listed items. Similarly, as used herein, the word "or" is intended to cover inclusive and exclusive "or" conditions. In other words, A or B or C includes any or all of the following alternative combinations suitable for a particular purpose: A alone; B alone; C alone; A and B alone; A and C alone; B and C alone; and A and B and C.

[0028] The terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the inventive concept. As used herein, unless the context clearly indicates otherwise, the singular forms "one", "an" and "the" are intended to also include plural forms. It should also be understood that when the terms "including" and / or "comprising" are used in this specification, the existence of stated features, integers, steps, operations, elements and / or parts is represented, but the existence or addition of one or more other features, integers, steps, operations, elements, parts and / or their groups is not excluded.

[0029] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as those commonly understood by those skilled in the art to which the inventive concept belongs. It should also be understood that terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant art and this specification, and should not be interpreted in an ideal or overly formal sense unless explicitly defined as such herein.

[0030] Reference will now be made in detail to various exemplary embodiments and alternative exemplary embodiments and the accompanying drawings. Each exemplary embodiment is provided by way of illustration and not as a limitation. It will be apparent to those skilled in the art that modifications and variations may be made without departing from the scope or spirit of the present disclosure and claims. For example, a feature shown or described as part of one embodiment may be used in conjunction with another embodiment to produce yet another embodiment. Therefore, the present disclosure is intended to include modifications and variations that fall within the scope of the appended claims and their equivalents.

[0031] As discussed above, power conversion equipment and electronic components are typically cooled conventionally using fan cooling, which uses forced air delivered by a fan to a heat sink to dissipate the heat generated by the components. In recent years, immersion-cooled electronics have used active elements to cool a fluid, and thereby cool the immersed electronics. The immersion fluid is typically pumped through an immersion container and then to a heat exchanger to remove heat from the fluid. However, the fluid must be pumped in a cycle, and a heat exchanger must be used to remove heat from the liquid.

[0032] Thus, some embodiments of the present inventive concept provide a passive fluid cooling device that cools the immersion fluid without the need for additional devices such as heat exchangers. As will be discussed below, embodiments of the present inventive concept take advantage of the fact that when the temperature of the fluid (e.g., dielectric) in the tank increases, the density of the fluid decreases. Thus, the heated fluid rises to the top of the tank and is cooled by circulating the fluid through external tubes (fluid cooling channels). This external tube arrangement allows heat to be dissipated without the use of any fans or pumps, which significantly improves the power usage effectiveness and efficiency of the immersed electronic components, as will be discussed below with reference to the accompanying drawings.

[0033] First reference Figure 1A and Figure 1B , the immersion tank 100 and the plurality of fluid cooling channels 110 according to some embodiments of the present inventive concept will be discussed. Figure 1A As shown in , the immersion tank 100 is provided with a plurality of fluid cooling channels 110 attached to its outer sidewalls. As used herein, "immersion cooling" is an information technology (IT) cooling practice by which IT components and other electronic devices (including entire servers, storage devices, and power equipment) are immersed in a thermally conductive but electrically insulating dielectric liquid or coolant. Traditionally, heat is removed from a system by circulating a relatively cool liquid in direct contact with the hot components and then circulating the now heated liquid through a cold heat exchanger. Unlike many other applications, water cooling cannot be used because ordinary water is conductive and can damage electronic components. Fluids suitable for immersion cooling have electrically insulating properties to ensure that they can safely come into contact with energized electronic components.

[0034] The immersion cooling tank 100 is a tank in which electronic components are arranged and filled with a large amount of dielectric liquid, in which the electronic components are immersed in the dielectric liquid. Therefore, various electronic components can share the same liquid. As used herein, liquid or fluid may include any liquid, fluid, oil, etc. that can be safely used to cool electronic equipment. The immersion cooling tank is completely sealed and can usually be opened from the top to maintain the IT equipment therein.

[0035] Unlike conventional immersion cooling systems, embodiments of the present inventive concept include one or more fluid cooling channels 110 attached to the immersion cooling tank 100 that allow the fluid in the immersion cooling tank 100 to circulate so that the fluid is cooled. Figure 1B 1 shows an embodiment of a fin tube (fluid cooling channel) 110 according to some embodiments of the present inventive concept. As shown in this figure, the tube 110 is provided with a plurality of fins attached to its exterior. The embodiments are not limited to Figure 1A and Figure 1B The specific number of fins shown in FIG. The external arrangement of the tubes 110 on the tank 100 allows the heat in the liquid to be dissipated without the use of any fans or pumps, which significantly improves the power usage effectiveness and efficiency of the immersed electronic components.

[0036] Specifically, Figure 1A and Figure 1B , tubes 110 are attached to the top and bottom of tank 100 so that fluid flows from tank 100 into tubes 110 at the top portion of tank 100 and flows back into tank 100 at the bottom of the tank. As the temperature of the fluid (e.g., dielectric) inside the tank increases, the density of the fluid decreases, causing the less dense fluid to rise to the top of tank 100. The fluid at the top of tank 100 filters / circulates through tubes 110 from the top of tank 100 and re-enters tank 100 at the bottom. The movement of the fluid through the external tubes 110 lowers the temperature of the fluid so that the fluid continues to cool the components located in the tank.

[0037] Reference now Figure 2A , as shown in the cross section of tank 100, components 130 and 135 are immersed in a coolant / fluid 120 (e.g., a dielectric liquid). As used herein, "component" refers to any electronic component that may generate heat and is customarily cooled in a conventional manner. For example, the components discussed herein may include uninterruptible power supplies (UPS) (e.g., single-phase and three-phase UPS), motor drives, or any other power conversion equipment. Although Figure 2A Only two components 130 and 135 are shown positioned in the slot 100, but embodiments of the inventive concept are not limited to this configuration. A single component or more than two components may be disposed in the slot 100 without departing from the scope of the inventive concept.

[0038] Heat associated with components 130 and 135 is transferred to the surrounding dielectric fluid (coolant 120). The temperature used in immersion cooling is determined by the maximum temperature at which the device being immersed can operate reliably. For servers, this temperature can range between 15°C and 65°C (59°F to 149°F), but can extend up to 75°C. The transfer of heat to the coolant causes the temperature of the coolant 120 near one or more components 120 to increase, which causes the density of the coolant 120 to decrease. The coolant 120 rises due to the buoyancy generated. The rising coolant 120 in the trough causes a circulating flow through the outer tubes 110. The heat in the fluid is dissipated by the fins ( Figure 1B ) is transferred to the surrounding air, the fins are used to increase the area available for heat transfer.

[0039] Figure 2B yes Figure 2A A perspective view of a cross section of the groove 100 in FIG. Figure 2B The x, y and z dimensions of the slot 100 are shown so that the positioning of components and other elements can be more accurately depicted.

[0040] FIG. 3A to FIG. 3C They are isochoric diagrams, isothermal diagrams and velocity vector diagrams, respectively, which illustrate various aspects of the inventive concept. Figure 3C The vector diagram in shows the circulating flow generated in the tank and through the tube.

[0041] Although the fluid cooling passage 110 is Figures 1A to 2B , but embodiments of the inventive concept are not limited to this configuration. For example, any type or shape of fluid cooling channels may be used without departing from the scope of the inventive concept. Thus, any embodiment of attaching one or more cooling channels to an immersion tank may be used. The fluid cooling channels may be, for example, radial disks with holes, fractal designs, etc. In addition, the fluid cooling channels may have one cross section or a combination of multiple cross sections: circular, rectangular, racetrack, etc. FIG. 4A to FIG. 4C Examples of various implementations of fluid cooling channels are shown in . The implementations are not limited to those fluid cooling channels shown in these figures, and these figures are provided by way of example only.

[0042] Specific reference FIG. 4A to FIG. 4C , wherein embodiments of hollow channels are shown for fluid cooling channels according to some embodiments of the present inventive concept. Figure 4A As shown in the figure, an external flat channel 115 is formed or attached to the side of the slot 100. In these embodiments, the passage inside the flat channel 156 guides the fluid to discharge heat to the surrounding air. The circulating flow in the slot 100 and in the external channel 115 is the same or similar to the circulating flow in the slot and the tube discussed above.

[0043] FIG. 5A to FIG. 5C In some embodiments according to the present invention, FIG. 4A to FIG. 4C 2 is a diagram of a velocity contour diagram, a temperature contour diagram, and a velocity vector diagram shown for the embodiment shown in FIG.

[0044] Fig. 6A and Figure 6B 1 and 2 are diagrams and cross-sectional perspective views of an embodiment including a flat channel and connecting fins, respectively. Fig. 6A As shown in FIG. 1 , the flat channel 115 has interconnected fins 116 (aluminum plates) to increase the surface area and thus enhance heat transfer, as shown in FIG. FIG. 3A to FIG. 3C as well as FIG. 5A to FIG. 5C In addition, Figure 6B A baffle 170 is shown for changing fluids or removing / adding components.

[0045] In some embodiments, the groove itself can be made to include features that direct the less dense fluid into the fluid cooling channels discussed herein. For example, in some embodiments, a portion of the top of the groove can be tilted downward to facilitate the fluid to enter the fluid cooling channels. In addition, additional features, such as baffles, can be installed inside the groove 100 to help guide the flow of the heated coolant 120, thereby enhancing the effectiveness of the groove 100. These baffles can be an integral part of the structure of the groove 100, or they can be installed separately. These baffles can be custom configured depending on the components or equipment to be cooled. The installed device can also have separate features that help guide the coolant 120 to improve cooling efficiency.

[0046] As discussed above, conventional immersion cooled electronic devices use active elements to cool the fluid and thereby the immersed electronic devices. The immersion fluid is typically pumped through an immersion container (tank) and then pumped to a heat exchanger to remove heat from the fluid. Embodiments of the inventive concept provide a passive fluid cooling device that reduces the power consumption of the immersion cooled device and expands the possible installation location options for IT equipment.

[0047] Specifically, immersion cooling reduces energy consumption by eliminating air cooling infrastructure including onboard server fans, CRACs, A / C compressors, air circulation fans, necessary ductwork, air handlers, and other active auxiliary systems (such as dehumidifiers). As discussed above, embodiments of the present inventive concept replace these traditional systems with liquid immersion technology, which provides a passive cooling system for the fluid in the tank. Therefore, embodiments of the present inventive concept require neither fans to circulate the dielectric liquid nor heat exchangers to cool the liquid.

[0048] It should be emphasized that the above-mentioned embodiments of the present disclosure are only possible examples of implementations set forth for a clear understanding of the principles of the present disclosure. Of course, it is not possible to describe every possible conceivable combination of components and / or methods, but a person of ordinary skill in the art will recognize that a variety of other combinations and arrangements are also possible. That is, various changes and modifications may be made to the above-mentioned embodiments without substantially departing from the spirit and principles of the present disclosure. All of these modifications and variations are intended to be included within the scope of the present disclosure and protected by the appended claims.

Claims

1. A passive fluid cooling system, comprising: An immersion cooling tank contains a volume of fluid; as well as A plurality of fluid cooling channels are attached to an outer sidewall of the immersion cooling tank, wherein the fluid flows through the plurality of fluid cooling channels on the outer sidewall of the immersion cooling tank to remove heat from a volume of the fluid.

2. The passive fluid cooling system according to claim 1, wherein: The plurality of fluid cooling channels are attached to the immersion cooling tank at a first portion and a second portion of the immersion cooling tank, wherein as the temperature of the fluid in the immersion cooling tank increases, the density of the fluid decreases, thereby causing the less dense fluid to rise to the top of the immersion cooling tank and flow into the plurality of fluid cooling channels to cool the fluid, and then flow back into the immersion cooling tank at a bottom portion of the immersion cooling tank.

3. The passive fluid cooling system according to claim 2, wherein: The flow of the fluid through the plurality of fluid cooling passages reduces the temperature of the fluid, thereby providing cooled fluid.

4. The passive fluid cooling system according to claim 3, wherein: The immersion cooling tank also includes electronic components located in the immersion cooling tank, and wherein the cooled fluid cools the electronic components located in the immersion cooling tank.

5. The passive fluid cooling system of claim 1, wherein: The fluid is caused to flow through the plurality of cooling channels without using a fan and / or a pump, thereby improving power usage efficiency.

6. The passive fluid cooling system of claim 1, wherein: The plurality of fluid cooling channels have a shape selected from one of the following: a fin shape, a radial disk shape, a fractal design, a rectangular shape, a racetrack shape, a circular shape, a flat channel shape, and combinations thereof.

7. The passive fluid cooling system of claim 1, wherein: The fluid is thermally conductive and electrically insulating.

8. The passive fluid cooling system of claim 7, wherein: The fluid has electrical insulating properties to ensure that the fluid can safely contact energized electronic components.

9. The passive fluid cooling system of claim 8, wherein: The fluid will not damage electronic components.

10. A passive cooling device comprising: An immersion cooling tank contains a volume of fluid; as well as A plurality of fluid cooling channels are attached to an outer sidewall of the immersion cooling tank, wherein the fluid flows through the plurality of fluid cooling channels on the outer sidewall of the immersion cooling tank to remove heat from a volume of the fluid.

11. The passive cooling device according to claim 10, wherein: The plurality of fluid cooling channels are attached to the immersion cooling tank at a first portion and a second portion of the immersion cooling tank, and as the temperature of the fluid in the immersion cooling tank increases, the density of the fluid decreases, so that the fluid with a smaller density rises to the top of the immersion cooling tank and flows into the plurality of fluid cooling channels to cool the fluid, and then flows back into the immersion cooling tank at a bottom portion of the immersion cooling tank.

12. The passive cooling device according to claim 11, wherein: The flow of the fluid through the plurality of fluid cooling channels reduces the temperature of the fluid, thereby providing cooled fluid.

13. The passive cooling device according to claim 10, wherein: The fluid is caused to flow through the plurality of cooling channels without using a fan and / or a pump, thereby improving power usage efficiency.

14. The passive cooling device according to claim 10, wherein: The plurality of fluid cooling channels have a shape selected from one of the following: a fin shape, a radial disk shape, a fractal design, a rectangular shape, a racetrack shape, a circular shape, a flat channel shape, and combinations thereof.

15. The passive cooling device according to claim 10, wherein: The fluid is thermally conductive and electrically insulating.

16. The passive cooling device according to claim 15, wherein: The fluid has electrical insulating properties to ensure that the fluid can safely contact energized electronic components.

17. The passive cooling device according to claim 16, wherein: The fluid will not damage electronic components.

18. An immersion cooling tank comprising: a plurality of fluid cooling channels attached to the outer sidewalls of the immersion cooling tank, wherein a volume of fluid flows through the plurality of fluid cooling channels on the outer side wall of the immersion cooling tank, thereby removing heat from the fluid; and Wherein the groove includes built-in features to direct the less dense fluid into the plurality of fluid cooling channels.

19. The immersion cooling tank of claim 18, wherein: The built-in feature includes a portion of a top of the slot being sloped downward to facilitate entry of the fluid into the plurality of fluid cooling channels.

20. The immersion cooling tank of claim 18, wherein: The built-in features include baffles located inside the groove to direct the flow of the fluid, the baffles are an integrally formed part of the groove, or the baffles are separately installed.

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