High heat capacity radiator

Abstract

A heat sink for cooling a heat-generating device, comprising: a housing comprising: a heat transfer block for receiving heat from the heat-generating device; and a sidewall extending from the heat transfer block, the heat transfer block and the sidewall collectively defining an interior volume for receiving coolant from outside the heat sink; and a plurality of heat pipes and / or vapor chambers, each heat pipe and / or vapor chamber extending from the heat transfer block within the interior volume. A cooled electronic system includes an electronic device that generates heat in use, the heat being dissipated from the electronic device through an exterior surface of the electronic device; and a heat sink having a heat transfer block mounted on an outer surface of the electronic device.

Description

Technical Field

[0001] The present disclosure relates to a heat sink and a cooling electronic system including the heat sink. A manufacturing method and / or an operating method of the heat sink and / or the cooling electronic system are also disclosed. Background Art

[0002] Computers, servers, and other devices used for data processing (known as information technology or IT) typically include printed circuit boards (PCBs). On these PCBs are devices known as integrated circuits (ICs), which may include central processing units (CPUs), application specific integrated circuits (ASICs), graphics processing units (GPUs), random access memory (RAM), etc. All of these electronic components or devices generate heat when used. In order to maximize the performance of IT, heat should be transferred away so that the contents are kept at an optimal temperature. These considerations also apply to other types of electronic devices or systems.

[0003] Typically, electronic components or devices used on or in IT are cooled using air. This typically includes some kind of heat sink with fins or the like placed in contact with the chip surface, either directly or with a TIM (thermal interface material) between the two components. In addition to the heat sink, a series of fans can pull air through the heat sink and transfer heat away from the electronic device. This type of heat sink is used in combination with another cooler, such as an air conditioner, in the facility where the electronic device is located (e.g., a server center). This cooling method is not particularly efficient, has a high operating cost, and uses a lot of space to manage the air used for cooling.

[0004] This method of cooling IT is used almost exclusively in mass-manufactured IT and server equipment. However, in recent times, the peak performance of heat-generating chips has been suppressed due to limitations in utilizing air-cooled equipment. As technology halves size every few years for the same performance (as exemplified in Moore's Law), the heat generated by chips increases as the footprint of components decreases.

[0005] In addition to (or as an alternative to) air cooling, a cooling plate may be positioned adjacent to a hot electronic component or device, such as described in International Patent Publication WO-03 / 107728A1. A cooling plate is a form of heat sink in which a coolant flows through the cooling plate and thereby carries away heat. Such a system can be more efficient than cooling methods that rely solely on air, but at the expense of increased complexity.

[0006] Another method for cooling IT uses immersion in a dielectric coolant (directly to the chip, partially immersed or fully immersed). International Patent Publication WO-2019 / 048864 describes a heat sink and heat sink arrangement for immersion cooling. A heat sink may be used to collect dielectric coolant adjacent to the equipment to be cooled and thus provide targeted cooling. Such a heat sink may have some similarities to a cold plate, except that the coolant may overflow or flow from the heat sink and thus cool additional equipment within the same external housing or chassis.

[0007] As the operating temperatures of electronic devices increase, it is desirable to achieve higher efficiency and / or heat transfer capabilities of heat sinks (cold plates, heat sinks for dielectric cooling or otherwise) for IT and other applications. This is a significant challenge. Summary of the invention

[0008] In this context, a heat sink according to claim 1 and a cooled electronic system according to claim 20 are provided. Further preferred and / or advantageous features are identified in the dependent claims and the remaining disclosure herein. A method of manufacturing and / or operating such a heat sink or a cooled electronic system having steps corresponding to the structural features described herein is also contemplated.

[0009] A heat sink having a heat pipe and / or a vapor chamber within an internal volume is provided, the internal volume also receiving a coolant fluid (typically a liquid, and typically without changing phase). The coolant is typically provided from outside the heat sink, and after passing through the internal volume, leaves the internal volume. The heat pipe and / or vapor chamber advantageously extends from a heat transfer surface or heat transfer block at the base of the heat sink. The heat pipe and / or vapor chamber are typically elongated, carrying heat from the base to an upper portion of the internal volume. This promotes efficient transfer of heat away from the heat transfer surface, resulting in a high thermal capacity.

[0010] In an embodiment, the heat sink has a housing including a heat transfer block and a sidewall extending from the heat transfer block. The heat transfer block and the sidewall together define an internal volume. The heat pipes typically each extend generally parallel to each other. Preferably, the heat pipes and / or vapor chambers extend substantially perpendicular to the plane of the heat transfer block and / or substantially parallel to the sidewalls. The heat transfer block may have a generally planar surface and / or may be generally planar in shape. This arrangement may allow a high density of heat pipes and / or vapor chambers to conduct from the heat transfer surface.

[0011] Heat sinks are typically tall because the length (and by extension, the side walls) of one, some or all of the heat pipes and / or vapor chambers is longer than a dimension of the base (i.e., the heat transfer surface), such as the width, length or diagonal size (if the base has a rectangular or square profile) or the radius or diameter (if the base has a polygonal, donut-shaped or circular profile).

[0012] In certain embodiments, the housing also has a cover, which can be remote from the heat transfer block. If the cover is arranged to seal the internal volume, the heat sink can be referred to as a cold plate. Embodiments without a cover, with a partial cover and / or a cover that does not seal the internal volume can be used for immersion cooling. In such embodiments, the heat sink can be configured to allow coolant to flow out of the internal volume and be used for direct cooling of other equipment.

[0013] The radiator may also include a coolant inlet for receiving coolant from outside the radiator into the internal volume, and a coolant outlet for allowing coolant to leave the internal volume and be transferred to the outside of the radiator. Typically, the coolant inlet is closer to the heat transfer block and the coolant outlet is farther away from the heat transfer block, but this may be reversed in embodiments. Where the coolant outlet is closer to the heat transfer block, the coolant outlet may include a tube that receives the coolant and carries the coolant upward away from the heat transfer block. This may facilitate collection of the coolant within the internal volume. Corresponding portions of the coolant inlet and / or coolant outlet (e.g., a connection port) may be removably coupled to the housing.

[0014] In some implementations, the coolant inlet may be disposed in the cover. This arrangement may mean that the coldest coolant enters the internal volume of the radiator away from the heat transfer surface, thereby maximizing the temperature difference along the heat pipe and making the heat transfer more efficient. In addition, the flow can be balanced so that the flow permeates the entire length of the heat pipe. The coolant can flow from the coolant inlet to the base, and then flow from the base (via the heat pipe and / or the vapor chamber) to the outlet. Optionally, the coolant outlet may be disposed in the cover. The coolant inlet may be in line with the heat pipe and / or the vapor chamber. Therefore, coolant contact with the surface area of ​​the heat pipe can be maximized without the need for surface extension fins on the heat pipe. In this case, the coolant inlet is in the center of the cover, which can also allow a more balanced or more evenly distributed flow of the coolant within the internal volume.

[0015] In a cooling plate implementation, a manifold can cause coolant to flow from a coolant inlet to multiple locations at the base of multiple heat pipes and / or vapor chambers. In other words, the manifold can cause the incoming (and therefore coldest) coolant to flow directly to multiple locations at the base of the heat pipes and / or vapor chambers. This can promote efficient flow of coolant within the cooling plate and efficient cooling. These locations can be symmetrically arranged on the base of the heat pipes and / or vapor chambers (and / or in a plane parallel to the heat transfer block, or at least at the surface of the heat transfer block close to the heat pipes). In some embodiments, the housing can define the manifold and / or the manifold can be integral with the housing.

[0016] The structure of the housing and / or sidewalls may be modular. For example, the sidewalls may be formed from modules, each of which defines a portion of the sidewall. The modules may then be stacked (on a heat transfer block) to define an internal volume.

[0017] Advantageously, the heat pipes and / or vapor chambers are arranged in a regular pattern. This may be particularly applicable when the heat pipes are used in a beneficial pattern, with the angle between the center of each heat pipe and one or more corresponding adjacent heat pipes being about 60 degrees (e.g., 45 to 75 degrees, 55 to 65 degrees, 57 to 63 degrees, 58 to 62 degrees, or 59 to 61 degrees).

[0018] Heat pipes and / or vapor chambers may all be identical. However, in certain embodiments, heat pipes and / or vapor chambers are not identical, in particular, do not have the same cross-sectional size and / or shape (a cross section taken through the extended dimension). This can improve the compactness of heat pipes and / or vapor chambers. For example, heat pipes and / or vapor chambers can be divided into two groups with cross-sectional areas that are different from each other (but optionally, the same in other ways). The two groups of heat pipes can be interspersed (or alternated) with each other. This can allow for tighter spacing of heat pipes and / or vapor chambers, so that more surface areas of heat pipes and / or vapor chambers can be arranged in the internal volume. More than two groups of heat pipes or vapor chambers can be considered, each group having a different cross-sectional area. The cross-sectional shape of the heat pipes or vapor chambers (e.g., in each group) can be the same or different. Possible cross-sectional shapes include circular, polygonal (especially, rectangular or hexagonal) or fin-shaped (especially for vapor chambers). Groups of heat pipes and / or vapor chambers that differ only by shape can also be considered.

[0019] The transfer of heat to the coolant can occur in different ways. In one embodiment, the heat pipes and / or vapor chambers are welded or metallurgically joined to the heat transfer block. Additionally or alternatively, heat can be conducted upward along the sidewalls between the heat pipes (i.e., away from the heat transfer block). Each heat pipe and / or vapor chamber can be positioned within a corresponding hole in the heat transfer block.

[0020] In another implementation, the heat transfer block may include (internally) a vapor chamber. More preferably, the heat pipes and / or vapor chambers extending from the heat transfer block may be integral with the vapor chamber of the heat transfer block (i.e., the vapor chamber within the heat transfer block may extend within the heat pipes and / or vapor chambers extending from the heat transfer block).

[0021] Baffles within the internal volume can each direct coolant flow toward or away from one or more corresponding heat pipes and / or vapor chambers. Particular implementations use generally planar baffles. These can be distributed vertically in the internal volume (i.e., in a direction away from the heat transfer block). Adjacent baffles can then cover different portions of the cross-sectional area of ​​the internal volume, for example alternating between different or opposing side walls. Thus, this can allow coolant to flow through multiple heat pipes and / or vapor chambers. In embodiments, insulating material around the outside of the housing can also help transfer heat via the coolant and away from the radiator and its surroundings.

[0022] A heat sink may be configured to cool a portion of an electronic system, such as a computing module. An electronic device, such as a computer chip or circuit, may generate heat when in use, wherein the heat is dissipated through an outer surface. A heat transfer block of the heat sink may be mounted on an outer surface of the electronic device, for example, such that an outer surface of the heat transfer block is coplanar with an outer surface of the electronic device. Heat may be efficiently transferred away from the electronic device and to a coolant within the heat sink. The system may have a chassis, wherein the electronic device and the heat sink are located within the chassis.

[0023] The outer surface of the electronic device has a heat distribution during use (e.g., certain areas may be hotter while other areas may be cooler). Optionally, the coolant inlet of the heat sink and / or the center of the heat transfer block are aligned with (e.g., directly adjacent to) the hottest part of the heat distribution.

[0024] In addition to the electronic device cooled by the heat sink, there may be other electronic devices to be cooled in the chassis. The coolant flowing out of the heat sink can be directed to flow through one or more of the other electronic devices, in particular to cool one or more of the other electronic devices.

[0025] The heat exchanger can receive coolant from the radiator and transfer heat from the coolant to the radiator. A tube arrangement can carry coolant between the heat exchanger and the radiator. A pump (e.g., coupled within the tube arrangement) can flow coolant between the heat exchanger and the radiator. The heat exchanger can be located inside or outside the chassis. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The present disclosure may be practiced in many ways and a preferred embodiment will now be described by way of example only and with reference to the accompanying drawings, in which:

[0027] Figure 1 depicts an isometric view of a heat sink mounted on an electronic device including at least one component to be cooled according to a first embodiment;

[0028] Figure 2 Shows Figure 1 A side view of an embodiment of the invention;

[0029] Figure 3 Shows Figure 1 The implementation method is along Figure 2 A plan cross-sectional view of section AA shown in FIG.

[0030] Figure 4 Shows Figure 1 A front view of an embodiment of the invention;

[0031] Figure 5 Shows Figure 1 The implementation method is along the Figure 4 A side cross-sectional view of section BB shown in FIG.

[0032] Figure 6 Shown according to Figure 1 An isometric view of only the heat sink of an embodiment of ;

[0033] Figure 7 Depicted Figure 6 The plan view of the radiator;

[0034] Figure 8 Depicted Figure 6 A side view of a radiator;

[0035] Fig. 9 Depicted Figure 6 A front view of a radiator;

[0036] Fig.10 Shows Figure 6 An exploded isometric view of the radiator;

[0037] Fig.11 Shown according to Figure 1 An isometric view of only the electronic components of an embodiment of ;

[0038] Fig.12 Depicted Fig.11 A plan view of the electronic components;

[0039] Fig.13 Depicted Fig.11 A side view of an electronic component;

[0040] Fig.14 depicts an isometric view of a heat sink according to a second embodiment;

[0041] Fig.15Shows Fig.14 A side view of an embodiment of the invention;

[0042] Fig.16 Shows Fig.14 An exploded isometric view of the radiator;

[0043] Fig.17 shows an exploded isometric view of a heat sink according to a third embodiment;

[0044] Fig.18 Shows Fig.17 A side view of an embodiment of the invention;

[0045] Fig.19 Shows Fig.17 The implementation method is along the Fig.18 A plan cross-sectional view of section DD shown in FIG.

[0046] Fig. 20 shows an exploded isometric view of a heat sink according to a fourth embodiment;

[0047] Fig.21 Shows Fig. 20 A front view of an embodiment of the invention; and

[0048] Fig. 22 Shows Fig. 20 The implementation method is along the Fig.21 Side cross-sectional view of section FF shown in FIG.

[0049] All the drawings are schematic in nature. Identical components are illustrated using the same reference numerals in different drawings. DETAILED DESCRIPTION

[0050] As discussed above, the present disclosure is discussed with respect to a broad heat sink. The heat sink may include a cooling plate, an open cooling plate (a cooling plate that enables coolant to flow out of the cooling plate), and a heat sink for immersion cooling, such as described in WO-2019 / 048864. The cooling plate may also be applied to other types of heat sinks. The heat sink includes a heat transfer block, which is typically coplanar with a heat source (an electronic device, such as a packaged integrated circuit or collection of components that can be mounted on a circuit board).

[0051] The heat pipes are secured into the heat transfer block. The heat pipes are typically oriented perpendicular to the plane of the heat transfer block and / or heat source. This can enable the density of heat pipes conducting from the space occupied by the heat source to be increased. Heat pipes are typically elongated and can be tall, especially relative to the size of the heat transfer block heat sink surface. Using heat pipes in this manner can facilitate significant heat removal from a small area. For example, 600W of thermal energy can be removed from a square flat heat transfer block with a heat sink surface size of 55mm x 55mm. As will be discussed below, the heat pipes are densely packed.

[0052] The heat pipes can be welded or metallurgically joined to the heat transfer block. This can minimize the distance between the heat source and the heat pipes while allowing heat to be conducted along the walls between the heat pipes perpendicular to the heat source, through the curled ends of the heat pipes which may be inefficient.

[0053] The use of (segmented) modular housings can also be beneficial. In particular, different heat pipe lengths can be used for different cooling requirements, or the heat sink housing height can be changed according to space requirements (e.g. in an external chassis). In principle, the housings can be stacked to any desired height.

[0054] Before discussing specific embodiments of a heat sink according to the present disclosure, the present disclosure will first be discussed in more general terms. In these terms, it can be considered that there is a heat sink for cooling a heat generating device, the heat sink comprising: a housing, the housing comprising: a heat transfer block for receiving heat from the heat generating device; and a side wall extending from the heat transfer block, the heat transfer block and the side wall together defining an internal volume for receiving a coolant from outside the heat sink; and a plurality of (elongated) heat pipes, each heat pipe extending from the heat transfer block within the internal volume (e.g., extending in parallel). Thus, the heat pipes extend into the internal volume and are not merely placed within the heat transfer block. This enables more heat pipes to be arranged within the heat sink than previously considered. In some implementations, only a small portion (up to or less than 1%, 2%, 5%, 7.5%, 10%, or 15% of the length of the heat pipe) may be in contact with the heat transfer block.

[0055] Although the term heat pipe is used herein, it should be understood that the terms "heat pipe" and "vapor chamber" are often used to describe similar types of devices having different shapes. Heat pipes typically have a tubular (or finned) shape, while vapor chambers are typically flatter (e.g., more planar and / or fin-like). Additional and / or alternative uses of vapor chambers will be discussed further below.

[0056] The side wall may be formed from a plurality of modules. Each module may then define a portion of the side wall. For example, the modules may then be stacked on a heat transfer block to define an internal volume. The coolant is typically a liquid (and preferably the radiator is configured to maintain the coolant in that phase). Preferably, a plurality of heat pipes are welded or metallurgically joined to the heat transfer block.

[0057] In another aspect, a cooling electronic system may be considered, comprising: an electronic device that generates heat during use, the heat being dissipated from the electronic device through an outer surface of the electronic device; and a heat sink as disclosed herein, the heat sink having a heat transfer block mounted on the outer surface of the electronic device. For example, the outer surface of the heat transfer block may be coplanar with the outer surface of the electronic device. The system may also include a chassis, and the electronic device and the heat sink are typically located within the chassis.

[0058] Specific embodiments will now be described in detail. Further reference will be made to this broad sense of the disclosure again later below.

[0059] Now refer to Figures 1 to 5 , depicting a heat sink 100 according to a first embodiment mounted on an electronic device 200 including at least one component to be cooled, showing: Figure 1 Isometric view in ; Figure 2 Side view in; Figure 3 Plane cross-section diagram in ; Figure 4 ; and Figure 5 Side cross-section view of .

[0060] The heat sink 100 includes: a bottom plate 1; a spring device 2; a housing 3; a top plate (cover) 4; and tie rods 5. The heat sink 100 also includes: an inlet device 6; and an outlet device 7. Disposed within the heat sink 100 are: a heat pipe 8; and a baffle 9, which defines a gap 10, which will be discussed further below. The heat sink 100 is used for immersion (dielectric) cooling, rather than a cold plate with a closed coolant (water) circuit.

[0061] The housing 3 is made of stacked components. Each component (module or section) has the same size and shape, and by stacking a specific number of housing components, the height of the housing 3 can be set. The outer shape of the housing 3 is generally a rectangular parallelepiped, but this is not necessary. The housing 3 defines an internal volume for collecting coolant, which will be discussed further below. Therefore, using different numbers of sections for the housing 3 can change the height of the radiator 100, and more particularly, its internal volume can be changed, for example, to accommodate different cooling requirements or space constraints. Typical radiators are relatively flat, and the height dimension is generally smaller than the length and / or width. In contrast, the radiator 100 has a relatively tall shape: the height dimension (of the housing 3) is larger than the length dimension and / or width dimension (and possible diagonal length) of the base plate 1.

[0062] In this embodiment, the sections of the housing 3 are made of plastic. This can thermally (and electrically) insulate the housing, thereby improving thermal performance. In particular, the housing 3 can minimize heat transfer to the surrounding environment and thus improve the efficiency of the heat sink. The top plate 4 can be used to increase the rigidity of the plastic stacked sections of the housing 3. The sections are fixed together using tie rods 5.

[0063] The electronic device 200 includes at least one (and typically more than one) electronic component, such as a packaged integrated circuit. The base plate 1 is mounted to the electronic component using a spring arrangement 2 (typically comprising springs and screws) to provide a force on a thermal interface material (TIM, not shown) between the base plate 1 and the electronic device 200. Therefore, the base plate 1 can be considered a heat transfer block because it is configured to receive heat from the electronic device 200 (by conduction). The base plate 1 has a generally planar rectangular or square shape.

[0064] As discussed above, the heat sink 100 is designed for immersion cooling (particularly, using a dielectric), and other components in the same chassis (not shown) as the heat sink 100 and the electronic device 200 are cooled by the same coolant flowing through the heat sink 100. In the illustrated embodiment, the coolant inlet 6 is at the top of the housing 3, and the coolant outlet 7 is at the bottom of the housing 3. Since the coolant enters through the coolant inlet 6 farthest from the heat source, the temperature difference along the heat pipe 8 can be maximized. In this example, the outlet 7 includes an upward portion 7A, which is configured to raise the dielectric coolant so that it overflows the outlet 7 at the highest point possible (away from the base plate 1). This is intended to always keep the heat sink housing 3 full of coolant. The overflowing dielectric coolant can then cool additional components, such as components on the substrate of the electronic device 200 (which will be discussed further below).

[0065] Special reference Figure 3 ,exist Figure 3 It is shown in Figure 1 The implementation method of Figure 2 FIG. 2 is a plan cross-sectional view of section AA (shown in FIG. 2 ). Section AA is cut directly through the shell segment 3 and the heat pipe 8. The figure depicts 49 heat pipes, with a spacing of 6.8 mm between each heat pipe and a 60 degree pitch. The staggered pattern (due to the pitch angle) can force the coolant to spread across all the heat pipes 8. The shell segment 3 is advantageously shaped on its interior to conform to the outer shape of the heat pipe 8, which can prevent the coolant from bypassing the heat pipe. In the depicted embodiment, the heat pipes 8 all have the same shape and cross-sectional area, but this is not considered necessary. The cross-sectional form of the heat pipe 8 is believed to provide a high surface contact area at the interface between the coolant fluid and the heat pipe 8 as the flow moves around a circular path.

[0066] The pattern shown about the heat pipe 8 is considered to be one of the densest patterns that can be achieved while still maintaining sufficient coolant flow and ensuring sufficient contact area between the coolant and the heat pipe 8. The pattern can also prevent direct flow through the heat pipe 8 and / or a straight fluid flow from the inlet 6 to the outlet 7. On the contrary, turbulence is caused throughout all the heat pipes 8, thereby ensuring uniform contact, and any coolant can also be prevented from bypassing any heat pipe in the heat pipe 8. This configuration is suitable for cooling electronic devices 200 with high heat output. Compared with the heat sink with a horizontal orientation of densely packed heat pipes, this configuration has been found to have superior thermal performance. The vertical orientation of the heat pipe 8 in this embodiment (that is, substantially perpendicular to the base plate 1) allows the use of significantly more heat pipes 8. It has been found that a large number of heat pipes are expected for thermal performance. Compared with the 49 heat pipes 8 of the embodiment shown, orienting the heat pipe horizontally will allow about 6 heat pipes.

[0067] Also refer to Figure 5 , showing Figure 1 The embodiment of the invention is along the vertical section BB ( Figure 4 1 and 2). This shows the path taken by the coolant from the inlet 6 to the outlet 7 and through the heat pipe 8. The figure also shows that the heat pipe is installed in the base plate 1 by welding to the hole 12 formed in the base plate 1. The shape of each hole 12 in the base plate 1 matches the shape of the corresponding heat pipe 8 as closely as possible, so that the least solder is used. This can reduce thermal resistance and improve performance. Another desired parameter to be controlled is the depth to which each heat pipe 8 is inserted into the base plate 1 (the depth can be controlled by the height of the corresponding hole 12). Each heat pipe 8 has thicker metal at one end (tip). Specifically, one end of the heat pipe 8 is sharp (curled or tapered) and the other end is round. The sharp tip of the heat pipe 8 is inserted into the hole 12. By configuring the depth of each hole 12, sufficient contact between the heat pipe 8 and the base plate 1 can be set to optimize the heat transfer in the vapor from the base plate 1 to the inside of the heat pipe 8. The round end of each heat pipe 8 is inserted into the corresponding hole 13 formed in the top plate 4.

[0068] Baffles 9 are stacked horizontally along the vertical heat pipes 8. Baffles 9 are advantageously confined between each section of the housing 3 for ease of assembly. Baffles 9 create a horizontally oriented chamber (the chamber is elongated perpendicular to the direction of elongation of the housing 3) that allows the coolant to flow horizontally through the heat pipes 8. Each baffle 10 has a gap 10 along its side to allow the coolant to pass vertically to the next chamber. The gaps alternate the sides (i.e., from left to right) to force the coolant to follow a "zigzag" flow pattern along the elongated length of the heat pipe 8. This can allow the coolant to pass through the same heat pipe 8 multiple times, and thus optimize heat transfer by utilizing the full length of the heat pipe 8 (i.e., forcing the dielectric coolant to contact as many heat pipes 8 as possible along its full length). Alternating the sides of the gaps 10 can be achieved simply by stacking the same baffles 9 in alternating positions.

[0069] Now refer to Figures 6 to 9 , depicting only the heat sink 100 of the embodiment discussed above, shows: Figure 6 Isometric view in ; Figure 7 Floor plan in ; Figure 8 ; and Fig. 9 All features shown in these figures have been discussed above and therefore will not be described in detail again here.

[0070] Next, refer to Fig.10 , showing Figure 6 Exploded isometric view of a radiator of FIG. Here, the baffle 9 and the gap 10 are shown from different angles. In addition, the structure of the coolant inlet 6 is shown, including the housing aperture 14 and the tube arrangement 6A removably coupled to the aperture 14. Likewise, the structure of the coolant outlet 7 is shown, including the housing aperture 15 and the upward portion 7A removably coupled to the aperture 15.

[0071] It will be understood that the radiator 100 and the electronic device 200 are arranged in a chassis (not shown). In the immersion cooling method, according to the embodiment shown, the chassis is configured to collect the coolant flowing out from the radiator (before or after collection, the coolant can flow through other components on the electronic device 200 or other places in the chassis). A pump usually in the chassis causes the coolant to flow in the chassis, although the convection flow of the coolant can additionally or alternatively cause the movement of the coolant. A heat exchanger can be provided, preferably a heat exchanger is provided in the chassis to transfer heat from the dielectric coolant to the secondary coolant (e.g., water or a water-based coolant). The heat exchanger can also be configured to keep the dielectric (primary) coolant in a single (liquid) phase. More details about such an arrangement are provided at least in WO-2019 / 048864, which is incorporated by reference as a whole.

[0072] Referring again to the broad sense of the present disclosure discussed above, additional optional and / or advantageous features may be considered. For example, the heat transfer block may have a generally planar surface and / or be generally planar. In some embodiments, the housing further comprises a cover. Optionally, the housing is made of a thermally insulating material.

[0073] In an embodiment, the plurality of heat pipes may extend substantially perpendicular to the plane of the heat transfer block. Additionally or alternatively, the heat pipes may extend substantially parallel to the side wall (of the housing).

[0074] Preferably, at least one (more preferably some and optionally all) of the plurality of heat pipes has a length greater than a dimension of the heat transfer block (e.g., one or more of the width, length, diagonal size, radius, diameter of the heat transfer block).

[0075] The radiator may also include: a coolant inlet for receiving coolant from outside the radiator into the internal volume; and a coolant outlet for allowing the coolant to leave the internal volume and pass to the outside of the radiator. If the coolant inlet is at a portion of the housing close to the heat transfer block, the coolant outlet is typically at a portion of the housing far from the heat transfer block, and conversely, if the coolant outlet is at a portion of the housing close to the heat transfer block, the coolant inlet may be at a portion of the housing far from the heat transfer block. In the latter case, the coolant outlet may include a coolant configured to receive a portion of the internal volume that is relatively close (close) to the heat transfer block, and to carry or guide the received coolant (relatively) away from the heat transfer block (in a direction perpendicular to the plane of the heat transfer block, for example, the direction may be upward or vertically). The coolant can then leave the radiator at such a remote location. Advantageously, the coolant inlet and / or the coolant outlet each include a connection port that is removably coupled to the housing (e.g., by push-fit or screw connection).

[0076] A plurality of heat pipes may be arranged in a regular pattern. For example, the angle between the center of each heat pipe and one or more corresponding adjacent heat pipes may be 60 degrees.

[0077] In an embodiment, each of the plurality of heat pipes is positioned within a respective aperture in the heat transfer block.The side walls may be arranged such that heat is conducted along the side walls between the heat pipes, perpendicular to the heat transfer block.

[0078] Advantageously, the heat sink further comprises one or more baffles arranged within the internal volume to direct coolant flow toward, away from or through at least one of the plurality of heat pipes. Preferably, the one or more baffles comprise a plurality of generally planar baffles distributed within the internal volume in a direction away from the heat transfer block. In this case, adjacent baffles may cover different portions of the cross-sectional area of ​​the internal volume. For example, adjacent baffles may alternate between different or opposing side walls. In any case, the baffles may be arranged to direct coolant flow through the plurality of heat pipes.

[0079] With respect to the cooling electronic system discussed above, additional details may be considered. For example, the system may also include a heat exchanger configured to receive coolant from the radiator and transfer heat from the coolant to a heat dissipation fluid (e.g., a secondary coolant). Optionally, the pipe arrangement may be arranged to transport the coolant between the heat exchanger and the radiator. The heat exchanger may be located inside or outside the chassis. Additionally or alternatively, a pump may be provided to flow the coolant. The pump may be arranged to flow the coolant between the heat exchanger and the radiator. The pump may be located inside or outside the chassis.

[0080] Preferably, the electronic device is a first electronic device, and the cooling electronic system further comprises a second electronic device. The second electronic device may be arranged such that the coolant flowing out of the heat sink flows through or passes the second electronic device (for cooling the second electronic device).

[0081] Further reference will be made again below to the broad sense of the present disclosure.First, additional details of specific embodiments and other arrangements will be considered.

[0082] Now refer to Figures 10 to 13 , which depicts only the electronic device 200 of the embodiment discussed above, showing: Fig.11 Isometric view in ; Fig.12 ; and Fig.13 1. Some of the features shown in these figures have been discussed above, but these features will now be considered in more depth. Electronic device 200 includes: a substrate (or circuit board) 19; a main processor chip 16; a chiplet 17; and auxiliary components 20. This is merely an example of an electronic device that may be cooled by heat sink 100 and is not to be considered limiting.

[0083] The main processor 16 is at the center of a substrate or PCB 19, with four chiplets 17 mounted in close proximity around the main processor 16. Such close proximity is becoming more common because it can increase the communication speed between the chiplets 17 and the main processor 16. In this example, the main processor 16 and the chiplets 17 are coplanar and can be cooled by a heat sink 100 having a base plate 1 with a flat lower surface. In other examples, the chips 16, 17 can be at different heights. The base plate 1 of the heat sink 100 can then be shaped to conform to the contours of the chips 16, 17.

[0084] A socket 18 is provided on the electronic device 200, on which the heat sink 100 can be mounted. The actual socket 18 may have a slightly different appearance than that shown in the drawings. The spring device 2 on the heat sink 100 may be mounted directly into the socket 18. As discussed above, the dielectric overflow from the coolant outlet 7 of the heat sink 100 may be utilized to cool the auxiliary electronic components 20 on the substrate 19.

[0085] In some embodiments, multiple heat sinks 100 may be arranged in a single chassis, such as in a grid. As an example, 6 to 12 heat sinks 100 may be arranged in the same chassis.

[0086] Alternative designs of the heat sink are also possible. For example, the dielectric coolant inlet may be provided at the base of the heat sink, and the coolant outlet may overflow from the top of the heat sink. Fig.14 , depicts an isometric view of a heat sink according to a second embodiment consistent with this method. Many of the details are the same as the first embodiment described above, so for the sake of simplicity, these details will not be repeated. The heat sink 100' has a dielectric coolant inlet 26 toward the base or bottom and a coolant outlet 27 toward the top (i.e., away from the base). It has been found that the cooling performance of the heat sink is better (although perhaps only slightly better) than the cooling performance of the heat sink of the first embodiment. Also refer to Fig.15 and Fig.16 ,exist Fig.15 It is shown in Fig.14 A side view of an embodiment of the present invention, and Fig.16 It is shown in Fig.14 It will be seen from these figures that other details of the heat sink 100' are substantially the same as those of the heat sink 100 of the first embodiment.

[0087] Next, refer to Fig.17, shows an exploded isometric view of a heat sink 100" according to a third embodiment. It will be seen from these figures that many of the details of the heat sink 100" are the same as those of the heat sink 100 of the first embodiment, and so for the sake of simplicity these details will not be repeated. However, this embodiment uses vapor chambers 8A in place of heat pipes. The vapor chambers 8A operate in a manner similar to heat pipes, but their external form is fin-like rather than rib-like. The use of fin-like vapor chambers 8A (i.e., flat heat pipes) can spread heat away from the center of the heat sink. This can better optimize heat transfer through the base than using only heat pipes as considered above.

[0088] As mentioned above, the design of this embodiment is shown to be similar to the first embodiment with a dielectric coolant inlet at the top of the radiator and a coolant outlet at a lower height, but with an upward portion configured to raise the dielectric coolant before overflowing. However, it will be appreciated that the configuration of this design can be easily adjusted to match the second embodiment in terms of the dielectric coolant inlet and coolant outlet.

[0089] Also refer to Fig.18 and Fig.19 ,exist Fig.18 It is shown in Fig.17 A side view of an embodiment of the present invention, and Fig.19 It is shown in Fig.17 The implementation method is along the Fig.18 DD is shown in plan view. The different internal structure of this heat sink design can be seen. However, the operation is substantially the same as described above with reference to the first embodiment.

[0090] In another design, the base plate may include a vapor chamber. In addition, the heat pipe (i.e., fin-shaped vapor chamber) may be made of the same vapor chamber as the base. The role of the heat sink can be considered to be to diffuse the thermal energy from a small concentrated heat source to a much larger area, over which the heat can flow out to the surrounding fluid by convection. As discussed above with reference to the previously described design, the heat is initially transported a short distance from the heat source by conduction within the solid metal base before being efficiently transported by a large number of heat pipes. This can provide a large wetted area for convection with the surrounding fluid. It is conceivable that the thermal performance of the heat sink can be improved by minimizing the internal thermal resistance of the heat sink. Adaptation of the base plate can achieve this additional goal, as will be discussed below.

[0091] Compared to the previously described embodiments, the thermal performance of high power density devices can be increased by better spreading the heat laterally (i.e., in the plane of the heat source or baseplate). This can also enable a greater number of heat pipes (and / or vapor chambers) to participate in the heat transfer process than the previously described designs. Using a solid metal base to achieve this lateral heat spreading may create significant thermal resistance, which is detrimental to overall performance.

[0092] Now refer to Fig. 20 , shows an exploded isometric view of a heat sink 100 ″′ according to such a fourth embodiment. Also referring to Fig.21 and Fig. 22 , Fig.21 A front view of the embodiment is shown, and Fig. 22 An embodiment is shown along Fig.21 FF shown in FIG. 1 . As shown, an integrated base plate and heat pipe structure 21 is provided, which includes at least one vapor chamber (preferably forming a single vapor chamber structure). Therefore, the integrated structure 21 uses the same two-phase heat transfer process as previously described for the interior of the heat pipe to help spread the heat laterally (in the plane of the heat source). The integration of the base plate and the heat pipe into a single structure 21 provides a continuous and closed internal cavity, thereby performing both the vapor chamber function and the heat pipe function. Therefore, the thermal performance of the design is improved compared to the heat flow through the solid metal interface between the base plate and the heat pipe or even between the vapor chamber and the heat pipe.

[0093] It can also be seen that the outer profile of the heat sink 100'" will exhibit approximately the same shape and size as the "heat pipe heat sink" design. The surface area exposed to the surrounding fluid will be the same, as will the pressure drop produced to the surrounding fluid.

[0094] As with the third embodiment, the design of the fourth embodiment is shown to be similar to the first embodiment with a dielectric coolant inlet at the top of the heat sink and a coolant outlet at a lower height, but with an upward portion configured to raise the dielectric coolant before it overflows. However, it will be appreciated that the configuration of this design can be easily adjusted to match the second embodiment in terms of the dielectric coolant inlet and coolant outlet.

[0095] Returning to the general meaning of the present disclosure, it will be understood that heat pipes and / or vapor chambers may be used, rather than just heat pipes. In other words, where the term heat pipe has been used above, the heat pipe may be replaced by a vapor chamber.

[0096] Although specific embodiments have now been described, the skilled person will appreciate that various modifications and substitutions are possible. As previously discussed, although the illustrated embodiment is a radiator for immersion cooling, in which the outflowing coolant is used to cool other components within the same chassis, an alternative closed-loop cooling plate device may be used. Although dielectric coolants are preferably used for immersion cooling, the closed-loop cooling plate device may use different coolants, particularly water or a water-based coolant. The coolant used is preferably single-phase (in other words, the radiator is designed to keep the coolant in a liquid phase), but a two-phase coolant may alternatively be used (so that the radiator is designed to boil the coolant). For the cooling plate, the flow of the coolant is beneficially balanced so that the flow permeates the entire length of the heat pipe. The heat exchanger and / or pump for the cooling plate may be disposed within an outer chassis (where the radiator and electronic equipment are positioned) or outside the chassis. The heat exchanger may transfer heat from the coolant flowing through the cooling plate to another coolant fluid (which may be a liquid or a gas).

[0097] In a closed cooling plate (or other embodiments), the locations of the coolant inlet and coolant outlet can vary. For example, in one implementation, the coolant inlet can pass through the cover (e.g., the center of the top surface of the cover) approximately opposite the hottest part of the device being cooled. The coolant outlet can pass through the cover on one side of the top surface of the cover. In a specific implementation, the coolant inlet can be in line with the heat pipe, which can achieve maximum contact between the coolant fluid and the heat pipe surface area along the height dimension without the need for fins extending the heat pipe surface.

[0098] Typically, the coolant inlet does not have to be located at the top of the housing, and the coolant outlet does not have to be located at the bottom of the housing. In fact, the coolant inlet and coolant outlet of the embodiment shown in the drawings (and discussed above) can be reversed. In this case, the upward portion 7A can be omitted or replaced by a tube. The use of removable couplings in the coolant inlet and coolant outlet enables these connections to be directly changed. In addition, for a radiator that is not a cooling plate, the coolant outlet does not need to have an associated tube. For example, the coolant outlet can simply include a hole or orifice in the housing or top plate (cover). The coolant can only overflow the housing. In some cases, a top plate may not be provided, and the coolant outlet may include an orifice formed by the top of the housing. Multiple coolant outlets can be provided, for example, the multiple coolant outlets can be symmetrically arranged to promote equal flow distribution within the internal volume, or according to the heat distribution of the electronic components below, to produce a higher flow rate on a specific part of the heat transfer surface than other parts. Multiple coolant inlets can be used, but this becomes more complicated.

[0099] Different configurations and / or arrangements of heat pipes are possible. For example, the shape and / or size of the heat pipes may be different from those shown. In addition, heat pipes of different shapes and / or sizes may be arranged in the same radiator. For example, an array of heat pipes with two different diameters can minimize turbulence and provide a larger heat pipe surface area compared to a single array. The cross-sectional shape of the heat pipe (perpendicular to the direction of elongation) can be circular, rectangular, hexagonal or other shapes. In some embodiments, two or more different types of heat pipes (each type having a specific shape and size) can be used. The heat pipe pitch spacing and / or angle can be changed, particularly to optimize thermal performance, particularly depending on the size and shape of the heat pipes used.

[0100] In another option, the housing (container) in which the heat pipe and coolant fluid are included can form its own manifold, directing flow from the inlet to one or more outlet ports. The manifold can optionally combine the flow from the outlet ports into a single outlet.

[0101] The heat pipes are preferably welded into the heat transfer block, but they may be metallurgically joined in other ways. This can minimize the distance between the heat source and the heat pipes while allowing heat to be conducted along the walls between the heat pipes perpendicular to the heat source and bypassing inefficient curled ends of the heat pipes.

[0102] The housing is preferably formed from plastic, but other materials may be used, particularly those that are thermally insulating. Additionally or alternatively, thermal insulation around the housing may be used to minimize heat transfer to the surrounding environment.

[0103] The use of baffles within the interior volume of the heat sink is advantageous, and other baffle patterns may be provided (eg, flow may be directed toward a particular heat pipe if it is working comparatively harder due to the thermal profile of the electronic device being cooled). Alternatively, no baffles may be used.

[0104] As mentioned above, other versions would include a dielectric coolant inlet at the base and a coolant outlet that overflows from the top. This could also be converted into a cold plate with a closed water-based coolant circuit if hoses were secured to the inlet and outlet.

[0105] Embodiments using only heat pipes and only vapor chambers have been shown. However, it will be understood that heat pipes and vapor chambers may optionally be used in combination. For example, at least one heat pipe and at least one vapor chamber may be provided extending from a heat transfer block within the internal volume of the heat sink.

[0106] In an embodiment, the heat transfer block includes a vapor chamber. Preferably, the vapor chamber of the heat transfer block is integral with the plurality of heat pipes and / or the vapor chamber extending from the heat transfer block. For example, the internal volume of the vapor chamber of the heat transfer block may be continuous with the internal volume of the plurality of heat pipes and / or the vapor chamber extending from the heat transfer block.

[0107] Returning to the general sense of the present disclosure discussed above, further optional features may be considered. For example, the cover may be arranged to seal the inner volume such that the heat sink is a cold plate.

[0108] In some implementations, the coolant inlet is in line with the plurality of heat pipes. Optionally, the coolant inlet is central to the cover.

[0109] The housing can be configured to carry coolant from the coolant inlet to the base of a plurality of heat pipes proximate to the heat transfer block. Then, the plurality of heat pipes can be arranged so that the coolant flows from the base of the plurality of heat pipes to the coolant outlet. The radiator can also include a manifold arranged so that the coolant flows from the coolant inlet to a plurality of locations at the base of the plurality of heat pipes. For example, the plurality of locations can be symmetrically arranged on the base of the plurality of heat pipes (e.g., in a plane parallel to the heat transfer block). The housing can also be configured to define the manifold.

[0110] In an embodiment, the plurality of heat pipes have different cross-sectional (in the elongated dimension) sizes and / or shapes. For example, the plurality of heat pipes may include: a first group of heat pipes, each heat pipe having a first cross-sectional area; and a second group of heat pipes, each heat pipe having a second cross-sectional area that is smaller than the first cross-sectional area, and each heat pipe is positioned between heat pipes in the first group of heat pipes. In a specific implementation, the plurality of heat pipes have a cross-sectional shape that is one of: circular; polygonal; rectangular; and hexagonal.

[0111] Optionally, the heat sink further comprises an insulating material disposed around the exterior of the housing.

[0112] In a particular embodiment, the outer surface of the electronic device has a heat distribution in use. Then, the coolant inlet of the heat sink can be aligned with the hottest part of the heat distribution. Additionally or alternatively, the center of the heat transfer block can be aligned with (or adjacent to) the hottest part of the heat distribution.

[0113] All features disclosed herein can be combined in any combination, except at least some mutually exclusive combinations of such features and / or steps. In particular, preferred features of the present invention are applicable to all aspects of the present invention and can be used in any combination. Similarly, the features described in non-essential combinations can be used individually (not in combination).

Claims

1. A radiator for cooling a heat generating device, comprising: a housing comprising: a heat transfer block for receiving heat from the heat generating device; and a side wall extending from the heat transfer block, the heat transfer block and the side wall together defining an interior volume for receiving coolant from outside the radiator; and A plurality of heat pipes and / or vapor chambers each extend from the heat transfer block within the interior volume.

2. The heat sink according to claim 1, wherein: The plurality of heat pipes and / or vapor chambers extend substantially perpendicular to the plane of the heat transfer block and / or substantially parallel to the sidewalls.

3. A heat sink according to any preceding claim, wherein: At least one of the plurality of heat pipes and / or vapor chambers has a length that is greater than a size of the heat transfer block.

4. A heat sink according to any preceding claim, wherein: The housing further comprises a cover arranged to seal the interior volume such that the heat sink is a cold plate.

5. A heat sink according to any preceding claim, further comprising: a coolant inlet for receiving coolant from outside the radiator into the interior volume; and a coolant outlet for coolant to exit the interior volume and be delivered to the exterior of the radiator.

6. The heat sink according to claim 5, wherein: The coolant outlet comprises a tube configured to receive coolant from a portion of the interior volume relatively close to the heat transfer block and to carry the received coolant relatively away from the heat transfer block in a direction perpendicular to a plane of the heat transfer block.

7. The radiator according to claim 5 or claim 6, wherein: The coolant inlet and / or the coolant outlet each include a connection port removably coupled to the housing.

8. A heat sink according to any preceding claim, wherein: The side wall is formed from a plurality of modules, each module defining a portion of the side wall, such that the modules are stacked on the heat transfer block to define the interior volume.

9. A heat sink according to any preceding claim, wherein: The plurality of heat pipes are arranged in a regular pattern, wherein the angle between the center of each heat pipe and one or more corresponding adjacent heat pipes is 60 degrees.

10. A heat sink according to any preceding claim, wherein: The plurality of heat pipes and / or vapor chambers have different cross-sectional sizes and / or shapes.

11. The heat sink according to claim 10, wherein: The plurality of heat pipes and / or vapor chambers include: a first set of heat pipes or vapor chambers, each heat pipe or vapor chamber having a first cross-sectional area; and A second set of heat pipes or vapor chambers, each heat pipe or vapor chamber having a second cross-sectional area less than the first cross-sectional area, and each heat pipe or vapor chamber is positioned between heat pipes or vapor chambers in the first set of heat pipes or vapor chambers.

12. The heat sink according to claim 10 or claim 11, wherein: The plurality of heat pipes and / or vapor chambers have a cross-sectional shape that is one of: circular; polygonal; rectangular; fin-shaped; and hexagonal.

13. A heat sink according to any preceding claim, wherein: The plurality of heat pipes and / or vapor chambers are welded or metallurgically joined into the heat transfer block.

14. A heat sink according to any preceding claim, wherein: Each of the plurality of heat pipes and / or vapor chambers is positioned within a corresponding aperture in the heat transfer block.

15. The heat sink according to any one of claims 1 to 12, wherein: The heat transfer block includes a vapor chamber integral with the plurality of heat pipes and / or vapor chambers.

16. A heat sink according to any preceding claim, further comprising: One or more baffles are disposed within the interior volume to direct coolant flow toward, away from, or through at least one heat pipe of the plurality of heat pipes and / or vapor chamber.

17. The heat sink according to claim 16, wherein: The one or more baffles include a plurality of generally planar baffles distributed in the interior volume in a direction away from the heat transfer block, with adjacent baffles covering different portions of the cross-sectional area of ​​the interior volume, thereby allowing the coolant to flow through multiple heat pipes and / or vapor chambers.

18. A heat sink according to any preceding claim, wherein One or both of the following: The housing is made of a thermally insulating material; and The heat sink also includes an insulating material disposed around an exterior of the housing.

19. A heat sink according to any preceding claim, wherein: The coolant is liquid.

20. A cooling electronic system, comprising: an electronic device that generates heat during use, the heat being dissipated from the electronic device through an external surface of the electronic device; as well as A heat sink as claimed in any preceding claim having the heat transfer block mounted on an external surface of the electronic device.

21. The cooling electronic system of claim 20, further comprising: a heat exchanger configured to receive coolant from the radiator and transfer heat from the coolant to a heat sink fluid; as well as A tube arrangement is arranged to carry coolant between the heat exchanger and the radiator.

22. The cooled electronic system of claim 21, further comprising: A pump is arranged to flow the coolant between the heat exchanger and the radiator.

23. A cooled electronic system according to any one of claims 20 to 22, wherein: The electronic device is a first electronic device, and the cooling electronic system further includes a second electronic device, wherein the second electronic device is arranged such that the coolant flowing out of the heat sink flows through the second electronic device.

24. The cooled electronic system of any one of claims 20 to 23, further comprising a chassis, the electronic device and the heat sink being located within the chassis.

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