tapering couplers and coupling methods for connecting fluid flow components are provided. In one embodiment, the tapering coupler includes a housing with a first opening and a second opening in fluid communication through the housing. The first opening is sized for a first fluid flow component to couple to the housing, and the second opening for a second fluid flow component. The first and second fluid flow components include first and second fluid-carrying channels of different diameter, with the first fluid-carrying channel having a first channel diameter that is larger than the second channel diameter of the second fluid-carrying channel. A tapering element is associated with the housing and extends into the first fluid-carrying channel. The tapering element includes a tapering fluid-carrying channel which tapers in a direction back towards the housing, for instance, from about the first channel diameter to about the second channel diameter.
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1. A method comprising:
providing a tapering coupler configured to couple a first fluid flow component and a second fluid flow component, the providing of the tapering coupler comprising:
providing a housing with a first opening and a second opening in fluid communication through the housing, the first opening being sized for the first fluid flow component to connect into the housing, and the second opening being sized for the second fluid flow component to connect into the housing, the first fluid flow component and the second fluid flow component comprising a first fluid-carrying channel and a second fluid-carrying channel, respectively, the first fluid-carrying channel having a first constant internal channel diameter and the second fluid-carrying channel having a second constant internal channel diameter, wherein the first constant internal channel diameter is larger than the second constant internal channel diameter, and wherein the housing includes an edge stop projecting radially inward, the edge stop being positioned between the first opening and the second opening in the housing with a first side closer to the first opening and a second side closer to the second opening;
providing a tapering element associated with the housing and configured to extend into and reside within the first fluid-carrying channel of the first fluid flow component when the first fluid flow component is connected into the housing, with the first fluid-carrying channel of the first fluid flow component and the first opening of the housing in fluid communication, the tapering element including a circumferential shoulder sized and positioned to reside against the second side of the edge stop within the housing, with the tapering element operatively disposed within the housing, and the tapering element comprising a tapering fluid-carrying channel which tapers down from the first constant internal channel diameter within the first fluid flow component towards the housing, and extends axially outward from the housing, the tapering element tapering from about the first constant internal channel diameter to about the second constant internal channel diameter, wherein with the first fluid flow component connected into the housing, the first fluid flow component resides, in part, within the housing, and is disposed in a radial direction, between the tapering element and a periphery of the housing, and wherein an end of the second fluid flow component within the housing contacts an end of the tapering element within the housing to maintain the circumferential shoulder of the tapering element against the second side of the edge stop within the housing; and
providing a seal disposed between an outer flange of the second flow component and the housing to facilitate sealing the second flow component to the housing.
2. The method of
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This invention was made with Government support under Contract No. H98230-13-D-0122 awarded by the United States Department of Defense. Accordingly, the U.S. Government has certain rights to this invention.
Connectors for hollow, fluid-carrying conduits or tubes have been realized in a great variety of types and shapes. These connectors include threaded fittings, push-fit connectors, flange and/or hinge-based fittings, as well as barb fittings.
In certain applications, connectors are desired for coupling conduits to other structures, such as other conduits, or to a fitting, manifold, etc. In one embodiment, it may be desirable to connect a conduit to a manifold of, for instance, a liquid-cooled assembly configured to facilitate providing cooling to at least one electronic component of an electronics rack, that is, to facilitate removal of heat generated by the electronic component(s).
Additionally, in certain applications, connectors are desired for coupling differently-sized fluid flow components. Conventional techniques for configuring connectors to couple and transition between fluid flow components with different internal flow diameters typically require additional space in order to facilitate the transition. This can be a disadvantage where space is limited, such as is the case of a fluid-cooled assembly for an electronics rack.
The shortcomings of the prior art are overcome and additional advantages are provided through, in one aspect, the provision of a method which includes: providing a tapering coupler configured to couple a first fluid flow component and a second fluid flow component. The providing the tapering coupler includes: providing a housing with a first opening and a second opening in fluid communication through the housing, the first opening being sized for the first fluid flow component to couple to the housing, and the second fluid opening being sized for the second fluid flow component to couple to the housing, the first fluid flow component and the second fluid flow component comprising a first fluid-carrying channel and a second fluid-carrying channel, respectively, the first fluid-carrying channel having a first channel diameter and the second fluid-carrying channel having a second channel diameter, wherein the first channel diameter is larger than the second channel diameter; and providing a tapering element associated with the housing and configured to extend into the first fluid-carrying channel of the first fluid flow component when the first fluid flow component is coupled to the housing, with the first fluid-carrying channel of the first fluid flow component and the first opening of the housing in fluid communication, the tapering element comprising a tapering fluid-carrying channel which tapers in a direction back towards the housing, from about the first channel diameter to about the second channel diameter.
Additional features and advantages are realized through the techniques of the present invention. Other embodiments and aspects of the invention are described in detail herein and are considered a part of the claimed invention.
One or more aspects of the present invention are particularly pointed out and distinctly claimed as examples in the claims at the conclusion of the specification. The foregoing and other objects, features, and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which:
Disclosed hereinbelow are various tapering couplers for coupling fluid flow components with different internal fluid flow diameters. For instance, the tapering couplers may facilitate coupling of a fluid conduit (or tube) to a connector fitting for a liquid manifold or liquid-manifold assembly. The tapering couplers disclosed may be provided for a variety of fluid assemblies. By way of example only, various cooling assemblies with fluid manifolds are described hereinbelow with reference to
Further, as used herein, the terms “electronics rack”, and “rack-mounted electronic equipment” are used interchangeably, and unless otherwise specified include any housing, frame, rack, compartment, blade server system, etc., having one or more heat-generating components of a computer system or electronics system, and may be, for example, a stand-alone computer processor having high, mid or low end processing capability. In one embodiment, an electronics rack may comprise one or more electronic subsystems. “Electronic subsystem” refers to any sub-housing, blade, book, drawer, node, compartment, etc., of (for example) an electronics rack having one or more heat-generating electronic components disposed therein or thereon. An electronic subsystem of an electronics rack may be movable or fixed relative to the electronics rack, with the rack-mounted electronics drawers of a multi-drawer rack unit and blades of a blade center system being two examples of subsystems of an electronics rack to be cooled. In one specific example, “electronic subsystem” refers to an electronic system which comprises multiple different types of electronic components, and may be, in one example, a server node of a multi-server rack.
“Electronic component” refers to any heat-generating electronic component of, for example, a computer system or other electronics unit requiring cooling. By way of example, an electronic component may comprise one or more integrated circuit dies and/or other electronic devices to be cooled, including one or more processor dies, memory dies and memory support dies. As a further example, an electronic component may comprise one or more bare dies or one or more packaged dies disposed on a common carrier. As used herein, “primary heat-generating component” refers to a primary heat-generating electronic component within an electronic subsystem, while “secondary heat-generating component” refers to an electronic component of the electronic subsystem generating less heat than the primary heat-generating component to be cooled. Further, unless otherwise specified herein, the terms “coolant-cooled structure” or “coolant-cooled cold plate” refer to a thermally conductive structure having one or more channels or passageways formed therein or thereon for flowing of coolant therethrough. In addition, “metallurgically bonded” refers generally herein to two components being welded, brazed or soldered together by any means.
As used herein, a “liquid-to-liquid heat exchanger” may comprise, for example, two or more coolant flow paths, formed of thermally conductive tubing (such as copper or other tubing) in thermal or mechanical contact with each other. Size, configuration and construction of the liquid-to-liquid heat exchanger can vary without departing from the scope of the invention disclosed herein. Further, “data center” refers to a computer installation containing one or more electronics racks to be cooled. As a specific example, a data center may include one or more rows of rack-mounted computing units, such as server units.
One example of a coolant (for example, the facility or system coolants discussed below) is water. However, the concepts disclosed herein are readily adapted to use with other types of coolant. For example, one or more of the coolants may comprise a glycol mixture, a brine, a fluorocarbon liquid, a liquid metal, or other similar coolant, or refrigerant, while still maintaining the advantages and unique features of the present invention.
Reference is made below to the drawings, which are not drawn to scale to facilitate understanding of the invention, wherein the same reference numbers used throughout different figures designate the same or similar components.
Due to the ever-increasing airflow requirements through electronics racks, and the limits of air distribution within the typical data center installation, coolant-assisted cooling is being combined with the conventional air-cooling.
In addition to CCUs 230, the cooling system includes a system water supply manifold 231, a system water return manifold 232, and manifold-to-node fluid connect hoses 233 coupling system water supply manifold 231 to electronic subsystems 210, and node-to-manifold fluid connect hoses 234 coupling the individual electronic subsystems 210 to system water return manifold 232. Each CCU 230 is in fluid communication with system water supply manifold 231 via a respective system water supply hose 235, and each CCU 230 is in fluid communication with system water return manifold 232 via a respective system water return hose 236.
As illustrated, a portion of the heat load of the electronic subsystems is transferred from the system water to cooler facility water supplied by facility water supply line 240 and facility water return line 241 disposed, in the illustrated embodiment, in the space between a raised floor 201 and a base floor 202.
The illustrated coolant-based cooling system further includes multiple coolant-carrying tubes connected to and in fluid communication with coolant-cooled cold plates 520. The coolant-carrying tubes comprise sets of coolant-carrying tubes, with each set including (for example) a coolant supply tube 540, a bridge tube 541 and a coolant return tube 542. In this example, each set of tubes provides coolant to a series-connected pair of cold plates 520 (coupled to a pair of processor modules). Coolant flows into a first cold plate of each pair via the coolant supply tube 540 and from the first cold plate to a second cold plate of the pair via bridge tube or line 541, which may or may not be thermally conductive. From the second cold plate of the pair, coolant is returned through the respective coolant return tube 542.
As noted, various coolants significantly outperform air in the task of removing heat from heat-generating electronic components of an electronic system, and thereby more effectively maintain the components at a desirable temperature for enhanced reliability and peak performance. As coolant-based cooling systems are designed and deployed, it is advantageous to architect systems which maximize reliability and minimize the potential for leaks while meeting all other mechanical, electrical and chemical requirements of a given electronic system implementation. These more robust cooling systems have unique problems in their assembly and implementation. For example, one assembly solution is to utilize multiple fittings within the electronic system, and use flexible plastic or rubber tubing to connect headers, cold plates, pumps and other components. In another approach, a robust coolant-assisted cooling system may be provided, specially preconfigured and prefabricated as a monolithic structure for positioning within a particular electronics drawer.
More particularly,
In addition to coolant-cooled cold plates 620, coolant-based cooling system 615 includes multiple coolant-carrying tubes, including coolant supply tubes 640 and coolant return tubes 642 in fluid communication with respective coolant-cooled cold plates 620. The coolant-carrying tubes 640, 642 are also connected to a header (or manifold) subassembly 650 which facilitates distribution of coolant to the coolant supply tubes and return of coolant from the coolant return tubes 642. In this embodiment, the air-cooled heat sinks 634 coupled to memory support modules 632 closer to front 631 of electronics drawer 613 are shorter in height than the air-cooled heat sinks 634′ coupled to memory support modules 632 near back 633 of electronics drawer 613. This size difference is to accommodate the coolant-carrying tubes 640, 642 since, in this embodiment, the header subassembly 650 is at the front 631 of the electronics drawer and the multiple liquid-cooled cold plates 620 are in the middle of the drawer.
Coolant-based cooling system 615 comprises a pre-configured monolithic structure which includes multiple (pre-assembled) coolant-cooled cold plates 620 configured and disposed in spaced relation to engage respective heat-generating electronic components. Each coolant-cooled cold plate 620 includes, in this embodiment, a coolant inlet and a coolant outlet, as well as an attachment subassembly (i.e., a cold plate/load arm assembly). Each attachment subassembly is employed to couple its respective coolant-cooled cold plate 620 to the associated electronic component to form the cold plate and electronic component assemblies. Alignment openings (i.e., thru-holes) are provided on the sides of the cold plate to receive alignment pins or positioning dowels during the assembly process. Additionally, connectors (or guide pins) are included within attachment the subassembly, which facilitate use of the attachment assembly.
As shown in
The above-described cooling approach of
The efficient extraction of heat from electronic modules, nodes and/or racks, becomes more important as heat generated within the modules, nodes or racks increases. Lacking an efficient heat transfer mechanism, the speed, reliability and power capabilities of the electronic circuit modules, nodes and rack, will be limited. As the density of circuitry within a given space is increased, the need for improved heat extraction becomes more important. As explained above in connection with
Disclosed herein are apparatuses and methods, for space-constrained systems, to reduce overall cooling system flow impedance for improved system flow, and thus, improved thermal performance, resulting in a more efficient heat transfer for cooling an electronic structure, such as an electronic module, node or rack. As one specific example, pressure drop where a coolant flow conduit connects to a coolant manifold may be about 20% of the total pressure drop through a coolant-carrying assembly, such as the coolant pressure drop through a cooled electronic subsystem or node described above.
More particularly, the apparatuses and methods of fabrication disclosed herein include tapering couplers that facilitate reducing or minimizing loss of energy in a fluid when transitioning from one channel flow diameter to another channel flow diameter, where the channel flow diameters are differently sized. For instance, pressure drop may occur where a fluid flow transitions from a first fluid flow component with a small cross-sectional flow area to a second fluid flow component with a larger cross-sectional flow area. The same issue arises when fluid flow transitions from a larger cross-sectional flow area to a smaller cross-sectional flow area. Note that as used herein, “fluid flow component” or “flow component” refers generally to any conduit, fitting, manifold, housing, structure, etc., having a fluid-carrying channel, with the conduit-to-fitting couplers described below with reference to
By way of specific example, the first fluid flow component 720 may be a metal conduit or tube, and coupler 710 may include a metal housing, with the metal conduit being secured to the coupler by welding after inserting the end of the metal conduit within opening 711 of coupler 710. Fluid flow component 730 may, in one example, be threadably secured to coupler 710 by providing appropriately sized and configured threads within opening 712 of coupler 710, and on the end of component 730 engaging the coupler.
In the embodiments of
Where ΔP is the pressure loss (drop), ρ is the fluid density, and V is the mean fluid velocity entering the transition.
If the expansion or contraction is gradual, as in a gradual conical expansion or contraction (i.e., a diffuser), the pressure loss can be significantly reduced. Relative to a sudden expansion or contraction (θ=90°), a diffuser with a gradual expansion or contraction defined by an angle θ=5°, the pressure loss can be reduced by 75% in the expansion case, and by 86% in the contraction case, as shown in
Generally stated, disclosed herein are apparatuses and methods which include or provide a tapering coupler that comprises a housing and a tapering element associated with the housing. The housing includes a first opening and a second opening in fluid communication through the housing, with the first opening being sized for a first fluid flow component to couple to the housing, and the second opening being sized for a second fluid flow component to couple to the housing. The first fluid flow component and second fluid flow component include a first fluid-carrying channel and a second fluid-carrying channel, respectively, with the first fluid-carrying channel having a first channel diameter and the second fluid-carrying channel having a second channel diameter. The first channel diameter is larger than the second channel diameter. Note that as used herein, the “channel diameter”, “internal flow diameter”, “flow diameter”, or “cross-sectional flow area” are used interchangeably, and refer to the characteristic diameter of a fluid flow channel through a fluid flow component. The tapering element associated with the housing is configured to extend into the first fluid-carrying channel of the first fluid flow component when the first fluid flow component is coupled to the housing, with the first fluid-carrying channel of the first fluid flow component and the first opening of the housing in fluid communication. The tapering element includes a tapering fluid-carrying channel which tapers in a direction towards the housing from about the first channel diameter to about the second channel diameter. In one implementation, the tapering element extends outwards from the housing, and the tapering fluid-carrying channel of the tapering element tapers uniformly from about the first channel diameter to the second channel diameter at a taper angle θ. In certain implementations, taper angle θ is within a 1-10° taper range, and more particularly, in a range of 3-7°. For instance, taper angle θ may be about a 5° taper angle.
Note that approximating language, as used herein throughout the specification and claims, is applied to modify any quantitative representation that could permissibly vary without resulting in change in the basic function to which it is related. A value modified by a term such as “about”, is not limited to a precise value specified. For instance, tapering of the tapering fluid-carrying channel progresses from slightly smaller than the first channel diameter is due to the thickness of the material at the end of the tapering element farthest from the housing. For instance, the tapering may proceed from the first channel diameter, less a few millimeters' thickness of the tapering element, down to the second channel diameter.
In certain implementations, the tapering element is formed integral with the housing to be a part of the housing, and the first opening in the housing is disposed in the tapering element. In one embodiment, the housing further includes a recess surrounding the tapering insert element. The recess is configured to receive an end of the first fluid flow component, to facilitate coupling of the first fluid flow component to the housing, with the tapering element extending into the first fluid-carrying channel of the first fluid flow component. By way of example, the tapering element may extend from a first side of the housing, and the second opening may be disposed in a second side of the housing, where the first and second sides of the housing are opposite sides of the housing.
In other implementations, the tapering element may be a tapering insert element distinct from the housing, but secured to the housing. For instance, the tapering insert element may be separately fabricated (for instance, of a plastic or metal) and inserted into the housing so as to be secured within the housing. By way of example, the tapering insert element may be inserted into the housing through the second opening so as to project out through the first opening in the housing. By way of example, a shoulder may be provided within the housing, sized and configured to be engaged by a circumferential ring or shoulder about the tapering insert element with insertion of the tapering insert element into the housing, through the second opening. In such a case, the tapering insert element may be secured within the housing by threadably inserting an end of the second fluid flow component into the second opening of the housing, thereby securing the tapering insert element within the housing.
In certain embodiments, the tapering element is configured such that the tapering fluid-carrying channel of the tapering element resides within, at least in part, the first fluid flow component when the first fluid flow component and the housing are coupled with the first fluid-carrying channel of the first fluid flow component and the first opening of the housing in fluid communication. For instance, at least a portion of the tapering fluid-carrying channel may reside within the first fluid flow component. In certain implementations, a portion of the tapering fluid-carrying channel may reside within the housing, depending upon the length required in order to achieve the gradual transition or taper desired. Fluid-carrying assemblies and methods of fabrication are also described below.
In one implementation, the connector apparatus may be employed for a cooling assembly, such as described above in connection with
As shown in
In one embodiment, a circumferential recess 913 may be provided in housing 910 about a tapering element 915 to accommodate an end of first fluid flow component 720, for instance, to facilitate coupling and securing of the fluid flow component to housing 910, for instance, by welding or brazing. In one implementation, second opening 912 may include threads (not shown) sized and configured to facilitate threaded insertion of second fluid flow component 730 therein. One or more O-rings or gaskets 914 may be provided in association with second fluid flow component 730, and/or first fluid flow component 720 and/or housing 910, to facilitate fluid-tight coupling of the components and housing. Use of O-rings or gaskets may depend, in part, on the type of component the first and second fluid flow components 720, 730 represent, and how they are secured to housing 910. As noted, and by way of example only, first fluid flow component 720 is depicted as a fluid conduit, and second fluid flow component 730 is depicted as a fitting, such as a quick connect fitting, to facilitate coupling of the fluid conduit to, for instance, a part of a liquid manifold of a fluid-carrying assembly, such as illustrated in
As illustrated in
Connector apparatus 1000 includes first fluid flow component 720 and second fluid flow component 730, which, as noted above in connection with
As illustrated in
As in the embodiment of
As illustrated, tapering insert element 1015 includes a tapering fluid-carrying channel 1017, which tapers in a direction back towards the housing, from about the first channel diameter d1 of first fluid-carrying channel 722 to about the second channel diameter d2 of second fluid-carrying channel 732. As noted above, the taper angle may be uniform through the tapering insert element, and be, for instance, in a range of 1-10°, or more particularly, in a range of 3-7°. Depending on the implementation, and the difference between the first and second channel diameters, a majority of the tapering insert element 1015 may reside within the first fluid flow component 720, having the larger channel diameter, when the connector apparatus is operatively employed as depicted in
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprise” (and any form of comprise, such as “comprises” and “comprising”), “have” (and any form of have, such as “has” and “having”), “include” (and any form of include, such as “includes” and “including”), and “contain” (and any form of contain, such as “contains” and “containing”) are open-ended linking verbs. As a result, a method or device that “comprises,” “has,” “includes,” or “contains” one or more steps or elements possesses those one or more steps or elements, but is not limited to possessing only those one or more steps or elements. Likewise, a step of a method or an element of a device that “comprises,” “has,” “includes,” or “contains” one or more features possesses those one or more features, but is not limited to possessing only those one or more features. Furthermore, a device or structure that is configured in a certain way is configured in at least that way, but may also be configured in ways that are not listed.
The corresponding structures, materials, acts, and equivalents of all means or step plus function elements in the claims below, if any, are intended to include any structure, material, or act for performing the function in combination with other claimed elements as specifically claimed. The description of the present invention has been presented for purposes of illustration and description, but is not intended to be exhaustive or limited to the invention in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the invention. The embodiment was chosen and described in order to best explain the principles of one or more aspects of the invention and the practical application, and to enable others of ordinary skill in the art to understand one or more aspects of the invention for various embodiments with various modifications as are suited to the particular use contemplated.
Ellsworth, Jr., Michael J., Arvelo, Amilcar R., McKeever, Eric J.
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Sep 09 2014 | MCKEEVER, ERIC J | International Business Machines Corporation | ASSIGNMENT OF ASSIGNORS INTEREST SEE DOCUMENT FOR DETAILS | 036310 | /0595 | |
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