Jet cooling with internally structured parts

Abstract

Methods and systems for the manufacture of metal parts for jet impingement. Some embodiments include a metal part comprising a housing region and at least one internal plumbing feature encapsulated by the housing region and configured to cool a heat source via a fluid. In some embodiments, the internal plumbing feature comprises at least one of an internal channel, a delivery manifold, a drain manifold, a void space configured to flow the fluid, a jet orifice configured to jet the fluid, or a target object to receive the jetted fluid.

Description

ALY-020PCJET COOLING WITH INTERNALLY STRUCTURED PARTSCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The present application claims the benefit of and priority to United States Provisional Application No. 63 / 717,813, filed on November 7, 2024, the entire disclosure of which is hereby incorporated by reference as if set forth in its entirety herein.TECHNICAL FIELD

[0002] Embodiments described herein generally relate to methods and apparatus for fabricating metal object parts, and more specifically to the manufacture of metal parts for jet cooling.BACKGROUND

[0003] High electron mobility transistors (HEMTs) and other high-power electronic devices can generate significant amounts of heat in compact geometries. The small form factors and large power densities of these devices present substantial challenges for thermal management, as localized hot spots may lead to performance degradation, reduced device lifetime, or system failure if not adequately cooled.

[0004] Traditional cooling strategies often rely on thermal interface materials, such as electrical or thermal interface gels, to mate a device with a cooling part, such as a heat sink. While the gels can improve contact between different surfaces, their thermal conductivity remains at least an order of magnitude lower than that of direct metal -to-metal interfaces. As a result, significant thermal resistance can persist at the gel interface, limiting overall heat transfer efficiency.

[0005] In recent years, microfluidic jet cooling has emerged as a promising solution for removing heat from high-power electronic devices. Jet cooling can involve impinging fluid jets onto a surface to cool a device, such as a surface of the device or a thermally conductive interface plate. In this manner, jet cooling parts can achieve high heat transfer performance and cooling uniformity across the device.

[0006] Conventional manufacturing techniques, however, such as machining, drilling or etching, make it difficult to form jet cooling parts with both high flow volume and sub-millimeter channel dimensions needed for optimal jet impingement. Precise control over internal geometries avoids dry-out, maintains a high level of heat transfer performance, and maximizes the packing density of internals features such as channels. Furthermore, conventional techniques often require gaskets, seals, adhesives, or thread-sealing tapes to bond multiple parts together. These additionalALY-020PC interfaces can reduce reliability concerns and impose mechanical and thermal mismatches that further degrade heat transfer performance.

[0007] Additive manufacturing techniques, such as LOM, may introduce new limitations and opportunities for part configuration. In LOM, the force transmission limitation for bonding a plurality of sheets and the self-supporting stencil limitation for handling each individual sheet may introduce design restrictions to create a network of fluidically connected jetting channels.

[0008] Accordingly, a need exists for improved methods of manufacturing metal parts for jet cooling.SUMMARY

[0009] This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description section. This summary is not intended to identify or exclude key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

[0010] In one aspect, the techniques described herein relate to a metal part including: a housing region; and at least one internal plumbing feature encapsulated by the housing region and configured to cool a heat source via a fluid, wherein the internal plumbing feature includes at least one of an internal channel, a delivery manifold, a drain manifold, a void space configured to flow the fluid, a jet orifice configured to jet the fluid, or a target object to receive the jetted fluid.

[0011] In some embodiments, the metal part includes a single-build part formed without welding separate components together.

[0012] In some embodiments, the jet orifice is configured to jet the fluid on at least one of the heat source or a thermally conductive window via a jetting chamber.

[0013] In some embodiments, the window is placed along an external surface of the part and is in thermal contact with the heat source.

[0014] In some embodiments, the internal channel fluidically connects the jetting chamber to the manifold for draining the fluid after jetting.

[0015] In some embodiments, the internal channel originates at the manifold and terminates at the jet orifice.

[0016] In some embodiments, the jet orifice has the same diameter as the internal channel.

[0017] In some embodiments, the housing region includes at least one port for enabling the fluid to flow into or out of the metal part.ALY-020PC

[0018] In some embodiments, the at least one port includes an inlet port and an outlet port, wherein the inlet port is configured to mate with a fluid source.

[0019] In some embodiments, the metal part further includes a plurality of jet impingement structures including the at least one internal plumbing feature, and wherein at least one of the jet impingement structures is mechanically separated from at least one other jet impingement structure.

[0020] In some embodiments, the at least one internal plumbing feature includes an encapsulated orifice plate terminating at the jet orifice.

[0021] In some embodiments, the metal part is manufactured via an additive manufacturing process.

[0022] In another aspect, the techniques described herein relate to a method for forming a metal part via an additive manufacturing process, the method including: patterning a plurality of metal sheets; stacking the patterned metal sheets; and bonding the stacked metal sheets to form the metal part, the metal part including: a housing region; and at least one internal plumbing feature encapsulated by the housing region and configured to cool a heat source via a fluid, wherein the internal plumbing feature includes at least one of an internal channel, a delivery manifold, a drain manifold, a void space configured to flow the fluid, a jet orifice configured to jet the fluid, or a target object to receive the jetted fluid.

[0023] In some embodiments, the jet orifice is configured to jet the fluid on at least one of the heat source or a thermally conductive window via a jetting chamber.

[0024] In some embodiments, the internal channel originates at the manifold and terminates at the jet orifice.

[0025] In some embodiments, the jet orifice has the same diameter as the internal channel.

[0026] In some embodiments, the housing region includes at least one port for enabling the fluid to flow into or out of the metal part.

[0027] In some embodiments, the housing region includes at least one mounting component for interfacing with a cooling system.

[0028] In some embodiments, the heat source is aligned orthogonally with respect to the plurality of metal sheets during operation.

[0029] In yet another aspect, the techniques described herein relate to a system for forming a metal part via an additive manufacturing process, the system including: an additive object manufacturing device configured to: pattern a plurality of metal sheets; and stack the patternedALY-020PC metal sheets; and a pressor configured to bond the stacked metal sheets by applying a mechanical force for forming the metal part, the metal part including: a housing region; and at least one internal plumbing feature encapsulated by the housing region and configured to cool a heat source via a fluid, wherein the internal plumbing feature includes at least one of an internal channel, a delivery manifold, a drain manifold, a void space configured to flow the fluid, a jet orifice configured to jet the fluid, or a target object to receive the jetted fluid.BRIEF DESCRIPTION OF DRAWINGS

[0030] Non-limiting and non-exhaustive embodiments of this disclosure are described with reference to the following figures, wherein like reference numerals refer to like parts throughout the various views unless otherwise specified:

[0031] Figure 1 depicts a cross-section of a metal part;

[0032] Figure 2 depicts a cross-section of another metal part;

[0033] Figure 3 depicts a cross-section of yet another metal part;

[0034] Figure 4 depicts a cross-section of yet another metal part;

[0035] Figure 5 depicts a flow path of a self-contained j et impingement structure; and

[0036] Figure 6 depicts a flow path of another self-contained jet impingement chamber.DETAILED DESCRIPTION

[0037] Various embodiments are described more fully below with reference to the accompanying drawings, which form a part hereof, and which show specific exemplary embodiments. However, the concepts of the present disclosure may be implemented in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided as part of a thorough and complete disclosure, to fully convey the scope of the concepts, techniques and implementations of the present disclosure to those skilled in the art. Embodiments may be practiced as methods, systems or devices. The following detailed description is, therefore, not to be taken in a limiting sense.

[0038] Reference in the specification to “one embodiment” or to “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiments is included in at least one example implementation or technique in accordance with the present disclosure. The appearances of the phrase “in one embodiment” in various places in the specification are not necessarily all referring to the same embodiment.ALY-020PC

[0039] In addition, the language used in the specification has been principally selected for readability and instructional purposes and may not have been selected to delineate or circumscribe the disclosed subject matter. Accordingly, the present disclosure is intended to be illustrative, and not limiting, of the scope of the concepts discussed herein.Definitions

[0040] Unless otherwise specified, the following terms as used herein shall have the meanings as provided below:

[0041] The term “laminated object manufacturing” (LOM) refers to a method of manufacturing a part, containing additive and subtractive steps, beginning with contiguous sheets of material and processing sheets sequentially to form a part.

[0042] The term “bonding” refers to the process through which the contiguous sheets of material are formed into a part. The workpiece is subjected to heat and / or applied force which form covalent and / or metallic bonds between the sheets of material, forming an object.

[0043] The term “part” refers to a heat exchanger or other object manufactured through LOM.

[0044] The term “encapsulate” refers to a material that is enclosed by the part that may have different bulk properties than the part material. In some embodiments, the encapsulate may be fully enclosed within the part or enclosed by the part and an external object such as a heat source. In some embodiments, the encapsulate may serve as an orifice plate or a window.

[0045] The term “workpiece” refers to a stack of metal sheets to be bonded into at least one part.

[0046] The term “metal sheet” refers to a metal sheet or foil that is stacked in the workpiece. Each metal sheet may be patterned to contain part regions and support structure regions. In some embodiments, the metal sheet may comprise at least one of aluminum, copper, magnesium, titanium, aluminum alloy, magnesium alloy, and / or titanium alloy.

[0047] The term “sheet” refers generally to a metallic layer between 25 pm to 10 cm in thickness.

[0048] The term “void” refers to a volume cut out of a metal sheet in the support or part region which is fully enclosed and not fluidically connected to any other internal channel or port within the workpiece.

[0049] The term “internal chamber” refers to a fluidically connected void space within a part. An internal chamber may serve as the envelope of a heat pipe or otherwise be charged with a fluid and sealed to serve as a cooling part such as a jet cooling part.ALY-020PC

[0050] The term “flow path” refers to a traceable path of void space through internal channels in the part from at least one external port to at least a second external port.

[0051] The term “channel” refers to at least a portion of the void space in the flow path.

[0052] The term “fluid” refers to any suitable refrigerant capable of flowing through a part. Suitable refrigerants may include water, ammonia, acetone, methanol, ethanol, and / or other specialized refrigerants.

[0053] The term “jet impingement” refers to a process in which a fluid jet is directed toward a solid surface.

[0054] The term “internal plumbing feature” refers to any feature of a part that facilitates fluid flow at the part.

[0055] The term “coefficient of thermal expansion” (CTE) refers to a material property that measures the degree to which a material changes in size in response to a change in temperature. The change in size may be represented as a change in a single dimension (e.g., length) or in volume.Embodiments

[0056] Embodiments of this invention include configurations of metal parts configured for jet cooling. In some embodiments, a metal part may include internal plumbing features for jet cooling, such as micro-channels and jet orifices. In some embodiments, the metal part may be a singlebuild part where the regions of the metal part are manufactured in a single build. In some embodiments, the metal part may be manufactured additively, such as via laminated object manufacturing, or using traditional manufacturing and finishing techniques. The embodiments described herein may allow the manufacture of smooth and efficient jet cooling structures while reducing or eliminating interference between jets that may otherwise erode thermal performance on larger parts.

[0057] Non-limiting examples of these configurations are further discussed below.LOM Manufacturing

[0058] In embodiments of this invention, a metal part may be assembled via at least one additive or subtractive manufacturing technique. The metal part may be any suitable part configured to transfer heat away from a heat source, such as cold plates, heat sinks, and / or jet cooling parts. Suitable techniques may include LOM, diffusion bonding, brazing, friction stir welding, transient liquid phase bonding, electroplating, electrodeposition, etching, computer numerical control (CNC) micromachining, laser cutting, stereolithography (SLA), and / or powder bed fusion.ALY-020PC

[0059] In LOM, a workpiece consisting of a plurality of metal sheets may be assembled and bonded. The workpiece may be assembled in a laminated fashion with the metal sheets. In this manner, the workpiece may be a layered workpiece assembled by depositing the metal sheets. The metal sheets may be patterned such that the pattern of the metal sheets partitions the workpiece into at least one support region and at least one part region. The metal sheets may be bonded in a heated press, a more complicated bonding machine comprising a heated press and a vacuum chamber, and / or a bonding machine of any configuration to form a metal part such as but not limited to a jet cooling part. The metal sheets may be bonded by applying a mechanical force along at least one axial direction of the metal sheets.

[0060] In some embodiments, the part regions may be assembled within a build volume of the workpiece. The build volume may be defined as the geometric volume enclosed by the external faces of the stack of patterned metal sheets.

[0061] In some embodiments, the part regions may be configured to sit at some arbitrary orientation or angle with respect to at least one of the external faces of the build volume. This angle may be selected to reduce or minimize the length of channels or other internal geometric features within a single patterned sheet.

[0062] In some embodiments, each metal sheet may have a unique pattern which comprises a cross-sectional slice of the metal part. The pattern on each metal sheet (e.g., a pattern of void spaces) may be configured to transmit force through the metal sheets. The pattern on each metal sheet may be configured to be self-supporting such that the metal sheet may be patterned and subsequently handled without damage. Exemplary sources of damage to a patterned metal sheet may include, but are not limited to, manipulation by a robotic arm, conveyance along a belt, and / or interactions with high pressure gas from metal laser cutting. Thus, metal sheets may be stenciled in strong, rigid, contiguous structures. Isolated features on a single metal sheet may be held in place with bridges so that the metal sheet is contiguous.

[0063] In some embodiments, the metal sheets may be patterned so that material is removed from at least one part region of each metal sheet. This may create a pattern of void spaces within the workpiece. The void spaces may be formed via any appropriate cutting technique, such as drag knife cutting, laser cutting, and / or etching. The void spaces may be formed from regular, geometric patterns and / or random distributions within the workpiece.

[0064] In some embodiments, the metal part may at least partially comprise an encapsulate. The encapsulate may replace a sheet or multiple sheets of the metal part or may replace a fraction of a sheet or multiple sheets of the metal part. The encapsulate may be mechanically locked inALY-020PC place or bonded to the metal part. The encapsulate may be configured to be fully enclosed within the part or be configured to comprise an external surface of the part and be enclosed by the part and an external object such as a heat source.

[0065] In some embodiments, the encapsulate may be clad in a material that may be bonded to the bulk of the part. The cladding may be deposited via at least one of electroplating, physical vapor deposition (PVD), chemical vapor deposition (CVD), or other plating techniques. An optional diffusion bonding step may be subsequently added to the above cladding deposition step to bond the cladding to the encapsulate.

[0066] In some embodiments, the thickness of the cladding layer on the encapsulate is on the same order of magnitude as the tolerances required by the LOM process. In some embodiments, the thickness of the cladding layer may be less than the thickness of a single sheet in the laminated object manufacturing process.Metal Part

[0067] In embodiments of this invention, a metal part may be configured to direct fluid as a fluid jet onto a target object, such as a separate object, a thermally conductive window which may be in contact with an object, a thermally conductive window which may be incorporated into the metal part, and / or the metal part itself. The metal part may direct the fluid to transfer heat away from the target object using jet impingement. The target object of the jet impingement may be a heat source, such as high electron mobility transistors (HEMTs), laser diodes, power amplifiers, microprocessors, and / or light-emitting diodes (LEDs).

[0068] In some embodiments, the metal part may be formed as a single-build part using a single manufacturing process, such as LOM. The single-build part may be formed without the need for welding and / or soldering components to form any internal and / or surface features.

[0069] In some embodiments, the metal part may be manufactured from a thermally conductive metal such as copper, aluminum, or magnesium, and / or from an alloy thereof. A thermally conductive metal part may be configured to use the external surface of the part as a window to a jetting chamber. The metal part may optionally incorporate surface treatments, coatings, and / or structural reinforcements to improve corrosion resistance, electrical insulation, and / or mechanical durability under repeated heat transfer cycles.

[0070] In some embodiments, the metal part may be manufactured from a less thermally conductive metal such as titanium or stainless steel, any other suitable metals, and / or alloys thereof. Less thermally conductive metal parts may include an encapsulate and / or a window of a more thermally conductive material to transfer heat from an external heat source. The encapsulateALY-020PC and / or window may have a coefficient of thermal expansion (CTE) similar to that of the heat source. In some embodiments, less thermally conductive metal parts may incorporate surface treatments, coatings, and / or structural reinforcements to improve corrosion resistance, electrical insulation, electrical conductivity, and / or mechanical durability under repeated heat transfer cycles.

[0071] In some embodiments, the metal part may include any number of internal plumbing features forjet impingement, such as internal channels, manifolds, jet orifices, and / or other internal void spaces. The internal plumbing features may facilitate jet impingement at the metal part (e.g., by facilitating fluid flow within the part). The internal plumbing features may facilitate smooth distribution and return of the jetted fluid (e.g., to minimize cross-flow disruption) by separating flow paths in-plane while connecting the flow paths orthogonally to the plane of the metal sheets.

[0072] In some embodiments, the metal part may at least partially comprise an encapsulate. The encapsulate may have a thermal conductivity greater than that of the part, thereby enhancing heat transfer from the heat source. The encapsulate may comprise a material that is more compliant to strain than the part. In some embodiments, the encapsulate may have a CTE similar to that of the heat source, thereby reducing strain from thermal expansion.

[0073] In some embodiments, the encapsulate may include at least one of a compliant form of graphite, diamond, a tungsten-copper alloy, a molybdenum-copper alloy, and / or molybdenum disulfide alloy, an aluminum-nitride alloy, a boron-nitride compound, and / or a silicon-carbide compound. In some embodiments, the encapsulate may include at least one of an oxide ceramic, non-oxide ceramic, and / or a silicate ceramic.

[0074] In some embodiments, the metal part may include a housing region. The housing region may encapsulate and / or protect the internal plumbing features. The housing region may serve as a mechanical structure for supporting the metal part and / or as an enclosure for directing fluid flow through the internal plumbing features.

[0075] In some embodiments, the housing region may include at least one port configured to interface with external plumbing. The port may allow the introduction and / or removal of fluid at the part. For example, an inlet port may comprise a fitting configured to mate with an external fluid source, such as a pump or pressurized reservoir. An outlet port may include at least one orifice for discharging fluid.

[0076] In some embodiments, the housing region may include multiple inlet ports and / or outlet ports, such as an array of ports arranged in regular or irregular patterns. In some embodiments,ALY-020PC the ports may be placed on different faces of the housing region. In some embodiments, the ports may be placed on a single face of the housing region.

[0077] In some embodiments, the internal plumbing features may include a delivery manifold configured to distribute fluid to downstream features such as channels and / or jet orifices. The delivery manifold may serve as an intermediate chamber or network that ensures that the downstream features receive fluid. In some embodiments, the internal plumbing features may include a drain manifold may also be configured to receive fluid from upstream features such as a jetting chamber, array of channels, and / or jet orifices.

[0078] In some embodiments, the manifold may include an internal chamber. In some embodiments, the manifold may include internal supports or porous-like architectures. In some embodiments, the manifold may include a lattice structure. The lattice structure may have any suitable periodic or aperiodic geometry. Examples include, but are not limited to, gyroidal structures, Schwarz diamond surfaces, and other triply periodic minimal surfaces (TPMS).

[0079] In some embodiments, the manifold may include a hierarchical arrangement of lattice structures. For example, coarser lattices may provide most of the fluid distribution while finer lattices may condition and direct flow toward specific features. In some embodiments, the manifold may be graded, with varying porosity or cell size across its volume.

[0080] In some embodiments, the internal plumbing features may include a network of narrow channels configured to extend through at least a portion of the metal part. The channels may fluidically connect internal plumbing features such as manifolds, chambers, and / or inlet ports to jet orifices and / or outlet ports. For example, a channel may originate at a manifold that distributes incoming fluid and terminate at a jet orifice. In some examples, multiple channels may branch from a common manifold and be arranged in parallel or intersecting configurations to provide uniform distribution across an array of jet orifices or outlet ports.

[0081] In some embodiments, a channel may have a dimension characteristic (e.g., a hydraulic diameter, a length, a circumference, etc.) of 300 microns or less. In some embodiments, the dimension characteristic may be between 50 microns and 300 microns. Such microscale dimensions may enable the generation of high-velocity fluid jets at moderate input pressures, improving heat transfer while minimizing total fluid consumption.

[0082] The channels may have any suitable cross-sectional shape. For example, the channels may be circular, elliptical, square, and / or rectangular in cross-section, or may have tapered geometries. The channel walls may optionally be textured, coated, and / or chemically treated to reduce fouling, enhance nucleation during two-phase operation, and / or improve wettability.ALY-020PC

[0083] In some embodiments, the channels may be straight and uniform in length. In some embodiments, the channels may be curved, angled, and / or branched to accommodate complex part geometries or to direct fluid toward specific heat-generating regions.

[0084] In some embodiments, the channels may be configured for a single-phase and / or two- phase cooling process. For example, the channels may be configured to carry a liquid or gas for single-phase cooling processes or may support nucleate boiling and vapor transport for two-phase cooling processes.

[0085] In some embodiments, multiple channels that are fluidly connected may form a flow path. At least one flow path may be traced through the metal part. The flow path may be a complete flow path connected to at least two externally accessible ports on the metal part, such as an inlet port and an outlet port.

[0086] In some embodiments, the flow path may consist of multiple channels in parallel. Multiple channels may merge into one or more flow paths in at least a portion of the metal part. A single channel may split into multiple channels in at least a portion of the metal part, creating branching flow paths. Flow paths may be merged or split so that one inlet or outlet port may service multiple complementary ports.

[0087] In some embodiments, multiple flow paths may be configured through the metal part in a cross-flow pattern, with, for example, horizontal flow paths and vertical flow paths with ports on multiple faces of the metal part. Upstream and downstream segments of a flow path may be interleaved and / or alternated to optimize thermal performance while addressing the force transfer and self-supporting sheet constraints of LOM.

[0088] In some embodiments, a channel may terminate at an orifice through which fluid is discharged as a fluid jet. The orifice may be configured to control the flow characteristics of the fluid jet as it impinges on a target object.

[0089] In some embodiments, an encapsulate may be configured in the metal part to serve as an orifice plate. The orifice plate may include at least one channel configured to terminate in at least one orifice. Any suitable machining, cutting, and / or manufacturing technique may be performed on the encapsulate to shape the channels and achieve a desired cross-section.

[0090] In some embodiments, the orifice may have substantially the same diameter (and / or any other dimension characteristic) as the upstream channel, thereby reducing flow disturbances and simplifying manufacturing. In some embodiments, the orifice may have a different diameter and / or dimension characteristic than that of the channel. For example, the metal part may include a tapered section between the channel and the orifice to provide nozzle or flow restriction. TheALY-020PC tapered section may have a dimension characteristic on the order of microns to hundreds of microns.

[0091] In some embodiments, the orifice may include convergent internal geometry to compress and accelerate the fluid into a narrow jet stream. In some embodiments, the orifice may adopt a convergent-divergent geometry (e.g., a de Laval nozzle), allowing the jet to expand.

[0092] In some embodiments, the orifice may be configured with a predetermined pressure drop to spray the fluid jet at a given pressure. The pressure drop may be optimized to generate strong jets and / or increase heat transfer between the fluid and the target object.

[0093] In some embodiments, multiple orifices may be arranged in arrays or patterns to cover specific thermal footprints. The orifices may be arranged to balance local jet interactions with overall heat transfer performance. For example, the orifices may be arranged to deliver uniform coverage across the entire target region. The orientation of the orifices may be configured to spray fluid at different angles, such as perpendicular jets and / or oblique jets.

[0094] In some embodiments, the orifices may include valves and / or other features to dynamically adjust jet impingement, such as by selectively activating certain orifices. For example, a first array of orifices may be configured as the primary orifices for addressing thermal loads, while a second array may be activated (e.g., by opening their valves) during periods of high thermal loads.

[0095] In some embodiments, the downstream edge of the orifice may be finished or shaped to affect the fluid jet. For example, the downstream edge may control the degree of jet coherence, the onset of turbulence, and / or the overall pressure drop across the orifice. In some embodiments, the downstream edge may include a sharp discontinuity to promote the formation of narrow, high- velocity jets. In some embodiments, the downstream edge may be smoothed, and / or curved, thereby suppressing flow separation and / or stabilizing jet formation.

[0096] In some embodiments, the orifice may be symmetric around at least one axis. For example, the orifice may have a circular or elliptical cross-section exhibiting rotational symmetry. The cross-section may have a dimension characteristic (e.g., a diameter, a length, a width, a circumference, etc.) on the order of microns to hundreds of microns. In some examples, the orifice may have a rectangular cross-section exhibiting reflective symmetry. For example, the orifice may be a slot orifice defined by a long rectangular cross-section where one dimension corresponds to a microscale length (e.g., tens to hundreds of microns). Slot orifices may generate sheet-like jets, which may provide broad cooling areas and enable efficient coverage of elongated heat sources such as linear arrays of semiconductor devices.ALY-020PC

[0097] In some embodiments, the comers of the orifice cross-section may be tapered and / or rounded. The degree of tapering may be varied along different corners of the cross-section. For example, a slot orifice may have tapered comers along one dimension to stabilize sheet flow while maintaining sharp edges along another dimension to preserve jet intensity.

[0098] In some embodiments, the edges of the orifice may be coated, textured, and / or chemically. For example, hydrophobic or oleophobic coatings may be applied to minimize liquid adhesion and produce sharper, more coherent jets. In some examples, textured or roughened edges may be used to break up the jets in a controlled manner.

[0099] In some embodiments, the orifice may be located along the exterior boundary of the part, such that the fluid is discharged outward and directed onto a separate target object. This configuration may enable the part to function as a standalone jetting device that may be positioned adjacent to and / or integrated with a wide range of external objects. The target object may be the heat source itself and / or a thermally conductive interface in contact with the heat source. For example, a plate, a silicon carbide substrate, and / or another conductive object may be placed adjacent to the heat source.

[0100] In some embodiments, surface features may be added to the surface of the target object, such as grooves, fins, and / or textured coatings, to assist heat transfer from the target object. For example, the surfaces may assist in spreading the fluid, directing drainage, and / or promoting nucleate boiling at predetermined sections.

[0101] In some embodiments, the target object may be aligned vertically with respect to gravity so that fluid jetted from the orifices drains downward under gravitational force. Vertical alignment may be advantageous in configurations where fluid is sprayed directly onto the target region and then collected or discharged.

[0102] In some embodiments, the target object may be aligned horizontally or otherwise perpendicular to gravity, such that the jetted fluid flows across the surface of the target object rather than draining directly downward. The target object may include at least one surface feature to assist fluid drainage away from the target object. For example, the surface of the target region may include grooves, channels, ridges, and / or textures that guide fluid toward drainage ports.

[0103] In some embodiments, the orifices may be configured to discharge fluid into a jetting chamber. The jetting chamber may be an internal chamber configured to receive fluid jets. The jetting chamber may be positioned downstream from the orifices.ALY-020PC

[0104] In some embodiments, the jetting chamber may be partitioned into multiple zones, enabling jet impingement in multiple stages. In some embodiments, each zone may be fed by a different orifice.

[0105] In some embodiments, multiple orifices may be configured along the flow path to minimize interaction or interference between adjacent jets in the jetting chamber. The minimization of jet-to-jet interference may enable any number of jets to spray into at least one jetting chamber.

[0106] In some embodiments, multiple jetting chambers may be arranged in series or in parallel with other heat transfer structures, such as microchannels, pin-fins, gyroids, and / or other high specific-surface area structures.

[0107] In some embodiments, at least one orifice may be configured to jet into a jetting chamber. The jetting chamber may be otherwise mechanically or fluidically isolated from adjacent jetting chambers. A self-contained jet impingement structure may consist of an inlet channel, an orifice, a jetting chamber, and / or at least one drainage channel. The self-contained structure may be fluidically connected to other structures in parallel through at least one manifold.

[0108] In some embodiments, a window may be placed on the opposing face of the jetting chamber from the orifices. The window may be a surface for the fluid jets to impinge upon at a fixed distance. The fixed distance may be selected to optimize jet development and / or heat transfer performance. The fixed distance may be on the order of hundreds of microns to several millimeters.

[0109] In some embodiments, the window may be positioned along the external surface of the part, enabling direct thermal contact with the heat source. For example, the window may be bonded, clamped, or otherwise interfaced with the heat source.

[0110] In some embodiments, the window may be formed from a thermally conductive material with a coefficient of thermal expansion (CTE) similar to that of the heat source. This similarity may reduce stress at the interface between the heat source and the part. Suitable materials for the window may include, but are not limited to, copper, graphite, diamond, silicon carbide, aluminum nitride, boron nitride, molybdenum-copper, molybdenum disulfide, tungstencopper, and / or a conductive ceramic material (e.g., oxide ceramic, non-oxide ceramic, silicate ceramic, etc.). In some embodiments, the window may be formed from the same material as the part (e.g., the housing region). In some embodiments, the window may be formed as a composite or layered structure, such as a high-conductivity core bonded to a CTE-matched outer layer.ALY-020PC[OHl] In some embodiments, the target object may include an opening which fluidically connects the heat source to the jetting chamber. The opening may be configured to facilitate jetting directly onto a heat source. The opening may be configured in an appropriate geometry such as a cusp, an elliptical shape, and / or a diamond shape to facilitate force transfer through the metal sheets.

[0112] In some embodiments, the jetting chamber may include at least one outlet port or drainage channel for removing fluid after jet impingement. In some embodiments, multiple ports may be configured to facilitate symmetric fluid removal or to support multi-directional drainage.

[0113] In some embodiments, the surface of the window and / or jetting chamber may be textured to affect the fluid jets and / or enhance heat transfer performance. The texturing may include features such as grooves, dimples, ridges, porous coatings, and / or patterned roughness. The texturing may direct fluid flow toward an outlet port or channel. For example, grooves or channels may be aligned with drainage pathways to guide fluid away from the window. For example, the surface texturing may result in increased surface area for heat transfer and facilitate at least one of fluid mixing and / or boundary layer suppression within the fluid.

[0114] In some embodiments, the texturing may promote nucleate boiling at predetermined locations where the window is in thermal contact with the heat source. Localized roughness or micro-cavities may serve as nucleation sites, stabilizing vapor bubble formation and thereby enhancing two-phase heat transfer.

[0115] In some embodiments, the texturing may be graded or patterned across the window surface, with regions of different surface roughness or pattern density tailored for the thermal load distribution of the heat source. For example, hotter central regions may include dense microcavities to trigger vigorous nucleate boiling, while peripheral regions may include smoother surfaces.

[0116] In some embodiments, the window may be coated with specialized materials, such as hydrophobic coatings to accelerate droplet removal and / or erosion -resistant films to extend operating life under repeated jet impingement.

[0117] In some embodiments, at least one channel may fluidically connect the jetting chamber to a drain manifold. The drain manifold may be a manifold configured to collect fluid after jet impingement and facilitate the removal of fluid from the part. The channel may be positioned to minimize stagnant zones within the jetting chamber and to promote efficient fluid exchange during operation.ALY-020PC

[0118] In some embodiments, the jetting chamber may be configured with a repeating pattern of drain channels and jet orifices such that the jet from each orifice may be drained without fluidically interfering with adjacent jets.

[0119] In some embodiments, a single metal part may house a plurality of jet impingement structures patterned around the heat source. The patterning of the jet impingement structures may be rectangularly packed, hexagonally packed, and / or asymmetrically arranged around hot spots on the heat source. At least one self-contained jet impingement structures may be arranged, in series or in parallel, with other cooling structures such as microchannel arrays, pin-fins, and / or other high surface area structures in the same part.

[0120] In some embodiments, the drain manifold may be configured with at least one external port through which the collected fluid is discharged. The external port may be coupled to an external object, such as a heat exchanger, condenser, piping, reservoir, and / or any other cooling part. The coupling may enable closed-loop recirculation of the fluid throughout the coolant system.

[0121] In some embodiments, the external port may discharge fluid into an open environment, such as in spray-cooling or evaporative systems.

[0122] In some embodiments, the drain manifold may include features such as baffles, slopes, or texturing to affect the drainage flow, such as by guiding fluid efficiently toward the outlet port or preventing accumulation of vapor pockets.

[0123] Figure 1 depicts a cross-section of a part 100 for jet impingement on a heat source 102. The part 100 may be assembled via an additive manufacturing processes using multiple layers bonded together.

[0124] The part 100 may include various internal features for jet impingement, such as a manifold 104, a jet orifice 106, a jetting chamber 108, and a window 110. The manifold 104 may form an upper region of the part 100 and feed fluid into the jet orifice 106. The jet orifice 106 may have a circular cross-section, as shown by the dotted lines. The jet orifice 106 may discharge a fluid jet into the jetting chamber 108 against the window 110, as shown by the dotted arrows. The window 110 may be horizontally oriented and in thermal contact with the heat source 102. The fluid jet may transfer heat away from the heat source 102 and subsequently drain from the jetting chamber 108 (e.g., via an outlet port).

[0125] Figure 2 depicts a cross-section of another part 200 for jet impingement on a heat source 202. As shown, the part 200 may include a manifold 204, a jet orifice 206, a jetting chamber 208, and a window 210. The metal sheets may be oriented orthogonally to the target object to optimizeALY-020PC the efficiency of fluid distribution and return. The manifold 204 may be pressurized with fluid at a given pressure. The manifold 204 may feed fluid into the jet orifice 206. The jet orifice 206 may have a rectangular cross-section and be formed from a cutout in a single layer of the part 200. The target object may be formed as a vertically oriented wall of the part 200 comprising regions of multiple metal sheets adjacent to the heat source 202. The surface of the jetting chamber 208 may include texturing to guide the fluid towards drainage channels and / or ports. The fluid may drain through the drainage channels into at least one fluidically isolated drain manifold.

[0126] Figure 3 depicts a cross-section of yet another part 300 for jet impingement on a heat source 302. As shown, the part 300 may include a manifold 304, a jet orifice 306, a jetting chamber 308, a window 310, and a drainage channel 312. The jet orifice 306 may have a circular crosssection, as shown by the dotted lines. Fluid jetted onto the window 310 may be collected at the sides of the jetting chamber 308. The fluid may then drain out of the jetting chamber 308 via the drainage channel 312.

[0127] The drainage channel 312 may be configured such that the sheets that include sections of the drainage channel may include other fluid regions. The fluid regions may be arranged on the sheets such that the sheets are self-supporting, transmit force well when arranged in a stack, and the fluid regions are separate. This may be accomplished by constructing multiple drainage channels that branch outwards and upwards from the window 310, creating geometries that satisfy the manufacturing constraints of metal LOM parts.

[0128] Figure 4 depicts a cross-section of yet another part 400 for jet impingement on a heat source 402. As shown, the part 400 may comprise various internal features for jet impingement, such as a manifold 404, a jet orifice 406, a jetting chamber 408, a window 410, and an encapsulated orifice plate 412. The orifice plate 412 may be machined to taper the jet orifices 406 to achieve desirable flow characteristics. The part 400 may be manufactured via an additive manufacturing process using multiple layers bonded together. The manufacturing process may include a step where the orifice plate 412 is incorporated into the part 400.

[0129] Figure 5 depicts a flow path 500 of a self-contained jet impingement structure that is mechanically separated from other jet impingement structures. The flow path 500 may include an inlet manifold 502 that supplies fluid through a channel orifice 504 to a jetting chamber 506. The jetting chamber 506 may have at least one drainage channel 508 that connects to a drain manifold 510.ALY-020PC

[0130] In some embodiments, the flow path 500 may be fluidically connected to other jet impingement structures via at least one manifold. Multiple self-contained jet impingement structures may be configured to share the same inlet manifold 502 or the same drain manifold 510.

[0131] Figure 6 depicts a flow path 600 of another self-contained jet impingement structure in a cylindrical section that is mechanically separated from other jet impingement structures. The flow path 600 may include an inlet channel 602 that delivers fluid to an orifice 604, jets the fluid into a jetting chamber 606, and removes the fluid via at least one symmetrical drainage channel 608.

[0132] More complex self-contained jet impingement structures similar to those described in Figures 5 and 6 may have at least one jet, such as no more than nine jets. The drainage channels may be configured such that the sheets containing sections of the drainage channels also contain other fluid regions. The sections of fluid regions may be arranged on the sheets such that the sheets are self-supporting, transmit force evenly when arranged in a stack, and the fluid regions are separate. This may be accomplished by configuring multiple drainage channels which branch away from the target object towards the outlet of the part. The top of the intersection between the jetting chamber and drainage channel may have a cusp. In some embodiments, that cusp may lie below the point where the drainage channel connects with the outlet fluid manifold, creating a self- supporting sheet that satisfies the manufacturing constraints of LOM.Operation

[0133] In embodiments of this invention, the fluid used for jet cooling may include a liquid and / or gas. Examples of gases may include air, nitrogen, helium, argon, and / or any another dielectric gas. Gases may be advantageous where a lower thermal mass and rapid jet velocity provide ideal heat transfer. Examples of liquids may include water, oil, perfluorocarbons, fluorinated ethers, silicone-based oils, and / or any other dielectric liquid. Liquids may provide higher heat capacity and thermal conductivity than gases, enabling greater heat transfer in compact geometries.

[0134] In some embodiments, the part may be configured to use multiple fluid types. For example, a dielectric liquid may be used for normal operation, while a secondary gas or mist may be introduced during periods of high thermal load. Multi-fluid configurations may be implemented with separate manifolds and / or with layered channels for the same manifold. Multiple fluids may be impinged sequentially and / or simultaneously.

[0135] In some embodiments, the fluid may remain entirely in a single phase throughout the jet cooling process. In some embodiments, the fluid may undergo a multi -phase operation. ForALY-020PC example, a liquid jet may impinge on a heated surface, initiating nucleate boiling and phase change. In some examples, a jet of one phase may be sprayed into a bulk fluid of a different phase. For example, a liquid jet may be sprayed into a gaseous environment. In some embodiments, the sprayed fluid and the bulk fluid may have the same composition.

[0136] In some embodiments, the fluid may be impinged as a mist or aerosol jet. For example, an orifice may spray micron-scale droplets with an optional carrier gas.

[0137] In some embodiments, the fluid may be part of a closed configuration. In a closed configuration, the fluid may be continuously pumped through the part and recirculated, thereby conserving fluid and enabling steady-state operation. The outflow may be routed to an external component, where it may be cooled before being return to an inlet port. In an open configuration, the fluid may be sprayed onto the target region and subsequently cleared (e.g., drained or evaporated away), which may simplify system integration at the expense of higher fluid consumption. In some embodiments, the fluid may be part of a hybrid configuration, where a portion of the fluid is part of a closed loop while another portion is part of an open configuration.

[0138] In some embodiments, the part may operate with traditional cooling parts, such as vapor chambers, heat pipes, and / or finned heat sinks. For example, the part may be coupled to a vapor chamber, where the jets remove heat from a localized hot spot while the vapor chamber redistributes the residual heat over a broader surface for passive dissipation.Equivalents

[0139] The methods, systems, and devices discussed above are examples. Various configurations may omit, substitute, or add various procedures or components as appropriate. For instance, in alternative configurations, the methods may be performed in an order different from that described, and that various steps may be added, omitted, or combined. Also, features described with respect to certain configurations may be combined in various other configurations. Different aspects and elements of the configurations may be combined in a similar manner. Also, technology evolves and, thus, many of the elements are examples and do not limit the scope of the disclosure or claims.

[0140] Embodiments of the present disclosure, for example, are described above with reference to block diagrams and / or operational illustrations of methods, systems, and computer program products according to embodiments of the present disclosure. The functions / acts noted in the blocks may occur out of the order as shown in any flowchart. For example, two blocks shown in succession may in fact be executed substantially concurrent or the blocks may sometimes be executed in the reverse order, depending upon the functionality / acts involved. Additionally, orALY-020PC alternatively, not all of the blocks shown in any flowchart need to be performed and / or executed. For example, if a given flowchart has five blocks containing functions / acts, it may be the case that only three of the five blocks are performed and / or executed. In this example, any of the three of the five blocks may be performed and / or executed.

[0141] A statement that a value exceeds (or is more than) a first threshold value is equivalent to a statement that the value meets or exceeds a second threshold value that is slightly greater than the first threshold value, e.g., the second threshold value being one value higher than the first threshold value in the resolution of a relevant system. A statement that a value is less than (or is within) a first threshold value is equivalent to a statement that the value is less than or equal to a second threshold value that is slightly lower than the first threshold value, e.g., the second threshold value being one value lower than the first threshold value in the resolution of the relevant system.

[0142] Specific details are given in the description to provide a thorough understanding of example configurations (including implementations). However, configurations may be practiced without these specific details. This description provides example configurations only, and does not limit the scope, applicability, or configurations of the claims. Rather, the preceding description of the configurations will provide those skilled in the art with an enabling description for implementing described techniques. Various changes may be made in the function and arrangement of elements without departing from the spirit or scope of the disclosure.

[0143] Having described several example configurations, various modifications, alternative constructions, and equivalents may be used without departing from the spirit of the disclosure. For example, the above elements may be components of a larger system, wherein other rules may take precedence over or otherwise modify the application of various implementations or techniques of the present disclosure. Also, a number of steps may be undertaken before, during, or after the above elements are considered.

Claims

ALY-020PCCLAIMSWhat is claimed is:

1. A metal part comprising: a housing region; and at least one internal plumbing feature encapsulated by the housing region and configured to cool a heat source via a fluid, wherein the internal plumbing feature comprises at least one of an internal channel, a delivery manifold, a drain manifold, a void space configured to flow the fluid, a jet orifice configured to jet the fluid, or a target object to receive the jetted fluid.

2. The metal part of claim 1 wherein the metal part comprises a single-build part formed without welding separate components together.

3. The metal part of claim 1 wherein the jet orifice is configured to jet the fluid on at least one of the heat source or a thermally conductive window via a jetting chamber.

4. The metal part of claim 3 wherein the window is placed along an external surface of the part and is in thermal contact with the heat source.

5. The metal part of claim 3 wherein the internal channel fluidically connects the jetting chamber to the manifold for draining the fluid after jetting.

6. The metal part of claim 1 wherein the internal channel originates at the manifold and terminates at the jet orifice.

7. The metal part of claim 1 wherein the jet orifice has the same diameter as the internal channel.

8. The metal part of claim 1 wherein the housing region comprises at least one port for enabling the fluid to flow into or out of the metal part.

9. The metal part of claim 8 wherein the at least one port comprises an inlet port and an outlet port, wherein the inlet port is configured to mate with a fluid source.

10. The metal part of claim 1 wherein the metal part further comprises a plurality of jet impingement structures comprising the at least one internal plumbing feature, and wherein atALY-020PC least one of the jet impingement structures is mechanically separated from at least one other jet impingement structure.

11. The metal part of claim 1 wherein the at least one internal plumbing feature comprises an encapsulated orifice plate terminating at the jet orifice.

12. The metal part of claim 1 wherein the metal part is manufactured via an additive manufacturing process.

13. A method for forming a metal part via an additive manufacturing process, the method comprising: patterning a plurality of metal sheets; stacking the patterned metal sheets; and bonding the stacked metal sheets to form the metal part, the metal part comprising: a housing region; and at least one internal plumbing feature encapsulated by the housing region and configured to cool a heat source via a fluid, wherein the internal plumbing feature comprises at least one of an internal channel, a delivery manifold, a drain manifold, a void space configured to flow the fluid, a jet orifice configured to jet the fluid, or a target object to receive the jetted fluid.

14. The method of claim 13 wherein the jet orifice is configured to jet the fluid on at least one of the heat source or a thermally conductive window via a jetting chamber.

15. The method of claim 13 wherein the internal channel originates at the manifold and terminates at the jet orifice.

16. The method of claim 13 wherein the jet orifice has the same diameter as the internal channel.

17. The method of claim 13 wherein the housing region comprises at least one port for enabling the fluid to flow into or out of the metal part.

18. The method of claim 13 wherein the housing region comprises at least one mounting component for interfacing with a cooling system.ALY-020PC19. The method of claim 13 wherein the heat source is aligned orthogonally with respect to the plurality of metal sheets during operation.

20. A system for forming a metal part via an additive manufacturing process, the system comprising: an additive object manufacturing device configured to: pattern a plurality of metal sheets; and stack the patterned metal sheets; and a pressor configured to bond the stacked metal sheets by applying a mechanical force for forming the metal part, the metal part comprising: a housing region; and at least one internal plumbing feature encapsulated by the housing region and configured to cool a heat source via a fluid, wherein the internal plumbing feature comprises at least one of an internal channel, a delivery manifold, a drain manifold, a void space configured to flow the fluid, a jet orifice configured to jet the fluid, or a target object to receive the jetted fluid.

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