Patent Application
20200095889
Additive manufacturing processes or systems can be used to print or build three-dimensional parts or components from digital models, which can be beneficial for rapid prototyping and manufacturing. During manufacture of the component, support structures may be included within the part to provide added rigidity for partially-formed portions. Such support structures are typically removed from the completed component after manufacture. In some cases the completed component can fully enclose an interior space, where removal of interior support structures can be difficult, impractical or even impossible.
In one aspect, the disclosure relates to a heat-carrying component including an outer casing bounding an interior, a conduit located within the interior, and a support structure located within the interior and having at least two thermally-conductive support members supporting the conduit, with the at least two support members being spaced apart to define at least two fins which collectively form a heat exchanger thermally coupled to the conduit.
In another aspect, the disclosure relates to a turbine engine having a compressor, a combustor, and a turbine in axial flow arrangement, including an additively-manufactured component within the turbine engine. The additively-manufactured component can include an outer casing bounding an interior and defining an exteriorly inaccessible portion within the interior, a conduit located within the interior and having at least a portion within the exteriorly inaccessible portion, and an additive support structure located within the exteriorly inaccessible portion and having at least two thermally-conductive support members supporting the conduit during an additive manufacturing process, with the at least two support members being spaced apart to define at least two fins which collectively form a heat exchanger thermally coupled to the conduit.
In yet another aspect, the disclosure relates to a method of cooling a monolithic heat-carrying component having an outer casing bounding an interior. The method includes flowing heat-carrying fluid through a conduit unitarily formed with the outer casing and located within the interior, and transferring heat from the heat-carrying fluid to a support structure thermally coupled to the conduit and located within the interior, the support structure having at least two spaced fins which collectively form a heat exchanger.
In the drawings:
Aspects of the present disclosure relate to a heat-carrying component, and examples of such a component are described herein in the context of a turbine engine and gearbox. It will be understood that the disclosure may have general applicability within an engine, including turbines and compressors and non-airfoil engine components, as well as in non-aircraft applications, such as other mobile applications and non-mobile industrial, commercial, and residential applications.
All directional references (e.g., radial, upper, lower, upward, downward, left, right, lateral, front, back, top, bottom, above, below, vertical, horizontal, clockwise, counterclockwise) are only used for identification purposes to aid the reader's understanding of the disclosure, and do not create limitations, particularly as to the position, orientation, or use thereof. Connection references (e.g., attached, coupled, connected, and joined) are to be construed broadly and can include intermediate members between a collection of elements and relative movement between elements unless otherwise indicated. As such, connection references do not necessarily infer that two elements are directly connected and in fixed relation to each other. The exemplary drawings are for purposes of illustration only and the dimensions, positions, order, and relative sizes reflected in the drawings attached hereto can vary.
As used herein, the term “forward” or “upstream” refers to moving in a direction toward the engine inlet, or a component being relatively closer to the engine inlet as compared to another component. The term “aft” or “downstream” refers to a direction toward the rear or outlet of the engine relative to the engine centerline. Additionally, as used herein, the terms “radial” or “radially” refer to a dimension extending between a center longitudinal axis of the engine and an outer engine circumference. It should be further understood that “a set” can include any number of the respectively described elements, including only one element.
An exemplary turbine engine 10 is illustrated in
The high pressure compression region 14 provides a combustion chamber 16 with high pressure air. In the combustion chamber 16, the high pressure air is mixed with fuel and combusted. The hot and pressurized combusted gases pass through a high pressure turbine region 18 and a low pressure turbine region 20 before exhausting from the turbine engine 10.
As the pressurized gases pass through the high pressure turbine (not shown) of the high pressure turbine region 18 and the low pressure turbine (not shown) of the low pressure turbine region 20, the turbines extract rotational energy from the flow of the gases passing through the turbine engine 10. The high pressure turbine of the high pressure turbine region 18 can be coupled to the compression mechanism (not shown) of the high pressure compression region 14 by way of a shaft to power the compression mechanism. The low pressure turbine can be coupled to the fan 12 of the air intake by way of a shaft to power the fan 12. The turbine engine can also have an afterburner that burns an additional amount of fuel downstream of the low pressure turbine region 20 to increase the velocity of the exhausted gases, and thereby increasing thrust. In this manner the turbine engine 10 can include at least a compressor, combustor, and turbine in axial flow arrangement.
An air turbine starter or generator 25 can be mounted to the turbine engine 10. An accessory gearbox (AGB) 40, also referred to herein as “gearbox 40,” can be coupled to the generator 25 and mounted to the turbine engine 10. Together, the generator 25 and gearbox 40 can define an assembly which is commonly referred to as an Integrated Starter/Generator Gearbox (ISGB) 44.
The generator 25 and gearbox 40 can be selectively operably coupled with the turbine engine 10 at either the high pressure or low pressure turbine region 18, 20 by way of a mechanical power take-off 42. The mechanical power take-off 42 contains multiple gears and means for mechanical coupling of the gearbox 40 to the turbine engine 10. Under normal operating conditions, the power take-off 42 translates power from the turbine engine 10 to the gearbox 40 to power accessories of the aircraft for example but not limited to fuel pumps, electrical systems, and cabin environment controls. The generator 25 can be mounted on the outside of either the air intake region containing the fan 12 or on the core near the high pressure compression region 18.
The turbine engine 10 can include at least one heat-carrying component 50 (also referred to herein as “component 50”). It is contemplated that the heat-carrying component 50 can be an additively manufactured component. As used herein, an “additively manufactured” component will refer to a component formed by an additive manufacturing (AM) process, wherein the component is built layer-by-layer by successive deposition of material. AM is an appropriate name to describe the technologies that build 3D objects by adding layer-upon-layer of material, whether the material is plastic or metal. AM technologies can utilize a computer, 3D modeling software (Computer Aided Design or CAD), machine equipment, and layering material. Once a CAD sketch is produced, the AM equipment can read in data from the CAD file and lay down or add successive layers of liquid, powder, sheet material or other material, in a layer-upon-layer fashion to fabricate a 3D object. It should be understood that the term “additive manufacturing” encompasses many technologies including subsets like 3D Printing, Rapid Prototyping (RP), Direct Digital Manufacturing (DDM), layered manufacturing and additive fabrication. Non-limiting examples of additive manufacturing that can be utilized to form an additively-manufactured component include powder bed fusion, vat photopolymerization, binder jetting, material extrusion, directed energy deposition, material jetting, or sheet lamination.
Turning to
The completed additively-manufactured generator housing 30 is illustrated in a cross-sectional view. An exemplary base plate 56 is shown beneath the generator housing 30 that can be utilized during an additive manufacturing process to form the generator housing 30. The generator housing 30 can be built or printed layer-by-layer, illustrated with exemplary layers 57 intersecting the completed generator housing 30 wherein successive layers 57 are added in a direction illustrated by a direction arrow 58. It should be understood that other components such as exterior supporting arms, a printing head, and the like can be utilized during the additive manufacturing process and are omitted for clarity.
The generator housing 30 can include an outer casing 52 bounding an interior 54. It can also be appreciated that the outer casing 52 of the completed generator housing 30 can define an exteriorly inaccessible portion 55 (also referred to herein as “inaccessible portion 55”) within the interior 54. As used here, an “exteriorly inaccessible portion” of a component will refer to a portion that cannot be accessed from outside the component, such as by hand and/or with tools, for performing operations such as machining or assembly within the component. Such an exteriorly inaccessible portion can also be fluidly separated from the exterior of the component, such as being airtight or watertight, although this need not be the case. In addition, while the outer casing 52 is illustrated as rectangular or box-like, it is also contemplated that the outer casing 52 can be curved to match an exterior surface 11 of the turbine engine 10 (
At least one conduit 61 can be located within the interior 54, and at least a portion 60 of the conduit 61 can be located within the inaccessible portion 55. The conduit 61 can be configured to direct fluids or coolant, including oil, through the generator 25 during operation of the turbine engine 10. It is also contemplated that the conduit 61 can be unitarily formed with the outer casing 52.
It can be appreciated that support structures can be utilized to support various components within the generator housing 30, including during additive manufacture of the generator housing 30. For example, the use of such support structures can prevent shifting or other undesired movement of components within the outer casing 52 during manufacture or during operation of the turbine engine 10. One such example is illustrated as a first additive support structure 70 supporting the conduit 61. The first additive support structure 70 can be coupled to, or unitarily formed with, the conduit 61 as shown. The first additive support structure 70 can have any desired shape, size, or thickness. In an example where the generator housing 30 is formed by additive manufacturing, it is further contemplated that the generator housing 30 can include a monolithic body having the outer casing 52, the conduit 61, and a support structure such as the first additive support structure 70.
A second conduit 62 similar to the conduit 61 can also be coupled to the first additive support structure 70. More specifically, the second conduit 62 can be thermally coupled to the fins 74 of the heat exchanger 76 defined by the first additive support structure 70.
In addition, a second additive support structure 80 similar to the first additive support structure 70 is illustrated between the outer casing 52 and the second conduit 62. It is contemplated that the second additive support structure 80 can also define a second heat exchanger 86 similar to the heat exchanger 76 and having a plurality of fins 84. The fins 84 can be thermally coupled to both the outer casing 52 and the second conduit 62 as shown. In this manner, a single conduit within the generator housing 30 can have multiple heat exchangers formed by corresponding multiple support structures as desired.
In still another example, a third additive support structure 90 similar to the additive support structure 70 can be coupled to a third conduit 63 and the outer casing 52. It will be understood that a plurality of additive support structures can be utilized within the generator housing 30 and coupled between conduits, or coupled between a conduit and the outer casing, or coupled to any component within the generator housing 30, in non-limiting examples.
Turning to
It is also contemplated that the fins 74 can include cooling enhancement structures configured to improve cooling performance of the heat exchanger 76. One cooling enhancement structure is illustrated in the form of an aperture or hole 78 through a first fin 74A, where air in adjacent cooling channels 77 can flow through the first fin 74A to increase a rate of heat transfer from the first fin 74A. Another cooling enhancement structure is illustrated in the form of dimples 79 in the surface of a second fin 74B. Such dimples 79 can increase the surface area of the second fin 74B and increase a rate of heat transfer from the fin 74B as compared to a smooth fin 74. Other cooling enhancement structures can be in the form of local surface roughness, latticed structures, or cutouts can be included in any of the additive support structures 70, 80 forming the heat exchangers 76, 86.
During operation, heat-carrying fluid 35 such as oil can flow through any or all of the conduits 61, 62, 63. In one example, a first heat-carrying fluid can flow through the conduit 61 while additional or second heat-carrying fluid flows through the second conduit 62. In another example, the same heat-carrying fluid can flow through all of the conduits 61, 62, 63.
Arrows 101 (
It can be appreciated that heat can also transfer away from the interior 54 of the generator housing 30 via the outer casing 52. In another example, a plurality of vent holes (not shown) can be provided in the outer casing 52 to facilitate the transfer of heat from the interior 54 of the generator housing 30. Such vent holes can be integrally formed with the outer casing 52, and can be of a size that does not permit access to the interior 54 with tools or other devices while permitting air to flow into or out of the interior 54.
Aspects of the present disclosure provide for a method of cooling a monolithic heat-carrying component such as the component 50 having the outer casing 52 bounding the interior 54. The method can include moving heat-carrying fluid 35 through a conduit, such as the conduit 61, 62, 63, located within the interior 54 and unitarily formed with the outer casing 52. The method can also include transferring heat from the heat-carrying fluid 35 to an additively-manufactured support structure, such as the first or second additive support structures 70, 80 (
The above described aspects provide for a variety of benefits. For power generator parts manufactured by additive printing technology, support structures utilized within exteriorly inaccessible spaces during printing cannot be removed (e.g. machined out). The use of fins as support structures can reduce the weight of the additively-manufactured component while adding improved functionality such as cooling, which can increase performance or efficiency during operation of the additively-manufactured component. In addition, the improved ability to cool such exteriorly inaccessible regions can increase the working lifetime of the part.
To the extent not already described, the different features and structures of the various aspects can be used in combination with each other as desired. That one feature cannot be illustrated in all of the aspects is not meant to be construed that it cannot be, but is done for brevity of description. Thus, the various features of the different aspects can be mixed and matched as desired to form new examples, whether or not the new examples are expressly described. Combinations or permutations of features described herein are covered by this disclosure. Many other possible embodiments and configurations in addition to that shown in the above figures are contemplated by the present disclosure.
This written description uses examples to disclose aspects of the invention, including the best mode, and also to enable any person skilled in the art to practice aspects of the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and can include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.
