Fairing assembly

Abstract

A cowl assembly and a method for assembling a gas turbine engine cowl assembly are provided. For example, the cowl assembly includes a plurality of cowls, an annular inner band defining a plurality of inner notches, and an annular outer band defining a plurality of outer notches. Each cowl has an inner end radially spaced from an outer end. Each inner notch is shaped complementary to the inner end of each cowl and has a forward end and a rearward end. Each outer notch is shaped complementary to the outer end of each cowl and has a forward end and a rearward end. The inner band and the outer band are each a single piece construction. Each cowl inner end is received within one of the plurality of inner notches, and each cowl outer end is received within one of the plurality of outer notches. Some embodiments further include an inner ring positioned against the inner band to close the inner notches.

Description

Technical Field

[0001] This topic generally relates to gas turbine engines. More specifically, this topic relates to airfoil assemblies for gas turbine engines, such as fairing assemblies. Most specifically, this topic relates to composite fairing assemblies. Background Technology

[0002] More commonly, non-traditional high-temperature composite materials, such as ceramic matrix composites (CMC), are being used in applications such as gas turbine engines. Components made from this material have higher temperature resistance compared to typical components (e.g., metal components), which can allow for improved component performance and / or increased engine temperatures. Composite components can also offer other advantages, such as an improved strength-to-weight ratio.

[0003] Typically, a CMC turbine nozzle cowling comprises an airfoil, an inner belt, and an outer belt, integrally formed as a single component, which is axially divided into front and rear sections and circumferentially divided into multiple segments. These multiple segments together form an annular cowling assembly, and dividing the assembly into front and rear sections allows the airfoil portion to be mounted around structural elements of the turbine frame, such as struts. While dividing the cowling assembly into sections and segments enables assembly with the turbine frame, having both front and rear sections for each of the multiple sections increases the number of components for the cowling assembly. Furthermore, the separation of components increases the possibility of leakage, for example, between each circumferential cowling segment, which may also require increasing the number of components to attempt to prevent such leakage by requiring seals or other mechanisms. Additionally, the thermal difference between the airfoil and the belt, i.e., thermal fight, generates high stress within the nozzle cowling, which limits the acceptability of component defects and leads to stricter inspection limitations for non-destructive testing of the components.

[0004] Therefore, an improved fairing assembly would be useful. In particular, it would be advantageous for the fairing assembly to include multiple fairing airfoils, each separated from each of the annular one-piece inner and outer belts. Furthermore, a fairing assembly having one-piece annular inner and outer belts suitable for use with multiple turbine frame configurations is desirable. Summary of the Invention

[0005] Aspects and advantages of the invention will be set forth in part in the description which follows, or may be apparent from the description, or may be learned by practice of the invention.

[0006] In one exemplary embodiment of this subject matter, a cowling assembly for a gas turbine engine is provided. The cowling assembly includes a plurality of cowlings; an annular inner band defining a plurality of pockets; and an annular outer band defining a plurality of outer pockets. Each cowling has an inner end radially spaced from an outer end and extends axially from a leading edge to a trailing edge. Each pocket is complementary to the inner end of each cowling and has a front end and a rear end. Each outer pocket is complementary to the outer end of each cowling and has a front end and a rear end. The inner band is a one-piece structure, and the outer band is a one-piece structure. The inner end of each cowling is received within a pocket of the plurality of pockets, and the outer end of each cowling is received within an outer pocket of the plurality of outer pockets.

[0007] In another exemplary embodiment of this subject matter, a cowling assembly for a gas turbine engine is provided. The cowling assembly includes a plurality of cowlings, an inner ring defining a plurality of recessed front sections, an annular inner band defining a plurality of recessed rear sections, and an annular outer band defining a plurality of recesses. Each cowling has an inner end radially spaced from an outer end and extends axially from a leading edge to a trailing edge. The inner ring is positioned against the leading edge of the inner band such that the recessed front and rear sections form a plurality of recesses. Each recess is complementary to the inner end of each cowling and has a front end and a rear end. Furthermore, each recess is complementary to the outer end of each cowling and has a front end and a rear end. The inner ring is a one-piece structure, the inner band is a one-piece structure, and the outer band is a one-piece structure. The inner end of each cowling is received within a recess of the plurality of recesses, and the outer end of each cowling is received within a recess of the plurality of recesses.

[0008] In another exemplary embodiment of this subject matter, a method for assembling a cowling assembly in a gas turbine engine is provided. The method includes mounting an annular inner belt in the gas turbine engine. The inner belt defines a plurality of recesses. The method further includes inserting an inner end of each of a plurality of cowlings into a recess among the plurality of recesses. The method further includes sliding an annular outer belt about the plurality of cowlings such that an outer end of each of the plurality of cowlings is received in an outer recess among the plurality of outer recesses defined by the outer belt. The inner belt is a one-piece structure, and the outer belt is a one-piece structure.

[0009] These and other features, aspects, and advantages of the invention will become more readily understood with reference to the following description and the appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

[0010] Technical Solution 1. A cowling assembly for a gas turbine engine, comprising:

[0011] Multiple fairings, each fairing having an inner end radially spaced from an outer end, each fairing extending axially from a leading edge to a trailing edge;

[0012] An annular inner band defines multiple recesses, each recess complementary to the inner end of each fairing, and each recess has a front end and a rear end; and

[0013] An annular outer band defines multiple outward notches, each notch complementary to the outer band forming of each fairing, and each outward notch having a front end and a rear end.

[0014] The inner belt is a single-piece structure.

[0015] The outer strap is a single-piece structure, and

[0016] The inner end of each fairing is received by an inner recess among multiple inner recesses, and the outer end of each fairing is received within an outer recess among multiple outer recesses.

[0017] Technical Solution 2. The fairing assembly according to any of the foregoing technical solutions, wherein the inner strip surrounds each recess such that each recess is closed at the front end and the rear end.

[0018] Technical Solution 3. The fairing assembly according to the foregoing technical solution, wherein the outer band surrounds each outer notch such that each outer notch is closed at the front end and the rear end.

[0019] Technical Solution 4. The fairing assembly according to the foregoing technical solution, wherein each recess is open at the front end and closed at the rear end.

[0020] Technical Solution 5. The fairing assembly according to the foregoing technical solution further includes:

[0021] The inner ring is positioned against the front edge of the inner band to close the front end of each recess.

[0022] Technical Solution 6. The fairing assembly according to the foregoing technical solution, wherein each external notch is open at the front end and closed at the rear end.

[0023] Technical Solution 7. The fairing assembly according to the foregoing technical solution further includes:

[0024] The outer ring is positioned at the front flange of the outer band to close the front end of each outer notch.

[0025] Technical Solution 8. The fairing assembly according to the foregoing technical solution, wherein the plurality of fairings, the inner belt and the outer belt are each formed of a ceramic matrix composite material.

[0026] Technical Solution 9. A cowling assembly for a gas turbine engine, comprising:

[0027] Multiple fairings, each fairing having an inner end radially spaced from an outer end, each fairing extending axially from a leading edge to a trailing edge;

[0028] The inner ring defines the front section of multiple inwardly recessed openings;

[0029] An annular inner band defining a plurality of recessed rear sections, the inner ring being positioned abutting against the front edge of the inner band such that the front and rear recessed sections form a plurality of recesses, each recess being complementary to the inner end of each fairing, and each recess having a front end and a rear end; and

[0030] An annular outer band defines multiple outward notches, each notch complementary to the outer end of each fairing, and each notch has a front end and a rear end.

[0031] The inner ring is a single-piece structure.

[0032] The inner belt is a single-piece structure.

[0033] The outer strap is a single-piece structure, and

[0034] The inner end of each fairing is received by an inner recess among multiple inner recesses, and the outer end of each fairing is received within an outer recess among multiple outer recesses.

[0035] Technical Solution 10. The fairing assembly according to the foregoing technical solution further includes:

[0036] Outer ring,

[0037] The outer ring is a single-piece structure.

[0038] Each of the external notches is open at the front end and closed at the rear end.

[0039] The outer ring is positioned at the front flange of the outer band to close the front end of each outer notch.

[0040] Technical Solution 11. The fairing assembly according to the foregoing technical solution, wherein at least one fairing is axially separated and includes a front section and a rear section.

[0041] Technical Solution 12. The fairing assembly according to the foregoing technical solution, wherein at least one fairing is circumferentially separated and includes a first side section and a second side section.

[0042] Technical Solution 13. The fairing assembly according to the foregoing technical solution, wherein each recess includes a lip extending around the recess, and wherein an inner end of each fairing is received within the recess such that the inner end contacts the lip.

[0043] Technical Solution 14. The fairing assembly according to the foregoing technical solution, wherein each outer recess includes a lip extending around the outer recess, and wherein an outer end of each fairing is received within the outer recess such that the outer end contacts the lip.

[0044] Technical Solution 15. The fairing assembly according to the foregoing technical solution further includes:

[0045] Multiple seals,

[0046] Among the multiple seals, the seal is positioned between the outer end of each fairing and the outer belt.

[0047] Each of the plurality of seals includes a curved arm that is compressed between the outer end of the fairing and the outer belt.

[0048] Each of the plurality of seals includes at least one flat wear surface between the outer end of the fairing and the outer belt.

[0049] Technical Solution 16. The fairing assembly according to the foregoing technical solution further includes:

[0050] Multiple seals,

[0051] Among the multiple seals, the seal is positioned between the inner end of each fairing and the inner belt.

[0052] Each of the plurality of seals includes a curved arm that is compressed between the inner end of the fairing and the inner belt, and

[0053] Each of the plurality of seals includes at least one worn surface of a plane between the inner end of the fairing and the inner belt.

[0054] Technical Solution 17. The fairing assembly according to the foregoing technical solution, wherein a plurality of fairings are pinned to the inner end of each fairing by a plurality of pins, each of the plurality of pins extending between the inner end of one of the fairings and the inner strip.

[0055] Technical Solution 18. The fairing assembly according to the foregoing technical solution, wherein a plurality of fairings, the inner belt and the outer belt are each formed of a ceramic matrix composite material.

[0056] Technical Solution 19. The fairing assembly according to the foregoing technical solution further includes:

[0057] A non-through-hole defined in a component of the fairing assembly, the non-through-hole gradually tapers outward along its side near its closed distal end; and

[0058] An angled washer is inserted into the non-through hole, the angled washer having an angled end that fits within the tapered distal end of the non-through hole.

[0059] Technical Solution 20. The fairing assembly according to the foregoing technical solution further includes:

[0060] A non-through hole, which is confined within the first component;

[0061] An opening, which is defined in the second component;

[0062] Washer, which is fixed in the non-through hole;

[0063] Forged washers, which are fixed in the opening; and

[0064] A pin, which is inserted into the opening defined by the washer and the forged washer,

[0065] The pin is welded to the forged washer.

[0066] Technical Solution 21. The fairing assembly according to the foregoing technical solution, wherein the gasket is an unfolded gasket having a distal end with a cross-section larger than the body of the gasket.

[0067] Technical Solution 22. The fairing assembly according to the foregoing technical solution further includes:

[0068] A non-through hole, which is confined within the first component;

[0069] An opening, which is defined in the second component; and

[0070] Washers, which are fixed in the non-through holes and the openings,

[0071] The washer is an unfolded washer having a distal end with a cross-section larger than the body of the washer.

[0072] The body of the washer extends through the opening in the second component, and

[0073] The proximal end of the washer is forged around a fastener inserted into the washer to retain the fastener with respect to the washer.

[0074] Technical Solution 23. A method for assembling a cowling assembly in a gas turbine engine, the method comprising:

[0075] An annular inner band is installed in a gas turbine engine, the inner band defining a plurality of recesses;

[0076] Insert the inner end of each of the multiple fairings into the inner recess of the multiple recesses; and

[0077] The annular outer band is slidably positioned relative to the plurality of fairings, such that the outer end of each of the plurality of fairings is received in an outer recess of one of the plurality of outer recesses defined by the outer band.

[0078] The inner belt is a single-piece structure, and

[0079] The outer belt is a single-piece structure.

[0080] Technical Solution 24. The method according to the foregoing technical solution, wherein the outer belt slides into place from the front end of the fairing assembly toward the rear end of the fairing assembly. Attached Figure Description

[0081] The complete and practicable disclosure of the present invention, including its best mode, is set forth in this specification for those skilled in the art, with reference to the accompanying drawings, wherein:

[0082] Figure 1 A schematic cross-sectional view of an exemplary gas turbine engine according to various embodiments of this subject is provided.

[0083] Figure 2A and 2B A schematic cross-sectional view of a fairing assembly according to an exemplary embodiment of this subject is provided.

[0084] Figure 3 Provided Figure 2A or Figure 2B A perspective view of the fairing assembly.

[0085] Figure 4 Provided Figure 2A or Figure 2B Exploded perspective view of the inner and outer bands of the fairing assembly.

[0086] Figure 5 Provided Figure 2A or Figure 2B A perspective view of the fairing airfoil of the fairing assembly.

[0087] Figure 6A and 6B A schematic cross-sectional view of a fairing assembly according to an exemplary embodiment of this subject is provided.

[0088] Figure 7 Provided Figure 6AA perspective view of the fairing assembly.

[0089] Figure 8 Provided Figure 6A Exploded perspective view of the inner band and inner ring of the fairing assembly.

[0090] Figure 9 A schematic cross-sectional view of a fairing assembly according to an exemplary embodiment of this subject is provided.

[0091] Figure 10 Provided Figure 9 A perspective view of the fairing assembly.

[0092] Figure 11 Provided Figure 9 Exploded perspective view of the outer band and outer ring of the fairing assembly.

[0093] Figure 12 An exploded perspective view of an axially separated fairing airfoil according to an exemplary embodiment of this subject is provided.

[0094] Figure 13 A schematic cross-sectional view of a circumferentially separated fairing airfoil is provided according to exemplary embodiments of this subject matter.

[0095] Figure 14 A perspective view of a portion of a fairing assembly according to an exemplary embodiment of this subject is provided.

[0096] Figure 15 , 16 Figures 17 and 18 provide radial cross-sectional views of a portion of the outer end of the fairing and the outer band notch according to various exemplary embodiments of the subject matter, wherein a seal is positioned therebetween.

[0097] Figure 18A A perspective view is provided of the pins used to pin the fairing airfoil to the fairing assembly.

[0098] Figure 18B Exemplary embodiments according to this topic are provided having, as Figure 18A The image shows an axial cross-sectional view of the separate fairing airfoil receiving two pins therein.

[0099] Figure 19 A schematic cross-sectional view of a fairing assembly with pinned fairing airfoil elements according to exemplary embodiments of this subject is provided.

[0100] Figure 20A , 20B Figures 21-24 provide schematic cross-sectional views of various exemplary embodiments of grommets and fastener constructions according to the subject matter of the invention.

[0101] Figure 25 , 26 27 and 28 provide flowcharts illustrating various exemplary embodiments of a method for assembling a cowling assembly in a gas turbine engine, based on the subject matter of the invention. Detailed Implementation

[0102] Reference will now be made in detail to embodiments of the invention, one or more of which are illustrated in the accompanying drawings. Detailed descriptions use numbers and letters to denote features in the figures. The same or similar names in the figures and descriptions have been used to refer to the same or similar parts of the invention.

[0103] As used in this article, the terms “first,” “second,” and “third” are used interchangeably to distinguish one component from another and are not intended to indicate the position or importance of a single component.

[0104] The terms "front" and "rear" refer to relative positions within a gas turbine engine or vehicle, and specifically to the normal operating posture of the gas turbine engine or vehicle. For example, regarding a gas turbine engine, "front" refers to the position closer to the engine inlet, while "rear" refers to the position closer to the engine nozzle or exhaust port.

[0105] The terms "upstream" and "downstream" refer to the relative directions of fluid flow within a fluid path. For example, "upstream" refers to the direction from which the fluid flows, while "downstream" refers to the direction to which the fluid flows.

[0106] The terms “connection,” “fixation,” “attachment,” etc., refer to direct connection, fixation, or attachment, as well as indirect connection, fixation, or attachment through one or more intermediate components or features, unless otherwise specified herein.

[0107] The singular forms “a,” “an,” and “the” include the plural reference unless the context clearly specifies otherwise.

[0108] The approximate language used throughout this specification and claims is intended to modify any quantitative expression that may vary without altering its underlying function. Therefore, values ​​modified by one or more terms such as “approximately,” “about,” and “substantially” are not limited to the specified exact values. In at least some cases, approximate language may correspond to the precision of the instrument used to measure the value, or the precision of the method or machine used to construct or manufacture the component and / or system. For example, approximate language might refer to a margin of 10%.

[0109] Throughout this specification and claims, scope limitations are combined and interchanged, and such scope is definite and includes all subscopes contained therein, unless otherwise indicated by context or language. For example, all scopes disclosed herein include endpoints, and endpoints may be combined independently of each other.

[0110] Referring now to the accompanying drawings, where the same reference numerals denote the same elements throughout the drawing, Figure 1 This is a schematic cross-sectional view of a gas turbine engine according to an exemplary embodiment of the present disclosure. More specifically, for Figure 1 In one embodiment, the gas turbine engine is a high-bypass turbofan jet engine 10, referred to herein as "turbofan engine 10". Figure 1 As shown, the turbofan engine 10 defines an axial direction A (extending parallel to the longitudinal centerline 12 provided for reference) and a radial direction R. Typically, the turbofan 10 includes a fan section 14 and a core turbine engine 16 disposed downstream of the fan section 14.

[0111] An exemplary core turbine engine 16 typically depicted includes a generally cylindrical casing 18 defining an annular inlet 20. The casing 18 surrounds, in a flow-through relationship, a compressor section including a boost or low-pressure (LP) compressor 22 and a high-pressure (HP) compressor 24; a combustion section 26; a turbine section including a high-pressure (HP) turbine 28 and a low-pressure (LP) turbine 30; and an exhaust nozzle section 32. A high-pressure (HP) shaft or reel 34 is drivably connected to the HP turbine 28 and the HP compressor 24. A low-pressure (LP) shaft or reel 36 is drivably connected to the LP turbine 30 and the LP compressor 22.

[0112] In the depicted embodiment, fan section 14 includes a fan 38 having a plurality of fan blades 40 spaced apart and coupled to disk 42. As depicted, the fan blades 40 generally extend outward from disk 42 in a radial direction R. The blades 40 and disk 42 together can be rotated about longitudinal axis 12 via LP shaft 36. In some embodiments, a power gearbox with a plurality of gears may be included for reducing the rotational speed of LP shaft 36 to a more efficient fan rotation speed.

[0113] Still referencing Figure 1 An exemplary embodiment. For example... Figure 1As shown, disk 42 is covered by a rotatable forward nacelle 48, aerodynamically profiled to facilitate airflow through the plurality of fan blades 40. Additionally, exemplary fan section 14 includes an annular fan shroud or outer nacelle 50 circumferentially surrounding at least a portion of the fan 38 and / or the core turbine engine 16. It should be appreciated that the nacelle 50 may be configured to be supported relative to the core turbine engine 16 by a plurality of circumferentially spaced outlet guide vanes 52. Furthermore, a downstream section 54 of the nacelle 50 may extend externally over the core turbine engine 16 to define a bypass airflow passage 56 therebetween.

[0114] During operation of the turbofan engine 10, a volume of air 58 enters the turbofan through the nacelle 50 and / or the associated inlet 60 of the fan section 14. As the volume of air 58 passes over the fan blades 40, a first portion of the air 58, as indicated by arrow 62, is directed or delivered to the bypass airflow passage 56, and a second portion of the air 58, as indicated by arrow 64, is directed or delivered to the LP compressor 22. The ratio between the first portion 62 and the second portion 64 of air is generally known as the bypass ratio. The second portion 64 of air then increases in pressure as it is delivered through the high-pressure (HP) compressor 24 and into the combustion section 26, where it mixes with fuel and burns to provide combustion gases 66.

[0115] Combustion gas 66 is conveyed through an HP turbine 28, where a portion of its thermal and / or kinetic energy is extracted via a series of stages of HP turbine stator guide vanes 68 connected to the housing 18 and HP turbine rotor blades 70 connected to the HP shaft or reel 34, thereby rotating the HP shaft or reel 34 to support the operation of the HP compressor 24. Combustion gas 66 is then conveyed through an LP turbine 30, where a second portion of its thermal and kinetic energy is extracted via a series of stages of LP turbine stator guide vanes 72 connected to the housing 18 and LP turbine rotor blades 74 connected to the LP shaft or reel 36, thus rotating the LP shaft or reel 36 to support the operation of the LP compressor 22 and / or the rotation of the fan 38.

[0116] Combustion gas 66 is then delivered through the jet exhaust nozzle section 32 of the core turbine engine 16 to provide propulsive thrust. Simultaneously, the pressure of the first portion of air 62 is substantially increased because it is delivered through the bypass airflow passage 56 before exiting from the fan nozzle exhaust section 76 of the turbofan 10, also providing propulsive thrust. The HP turbine 28, LP turbine 30, and jet exhaust nozzle section 32 at least partially define a hot gas path 78 for delivering combustion gas 66 through the core turbine engine 16.

[0117] In some embodiments, components of the turbofan engine 10, particularly the hot gas passage 78 or components defining the hot gas passage 78, may include composite materials, such as ceramic matrix composites (CMC) materials with high-temperature capabilities. Composite materials typically include fiber reinforcement embedded in a matrix material, such as a ceramic matrix material. The reinforcement serves as the load-bearing component of the composite material, while the matrix of the composite material serves to bind the fibers together and act as a medium through which externally applied stress is transmitted and distributed to the fibers.

[0118] Exemplary CMC materials may include silicon carbide (SiC), silicon, silica, or alumina matrix materials, and combinations thereof. Ceramic fibers may be embedded within the matrix, such as oxidation-stabilized reinforcing fibers comprising monofilaments of sapphire and silicon carbide (e.g., Textron's SCS-6), as well as rovings and yarns comprising silicon carbide (e.g., Nippon Carbon's NICALON®, Ube Industry's TYRANNO®, and Dow Corning's SYLRAMIC®), alumina silicates (e.g., Nextel's 440 and 480), and shredded whiskers and fibers (e.g., Nextel's 440 and SAFFIL®), and optionally ceramic particles (e.g., silicon, aluminum, zirconium, yttrium, and combinations thereof) and inorganic fillers (e.g., pyrophyllite, wollastonite, mica, talc, kyanite, and montmorillonite). For example, in some embodiments, fiber bundles may include a ceramic refractory coating formed as reinforcing bands, such as unidirectional reinforcing bands. Multiple strips can be stacked together (e.g., as laminates) to form a preform component. The fiber bundles can be impregnated with a slurry composition before or after preform formation. The preform can then undergo heat treatment, such as curing or burn-out, to produce a high coke residue in the preform, and subsequent chemical treatment, such as silicon melt infiltration, to achieve a component formed from a CMC material having the desired chemical composition. In other embodiments, the CMC material can be formed, for example, as carbon fiber cloth instead of strips.

[0119] As described, components including composite materials can be used within the hot gas path 78, such as within the combustion and / or turbine section of engine 10. As an example, one or more stages of turbine rotor blades and / or turbine nozzles can be CMC components formed of CMC material. However, composite components made of CMC or other composite materials can also be used in other sections, such as the compressor and / or fan sections.

[0120] Go to Figure 2A and 2BA schematic cross-sectional view of a fairing assembly 100 according to an exemplary embodiment of this subject is provided. Figure 3 A perspective view of the fairing assembly 100 is provided. Figure 4 An exploded perspective view of the inner band 102 and outer band 104 of the fairing assembly 100 is provided, and Figure 5 A perspective view of the fairing 106 of the fairing assembly 100 is provided. The fairing assembly 100 includes an inner belt 102, an outer belt 104 surrounding the inner belt 102, and a plurality of guide vanes or fairings 106 extending between the inner belt 102 and the outer belt 104. At least a portion of the fairing 106 is hollow and surrounds or encloses a plurality of struts 108, which are part of a turbine frame and include an inner support structure 140, such as an inner hub, and an outer support structure 146, such as a housing. Figure 2A and 2B As shown, the inner belt 102 and outer belt 104 also define openings therethrough, such that the strut 108 extends from the inner support structure 140 to the outer support structure 146. Conduits may pass through some of the struts 108, and other structures, such as hangers and retainers, may be included in the fairing assembly 100, for example, for attaching the fairing assembly 100 to the engine housing, etc.

[0121] The cowling assembly 100 crosses the combustion gas flow path 78 and is therefore exposed to high temperatures during operation. That is, in the depicted embodiment, the cowling assembly 100 is a turbine nozzle cowling assembly forming an annular turbine nozzle stage, such as a plurality of turbine nozzles circumferentially positioned around the axial centerline 12 of the engine 10. Therefore, each of the plurality of cowlings 106, inner belt 102, and outer belt 104 forms a liner along the hot gas path 78, protecting metal components and the like from the heat of the combustion gases 66. Furthermore, the exemplary cowling assembly 100 described herein forms a transition from the high-pressure turbine 28 to the low-pressure turbine 30, and therefore, each of the inner belt 102 and outer belt 104 is generally conical, with its circumference increasing from the front end 110 of the cowling assembly 100 to the rear end 112 of the assembly 100.

[0122] like Figure 2A-5As further shown, the inner belt 102 and outer belt 104 are annular, single-piece structures, separate from each fairing 106. That is, each of the inner belt 102, outer belt 104, and fairings 106 is formed individually, making each component a single piece. In an exemplary embodiment, the multiple fairings 106, inner belt 102, and outer belt 104 are all formed of composite materials, such as CMC materials. However, in other embodiments, the inner belt 102, outer belt 104, and fairings 106 can be manufactured from any suitable material using any suitable process or technology. For example, one or more of components 102, 104, 106 can be formed from composite laminates using processes including lamination, sub-pilling, curing, and densification of the composite; one or more of components 102, 104, 106 can be formed from suitable materials in an additive manufacturing process; and / or one or more of components 102, 104, 106 can be formed from metallic materials using processes such as casting.

[0123] along with Figure 2A-5 Any number of guide vanes or fairings 106 may be included in the fairing assembly 100. The fairings 106 may have an airfoil shape and may form an airfoil cascade. More specifically, each fairing airfoil 106 may have a concave pressure side 114 opposite a convex suction side 116, and each side 114, 116 may extend axially from a leading edge 118 to a trailing edge 120. Furthermore, each fairing 106 may have an inner end 122 radially spaced from an outer end 124. During operation, the fairings 106 shape the airflow to improve engine efficiency. Stirrups 108, which are typically not airfoil-shaped, will negatively impact airflow and are generally constructed of materials that cannot withstand flow path conditions; therefore, fairings 106 are included to form airfoils around the stirrups 108. It will be understood that, in the example shown, a portion of the fairing 106 surrounds a structural element, such as strut 108, while the remainder of the fairing 106 does not surround any structure. However, as shown, each fairing 106 may be hollow, defining a cavity 202 such that each fairing 106 has an internal cavity pressure, as described in more detail herein.

[0124] like Figure 4 As shown, the annular inner band 102 defines a plurality of inward recesses 126, and the annular outer band 104 defines a plurality of outward recesses 128. Each inward recess 126 is formed complementary to the inner end 122 of each fairing 106, and each outward recess 128 is formed complementary to the outer end 124 of each fairing 106. Furthermore, each inward recess 126 has a front end 130 and a rear end 132, and each outward recess 128 has a front end 134 and a rear end 136. Figure 2A , 2BAs shown in Figure 3, the inner end 122 of each radome 106 is received within one of a plurality of recesses 126, and the outer end 124 of each radome 106 is received within one of a plurality of recesses 128. It will be appreciated that the radome assembly 100 includes an equal number of recesses 126, recesses 128, and radomes 106, wherein one radome 106 is positioned within one recess 126 and a corresponding recess 128. Furthermore, for each radome 106, the leading edge 118 of the radome 106 is positioned at the front end 130 of the recess 126 and the front end 134 of the recess 128, where the radome 106 is received, and the trailing edge 120 of the radome 106 is positioned at the rear end 132 of the recess 126 and the rear end 136 of the recess 128. Additionally, as... Figure 5 As depicted herein, the inner end 122 of each fairing 106 may define an inner boss 123, and the outer end 124 of each fairing 106 may define an outer boss 125. Inner recesses 126 and outer recesses 128 may be shaped to complement the inner boss 123 and outer boss 125, respectively, such that the bosses 123, 125 are received in the recesses 126, 128. Furthermore, each boss 123, 125 may provide a region for receiving a seal; for example, the inner boss 123 may receive an inner seal 278 and the outer boss 125 may receive an outer seal 280, as described in more detail herein.

[0125] exist Figure 2A-4 In the exemplary embodiment shown, the inner band 102 surrounds each recess 126 such that each recess 126 is closed at its front end 130 and rear end 132. That is, the recess 126 is not open at the front end 110 or rear end 112 of the fairing assembly 100. Similarly, the outer band 104 surrounds each outer recess 128 such that each outer recess 128 is closed at its front end 134 and rear end 136, and is not open at the front end 110 or rear end 112 of the fairing assembly 100. Therefore, the illustrated fairing assembly 100 is compatible with bolted frames (separable hub, strut, and case) or similar frame designs. More specifically, Figure 2A-4 The fairing assembly 100 shown is adapted to a turbine frame, allowing a one-piece annular inner belt 102 to be mounted relative to the frame, with the fairing 106 positioned in an inner recess 126 and a one-piece annular outer belt 104 slidingly positioned such that the outer end 124 of the fairing 106 is received in an outer recess 128. The method of assembling the fairing assembly 100 will now be described in more detail.

[0126] See Figure 2AIn some embodiments, the fairing airfoil 106 may be brazed to the inner strip 102 and / or the outer strip 104. In one exemplary embodiment, each fairing 106 is brazed to the inner strip 102 at or near its inner end 122, and each fairing 106 is brazed to the outer strip 104 at or near its outer end 124. In other embodiments, the fairing 106 may be brazed only at one of the inner end 122 or the outer end 124. It will be appreciated that by brazing the fairing airfoil 106 to the inner strip 102 and / or the outer strip 104, the need for a seal between the strips 102, 104 and the fairing 106 is eliminated. Furthermore, brazing is not limited to embodiments where the strips 102, 104 and the fairing 106 are metallic, but brazing may also be used, for example, where the strips 102, 104 and the fairing 106 are CMC.

[0127] like Figure 2B and 3 As further shown, each of the inner belt 102 and outer belt 104 can be pinned to the front end 110 of the fairing assembly 100 to hold the assembly 100 in its position within the engine 10. More specifically, a plurality of radially extending inner pins 138 extend from the support structure 140 into the front portion 142 of the inner belt 102. Similarly, a plurality of radially extending outer pins 144 extend from the support structure 146 into the front portion 148 of the outer belt 104. The support structures 140, 146 may be suspensions, retainers, etc. In some embodiments, as previously described, the inner support structure 140 may be the hub of the turbine frame, and the outer support structure 146 may be the shell of the turbine frame. Figure 2B and 3 As shown, an inner pin 138 may be received within an opening 150 in an inner belt 102, and an outer pin 144 may be received within an opening 152 in an outer belt 104. In some embodiments, pins 138, 144 may be secured in the openings 150, 152 using washers or the like, such that pins 138, 144 do not extend through the respective belts 102, 104. In other embodiments, pins 138, 144 may extend through the front portions 142, 148 of the respective belts 102, 104. The use of radial pins 138, 144 allows for radial thermal expansion of, for example, the metal support structures 140, 146, while axially and tangentially constraining the fairing assembly 100. This retaining structure mitigates the stress and strain caused by thermal mismatch between the fairing assembly 100 and the support structures 140, 146, for example, where the fairing assembly 100 is formed of a composite material and the support structures 140, 146 are made of metal or metal alloy, while still holding the fairing assembly 100 in position within the engine 10.

[0128] However, in some embodiments, the fairing assembly 100 may be bolted or otherwise fastened instead of pinned at its front end 110. In certain embodiments, assembly 100 may be bolted to one or more flexible metal suspensions that bend to compensate for thermal growth of one or more metal suspensions relative to assembly 100, which may be formed of composite materials and have different coefficients of thermal expansion. In other embodiments, the fairing airfoil 106 may include features that allow the fairing 106 to be bolted to the suspensions. Other means for holding the fairing assembly 100 in its position within the engine 10 may also be used.

[0129] In addition, such as Figure 2A As shown, in embodiments where the fairing airfoil 106 is brazed to the inner strip 102 and outer strip 104, the radial inner pin 138 or radial outer pin 144 can be removed. More specifically, by brazing the fairing 106 to the strips 102, 104, the fairing assembly 100 is effectively a one-piece structure, and therefore, the assembly 100 only needs to be pinned to the inner strip 102 or outer strip 104. Although in embodiments with outer pin 144... Figure 2A As illustrated, it will be understood that in alternative embodiments, the outer pin 144 may be removed, and the inner pin 138 may be used to pin the assembly 100 at its front end 110. Additionally, either the inner pin 138 or the outer pin 144 may be removed in embodiments where the fairing airfoil 106 is otherwise attached to the inner strip 102 and outer strip 104, for example, where the fairing 106 is pinned to strips 102, 104 as described herein.

[0130] Now go to Figure 6A-8 Other exemplary embodiments of the fairing assembly 100 will be described below. Figure 6A and 6B Each provides a schematic cross-sectional view of the fairing assembly 100, and Figure 7 Provided Figure 6A Perspective view of fairing assembly 100. Figure 8 Provided Figure 6A Exploded perspective view of the inner strip 102 and inner ring 154 of the fairing assembly 100. Although not shown in Figure 6A and 6B As described in the text, it will be recognized that the fairing assembly 100 will be installed in a similar manner to... Figure 2A and 2B Within the turbine frame shown and described, although Figure 6A and 6B The turbine frame can be with Figure 1 It is constructed differently from the turbine frame described in section 2. For example, Figure 6A-8 The fairing assembly 100 depicted can be used with a two-piece turbine frame or a similar frame design, instead of as shown in the reference above. Figure 2A-5 The bolted turbine frame, etc. An exemplary two-piece frame includes a hub and strut assembly and a separable housing, but other two-piece frames may also be used.

[0131] like Figure 6A-8 As depicted, in addition to the annular one-piece inner band 102, the fairing assembly 100 may include an annular one-piece inner ring 154. More specifically, in some embodiments, each recess 126 is open at its front end 130 and closed at its rear end 132. Thus, the inner band 102 defines a plurality of recess rear segments 156. The inner ring 154 is positioned against the front edge 160 of the inner band 102 to close the front end 130 of each recess 126. Additionally, the inner ring 154 defines a plurality of recess front segments 158, and each recess front segment 158 ​​in the inner ring 154 has a corresponding recess rear segment 156 in the inner band 102. The recess front segments 158 and recess rear segments 156 are aligned such that each recess front segment 158 ​​and its corresponding recess rear segment 156 together form one of the plurality of recesses 126. Therefore, the recesses 126 are separated, each recess 126 having a front portion (i.e., the front portion 158 of the recess) defined by the inner ring 154 and a rear portion (i.e., the rear portion 156 of the recess) defined by the inner band 102.

[0132] like Figure 6A and 8 As shown, in some embodiments, the inner band 102 is truncated or shortened, and the inner ring 154 extends beyond the front portion of the fairing 106. In the depicted embodiment, a flange 162 extends from the front edge 160 of the inner band 102, and a flange 164 extends from the rear edge 166 of the inner ring 154. Each flange 162, 164 defines a plurality of holes 168, and when the inner ring 154 is positioned against the front edge 160 of the inner band 102, the holes 168 of the inner band flange 162 are aligned with the holes 168 of the inner ring flange 164. Fasteners 170, such as bolts, washers, rivets, or the like, may extend through the flanges 162, 164 within each pair of aligned holes 168 to attach or connect the inner ring 154 to the inner band 102. Figure 6A As most clearly shown, the leading edge 160 of the inner band 102 is defined axially at the rear or downstream of the leading edge 118 of the fairing 106, such that the inner ring 154 is positioned thereto abut against the inner band 102 and defines a joint at the rear or downstream of the leading edge 118 of each fairing 106.

[0133] In other embodiments, such as Figure 6BAs shown, the inner strip 102 is not truncated or shortened, and the inner ring 154 primarily serves to close the front end 130 of each recess 126. In such an embodiment, the inner ring 154 also provides additional structure for the inner strip 102, for example, to provide support for the fairing assembly 100 at its front inner end. It will be appreciated that... Figure 6B The inner ring 154 shown can therefore be similar to the outer ring 172 described herein, for example, regarding Figure 9-11 .

[0134] Furthermore, it will be recognized that, Figure 6A-8 The outer band 104 and fairing 106 of the embodiment of the fairing assembly 100 shown can be coupled with... Figure 4 and 5 The outer band 104 shown in detail is the same as the fairing. That is to say, Figure 6A-8 The fairing assembly 100 shown includes an annular, one-piece outer belt 104. Multiple fairings 106, one example of which is... Figure 5 As shown, the recess 126 defined by the inner ring 154 and the inner band 102 extends to the outer recess 128 defined by the outer band 104. Furthermore, the inner band 102 and the inner ring 154 are generally conical in shape, such as... Figure 2A-4 The inner band 102 is shown in the figure.

[0135] As in Figure 2A-5 Shown in and about Figure 2A-5 The described embodiments, Figure 6A-8 The fairing assembly can be pinned at its front end to hold the assembly 100 in position within the gas turbine engine 10. As previously described, radial pins 138, 144 allow some radial movement to compensate for different thermal growth rates in the radial direction R of components formed of different materials, while axially and tangentially (or circumferentially) constraining the fairing assembly 100. However, in some embodiments, as described above, the fairing assembly 100 may be bolted rather than pinned to, for example, a turbine frame. In a particular embodiment, the assembly 100 may be bolted to one or more flexible metal suspensions that bend to compensate for thermal growth of one or more metal suspensions relative to the assembly 100, which may be formed of a composite material and have different coefficients of thermal expansion. In other embodiments, the fairing airfoil 106 may include features that allow the fairing 106 to be bolted to the suspensions. Other means for holding the fairing assembly 100 in position within the engine 10 may also be used.

[0136] The description in this article is as follows Figure 6A-8 The fairing assembly 100 shown is compatible with two-piece frame or similar frame designs. More specifically, Figure 6A-8The fairing assembly 100 shown is adapted to a turbine frame, allowing a one-piece annular outer belt 104 to be mounted relative to the frame. The outer end 124 of the fairing 106 is positioned in an outer recess 128, and the one-piece annular inner belt 102 and inner ring 154 slide in such that the inner end 122 of the fairing 106 is received in an inner recess 126. The method of assembling the fairing assembly 100 will now be described in more detail.

[0137] Now for reference Figure 9-13 Another exemplary embodiment of the fairing assembly 100 will be described below. Figure 9 A schematic cross-sectional view of the fairing assembly 100 is provided, and Figure 10 A perspective view of the fairing assembly 100 is provided. Figure 11 An exploded perspective view of the outer band 104 and outer ring 172 of the fairing assembly 100 is provided. Figure 12 An exploded perspective view of the axially separated fairing 106 is provided, and Figure 13 A schematic cross-sectional view of the circumferentially separated fairing 106 is provided. Furthermore, although not shown in... Figure 9 As described, it will be recognized that the fairing assembly 100 will be mounted with a turbine frame, similar to the description of... Figure 2A and 2B The turbine frame shown and described, although Figure 9 The turbine frame can be with Figure 2A and 2B The turbine frame depicted in the article, and Figure 6A-8 The fairing assembly 100 differs from the turbine frame used with it. For example, Figure 9-13 The fairing assembly 100 depicted can be used with a one-piece or integral turbine frame or similar frame design, rather than as described above. Figure 2A-5 The aforementioned bolted turbine frame, etc.

[0138] like Figure 9-11 As described, the fairing assembly 100 may include an annular one-piece outer ring 172 in addition to the annular one-piece outer ring 104. More specifically, as... Figure 11 As most clearly shown, in some embodiments of the outer band 104, each outer notch 128 opens at its front end 134 and closes at its rear end 136. The outer band 104 includes a front flange 174, and an outer ring 172 is positioned radially inwardly to the inner flange 174, as... Figure 9 and 10 As shown in the diagram. The outer ring 172 extends over the open front end 134 of the outer notch 128 to close the front end 134 of each outer notch 128; the outer band 104 otherwise generally... Figure 2A-4 The outer band 104 shown is the same. The outer ring 172 can be relatively thick in the radial direction R to provide structural support at the front end 110 of the assembly 100; as shown Figure 2A-4 As shown in Figures 6 and 7, in other embodiments, the outer strip 104 is relatively thicker at the front end 110 to provide structural support to the component 100. Additionally, as... Figure 9 and 10 As shown, the same inner band 102 and inner ring 154 are used for Figure 9-12 In the embodiment of the fairing assembly 100 shown, as Figure 6A , 7 As in the embodiment of the fairing assembly 100 shown in Figure 8.

[0139] In addition, such as in Figure 2A-5 And as shown in 6-8 and about Figure 2A-5 And the embodiments described in 6-8, Figure 9-12 A fairing assembly 100 may be pinned to the front end 110 of the assembly 100 to hold the assembly 100 in position within the gas turbine engine 10. A plurality of holes 176 may be defined in the front flange 174 of the outer belt 104, and a plurality of openings 178 may be defined in the outer ring 172. The holes 176 are defined in the outer belt 104, and the openings 178 are defined in the outer ring 172, such that when the outer ring 172 is assembled with the outer belt 104, the outer belt holes 176 and the outer ring openings 178 are aligned. Outer pins 144 may be received in each pair of aligned outer belt holes 176 and outer ring openings 178 to retain the outer ring 172 relative to the outer belt 104.

[0140] Furthermore, as previously described, radial pins 138 and 144 allow for some radial movement, for example, to compensate for different rates of thermal growth in the radial direction R by means of components formed of different materials, while axially and tangentially (or circumferentially) constraining the fairing assembly 100. However, in some embodiments, as described above, the fairing assembly 100 may be bolted rather than pinned to, for example, a turbine frame. In certain embodiments, the assembly 100 may be bolted to one or more flexible metal suspensions that bend to compensate for thermal growth of one or more metal suspensions relative to the assembly 100, the assembly 100 may be formed of a composite material and have different rates of thermal expansion. In other embodiments, the fairing airfoil 106 may include features that allow the fairing 106 to be bolted to the suspensions. Other means for holding the fairing assembly 100 in a position within the engine 10 may also be used.

[0141] As described in this article, Figure 9-11 The fairing assembly 100 shown is compatible with a one-piece frame or similar frame design. More specifically, Figure 9-11 The fairing assembly 100 shown utilizes two annular members at each of its internal and external portions, allowing the assembly 100 to be mounted around a single-piece frame. Furthermore, specific reference is made to... Figure 12At least one of the plurality of fairings 106 may be axially divided into a front section 180 and a rear section 182, such that the fairing 106 may be positioned around and around one of the struts 108. That is, due to the turbine frame design, the fairings 106 must be separated for mounting around the strut 108. The front section 180 and the rear section 182 of each fairing 106 may be abutted along a first joint line 184 and a second joint line 186. More specifically, the front section 180 and the rear section 182 may each define half of a rabbet or half lap joint. The front section 180 and the rear section 182 are joined together along the first joint line 184 and the second joint line 186 to form the fairing 106. Furthermore, it will be understood that the inner band 102 and outer band 104, in which the respective ends 122, 124 of the fairing 106 are received, help to keep the front section 180 and the rear section 182 together (i.e., help to prevent the front section 180 and the rear section 182 from separating).

[0142] In other embodiments, such as Figure 13 As shown, at least one of the plurality of fairings 106 can be circumferentially divided into a first side section 188 and a second side section 190; one side section 188, 190 can correspond to the pressure side of the airfoil-shaped fairing 106, and the other side section 188, 190 can correspond to the suction side of the airfoil-shaped fairing 106. The first side section 188 and the second side section of each fairing 106 are adjacent to a first joint 192 at the leading edge 118 and a second joint 194 at the trailing edge 120. Figure 13 As shown, each of the first connector 192 and the second connector 194 is an overlapping connector. For example, the second side segment 190 overlaps with the first side segment 188 at the first connector 192, and the first side segment 188 overlaps with the second side segment 190 at the second connector. More specifically, each of the first side segment 188 and the second side segment 190 defines a notch 196 along the leading portion 118, and the first side segment 188 and the second side segment 190 engage together along the notch 196 to form an overlapping first connector 192. The first side segment 188 defines a notch 198 at a trailing edge 120, and the second side segment 190 defines a protrusion 200 that engages within the notch 198 to form an overlapping second connector 194. Furthermore, it will be appreciated that the inner strip 102 and outer strip 104, in which the respective ends 122, 124 of the fairing 106 are received, help to keep the first side section 188 and the second side section 190 together (i.e., help to prevent the first side section 188 and the second side section 190 from separating).

[0143] like Figure 5 , 12As shown in Figure 13, whether formed as a single-piece structure, axially separated, or circumferentially separated, each fairing 106 defines a cavity 202, the dimensions of which can be designed to receive struts 108 or other structural components. Fluid can be received in each fairing airfoil cavity 202 such that the internal pressure of the fairing 106 is higher than the external pressure of the fairing 106. Figure 12 and 13 In the separated fairing embodiment, higher cavity pressure helps push fairing sections 180, 182 and 188, 190 together to achieve a tight seal between these sections. Furthermore, as... Figure 13 As shown, any leakage from cavity 202 will be axially pushed toward the trailing edge 120 of fairing 106 and the second connector 194. Therefore, a seal 204, such as a spline seal, may extend along the second connector 194 between the first side section 188 and the second side section 190, for example, between the notch 198 and the protrusion 200, to help reduce leakage from high-pressure cavity 202. Other seals may also be included in... Figure 12 and 13 The shroud 106 shown is included to help reduce leakage from cavity 202.

[0144] Now go to Figure 14Each recess 126 and recess 128 can be configured to form a stop for each fairing 106. Furthermore, each of the inner strip 102 and outer strip 104 can be constructed at the rear end 112 of the fairing assembly 100 to provide an area for sealing at each of the inner strip 102 and outer strip 104. More specifically, each recess 126 includes a lip 206 extending around the recess 126, and an inner end 122 of each fairing 106 is received within the recess 126 such that the inner end 122 contacts the lip 206. Similarly, each recess 128 includes a lip 208 extending around the recess 128, and an outer end 124 of each fairing 106 is received within the recess 128 such that the outer end 124 contacts the lip 208. Therefore, the inner lip 206 acts as an inner stop for the fairing 106, and the outer lip 208 acts as an outer stop for the fairing 106, whereby the inner lip 206 and the outer lip 208 help prevent radial and / or tangential (or circumferential) slippage of the fairing 106. In some embodiments, a seal 210, such as a line seal, may extend around each of the recesses 126 and 128, for example, in the recesses 126 and 128, close to the inner belt 102 and the outer belt 104 to define the position of the lips 206, 208, such that the seal 210 can contact each of the inner end 122 and the outer end 124 of the fairing 106 to form a seal between the fairing 106 and the belts 102, 104. Because the internal pressure of the fairing 106 is greater than the external or flow path pressure, the internal pressure pushes the fairing 106 into the seal 210, which helps to improve the effectiveness of the seal 210, that is, to form a good seal between the fairing 106 and the belts 102, 104. Figure 12 and 13 The separation fairing 106 shown can have a particularly good seal between the fairing 106 and the bands 102, 104 when the higher internal pressure of the fairing 106 pushes the sections 180, 182 or 188, 190 into the seals 210 and the bands 102, 104.

[0145] Additionally, the rear edge 212 of the inner belt 102 may be constructed, for example, thicker than the rest of the inner belt 102, to define the inner surface 214. Similarly, the rear edge 216 of the outer belt 104 may be constructed, for example, thicker than the rest of the outer belt 104, to define the outer surface 218. Each of the inner surface 214 and the outer surface 218 may provide a surface against which a seal, such as a piston annular seal, may be positioned such that the fairing assembly 100 seals at its rear end 112 along each of the inner belt 102 and the outer belt 104.

[0146] Figure 15 , 16Figures 106 and 17 provide radial cross-sectional views of a portion of a fairing end and a strip notch according to various exemplary embodiments of the subject matter, wherein a seal is positioned therebetween, for example, to provide a seal and abrasion protection between fairing 106 and the corresponding strips 102, 104. See in particular... Figure 15 According to an exemplary embodiment of this subject matter, a radial cross-sectional view is provided of the outer end 124 of the fairing 106 and a portion of the outer notch 128 of the outer strip 104. As... Figure 15 As shown, a seal 220 can be positioned between the outer end 124 of the fairing 106 and the outer recess 128 of the outer belt 104. More specifically, the seal 220 includes a wear portion 222 extending along a radial surface 224 of the outer recess 128. A retainer portion 226 extends from the wear portion 222 of the seal 220 into the outer belt 104, for example, to retain the seal 220 in a position within the outer recess 128. The retainer portion 226 may extend around the entire periphery of the seal 220, or the seal 220 may define a plurality of retainer portions 226 spaced apart from each other, such that the retainer portions 226 are received within the outer recess 128 at various locations around the outer recess 128.

[0147] Furthermore, the wear portion 222 of the seal 220 defines a planar wear surface 228 against which the outer end 124 of the fairing 106 can be positioned. That is, the wear surface 228 of the seal 220 is located between the outer end 124 of the fairing 106 and the outer band 104, allowing the fairing 106 to rub or slide against or otherwise contact the seal 220 instead of the outer band 102, thus helping to prevent wear between the fairing 106 and the outer band 104 in the region of the recess 128. Additionally, the seal 220 includes a seal arm 230 compressed between the outer end 124 of the fairing 106 and the outer band 104. More specifically, the seal arm 230 extends between the lip 208 of the recess 128 and the radially outermost surface 232 of the fairing 106. The seal arm 230 is curved, giving it a generally serpentine or S-shaped cross-section. Figure 15 In the exemplary embodiment shown, the seal arm 230 protrudes from the wear portion 222 to contact the outer notch lip 208, and then bends toward the surface 232 of the fairing 106 until the seal arm 230 contacts the surface 232. Thus, the seal 220 is configured to allow radial thermal growth for the outer belt 102, the fairing 106, the seal 220, and / or components surrounding and / or supporting the fairing assembly 100, while also providing a seal and wear protection between the fairing 106 and the outer notch 128.

[0148] It will be appreciated that a plurality of seals 220 may be provided for the fairing assembly 100. One of the seals 220 may extend within each outer recess 128 such that the seal 220 is received within the outer recess 128 between the outer recess 128 and the outer end 124 of the fairing 106. Furthermore, the seal 220 may also be used between the inner end 122 and the inner recess 126 of the fairing 106. In such an embodiment, the inner fairing end 122, the inner recess 126, and the seal 220 may be as follows: Figure 15 The structure shown depicts a sealing arm 230 extending radially outward from the seal 220 rather than radially inward; that is, when used as an inner seal 220, the seal 220 will... Figure 15 The view provided can be flipped or rotated around the circumferential direction C.

[0149] Go to Figure 16 According to another exemplary embodiment of this subject matter, a radial cross-sectional view of the outer end 124 of the fairing 106 and a portion of the outer notch 128 of the outer strip 104 is provided. Figure 16 As shown, a seal 234 can be positioned between the outer end 124 of the fairing 106 and the outer recess 128 of the outer band 104. More specifically, the seal 234 defines a channel 236 into which the outer end 124 of the fairing 106 is received, such that the seal 234 is clamped onto or otherwise attached to the outer end 124 of the fairing. In the depicted embodiment, the outer end 124 of the fairing is cut along an inner surface 238 and an outer surface 240, and the seal 234 includes a protrusion 242 received in a notch 244 to attach the seal 234 to the outer end 124 of the fairing. Furthermore, the seal 234 includes a wear portion 246 defining a planar wear surface 248 that can be positioned against the outer recess 128. In other words, the wear surface 248 of the seal 234 is between the outer end 124 of the fairing 106 and the outer belt 104, such that the seal 234 can rub or slide against (or otherwise contact) the outer belt 104, rather than the fairing 106 contacting the outer belt 104, thereby helping to prevent wear between the fairing 106 and the outer belt 104 in the area of ​​the recess 128.

[0150] In addition, with Figure 15 The seal 220 shown is identical to the one described above. Seal 234 includes a seal arm 250, which is compressed between the outer end 124 of the fairing 106 and the outer band 104. More specifically, the seal arm 250 extends between the radially outermost surface 232 of the fairing 106 and the lip 208 of the outer notch 128. The seal arm 250 is bent such that it has a generally C-shaped or U-shaped cross-section. Figure 16In the exemplary embodiment shown, the seal arm 250 protrudes from the sealing channel 236 and bends toward the recessed lip 208 until the seal arm 250 contacts the lip 208. Therefore, the seal 234 is configured to allow radial thermal growth of the outer band 102, the fairing 106, the seal 234, and / or the components surrounding and / or supporting the fairing assembly 100, while also providing a seal and abrasion protection between the fairing 106 and the recess 128.

[0151] It will be understood that a plurality of seals 234 may be provided for the fairing assembly 100. One of the seals 234 may extend around the outer end 124 of each fairing 106, such that the seal 234 is received within the outer recess 128 between the outer recess 128 and the outer end 124 of the fairing 106. Furthermore, the seal 234 may also be used between the inner end 122 and the inner recess 126 of the fairing 106. In such an embodiment, the inner fairing end 122, the inner recess 126, and the seal 234 may be as follows: Figure 16 The structure shown depicts a sealing arm 250 extending radially inward toward the inner lip 206, rather than radially outward toward the outer lip 208. This means that when used as an inner seal 234, the seal 234 extends from... Figure 16 The view provided will be flipped or rotated around the circumferential direction C.

[0152] See Figure 17 A radial cross-sectional view is provided of the outer end 124 of the fairing 106 and a portion of the outer recess 128 of the outer belt 104, illustrating another exemplary embodiment of the seal between the fairing 106 and the outer belt 104. Figure 17 As shown, the seal 252 may be clipped onto the outer lip 208 or otherwise attached to the outer lip 208 instead of as shown. Figure 16 The outer end 124 of the fairing shown is such that the seal 252 is positioned between the outer end 124 of the fairing and the outer recess 128 of the outer belt 104. More specifically, the seal 252 defines a channel 254 into which the lip 208 of the outer recess 128 is received. Arms 256 of the channel 254 extend along each of the inner surface 258 and the outer surface 260 of the lip 208. Furthermore, the inner arm 256 of the seal 252 serves as a wear portion of the seal 252, defining a planar wear surface 262 that can be positioned against the outermost surface 232 of the fairing 106. In other words, the wear surface 262 of the seal 252 is between the outer end 124 of the fairing 106 and the outer belt 104, so that the fairing 106 can rub or slide against (or otherwise contact) the seal 252 instead of the outer belt 104, thereby helping to prevent wear between the fairing 106 and the outer belt 104 in the area of ​​the recess 128.

[0153] In addition, such as Figure 15 and 16 The seals 220 and 234 shown, seal 252 includes a seal arm 264 compressed between the outer end 124 of the fairing 106 and the outer band 104. More specifically, the seal arm 264 extends between the radial surface 224 of the outer recess 128 and the sides 114, 116 of the fairing 106. The radial surface 225 may define a recess 225 such that the seal arm 264 extends radially within the recess 225. Furthermore, the seal arm 264 is curved, giving it a generally C-shaped or U-shaped cross-section. Figure 17 In the exemplary embodiment shown, the seal arm 264 protrudes from the inner channel arm 256 along the radial surface 224 and bends toward the outer end 124 of the fairing until the seal arm 264 contacts the sides 114, 116 of the fairing 106; it will be appreciated that the seal 252 and the seal arm 264 extend around the outer end 124 of the fairing such that a portion of the seal arm 264 contacts the pressure side 114 and the remainder contacts the suction side 116. Therefore, the seal 234 is configured to allow axial and circumferential thermal growth of the outer band 102, the fairing 106, the seal 52, and / or the components surrounding and / or supporting the fairing assembly 100, while also providing a seal and abrasion protection between the fairing 106 and the outer notch 128.

[0154] It will be understood that a plurality of seals 252 may be provided for the fairing assembly 100. One of the seals 252 may extend around the lip 208 of each recess 128, such that the seal 252 is received within the recess 128 between the recess 128 and the outer end 124 of the fairing 106. Furthermore, the seal 252 may also be used between the inner end 122 of the fairing 106 and the inner recess 126. In such an embodiment, the inner fairing end 122, the inner recess 126, and the seal 252 may substantially be as follows: Figure 17 Constructed as shown in the diagram.

[0155] Now go to Figure 18A , 18B Articles 1 and 19 will describe features for pinning the fairing airfoil 106 into the fairing assembly 100. (See also:) Figure 18A and 18B As shown, a pin 266 with a retaining member 268 can be inserted into a hole 270 in each fairing 106. More specifically, the first end 270 of the pin 266 can be inserted into a hole 272 on the sides 114, 116 of each fairing 106. In embodiments where the fairing 106 is divided into a front section 180 and a rear section 182, the pin 266 can help hold the sections 180, 182 together, as... Figure 18B As shown in the image. Reference Figure 19An aperture 272 may be defined in the inner end 122 of each fairing 106, such that a pin 266 pins the fairing 106 to the inner belt 102. The inner belt 102 defines a recess 274 in which the second end 276 of each pin 266 is received. Figure 19 As shown, the pin-fitted fairing 106 is optimally suited for use with a fairing assembly 100 utilizing an inner belt 102 and an inner ring 154, for example, as per [reference to...]. Figure 6A-10 As described above. In such an embodiment, the inner ring 102 can be positioned within the engine 10, and then a fairing 106 with a pin 266 in an insertion hole 272 can be installed such that the inner end 122 of the fairing is received in the rear section 156 of the recess, and the second end 276 of the pin is received in the groove 274. The inner ring 154 can then be manipulated into place to surround the inner end 122 of the fairing in the recess 126 (its front section 158 is defined by the inner ring 154) and close the groove 274, such that the second end 276 of the pin is retained in the groove 274. The retaining member 268 helps to retain the pin 266 in the hole 272 and minimizes the circumferential movement of the pin 266.

[0156] In an alternative embodiment, the groove 274 may be defined in the inner ring 154 instead of the inner band 102 (the assembly method may be modified as needed to properly assemble this configuration), such that the second end 276 of the pin is received in the inner ring 154 instead of the inner band 102. In yet another embodiment, the groove 274 may be partially defined by the inner band 102 and partially by the inner ring 154, such that the second end 276 of the pin is secured between the inner band 102 and the inner ring 154. Furthermore, in some embodiments, the fairing 106 may be pinned at the outer end 124 instead of the inner end 122, wherein the hole 272 is defined in the outer end 124 of the fairing and the groove 274 (or, if appropriate, the hole for receiving the second end 276 of the pin) is defined in the outer band 104.

[0157] like Figure 19 As further shown, the seal may extend around each of the inner end 122 and outer end 124 of the fairing 106. In some embodiments, the inner seal 278 may be a line seal, etc., having a circular cross-sectional shape, and the outer seal 280 may be a piston seal, etc., having a square cross-sectional shape. The square cross-sectional seal 280 may be adapted to a planar geometry and may be present at the outer end 124, while the circular cross-sectional seal 278 may be adapted to a more complex geometry and may be present at the inner end 122. Of course, any suitable seal may be used, including those related to… Figure 15-17 The exemplary seals described are 220, 234, and 252.

[0158] Figure 20AReferences 20B and 21-24 provide schematic cross-sectional views of various gasket and fastener configurations according to exemplary embodiments of this subject matter. For example, these gasket and fastener configurations can be used to secure portions of the cowling assembly 100 to each other within the engine 10, etc. See also... Figure 20A and 20B This provides a washer construction that can be used in blind or non-through holes, for example, for lining holes, and thereby protects the component defining the hole. More specifically, the non-through hole 282 can be defined in a component, for example, as... Figure 2A and 2B The front portion 148 of the outer strip 104 shown, and the hole 282 can be machined such that it gradually tapers outward along its side 284 near its closed distal end 286. That is, as Figure 20A As shown, the cross-section of the hole 282 is larger near its closed distal end 286 than near its open proximal end 288. A washer 290 with an angled end 292 is inserted into the hole 282, wherein the angled end 292 is angled inward, i.e., toward the axial centerline 294 of the washer 290. A tool 296 can be inserted into the washer 290 to push the angled end 292 outward, as shown. Figure 20B As shown, the angled end 292 unfolds or angles outward and engages within the tapered portion of the hole 282, i.e., the distal end 286, after the insertion of the tool 296. It will be appreciated that, in other embodiments, the angled washer 290 may be used to hold two components together rather than merely lining the hole 282, for example, to protect the component defining the hole 282. Furthermore, instead of using the tool 296 to push or unfold the angled end 292 of the washer 290, fasteners such as screws, bolts, pins, etc., may be inserted into the washer 290 to push or unfold the angled end 292 of the washer.

[0159] Go to Figure 21 and 22 In some embodiments, multiple washers and pins can be used to secure two components to each other. For example... Figure 21 As shown, washer 298 can be inserted and secured into a non-through hole 282 in the first component 300, and forged washer 302 can be attached to an opening 304 in the second component 306; the second component 306 is coupled to the first component 300. A pin 308 having a head 310 is inserted into an opening 312 defined by washers 298 and 302, and pin 308 can be welded to forged washer 302. Figure 22As shown, instead of inserting the washer 298 into a non-through hole such as hole 282, the washer 298 can be secured in the through hole 314. Furthermore, the headless pin 316 can be used to connect the first component 300 and the second component 306, and the washer 298 may include a bottom portion 318 to prevent the pin 316 from sliding through the opening 312 defined by the washers 268, 302. Additionally, the pin 316 can be welded to the washer 302 to secure the pin 316 in place.

[0160] Now for reference Figure 23 An extended insert or washer 320 can be used in the first component 300. More specifically, the washer 320 extends outward at its distal end 322 such that the distal end 322 has a larger cross-section than the body 324 of the washer 320, and the hole 282 or 314 in which the washer 320 is received is also extended or angled to receive the distal end 322 of the washer. The washer 320 may include an anti-rotation feature 326, such as a collar or similar, disposed in the first component 300 at the proximal end 328 of the washer 320 to prevent the washer 320 from rotating within the hole 282 or 314 in which the washer 320 is secured. A fastener 330, such as a pin or bolt, can be inserted through the second component 306 and into the washer 320 to secure the first component 300 and the second component 306 together. In addition, a washer 332 can be used, for example, to prevent wear between fastener 330 and second component 306.

[0161] Figure 24 Another embodiment of a washer and fastener construction for securing two components to each other is shown. Figure 24 In one embodiment, the washer 320 extends within both the first component 300 and the second component 306. For example... Figure 23 As shown, the washer 320 includes an extended distal end 322 received within an extended aperture 282 or 314 in the first component 300. The body 324 of the washer 320 extends through the second component 306, and the proximal end 328 may be forged around the fastener 330 to retain the fastener within the washer 320. In other embodiments, the fastener 330 may be welded to the washer 320, either in addition to or as an alternative to forging the proximal end 328 of the washer.

[0162] Figure 25A flowchart illustrating a method 2500 for assembling a cowling assembly 100 in a gas turbine engine, such as a turbofan engine 10, according to an exemplary embodiment of this subject matter is provided. Method 2500 includes installing an annular one-piece inner belt 102 in the gas turbine engine, as shown at 2510. The inner belt 102 defines a plurality of recesses 126 as described herein, and method 2500 includes, as shown at 2520, inserting an inner end 122 of each of a plurality of cowlings 106 into a recess 126 among the plurality of recesses 126. Next, as shown at 2530, method 2500 includes sliding an annular one-piece outer belt 104 in place relative to the plurality of cowlings 106 such that an outer end 124 of each of the plurality of cowlings 106 is received in a recess 128 among a plurality of recesses 128 defined by the outer belt 104. In an exemplary embodiment, the outer strap 104 is slidably positioned from the front end 110 of the fairing assembly 100 toward the rear end 112 of the assembly 100. Optionally, method 2500 may further include securing the fairing 106 to one or both of the inner strap 102 and the outer strap 104 via pins, bolts, brazing, connections, or any other suitable attachment means. For example, once the outer strap 104 is in position relative to the fairing 106, the fairing 106 may be secured to the inner strap 102 and / or the outer strap 104.

[0163] Method 2500 can be used to assemble fairing assembly 100, as per [reference to...] Figure 2A-5 The turbine frame described herein has a bolted frame design, although method 2500 can also be used with other frame designs. In embodiments where the fairing assembly is used with a bolted turbine frame, method 2500 may further include mounting a strut 108 through the inner belt 102, outer belt 104, and fairing 106 of the fairing assembly 100, as shown at 2540, although the strut 108 does not need to extend through each fairing 106. Next, as shown at 2550 and 2560, the strut 108 is secured to the inner hub 140 and the outer shell 146, for example, by bolting the strut 108 to the hub 140 and the shell 146. Figure 2A As depicted herein, the fairing assembly 100 can be pinned to the outside of its front end 110, and therefore, method 2500 includes inserting at least one pin 144 at 2570 through the housing 146 and into an opening 152 in the outer band 104. The opening 152 may be a blind hole as described herein. Method 2500 may also include a step for securing the pin 144 relative to the fairing assembly 100. Furthermore, as... Figure 2B As shown, the fairing assembly 100 may also be pinned to the inside of its front end 110, such that method 2500 includes inserting at 2570 at least one pin 138 through the inner hub 140 and into the opening 150 in the inner belt 102 to pin the fairing assembly 100 to its inside and outside.

[0164] Other exemplary assembly methods are also provided. Figure 26 A flowchart illustrating a method 2600 for assembling a cowling assembly 100 in a gas turbine engine, such as a turbofan engine 10, according to another exemplary embodiment of this subject matter is provided. As shown at 2610, method 2600 includes mounting one of a plurality of cowlings 106 above each strut 108 of a turbine frame. Method 2600 then includes mounting an annular one-piece outer belt 104 in the gas turbine engine, as shown at 2620. The outer belt 104 defines a plurality of outer notches 128 as described herein, and method 2600 includes, as shown at 2630, inserting the outer end 124 of each of the plurality of cowlings 106 into the outer notch 128 of the plurality of outer notches 128. Next, as shown at 2640, method 2600 includes sliding an annular one-piece inner strip 102 relative to a plurality of fairings 106 such that the inner end 122 of each of the plurality of fairings 106 is received in a recessed rear section 156 of a plurality of recessed rear sections 156 defined by the inner strip 102.

[0165] Then, as shown at 2650, method 2600 includes positioning an inner ring 154 at the leading edge 160 of the inner band 102. As described herein, the two-piece inner band 102 and inner ring 154 of the fairing assembly 100 allow the fairing assembly 100 to be mounted around the turbine frame. The recessed rear section 156 of the inner band 102 forms an open recess 126, i.e., a recess that opens at a front end 130 and closes at a rear end 132, and the inner ring 154 is positioned at the leading edge 160 of the inner band 102 to close the front end 130. As described herein, the inner ring 154 defines a plurality of recessed front sections 158, and the recessed front sections 158 and the recessed rear sections 156 together define inner ends 122 surrounding the plurality of fairings 106. Method 2600 may further include, as shown at 2660, engaging the inner ring 154 to the inner belt 102, for example, by fastening the inner ring flange 164 to the inner belt flange 162 using suitable fasteners 170. Optionally, method 2600 may further include securing the fairing 106 to one or both of the inner belt 102 and the outer belt 104 via pins, bolts, brazing, connections, or any other suitable attachment means. For example, once the inner belt 102 is in position relative to the fairing 106, the fairing 106 may be secured to the inner belt 102 and / or the outer belt 104. Method 2600 can be used to assemble the fairing assembly 100, as per [reference to...]. Figure 6A-8 The turbine frame has a two-piece frame design, but method 2600 can also be used with other frame designs.

[0166] Figure 27A flowchart is provided illustrating a method 2700 for assembling a cowling assembly 100 in a gas turbine engine, such as a turbofan engine 10, according to yet another exemplary embodiment of this subject matter. Method 2700 can be used to assemble the cowling assembly 100, as per [reference to...]. Figure 9-13 As described, the turbine frame has a single or monolithic frame design, although method 2700 can also be used with other frame designs. Therefore, method 2700 includes mounting an inner belt 102, an outer belt 104, and a fairing 106 around the turbine frame. Thus, an open inner recess 126 and an outer recess 128 can be used, with an inner ring 154 and an outer ring 172 therein to close the inner recess 126 and the outer recess 128.

[0167] Reference Figure 27 As shown at 2710, method 2700 includes mounting an annular one-piece outer belt 104 in a gas turbine engine. The outer belt 104 defines a plurality of external notches 128 as described herein. Next, as shown at 2720, method 2700 includes positioning an outer ring 172 at the front flange 174 of the outer belt 104, as shown at 2720, and engaging the outer ring 172 to the outer belt 104, as depicted at 2730. Thus, the two-piece outer belt 104 and outer ring 172 of the outer portion of the cowling assembly 100 are mounted around the turbine frame.

[0168] Then, as shown at 2740, multiple first fairing sections can be assembled with multiple second fairing sections to form multiple fairings 106. (See also: Regarding...) Figure 12 and 13 The first and second fairing sections can be a front section 180 and a rear section 182 of a separate fairing 106, or a first side section 188 and a second side section 190. The fairing 106 is separated such that it can be mounted around the strut 108 and / or other components of the monolithic turbine frame. After assembling the first and segmental fairing sections to form the fairing 106, each fairing 106 slides into an external recess 128 defined in the outer band 104, as shown at 2750.

[0169] Method 2700 further includes sliding an annular one-piece inner belt 102 relative to the assembled fairing 106, as shown at 2760. The inner belt 102 defines a plurality of recesses 126. Next, method 2700 includes positioning an inner ring 154 at the leading edge 160 of the inner belt 102, as shown at 2770, and engaging or securing the inner ring 154 to the inner belt 102, as shown at 2780. Thus, the two-piece inner belt 102 and inner ring 154, internally separated within the fairing assembly 100, are mounted around the turbine frame. As described herein, the inner ring 154 closes the recesses 126, and the outer ring 172 closes the outer recesses 128. The inner ring 154 can be secured to the inner belt 102 using any suitable fastener, and the outer ring 172 can be engaged to the outer belt 104, for example, by pinning the outer ring 172 to the outer belt 104. Optionally, method 2700 may also include securing the fairing 106 to one or both of the inner belt 102 and the outer belt 104 via pins, bolts, brazing, bonding, or any other suitable attachment means. For example, once the inner belt 102 is in position relative to the fairing 106, the fairing 106 may be secured to the inner belt 102 and / or the outer belt 104.

[0170] Furthermore, as described herein, the inner band 102, outer band 104, and fairing 106 can be formed from CMC material. It will be appreciated that the inner ring 154 and outer ring 172 can also be formed from CMC or other suitable composite materials, and the separate fairing 106 can be formed from CMC or other composite materials. However, the inner band 102, outer band 104, fairing 106, inner ring 154, and / or outer ring 172 can also be formed from any suitable material. The specific processing techniques and parameters used to form the components of the fairing assembly 100 will depend on the specific composition of the material. For example, silicon CMC components can be formed from fibrous materials infiltrated with molten silicon, for example, through a process commonly known as the Silcomp process. Another technique for manufacturing CMC components is the slurry casting melt infiltration (MI) process. Other techniques for forming CMC components include polymer infiltration and pyrolysis (PIP) and oxide / oxide processes. Components can also be made from carbon fiber reinforced silicon carbide matrix (C / SiC) CMC, which is treated using chemical vapor infiltration.

[0171] Furthermore, in some embodiments, one or more components of the fairing assembly 100 may be formed using suitable additive manufacturing techniques or processes, such as fused deposition modeling (FDM), selective laser sintering (SLS), 3D printing such as inkjet and laser printing, stereolithography (SLA), direct selective laser sintering (DSLS), electron beam sintering (EBS), electron beam melting (EBM), laser engineered net-shape (LENS), laser net-shape manufacturing (LNSM), direct metal deposition (DMD), digital light processing (DLP), direct selective laser melting (DSLM), selective laser melting (SLM), direct metal laser melting (DMLM), and other known processes. In addition to direct metal laser sintering (DMLS) or direct metal laser melting (DMLM) processes where an energy source is used to selectively sinter or melt portions of the powder layer, it should be recognized that, according to alternative embodiments, the additive manufacturing process may be a “binder jetting” process. In this respect, binder jetting involves the continuous deposition of additive powder layers in a manner similar to DMLS or DMLM processes. However, instead of using an energy source to generate an energy beam to selectively melt or molten the additive powder, binder jetting involves selectively depositing a liquid binder onto each layer of powder. For example, the liquid binder could be a photocurable polymer or another liquid binder. Other suitable additive manufacturing methods and variations are intended to fall within the scope of this subject matter.

[0172] The additive manufacturing process described herein can be used to form parts using any suitable material. For example, the material can be plastic, metal, concrete, ceramic, polymer, epoxy resin, photopolymer resin, or any other suitable material, which can be solid, liquid, powder, sheet material, wire, or any other suitable form. More specifically, according to exemplary embodiments of the subject matter of the invention, the additively manufactured parts described herein can be formed partially, integrally, or in some combination of materials, including but not limited to pure metals, nickel alloys, chromium alloys, titanium, titanium alloys, magnesium, magnesium alloys, aluminum, aluminum alloys, iron, ferroalloys, stainless steel, and nickel-based or cobalt-based superalloys (e.g., those under the name Inconel® available from Special Metals Corporation). These materials are examples of materials suitable for the additive manufacturing process described herein and are generally referred to as "additive materials".

[0173] Furthermore, the additive manufacturing processes disclosed herein allow a single component to be formed from multiple materials. Therefore, the components described herein can be formed from any suitable mixture of the aforementioned materials. For example, a component may comprise multiple layers, segments, or parts formed using different materials, processes, and / or on different additive manufacturing machines. In this way, components with different materials and material properties can be constructed to meet the requirements of any particular application. Moreover, although the components described herein can be constructed entirely by additive manufacturing processes, it should be recognized that, in alternative embodiments, all or part of these components may be formed via casting, machining, CMC component processes as described herein, and / or any other suitable manufacturing process. In fact, any suitable combination of materials and manufacturing methods can be used to form these components.

[0174] Therefore, the above embodiments offer a variety of benefits. For example, embodiments of the fairing assembly described herein utilize a one-piece inner and outer belt, which reduces leakage and pressure loss, as well as the number of parts, manufacturing complexity, and manufacturing cost. Furthermore, the separate fairing assembly described herein is suitable for use with a wide variety of turbine frame constructions, including one-piece frames. The ability to use a one-piece turbine frame allows for reduced frame weight and lower frame costs. Additionally, the fairing assembly embodiments described herein can be formed from CMC materials, which offer reduced weight and increased thermal resistance compared to other fairing assemblies. Furthermore, separating the fairing airfoil from the belt allows for relative thermal expansion, which reduces thermal stress in the fairing assembly and allows for a more defect-resistant design. Therefore, the above embodiments offer commercial advantages, such as reduced frame aerodynamic losses and manufacturing costs, and allow for improved operating temperatures and efficiency. Other advantages of the subject matter described herein can also be realized by those skilled in the art.

[0175] This written description uses examples to disclose the invention, including the best mode, and also enables any person skilled in the art to practice the invention, including making and using any device or system, and performing any combination of methods. The patentable scope of the invention is defined by the claims and may include other examples that would occur to a person skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that are not different from the literal language of the claims, or if they include equivalent structural elements that are not substantially different from the literal language of the claims.

Claims

1. A cowling assembly for a gas turbine engine, the cowling assembly comprising: Multiple fairings, each fairing having an inner end radially spaced from an outer end, each fairing extending axially from a leading edge to a trailing edge; An annular inner band defines multiple recesses, each recess being complementary to the inner end of each fairing, and each recess having a front end and a rear end. An annular outer band defines multiple outward notches, each notch complementary to the outer end of each fairing, and each notch has a front end and a rear end. A pin, extending radially through the annular outer band, is configured to allow the annular outer band to expand radially. The annular inner band is a single-piece, integral structure that extends 360° around the axial centerline. The annular outer band is a single-piece, integral structure that extends 360° around the axial centerline, and The inner end of each fairing is received in an inner recess among multiple inner recesses, and the outer end of each fairing is received in an outer recess among multiple outer recesses.

2. The fairing assembly of claim 1, wherein the annular inner band surrounds each recess such that each recess is closed at the front end and the rear end.

3. The fairing assembly of claim 1, wherein the annular outer band surrounds each outer notch such that each outer notch is closed at the front end and the rear end.

4. The fairing assembly according to claim 1, wherein, Each recess is open at the front end and closed at the rear end.

5. The fairing assembly according to claim 4, further comprising: The inner ring is positioned against the front edge of the inner ring band to close the front end of each recess.

6. The fairing assembly according to claim 4, wherein, Each notch is open at the front end and closed at the rear end.

7. The fairing assembly according to claim 6, further comprising: The outer ring is positioned at the front flange of the outer ring to close the front end of each outer notch.

8. The fairing assembly of claim 1, wherein the plurality of fairings, the inner annular band, and the outer annular band are each formed of a ceramic matrix composite material.

9. A cowling assembly for a gas turbine engine, the cowling assembly comprising: Multiple fairings, each fairing having an inner end radially spaced from an outer end, each fairing extending axially from a leading edge to a trailing edge; An inner ring, which includes a flange extending from a rear edge, defines a plurality of recessed front sections; An annular inner band includes a flange extending from a front edge, the annular inner band defining a plurality of recessed rear sections, the flange of the inner ring being positioned against the flange of the annular inner band such that the recessed front section and the recessed rear section form a plurality of recesses, each recess being complementary to the inner end of each fairing, each recess having a front end and a rear end. Fasteners that extend through the flange of the inner ring and the flange of the annular inner band to connect the inner ring to the annular inner band; and An annular outer band defines multiple outward notches, each notch complementary to the outer end of each fairing, and each notch has a front end and a rear end. The inner ring is a single-piece, integral structure that extends 360° around the axial centerline. The annular inner band is a single-piece, integral structure that extends 360° around the axial centerline. The annular outer band is a single-piece, integral structure that extends 360° around the axial centerline, and The inner end of each fairing is received in an inner recess among multiple inner recesses, and the outer end of each fairing is received in an outer recess among multiple outer recesses.

10. The fairing assembly according to claim 9, further comprising: Outer ring road The outer ring is a single-piece, integral structure that extends 360° around the axial centerline. Each of the external notches is open at the front end and closed at the rear end. The outer ring is positioned at the front flange of the annular outer band to close the front end of each outer notch.

11. The fairing assembly of claim 9, wherein at least one fairing is axially separated and includes a front section and a rear section.

12. The fairing assembly of claim 9, wherein at least one fairing is circumferentially separated and includes a first side section and a second side section.

13. The fairing assembly of claim 9, wherein each recess includes a lip extending around the recess, and wherein an inner end of each fairing is received within the recess such that the inner end contacts the lip.

14. The fairing assembly of claim 9, wherein each recess includes a lip extending around the recess, and wherein an outer end of each fairing is received within the recess such that the outer end contacts the lip.

15. The fairing assembly according to claim 9, further comprising: Multiple seals, Among the multiple seals, the seal is positioned between the outer end of each fairing and the annular outer belt. Each of the plurality of seals includes a curved arm that is compressed between the outer end of the fairing and the annular outer belt. Each of the plurality of seals includes at least one flat wear surface between the outer end of the fairing and the annular outer belt.

16. The fairing assembly according to claim 9, further comprising: Multiple seals, Among the multiple seals, the seal is positioned between the inner end of each fairing and the annular inner band. Each of the plurality of seals includes a curved arm that is compressed between the inner end of the fairing and the annular inner band, and Each of the plurality of seals includes at least one wear surface of a plane between the inner end of the fairing and the annular inner band.

17. The fairing assembly according to claim 9, wherein, Multiple fairings are pinned to the inner end of each fairing with multiple pins, each of the multiple pins extending between the inner end of one of the multiple fairings and the annular inner strip.

18. The fairing assembly of claim 9, wherein the plurality of fairings, the inner annular band, and the outer annular band are each formed of a ceramic matrix composite material.

19. A method for assembling a cowling assembly in a gas turbine engine, the method comprising: An annular inner band is installed in a gas turbine engine, the annular inner band defining a plurality of recesses; Insert the inner end of each of the multiple fairings into the recess of the multiple recesses; The annular outer band is slidably positioned relative to the plurality of fairings, such that the outer end of each of the plurality of fairings is received in an outer recess of one of the plurality of outer recesses defined by the annular outer band; and A pin extends radially through the annular outer band, wherein the pin is configured to allow the annular outer band to expand radially. The annular inner band is a single-piece, integral structure that extends 360° around the axial centerline, and The annular outer band is a single-piece, integral structure that extends 360° around the axial centerline.

20. The method of claim 19, wherein the annular outer strip slides into place from the front end of the fairing assembly toward the rear end of the fairing assembly.

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