Composite airfoil assembly for a turbine engine

Abstract

A composite airfoil assembly for a turbine engine includes an airfoil defining an airfoil interior and an inner support structure at least partially located within the airfoil interior. The inner support structure may include interwoven fibers defining a three-dimensional structure. A laminate cover surrounds at least a portion of the inner support structure.

Description

Technical Field

[0001] The present disclosure relates generally to turbine engine airfoil assemblies and, more particularly, to composite airfoil assemblies. Background Art

[0002] A turbine engine (and in particular a gas or combustion turbine engine) is a rotary engine that extracts energy from a gas flow that passes through a fan having a plurality of fan blades and enters the engine core through a compressor section, a combustor, and a turbine section in an axial flow arrangement. The compressor section and the turbine section include one or more compressor stages and one or more turbine stages, respectively, wherein each stage is formed by a set of rotating blades adjacent to a set of stationary blades.

[0003] During operation, air is drawn into the compressor section by the fan, pressurized by one or more compressor stages in the compressor section, and then mixed with fuel in the combustor to generate hot combustion gases. The combustion gases flow downstream through the turbine section, where the air expands and drives the rotation of one or more turbine stages. The rotation of the turbine stage can also drive the rotation of the upstream fan and compressor stage.

[0004] In some examples, turbine engine components, including stationary or rotating components, may include composite materials. Composite materials typically include a fiber reinforced matrix and exhibit a high strength-to-weight ratio. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] A full and enabling disclosure of the present disclosure, including the best mode thereof, to one of ordinary skill in the art is set forth in the specification with reference to the accompanying drawings, in which:

[0006] Figure 1 is a schematic cross-sectional view of a turbine engine according to various aspects described herein.

[0007] Figure 2 is suitable for use in accordance with the various aspects described herein Figure 1 Schematic perspective view of a composite airfoil assembly and disk used within a turbine engine.

[0008] Figure 3 yes Figure 2 A schematic perspective view of a composite airfoil assembly is shown, and an inner support structure according to various aspects described herein.

[0009] Figure 4 yes Figure 2 Schematic side view of a composite airfoil assembly showing an inner support structure having multiple cores according to various aspects described herein.

[0010] Figure 5 It is taken along line VV Figure 4Cross-sectional view of a composite airfoil assembly.

[0011] Figure 6 Is suitable for Figure 1 Turbine engines and Figure 2 A schematic side view of another composite airfoil assembly for use with a disk of FIG. 1 and illustrating another inner support structure according to various aspects described herein.

[0012] Figure 7 It is taken along line VII-VII Figure 6 Cross-sectional view of a composite airfoil assembly.

[0013] Figure 8 Is applicable to Figure 1 Turbine engines and Figure 2 A schematic side view of another composite airfoil assembly for use with a disk of FIG. 1 and showing another inner support structure having a set of pins according to various aspects described herein.

[0014] Fig. 9 It is taken along line IX-IX Figure 8 Cross-sectional view of a composite airfoil assembly.

[0015] Fig.10 Is applicable to Figure 1 Turbine engines and Figure 2 A schematic side view of another composite airfoil assembly for use with a disk of FIG. 1 and showing another inner support structure having another set of pins according to various aspects described herein.

[0016] Fig.11 It is taken along the line XI-XI Fig.10 Cross-sectional view of a composite airfoil assembly.

[0017] Fig.12 According to various aspects described herein, it is suitable for use in a composite airfoil component (including Figure 2 , Figure 6 , Figure 8 or Fig.10 Schematic cross-sectional view of a three-dimensional woven material used in a composite airfoil assembly.

[0018] Fig.13 is a flow chart illustrating a method of forming a composite airfoil assembly according to various aspects described herein. DETAILED DESCRIPTION

[0019] Aspects disclosed herein relate to composite airfoil assemblies. For purposes of illustration, the present disclosure will be described with respect to a turbine engine airfoil assembly, and more specifically, with respect to a composite airfoil assembly within a fan section of a turbine engine. However, it should be understood that the aspects of the present disclosure described herein are not limited thereto and may have general applicability within other engines or within other turbine engine sections. For example, aspects of the present disclosure may be applied to composite airfoil assemblies in other engines or vehicles, and may also be used to provide benefits in industrial, commercial, and residential applications.

[0020] The composite airfoil assembly can be used in one or more positions within a turbine engine. For example, the composite airfoil assembly is suitable as a fan blade in the fan section of a turbine engine. Other positions (such as the compressor section and the turbine section) are also conceivable. The composite airfoil assembly can be installed in a variety of ways. One such installation is to fix the blade directly or via a pitch control assembly to the rotator of the fan section. Regardless of where the composite airfoil assembly is located, a suitable mounting member is a disk having complementary grooves to receive dovetails, wherein the grooves are circumferentially spaced around the periphery of the disk. The composite airfoil assembly and the disk can form a rotating assembly together, so that the composite airfoil assembly is a composite blade assembly.

[0021] As used herein, the term "upstream" refers to the direction opposite to the direction of fluid flow, while the term "downstream" refers to the direction in the same direction as the direction of fluid flow. The terms "front" or "frontward" may mean in front of something, and "rear" or "rearward" may mean behind something. For example, when used in relation to fluid flow, front / front refers to the upstream direction, and rear / rearward refers to the downstream direction.

[0022] Furthermore, as used herein, the term "radial" or "radially" refers to a direction away from a common center. For example, in the overall context of a turbine engine, radial refers to a direction along a ray extending between a central longitudinal axis of the engine and an outer periphery of the engine. Furthermore, as used herein, the term "group" or a "group" of elements may be any number of elements, including only one.

[0023] Additionally, as used herein, the term "fluid" or iterations thereof may refer to any suitable fluid within a gas turbine engine, at least a portion of which is exposed to, for example, but not limited to, combustion gases, ambient air, a pressurized gas stream, a working gas stream, or any combination thereof. It is also contemplated that the gas turbine engine may be other suitable turbine engines, such as, but not limited to, a steam turbine engine or a supercritical carbon dioxide turbine engine. As non-limiting examples, the term "fluid" may refer to steam in a steam turbine engine, or to carbon dioxide in a supercritical carbon dioxide turbine engine.

[0024] All directional references (e.g., radial, axial, proximal, distal, upper, lower, upward, downward, left, right, lateral, front, rear, top, bottom, above, below, vertical, horizontal, clockwise, counterclockwise, upstream, downstream, forward, backward, etc.) are used for identification purposes only to help the reader understand the present disclosure and do not create limitations, particularly limitations on the position, orientation, or use of the disclosed aspects described herein. Connection references (e.g., attach, couple, fix, fasten, connect, and engage) will be interpreted broadly and may include intermediate members between sets of elements and relative movement between elements, unless otherwise indicated. Therefore, a connection reference does not necessarily mean that the two elements are directly connected and fixed relative to each other. The exemplary drawings are for illustration purposes only, and the dimensions, positions, orders, and relative sizes reflected in the attached drawings may vary.

[0025] As used herein, the term "composite" refers to a component having two or more materials. A composite can be a combination of at least two or more metals, non-metals, or a combination of metal and non-metal elements or materials. Examples of composite materials can be, but are not limited to, polymer matrix composites (PMC), ceramic matrix composites (CMC), metal matrix composites (MMC), carbon fibers, polymer resins, thermoplastic resins, bismaleimide (BMI) materials, polyimide materials, epoxy resins, glass fibers, and silicon matrix materials.

[0026] As used herein, "composite component" refers to a structure or component comprising any suitable composite material. A composite component, such as a composite airfoil, may include several layers or several layups of composite materials. The stiffness, material, and dimensions of the layers or layups may vary to achieve a desired composite component or composite portion of a component having a predetermined weight, size, stiffness, and strength.

[0027] One or more layers of adhesive may be used to form or join the composite parts. The adhesive may include resins and phenolics, where the adhesive may require curing at elevated temperatures or other hardening techniques.

[0028] As used herein, "polymer matrix composites" or "PMCs" refer to a class of materials. As an example, PMC materials are defined in part by prepregs, which are reinforcing materials pre-impregnated with a polymer matrix material (e.g., a thermosetting resin or a thermoplastic resin). Non-limiting examples of processes for producing thermoplastic prepregs include: hot melt prepregs, in which a fiber reinforcement is pulled through a molten bath of resin; and powder prepregs, in which resin is deposited onto the fiber reinforcement, as a non-limiting example, electrostatically deposited onto the fiber reinforcement, and then adhered to the fibers, as a non-limiting example, in an oven or with the help of heated rollers. Prepregs can be in the form of unidirectional tapes or woven fabrics, which are then stacked on top of each other to form the desired number of stacked plies of a part.

[0029] In a non-limiting example of forming a composite part, multilayer prepregs can be stacked to the desired thickness and orientation of the composite part, and the resin can be subsequently cured and solidified to provide a fiber reinforced composite part. The resin used for PMC matrix materials can be generally classified as a thermosetting resin or a thermoplastic resin. Thermoplastic resins are generally classified as polymers that can be repeatedly softened and flowed when heated and can be hardened due to physical changes rather than chemical changes when fully cooled. The famous example categories of thermoplastic resins include nylon, thermoplastic polyesters, polyaryletherketones and polycarbonate resins. It has been envisioned that the specific examples of high-performance thermoplastic resins for aerospace applications include polyetheretherketone (PEEK), polyetherketoneketone (PEKK), polyetherimide (PEI), polyaryletherketone (PAEK) and polyphenylene sulfide (PPS). On the contrary, once fully cured into a hard rigid solid, thermosetting resins will not experience significant softening when heated, but will thermally decompose when fully heated. The famous examples of thermosetting resins include epoxy resins, bismaleimide (BMI) and polyimide resins.

[0030] In another non-limiting example, in addition to or as a substitute for prepreg layering, woven fabrics or braided fabrics can be used to form composite parts. A non-limiting example of woven fabrics can include dry carbon fibers woven together with thermoplastic polymer fibers or filaments. A non-limiting example of a braided architecture can include dry carbon fibers and thermoplastic polymer fibers braided together in a multi-strand arrangement. In some non-limiting examples, by selecting or customizing the relative concentrations of thermoplastic fibers and reinforcing fibers that have been woven or braided together, various properties of composite parts, such as fiber volume, material strength, stiffness, impact resistance, etc., can be customized. For example, in a non-limiting example of a braided composite part with glass fiber, carbon fiber and thermoplastic fiber, carbon fiber concentration can be selected to provide material strength, glass fiber concentration can be selected to enhance impact resistance, which is a design feature of parts located near the engine inlet, and thermoplastic fiber concentration can be selected to combine the properties of fibers in the woven fabric.

[0031] In another non-limiting example, in addition to prepreg, weaving or plaiting or as a substitute for prepreg, weaving or plaiting, resin transfer molding (RTM) can be used to form composite parts.RTM provides an example of "out of autoclave" (OOA) processing, in which composite parts can be formed and cured without the need for autoclave curing environment.Usually, RTM includes applying dry fiber or matrix material to a mold or cavity.Dry fiber or matrix material can include prepreg, plaiting material, woven material or any combination thereof.The placement or application of dry fiber or matrix material can be manual or automatic.Resin can then be pumped into or otherwise provided to a mold or cavity to impregnate dry fiber or matrix material.The combination of impregnated fiber or matrix material and resin is then cured and removed from the mold.Dry fiber or matrix material can also be molded to shape composite parts or guide resin.In some examples using prepreg stacks, the same resin used to form prepreg stacks can also be injected into a mold or cavity to form composite parts in a process called "same qualified resin transfer molding" (SQRTM). It is further contemplated that RTM may be vacuum assisted in a process known as "vacuum assisted resin transfer molding" (VARTM). In this case, air may be removed from the mold as the resin is drawn into the mold prior to heating or curing. Optionally, additional layers or reinforcements of materials other than the dry fiber or matrix material may also be included or added prior to heating or curing. In some examples, the composite part may be post-cured after removal from the mold.

[0032] As used herein, "ceramic matrix composite" or "CMC" refers to a class of materials having reinforcing fibers in a ceramic matrix. Typically, the reinforcing fibers provide structural integrity to the ceramic matrix. Some examples of reinforcing fibers may include, but are not limited to, non-oxide silicon-based materials (e.g., silicon carbide, silicon nitride, or mixtures thereof), non-oxide carbon-based materials (e.g., carbon), oxide ceramics (e.g., silicon oxycarbide, silicon oxynitride, aluminum oxide (Al2O3), silicon dioxide (SiO2), aluminosilicates (such as mullite), or mixtures thereof), or mixtures thereof.

[0033] Some examples of ceramic matrix materials may include, but are not limited to, non-oxide silicon-based materials (e.g., silicon carbide, silicon nitride, or mixtures thereof), oxide ceramics (e.g., silicon oxycarbide, silicon oxynitride, aluminum oxide (Al2O3), silicon dioxide (SiO2), aluminosilicates, or mixtures thereof), or mixtures thereof. Optionally, ceramic particles (e.g., oxides of Si, Al, Zr, Y, and combinations thereof) and inorganic fillers (e.g., pyrophyllite, wollastonite, mica, talc, kyanite, and montmorillonite) may also be included in the ceramic matrix.

[0034] In general, specific CMCs can be referred to as their fiber type / matrix type combination. For example, C / SiC is carbon fiber reinforced silicon carbide, SiC / SiC is silicon carbide fiber reinforced silicon carbide, SiC / SiN is silicon carbide fiber reinforced silicon nitride, SiC / SiC-SiN is silicon carbide fiber-reinforced silicon carbide / silicon nitride matrix mixture, etc. In other examples, CMCs can be composed of a matrix and reinforcing fibers comprising oxide-based materials such as aluminum oxide (Al2O3), silicon dioxide (SiO2), aluminosilicates, and mixtures thereof. Aluminosilicates can include crystalline materials such as mullite (3Al2O3·2SiO2), as well as glassy aluminosilicates.

[0035] In certain non-limiting examples, the reinforcing fibers may be bundled and / or coated before being included in the matrix. For example, the fiber bundles may be formed into reinforcing tapes, such as unidirectional reinforcing tapes. Multiple tapes may be stacked together to form a preform component. The fiber bundles may be impregnated with a slurry composition before or after forming the preform. The preform may then be subjected to heat treatment and subsequent chemical treatment to obtain a component formed of a CMC material having a desired chemical composition. For example, the preform may undergo curing or burnout to produce a high coke residue in the preform, and then melt infiltrated with silicon, or undergo curing or pyrolysis to produce a silicon carbide matrix in the preform, and then chemical vapor infiltration with silicon carbide. Additional steps may be taken to improve the densification of the preform, by injecting the preform with a liquid resin or polymer before or after chemical vapor infiltration, and then performing a heat treatment step to fill the voids with silicon carbide. CMC materials as used herein may be formed using any known or later developed method including, but not limited to, melt infiltration, chemical vapor infiltration, polymer infiltration pyrolysis (PIP), or any combination thereof.

[0036] Such materials, along with certain monolithic ceramics (i.e., ceramic materials without reinforcement materials), are particularly useful for higher temperature applications. In addition, these ceramic materials are lightweight compared to superalloys, yet still provide strength and durability to components made therefrom. As a result, such materials are currently being considered for use in many gas turbine components used in the higher temperature sections of gas turbine engines (such as airfoils (e.g., turbines and buckets), combustors, shrouds, and other components) that would benefit from the lighter weight and higher temperature capabilities that these materials can provide.

[0037] The term "metal" as used herein refers to materials including metals such as, but not limited to, titanium, iron, aluminum, stainless steel, and nickel alloys. A metal material or alloy may be a combination of at least two or more elements or materials, at least one of which is a metal.

[0038] Figure 1 is a schematic cross-sectional view of a turbine engine 10 for an aircraft. The turbine engine 10 has a generally longitudinally extending axis or centerline 12 extending from a front portion 14 to an aft portion 16. The turbine engine 10 includes, in downstream serial flow relationship: a fan section 18 including a fan 20; a compressor section 22 including a supercharger or low pressure (LP) compressor 24 and a high pressure (HP) compressor 26; a combustion section 28 including a combustor 30; a turbine section 32 including an HP turbine 34 and an LP turbine 36; and an exhaust section 38.

[0039] The fan section 18 includes a fan case 40 surrounding the fan 20. The fan 20 includes a plurality of fan blades 42 radially arranged about the engine centerline 12. The HP compressor 26, the combustor 30, and the HP turbine 34 form a core 44 of the turbine engine 10, which generates combustion gases. The core 44 is surrounded by a core case 46, which may be coupled to the fan case 40.

[0040] An HP shaft or spool 48 disposed coaxially about the engine centerline 12 of the turbine engine 10 drivingly connects the HP turbine 34 to the HP compressor 26. An LP shaft or spool 50 disposed coaxially about the engine centerline 12 of the turbine engine 10 within the larger diameter annular HP spool 48 drivingly connects the LP turbine 36 to the LP compressor 24 and the fan 20. The spools 48, 50 are rotatable about the engine centerline and are coupled to a plurality of rotatable elements that may collectively define a rotor 51.

[0041] The LP compressor 24 and the HP compressor 26 each include a plurality of compressor stages 52, 54, wherein a set of compressor blades 56, 58 rotate relative to a corresponding set of static compressor vanes 60, 62 to compress or pressurize a fluid flow through the stage. In a single compressor stage 52, 54, the plurality of compressor blades 56, 58 may be arranged in a ring and may extend radially outward from a blade platform to a blade tip relative to the engine centerline 12, with the corresponding static compressor vanes 60, 62 positioned upstream and adjacent to the rotating compressor blades 56, 58. Notably, Figure 1 The numbers of blades, buckets, and compressor stages shown in FIG. 5 are selected for illustration purposes only, and other numbers are possible.

[0042] Compressor blades 56, 58 for one stage of the compressor may be mounted to (or integrated into) a disk 61 mounted to a corresponding one of the HP and LP spools 48, 50. Static compressor vanes 60, 62 for one stage of the compressor may be mounted to the core housing 46 in a circumferential arrangement.

[0043] The HP turbine 34 and the LP turbine 36 each include a plurality of turbine stages 64, 66, wherein a set of turbine blades 68, 70 rotate relative to a corresponding set of static turbine vanes 72, 74 (also referred to as nozzles) to extract energy from a fluid flow passing through the stage. In a single turbine stage 64, 66, the plurality of turbine blades 68, 70 may be arranged in a ring and may extend radially outward relative to the engine centerline 12, while the corresponding static turbine vanes 72, 74 are positioned upstream and adjacent to the rotating turbine blades 68, 70. Notably, Figure 1 The number of blades, buckets, and turbine stages shown in FIG. 5 are selected for illustrative purposes only, and other numbers are possible.

[0044] Turbine blades 68, 70 for one stage of the turbine may be mounted to a disk 71 mounted to a corresponding one of the HP and LP spools 48, 50. Turbine buckets 72, 74 for one stage of the compressor may be mounted to the core housing 46 in a circumferential arrangement.

[0045] Complementing the rotor portion, the stationary portion of the turbine engine 10, such as the stationary blades 60, 62, 72, 74 in the compressor section 22 and the turbine section 32, are also individually or collectively referred to as stators 63. Thus, the stator 63 may refer to the combination of non-rotating elements throughout the turbine engine 10.

[0046] In operation, the airflow exiting the fan section 18 is split so that a portion of the airflow is directed into the LP compressor 24, which then supplies the pressurized airflow 76 to the HP compressor 26, which further pressurizes the air. The pressurized airflow 76 from the HP compressor 26 is mixed with the fuel in the combustor 30 and ignited, thereby generating combustion gases. The HP turbine 34 extracts some work from these gases, which drives the HP compressor 26. The combustion gases are exhausted into the LP turbine 36, which extracts additional work to drive the LP compressor 24, and the exhaust gas is ultimately exhausted from the turbine engine 10 via the exhaust section 38. The drive of the LP turbine 36 drives the LP spool 50 to rotate the fan 20 and the LP compressor 24.

[0047] A portion of the pressurized air flow 76 may be extracted from the compressor section 22 as bleed air 77. The bleed air 77 may be extracted from the pressurized air flow 76 and provided to engine components that require cooling. The temperature of the pressurized air flow 76 entering the combustor 30 is significantly increased to above the bleed air temperature. The bleed air 77 may be used to reduce the temperature of core components downstream of the combustor. The bleed air 77 may also be utilized by other systems.

[0048] The remaining portion of the airflow, referred to as bypass airflow 78, bypasses the LP compressor 24 and the engine core 44 and exits the turbine engine 10 through a stationary vane row at the fan exhaust side 84, and more specifically, exits the turbine engine 10 through an exit guide vane assembly 80 (including a plurality of airfoil guide vanes 82) at the fan exhaust side 84. More specifically, a circumferential row of radially extending airfoil guide vanes 82 are used adjacent the fan section 18 to exert some directional control on the bypass airflow 78.

[0049] Some of the air supplied by the fan 20 may bypass the engine core 44 and be used to cool portions of the turbine engine 10, particularly the hot portions, and / or to cool or power other aspects of the aircraft. In the case of a turbine engine, the hot portions of the engine are typically downstream of the combustor 30, particularly the turbine section 32, with the HP turbine 34 being the hottest portion as it is located directly downstream of the combustion section 28. Other sources of cooling fluid may be, but are not limited to, fluid discharged from the LP compressor 24 or the HP compressor 26.

[0050] Figure 2 Is suitable for Figure 1 Schematic perspective view of a disk 90 and a composite airfoil assembly 100 (also referred to herein as "airfoil assembly 100") for use within a turbine engine 10 of FIG. Disk 90 is suitable for use as disks 61, 71 ( Figure 1 ) or any other disk, such as, in a non-limiting example, a disk within a fan section 18 of a turbine engine 10. The airfoil assembly 100 may be rotating or non-rotating, such that the airfoil assembly 100 may include static compressor blades 60, 62 ( Figure 1 ), the set of compressor blades 56, 58 ( Figure 1 ), static turbine blades 72, 74 ( Figure 1 ), the group of turbine blades 68, 70 ( Figure 1 ) or at least one of the plurality of fan blades 42. In one non-limiting example, the airfoil assembly 100 may include a fan segment 18 ( Figure 1 ) and is configured to move during operation within the turbine engine 10 ( Figure 1 ) rotates at a speed between 1000-2500RPM.

[0051] For reference purposes, a set of relative reference directions and coordinate systems are Figure 2 , and applies to the airfoil assembly 100 and the disk 90. ​​The axial direction A extends from front to rear and is shown as extending partially into the page. The radial direction R is shown as extending perpendicular to the axial direction A. The circumferential direction C is defined circumferentially around the axial direction A. In other words, the circumferential direction C can be defined as a ray extending locally and orthogonally from the radial direction R, as shown.

[0052] The disk 90 may include a disk outer surface 92. A plurality of slots 94 may be disposed in the disk outer surface 92 and arranged circumferentially around the disk 90, as shown. Each slot 94 may be configured to receive a corresponding airfoil assembly 100. In addition, the disk 90 may rotate about an axis 96 or may be stationary. In the event that the disk 90 is stationary, it should be understood that the disk 90 may be any suitable stationary portion of the turbine engine to which the airfoil assembly 100 may be coupled, such as, but not limited to, a belt, a shroud, a casing, etc. In one non-limiting example, the axis 96 is aligned with the engine centerline 12 ( Figure 1 ) coincides. In another non-limiting example, the axis 96 is parallel to the engine centerline 12. In yet another non-limiting example, the axis 96 intersects or forms an angle with the engine centerline 12.

[0053] In some embodiments, the axial direction A may coincide with the axis 96. In this case, it should be understood that the radial direction R is orthogonal to the axis 96, and the circumferential direction C extends circumferentially around the axis 96. In addition, in some embodiments, the axial direction A may also coincide with the engine centerline 12 ( Figure 1 ) coincides. In this case, the radial direction R is orthogonal to the engine centerline 12 ( Figure 1 ), and the circumferential direction C extends circumferentially around the turbine engine 10 relative to the engine centerline 12.

[0054] The airfoil assembly 100 includes an airfoil 110 defining an airfoil interior 106 and having an exterior surface 105. The exterior surface 105 extends axially between a leading edge 111 and a trailing edge 112, and also extends radially between a root 113 and a tip 114. In the example shown, the airfoil 110 also defines a pressure side 115 and a suction side 116. In another non-limiting example, the airfoil 110 may be a symmetrical airfoil such that the exterior surface 105 is axially symmetrical.

[0055] In the illustrated example, the airfoil assembly 100 also includes a dovetail 120 extending from the root 113 of the airfoil 110, as shown. The dovetail 120 extends radially between a first end 121 and a second end 122. The first end 121 defines a radially inner surface of the dovetail 120. The second end 122 forms a transition between the dovetail 120 and the airfoil 110. The dovetail 120 also defines a dovetail interior 126, as shown. In some embodiments, the airfoil 110 and the dovetail 120 may also be integrally or unitarily formed with each other.

[0056] Composite airfoil assembly 100 is assembled with disk 90 by axially inserting at least a portion of dovetail 120 through corresponding slot 94. Airfoil 110 extends radially outward from slot 94. In some embodiments, second end 122 coincides with root 113 of airfoil 110 such that root 113 is aligned with disk outer surface 92.

[0057] The composite airfoil assembly 100 is held in place by frictional contact with the slot 94 or may be coupled to the slot 94 via any suitable coupling method, such as, but not limited to, welding, bonding, fastening, etc. Although only a single composite airfoil assembly 100 is shown, any number of composite airfoil assemblies 100 may be coupled to the disk 90. ​​As a non-limiting example, a number of composite airfoil assemblies 100 may be provided corresponding to the total number of slots 94 around the disk 90.

[0058] Steering Figure 3 , the composite airfoil assembly 100 is shown in a schematic perspective view. An inner support structure 130 is disposed within the airfoil interior 106 of the airfoil assembly 100. The inner support structure 130 may be positioned within at least one of the airfoil 110 or the dovetail 120. In the non-limiting example shown, the inner support structure 130 extends radially within both the airfoil 110 and the dovetail 120.

[0059] The inner support structure 130 may include a plurality of cores 140 (shown in dotted lines). The plurality of cores 140 may include one or more composite core materials. In some embodiments, at least one of the plurality of cores 140 may include interwoven fibers that define a three-dimensional core structure. Such interwoven fibers may include, but are not limited to, single strands of fibers, fiber tows, braided fibers, woven fibers, twisted fibers, knitted fibers, yarns, or combinations thereof that form or define a three-dimensional core structure. For example, in some embodiments, fiber tows may be woven and subsequently interwoven to form a three-dimensional core structure. It is also contemplated that each of the plurality of cores 140 may include such a three-dimensional core structure as described above.

[0060] In the illustrated example, the plurality of cores 140 includes a first core 140a, a second core 140b, and a third core 140c. It should be understood that the plurality of cores 140 may include any number of cores, including four or more. In the illustrated non-limiting example, the first core 140a is positioned within the dovetail 120 and extends radially into the airfoil 110 at the root 113. The second core 140b is positioned radially outward from the first core 140a and extends along the leading edge 111 toward the tip 114. The third core 140c is positioned radially outward from the first core 140a and is also axially arranged with the second core 140b such that the third core 140c extends along the trailing edge 112 toward the tip 114.

[0061] The laminate cover 150 covers and surrounds the inner support structure 130, including the first core 140a, the second core 140b, and the third core 140c. In some embodiments, the laminate cover 150 defines the exterior surface 105 of the composite airfoil assembly 100. In some embodiments, the laminate cover 150 may be at least partially covered by one or more additional layers that define the exterior surface 105.

[0062] The laminate cover 150 may be in the form of a composite skin. As used herein, "skin" refers to a material layer having multiple plies or multiple layers of composite material. The laminate cover 150 may include a plurality of stacked composite plies formed by any suitable process, including, in a non-limiting example, at least one of pre-impregnated fibers in a polymer matrix, automated fiber placement (AFP), dry fiber placement (DFP), or customized fiber placement (TFP).

[0063] In this manner, the plurality of cores 140 and the laminate cover 150 may each comprise a composite material having a different material structure. Some or all of the plurality of cores 140 may have a corresponding three-dimensional core structure defined by interwoven fibers, such as a woven core structure or a braided core structure as described above. The laminate cover 150 may include a plurality of plies arranged in a stacked manner as described above. It is contemplated that the density of the laminate cover 150 may be greater than the density of the three-dimensional structure of the cores in the plurality of cores 140. In a non-limiting example, the cores in the plurality of cores 140 may have a density of 0.2–1.6 g / cm 3 The three-dimensional core structure between 1.4-1.6 g / cm 3 The density between.

[0064] Reference now Figure 4 , shows a schematic side view of an airfoil assembly 100 . The inner support structure 130 is shown in solid lines, and the laminate cover 150 is shown in phantom lines, including the airfoil 110 and the dovetail 120 .

[0065] In the example shown, the first core 140a is radially spaced from each of the second core 140b and the third core 140c, and the second core 140b is axially spaced from the third core 140c, although this need not be the case. It is also contemplated that in some embodiments, at least some of the plurality of cores 140 may be in an abutting or physical contacting arrangement.

[0066] The plurality of cores 140 may include cores having the same or different geometric profiles. As shown, the first core 140a, the second core 140b, and the third core 140c define corresponding first core widths 141a, second core widths 141b, and third core widths 141c along the axial direction A. In the non-limiting example shown, the average value of the second core width 141b is less than the average value of the first core width 141a. In addition, in the non-limiting example shown, the average value of the third core width 141c is less than the average value of the first core width 141a. It is contemplated that each of the plurality of cores 140 may have any suitable width, including a constant width or a non-constant width.

[0067] Additionally, the first core 140a, the second core 140b, and the third core 140c can each define a respective first height 142a, a second height 142b, and a third height 142c along the radial direction R. In the non-limiting example shown, the average value of the second height 142b is greater than the average value of the first height 142a. Additionally, in the non-limiting example shown, the average value of the third height 142c is greater than the average value of the first height 142a. It is contemplated that each of the plurality of cores 140 can have any suitable height, including a constant height or a non-constant height.

[0068] A set of pins 160 may also be provided in the inner support structure 130. In a non-limiting example, the set of pins 160 may be inserted into one or more of the plurality of cores 140 for maintaining relative arrangement or positioning, improving stability, or preventing delamination. In the non-limiting example shown, the set of pins 160 includes a pin inserted into each of the first, second, and third cores 140a, 140b, 140c. Additionally or alternatively, the set of pins 160 may include a single pin extending through three or more of the plurality of cores 140. Additionally or alternatively, the set of pins 160 may include a plurality of pins inserted into a single core of the plurality of cores 140. In addition, although the set of pins 160 is schematically shown as a rectangle, it should be understood that the set of pins 160 may have any suitable geometric profile, including round, conical, flanged, single-tip, double-tip, etc. It should be understood that, in some examples, the set of pins 160 may be used to fix or maintain a spaced arrangement between the plurality of cores 140 , or, in some examples, to maintain an abutting arrangement between the plurality of cores 140 .

[0069] Furthermore, it should be understood that the airfoil assembly 100 may still provide Figure 4 Additional pins not shown in the drawings may be provided. Such additional pins may extend in any suitable direction. Such additional pins may also be inserted into the laminate cover 150 or positioned entirely within the laminate cover 150, spaced apart from the core set 140, thereby providing increased stability or mitigating potential delamination of the laminate cover 150.

[0070] Figure 5 The airfoil assembly 100 is shown along Figure 4 1. A cross-sectional view of line VV of FIG. 1. In this view, the inner support structure 130 is shown having a plurality of cores 140, in particular a second core 140b and a third core 140c, and having a laminate cover 150 forming the outer surface 105.

[0071] A local spacing distance 145 can be defined between adjacent cores in the plurality of cores 140. In the example shown, a local spacing distance 145 is shown between the second core 140b and the third core 140c. It is contemplated that the laminate cover 150 can at least partially fill the local spacing distance 145. In the example shown, the laminate cover 150 completely fills the local spacing distance 145, so that the second core 140b and the third core 140c are each completely surrounded by the laminate cover 150. In some embodiments, the laminate cover 150 can partially fill the local spacing distance 145, so that a gap can exist between the second and third cores 140b, 140c. Additionally or alternatively, a resin material can be introduced into the local spacing distance 145 to form a resin-rich gap between the second and third cores 140b, 140c.

[0072] In addition, the second core 140b and the third core 140c are each shown as having a woven fiber architecture, for example, formed using woven fiber plies, although this need not be the case. It is also contemplated that, in a non-limiting example, any one or both of the second core 140b and the third core 140c may include a woven fiber architecture, for example, formed using woven fiber plies, or a combination of woven fiber plies and woven fiber plies stacked.

[0073] General reference Figure 1-5When forming the composite airfoil assembly 100, at least some of the plurality of cores 140 may be formed by stacking woven fiber plies or prepregs, braided fiber plies or prepregs, or a combination thereof into a desired core shape to form one or more precursors or layups. The precursors are then cured and optionally shaped using any suitable method (including by an RTM process as described above). The plurality of cores 140 may then be arranged, positioned, etc. (including by the set of pins 160 in some examples) to form the inner support structure 130. In some embodiments, a resin may be applied between adjacent cores in the plurality of cores 140 to at least partially fill the local spacing distance 145 in the inner support structure 130. A laminate cover 150 may then be formed on the inner support structure 130 (including by an RTM process in some embodiments), and the resulting component may be further cured or shaped to form the composite airfoil assembly 100. In addition, the laminate cover 150 can at least partially fill the localized spacing distance 145 in the inner support structure 130, including covering the resin layer within the localized spacing distance 145. Moreover, in some embodiments, the laminate cover 150 defines the exterior surface 105 of the composite airfoil assembly 100 as described above. Additionally or alternatively, additional layers, coverings, coatings, covers, etc. can be applied to the laminate cover 150 and define the exterior surface 105.

[0074] Reference now Figure 6 , showing the suitability with Figure 1 Turbine engines and Figure 2 Another composite airfoil assembly 200 (also referred to herein as “airfoil assembly 200”) for use with a composite disk of the present invention is disclosed. The airfoil assembly 200 is similar to the airfoil assembly 100. Therefore, like parts of the airfoil assembly 200 will be described using like numerals increased by 100, with the understanding that the description of like parts of the airfoil assembly 100 applies to the airfoil assembly 200 unless otherwise specified.

[0075] The airfoil assembly 200 is shown in a schematic side view. The airfoil assembly 200 includes an airfoil 210 defining an airfoil interior 206 and having an exterior surface 205 (shown in phantom). The exterior surface 205 extends axially between a leading edge 211 and a trailing edge 212, and also extends radially between a root 213 and a tip 214. The exterior surface 205 may additionally define a pressure side 215 and a suction side 216 (shown in phantom). Figure 7 ). The airfoil assembly 200 also includes a dovetail 220 extending from the root 213 and defining a dovetail interior 226.

[0076] The airfoil assembly 200 includes an inner support structure 230 (shown in solid lines) and a laminate cover 250 that defines an outer surface 205. The inner support structure 230 may include a plurality of cores 240. The plurality of cores 240 may include one or more composite core materials. In some embodiments, at least some of the plurality of cores 240 may include interwoven fibers that define a three-dimensional core structure. In a non-limiting example, such interwoven fibers may include single strands of fibers, fiber tows, woven fibers, plaited fibers, twisted fibers, knitted fibers, yarns, or combinations thereof. In some embodiments, single strands of fibers, fiber tows, woven fibers, plaited fibers, twisted fibers, knitted fibers, yarns, and the like may be woven together to form a three-dimensional core structure. In the example shown, the plurality of cores 240 include a first core 240a, a second core 240b, and a third core 240c. Although in Figure 6 2, but it is contemplated that the inner support structure 230 may include a plurality of pins similar to the set of pins 160 ( Figure 4 ) a set of pins.

[0077] One difference compared to the airfoil assembly 100 is that the first, second, and third cores 240a, 240b, 240c are radially aligned with the first core 240a disposed within the dovetail 210 and the root 213, the third core 240c disposed at the tip 214, and the second core 240b positioned between the first and third cores 240a, 240c. Another difference compared to the airfoil assembly 100 is that one or more of the plurality of cores 240 may include a central sub-core, structure, etc. In the example shown, the first core 240a includes a sub-core 246 (shown in phantom).

[0078] Go to Figure 7 , a cross-sectional view of the airfoil assembly 200 shows additional details of the sub-core 246, the first core 240a, and the laminated cover 250. It is envisioned that the sub-core 246 may include a lightweight material, including a flexible foam or a rigid foam, including polystyrene foam in a non-limiting example. It is envisioned that the sub-core 246 may have a material density that is less than or equal to the density of the surrounding core material of the first core 240a. In a non-limiting example, the first core 240a may be formed by applying a woven or woven ply to the sub-core 246, and then curing or shaping as described above. In another non-limiting example, the first core 240a may be formed by weaving fibers, yarns, woven materials, tows, etc. in a three-dimensional manner around the sub-core 246. In this way, due to the lightweight sub-core 246, the first core 240a can be constructed into a large overall shape with reduced weight. The laminated cover 250 may be formed or applied to the first core 240a, and optionally defines the outer surface 205 as described above.

[0079] Reference now Figure 8 , showing the suitability with Figure 1Turbine engines and Figure 2 Another composite airfoil assembly 300 (also referred to herein as “airfoil assembly 300”) for use with a disk of Figure 3-5 The airfoil assembly 100 and Figure 6 and Figure 7 Thus, like parts of the airfoil assembly 300 will be described using like numerals further increased by 100, with the understanding that the description of like parts of the airfoil assemblies 100, 200 applies to the airfoil assembly 300 unless otherwise noted.

[0080] The airfoil assembly 300 is shown in a schematic side view. The airfoil assembly 300 includes an airfoil 310 defining an airfoil interior 306 and having an exterior surface 305 (shown in phantom). The exterior surface 305 extends axially between a leading edge 311 and a trailing edge 312, and also extends radially between a root 313 and a tip 314. The airfoil assembly 300 also includes a dovetail 320 extending from the root 313 and defining a dovetail interior 326.

[0081] The airfoil assembly 300 includes an inner support structure 330 (shown in solid lines) and a laminated cover 350 defining an outer surface 305. The inner support structure 330 may include a plurality of cores 340. The plurality of cores 340 may include one or more composite core materials. In some embodiments, at least some of the plurality of cores 340 may include interwoven fibers defining a three-dimensional core structure. In a non-limiting example, such interwoven fibers may include single strands of fiber, fiber tows, braided fibers, woven fibers, twisted fibers, knitted fibers, yarns, or a combination thereof. In some embodiments, single strands of fiber, fiber tows, braided fibers, woven fibers, twisted fibers, knitted fibers, yarns, etc. may be woven together to form a three-dimensional core structure.

[0082] In the illustrated example, the plurality of cores 340 include a first core 340a and a second core 340b that are radially spaced apart. As shown, a local spacing distance 345 is defined between the first core 340a and the second core 340b. One difference compared to the airfoil assemblies 100, 200 is that the plurality of cores 340 are completely contained within the airfoil 310 and do not extend into the dovetail 320. It is contemplated that the laminated cover 350 may be constructed, stacked, etc. in the area of ​​the dovetail 320 to completely define the dovetail 320.

[0083] A set of pins 360 is provided with the inner support structure 330. Another difference compared to the airfoil assemblies 100, 200 is that the set of pins 360 includes a plurality of pins having different insertion depths, alignments or geometric profiles and inserted into the plurality of cores 340. In the illustrated example, the set of pins 360 includes a first pin 360a, a second pin 360b, a third pin 360c, a fourth pin 360d, and a fifth pin 360e. The first pin 360a, the second pin 360b, the third pin 360c, the fourth pin 360d, and the fifth pin 360e include respective first ends 361a, 361b, 361c, 361d, 361e and respective second ends 362a, 362b, 362c, 362d, 362e ( Figure 8-9 ) between the bodies 364a, 364b, 364c, 364d, 364e extending therebetween.

[0084] In the example shown, the first and second pins 360a, 360b are at least radially positioned so that the first ends 361a, 361b are radially outside the second ends 362a, 362b. The first ends 361a, 361b are inserted into the second core 340b, and the second ends 362a, 362b are inserted into the first core 340a. In the example shown, the third, fourth and fifth pins 360c, 360d, 360e are at least circumferentially positioned.

[0085] At least some of the pins in the set of pins 360 can be misaligned with each other and extend in different directions within the inner support structure 330. For example, in the example shown, the first pin 360a extends at least radially between the first core 340a and the second core 340b, and the fourth pin 360d extends at least circumferentially within the second core 340. In some embodiments, the first pin 360a and the fourth pin 360d can be orthogonal to each other. Additionally, in the example shown, the second pin 360b extends radially and axially between the first and second cores 340a, 340b, such that the first, second, and fourth pins 360a, 360b, 360d are all misaligned with each other.

[0086] In addition, at least some of the pins in the set of pins 360 can include one or more flanges for controlling the insertion depth into the set of cores 340. In the illustrated example, the first pin 360a includes flanges 366a, 366b, each extending from the body 364a and spaced apart from each of the first and second ends 361a, 362a. In this manner, the flanges 366a, 366b can define a predetermined or fixed insertion depth into the corresponding core 340a, 340b, thereby at least partially defining the local spacing distance 345, as shown.

[0087] It is contemplated that the set of pins 360 may have any suitable geometric profile, including a constant or variable body width, and including a symmetrical or asymmetrical body. In the illustrated example, a portion of the first pin 360a defines a body width 368a that is constant between the first end 361a and the second end 362a. Additionally, in the illustrated example, the second pin 360b defines a body width 368b that increases continuously from the first end 361b toward the second end 362b.

[0088] In a non-limiting example, it is contemplated that the pins in the set of pins 360 may extend to the exterior surface 305, or be fully inserted into and spaced from the exterior surface 305 of the laminate cover 350, or be fully inserted into and spaced from the set of cores 340. In the illustrated example, the first and second ends 361a, 362a of the first pin 360a are positioned within the respective second core 340b and first core 340a and spaced from the laminate cover 350. Additionally, the fourth pin 360d may have a second end 362d (shown in phantom) positioned within the second core 340b, and the fifth pin 360e may have a second end 362e extending out of the second core 340 and into the laminate cover 350. It should be appreciated that, in non-limiting examples, the set of pins 360 may extend through the airfoil assembly 300 in any direction, including extending vertically through the plurality of stacked plies in the laminate cover 350 or the set of cores 340 , or extending laterally along the plies in the laminate cover 350 or the set of cores 340 .

[0089] Steering Fig. 9 , along Figure 8 Line IX-IX shows an enlarged cross-sectional view of the airfoil assembly 300. More specifically, the airfoil 310 is shown between the pressure side 315 and the suction side 316, and pins 360a, 360b, 360c, 360d, 360e inserted into the second core 340b and the laminate cover 350 are shown.

[0090] The group of pins 360 may include any suitable material, including metal components, non-metal components, composite fiber materials, etc. For example, in a non-limiting example, the first pin 360a and the second pin 360b may each include a fiber pin material. In a non-limiting example, such a fiber pin material may include woven fibers, twisted fibers, plaited fibers, knitted fibers, yarns, tows, or single strands. More specifically, the second pin 360b may include a pin core 365 and a fiber wrap 367. In a non-limiting example, the pin core 365 may be metal, and the fiber wrap 367 may include fibers that are at least one of woven or spirally wound around the pin core 365. In a non-limiting example, the fiber wrap 367 may include at least one of glass fiber or composite fiber material. In some examples, prepreg may be used to form the composite fiber wrap 367. Regardless of the forming method used, the composite fiber wrap 367 may be constructed to form a second pin 360b having a desired width or geometric profile. In this manner, the set of pins 360 may include pins having a unitary body or a layered body using a single or multiple materials.

[0091] As described above, the first pin 360a and the second pin 360b are inserted into the set of cores 340 and are each spaced apart from the laminate cover 350. In addition, the third pin 360c extends at least circumferentially through the second core 340b, with the first end 361c extending to the exterior surface 305 and the second end 362c located within the laminate cover 350. The fourth pin 360d and the fifth pin 360e also extend at least circumferentially through the second core 340b. Both ends 361d, 362d of the fourth pin 360d and the first end 361e of the fifth pin 360e are positioned within the laminate cover 350 and spaced apart from the exterior surface 305. The second end 362e of the fifth pin 360e extends through the laminate cover 350 to the exterior surface 305.

[0092] In this manner, the inner support structure 330 may include the set of pins 360 extending into or through the set of cores 340 , providing relative positioning or arrangement of the set of cores 340 prior to application of the laminate cover 350 , and also providing improved stability of the airfoil assembly 300 during operation.

[0093] Reference now Fig.10 , showing the suitability with Figure 1 Turbine engines and Figure 2 Another composite airfoil assembly 400 (also referred to herein as "airfoil assembly 400") for use with a disk of Figure 3-5 The airfoil assembly 100, Figure 6 and Figure 7 The airfoil assembly 200, and Figure 8 and Fig. 9Thus, like parts of the airfoil assembly 400 will be described with like numerals further increased by 100, it being understood that the description of like parts of the airfoil assemblies 100, 200, 300 apply to the airfoil assembly 400 unless otherwise noted.

[0094] The airfoil assembly 400 is shown in a schematic side view. The airfoil assembly 400 includes an airfoil 410 defining an airfoil interior 406 and having an exterior surface 405 (shown in phantom). The exterior surface 405 extends axially between a leading edge 411 and a trailing edge 412, and also extends radially between a root 413 and a tip 414. The airfoil assembly 400 also includes a dovetail 420 extending from the root 413 and defining a dovetail interior 426.

[0095] The airfoil assembly 400 includes an inner support structure 430 (shown in solid lines) and a laminated cover 450 defining an outer surface 405. The inner support structure 430 may include a plurality of cores 440. The plurality of cores 440 may include one or more composite core materials. In some embodiments, at least some of the plurality of cores 440 may include interwoven fibers defining a three-dimensional core structure. In a non-limiting example, such interwoven fibers may include single strands of fiber, fiber tows, braided fibers, woven fibers, twisted fibers, knitted fibers, yarns, or a combination thereof. In some embodiments, single strands of fiber, fiber tows, braided fibers, woven fibers, twisted fibers, knitted fibers, yarns, etc. may be woven together to form a three-dimensional core structure.

[0096] In the illustrated example, the plurality of cores 440 include a first core 440a, a second core 440b, and a third core 440c that are radially aligned. The first core 440a may at least partially form the dovetail 420 and the root 413. The third core 440c may at least partially form the tip 414. The third core 440c may also include a sub-core similar to the sub-core 246 ( Figure 7 ) of the sub-core 446. The sub-core 446 may include a lightweight material, including, in some non-limiting examples, a rigid foam or a flexible foam.

[0097] A group of pins 460 can be arranged in the inner support structure 430. In the example shown, the group of pins 460 includes a first pin 460a, a second pin 460b and a third pin 460c. The first pin 460a can extend between the second core 440b and the third core 440c, and connect the second core 440b to the third core 440c. The third pin 460c can extend between the first core 440a and the second core 440b, and connect the first core 440a to the second core 440b. A difference compared to the airfoil assembly 100, 200, 300 is that the second pin 460b can extend through three cores. More specifically, the second pin 460b includes a first end 461b in the third core 440c, extends completely through the second core 440b, and includes a second end 462b in the first core 440a. In this manner, at least one pin in the set of pins 460 may extend between and connect at least the first core, the second core, and the third core.

[0098] In the illustrated example, the second pin 460b also includes a flange 466 spaced apart from the first end 461b. The flange 466 defines an insertion depth 469 into the third core 440c. Another difference compared to the airfoil assemblies 100, 200, 300 is that the second pin 460b can extend into the sub-core 446. In particular, in the non-limiting example shown, the first end 461b of the second pin 460b is positioned within the sub-core 446. It should be understood that in some embodiments, the insertion depth 469 can be selected, customized, etc. to position the second pin 460b within or through any suitable portion of the inner support structure 430, including extending completely through the sub-core 446.

[0099] Another difference compared to the airfoil assemblies 100, 200, 300 is that the airfoil assembly 400 may include a cap or shield 470 over a portion of the laminate cover 450 and defines a leading edge 411. Referring now to Fig.11 , the cross-sectional view of the airfoil assembly 400 shows that the shield 470 can extend axially along the laminate cover 450 and define at least a portion of the outer surface 405. In some non-limiting examples, the shield 470 can include a metallic material, a composite material, or a combination thereof. In some embodiments, the shield 470 can also include a single body or multiple discrete bodies that are coupled, bonded, etc. to the laminate cover 450. In this way, the shield 470 can provide increased strength or durability at the leading edge 411.

[0100] Another difference compared to airfoil assemblies 100, 200, 300 is that airfoil 410 may be in the form of a symmetrical airfoil where exterior surface 405 does not form a pressure side relative to a suction side. It will be appreciated that in some embodiments, airfoil 410 may include a pressure side and a suction side.

[0101] In the example shown, sub-core 446 comprises a foam material and is surrounded by the three-dimensional core structure of third core 440c. Laminate cover 450 surrounds third core 440c and defines a portion of exterior surface 405. Shield 470 defines leading edge 411 as described above and smoothly transitions to laminate cover 450.

[0102] Reference now Fig.12 , showing that they can be Figure 3-11 An exemplary woven component 500 for use in any or all of the airfoil assemblies 100 , 200 , 300 , 400 . For example, the woven component 500 may at least partially form one or more cores of the plurality of cores 140 , 240 , 340 , 440 .

[0103] A coordinate system is provided for reference and includes a horizontal axis representing 'X', a vertical axis representing 'Y' and a third axis representing 'Z' extending out of the page as shown. It should be understood that any of the axes X, Y, Z may be aligned with the axial direction A, radial direction R or circumferential direction C described above.

[0104] In the illustrated example, knitted component 500 defines a first side 501 vertically spaced apart from a second side 502. A component thickness 505 is defined between first and second sides 501, 502. In some non-limiting examples, component thickness 505 may be between 0.1-2 inches, or between 0.5-1 inches, or between 1-2 inches.

[0105] The woven component 500 can have a three-dimensional woven structure. More specifically, the woven component 500 can be formed by a three-dimensional weaving process, wherein the component thickness 505 is built during the weaving of the warp fibers 510, the weft fibers 520, and the transverse fibers 530. In some embodiments, such a weaving process can utilize a jacquard loom. In this way, the woven component 500 can be formed to a near net shape without the need for stacking layers to build component thickness.

[0106] As shown, for visual clarity, the woven component 500 shown has exaggerated spacing between the warp fibers 510, the weft fibers 520, and the transverse fibers 530, and it should be understood that the spacing distance between adjacent fibers in the woven component 500 can be any suitable size, including a tightly woven structure in which adjacent fibers are adjacent to each other, or a loosely woven structure in which adjacent fibers are spaced or separated from each other. It should also be understood that the warp fibers 510, the weft fibers 520, or the transverse fibers 530 may include single strands of fibers, fiber tows, woven fibers, braided fibers, twisted fibers, knitted fibers, yarns, etc., or combinations thereof.

[0107] Warp fibers 510 extend out of the page along the Z axis. In the non-limiting example shown, warp fibers 510 are oriented to form vertical columns 525 between first side 501 and second side 502, wherein adjacent columns 525 are vertically offset in a staggered arrangement, although this need not be the case. In some non-limiting examples, warp fibers 510 may form aligned columns, or have an asymmetric or irregular arrangement or spacing through knitted component 500, etc.

[0108] The weft fibers 520 extend horizontally and weave through the warp fibers 510, wherein each weft fiber 520 alternates vertically above and below each consecutive warp fiber 510, as shown. Additionally, in the example shown, adjacent weft fibers 520 are relatively woven around each warp fiber 510. In this manner, each warp fiber 510 can be vertically positioned between two adjacent weft fibers 520.

[0109] Transverse fibers 530 are woven through warp fibers 510 as well as weft fibers 520. As shown, transverse fibers 530 are aligned along the Z-axis and are woven vertically around each column 525 of warp fibers 510, extending through all weft fibers 520 between first side 501 in a through-thickness arrangement, although this need not be the case. In some non-limiting examples, transverse fibers 530 may be woven vertically through portions of columns 525 such that they do not extend to either or both of first side 501 or second side 502, or transverse fibers 520 may have an irregular distribution through knitted component 500, etc.

[0110] In this manner, woven component 500 may include fibers woven in a three-dimensional manner and having constant or non-constant fiber spacing, patterns, etc. Such an arrangement may provide customization of fiber density, such as constant or variable fiber density, in different portions of woven component 500. Such customization of fiber density may provide customization of material properties, including material strength, torsion, stiffness, fatigue durability, weight, etc.

[0111] Now go to Fig.13, a flow chart showing the formation of composite airfoil components (such as Figure 3-11 The method 600 includes forming an inner support structure (such as the inner support structure 130, 230, 330, 340) having at least a first core and a second core (such as the first core 140a, 240a, 340a, 440a, or the second core 140b, 240b, 340b, 440b) at 602, the first core and the second core each having a core material having at least one of fibers, yarns, braids, or tows.

[0112] In some embodiments, forming the inner support structure at 602 includes interweaving core materials (such as fibers, yarns, braids, tows, etc.) to define a three-dimensional core structure of at least one of the first core or the second core. Additionally or alternatively, forming the inner support structure at 602 includes braiding fibers, yarns, tows, braids, etc. through a three-dimensional braiding process to define a three-dimensional core structure of at least one of the first core or the second core. Additionally or alternatively, forming the inner support structure at 602 includes braiding three sets of core materials (such as fibers, yarns, braids, tows, etc.) along corresponding three different directions to define a three-dimensional braided core structure of at least one of the first core or the second core.

[0113] Additionally or alternatively, forming the inner support structure at 602 includes forming at least one of the first core or the second core around the sub-core. Additionally or alternatively, forming the inner support structure at 602 includes positioning at least one of the first core or the second core to at least partially form a dovetail, root, or tip of the composite airfoil assembly.

[0114] Additionally or alternatively, forming the inner support structure at 602 includes inserting at least one pin (such as the set of pins 460) into the first core and the second core, thereby connecting the first core to the second core. Additionally or alternatively, forming the inner support structure at 602 includes defining a separation distance between the first core and the second core via the at least one pin. Additionally or alternatively, forming the inner support structure at 602 includes inserting at least one pin into a sub-core within at least one of the first core or the second core. Additionally or alternatively, forming the inner support structure at 602 includes forming a composite pin by applying a composite material on a metal pin core.

[0115] The method 600 also includes applying a laminate cover (such as laminate cover 150, 250, 350, 450) to surround at least a portion of the inner support structure at 604. In some embodiments, applying the laminate cover at 604 also includes applying a plurality of stacked plies on the inner support structure. Additionally or alternatively, applying the laminate cover at 604 includes forming an exterior surface of the composite airfoil assembly. Additionally or alternatively, applying the laminate cover at 604 includes at least partially filling a spacing distance between the first core and the second core, such as local spacing distance 145, 345, with the laminate cover.

[0116] Optionally, method 600 may include at least partially filling a separation distance between the first core and the second core with a resin material, such as partial separation distances 145, 345. Optionally, applying a laminate cover at 604 includes covering the resin material with a laminate cover.

[0117] General reference Figure 1-13 It should be understood that aspects of the present disclosure may be mixed, combined, etc. to form a suitable embodiment for use in a turbine engine 10 ( Figure 1 ) Various composite airfoil assemblies used in the present invention. Some additional examples will be described below, it should be understood that such examples are illustrative and do not limit the present disclosure in any way.

[0118] In an exemplary embodiment, the airfoil assembly may include an airfoil defining an airfoil interior as described above and a dovetail defining an interior of the dovetail. The airfoil assembly may include an inner support structure having a plurality of cores covered with a laminated covering as described above. At least one of the plurality of cores may be positioned individually within the airfoil interior, individually within the dovetail interior, or positioned within both the airfoil interior and the dovetail interior. At least one of the plurality of cores may be formed with interwoven fibers defining a three-dimensional core structure as described above. Optionally, the three-dimensional core structure may have a smaller density than the laminated covering. Optionally, the inner support structure may include at least one pin connecting at least some of the plurality of cores together. Optionally, at least one of the plurality of cores may include a three-dimensional core structure and a sub-core having a material composition different from that of the surrounding three-dimensional core structure. Optionally, the sub-core may include a foam material. Optionally, the sub-core may have a smaller density than the three-dimensional core structure. Optionally, one of the plurality of cores may include a shield forming a leading edge. Alternatively, the shield, sub-core and at least one pin may each be disposed in a single common core of the inner support structure.

[0119] In another exemplary embodiment, the airfoil assembly may include an airfoil defining an airfoil interior as described above and a dovetail defining an interior of the dovetail. The airfoil assembly may include an inner support structure having a plurality of cores covered with a laminate covering as described above. At least one of the plurality of cores may be positioned individually within the airfoil interior, individually within the dovetail interior, or positioned within both the airfoil interior and the dovetail interior. At least one of the plurality of cores may be formed with a composite core material as described above. The inner support structure may include at least one pin connecting the two cores together. At least one pin may include a composite pin material. Alternatively, at least one pin may include a pin core having a composite covering as described above. Alternatively, at least one of the two cores connected by at least one pin may be formed with interwoven fibers defining a three-dimensional core structure as described above.

[0120] The described aspects of the present disclosure provide a variety of benefits. The use of composite materials provides a lighter airfoil assembly compared to a non-composite (e.g., cast) airfoil assembly without sacrificing the performance of the airfoil assembly. In other words, the material used for the composite airfoil assembly is lighter than the material used for the non-composite airfoil assembly and does not sacrifice the ability to perform as intended within the turbine engine. The reduced weight of the airfoil assembly, in turn, means an increase in the efficiency of the turbine engine when compared to a conventional turbine engine including a non-composite airfoil assembly.

[0121] Another benefit is that the use of multiple cores formed with interwoven fibers in a three-dimensional architecture can provide improved durability and material strength in multiple stress and strain directions during operation. Multiple cores also provide a flexible, re-arrangeable internal support structure suitable for various blade architectures, which reduces assembly time and improves processing efficiency during production.

[0122] Another benefit is that the use of a lighter sub-core provides a lighter airfoil assembly with additional engine efficiency and performance benefits compared to the surrounding composite material in a three-dimensional core structure. The lightweight sub-core also provides for the local inclusion of other strengthening components (such as shields as described above) in the airfoil assembly while maintaining an overall reduced weight in the airfoil assembly compared to conventional turbine engine airfoil assemblies.

[0123] Yet another benefit is that the use of fiber material pins to connect multiple cores in the inner support structure provides design flexibility and reduces production and assembly time, including by forming flange pins with a predetermined insertion depth into each core. In addition, the use of pins with a pin core and a fiber coating provides additional component durability, such as with a metal pin core, while maintaining a reduced weight compared to a conventional pin. The fiber coating provides additional insulation or material protection, such as preventing oxidation, corrosion or other material reactions of the inner support structure core or the pin core, including preventing material reactions that may occur between the inner support structure core and the pin core.

[0124] To the extent not yet described, the different features and structures of the various embodiments may be used in combination as desired, or may be interchanged with one another. Not showing a feature in all embodiments does not mean that it is interpreted as not being able to be shown in this way, but rather is done for the sake of brevity of description. Therefore, the various features of the different embodiments may be mixed and matched as desired to form new embodiments, whether or not the new embodiments are explicitly described. All combinations or permutations of the features described herein are covered by the present disclosure.

[0125] This written description uses examples to describe the aspects of the disclosure described herein, including the best mode, and also to enable any person skilled in the art to practice aspects of the disclosure, including making and using any device or system and performing any combined methods. The patentable scope of aspects of the disclosure is defined by the claims, and may include other examples that occur to one skilled in the art. These other examples are intended to fall within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements that do not differ substantially from the literal language of the claims.

[0126] Further aspects are provided by the subject matter of the following clauses:

[0127] A composite airfoil assembly for a turbine engine, comprising: an airfoil defining an airfoil interior and having an exterior surface extending axially between a leading edge and a trailing edge and radially between a root and a tip; a dovetail extending from the root and defining the dovetail interior; an inner support structure at least partially located within the airfoil interior and comprising a plurality of cores, wherein each of the plurality of cores comprises interwoven fibers defining a three-dimensional core structure; and a laminate cover surrounding at least a portion of the inner support structure and at least partially defining the exterior surface.

[0128] A composite airfoil assembly for a turbine engine, comprising: an airfoil defining an airfoil interior and having an exterior surface extending axially between a leading edge and a trailing edge and radially between a root and a tip; an inner support structure at least partially located within the airfoil interior and comprising a radially aligned first core and a second core, wherein each of the first core and the second core comprises interwoven fibers defining a three-dimensional core structure; and a laminate cover surrounding at least a portion of the inner support structure.

[0129] A composite airfoil assembly for a turbine engine, comprising: an airfoil defining an airfoil interior and having an exterior surface extending axially between a leading edge and a trailing edge and radially between a root and a tip; a dovetail extending from the root and defining the dovetail interior; an inner support structure comprising: a first core and a second core, each of the first core and the second core comprising a composite core material, wherein at least one of the first core or the second core is at least partially positioned within at least one of the airfoil interior or the dovetail interior; and at least one pin extending between the first core and the second core and connecting the first core to the second core and comprising a fiber pin material; and a laminate covering surrounding at least a portion of the inner support structure and at least partially defining the exterior surface.

[0130] A composite airfoil assembly for a turbine engine, comprising: an airfoil defining an airfoil interior and having an exterior surface, the exterior surface extending axially between a leading edge and a trailing edge and radially between a root and a tip; an inner support structure at least partially located within the airfoil interior, the inner support structure comprising a first core and a second core and at least one pin, the first core and the second core each comprising a composite core material, the at least one pin extending between the first core and the second core and connecting the first core to the second core, the at least one pin comprising a pin core having a fiber wrap; and a laminate covering surrounding at least a portion of the inner support structure and at least partially defining the exterior surface.

[0131] A composite airfoil assembly as recited in any preceding clause, wherein the plurality of cores comprises a first core and a second core at least radially spaced apart from the first core.

[0132] A composite airfoil assembly as recited in any preceding clause, wherein the plurality of cores further comprises a third core at least one of axially arranged or radially arranged relative to the second core.

[0133] A composite airfoil assembly as described in any preceding clause, wherein the third core is located radially outward from the second core and at least partially defines a tip end of the composite airfoil assembly.

[0134] A composite airfoil assembly as recited in any preceding clause, further comprising a local separation distance defined between two cores of said plurality of cores, wherein said local separation distance is at least partially filled by said laminate cover.

[0135] A composite airfoil assembly as in any preceding clause, wherein one core of the plurality of cores is positioned at least partially within the airfoil interior and another core of the plurality of cores is positioned at least partially within the dovetail interior.

[0136] A composite airfoil assembly as recited in any preceding clause, wherein the inner support structure comprises a first core defining a first width and a second core defining a second width less than the first width.

[0137] A composite airfoil assembly according to any preceding clause, wherein the interwoven fibers include at least one of woven fibers, plaited fibers, twisted fibers, knitted fibers, yarns, tows, or strands, and wherein the laminate cover includes a plurality of plies formed from at least one of pre-impregnated fibers in a polymer matrix, automated fiber placement, dry fiber placement, or custom fiber placement.

[0138] A composite airfoil assembly as described in any preceding clause, wherein a core of said plurality of cores comprises a foam sub-core surrounded by said three-dimensional core structure defined by said interwoven fibers.

[0139] A composite airfoil assembly as described in any preceding clause, wherein the density of the laminate cover is greater than the density of the three-dimensional core structure.

[0140] A composite airfoil assembly as recited in any preceding clause, further comprising a dovetail extending from the root and defining a dovetail interior, wherein the first core is at least partially positioned within the dovetail interior and the second core is at least partially positioned within the airfoil interior.

[0141] A composite airfoil assembly as recited in any preceding clause, wherein the inner support structure further comprises a third core at least one of axially arranged or radially arranged with the second core.

[0142] A composite airfoil assembly as described in any preceding clause, wherein the third core is located radially outward from the second core.

[0143] A composite airfoil assembly as described in any preceding clause, wherein the third core at least partially defines a tip end of the composite airfoil assembly.

[0144] The composite airfoil assembly of any preceding clause, further comprising a local separation distance defined between two of the first core, the second core, or the third core, wherein the local separation distance is at least partially filled by the laminate cover.

[0145] A composite airfoil assembly according to any preceding clause, wherein the interwoven fibers include at least one of woven fibers, plaited fibers, twisted fibers, knitted fibers, yarns, tows, or strands, and wherein the laminate cover includes a plurality of plies formed from at least one of pre-impregnated fibers in a polymer matrix, automated fiber placement, dry fiber placement, or custom fiber placement.

[0146] A composite airfoil assembly as described in any preceding clause, wherein at least one of the first core or the second core comprises a foam sub-core surrounded by the three-dimensional core structure.

[0147] A composite airfoil assembly as described in any preceding clause, wherein the density of the three-dimensional core structure is greater than the density of the foam sub-core.

[0148] A composite airfoil assembly as described in any preceding clause, wherein the density of the laminate cover is greater than the density of the three-dimensional core structure.

[0149] A composite airfoil assembly as described in any preceding clause, further comprising a shield covering a portion of the laminate cover and defining the leading edge.

[0150] A composite airfoil assembly as described in any preceding clause, wherein the at least one pin defines a local separation distance between the first core and the second core.

[0151] A composite airfoil assembly as described in any preceding clause, wherein the local standoff distance is at least partially filled by the laminate cover.

[0152] A composite airfoil assembly as described in any preceding clause, wherein the fiber pin material comprises at least one of fiberglass or a fiber composite material.

[0153] A composite airfoil assembly as in any preceding clause, wherein the at least one pin further comprises a body extending between a first end and a second end and a flange extending from the body to define an insertion depth into at least one of the first core or the second core.

[0154] A composite airfoil assembly as described in any preceding clause, wherein the flange is spaced apart from the first end and the second end.

[0155] A composite airfoil assembly as described in any preceding clause, wherein at least a portion of the body defines a width that increases from the first end toward the second end.

[0156] A composite airfoil assembly as described in any preceding clause, wherein at least one of the first core or the second core comprises a sub-core.

[0157] A composite airfoil assembly as described in any preceding clause, wherein the at least one pin extends into the sub-core.

[0158] A composite airfoil assembly as described in any preceding clause, wherein the sub-core comprises a foam material.

[0159] A composite airfoil assembly as described in any preceding clause, wherein the at least one pin comprises a first pin extending at least radially between the first core and the second core.

[0160] A composite airfoil assembly as described in any preceding clause, wherein the at least one pin further comprises a second pin extending within at least the second core and misaligned with the first pin.

[0161] A composite airfoil assembly as recited in any preceding clause, wherein the inner support structure further comprises a third core, wherein the at least one pin extends between and connects the first, second and third cores.

[0162] A composite airfoil assembly as claimed in any preceding clause, wherein the fiber wrap comprises glass fibers wrapped around the pin core.

[0163] A composite airfoil assembly as in any preceding clause, wherein the at least one pin further comprises a body extending between a first end and a second end and a flange extending from the body to define an insertion depth into at least one of the first core or the second core.

[0164] A composite airfoil assembly as described in any preceding clause, wherein the flange is spaced apart from each of the first end and the second end.

[0165] A composite airfoil assembly as described in any preceding clause, wherein at least a portion of the body defines a width that increases from the first end toward the second end.

[0166] A composite airfoil assembly as described in any preceding clause, wherein at least one of the first core or the second core comprises a sub-core.

[0167] A composite airfoil assembly as described in any preceding clause, wherein the sub-core comprises a foam material.

[0168] A composite airfoil assembly as described in any preceding clause, wherein the at least one pin extends into the sub-core.

[0169] A composite airfoil assembly as described in any preceding clause, wherein the at least one pin comprises a first pin extending at least radially between the first core and the second core.

[0170] A composite airfoil assembly as described in any preceding clause, wherein the at least one pin further comprises a second pin extending within at least the second core and misaligned with the first pin.

[0171] A composite airfoil assembly as described in any preceding clause, wherein the composite airfoil assembly comprises composite blades configured to rotate within the turbine engine at a speed between 1000-2500 RPM.

[0172] A composite airfoil assembly as described in any preceding clause, wherein the exterior surface of the airfoil defines a pressure side opposite a suction side.

[0173] A composite airfoil assembly as described in any preceding clause, wherein the exterior surface of the airfoil defines a symmetrical airfoil profile.

[0174] A composite airfoil assembly as described in any preceding clause, wherein the first core is at least partially positioned within the dovetail interior.

[0175] A composite airfoil assembly as described in any preceding clause, wherein the shield comprises a metallic material.

[0176] A composite airfoil assembly according to any preceding clause, wherein the inner support structure further comprises a third core, wherein the at least one pin extends between and connects at least two of the first core, the second core, and the third core.

[0177] A composite airfoil assembly as described in any preceding clause, wherein the fiber pin material comprises at least one of a glass fiber or a composite fiber material.

[0178] A composite airfoil assembly as described in any preceding clause, wherein the fiber wrap comprises fibers at least one of helically wound or braided about the pin core.

[0179] A method of forming a composite airfoil assembly includes: forming an inner support structure having at least a first core and a second core, the first core and the second core each having a core material having at least one of fibers, yarns, braids, or tows; and applying a laminate cover to surround at least a portion of the inner support structure.

[0180] A method as in any preceding clause, wherein forming the inner support structure comprises interweaving the core material to define a three-dimensional core structure of at least one of the first core or the second core.

[0181] A method as in any preceding clause, wherein forming the inner support structure comprises weaving the core material by a three-dimensional weaving process to define a three-dimensional core structure of at least one of the first core or the second core.

[0182] A method as in any preceding clause, wherein forming the inner support structure comprises weaving three sets of core materials along corresponding three different directions to define a three-dimensional braided core structure of at least one of the first core or the second core.

[0183] A method as in any preceding clause, wherein forming the inner support structure comprises forming at least one of the first core or the second core around a sub-core.

[0184] The method of any preceding clause, wherein forming the inner support structure comprises positioning at least one of the first core or the second core to at least partially form a dovetail, root, or tip of the composite airfoil assembly.

[0185] A method as in any preceding clause, wherein forming the inner support structure comprises inserting at least one pin into the first core and the second core, thereby connecting the first core to the second core.

[0186] A method as in any preceding clause, wherein forming the inner support structure comprises defining a separation distance between the first core and the second core via the at least one pin.

[0187] A method as in any preceding clause, wherein forming the inner support structure comprises inserting the at least one pin into a sub-core within at least one of the first core or the second core.

[0188] A method as in any preceding clause, wherein forming the inner support structure comprises forming a composite pin by applying a composite material to a metal pin core.

[0189] A method as in any preceding clause, wherein applying the laminate covering comprises applying a plurality of stacked plies on the inner support structure.

[0190] A method as in any preceding clause, wherein applying the laminate cover comprises forming an exterior surface of the composite airfoil assembly.

[0191] A method as in any preceding clause, wherein applying the laminate covering comprises at least partially filling a separation distance between the first core and the second core with the laminate covering.

[0192] A method as in any preceding clause, further comprising at least partially filling a separation distance between the first core and the second core with a resin material.

[0193] A method as in any preceding clause, wherein applying the laminate covering comprises covering the resin material with the laminate covering.

Claims

1. A composite airfoil assembly for a turbine engine, characterized in that: include: an airfoil defining an airfoil interior and having an exterior surface extending axially between a leading edge and a trailing edge and radially between a root and a tip; a dovetail extending from the root and defining a dovetail interior; an inner support structure at least partially located within the airfoil interior and comprising a plurality of cores, wherein each core of the plurality of cores comprises interwoven fibers defining a three-dimensional core structure, the plurality of cores having a first core and a second core spaced apart from the first core; a laminate covering surrounding at least a portion of the inner support structure and at least partially defining the exterior surface; as well as A pin is located within the airfoil interior, the pin extending into and between each of the first and second cores.

2. The composite airfoil assembly according to claim 1, wherein: in, The second core is at least radially spaced from the first core.

3. The composite airfoil assembly according to claim 2, wherein: in, The plurality of cores further includes a third core at least one of axially arranged or radially arranged relative to the second core.

4. The composite airfoil assembly according to claim 3, wherein: in, The third core is positioned radially outward from the second core and at least partially defines a tip end of the composite airfoil assembly.

5. The composite airfoil assembly of claim 1, wherein: Further comprising defining a local separation distance between two cores of the plurality of cores, wherein the local separation distance is at least partially filled by the laminate cover.

6. The composite airfoil assembly of claim 1, wherein: in, One core of the plurality of cores is at least partially positioned within the airfoil interior, and another core of the plurality of cores is at least partially positioned within the dovetail interior.

7. The composite airfoil assembly of claim 1, wherein: in, The inner support structure includes a first core defining a first width and a second core defining a second width that is less than the first width.

8. The composite airfoil assembly of claim 1, wherein: in, The interwoven fibers include at least one of woven fibers, plaited fibers, twisted fibers, knitted fibers, yarns, tows, or single strands, and wherein the laminate covering includes a plurality of plies formed from at least one of pre-impregnated fibers in a polymer matrix, automated fiber placement, dry fiber placement, or custom fiber placement.

9. The composite airfoil assembly of claim 1, wherein: in, A core of the plurality of cores includes a foam sub-core surrounded by the three-dimensional core structure defined by the interwoven fibers.

10. The composite airfoil assembly of claim 1, wherein: in, The density of the laminate cover is greater than the density of the three-dimensional core structure.

11. The composite airfoil assembly of claim 1, wherein: Further included is a shield covering a portion of the laminate cover and defining the leading edge.

12. A composite airfoil assembly for a turbine engine, characterized in that: include: an airfoil defining an airfoil interior and having an exterior surface extending axially between a leading edge and a trailing edge and radially between a root and a tip; an inner support structure located at least partially within the airfoil interior and comprising a radially aligned first core and a second core, wherein each of the first core and the second core comprises interwoven fibers defining a three-dimensional core structure; a laminate covering surrounding at least a portion of the inner support structure; as well as A pin is located within the airfoil interior, the pin extending into and between each of the first and second cores.

13. The composite airfoil assembly of claim 12, wherein: Further included is a dovetail extending from the root and defining a dovetail interior, wherein the first core is at least partially positioned within the dovetail interior and the second core is at least partially positioned within the airfoil interior.

14. The composite airfoil assembly of claim 12, wherein: in, The inner support structure further includes a third core at least one of axially arranged or radially arranged with the second core.

15. The composite airfoil assembly of claim 14, wherein: in, The third core is positioned radially outward from the second core and at least partially defines a tip end of the composite airfoil assembly.

16. The composite airfoil assembly of claim 14, wherein: Further comprising defining a local separation distance between two cores among the first core, the second core, or the third core, wherein the local separation distance is at least partially filled by the laminate cover.

17. The composite airfoil assembly of claim 12, wherein: in, The interwoven fibers include at least one of woven fibers, plaited fibers, twisted fibers, knitted fibers, yarns, tows, or single strands, and wherein the laminate covering includes a plurality of plies formed from at least one of pre-impregnated fibers in a polymer matrix, automated fiber placement, dry fiber placement, or custom fiber placement.

18. The composite airfoil assembly of claim 12, wherein: in, At least one of the first core or the second core includes a foam sub-core surrounded by the three-dimensional core structure.

19. The composite airfoil assembly of claim 12, wherein: in, The density of the laminate cover is greater than the density of the three-dimensional core structure.

20. The composite airfoil assembly of claim 12, wherein: Further included is a shield covering a portion of the laminate cover and defining the leading edge.

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