Composite airfoil

Abstract

A composite airfoil includes an airfoil portion and a composite ply. The airfoil portion has an outer wall extending between the root and the tip and between the leading edge and the trailing edge. The composite layup has a first set of fibers and a second set of fibers. Each fiber in the first set of fibers is along a first centerline axis. Each fiber in the second set of fibers extends along a second centerline axis.

Description

TECHNICAL FIELD

[0001] The present disclosure generally relates to airfoils and, more particularly, to composite airfoils having composite layups. BACKGROUND OF THE INVENTION

[0002] A turbine engine (and particularly a gas or combustion turbine engine) is a rotary engine that extracts energy from a gas stream that passes through a fan having a plurality of fan blades and then through a series of compressor stages (which include pairs of rotating blades and stationary vanes), through a combustor, and then through a series of turbine stages (which include pairs of rotating blades and stationary vanes) into the engine. The blades are mounted to a rotating disk, while the vanes are mounted to a stator disk.

[0003] Some components of a turbine engine may include composite materials. Composite materials generally include a fiber-reinforced matrix and exhibit a high strength-to-weight ratio. Due to the high strength-to-weight ratio and formability to adopt relatively complex shapes, composite materials are used in various applications such as turbine engines or aircraft. For example, composite materials can be mounted on or define a part of a fuselage or wing, rudder, manifold, airfoil, or other components of an aircraft or turbine engine. BRIEF DESCRIPTION OF THE DRAWINGS

[0004] A complete 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, which makes reference to the accompanying drawings, in which:

[0005] Figure 1 is a schematic cross-sectional view of a turbine engine in accordance with an exemplary embodiment of the present disclosure.

[0006] Figure 2 is a schematic perspective view of a component adapted to be used within a Figure 1 turbine engine and including a rotatable disk and a composite airfoil having a first region and a second region.

[0007] Figure 3 is Figure 2 a schematic plan view of the first region of

[0008] Figure 4 is Figure 2 a schematic plan view of the second region of

[0009] Figure 5 is Figure 1 a schematic side view of an exemplary component adapted to be used within a turbine engine and including a spar and trunnions.

[0010] Aspects disclosed herein relate to a composite airfoil including one or more composite plies. The composite plies include one or more tows. As used herein, a tow refers to a continuous filament or bundle of fibers, where each fiber in the tow has its own centerline axis and extends along its own centerline axis. The composite ply may include, for example, a first tow and a second tow intertwined with the first tow. The first tow and the second tow may have different bulk moduli. For illustrative purposes, the present disclosure will be described with respect to a composite airfoil disposed within a turbine engine. However, it should be understood that the disclosed aspects herein are not limited thereto and may have general applicability within other engines or other parts of a turbine engine. For example, the present disclosure may be applicable to rotatable disks, seal boxes, and blades in other engines or vehicles and may be used to provide benefits in industrial, commercial, and residential applications.

[0011] As used herein, the term "upstream" refers to the direction opposite to the fluid flow direction, while the term "downstream" refers to the direction the same as the fluid flow direction. The terms "front" or "forward" indicate in front of something, and "rear" or "backward" indicate behind something. For example, when used in the context of fluid flow, front / forward may indicate upstream, and rear / backward may indicate downstream.

[0012] Furthermore, as used herein, the term "radial" or "radially" refers to the direction away from a common center. For example, in the overall context of a turbine engine, radial refers to the direction along a ray extending between the central longitudinal axis of the engine and the outer periphery of the engine. Additionally, as used herein, the term "group" or a "group" of elements may be any number of elements, including only one.

[0013] As used herein, the term "bulk modulus" refers to a measure of the ability of a substance to withstand a change in volume when compressed on all sides. The bulk modulus is a function of the initial volume of the substance and is the derivative of pressure with respect to volume.

[0014] Moreover, as used herein, the term "fluid" or its iterations may refer to any suitable fluid within a gas turbine engine, where at least a portion of the gas turbine engine is exposed to, for example but not limited to, combustion gases, ambient air, pressurized airflows, working airflows, or any combination thereof. It is further contemplated that the gas turbine engine may be other suitable turbine engines, such as but not limited to steam turbine engines or supercritical carbon dioxide turbine engines. As a non-limiting example, the term "fluid" may refer to steam in a steam turbine engine or carbon dioxide in a supercritical carbon dioxide turbine engine.

[0015] 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 for identification purposes only to assist the reader in understanding the present disclosure and do not impose limitations, particularly as to the position, orientation, or use of aspects of the disclosure described herein. Connecting references (e.g., attach, couple, fix, fasten, connect, and join) are to be construed broadly and may include intermediate members between elements and relative movement between elements, unless otherwise indicated. Thus, a connecting reference does not necessarily imply that the two elements are directly connected and fixed relative to each other. Exemplary drawings are for illustrative purposes only, and the dimensions, positions, sequences, and relative sizes reflected in the accompanying drawings may vary.

[0016] As used herein, the term "composite" means 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 metallic and non-metallic 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 fiber, polymeric resin, thermoplastic resin, bismaleimide (BMI) materials, polyimide materials, epoxy resin, glass fiber, and silicon matrix materials.

[0017] As used herein, a "composite" component refers to a structure or component that includes any suitable composite material. A composite component (e.g., a composite airfoil) can include several layers or plies of composite material. The stiffness, material, and dimensions of the layers or plies can vary to achieve a desired composite component or composite portion of a component having a predetermined weight, size, stiffness, and strength.

[0018] One or more layers of adhesive can be used to form or join composite components. The adhesive can include resin and phenolic resin, where the adhesive may require curing at elevated temperatures or other hardening techniques.

[0019] As used herein, PMC refers to a class of materials. As an example, PMC materials are partially defined by prepregs, which are reinforcing materials pre-impregnated with a polymer matrix material (e.g., a thermoplastic resin). Non-limiting examples of processes for producing thermoplastic prepregs include: hot melt prepreg methods, where a fiber reinforcement is pulled through a melt bath of resin; and powder impregnation methods, where resin is deposited onto the fiber reinforcement, as a non-limiting example, electrostatically deposited onto the fiber reinforcement and then adhered to the fiber, as a non-limiting example, in an oven or with the aid of heated rollers. The 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 for the part.

[0020] Multiple prepregs are stacked to the appropriate thickness and orientation of the composite part, and then the resin is cured and solidified to provide a fiber-reinforced composite part. Resins used for PMC matrix materials can generally be classified as thermosetting resins or thermoplastic resins. Thermoplastic resins are generally classified as polymers that can be repeatedly softened and flowed when heated and hardened due to physical changes rather than chemical changes when sufficiently cooled. Well-known example categories of thermoplastic resins include nylon, thermoplastic polyester, polyaryletherketone, and polycarbonate resins. Specific examples of high-performance thermoplastic resins envisioned for aerospace applications include polyetheretherketone (PEEK), polyetherketoneketone (PEKK), polyetherimide (PEI), polyaryletherketone (PAEK), and polyphenylene sulfide (PPS). In contrast, once fully cured into a hard and rigid solid, thermosetting resins do not undergo significant softening when heated but instead thermally decompose when sufficiently heated. Well-known examples of thermosetting resins include epoxy resins, bismaleimide (BMI), and polyimide resins.

[0021] Instead of using prepregs, in another non-limiting example, by using a thermoplastic polymer, a woven fabric can be utilized. The woven fabric can include, but is not limited to, dry carbon fibers woven together with thermoplastic polymer fibers or filaments. A non-prepreg braided architecture can be made in a similar manner. By this method, the fiber volume of the part can be customized by specifying the relative concentrations of the thermoplastic fibers and the reinforcing fibers that have been braided or woven together. Additionally, different types of reinforcing fibers can be braided or woven together at different concentrations to customize the properties of the part. For example, glass fibers, carbon fibers, and thermoplastic fibers can all be woven together at different concentrations to customize the properties of the part. Carbon fibers provide the strength of the system and can be incorporated with glass fibers to enhance impact properties, which is a design feature of parts located near the engine inlet, and thermoplastic fibers provide bonding for the reinforcing fibers.

[0022] In yet another non-limiting example, resin transfer molding (RTM) can be used to form at least a portion of the composite part. Generally, RTM involves applying dry fibers or matrix materials to a mold or cavity. The dry fibers or matrix materials can include prepregs, braided materials, woven materials, or any combination thereof.

[0023] The resin can be pumped or otherwise provided to the mold or cavity to impregnate the dry fibers or matrix materials. The combination of the impregnated fibers or matrix materials and the resin is then cured and removed from the mold. When removed from the mold, the composite part may require a post-curing treatment.

[0024] It is contemplated that the RTM can be a vacuum assisted process. That is, prior to heating or curing, the air in the cavity or mold can be removed and replaced with resin. It is further contemplated that the placement of the dry fibers or matrix materials can be manual or automated.

[0025] The dry fibers or matrix materials can be shaped to form a composite part or to direct the resin. Optionally, additional layers or reinforcement layers of materials different from the dry fibers or matrix materials can also be included or added prior to heating or curing.

[0026] As used herein, CMC refers to a class of materials having reinforcing fibers in a ceramic matrix. Generally, the reinforcing fibers provide structural integrity to the ceramic matrix. Some examples of the reinforcing fibers can 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 (Al 2 O 3 ), silicon dioxide (SiO 2 ), aluminosilicates such as mullite, or mixtures thereof), or mixtures thereof.

[0027] Some examples of the ceramic matrix materials can 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 (Al 2 O 3 ), silicon dioxide (SiO 2 ), 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) can also be included within the ceramic matrix.

[0028] Generally, specific CMCs can be referred to by the combination of their fiber type / matrix type. 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, the CMC can be composed of a matrix containing oxide-based materials such as aluminum oxide (Al 2 O 3 ), silicon dioxide (SiO 2 ), aluminosilicates and mixtures thereof) and reinforcing fibers. The aluminosilicate can include crystalline materials (e.g., mullite (3Al 2 O 3 ·2SiO 2 )) and vitreous aluminosilicates.

[0029] In certain non-limiting examples, the reinforcing fibers can be bundled and / or coated before being incorporated into the matrix. For example, fiber bundles can be formed into reinforcing tapes, such as unidirectional reinforcing tapes. Multiple tapes can be stacked together to form a preform component. The fiber bundles can be impregnated with a slurry composition either before or after forming the preform. The preform can then be heat treated and subsequently chemically treated to obtain a component formed of a CMC material having a desired chemical composition. For example, the preform can be cured or burned out to produce a high coke residue in the preform, and subsequently melt infiltrated with silicon, or cured or pyrolyzed to produce a silicon carbide matrix in the preform, and subsequently chemically vapor infiltrated with silicon carbide. Additional steps can be taken to increase the densification of the preform, either before or after chemical vapor infiltration, by injecting a liquid resin or polymer into the preform and then performing a heat treatment step to fill the voids with silicon carbide. The CMC materials used herein can be formed using any known or later developed method (including but not limited to melt infiltration, chemical vapor infiltration, polymer impregnation pyrolysis (PIP), or any combination thereof).

[0030] Such materials, along with certain monolithic ceramics (i.e., ceramic materials without reinforcing materials), are particularly suitable for higher temperature applications. In addition, these ceramic materials are lightweight compared to superalloys but still provide strength and durability to the components made from them. Accordingly, such materials are currently being considered for use in many gas turbine components (such as airfoils (e.g., turbines and vanes), burners, shrouds, etc.) used in the higher temperature sections of gas turbine engines, which would benefit from the lighter weight and higher temperature capabilities that these materials can provide.

[0031] As used herein, the term "metal" refers to materials that include metals (such as but not limited to titanium, iron, aluminum, stainless steel, and nickel alloys). A metallic material or alloy can be a combination of at least two or more elements or materials, where at least one is a metal.

[0032] 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 that extends from a front portion 14 to a rear portion 16. The turbine engine 10 includes, in a downstream serial flow relationship: a fan section 18 that includes a fan 20; a compressor section 22 that includes a booster or low pressure (LP) compressor 24 and a high pressure (HP) compressor 26; a combustion section 28 that includes a burner 30; a turbine section 32 that includes an HP turbine 34 and an LP turbine 36; and an exhaust section 38.

[0033] The fan section 18 includes a fan casing 40 that surrounds a fan 20. The fan 20 includes a plurality of fan blades 42 that are radially disposed about the engine centerline 12. The HP compressor 26, the combustor 30, and the HP turbine 34 form an engine core 44 of the turbine engine 10, which generates combustion gases. The engine core 44 is surrounded by a core casing 46, which may be coupled to the fan casing 40.

[0034] The HP shaft 48 is coaxially disposed about the engine centerline 12 of the turbine engine 10 and drivingly connects the HP turbine 34 to the HP compressor 26. An LP shaft 50, which is coaxially disposed about the engine centerline 12 within the larger diameter annular HP shaft 48, drivingly connects the LP turbine 36 to the LP compressor 24 and the fan 20. The shafts 48, 50 are rotatable about the engine centerline 12 and are coupled to a plurality of rotatable elements, which may collectively define a rotor 51.

[0035] The LP compressor 24 and the HP compressor 26 each include a plurality of compressor stages 52, 54, where a set of compressor blades 56, 58 rotates relative to a corresponding set of stationary compressor vanes 60, 62 to compress or pressurize the fluid flow passing 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 tip relative to the engine centerline 12, while the corresponding stationary compressor vanes 60, 62 are positioned upstream and adjacent to the rotating compressor blades 56, 58. It is noted that Figure 1 the number of blades, vanes, and compressor stages shown is only selected for illustrative purposes, and other numbers are possible.

[0036] The compressor blades 56, 58 for one stage of the compressors 24, 26 may be mounted to (or integrated with) a disk 61, which is mounted to the corresponding one of the HP and LP shafts 48, 50. The stationary compressor vanes 60, 62 for one stage of the compressors 24, 26 may be mounted to the core casing 46 in a circumferential arrangement.

[0037] The HP turbine 34 and the LP turbine 36 each include a plurality of turbine stages 64, 66, where a set of turbine blades 68, 70 rotates relative to a corresponding set of stationary turbine vanes 72, 74 (also referred to as nozzles) to extract energy from the 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 stationary turbine vanes 72, 74 are positioned upstream and adjacent to the rotating turbine blades 68, 70. It is noted that Figure 1 the number of blades, vanes, and turbine stages shown is only selected for illustrative purposes, and other numbers are possible.

[0038] The turbine blades 68, 70 for the first stage of the turbine can be mounted to a disk 71, which is mounted to the corresponding one of the HP and LP shafts 48, 50. The turbine vanes 72, 74 for the first stage of the compressor can be mounted circumferentially to the core housing 46.

[0039] Complementary to the rotor section, the stationary section of the turbine engine 10 (e.g., the stationary vanes 60, 62, 72, 74 in the compressor section 22 and the turbine section 32) is also referred to individually or collectively as the stator 63. Thus, the stator 63 can refer to the combination of non-rotating elements throughout the turbine engine 10.

[0040] It should be understood that the turbine engine 10 can be divided into at least two separate parts: a rotor section and a stator section. The rotor section can be defined as any part of the turbine engine 10 that rotates about a corresponding axis of rotation. The stator section can be defined by the combination of non-rotating elements disposed within the turbine engine 10. As a non-limiting example, the rotor section can include one or more of the plurality of fan blades 42, compressor blades 56, 58, or turbine blades 68, 70. As a non-limiting example, the stator section can include one or more of the plurality of airfoil guide vanes 82 (described below), stationary compressor vanes 60, 62, or stationary turbine vanes 72, 74.

[0041] In operation, the airflow leaving the fan section 18 is split such that a portion of the airflow is directed into the LP compressor 24, which then supplies a 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 fuel in the combustor 30 and ignited, thereby generating combustion gases. The HP turbine 34 extracts some work from these gases, and the HP turbine 34 drives the HP compressor 26. The combustion gases are discharged into the LP turbine 36, which extracts additional work to drive the LP compressor 24, and the exhaust is finally discharged from the turbine engine 10 via the exhaust section 38. The driving of the LP turbine 36 drives the LP shaft 50 to rotate the fan 20 and the LP compressor 24.

[0042] A portion of the pressurized airflow 76 can be extracted as bleed air 77 from the compressor section 22. The bleed air 77 can be extracted from the pressurized airflow 76 and provided to engine components for cooling. The temperature of the pressurized airflow 76 entering the combustor 30 is significantly increased to be higher than the bleed air temperature. The bleed air 77 can be used to reduce the temperature of the core components downstream of the combustor 30. The bleed air 77 can also be utilized by other systems.

[0043] Some of the air supplied by fan 20 can 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 burner 30, particularly in the turbine section 32, where the HP turbine 34 is the hottest portion as it is directly downstream of the combustion section 28. Other sources of cooling fluid can be, but are not limited to, fluid bled from the LP compressor 24 or the HP compressor 26.

[0044] The airflow that remains after leaving the remainder of the fan section 18 (referred to as the 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 is used adjacent the fan section 18 to exert at least some directional control on the bypass airflow 78.

[0045] As shown, the turbine engine 10 is a turbofan engine. However, it should be understood that the turbine engine 10 can be any suitable engine, such as but not limited to a turboprop engine, a turboshaft engine, a ducted turbofan engine, a non-ducted engine, or an open rotor turbine engine. As a non-limiting example, the turbine engine 10 can be a non-ducted turbine engine. A non-ducted turbine engine includes a set of external fan blades and external fan vanes that extend radially outward from a nacelle or outer casing that houses the engine core. The external fan blades and external fan vanes are functionally similar to the fan blades 42 and the airfoil guide vanes 82 of the turbine engine 10, respectively. It should be understood that at least a portion of the external fan blades or external fan vanes can define a radial extreme (e.g., the portion that is radially furthest from the engine centerline 12) in a non-ducted turbine engine. In other words, in a non-ducted turbine engine, no portion of the turbine engine is disposed radially outside of the external fan blades or external fan vanes.

[0046] Figure 2 is suitable for use within Figure 1 the turbine engine 10 and is a schematic perspective view of an assembly 100 including a rotatable disk 102 and a composite airfoil 104. The rotatable disk 102 is suitable for use as the rotatable disk 61, 71 ( Figure 1 ) or any other disk, such as but not limited to a disk within the fan section 18 ( Figure 1 ) of the turbine engine 10 ( Figure 1 ). The rotatable disk 102 is rotatable about a rotational axis 106, which can be aligned with the engine centerline (e.g., Figure 1coincide with or deviate from the engine centerline 12).

[0047] The rotatable disk 102 includes a front surface 130 and a rear surface 132, wherein an outer peripheral surface 134 interconnects the front surface 130 and the rear surface 132. A plurality of slots 108 axially extend along the outer peripheral surface 134 between the front surface 130 and the rear surface 132. Each of the plurality of slots 108 extends radially inward from the outer peripheral surface 134 toward the axis of rotation 106. The total circumferential distance that each of the plurality of slots 108 extends is less than the total axial distance that the slots extend along the outer peripheral surface 134.

[0048] The composite airfoil 104 includes an airfoil portion 110 and a dovetail portion 112 extending from the airfoil portion 110. For illustrative purposes, the transition 126 between the dovetail portion 112 and the airfoil portion 110 is shown in dashed lines. The dovetail portion 112 may define a portion of the composite airfoil 104 that flares circumferentially outward from the airfoil portion 110. The dovetail portion 112 defines a portion of the composite airfoil 104 that is receivable within a corresponding slot of the plurality of slots 108.

[0049] The airfoil portion 110 includes an outer wall 172. The outer wall 172 extends between a leading edge 114 and a trailing edge 116 to define a chordwise direction. The composite airfoil 104 extends between a root 118 and a tip 120 to define a spanwise direction. The dovetail portion 112 terminates radially at the root 118. The airfoil portion 110 includes a pressure side 122 and a suction side 124.

[0050] The composite airfoil 104 is coupled to the rotatable disk 102 by inserting the composite airfoil 104, particularly the dovetail portion 112, into a corresponding slot of the plurality of slots 108. Once the airfoil 104 is inserted, the airfoil portion 110 extends radially outward from the outer peripheral surface 134. The composite airfoil 104 is held in place by frictional contact with the slots 108 or may be coupled to the slots 108 via any suitable coupling method (such as but not limited to welding, bonding, fastening, etc.). Although only a single composite airfoil 104 is shown, it should be understood that there may be any number of one or more composite airfoils 104 in the assembly 100. As a non-limiting example, the total number of composite airfoils 104 may correspond to the total number of slots in the plurality of slots 108.

[0051] The composite airfoil 104 may include a composite material. As a non-limiting example, the composite airfoil 104 may at least include a PMC portion, a polymer portion, or both. The PMC may include but is not limited to a matrix of thermosetting (epoxy resin, phenolic resin) or thermoplastic (polycarbonate, polyvinyl chloride, nylon, acrylic resin) and embedded glass, carbon, steel, or a combination thereof. It should be understood that the airfoil portion 110 may include a composite material, a metallic material, any other suitable material, or a combination thereof.

[0052] The composite airfoil 104 can be divided into multiple regions. As a non-limiting example, the composite airfoil 104 can include a first region 156 and a second region 158. The first region 156 is in a region separated from the second region 158. The first region 156 and the second region 158 each include a composite material.

[0053] The composite airfoil 104 can include any number of one or more regions. The first region 156 and the second region 158 are for illustrative purposes only. As a non-limiting example, the composite airfoil 104 can include a third region. The first region 156, the second region 158, or any other region of the composite airfoil 104 can be disposed along any part of the composite airfoil 104. As a non-limiting example, the first region 156 can be disposed along the dovetail portion 112, while the second region 158 can be disposed along the airfoil portion 110. As a non-limiting example, the first region 156 can be disposed along the dovetail portion 112, while the second region 158 can be disposed along the leading edge 114. The placement of the first region 156, the second region 158, or any other region can be positioned along the thickness of the composite airfoil 104. As a non-limiting example, the first region 156 can be disposed along the outer wall 172, while the second region 158 can be disposed inside the composite airfoil 104. As a non-limiting example, the second region 158 can be covered by the first region 156. As a non-limiting example, the second region 158 can form part of a core (not shown) of the composite airfoil 104 surrounded by the outer wall 172, and the outer wall 172 can be at least partially defined by the first region 156.

[0054] Although described as the composite airfoil 104 being mounted to the rotatable disk 102, it should be understood that the composite airfoil 104 can be any suitable stationary or rotating airfoil. In the former case, the composite airfoil 104 can be mounted to a stationary body rather than the rotatable disk 102. Thus, the composite airfoil 104 can be a stationary compressor vane 60, 62 ( Figure 1 ), the set of compressor blades 56, 58 ( Figure 1 ), a stationary turbine vane 72, 74 ( Figure 1 ), the set of turbine blades 68, 70 ( Figure 1 ) or at least one of a plurality of fan blades 42. In the case where the composite airfoil 104 is mounted to a stationary component of the turbine engine 10 ( Figure 1 ), the body identified by the rotatable disk 102 can be any suitable stationary part to which the composite airfoil 104 of the turbine engine 10 ( Figure 1 ) can be coupled, such as but not limited to a band, a shroud, a housing, etc.

[0055] Figure 3 isFigure 2 Schematic plan view of the first region 156. The first region 156 includes a first composite ply 136. The first composite ply 136 may include any number of one or more tows. As a non-limiting example, the first composite ply 136 includes a first tow 140 and a second tow 142.

[0056] The first tow 140 includes a first group of fibers 160. The second tow 142 includes a second group of fibers 162. The first group of fibers 160 is interwoven (e.g., braided or woven) with the second group of fibers 162. As a non-limiting example, the fibers in the first group of fibers 160 and the second group of fibers 162 may include respective patterns in which the fibers are interwoven with the other of the first group of fibers 160 or the second group of fibers 162. Each fiber in the first group of fibers 160 includes a pattern that extends above or below the corresponding fiber in the second group of fibers 162 from right to left. As a non-limiting example, the first fiber in the first group of fibers 160 may extend above two adjacent second fibers in the second group of fibers 162, below the next second fiber in the second group of fibers 162, and above the next second fiber in the second group of fibers 162. The first group of fibers 160 and the second group of fibers 162 may include any suitable patterns, which may be the same or different between the first group of fibers 160 and the second group of fibers 162.

[0057] Each fiber in the first group of fibers 160 includes a first centerline axis 144 (only one is shown). Each fiber in the second group of fibers 162 includes a second centerline axis 146 (only one is shown). The first group of fibers 160 is angled relative to the second group of fibers 162 such that the first centerline axis 144 intersects the second centerline axis 146 at a first included angle 148. The first included angle 148 may include an absolute value greater than 0 degrees and less than 180 degrees. As a non-limiting example, the first included angle 148 may include an absolute value greater than or equal to 5 degrees and less than or equal to 60 degrees.

[0058] The first fiber bundle 140 may have a different configuration from the second fiber bundle 142. As used herein, configuration refers to at least one of a variety of fibers, the material properties of the set of fibers within a composite ply, or a combination thereof. As a non-limiting example, the first set of fibers 160 may include a first bulk modulus, and the second set of fibers 162 may include a second bulk modulus different from the first bulk modulus. As a non-limiting example, the first bulk modulus and the second bulk modulus may each differ from one another by more than 5%. A single fiber bundle of the first composite ply 136 may include different bulk moduli within the corresponding set of fibers that make up the single fiber bundle. As a non-limiting example, the second set of fibers 162 may include a first fiber 198 and a second fiber 199. The first fiber 198 may have a second bulk modulus. The second fiber 199 may have a bulk modulus not equal to the second bulk modulus. Thus, it should be understood that at least a portion of the first set of fibers 160 may include a first bulk modulus, and at least a portion of the second set of fibers 162 may include a second bulk modulus.

[0059] It should be understood that the first set of fibers 160, the second set of fibers 162, or any other number of additional sets of fibers may be disposed within a single fiber bundle. As a non-limiting example, the first set of fibers 160 includes a plurality of fibers all formed as the first fiber 198, and the second set of fibers 162 includes a plurality of fibers all formed as the second fiber 199. In other words, the first set of fibers 160 may include a plurality of fibers having a first bulk modulus, while the second set of fibers 162 may include a plurality of fibers having a second bulk modulus different from the first bulk modulus. The first set of fibers 160 may be alternately spaced relative to the second set of fibers 162 such that an alternating pattern of the first fiber 198 and the second fiber 199 is formed along the single fiber bundle. Alternatively, the first set of fibers 160 and the second set of fibers 162 may be non-alternately spaced such that pockets of two or more adjacent first fibers 198 or two or more second fibers 199 are formed in the single fiber bundle.

[0060] Figure 4 is Figure 2 A schematic plan view of a second region 158. The second region may include a second composite ply 138. The second composite ply 138 may include any number of one or more fiber bundles. As a non-limiting example, the second composite ply 138 may include a third fiber bundle 180, a fourth fiber bundle 182, and a fifth fiber bundle 184.

[0061] The third tow 180 includes a third group of fibers 186. The fourth tow 182 includes a fourth group of fibers 188. The fifth tow 184 includes a fifth group of fibers 190. The third group of fibers 186, the fourth group of fibers 188, and the fifth group of fibers 190 are intertwined with each other (e.g., woven or braided). The third group of fibers 186, the fourth group of fibers 188, and the fifth group of fibers 190 can include any suitable pattern relative to each other. Each fiber in the third group of fibers 186 extends along a third centerline axis 192. Each fiber in the fourth group of fibers 188 extends along a fourth centerline axis 194. Each fiber in the fifth group of fibers 190 extends along a fifth centerline axis 196.

[0062] The third group of fibers 186 is not parallel to the fourth group of fibers 188, such that a second included angle 181 is formed between the third centerline axis 192 and the fourth centerline axis 194. The third group of fibers 186 is not parallel to the fifth group of fibers 190, such that a third included angle 183 is formed between the third centerline axis 192 and the fifth centerline axis 196. The fifth group of fibers 190 is not parallel to the fourth group of fibers 188, such that a fourth included angle 185 is formed between the fifth centerline axis 196 and the fourth centerline axis 194. The values of the second included angle 181, the third included angle 183, and the fourth included angle 185 can all be unequal to each other. As a non-limiting example, the second included angle 181, the third included angle 183, and the fourth included angle 185 can each include an absolute value greater than 0 degrees and less than 180 degrees. As a non-limiting example, the second included angle 181, the third included angle 183, and the fourth included angle 185 can each include an absolute value greater than or equal to 5 degrees and less than or equal to 60 degrees.

[0063] The third tow 180, the fourth tow 182, and the fifth tow 184 can all have different configurations relative to each other. As a non-limiting example, the third group of fibers 186 can have a third volume modulus, the fourth group of fibers 188 can have a fourth volume modulus, and the fifth group of fibers 190 can have a fifth volume modulus. The third volume modulus, the fourth volume modulus, and the fifth volume modulus can be unequal. As a non-limiting example, the third volume modulus, the fourth volume modulus, and the fifth volume modulus can each differ from each other by more than 5%. As a non-limiting example, the first volume modulus can be greater than 1.05 times the second volume modulus or less than 0.95 times the second volume modulus. Similar to the first composite ply 136 ( Figure 3 )), individual tows of the second composite ply 138 can include different volume moduli within the respective group of fibers that make up the individual tow. Thus, it should be understood that at least a portion of the third group of fibers 186 can have a third volume modulus, at least a portion of the fourth group of fibers 188 can have a fourth volume modulus, and at least a portion of the fifth group of fibers 190 can have a fifth volume modulus.

[0064] ReferenceFigure 3 and Figure 4 , the first composite ply 136 has a different configuration from the second composite ply 138. As a non-limiting example, the first composite ply 136 can have a different number of tows, the volume modulus of the fibers, the angle of the fibers, material properties, or a combination thereof. At least a portion of the second composite ply 138 can be a continuation of the first composite ply 136. As a non-limiting example, the third tow 180 and the fourth tow 182 can be the first tow 140 and the second tow 142, respectively, but extend into the second region 158. As a non-limiting example, a different configuration can include a fifth tow 184 in the second region 158. As a non-limiting example, a different configuration can be that the volume modulus of the first tow 140 is different from the volume modulus of the third tow 180. The first composite ply 136 can be separated from the second composite ply 138. In other words, the first composite ply 136 and the second composite ply 138 can be formed as completely separate composite plies that do not share fibers or tows.

[0065] Reference Figure 2 , the composite airfoil 104 can include any number of one or more regions, where each region includes respective composite plies, and some or all of these composite plies can have different configurations (e.g., number of tows, material, volume modulus, etc.) from other composite plies in other regions. The composite airfoil 104 can include any number of one or more composite plies, and some or all of these composite plies can have different configurations (e.g., number of tows, material, volume modulus, etc.) from other composite plies in other regions.

[0066] During operation, the composite airfoil 104 rotates about the axis of rotation 106. Along the composite airfoil 104, forces can be experienced that are caused by at least one of an air flow passing over the composite airfoil 104, the rotation of the composite airfoil 104, an external force, or a combination thereof. The forces experienced along the composite airfoil 104 can be greater or in different directions between regions of the composite airfoil 104. As a non-limiting example, the dovetail portion 112 may experience a relatively large circumferential force due to the rotation of the rotatable disk 102 and the contact between the rotatable disk 102 and the composite airfoil 104, while the leading edge 114 of the composite airfoil 104 may experience a relatively large axial force due to the oncoming working air flow flowing from the leading edge 114 to the trailing edge 116.

[0067] Additionally reference Figure 3 and Figure 4, it is conceivable that the variation between the first composite ply 136, the second composite ply 138, and any other composite plies of the composite airfoil 104 can be provided based on the expected forces that will be experienced at a given region of the composite airfoil 104. As a non-limiting example, a composite ply including tows arranged together can be provided at the leading edge 114, while a lamellar tow (all fibers extending in a single direction) or a composite ply including two or more interwoven tows can be provided along the trailing edge 116.

[0068] Adjust the bulk modulus between the fibers of the corresponding tows (e.g., the first fiber 198 and the second fiber 199) to better accommodate the expected forces that will be experienced along the composite airfoil 104. As a non-limiting example, if it is expected that a single ply experiences a first force at a first location and a second force different from the first force at a second location, the bulk modulus of the tow or the fibers within the tow can be changed to accommodate the first force and the second force. As a non-limiting example, the ply includes only a first group of fibers 160, a first fiber having a first bulk modulus, and a second fiber having a second bulk modulus different from the first bulk modulus. The first fiber can better accommodate the first force, while the second fiber can better accommodate the second force. Thus, the first fiber can be placed at the location of the expected first force along the tow, and the second fiber can be placed at the location of the expected second force along the tow.

[0069] During the manufacture of the composite airfoil 104, the composite plies (e.g., the first composite ply 136, the second composite ply 138, etc.) can be formed and then placed by any suitable method. As a non-limiting example, each individual tow can be formed by manual or automatic placement and then the individual fibers are bonded together. As a non-limiting example, fiber tows can be automatically or manually interwoven with other fiber tows. As a non-limiting example, the composite plies can be placed along the corresponding portions of the composite airfoil 104 automatically or manually. Manual placement or shaping can be accomplished by manual manufacturing methods, while automatic placement or shaping can be accomplished by an automated fiber placement (AFP) manufacturing method. As used herein, the AFP manufacturing method refers to any suitable method of automatically physically placing fibers without direct human intervention. As a non-limiting example, the AFP manufacturing method can include placing plies along the composite airfoil 104 by a robot. As used herein, the manual manufacturing method refers to any suitable method of manually placing plies along the composite airfoil 104 with direct human intervention. As a non-limiting example, during a manual manufacturing process, a human can pick up and place plies along the composite airfoil 104.

[0070] Figure 5 is suitable for use in Figure 1Schematic side view of an exemplary component 200 used within a turbine engine 10. Component 200 is similar to component 100; thus, like parts will be identified with like numbers incremented to the 200 series, and it should be understood that the description of component 100 applies to component 200 unless otherwise noted.

[0071] Component 200 includes a composite airfoil 204. The composite airfoil 204 includes an airfoil portion 210. The airfoil portion 210 includes an outer wall 272 extending between a leading edge 214, a trailing edge 216, a root 218, and a tip 220. The airfoil portion 210 includes an interior 274. It is contemplated that the composite airfoil 204 can be a blade, vane, airfoil, or other component of any turbine engine (such as but not limited to a gas turbine engine, a turboprop engine, a turboshaft engine, a ducted turbofan engine, an unducted turbofan engine, or an open rotor turbine engine). The outer wall 272 can be a composite wall made of one or more layers of composite material. One or more layers of material can be applied during the same or different stages of manufacture of the composite airfoil 204.

[0072] The composite airfoil 204 is similar to the composite airfoil 104 in that the composite airfoil 204 includes a first region 256 and a second region 258 having composite plies (e.g., Figure 3 a first composite ply 136 and a second composite ply 138) having different configurations, respectively. However, the composite airfoil 204 does not include a dovetail portion (e.g., Figure 2 the dovetail portion 112). Instead, component 200 includes a spar 276 extending outwardly from the root 218 of the airfoil portion 210. Component 200 also includes a trunnion 278. The first region 256 can be disposed along the entire spar 276 or otherwise defined by the entire spar 276. The second region 258 can be disposed along a portion of the composite airfoil 204.

[0073] The spar 276 can extend into the interior 274. The spar 276 can be operatively coupled to the trunnion 278. The trunnion 278 can include any suitable material, such as but not limited to a metallic material or a composite material. It should be understood that the term composite material can also include a metal having a composite architecture (e.g., a metal matrix composite). In the case of a composite material, the trunnion 278 can be any suitable composite material, such as a 2D or 3D composite, a laminated skin, a woven or braided composite, or any other suitable composite material.

[0074] It should be understood that the spar 276 can include two or more regions that include corresponding composite plies. As a non-limiting example, the spar 276 can include two or more of the first region 256, the second region 258, or any other region.

[0075] During operation of the compound airfoil 204, the trunnion 278 can rotate about the pitch axis (Pax) in the rotational direction (Rd). When the spar 276 couples the trunnion 278 to the airfoil portion 210, rotation of the trunnion 278 in the rotational direction (Rd) causes the airfoil portion 210 to rotate about the pitch axis (Pax). This rotation can be used to control the pitch of the compound airfoil 204 such that the compound airfoil 204 is defined as a variable pitch airfoil assembly. Thus, the compound airfoil 204 can be defined as a variable pitch airfoil assembly. The pitch of the compound airfoil 204 can vary based on the operation or intended operation of a turbine engine (e.g., Figure 1 turbine engine 10) in which the compound airfoil 204 is disposed. The assembly 200 is applicable to turbine engines that include external fan blades, such as but not limited to non-ducted turbine engines.

[0076] When compared to conventional airfoils, benefits associated with the present disclosure include a compound airfoil having increased resilience to operating forces. As used herein, an operating force can be any force experienced along the compound airfoil during operation of the compound airfoil. An operating force can be, but is not limited to, a force caused by rotation of the compound airfoil, a force from a working air stream flowing against the compound airfoil, an external force applied to the compound airfoil, or a combination thereof. It is contemplated that different regions of the compound airfoil will experience different forces during operation of the compound airfoil. As a non-limiting example, the leading edge of the compound airfoil may experience the greatest axial force because the leading edge is the first region to contact the working air stream, while the dovetail portion may experience the greatest circumferential force during rotation of the compound airfoil due to contact with a corresponding portion of the turbine engine.

[0077] Conventional airfoils can include a homogeneous structure (e.g., formed from a single material having a single bulk modulus) or a structure including a composite material. In the case of conventional airfoils including a homogeneous structure, a material that is resilient to all operating forces is required. This, in turn, means that some regions of the conventional airfoil may be overly rigid in order to accommodate other regions of the conventional airfoil that will have a higher expected operating force. In the case of conventional airfoils using a composite material, in order to strengthen certain regions of the conventional airfoil, plies are laid such that their fibers have a specific orientation to accommodate the expected operating force in that region. Each individual ply of the conventional airfoil includes a tow of fibers having the same bulk modulus as each other. However, a composite airfoil as described herein utilizes at least a first tow and a second tow to customize the composite airfoil to ensure that each region of the airfoil can accommodate the expected operating force. A composite airfoil as described herein also includes plies having tows that can have different bulk moduli. The variation in bulk modulus within a single composite ply can be used to better customize how regions of the airfoil will accommodate the expected operating force. Additionally, it has been found that varying the bulk modulus between tows within a single composite ply helps to minimize flutter associated with the operation of the composite airfoil.

[0078] Within the scope not yet described, different features and structures of various embodiments can be used in combination as needed or interchanged with each other. The fact that a feature is not shown in all embodiments is not to be construed as meaning that it cannot be so shown, but rather is done so for the sake of brevity of description. Thus, the various features of different embodiments can be mixed and matched as needed 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 this disclosure.

[0079] This written description uses examples to describe aspects of the present disclosure described herein, including the best mode, and also enables any person skilled in the art to practice aspects of the present disclosure, including making and using any device or system and performing any combined method. The patentable scope of aspects of the present disclosure is defined by the claims and may include other examples that occur to those skilled in the art. If these other examples have structural elements that are indistinguishable from the literal language of the claims, or if they include equivalent structural elements that do not differ in substance from the literal language of the claims, then these other examples are intended to fall within the scope of the claims.

[0080] Further aspects are provided by the subject matter of the following clauses:

[0081] A composite airfoil, comprising: an airfoil portion having an outer wall extending between a root and a tip and between a leading edge and a trailing edge; a composite material made of one or more composite plies, the composite material being present at least in the airfoil portion of the composite airfoil; and a first composite ply of the one or more composite plies, the first composite ply comprising: a first group of fibers, wherein each fiber in the first group of fibers comprises a first centerline axis and a first volume modulus; and a second group of fibers, wherein each fiber in the second group of fibers comprises a second centerline axis and a second volume modulus different from the first volume modulus.

[0082] A composite airfoil assembly, comprising: an airfoil portion having an outer wall extending between a root and a tip and between a leading edge and a trailing edge; a spar extending at least partially within an interior of the airfoil portion and outwardly from the root; a composite material made of one or more composite plies, the composite material being present at least in the airfoil portion of the spar; and a first composite ply of the one or more composite plies, the first composite ply comprising: a first group of fibers, wherein each fiber in the first group of fibers comprises a first centerline axis and a first volume modulus; and a second group of fibers, wherein each fiber in the second group of fibers comprises a second centerline axis and a second volume modulus different from the first volume modulus.

[0083] The composite airfoil according to any of the preceding clauses, wherein the first group of fibers at least partially forms a first tow, and the second group of fibers at least partially forms a second tow, and the second centerline axis is not parallel to the first centerline axis.

[0084] The composite airfoil according to any of the preceding clauses, further comprising a third group of fibers, each fiber in the third group of fibers having a third centerline axis and a third volume modulus, the third volume modulus being different from the first volume modulus or the second volume modulus.

[0085] The composite airfoil according to any of the preceding clauses, wherein the first group of fibers at least partially forms a first tow, the second group of fibers at least partially forms a second tow, and the second centerline axis is not parallel to the first centerline axis, and the third group of fibers at least partially forms a third tow, and the third centerline axis is not parallel to the first centerline axis and the second centerline axis.

[0086] The composite airfoil according to any of the preceding clauses, wherein the first group of fibers and the second group of fibers are disposed within a single tow.

[0087] The composite airfoil according to any of the preceding clauses, wherein the first set of fibers and the second set of fibers are alternately spaced apart.

[0088] The composite airfoil according to any of the preceding clauses, wherein the second centerline axis forms a first angle with the first centerline axis, and the absolute value of the first angle is greater than or equal to 5 degrees and less than or equal to 60 degrees.

[0089] The composite airfoil according to any of the preceding clauses, wherein the first bulk modulus is greater than 1.05 times the second bulk modulus or less than 0.95 times the second bulk modulus.

[0090] The composite airfoil according to any of the preceding clauses, wherein the first composite ply is disposed within a first region of the composite airfoil, and the composite material further includes a second composite ply disposed within a second region of the composite airfoil, the second composite ply including a third set of fibers having a third bulk modulus.

[0091] The composite airfoil according to any of the preceding clauses, wherein the first composite ply is separated from the second composite ply.

[0092] The composite airfoil according to any of the preceding clauses, wherein the first region and the second region are each disposed along the outer wall.

[0093] The composite airfoil according to any of the preceding clauses, wherein the first region covers the second region.

[0094] The composite airfoil according to any of the preceding clauses, further including a dovetail portion extending from the root of the airfoil portion, the composite material being present in the dovetail portion, wherein the first region is disposed along the dovetail portion and the second region is disposed along the airfoil portion.

[0095] The composite airfoil according to any of the preceding clauses, wherein the second composite ply is a continuation of the first composite ply, and the first composite ply does not include the third set of fibers.

[0096] The composite airfoil according to any of the preceding clauses, wherein the third bulk modulus is not equal to the first bulk modulus and the second bulk modulus.

[0097] The composite airfoil according to any of the preceding clauses, further including a third set of fibers, the third set of fibers including a third centerline and a third bulk modulus.

[0098] The composite airfoil according to any of the preceding clauses, wherein the second centerline axis intersects the third centerline axis at a third included angle, and the absolute value of the third included angle is greater than or equal to 5 degrees and less than or equal to 60 degrees.

[0099] The composite airfoil assembly according to any of the preceding clauses, further comprising a trunnion, wherein the spar is partially disposed within the trunnion.

[0100] The composite airfoil assembly according to any of the preceding clauses, wherein the first set of fibers at least partially forms a first tow, and the second set of fibers at least partially forms a second tow, and the second centerline axis is not parallel to the first centerline axis.

[0101] The composite airfoil assembly according to any of the preceding clauses, further comprising a third set of fibers, each fiber in the third set of fibers having a third centerline axis and a third bulk modulus, and the third bulk modulus is not equal to the first bulk modulus or the second bulk modulus.

[0102] The composite airfoil assembly according to any of the preceding clauses, wherein the first set of fibers at least partially forms a first tow, the second set of fibers at least partially forms a second tow, and the second centerline axis is not parallel to the first centerline axis, and the third set of fibers at least partially forms a third tow, and the third centerline axis is not parallel to the first centerline axis and the second centerline axis.

[0103] The composite airfoil assembly according to any of the preceding clauses, wherein the first set of fibers and the second set of fibers are disposed within a single tow.

[0104] The composite airfoil assembly according to any of the preceding clauses, wherein the first set of fibers and the second set of fibers are alternately spaced apart.

[0105] The composite airfoil assembly according to any of the preceding clauses, wherein the second centerline axis forms a first included angle with the first centerline axis, and the absolute value of the first included angle is greater than or equal to 5 degrees and less than or equal to 60 degrees.

[0106] The composite airfoil assembly according to any of the preceding clauses, wherein the first bulk modulus is greater than 1.05 times the second bulk modulus or less than 0.95 times the second bulk modulus.

[0107] A composite airfoil component according to any of the preceding clauses, wherein the first composite ply is disposed within a first region of the composite airfoil component, and the composite airfoil component further includes a second composite ply disposed within a second region of the composite airfoil component, the second composite ply including a third set of fibers having a third bulk modulus.

[0108] A composite airfoil component according to any of the preceding clauses, wherein the first composite ply is separated from the second composite ply.

[0109] A composite airfoil component according to any of the preceding clauses, wherein the first region and the second region are each disposed along the outer wall.

[0110] A composite airfoil component according to any of the preceding clauses, wherein the first region covers the second region.

[0111] A composite airfoil component according to any of the preceding clauses, further including a dovetail portion extending from the root of the airfoil portion, the composite material being present in the dovetail portion, wherein the first region is disposed along the dovetail portion and the second region is disposed along the airfoil portion.

[0112] A composite airfoil component according to any of the preceding clauses, wherein the second composite ply is a continuation of the first composite ply, wherein the first composite ply does not include the third set of fibers.

[0113] A composite airfoil component according to any of the preceding clauses, wherein the third bulk modulus is not equal to the first bulk modulus and the second bulk modulus.

[0114] A turbine engine, comprising: a fan section, a compressor section, and a turbine section in a serial flow arrangement; and a composite airfoil according to any of the preceding clauses, the composite airfoil being disposed in the fan section, the compressor section, or the turbine section.

[0115] A turbine engine according to any of the preceding clauses, wherein the turbine engine is a ducted fan engine, and the fan section includes at least one external fan blade, wherein the composite airfoil is the at least one external fan blade.

[0116] A turbine engine according to any of the preceding clauses, further including a rotatable disk disposed within one of the compressor section or the turbine section, the rotatable disk having a slot, a portion of the composite airfoil being receivable within the slot.

[0117] A turbine engine according to any of the preceding clauses, wherein the first set of fibers at least partially forms a first tow, and the second set of fibers at least partially forms a second tow, and the second centerline axis is not parallel to the first centerline axis.

[0118] A turbine engine according to any of the preceding clauses, further comprising a third set of fibers, each fiber in the third set of fibers having a third centerline axis and a third bulk modulus, the third bulk modulus being different from the first bulk modulus or the second bulk modulus.

[0119] A turbine engine according to any of the preceding clauses, wherein the first set of fibers at least partially forms a first tow, the second set of fibers at least partially forms a second tow, and the second centerline axis is not parallel to the first centerline axis, and the third set of fibers at least partially forms a third tow, and the third centerline axis is not parallel to the first centerline axis and the second centerline axis.

[0120] A turbine engine according to any of the preceding clauses, wherein the first set of fibers and the second set of fibers are disposed within a single tow.

[0121] A turbine engine according to any of the preceding clauses, wherein the first set of fibers and the second set of fibers are alternately spaced apart.

[0122] A turbine engine according to any of the preceding clauses, wherein the second centerline axis forms a first angle with the first centerline axis, the first angle having an absolute value greater than or equal to 5 degrees and less than or equal to 60 degrees.

[0123] A turbine engine according to any of the preceding clauses, wherein the first bulk modulus is greater than 1.05 times the second bulk modulus or less than 0.95 times the second bulk modulus.

[0124] A turbine engine according to any of the preceding clauses, wherein the first composite ply is disposed within a first region of the turbine engine, and the turbine engine further comprises a second composite ply disposed within a second region of the turbine engine, the second composite ply comprising a third set of fibers having a third bulk modulus.

[0125] A turbine engine according to any of the preceding clauses, wherein the first composite ply is separated from the second composite ply.

[0126] A turbine engine according to any of the preceding clauses, wherein the first region and the second region are each disposed along the outer wall.

[0127] A turbomachine according to any of the preceding clauses, wherein the first region covers the second region.

[0128] A turbomachine according to any of the preceding clauses, further comprising a dovetail portion extending from the root of the airfoil portion, wherein the first region is disposed along the dovetail portion and the second region is disposed along the airfoil portion.

[0129] A turbomachine according to any of the preceding clauses, wherein the second composite ply is a continuation of the first composite ply, and the first composite ply does not include the third set of fibers.

[0130] A turbomachine according to any of the preceding clauses, wherein the third bulk modulus is not equal to the first bulk modulus and the second bulk modulus.

Claims

1. A composite airfoil, characterized in that: include: an airfoil portion having an outer wall extending between a root and a tip and between a leading edge and a trailing edge; a composite material made from one or more composite layups, the composite material being present at least in the airfoil portion of the composite airfoil; as well as A first composite layup of the one or more composite layups, the first composite layup comprising: a first set of fibers, wherein each fiber in the first set of fibers comprises a first centerline axis and a first bulk modulus; as well as A second group of fibers, wherein each fiber of the second group of fibers comprises a second centerline axis and a second bulk modulus different than the first bulk modulus.

2. The composite airfoil according to claim 1, characterized in that in: The first group of fibers at least partially forms a first tow; and The second group of fibers at least partially forms a second tow, and the second centerline axis is non-parallel to the first centerline axis.

3. The composite airfoil according to claim 1, wherein: Further included is a third group of fibers, each fiber in the third group of fibers having a third centerline axis and a third bulk modulus, the third bulk modulus not equal to the first bulk modulus or the second bulk modulus.

4. The composite airfoil according to claim 3, characterized in that in: The first group of fibers at least partially forms a first tow; The second group of fibers at least partially forms a second tow, and the second centerline axis is non-parallel to the first centerline axis; and The third group of fibers at least partially forms a third tow, and the third centerline axis is non-parallel to the first centerline axis and the second centerline axis.

5. The composite airfoil according to claim 1, wherein: in, The first group of fibers and the second group of fibers are disposed within a single tow.

6. The composite airfoil according to claim 5, characterized in that in, The first group of fibers and the second group of fibers are alternately spaced apart.

7. The composite airfoil according to claim 1, wherein: in, The second centerline axis forms a first angle with the first centerline axis, wherein the first angle has an absolute value greater than or equal to 5 degrees and less than or equal to 60 degrees.

8. The composite airfoil according to claim 1, wherein: in, The first bulk modulus is greater than 1.05 times or less than 0.95 times the second bulk modulus.

9. The composite airfoil according to any one of claims 1 to 8, characterized in that: in, The first composite layup is disposed within a first region of the composite airfoil, and the composite material further includes a second composite layup disposed within a second region of the composite airfoil, the second composite layup including a third set of fibers having a third bulk modulus.

10. The composite airfoil according to claim 9, characterized in that in, The first composite layup is separated from the second composite layup.

Images