Turbine engine having a composite airfoil including a non-metallic leading edge protection scroll

Abstract

A composite airfoil having a non-metallic leading edge protection wrap is provided. In one aspect, the airfoil has a composite core having a pressure sidewall and a suction sidewall, each extending between a core leading edge and a core trailing edge. A leading edge protection wrap protects the core leading edge and includes a rear wrap and a front wrap. The rear wrap wraps around the core leading edge and is connected to the composite core. The front wrap wraps around the core leading edge and is connected to the rear wrap. The rear wrap and the front wrap have leading edges spaced apart from each other. A filler is positioned between the leading edges of the rear wrap and the front wrap. A protection head is connected to the leading edge of the front wrap. Components of the leading edge protection wrap are made of a non-metallic material.

Description

[0001] Federally funded research

[0002] This invention was made with support from the United States Government. The Government may have certain rights in this invention. Technical Field

[0003] The present subject matter relates generally to turbine engines and, more particularly, to turbine engines having composite airfoils. Background Art

[0004] Some gas turbine engines include composite airfoils. For example, an aircraft gas turbine engine may include composite fan blades and composite airfoils in its compressor section and / or turbine section. Some composite airfoils used in gas turbine engines may require leading edge protection, for example, to protect against erosion, foreign object debris (FOD), and / or bird strike threats. The inventors of the present disclosure have developed various composite airfoils equipped with leading edge protection devices and methods of forming such composite airfoils. Summary of the Invention

[0005] Aspects and advantages of the invention will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the invention.

[0006] In one aspect, an airfoil for a turbine engine is provided. The airfoil includes a composite core having a pressure sidewall and a suction sidewall extending between a core leading edge and a core trailing edge. Further, the airfoil includes a leading edge protection scroll. The leading edge protection scroll includes a rear scroll wrapped around the core leading edge and connected to the pressure sidewall and suction sidewall of the composite core, the rear scroll having a leading edge and having a pressure sidewall and a suction sidewall. Further, the leading edge protection scroll includes a front scroll wrapped around the core leading edge and the leading edge of the rear scroll and connected to the pressure sidewall and suction sidewall of the rear scroll, the front scroll having a leading edge spaced apart from the leading edge of the rear scroll. The leading edge protection scroll further includes a filler positioned between the leading edge of the rear scroll and the leading edge of the front scroll.

[0007] On the other hand, an airfoil for a turbine engine is provided. The airfoil includes a composite core having a pressure sidewall and a suction sidewall extending between a core leading edge and a core trailing edge. In addition, the airfoil includes a leading edge protection scroll. The leading edge protection scroll includes a rear scroll, which wraps around the core leading edge and is connected to the pressure sidewall and the suction sidewall of the composite core, the rear scroll having a pressure sidewall and a suction sidewall. In addition, the leading edge protection scroll includes a head laminate, which is docked with the leading edge of the rear scroll. In addition, the leading edge protection scroll includes a front scroll, which has a pressure sidewall and a suction sidewall, the pressure sidewall of the front scroll is at least partially connected to the pressure sidewall of the rear scroll and at least partially connected to the head laminate, and the suction sidewall of the front scroll is at least partially connected to the suction sidewall of the rear scroll and at least partially connected to the head laminate.

[0008] In another exemplary aspect, an airfoil for a turbine engine is provided. The airfoil includes a composite core having a pressure sidewall and a suction sidewall extending between a core leading edge and a core trailing edge. Furthermore, the airfoil includes a leading edge protection wrap wrapped around the core leading edge and connected to the pressure sidewall and the suction sidewall of the composite core, the leading edge protection wrap being formed from a 3D woven material.

[0009] In another aspect, a method for forming an airfoil is provided. The method includes laying a composite core having a first sidewall and a second sidewall connected at a core leading edge. The method further includes wrapping a trailing wrap around the core leading edge of the composite core, the trailing wrap having the first sidewall and the second sidewall connected at a leading edge. The method further includes wrapping a leading wrap around the core leading edge of the composite core and the leading edge of the trailing wrap.

[0010] In another aspect, a method for forming an airfoil is provided. The method includes laying a composite core having a first sidewall and a second sidewall connected at a leading edge of the core. The method further includes wrapping a rear scroll around the leading edge of the core of the composite core, the rear scroll having a first sidewall and a second sidewall connected at a leading edge. The method further includes laying the first sidewall of the front scroll along the first sidewall of the rear scroll. The method also includes laying a head laminate at least partially on the first sidewall of the front scroll, the head laminate forming a butt joint with the leading edge of the rear shroud. In addition, the method includes laying the second sidewall of the front scroll at least partially on the head laminate and at least partially on the second sidewall of the rear scroll. The method also includes machining the leading edge radius of the airfoil.

[0011] In another aspect, a method of forming an airfoil is provided. The method includes laying up a composite core having a first sidewall and a second sidewall connected at a core leading edge. The method also includes wrapping a 3D braided leading edge scroll around the core leading edge.

[0012] These and other features, aspects and advantages of the present invention will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate various aspects of the invention and together with the description serve to explain the principles of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] A full and enabling disclosure of the invention, including the best mode thereof, to one of ordinary skill in the art is set forth in the specification, which refers to the accompanying drawings, in which:

[0014] Figure 1 is a schematic cross-sectional view of an exemplary aircraft gas turbine engine according to various embodiments of the present subject matter;

[0015] Figure 2 A perspective view of a fan blade according to an example embodiment of the present subject matter is provided;

[0016] Figure 3 Provided Figure 2 a cross-sectional view of an airfoil of a fan blade;

[0017] Figure 4 and Figure 5 Provided Figure 2 A close-up cross-sectional view of an airfoil of a fan blade;

[0018] Figure 6 Provided Figure 2 A close-up perspective cross-sectional view of an airfoil of fan blade 100;

[0019] Figure 7 A cross-sectional view of an airfoil with a leading scroll prior to machining is provided;

[0020] Figure 8 Provided Figure 7 A close-up cross-sectional view of the front scroll of the airfoil;

[0021] Figure 9 Provides the scroll before processing to specifications Figure 7 A close-up cross-sectional view of an airfoil;

[0022] Figure 10 A cross-sectional view of an airfoil having a leading scroll before machining is provided; and

[0023] Figure 11 Provided after processing according to specifications Figure 10 A close-up cross-sectional view of the front scroll of the airfoil. DETAILED DESCRIPTION

[0024] Reference will now be made in detail to present embodiments of the invention, one or more examples of which are illustrated in the accompanying drawings. The detailed description uses numerical and letter designations to refer to features in the drawings. Like or similar reference numerals in the drawings and the specification are used to refer to like or similar parts of the invention. As used herein, the terms "first," "second," and "third" are used interchangeably to distinguish one component from another and are not intended to indicate the position or importance of an individual component. The terms "upstream" and "downstream" refer to relative directions relative to the flow of a fluid in a fluid path. For example, "upstream" refers to the direction from which a fluid is flowing and "downstream" refers to the direction toward which a fluid is flowing.

[0025] Aspects of the present disclosure relate to a composite airfoil having a non-metallic leading edge protection scroll. Typically, metal scrolls have been used on composite airfoils for leading edge protection. The inventors of the present disclosure have recognized that metal-wound airfoils present certain challenges. For example, such metal-wound airfoils can become detached from their composite core during operation of the turbine in which the airfoil is located. As a result, the composite core of the airfoil may be exposed to the elements and may damage other components downstream of the airfoil, among other disadvantages. Therefore, to address these challenges, the inventors have invented various composite airfoils equipped with non-metallic leading edge protection scrolls and methods of forming such airfoils. Composite airfoils equipped with non-leading edge protection scrolls can be incorporated into any suitable turbine, such as an aircraft gas turbine engine.

[0026] In one aspect, an airfoil for a turbine engine is provided. In some embodiments, the airfoil is at least partially positioned within the core air flow path of a core engine of a gas turbine engine. For example, the airfoil may be positioned in the compressor section or the core turbine section of the core engine. In other embodiments, the airfoil may be positioned in other suitable locations. For example, the airfoil may be a fan blade positioned upstream of the fan section of the core engine.

[0027] The airfoil has a composite core. The composite core can be formed from any suitable composite material, such as a ceramic matrix composite (CMC) material or a polymer matrix composite (PMC) material. The composite core has a pressure sidewall and a suction sidewall, each of which extends between the core leading edge and the core trailing edge and is connected at the core leading edge and the core trailing edge. In this way, the composite core defines the shape of the airfoil. The airfoil further includes a non-metallic leading edge protection scroll. The leading edge protection scroll has two scrolls, including a rear scroll and a front scroll. The rear scroll wraps around the core leading edge of the composite core. In this regard, the rear scroll is positioned adjacent to the composite core. Specifically, the rear scroll has a pressure sidewall and a suction sidewall. The pressure sidewall of the rear scroll is connected to the pressure sidewall of the composite core, and the suction sidewall of the rear scroll is connected to the suction sidewall of the composite core. The rear scroll has a leading edge that is generally aligned with the core leading edge of the composite core.

[0028] The front scroll wraps around the core leading edge of the composite core and the leading edge of the rear scroll. The front scroll is connected to the pressure sidewall and suction sidewall of the rear scroll. The front scroll has a leading edge that is spaced apart from the leading edge of the rear scroll. The leading edge of the front scroll is in front of the leading edge of the rear scroll or upstream of the leading edge of the rear scroll. The front scroll is thinner than or not thicker than the rear scroll. The relatively thin front scroll can be used to form a sharp leading edge radius of the airfoil, while the relatively thick rear scroll is better able to provide structural integrity at the leading edge. The filler is positioned between the leading edge of the rear scroll and the leading edge of the front scroll. The leading edge protection scroll may also include a protective head connected to the leading edge of the front scroll. For example, the protective head can protect the leading edge of the airfoil from erosion. In addition, the airfoil can be coated with a protective coating to protect the airfoil from erosion, etc.

[0029] Various components of the leading edge protection scroll can be formed by non-metallic materials. For example, one or both of the rear scroll and the front scroll can be formed by non-metallic materials. The non-metallic material can be a fiber composite material. By way of example, the fiber composite material can be formed by at least one of S-glass, carbon, thermoplastic fiber, E-glass and Kevlar material. In some embodiments, at least one of the front scroll and the rear scroll is formed by a fiber material having fibers that are continuously wound around the leading edge of the core. This can improve the durability of the airfoil. By utilizing a non-metallic leading edge protection scroll, the risk of downstream damage to other engine components is reduced, particularly for airfoils located upstream of subsequent downstream rotor stages.

[0030] In another aspect, an airfoil for a turbine engine is provided. The airfoil includes a composite core having a pressure sidewall and a suction sidewall, each extending between a core leading edge and a core trailing edge. The airfoil includes a leading edge protection scroll. The leading edge protection scroll is formed from one or more non-metallic materials. The leading edge protection scroll includes a trailing scroll surrounding the core leading edge. The trailing scroll is connected to the pressure sidewall and the suction sidewall of the composite core. In particular, the trailing scroll has a pressure sidewall and a suction sidewall. The pressure sidewall of the trailing scroll is connected to the pressure sidewall of the composite core or is otherwise positioned adjacent to the pressure sidewall of the composite core, and the suction sidewall of the trailing scroll is connected to the suction sidewall of the composite core or is otherwise positioned adjacent to the suction sidewall of the composite core. The leading edge of the trailing scroll is substantially aligned with the core leading edge of the composite core.

[0031] The leading edge protection scroll further includes a head laminate formed by one or more layers. The head laminate is docked with the leading edge of the rear scroll. The leading edge protection scroll further includes a front scroll having a pressure sidewall and a suction sidewall. The pressure sidewall of the front scroll is at least partially connected to the pressure sidewall of the rear scroll and at least partially connected to the head laminate. The suction sidewall of the front scroll is at least partially connected to the suction sidewall of the rear scroll and at least partially connected to the head laminate. In some embodiments, excess blanks of the head laminate and the front scroll can be processed so that the leading edge of the airfoil can be processed according to specifications. In such an embodiment, the resulting leading edge radius can be formed partially by the head laminate and partially by the front scroll. When forming the resulting leading edge radius of the airfoil, the pressure sidewall and the suction sidewall of the front scroll can be discontinuous.

[0032] The leading edge protection wrap may also include a protection head connected to the resulting leading edge of the airfoil.In addition, the airfoil may be coated with a protective coating to protect the airfoil from erosion, etc.

[0033] In yet another aspect, an airfoil for a turbine engine is provided. The airfoil includes a composite core having a pressure sidewall and a suction sidewall, each extending between a core leading edge and a core trailing edge. The airfoil includes a leading edge protection wrap that wraps around the core leading edge and is connected to the pressure sidewall and the suction sidewall of the composite core.

[0034] The leading edge protection scroll may be formed of a non-metallic material. Notably, the leading edge protection scroll is formed of a 3D woven material.

[0035] Referring now to the accompanying drawings, Figure 1 A schematic cross-sectional view of a turbomachine implemented as a gas turbine engine for an aircraft is provided. Figure 1 In an embodiment of the present invention, the aircraft gas turbine engine is a high-bypass turbofan jet engine 10, referred to herein as a "turbofan 10." The turbofan 10 defines an axial direction A (extending parallel to a longitudinal centerline 12) and a radial direction R perpendicular to the axial direction A. The turbofan 10 also defines a circumferential direction C extending three hundred and sixty degrees (360°) about the longitudinal centerline 12.

[0036] The turbofan 10 includes a fan section 14 and a core engine 16 disposed downstream of the fan section 14. The core engine 16 includes a generally tubular engine cowling 18 defining an annular core inlet 20. Figure 1As shown schematically, the engine housing 18 surrounds, in series flow relationship, a compressor section, including a boost or low-pressure (LP) compressor 22, followed downstream by a high-pressure (HP) compressor 24; a combustion section 26; a turbine section, including an HP turbine 28, followed downstream by an LP turbine 30; and an exhaust nozzle section 32. The compressor section, combustion section 26, turbine section, and nozzle section 32 together define a core air flow path. An HP shaft or spool 34 drivingly connects the HP turbine 28 to the HP compressor 24, causing them to rotate concentrically together about the longitudinal centerline 12. An LP shaft or spool 36 drivingly connects the LP turbine 30 to the LP compressor 22, causing them to rotate concentrically together about the longitudinal centerline 12. Thus, each of the LP shaft 36 and the HP shaft 34 is a rotating component that rotates about an axial direction A during operation of the turbofan 10. The turbofan 10 may include multiple bearings to support such rotating components.

[0037] The fan section 14 includes a fan 38 having a plurality of fan blades 40 coupled to a disk 42 in a spaced-apart manner. The fan blades 40 extend outward from the disk 42 in a radial direction R. The fan blades 40 and the disk 42 rotate together about the longitudinal axis 12. The disk 42 is covered by a rotatable rotor 48 having an aerodynamic profile to facilitate airflow through the plurality of fan blades 40. In addition, the fan section 14 includes an annular fan casing or outer nacelle 50 that circumferentially surrounds the fan 38 and / or at least a portion of the core engine 16. The nacelle 50 is supported relative to the core engine 16 by a plurality of circumferentially spaced outlet guide vanes 52. Optionally, the nacelle 50 can also be supported by struts of the structural fan frame. In addition, a downstream section 54 of the nacelle 50 extends above the exterior of the core engine 16 to define a bypass airflow passage 56 therebetween.

[0038] During operation of turbofan 10, a volume of air 58 enters turbofan 10 through nacelle 50 and / or associated inlet 60 of fan section 14. As volume of air 58 passes through fan blades 40, a first portion of air 58, indicated by arrow 62, is directed or channeled into bypass airflow passage 56, and a second portion of air 58, indicated by arrow 64, is directed or channeled into an upstream section of the core air flow path, or more specifically, into annular core inlet 20 of LP compressor 22. The pressure of the second portion of air 64 is then increased as it is channeled through high pressure (HP) compressor 24. High pressure air 64 is then discharged into combustion section 26, where air 64 is mixed with fuel and combusted to provide combustion gases 66.

[0039] The combustion gases 66 are directed into and expanded through the HP turbine 28, wherein a portion of the thermal and / or kinetic energy from the combustion gases 66 is extracted via successive stages of HP turbine stator blades 68 coupled to the engine shroud 18 and HP turbine rotor blades 70 coupled to the HP shaft or spool 34, thereby rotating the HP shaft or spool 34 to support operation of the HP compressor 24. The combustion gases 66 then flow downstream into and expand through the LP turbine 30, wherein a second portion of the thermal and kinetic energy is extracted from the combustion gases 66 via successive stages of LP turbine stator blades 72 coupled to the engine shroud 18 and LP turbine rotor blades 74 connected to the LP shaft or spool 36 to rotate the LP shaft or spool 36 to support operation of the LP compressor 22 and rotation of the fan 38.

[0040] The combustion gases 66 are generally directed through the jet exhaust nozzle section 32 of the core engine 16 to provide propulsive force. Simultaneously, as the first portion of air 62 is directed through the bypass airflow passage 56 before being discharged from the fan nozzle exhaust portion 76 of the turbofan 10, the pressure of the first portion of air 62 is significantly increased, which also provides propulsive thrust. The HP turbine 28, the LP turbine 30, and the jet exhaust nozzle section 32 at least partially define a hot gas path 78 for directing the combustion gases 66 through the core engine 16.

[0041] It should be understood that Figure 1 The exemplary turbofan 10 depicted is by way of example, and in other exemplary embodiments, the turbofan 10 can have any other suitable configuration. For example, in other exemplary embodiments, the fan 38 can be configured in any other suitable manner (e.g., as a variable pitch fan) and further can be supported using any other suitable fan frame configuration. In addition, it should be understood that in other exemplary embodiments, any other suitable HP compressor 24 and HP turbine 28 configurations can be used. It should also be understood that in other exemplary embodiments, aspects of the present disclosure can be incorporated into any other suitable type of gas turbine engine. For example, aspects of the present disclosure can be incorporated into, for example, turboshaft engines, turboprop engines, turbojet engines, industrial and marine gas turbine engines, auxiliary power units, etc.

[0042] Furthermore, in some embodiments, the turbofan 10 includes one or more airfoils formed from composite materials, such as CMC or PMC materials. Composite airfoils for aircraft gas turbine engines formed from CMC materials are typically located in the hot section of the core engine 16, such as in the turbine section. For example, the airfoils of the HP turbine nozzle or the HP turbine stator vanes 68 may be formed from CMC materials. Further, the airfoils of the HP turbine rotor blades 70 may be formed from CMC materials. The airfoils in the LP turbine 30 may also be formed from CMC materials. Composite airfoils for aircraft gas turbine engines formed from PMC materials are typically located upstream of the hot section of the core engine 16, such as in the compressor section and the fan section 14. For example, the airfoils of the LP and HP compressor nozzles and the compressor blades of the LP compressor 22 and the HP compressor 24 may be formed from PMC materials. Further, the fan blades 40 of the fan 38 may be formed from PMC materials. According to inventive aspects of the present disclosure, a composite airfoil having a leading edge protection scroll is disclosed herein for providing leading edge protection against erosion, foreign object debris (FOD), bird strike threats, etc. The leading edge protection scroll can be used with or applied to any suitable composite airfoil for a turbine engine, such as any of the airfoils described above.

[0043] Now refer to Figure 2 、 3 , 4, 5 and 6, provide various views of an engine component having a composite airfoil equipped with a leading edge protection scroll. In particular, Figure 2 A perspective view of an engine component having a composite airfoil equipped with a leading edge protection scroll 150 is provided. Figure 2 In FIG. 1 , the engine component is a fan blade 100 of an aircraft gas turbine engine. Figure 3 Provides cross-section Figure 2 A close-up cross-sectional view of airfoil 120 of fan blade 100 is shown. Figure 4 and 5 Provided Figure 2 A close-up cross-sectional view of airfoil 120 of fan blade 100 is shown. Figure 6 Provided Figure 2 1 is a close-up perspective cross-sectional view of an airfoil 120 of a fan blade 100. Although in this exemplary embodiment, the leading edge protection scroll 150 is disclosed as an airfoil applied to a fan blade of an aircraft gas turbine engine, it should be understood that the leading edge protection scroll 150 may be applied to composite airfoils of other suitable gas turbine engines or turbine machines.

[0044] like Figure 2As depicted in FIG, fan blade 100 includes a root 110 and an airfoil 120. Root 110 includes a platform 112 and a dovetail 114. Dovetail 114 connects fan blade 100 to a fan disk, such as in FIG. Figure 1 The fan disk 42 is shown. Generally speaking, the airfoil 120 extends longitudinally outward from the root 110, such as in the radial direction R.

[0045] The airfoil 120 has a composite core 130. The composite core 130 has a core leading edge 136 (at Figure 2 Blocked by the leading edge protection scroll 150; see Figure 5 ) and the core trailing edge 138 extending between the pressure side wall 132 and the suction side wall 134. Figure 3 As best shown, the pressure side wall 132 has a concave shape, while the suction side wall 134 has a convex shape. The pressure side wall 132 and the suction side wall 134 are joined together at the core leading edge 136 and the core trailing edge 138 to define an airfoil shape. During operation, the fan blade 100 rotates in one direction so that the pressure side wall 132 follows the suction side wall 134. Thus, as Figure 2 As shown, fan blade 100 rotates into the page. In addition, composite core 130 of airfoil 120 extends between base 140 and tip 142, for example, along radial direction R. Span length SL is defined as Figure 2 Shown between the base 140 and the tip 142. The base 140 of the airfoil 120 is connected to the root 110.

[0046] In some embodiments, the composite core 130 is formed of a composite material. For example, for this embodiment, the composite core 130 is formed of a PMC material. In other embodiments, the composite core 130 may be formed of a CMC material. Exemplary matrix materials for CMC composite cores may include silicon carbide, silicon, silicon dioxide, aluminum oxide, or combinations thereof. Ceramic fibers may be embedded in the matrix, such as oxidation-stable reinforcing fibers, including monofilaments such as sapphire and silicon carbide (e.g., Textron's SCS-6), and rovings and yarns including silicon carbide (e.g., Nippon Carbon's ), Ube Industries and Dow Corning's ), aluminum silicates (such as Nextel's 440 and 480) and chopped whiskers and fibers (such as Nextel's 440 and ), and 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). This CMC material can have a thermal conductivity of approximately 1.3×10-6 in. / in. / °F to approximately 3.5 x 10 -6 The coefficient of thermal expansion may be in the range of inches per inch per degree F. In other embodiments, the composite core 130 may be formed from other suitable composite materials.

[0047] Notably, the airfoil 120 includes a leading edge protection wrap 150. The leading edge protection wrap 150 protects the composite core 130, particularly at the core leading edge 136 thereof. For example, the leading edge protection wrap 150 can protect the core leading edge 136 from erosion, FOD, and bird strike threats, among others. For this embodiment, the leading edge protection wrap 150 includes a trailing edge 160 that wraps around the core leading edge 136 of the composite core 130. Generally speaking, the trailing edge 160 enhances the structural integrity of the airfoil 120 and is particularly useful in preventing or minimizing structural damage to the airfoil 120, for example, due to bird strikes. Figure 4 As best shown in FIG, aft scroll 160 is connected to the pressure side wall 132 and the suction side wall 134 of the composite core 130. More specifically, aft scroll 160 has a pressure side wall 164 and a suction side wall 166. Aft scroll 160 also has a leading edge 162. The pressure side wall 164 of aft scroll 160 is connected to or otherwise positioned adjacent to the pressure side wall 132 of the composite core 130, and the suction side wall 166 of aft scroll 160 is connected to or otherwise positioned adjacent to the suction side wall 134 of the composite core body 130. Aft scroll 160 extends between a pressure side end 168 and a suction side end 170. In this regard, one end of aft scroll 160 terminates at the pressure side end 168 and the other end terminates at the suction side end 170.

[0048] The leading edge protection wrap 150 further includes a leading wrap 180 that wraps around the core leading edge 136 of the composite core 130 and the leading edge 162 of the trailing wrap 160. That is, the leading wrap 180 wraps around the leading edge 162 of the trailing wrap 160, which in turn wraps around the core leading edge 136 of the composite core 130. Therefore, the leading wrap 180 is an outer wrap relative to the trailing wrap 160.

[0049] The front scroll 180 has a leading edge 182 that is spaced apart from the leading edge 162 of the rear scroll 160. The leading edge 182 of the front scroll 180 is directed to, positioned at, or located upstream of the leading edge 162 of the rear scroll 160; thus, a front and rear representation of the front scroll 160 and the rear scroll 180 is obtained. As shown, the front scroll 180 is connected to the pressure sidewall 164 and the suction sidewall 166 of the rear scroll 160. More specifically, the front scroll 180 has a pressure sidewall 184 and a suction sidewall 186. The pressure sidewall 184 of the front scroll 180 is connected to the pressure sidewall 164 of the rear scroll 160 or is otherwise positioned adjacent to the pressure sidewall 164 of the rear scroll 160, and the suction sidewall 186 of the front scroll 180 is connected to the suction sidewall 166 of the rear scroll 160 or is otherwise positioned adjacent to the suction sidewall 166 of the rear scroll 160. The front scroll 180 extends between a pressure-side end 188 and a suction-side end 190 . In this regard, one end of the front scroll 180 terminates at the pressure-side end 188 and the other end thereof terminates at the suction-side end 190 .

[0050] In addition, the leading edge protection wrap 150 further includes a filler 200. The filler 200 is generally positioned between the leading edge 162 of the rear wrap 160 and the leading edge 182 of the front wrap 180. The filler 200 fills the cavity formed between the rear wrap 160 and the front wrap 180 in the front portion of the airfoil 120. The cavity formed between the rear wrap 160 and the front wrap 180 can extend between the base 140 and the tip 142 of the airfoil. The filler 200 can fill the entire cavity and, therefore, can extend from the base 140 to the tip 142 or extend the span length SL of the composite core 130 between the rear wrap 160 and the front wrap 180. In some embodiments, for example, the rear wrap 160, the front wrap 180, and the filler 200 extend the span length SL of the composite core 130. In this way, the entire span of the core leading edge 136 of the composite core 130 can be protected by the leading edge protection wrap 150. In other embodiments, the leading edge protection wrap 150 need not protect the entire span of the core leading edge 136 of the composite core 130 .

[0051] Filler 200 may be formed from a non-metallic material, such as at least one of a resin, an adhesive, a composite tow or fiber bundle, a 2D woven or knitted material, a 3D woven or knitted material, a rolled fiber, a single-toed material, and a preform (e.g., a preformed insert). In some embodiments, filler 200 is formed from the same resin used to form composite core 130. Thus, filler 200 can be co-molded with composite core 130 and does not require subsequent bonding. In embodiments where filler 200 and composite core 130 are co-molded, a sharp leading edge radius can be net molded.

[0052] In some embodiments, optionally, as Figure 6The illustrated leading edge protection wrap 150 may also include a protection head 210. The protection head 210 is connected to the leading edge 182 of the leading wrap 180. Thus, the protection head 210 is positioned upstream or forward of the leading wrap 180. Thus, the protection head 210 forms the leading edge of the airfoil 120. Advantageously, the protection head 210 can prevent or reduce erosion at the leading edge of the airfoil 120.

[0053] The protective head 210 can extend from the base 140 to the tip 142 or extend the span length SL of the composite core 130. Therefore, in some embodiments, the rear scroll 160, the front scroll 180, the filler 200, and the protective head 210 each extend the span length SL of the composite core 130. Further, the protective head 210 can be formed from any suitable non-metallic material. For example, the protective head 210 can be formed from any non-metallic material mentioned herein and can be a 2D or 3D braid. Therefore, in some embodiments, the rear scroll 160, the front scroll 180, the filler 200, and the protective head 210 can all be formed from non-metallic materials.

[0054] Further, in some embodiments, the airfoil 120 of the fan blade 100 may be coated with a protective coating 220, such as an environmental barrier coating. Figure 3 As shown, the entire perimeter of the airfoil 120 may be coated with a protective coating 220. In particular, as Figure 2 As shown, a protective coating 220 may be applied to the outer surface of the leading wrap 180 of the leading edge protective wrap 150, along the pressure side 132 and the suction side 134 of the composite core 130, and around the trailing edge 138 of the composite core 138. The protective coating 220 may be applied along the entire perimeter of the airfoil 120 and along the entire span of the airfoil 120. The protective coating 220 may be applied to the outer surface of the protective head 210, or the protective head 210 may be added to the airfoil 120 after the protective coating 220 has been applied.

[0055] The components of the leading edge protection scroll 150 can be formed from various non-metallic materials. In some embodiments, the rear scroll 160 and the front scroll 180 are formed from non-metallic materials. For example, the non-metallic material forming the rear scroll 160 and the front scroll 180 can be a fiber composite material. For example, in some embodiments, the fiber composite material is formed from at least one of S-glass, carbon, E-glass, and Kevlar.

[0056] In some embodiments, at least one of the rear scroll 160 and the front scroll 180 is formed from a fiber material having fibers that are continuously wrapped around the core leading edge 136. The fibers of a given scroll are "uninterrupted" around the core leading edge 136, such that they extend continuously from the pressure sidewall, around the leading edge, and to the suction sidewall of the given scroll. In some embodiments, at least one of the front scroll 180 and the rear scroll 160 is formed from a 3D braid having fibers that are continuously wrapped around the core leading edge 136 of the composite core 130. In other embodiments, at least one of the front scroll 180 and the rear scroll 160 is formed from a 2D braid having fibers that are continuously wrapped around the core leading edge 136 of the composite core 130.

[0057] As an example, Figure 6 As shown, the rear scroll 160 is formed of a non-metallic fiber material having fibers 172 (only four fibers are shown in section 6A of the rear scroll 160) that are continuously wrapped around the core leading edge 136 of the composite core 130. The fibers 172 can form part of a 3D or 2D braid. For example, the fibers 172 extend along at least a portion of the pressure side wall 164, wrap around the leading edge 162 (and therefore around the core leading edge 136), and continue to extend along the suction side wall 166 of the rear scroll 160. In some embodiments, one or more fibers 172 can extend continuously or uninterruptedly from the pressure side end 168 to the suction side end 170 of the rear scroll 160. The uninterrupted fibers 172 of the rear scroll 160 provide strength to the airfoil 120.

[0058] As another example, Figure 6 As shown, the leading scroll 180 is formed from a non-metallic fiber material having fibers 192 (only five fibers are shown in section 6B of the trailing scroll 180) that are continuously wrapped around the core leading edge 136 of the composite core 130 and the leading edge 162 of the trailing scroll 160. The fibers 192 may form part of a 3D or 2D braid. For example, the fibers 192 extend along at least a portion of the pressure side wall 184, wrap around the leading edge 182 (and therefore around the core leading edge 136 and leading edge 162), and continue along the suction side wall 166 of the leading scroll 180. In some embodiments, one or more fibers 192 may extend continuously or uninterruptedly from the pressure side end 168 to the suction side end 190 of the leading scroll 180. The uninterrupted fibers 192 of the leading scroll 180 provide strength to the airfoil 120. In some embodiments, the fibers 192 of the leading scroll 180 and the fibers 172 of the trailing scroll 160 may extend uninterrupted around the core leading edge 136 of the composite core 130 .

[0059] like Figure 6As shown, for this embodiment, the front scroll 180 is thinner than the rear scroll 160. The rear scroll 160 has a first thickness T1, and the front scroll 180 has a second thickness T2 that is thinner than the first thickness T1 of the rear scroll 160. In other words, the rear scroll 160 is thicker than the front scroll 180. The thickness of the rear scroll 160 can provide structural integrity to the composite core 130, especially at the core leading edge 136. The thinner front scroll 180 can be easily wound to form a small or sharp leading edge radius of the airfoil 120. Therefore, the two-scroll structure of the leading edge protection scroll 150 can enhance the structural integrity of the airfoil 120 while still meeting the sharp leading edge design intent of the airfoil 120. In some embodiments, the second thickness T2 of the front scroll 180 is less than half of the first thickness T1 of the rear scroll 160. In some other embodiments, the second thickness T2 of the front scroll 180 is less than one-third of the first thickness T1 of the rear scroll 160. As an example, the leading wrap 180 may be 0-0.003 mils thick and the trailing wrap may be 0-0.009 mils thick.

[0060] Furthermore, the rear scroll 160 may have different thicknesses. For example, as described above, the rear scroll 160 extends between a pressure side end 168 and a suction side end 170. The pressure side end 168 may be connected to the pressure side wall 132 of the composite core 130, and the suction side end 170 may be connected to the suction side wall 134 of the composite core 130. In some embodiments, the rear scroll 160 may be thicker at its leading edge 162 than at one or both of its pressure side end 168 and suction side end 170. In other embodiments, the rear scroll 160 may be thinner at its leading edge 162 than at one or both of its pressure side end 168 and suction side end 170.

[0061] The leading scroll 180 may also have different thicknesses. As described above, the leading scroll 180 extends between a pressure-side end 188 and a suction-side end 190. The pressure-side end 188 may be connected to the pressure-side wall 164 of the trailing scroll 160, and the suction-side end 190 may be connected to the suction-side wall 166 of the trailing scroll 160. In some embodiments, the leading scroll 180 may be thicker at its leading edge 182 than at one or both of its pressure-side end 188 and suction-side end 190. In other embodiments, the leading scroll 180 may be thinner at its leading edge 182 than at one or both of its pressure-side end 188 and suction-side end 190.

[0062] Furthermore, in some embodiments, Figure 3As best shown, composite core 130 defines a pressure side camber distance D1 (represented by the dashed line outlining the curvature of pressure sidewall 132) and a suction side camber distance D2 (represented by the dashed line outlining the curvature of suction sidewall 134). Pressure side camber distance D1 extends along pressure sidewall 132 of composite core 130 between a core leading edge 136 and a core trailing edge 138. Suction side camber distance D2 extends along suction sidewall 134 of composite core 130 between a core leading edge 136 and a core trailing edge 138.

[0063] In some embodiments, the aft scroll 160 is wrapped around the core leading edge 136 of the composite core 130 such that the aft scroll 160 extends at least ten percent (10%) of the pressure side camber distance D1 from the core leading edge 136 and at least ten percent (10%) of the suction side camber distance D2 from the core leading edge 136. In other embodiments, the aft scroll 160 is wrapped around the core leading edge 136 of the composite core 130 such that the aft scroll 160 extends at least twenty percent (20%) of the pressure side camber distance D1 from the core leading edge 136 and twenty percent (20%) of the suction side camber distance D2 from the core leading edge 136. In some other embodiments, the aft scroll 160 is wrapped around the core leading edge 136 of the composite core 130 such that the aft scroll 160 extends at least fifty percent (50%) of the pressure side camber distance D1 from the core leading edge 136 and fifty percent (50%) of the suction side camber distance D2 from the core leading edge 136. In other embodiments, the aft scroll 160 wraps around the core leading edge 136 of the composite core 130 such that the aft scroll 160 extends the entire pressure side camber distance D1 from the core leading edge 136 and the entire suction side camber distance D2 from the core leading edge 136 .

[0064] Furthermore, in some embodiments, the leading scroll 180 is wrapped around the core leading edge 136 of the composite core 130 such that the leading scroll 180 extends at least ten percent (10%) of the pressure side camber distance D1 from the core leading edge 136 and at least ten percent (10%) of the suction side camber distance D2 from the core leading edge 136. In some other embodiments, the leading scroll 180 is wrapped around the core leading edge 136 of the composite core 130 such that the leading scroll 180 extends at least twenty percent (20%) of the pressure side camber distance D1 from the core leading edge 136 and twenty percent (20%) of the suction side camber distance D2 from the core leading edge 136. In other embodiments, the leading scroll 180 is wrapped around the core leading edge 136 of the composite core 130 such that the leading scroll 180 extends at least fifty percent (50%) of the pressure side camber distance D1 from the core leading edge 136 and fifty percent (50%) of the suction side camber distance D2 from the core leading edge 136. In other embodiments, the leading scroll 180 wraps around the core leading edge 136 of the composite core 130 such that the leading scroll 180 extends the entire pressure side camber distance D1 from the core leading edge 136 and the entire suction side camber distance D2 from the core leading edge 136 .

[0065] Furthermore, for this embodiment, the leading scroll 180 wraps around the core leading edge 136 of the composite core 130 such that the leading scroll 180 extends further toward the core trailing edge 138 along at least one of the pressure side camber distance D1 and the suction side camber distance D2 than the trailing scroll 160. Figure 3 and 4 As shown, the leading scroll 180 is wrapped around the core leading edge 136 of the composite core 130 such that the leading scroll 180 extends further toward the core trailing edge 138 along the pressure side curvature distance D1 than the trailing scroll 160, and such that the leading scroll 180 extends further toward the core trailing edge 138 along the suction side curvature distance D2 than the trailing scroll 160. In alternative embodiments, the trailing scroll 160 is wrapped around the core leading edge 136 of the composite core 130 such that the trailing scroll 160 extends further toward the core trailing edge 138 along at least one of the pressure side curvature distance D1 and the suction side curvature distance D2 than the leading scroll 180. In some further embodiments, the leading scroll 180 and the trailing scroll are wrapped around the core leading edge 136 of the composite core 130 such that the leading scroll 180 and the trailing scroll 160 terminate at the same point along the pressure side curvature distance D1. Additionally or alternatively, in some embodiments, the leading scroll 180 and the trailing scroll wrap around the core leading edge 136 of the composite core 130 such that the leading scroll 180 and the trailing scroll 160 terminate at the same point along the suction side curved surface distance D2.

[0066] Generally speaking Figures 2 to 6, the forward scroll 150 can be applied to the composite core 130 using a suitable method to form the airfoil 120. As an example, the composite core 130 can be laid up in a suitable manner according to specifications. The aft scroll 160 can then be wrapped around the core leading edge 136 of the composite core 130. More specifically, the pressure sidewall 164 of the aft scroll 160 can be connected to or positioned adjacent to the pressure sidewall 132 of the composite core 130, and the suction sidewall 166 of the aft scroll 160 can be connected to or positioned adjacent to the suction sidewall 134 of the composite core 130. In some embodiments, the aft scroll 160 is constructed of composite prepreg or dry fabric, and the composite core 130 can be constructed as an airfoil preform.

[0067] The rear scroll 160 may have a thickness that is at least 25% greater than the thickness of any layer of the composite core 130. In addition, the rear scroll 160 may be deployed to the full span length SL ( Figure 2 ) or may be deployed along a portion of the span length SL. The pressure side end 168 of the pressure side wall 164 may abut against the outer layer of the pressure side wall 132 of the composite core 130. Similarly, the suction side end 170 of the suction side wall 166 may abut against the outer layer of the suction side wall 134 of the composite core 130, for example, Figure 4 shown.

[0068] Since the rear scroll 160 is wrapped around the core leading edge 136 of the composite core 130, the front scroll 180 may also be wrapped around the core leading edge 136 of the composite core 130. For example, the pressure sidewall 184 of the front scroll 180 may be connected to or positioned adjacent to the pressure sidewall 164 of the rear scroll 160, and the suction sidewall 186 of the front scroll 180 may be connected to or positioned adjacent to the suction sidewall 164 of the rear scroll 160. The front scroll 180 is thinner than the rear scroll 160. Further, the front scroll 180 may be deployed to the entire span length SL ( Figure 2 ) or may be deployed along a portion of the span length SL. The pressure side end 188 of the pressure side wall 184 may form a lap-shear joint with the outer layer of the pressure side wall 132 forming the composite core 130. Similarly, the suction side end 190 of the suction side wall 186 may form a lap-shear joint with the outer layer of the suction side wall 134 forming the composite core 130, such as Figure 4 shown.

[0069] When the front scroll 180 is wrapped around the core leading edge 136, the leading edge 182 of the front scroll 180 is spaced apart from the leading edge 162 of the rear scroll 160. At this point, a gap or cavity is formed between the front scroll 180 and the rear scroll 160. Filler 200 can be inserted into the cavity between the front scroll 180 and the rear scroll 160. The filler 200 can completely fill the cavity. In some example embodiments, the front scroll 180 can be placed on a forming tool so that the front scroll 180 is formed to specifications. The filler 200 can then be positioned at the leading edge 182 of the front scroll 180. Next, with the rear scroll 160 wrapped around the composite core 130, the composite core 130 can be laid on the forming tool on top of the front scroll 180 and the filler 200. The filler 200 can take its desired shape to fill the cavity between the front scroll 180 and the rear scroll 160. The entire airfoil 120 can then be removed from the forming tool, and the lap joint between the leading scroll 180 and the composite core 130 can be further ensured. A protective head 210 can be applied to the leading edge 182 of the leading scroll 180 to further protect the leading edge of the airfoil 120. Additionally, the entire airfoil or a portion thereof can be coated with a protective coating 220.

[0070] In some embodiments, the leading vortex 180 may be constructed of a composite prepreg or dry fabric, and as described above, the rear vortex 160 may also be constructed of a composite prepreg. The rear vortex 160 and the leading vortex 180 may be wrapped around the core leading edge 136 of the composite core 130 as described above so that they are net molded according to specifications. Because the leading edge vortex 150 is net molded, it is generally not necessary to machine the leading edge radius to specifications. The leading edge of the airfoil 120 is defined by the thickness of the rear vortex 160 and the leading vortex 180 and the geometry of the cross-section of the airfoil 120. Advantageously, the non-metallic leading edge vortex 150 can provide protection for the leading edge of the airfoil 120, such as from FOD and bird strikes.

[0071] Now refer to Figure 7 、 8 and 9, provide various views showing the progression of how an engine component having a composite airfoil equipped with a leading edge protection scroll is formed to specification according to an exemplary embodiment of the present disclosure. In particular, Figure 7 A cross-section of an airfoil 120 is provided having a leading edge scroll 150. For this embodiment, the airfoil 120 is a portion of a fan blade of an aircraft gas turbine engine. Figure 8 Provided Figure 7 A close-up cross-sectional view of the leading edge scroll 150 of the airfoil 120 is shown. Figure 9 Provides the following after the scroll 150 is machined to specifications: Figure 71 is a close-up cross-sectional view of a leading scroll 150 of an airfoil 120. Although in this exemplary embodiment, the leading edge protection scroll 150 is disclosed as being applied to a composite core airfoil of a fan blade of an aircraft gas turbine engine, it should be understood that the leading edge protection scroll 150 may be applied to other suitable composite airfoils of a gas turbine engine or turbomachine.

[0072] The leading scroll 150 can be applied to the composite core 130 using a suitable method to form the airfoil 120. As an example, the composite core 130 can be laid up to specification in a suitable manner. The trailing scroll 160 can then be wrapped around the core leading edge 136 of the composite core 130. The pressure sidewall 184 or the suction sidewall 186 of the leading scroll 180 can then be laid up on a forming tool. The composite core 130 and the wrapped trailing scroll 160 can be laid up on either the pressure sidewall 184 or the suction sidewall 186, depending on which is being laid up on the forming tool.

[0073] Next, a head laminate 230 having one or more layers is at least partially laid on the pressure side wall 184 or the suction side wall 186, depending on which is laid on the forming tool. For this embodiment, the head laminate 230 has two layers, including a first layer 232 and a second layer 134. It is worth noting that the head laminate 230 forms a butt joint with the leading edge 162 of the rear scroll 160. Figure 8 As best shown, the first layer 232 and the second layer 134 each abut the rear scroll 160 at its leading edge 162. Figure 7 As best shown, the head laminate 232 extends outwardly from the rear scroll 160. In some embodiments, the head laminate 230 has at least two layers. In other embodiments, the head laminate 230 has at least three layers. In other embodiments, the head laminate 230 has at least four layers. Furthermore, in some embodiments, at least one layer 232, 234 of the head laminate 230 has the same thickness as the rear scroll 160. For example, Figure 8 As best shown, both the first layer 232 and the second layer 234 have the same thickness as the rear scroll 160 .

[0074] As the head laminate 230 is laid up on the pressure sidewall 184 or the suction sidewall 186, depending on which is being laid up on the forming tool, the sidewall of the leading scroll 180 that has not yet been laid up is at least partially laid up on the head laminate 230 and at least partially laid up on the trailing scroll 160. For example, assuming the suction sidewall 134 of the leading scroll 180 is initially laid up on the forming tool, the pressure sidewall 132 may be at least partially laid up on the first layer 232 of the head laminate 230 and at least partially laid up on the trailing scroll 160, as shown. Figure 8 Best shown.

[0075] The filler 200 may be added at any suitable stage, for example, just before and / or after laying down the head laminate 230. In some embodiments, the filler 200 is positioned between at least one of: i) the head laminate 230 and the pressure sidewall 184 of the front scroll 180; and ii) the head laminate 230 and the suction sidewall 186 of the front scroll 180. In some embodiments, as Figure 8 and 9 As best shown, the filler 200 is positioned between the head laminate 230 and the pressure side wall 184 of the front scroll 180 and between the head laminate 230 and the suction side wall 186 of the front scroll 180. In this way, the cavities or gaps between the head laminate 230, the front scroll 180, and the rear scroll 160 are filled. This can benefit mechanical performance.

[0076] As the composite core 130 and leading edge protection wrap 150 are laid, excess stock can be machined off and the leading edge radius of the airfoil 120 can be formed to specifications. Figure 8 As best shown, the leading edge protection wrap 150 may be machined to specification along machine line ML to form a leading edge radius.

[0077] Figure 9 Depicts the leading edge radius machined to specifications. Figure 9 As shown, for this embodiment, the resulting airfoil 120 has a composite core 130 having a pressure sidewall 132 and a suction sidewall 134, each extending between a core leading edge 136 and a core trailing edge 138. The airfoil 120 has a leading edge protection wrap 150. The leading edge protection wrap 150 has a trailing wrap 160 wrapped around the core leading edge. The trailing wrap 160 is connected to or otherwise positioned adjacent to the pressure sidewalls 132 and suction sidewalls 134 of the composite core 130. The trailing wrap 160 has a leading edge 162 and has a pressure sidewall 164 and a suction sidewall 166. The leading edge protection wrap 150 also has a head laminate 230. The head laminate 230 forms an abutment with the leading edge 162 of the trailing wrap 160.

[0078] In addition, the leading edge protection scroll 150 has a front scroll 180 having a pressure sidewall 182 and a suction sidewall 184. The pressure sidewall 182 of the front scroll 180 is at least partially connected to the pressure sidewall 164 of the rear scroll 160 and at least partially connected to the head laminate 230, or more specifically, to the first layer 232 of the head laminate 230. The suction sidewall 184 of the front scroll 180 is at least partially connected to the suction sidewall 166 of the rear scroll 160 and at least partially connected to the head laminate 230, or more specifically, to the second layer 234 of the head laminate 230. As shown, the leading edge radius is partially formed by the head laminate 230 and the front scroll 180. In this regard, in this embodiment, the pressure sidewall 182 and the suction sidewall 184 of the front scroll 180 are discontinuous.

[0079] Now refer to Figure 10 and 11 , provides various views showing the progression of how an engine component having a composite airfoil equipped with a non-metallic leading edge protection scroll is formed to specification according to an exemplary embodiment of the present disclosure. In particular, Figure 10 A cross-sectional view of an airfoil 120 having a leading scroll 150 prior to machining is provided. For this embodiment, the airfoil 120 is a portion of a fan blade of an aircraft gas turbine engine. Figure 11 Provided after being processed according to specifications Figure 10 1 is a close-up cross-sectional view of a leading scroll 150 of an airfoil 120. Although in this exemplary embodiment, the leading edge protection scroll 150 is disclosed as a composite core airfoil applied to a fan blade of an aircraft gas turbine engine, it should be understood that the leading edge protection scroll 150 may be applied to other suitable composite airfoils of a gas turbine engine or turbomachine.

[0080] For this embodiment, the leading edge scroll 150 is a single 3D woven scroll. That is, the 3D woven leading edge scroll 150 is formed of a non-metallic 3D woven material. For example, the 3D woven leading edge scroll 150 can be an engineered multi-axial woven or woven glass fiber structure. In some embodiments, the 3D woven scroll 150 can be composed of a composite multifilament yarn. The use of such a multifilament yarn allows resin transfer molding (RTM) or RTM resin to mechanically bond / lock the 3D woven scroll 150 in the appropriate position relative to the composite core 130. In this regard, the 3D woven scroll 150 does not need to rely on or rely on chemical bonding like traditional metal leading edge structures. In some embodiments, the 3D woven leading edge scroll 150 can be co-molded with the composite core 130. In some embodiments, the 3D woven leading edge scroll 150 may include glass fibers woven in a 3D pattern. In other embodiments, the 3D woven leading edge scroll 150 may include silicon fibers woven in a 3D pattern.

[0081] As shown, the 3D braided leading edge wrap 150 has a pressure side wall 254 and a suction side wall 256. The 3D braided leading edge protection wrap 150 wraps around the core leading edge 136 and connects to the pressure side wall 132 and the suction side wall 134 of the composite core 130. The pressure side wall 254 of the 3D braided leading edge wrap 150 terminates at a pressure side end 258, and the suction side wall 256 terminates at a suction side end 260. Notably, the pressure side wall 254 tapers from a pressure taper point 262 to the pressure side end 258, and the suction side wall 256 tapers from a suction taper point 264 to the suction side end 266. The tapering of the pressure side wall 254 and the suction side wall 256 creates a smooth transition between the layers of the composite core 130 and the 3D braided leading edge protection wrap 150. In addition, for this embodiment, the suction side wall 256 of the 3D braided leading edge protection scroll 150 extends along its suction side curved surface, while the pressure side wall 254 extends along its pressure side curved surface, as shown in FIG. Figure 10 and 11 The 3D braided leading edge protection scroll 150 can be deployed to the entire span length SL ( Figure 2 ) or can be deployed along a portion of the wingspan length SL.

[0082] The 3D braided leading edge wrap 150 can be applied to the composite core 130 to form the airfoil 120 in the following exemplary manner. The 3D braided leading edge wrap 150 can be wrapped around the core leading edge 136 of the composite core 130. In particular, the pressure side wall 254 of the 3D braided leading edge wrap 150 is connected to or otherwise positioned adjacent to the pressure side wall 132 of the composite core 130, and the suction side wall 256 of the 3D braided leading edge wrap 150 is connected to or otherwise positioned adjacent to the suction side wall 134 of the composite core 130. The 3D braided leading edge wrap 150 is tightly wrapped around the core leading edge 136 of the core body 130, thereby preventing voids or cavities from being created. It is noteworthy that the composite core 130 is laid up to allow for the 3D braided leading edge wrap 150 to be wrapped or applied thereto. In particular, the pressure sidewall 132 and the suction sidewall 134 of the composite core 130 may be laid up to account for the tapered geometry of the 3D woven leading edge wrap 150. The complementary layup of the composite core 130 facilitates placement or wrapping of the 3D woven leading edge wrap 150 onto the composite core 130.

[0083] like Figure 10 As best shown, the 3D braided leading edge wrap 150 initially has excess stock 270 extending generally outwardly from the junction of the pressure sidewall 254 and the suction sidewall 256. To more generally create the leading edge 252 ( Figure 11 ) and the radius of the leading edge, and use appropriate processing technology to machine away the excess blank 270. Figure 11As shown, the radii of the leading edge 252 and the airfoil 120 are machined to specification. Thereafter, optionally, a protective head (not shown) may be applied to the leading edge 252 to provide additional protection. Additionally, optionally, one or more protective coatings may be applied to the airfoil 120.

[0084] This written description uses examples to disclose aspects of the invention, including the best mode, and also to enable those skilled in the art to practice aspects of the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.

[0085] Further aspects of the invention are provided by the subject matter of the following clauses:

[0086] 1. An airfoil for a turbine engine, the airfoil comprising: a composite core having a pressure sidewall and a suction sidewall extending between a core leading edge and a core trailing edge; a leading edge protection scroll comprising: a rear scroll wrapped around the core leading edge and connected to the pressure sidewall and suction sidewall of the composite core, the rear scroll having a leading edge and having a pressure sidewall and a suction sidewall; a front scroll wrapped around the core leading edge and the leading edge of the rear scroll and connected to the pressure sidewall and suction sidewall of the rear scroll, the front scroll having a leading edge spaced apart from the leading edge of the rear scroll; and a filler positioned between the leading edge of the rear scroll and the leading edge of the front scroll.

[0087] 2. An airfoil according to any preceding clause, further comprising: a protective head connected to the leading edge of the leading scroll.

[0088] 3. An airfoil according to any preceding clause, wherein the aft wrap and the forward wrap are formed from a non-metallic material.

[0089] 4. An airfoil according to any preceding clause, wherein the non-metallic material is a fiber composite material.

[0090] 5. An airfoil according to any preceding clause, wherein the fiber composite material is formed from at least one of S-glass, carbon, E-glass and Kevlar.

[0091] 6. An airfoil according to any preceding clause, wherein the rear wrap has a first thickness and the front wrap has a second thickness that is less than the first thickness.

[0092] 7. An airfoil according to any preceding clause, wherein the second thickness of the leading wrap is less than half the first thickness of the trailing wrap.

[0093] 8. An airfoil according to any preceding clause, wherein the second thickness of the leading wrap is less than one third of the first thickness of the trailing wrap.

[0094] 9. An airfoil according to any preceding clause, wherein the composite core defines a pressure sidewall camber distance and a suction sidewall camber distance, the pressure sidewall camber distance extending along the pressure sidewall of the composite core between a core leading edge and a core trailing edge, and the suction sidewall camber distance extending along the composite core between a core leading edge and a core trailing edge; and wherein the trailing vortex wraps around the core leading edge of the composite core such that the trailing vortex extends at least 20% of the pressure sidewall camber distance from the core leading edge and at least 20% of the suction sidewall camber distance from the core leading edge.

[0095] 10. An airfoil according to any preceding clause, wherein at least one of the leading and trailing wraps has fibres wrapped uninterruptedly around the leading edge of the core.

[0096] 11. An airfoil according to any preceding clause, wherein the filler is formed from at least one of a resin, an adhesive, a composite tow, a 2D braid, a 3D braid, a rolled fiber, and a preform.

[0097] 12. An airfoil according to any preceding clause, wherein the composite core extends between a base and a tip defining a span length, and wherein the leading scroll, the trailing scroll and the filler extend over the span length of the composite core.

[0098] 13. An airfoil according to any preceding clause, wherein the leading scroll extends between a pressure side end and a suction side end, the pressure side end being connected to the pressure side wall of the trailing scroll, and the suction side end being connected to the suction side wall of the trailing scroll, and wherein the leading scroll is thinner at a leading edge of the leading scroll than at one or both of the pressure side end and the suction side end.

[0099] 14. An airfoil according to any preceding clause, wherein the trailing scroll extends between a pressure side end and a suction side end, the pressure side end being connected to the pressure side wall of the composite core, and the suction side end being connected to the suction side wall of the composite core, and wherein the trailing scroll is thinner at a leading edge of the trailing scroll than at one or both of the pressure side end and the suction side end.

[0100] 15. An airfoil for a turbine engine, the airfoil comprising: a composite core, the composite core having a pressure sidewall and a suction sidewall, the pressure sidewall and the suction sidewall each extending between a core leading edge and a core trailing edge; a leading edge protection vortex, comprising: a rear vortex, the rear vortex wrapped around the core leading edge and connected to the pressure sidewall and suction sidewall of the composite core, the rear vortex having a pressure sidewall and a suction sidewall; a head laminate, the head laminate forming a butt joint with the leading edge of the rear vortex; and a front vortex, the front vortex having a pressure sidewall and a suction sidewall, the pressure sidewall of the front vortex being at least partially connected to the pressure sidewall of the rear vortex and at least partially connected to the head laminate, the suction sidewall of the front vortex being at least partially connected to the suction sidewall of the rear vortex and at least partially connected to the head laminate.

[0101] 16. An airfoil according to any preceding clause, further comprising: a filler positioned between at least one of: the head laminate and the pressure sidewall of the leading scroll; and the head laminate and the suction sidewall of the leading scroll.

[0102] 17. An airfoil according to any preceding clause, wherein the head laminate has at least two layers, and wherein at least one of the at least two layers of the head laminate and the trailing edge wrap have the same thickness.

[0103] 18. An airfoil for a turbine engine, the airfoil comprising: a composite core having a pressure sidewall and a suction sidewall extending between a core leading edge and a core trailing edge; and a leading edge protection scroll wrapped around the core leading edge and connected to the pressure sidewall and the suction sidewall of the composite core, the leading edge protection scroll being formed of a 3D woven material.

[0104] 19. An airfoil according to any preceding clause, wherein the leading edge protection wrap has a leading edge, a pressure sidewall connected to the pressure sidewall of the composite core, and a suction sidewall connected to the suction sidewall of the composite core.

[0105] 20. An airfoil according to any preceding clause, wherein the pressure side wall of the leading edge protection wrap tapers gradually from a pressure taper point located along the pressure side wall of the leading edge protection to the pressure side end of the leading edge protection wrap, and the suction side wall of the leading edge protection wrap tapers gradually from a suction taper point located along the suction side wall of the leading edge protection to the suction side end of the leading edge protection wrap.

[0106] 21. A method of forming an airfoil, comprising: laying a composite core, the composite core having a first sidewall and a second sidewall connected at a core leading edge; wrapping a rear scroll around the core leading edge of the composite core, the rear scroll having a first sidewall and a second sidewall connected at a leading edge; and wrapping a front scroll around the core leading edge of the composite core and the leading edge of the rear scroll.

[0107] 22. A method according to any preceding clause, further comprising inserting a filler material between the leading edge of the rear wrap and the leading edge of the front wrap.

[0108] 23. The method according to any preceding clause, further comprising: connecting a protective head to the leading edge of the leading scroll.

[0109] 24. A method according to any preceding clause, wherein the rear scroll is formed from a non-metallic material.

[0110] 25. A method according to any preceding clause, wherein the leading scroll is formed from a non-metallic material.

[0111] 26. A method according to any preceding clause, wherein the rear scroll and the front scroll are formed from a non-metallic material.

[0112] 27. A method according to any preceding clause, wherein the non-metallic material forming the front scroll and / or the rear scroll is a fiber composite material.

[0113] 28. A method according to any preceding clause, wherein the fiber composite material is formed from at least one of S-glass, carbon, E-glass and Kevlar.

[0114] 29. A method according to any preceding clause, wherein the rear wrap has a first thickness and the front wrap has a second thickness that is thinner than the first thickness.

[0115] 30. A method according to any preceding clause, wherein the second thickness of the front wrap is less than half the first thickness of the rear wrap.

[0116] 31. A method according to any preceding clause, wherein the second thickness of the front wrap is less than one third of the first thickness of the rear wrap.

[0117] 32. A method according to any of the preceding clauses, wherein the composite core defines a pressure sidewall curvature distance and a suction sidewall curvature distance, the pressure sidewall curvature distance extending along the pressure sidewall of the composite core between a core leading edge and a core trailing edge, the suction sidewall curvature distance extending along the suction sidewall of the composite core between a core leading edge and a core trailing edge, and wherein the trailing vortex is wrapped around the core leading edge of the composite core such that the trailing vortex extends at least 20% of the pressure sidewall curvature distance from the core leading edge and at least 20% of the suction sidewall curvature distance from the core leading edge.

[0118] 33. A method according to any preceding clause, wherein at least one of the leading and trailing scrolls has fibres wrapped uninterruptedly around the leading edge of the core.

[0119] 34. A method according to any preceding clause, wherein at least one of the leading scroll and the trailing wrap is formed from a 3D braid having fibres wrapped uninterruptedly around the leading edge of the core.

[0120] 35. A method according to any preceding clause, wherein at least one of the leading scroll and the trailing wrap is formed from a 2D braid having fibres wrapped uninterruptedly around the leading edge of the core.

[0121] 36. A method according to any preceding clause, wherein the filler is formed from at least one of a resin, an adhesive, a composite tow, a 2D braid, a 3D braid, a rolled fiber, and a preform.

[0122] 37. A method according to any preceding clause, wherein the composite core extends between a base and a tip defining a span length, and wherein the leading scroll, the trailing scroll and the filler extend over the span length of the composite core.

[0123] 38. A method according to any preceding clause, wherein the leading vortex extends between a pressure side end and a suction side end, the pressure side end being connected to the pressure side wall of the trailing vortex, and the suction side end being connected to the suction side wall of the trailing vortex, and wherein the leading vortex is thinner at a leading edge of the leading vortex than at one or both of the pressure side end and the suction side end.

[0124] 39. A method according to any preceding clause, wherein the rear scroll extends between a pressure side end and a suction side end, the pressure side end being connected to the pressure side wall of the composite core, and the suction side end being connected to the suction side wall of the composite core, and wherein the rear scroll is thinner at a leading edge of the rear scroll than at one or both of the pressure side end and the suction side end.

[0125] 40. A method for forming an airfoil, comprising: laying a composite core having a core leading edge; wrapping a rear vortex around the core leading edge of the composite core, the rear vortex having a first side wall and a second side wall connected at the leading edge; laying the first side wall of the front vortex along the first side wall of the rear vortex; laying a head laminate at least partially on the first side wall of the front vortex, the head laminate forming a butt joint with the leading edge of the rear vortex; laying the second side wall of the front vortex at least partially on the head laminate and at least partially on the second side wall of the rear vortex; and machining the leading edge radius of the airfoil.

[0126] 41. The method of any preceding clause, further comprising: adding a filler between the first side wall of the front scroll and the head laminate.

[0127] 42. The method of any preceding clause, further comprising: adding a filler between the second side wall of the front scroll and the head laminate.

[0128] 43. A method according to any preceding clause, wherein the first sidewall of the rear wrap is thicker than the first sidewall of the front wrap.

[0129] 44. A method according to any preceding clause, wherein the second side wall of the rear scroll is thicker than the second side wall of the front scroll.

[0130] 45. A method according to any preceding clause, wherein the head laminate is formed from at least two layers.

[0131] 46. ​​The method of any preceding clause, wherein the leading edge radius is formed partially by the head laminate and partially by the leading wrap, wherein the first and second sidewalls of the leading wrap are discontinuous at the leading edge radius of the airfoil.

[0132] 47. A method according to any preceding clause, wherein the airfoil is a component of an aircraft gas turbine engine.

[0133] 48. A method according to any preceding clause, wherein the airfoil is a component of a compressor of an aircraft gas turbine engine.

[0134] 49. A method according to any preceding clause, wherein the airfoil is a component of a turbine of an aircraft gas turbine engine.

[0135] 50. A method according to any preceding clause, wherein the airfoil is a component of a fan of a turbofan.

[0136] 51. A method according to any preceding clause, wherein the first and second sidewalls of the trailing scroll are the suction and pressure sidewalls respectively.

[0137] 52. A method according to any preceding clause, wherein the first and second sidewalls of the leading scroll are suction and pressure sidewalls respectively.

[0138] 53. A method of forming an airfoil, comprising: laying up a composite core having a first sidewall and a second sidewall connected at a core leading edge; and wrapping a 3D braided leading edge scroll around the core leading edge.

[0139] 54. The method of any preceding clause, further comprising: machining a 3D woven leading edge wrap to form a leading edge radius of the airfoil.

[0140] 55. The method of any preceding clause, wherein the 3D woven leading edge scroll is formed from a non-metallic 3D woven material.

[0141] 56. A method according to any preceding clause, wherein a 3D woven leading edge wrap is wrapped around the core leading edge such that a first sidewall of the 3D woven leading edge wrap is positioned adjacent to a first sidewall of the composite core and a second sidewall of the 3D woven leading edge wrap is positioned adjacent to a second sidewall of the composite core.

[0142] 57. The method of any preceding clause, wherein the 3D braided leading edge wrap is wrapped around the core leading edge of the composite core such that no voids or cavities are created between the 3D braided leading edge wrap and the composite core.

[0143] 58. The method of any preceding clause, wherein a first sidewall of the 3D braided leading edge wrap tapers from a first tapered point to an end of the first sidewall. Additionally or alternatively, a second sidewall of the 3D braided leading edge wrap tapers from a second tapered point to an end of the second sidewall.

[0144] 59. A method according to any preceding clause, wherein the 3D braided leading edge scroll is co-moulded with the composite core.

[0145] 60. The method of any preceding clause, wherein the 3D braided leading edge scroll is an engineered multi-axial braided structure.

[0146] 61. A method according to any preceding clause, wherein the 3D woven leading edge scroll is a woven fiberglass structure.

[0147] 62. A method according to any preceding clause, wherein the 3D braided leading edge scroll is formed from composite multifilament yarns.

[0148] 63. A method according to any preceding clause, wherein the 3D braided leading edge scroll is formed from silicone fibres braided in a 3D pattern.

Claims

1. An airfoil for a turbine engine, characterized in that The airfoil comprises: a composite core having a pressure sidewall and a suction sidewall extending between a core leading edge and a core trailing edge, wherein the composite core comprises a ceramic matrix composite or a polymer matrix composite; and Leading edge protection scroll, including: a rear scroll wrapped around the core leading edge and connected to the pressure side wall and the suction side wall of the composite core, the rear scroll having a leading edge and having a pressure side wall and a suction side wall; a front scroll wrapped around the core leading edge and the leading edge of the rear scroll and connected to the pressure side wall and the suction side wall of the rear scroll, the front scroll having a leading edge spaced apart from the leading edge of the rear scroll, wherein one end of the front scroll terminates at a first termination point and the other end terminates at a second termination point, the first termination point being directly connected to the pressure side wall of the rear scroll and the second termination point being directly connected to the suction side wall of the rear scroll, the rear scroll and the front scroll defining a cavity between the leading edge of the rear scroll and the leading edge of the front scroll; and A filler is inserted into the cavity.

2. The airfoil according to claim 1, wherein: Further including: A protective head is connected to the leading edge of the front scroll.

3. The airfoil according to claim 1, wherein: The rear scroll and the front scroll are formed of non-metallic materials.

4. The airfoil according to claim 3, wherein: The non-metallic material is a fiber composite material.

5. The airfoil according to claim 4, wherein: The fiber composite material is formed of at least one of S-glass, carbon, E-glass, and Kevlar.

6. The airfoil according to claim 1, wherein: The rear wrap has a first thickness and the front wrap has a second thickness that is less than the first thickness.

7. The airfoil according to claim 6, wherein: The second thickness of the front wrap is less than half of the first thickness of the rear wrap.

8. The airfoil according to claim 6, wherein: The second thickness of the front scroll is less than one third of the first thickness of the rear scroll.

9. The airfoil according to claim 1, wherein: the composite core defining a pressure sidewall camber distance and a suction sidewall camber distance, the pressure sidewall camber distance extending along the pressure sidewall of the composite core between the core leading edge and the core trailing edge, and the suction sidewall camber distance extending along the suction sidewall of the composite core between the core leading edge and the core trailing edge; and The rear scroll wraps around the core leading edge of the composite core so that the rear scroll extends at least 20% of the pressure side wall curved surface distance from the core leading edge and at least 20% of the suction side wall curved surface distance from the core leading edge.

10. The airfoil according to claim 1, wherein: At least one of the leading scroll and the trailing scroll has fibers continuously wrapped around the leading edge of the core.

11. The airfoil according to claim 1, wherein: The filler is formed from at least one of a resin, a binder, a composite tow, a 2D braid, a 3D braid, a rolled fiber, and a preform.

12. The airfoil according to claim 1, wherein: The composite core extends between a base and a tip defining a span length, and wherein the leading scroll, the trailing scroll, and the filler extend across the span length of the composite core.

13. The airfoil according to claim 1, wherein: The leading scroll extends between a pressure side end and a suction side end, the pressure side end being connected to the pressure side wall of the trailing scroll, and the suction side end being connected to the suction side wall of the trailing scroll, and wherein the leading scroll is thinner at the leading edge of the leading scroll than at one or both of the pressure side end and the suction side end.

14. The airfoil according to claim 1, wherein: The rear scroll extends between a pressure side end connected to the pressure side wall of the composite core and a suction side end connected to the suction side wall of the composite core, and wherein the rear scroll is thinner at the leading edge of the rear scroll than at one or both of the pressure side end and the suction side end.

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