Composite case for a turbine engine

Abstract

A casing for a turbine engine includes a composite segment. The composite segment has (i) an arcuate shape or an annular shape and (ii) a circumferential direction. The composite segment includes a matrix and a plurality of circumferential reinforcement fiber tows embedded in the matrix. Each of the plurality of circumferential reinforcement fiber tows extends in the circumferential direction and has a plurality of undulations in the circumferential direction to allow the matrix material of the composite segment to expand circumferentially.

Description

Technical Field

[0001] This disclosure relates to composite housings and methods for manufacturing composite housings (particularly composite housings for aircraft engines). Background Technology

[0002] Turbine engines used in aircraft typically consist of a fan and a turbo-engine section arranged in flow communication with each other. A combustor is located in the turbo-engine to generate combustion gases that drive a turbine in the turbo-engine, and the turbine can be used to drive the fan. A portion of the air flowing into the fan flows through the turbo-engine as core air, while another portion flows around the core section as bypass air through the turbine. The turbo-engine section may include one or more compressors to compress the core air before it flows into the combustor. Composite materials can be used to manufacture various components of turbine engines, especially when the turbine engine is intended for use in aircraft. Attached Figure Description

[0003] Features and advantages of this disclosure will become apparent from the following description of various exemplary embodiments, as illustrated in the accompanying drawings, wherein similar reference numerals generally denote identical, functionally similar, and / or structurally similar elements.

[0004] Figure 1 This is a schematic cross-sectional view of a turbine engine used in aircraft.

[0005] Figure 2 This is a cross-sectional view of a part of a turbine engine, showing... Figure 1 Detail 2 in the text.

[0006] Figure 3A It is possible Figure 1 A schematic diagram of the fan housing used in the turbine engine.

[0007] Figure 3B It is possible Figure 1 A schematic diagram of another fan housing used in the turbine engine.

[0008] Figure 4 yes Figure 3A The image shows a cross-sectional view of the fan housing.

[0009] Figure 5 It is possible to manufacture Figure 1 A flowchart of the process for the composite section of the fan casing used in a turbine engine.

[0010] Figure 6A This is a schematic diagram of a 3D fiber weaving pattern used for three-dimensional (3D) woven fabrics.

[0011] Figure 6B It is along Figure 6A The line 6B-6B in the middle is cut off Figure 6A A schematic cross-sectional view of the fiber weave pattern shown.

[0012] Figure 6C It is similar to Figure 6A A schematic cross-sectional view of a fiber weave pattern shown, but with different interlocking fiber patterns.

[0013] Figure 6D It is similar to Figure 6A A schematic cross-sectional view of a fiber weave pattern shown, but with an alternative interlocking fiber pattern.

[0014] Figure 7 This is a schematic cross-sectional view of a portion of a 3D woven fabric that can be used to form composite sections.

[0015] Figure 8A It is a schematic cross-sectional view of the layers and stacks that can be used to form composite sections.

[0016] Figure 8B It is a schematic cross-sectional view of the layers and stacks that can be used to form composite sections.

[0017] Figure 8C It is a schematic cross-sectional view of the layers and stacks that can be used to form composite sections.

[0018] Figure 9 This is a top view of a two-dimensional (2D) woven fabric, which can be used to form composite segments and can be used in... Figures 8A to 8C Used in any of the stacking processes. Detailed Implementation

[0019] The features, advantages, and embodiments of this disclosure will be set forth or apparent from consideration of the following detailed description, accompanying drawings, and claims. Furthermore, the following detailed description is exemplary and intended to provide further explanation, without limiting the scope of the claimed disclosure.

[0020] Various embodiments are discussed in detail below. Although specific embodiments are discussed, this is for illustrative purposes only. Those skilled in the art will recognize that other components and constructions can be used without departing from this disclosure.

[0021] As used herein, the terms “first,” “second,” “third,” etc., are used interchangeably to distinguish one component from another and are not intended to indicate the location or importance of the components.

[0022] Unless otherwise stated herein, the terms “connection,” “fixation,” “attachment,” “linkage,” etc., refer to both direct connection, fixation, attachment, or linking, and indirect connection, fixation, attachment, or linking through one or more intermediate components or features.

[0023] As used herein, the terms "axial" and "axially" refer to a direction and orientation that extends substantially parallel to the centerline of the turbine engine or other component. Furthermore, the terms "radial" and "radially" refer to a direction and orientation that extends substantially perpendicular to the centerline. Additionally, as used herein, the terms "circumferential" and "circumferentially" refer to a direction and orientation that extends in an arc around the centerline.

[0024] Unless the context clearly indicates otherwise, the singular forms “a,” “a,” and “the” include plural references.

[0025] Scope limitations are combined and interchanged herein and throughout the specification and claims. Unless the context or language otherwise indicates, such scopes are identified and include all subscopes contained herein. For example, all scopes disclosed herein include endpoints, and endpoints may be combined independently of each other.

[0026] As used herein, the term "composite" refers to a material having two or more constituent materials. A composite material can be a combination of at least two or more metals, nonmetals, or metal and nonmetal elements or materials. Examples of composite materials can be, but are not limited to, polymer matrix composites (PMCs), ceramic matrix composites (CMCs), and metal matrix composites (MMCs). Composite materials can be formed from a matrix material and reinforcing elements, such as fibers (referred to herein as reinforcing fibers).

[0027] As used herein, "reinforcing fiber" can include, for example, glass fiber, carbon fiber, steel fiber, or para-aramid fiber, such as Kevlar®, available from DuPont of Wilmington, Delaware. Reinforcing fiber can be in the form of a fiber bundle comprising multiple fibers forming the bundle.

[0028] As used in this article, a “prefab” is a three-dimensional woven fabric formed by multiple reinforcing fibers, including warp and weft fiber bundles.

[0029] As used herein, a “composite component” refers to a structure or component comprising any suitable composite material. A composite component (e.g., a composite airfoil) may comprise several layers or plies of composite material. The stiffness, material, and dimensions of the layers or plies may vary to achieve a desired composite component or composite portion of a component having a predetermined weight, size, stiffness, and strength.

[0030] One or more layers of adhesive can be used to form or join composite components. The adhesive may require curing at elevated temperatures or other hardening techniques.

[0031] As used herein, PMC refers to a class of materials. PMC materials can be prepregs. A prepreg is a reinforcing material (e.g., reinforcing fibers) pre-impregnated with a polymer matrix material. Non-limiting examples of processes for producing polymer prepregs include: hot melt prepreg, in which molten resin is deposited onto the fiber reinforcing material; and powder prepreg, in which resin is deposited onto the fiber reinforcing material, as a non-limiting example, electrostatically deposited onto the fiber reinforcing material, and then adhered to the fibers, as a non-limiting example, in an oven or with the aid of heated rollers.

[0032] Resins used as matrix materials for PMCs are generally classified as thermosetting or thermoplastic resins. Thermoplastic resins are typically categorized as polymers that repeatedly soften and flow upon heating, and harden upon sufficient cooling due to physical rather than chemical changes. Well-known examples of thermoplastic resins include nylon, thermoplastic polyesters, polyaryletherketones (PAEs), 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). Conversely, thermosetting resins do not undergo significant softening upon heating once fully cured into a rigid solid, but rather thermally decompose upon sufficient heating. Well-known examples of thermosetting resins include epoxy resins, bismaleimide (BMI), and polyimide resins.

[0033] Instead of using prepregs with thermoplastic polymers, another non-limiting example utilizes woven fabrics. Woven fabrics may include, but are not limited to, dry carbon fibers woven together with thermoplastic polymer fibers or filaments. Non-prepreg woven structures can be fabricated in a similar manner. With this method, the fiber volume of the part can be customized by specifying the relative concentrations of the woven or braided thermoplastic fibers and reinforcing fibers. Furthermore, different types of reinforcing fibers can be woven or braided 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, can be incorporated into glass fibers to enhance impact characteristics—a design feature of parts located near the engine inlet—and thermoplastic fibers provide bonding for the reinforcing fibers.

[0034] In yet another non-limiting example, resin transfer molding (RTM) can be used to form at least a portion of a composite part. Typically, RTM involves applying dry fibers to a mold or cavity. The dry fibers can include prepreg, braided material, woven material, or any combination thereof. Resin can be pumped into or otherwise supplied to the mold or cavity to impregnate the dry fibers. The impregnated fibers combined with the resin are then cured and removed from the mold. The composite part may require post-curing treatment upon removal from the mold. RTM can be a vacuum-assisted process. That is, air in the cavity or mold can be removed and replaced with resin before heating or curing. The placement of the dry fibers can also be manual or automatic. The dry fibers can be shaped to form the composite part or guide the resin. Optionally, additional layers or reinforcing layers of materials different from the dry fibers can be included or added before heating or curing.

[0035] As used herein, the term "metal" refers to a metal-based material, including but not limited to titanium, iron, aluminum, stainless steel, and nickel alloys. A metallic material or metal alloy can be a combination of at least two or more elements or materials, at least one of which is a metal.

[0036] As used herein, an alloy is "based on" a particular element when that element constitutes the largest weight percentage (by total weight) of all the elements contained in the alloy. For example, an iron-based alloy has a higher weight percentage of iron than any other single element present in the alloy.

[0037] As mentioned above, certain components of gas turbine engines, particularly those used in aircraft, can be made of composite materials. For example, these components can include various housings and shell structures. For instance, a rotating airfoil assembly (such as a fan or compressor rotor) includes a rotating airfoil and can have a shell surrounding the airfoil. Including a composite material shell provides significant weight reduction for use in aircraft turbine engines. Composite materials include reinforcing fiber bundles, such as reinforcing fiber bundles formed from carbon fibers. Carbon fibers have a very low coefficient of thermal expansion (CTE), almost zero in many engineering applications; therefore, composite shells made of carbon fiber composites typically expand very little during engine operation. When the shell is used for rotating airfoils where the airfoil is also a composite material, both the airfoil and the shell expand similarly during changes in operating conditions. However, when the shell is used for rotating airfoils with metal blades, a larger radial clearance is maintained between the metal blades and the composite shell to prevent the blades from rubbing against the shell during engine operation, as the metal blades expand more than the shell. This larger radial clearance will reduce engine performance and fuel efficiency.

[0038] This paper discloses a shell (composite shell) that includes at least a composite section. However, even when the airfoil includes metal blades, this composite shell design allows for thermal expansion along with the airfoil. More specifically, the composite shell includes circumferential reinforcing fiber bundles embedded in a matrix. These circumferential reinforcing fiber bundles undulate in the circumferential direction (e.g., undulating circumferential layup) to allow the matrix material to expand circumferentially. Compared to composites without undulations, this structure increases the CTE of the composite because thermal expansion is now primarily controlled by the matrix material. For example, when the material is a resin, the CTE of the resin is much higher than that of carbon fiber, resulting in a more matched CTE between the rotor (such as a rotating airfoil assembly) and the shell, improving engine performance.

[0039] Figure 1 This is a schematic cross-sectional view of a turbine engine 100 that can be used on an aircraft. The turbine engine 100 has an axial direction A (extending parallel to the longitudinal centerline (axis) 101, where the longitudinal centerline (axis) 101 is located at... Figure 1 (Shown for reference) the radial direction R and the circumferential direction C. The circumferential direction C extends in the direction of rotation about the longitudinal centerline (axis) 101 (axial direction A). Figure 1 In the depicted embodiment, the turbine engine 100 is a non-ducted fan engine or an open fan engine. The turbine engine 100 has three different thrust-generating airflows during operation. Figure 1 The "three-flow engines" (labeled S1, S2, and S3) are described in further detail below. The turbocharger 100 includes a fan section 102 and a turbocharger 104 disposed downstream of the fan section 102.

[0040] Figure 1 The turbocharged engine 104 depicted includes a compressor section 110, a combustion section 120, and a turbine section 130 in a series flow relationship. The turbocharged engine 104 is substantially surrounded within a core shroud 106, which is substantially tubular and annularly surrounds the turbocharged engine 104. The core shroud 106 defines a core inlet 141, and in this embodiment, the core inlet 141 is annular. Figure 1As schematically shown, compressor section 110 includes a turbocharger or low-pressure (LP) compressor 112, followed downstream by a high-pressure (HP) compressor 114. Combustion section 120 is downstream of compressor section 110. Turbine section 130 is downstream of combustion section 120 and includes a high-pressure (HP) turbine 132, followed downstream by a low-pressure (LP) turbine 134. Turbocharged engine 104 also includes a core air exhaust nozzle 143 (also referred to as an injection exhaust nozzle) downstream of turbine section 130. Compressor section 110, combustion section 120, and turbine section 130 together at least partially define a core airflow path (also referred to as a core duct 140) extending from core inlet 141 to core air exhaust nozzle 143, through which core air A5 flows. As will be discussed in more detail below, turbocharged engine 104 includes a high-pressure (HP) shaft 108 or HP spool and a low-pressure (LP) shaft 109. HP shaft 108 drives HP turbine 132 to HP compressor 114. HP turbine 132 and HP compressor 114 rotate synchronously via HP shaft 108. LP shaft 109 drives LP turbine 134 to LP compressor 112. LP turbine 134 and LP compressor 112 rotate synchronously via LP shaft 109.

[0041] Each of the LP compressor 112 and HP compressor 114 may include multiple compressor stages. In each stage, multiple compressor blades 116 rotate relative to corresponding multiple static compressor impellers 118 (also referred to as nozzles) to compress or pressurize the core air A5 through that stage. In a single compressor stage, the multiple compressor blades 116 may be arranged in a ring extending radially outward from the blade platform relative to a longitudinal centerline (axis) 101 to the blade tip (e.g., extending in the radial direction R). The compressor blades 116 may be part of a compressor rotor including a disk, wherein the compressor blades 116 extend radially from the disk. Other configurations of the compressor rotor may be used, including, for example, impeller disks, wherein the disk and the compressor blades 116 are integrally formed as a single piece. The corresponding static compressor impellers 118 are positioned upstream of and adjacent to the rotating compressor blades 116. The static compressor impellers 118 for a stage of the compressor may be mounted circumferentially to the core housing 107. The core housing 107 may at least partially define the core airflow path (core duct 140). Each compressor stage can be used to sequentially compress core air A5 flowing through the core airflow path (core duct 140) to generate compressed air A6. Any suitable number of compressor blades 116, static compressor impellers 118, and compressor stages can be used.

[0042] Each of the HP turbine 132 and LP turbine 134 may further include multiple turbine stages. In each stage, multiple turbine blades 136 rotate relative to corresponding multiple static turbine blades 138 (also referred to as nozzles) to extract energy from the combustion gas A7 passing through the stage. The turbine blades 136 may be part of a turbine rotor. Any suitable configuration of the turbine rotor may be used, including, for example, a disk from which the multiple turbine blades 136 extend. The corresponding static turbine blades 138 are positioned upstream of and adjacent to the rotating turbine blades 136. The static turbine blades 138 of the first stage of the turbine may be mounted to the core housing 107 in a circumferential arrangement.

[0043] In combustion section 120, fuel received from the fuel system (not shown) is injected into combustion chamber 124 of combustor 122 via fuel nozzle 126. The fuel mixes with compressed air A6 from compressor section 110 to form a fuel-air mixture, which is then burned to produce combustion products (i.e., combustion gases A7). As will be discussed further below, adjusting the fuel metering unit (not shown) of the fuel system alters the amount of fuel supplied to combustion chamber 124, and thus changes the amount of propulsive thrust generated by turbine engine 100. Combustion gases A7 are discharged from combustion chamber 124. These combustion gases A7 can be directed to turbine blades 136 of HP turbine 132, and then to turbine blades 136 of LP turbine 134, driving (rotating) the turbine blades 136 of both HP turbine 132 and LP turbine 134. Any suitable number of turbine blades 136, static turbine blades 138, and turbine stages can be used. After flowing through the turbine section 130, the combustion gas A7 is discharged from the turbine engine 100 through the core air exhaust nozzle 143 to provide propulsive thrust.

[0044] The turbocharged engine 100, and more specifically, the turbocharged engine 104, also includes one or more drive shafts. As described above, the turbocharged engine 104 includes an HP shaft 108 drivingly connecting an HP turbine 132 to an HP compressor 114, and an LP shaft 109 drivingly connecting an LP turbine 134 to an LP compressor 112. More specifically, the turbine rotor of the HP turbine 132 is connected to the HP shaft 108, and the compressor rotor of the HP compressor 114 is connected to the HP shaft 108. Combustion gas A7 is directed into and expands through the HP turbine 132, wherein a portion of the thermal or kinetic energy from the combustion gas A7 is extracted via one or more stages of the turbine blades 136 and static turbine blades 138 of the HP turbine 132. This causes the HP shaft 108 to rotate, which supports the operation (self-sustaining cycle) of the HP compressor 114 and rotates the compressor rotor, thereby rotating the compressor blades 116 of the HP compressor 114. In this way, the combustion gas A7 performs work on the HP turbine 132. The combustion gas A7 is then directed into the LP turbine 134 and expands through it. Here, a second portion of thermal or kinetic energy is extracted from the combustion gas A7 via one or more stages of turbine blades 136 and static turbine blades 138 of the LP turbine 134. This causes the LP shaft 109 to rotate, which supports the operation (self-sustaining cycle) of the LP compressor 112 and causes the compressor rotor to rotate, thereby rotating the compressor blades 116 of the LP compressor 112. In this way, the combustion gas A7 does work on the LP turbine 134. The HP shaft 108 and the LP shaft 109 are coaxially arranged about a longitudinal centerline (axis) 101. The diameter of the HP shaft 108 is larger than the diameter of the LP shaft 109, and the HP shaft 108 is located radially outside the LP shaft 109. The HP shaft 108 and the LP shaft 109 are rotatable about the longitudinal centerline (axis) 101 and are coupled to rotatable elements, such as the compressor rotor and the turbine rotor, as discussed above.

[0045] Figure 1 The fan section 102 shown includes a fan, referred to herein as primary fan 150. In the depicted embodiment, primary fan 150 is an open rotor fan, also known as a non-ducted fan. Primary fan 150 has a plurality of primary fan blades 151 coupled to fan disk 153. Figure 1 As depicted, the primary fan blades 151 extend outward from the fan disk 153 in a generally radial direction R. Figure 1The image depicts a primary fan blade 151, but multiple primary fan blades 151 can be arranged at equal intervals around a longitudinal centerline (axis) 101. The primary fan blades 151 and the fan disk 153 can rotate together about the longitudinal centerline (axis) 101 via a fan shaft 155. The fan disk 153 is covered by a fan hub 157, which is aerodynamically shaped to facilitate airflow through the multiple primary fan blades 151. In this embodiment, the fan hub 157 can rotate together with the primary fan blades 151 and the fan disk 153.

[0046] like Figure 1 As shown, the fan shaft 155 is connected to the LP shaft 109 via a reduction gearbox or power gearbox (also referred to as gearbox assembly 159). Therefore, the LP shaft 109 is driven to the primary fan. The gearbox assembly 159 is... Figure 1 The diagram is schematically shown. Gearbox assembly 159 includes multiple gears for adjusting the rotational speed of fan shaft 155, thereby adjusting the rotational speed of primary fan 150 relative to LP shaft 109. Gearbox assembly 159 can be used to reduce the rotational speed to a speed more efficient for primary fan 150. Gearbox assembly 159 may have gear ratios of 4:1 to 12:1, or 7:1 to 12:1, or 4:1 to 10:1, or 5:1 to 9:1, or 6:1 to 9:1, and may be constructed in a planetary configuration or a rotary star configuration. For non-ducted fan engines (e.g., turbine engine 100), gearbox assembly 159 may have gear ratios of 4:1 to 10:1. Gearbox assembly 159 may be a single-stage gearbox or a compound gearbox (e.g., having multiple stages).

[0047] In the case of variable pitch fans, such as Figure 1 As depicted, for example, a plurality of primary fan blades 151 are rotatable relative to the fan disk 153 about a fan blade pitch axis PB. Each of the primary fan blades 151 can be connected to the fan disk 153 via a pitch bearing 162, which allows rotation of the primary fan blade 151 about the pitch axis PB. The primary fan blade 151 can be rotated within the pitch bearing 162 by a pitch actuator 164, which is operatively coupled to the primary fan blade 151 to change the pitch of the corresponding primary fan blade 151. One or more pitch actuators 164 can be used, and in some embodiments, the pitch actuators 162 cause the primary fan blades 151 to rotate uniformly. A fan actuation system 160 controls one or more pitch actuators 164 to change the pitch of the primary fan blades 151 about their respective pitch axes PB. The fan actuation system 160 can be disposed within the fan hub 157.

[0048] Fan section 102 includes multiple fan guide vanes 172 ( Figure 1(Only one is shown in the image). Fan guide vanes 172 are circumferentially spaced and arranged around a longitudinal centerline (axis) 101 as part of a fan guide vane array 170. Figure 1 In the depicted embodiment, the fan guide vane 172 is a static airfoil and cannot rotate about the longitudinal centerline (axis) 101. Each fan guide vane 172 is mounted to the fan shroud 174 and extends outward from the fan shroud 174 generally along the radial direction R. In the case of a variable pitch fan, as... Figure 1 As depicted, for example, multiple fan guide vanes 172 are rotatable relative to the fan shroud 174 about the fan guide vane pitch axis PV. A fan guide vane actuation system 166 can be used to change the pitch of the fan guide vanes 172. The fan guide vane actuation system 166 can operate similarly to the fan actuation system 160 discussed above, and that discussion applies here. Therefore, the same reference numerals are used for the pitch bearing 162 and the pitch actuator 164 of the fan guide vane actuation system 166.

[0049] A fan shroud 174 annularly surrounds at least a portion of the core shroud 106 and is positioned generally along the radial direction R outside the core shroud 106. The fan shroud 174 and the core shroud 106 together define the casing of the turbine engine 100. A downstream section of the fan shroud 174 extends above the front portion of the core shroud 106 to define a fan flow path, also referred to as a fan duct 181. Incoming air enters through the fan duct inlet 183, passes through the fan duct 181, and exits through the fan exhaust nozzle 185 to generate propulsive thrust. The fan duct 181 is an annular duct positioned generally along the radial direction R outside the core duct 140. The fan shroud 174 and the core shroud 106 are connected together and are supported by a plurality of struts 176 ( Figure 4 (Only one is shown in the image) Supports. Struts 176 are circumferentially spaced around a longitudinal centerline (axis) 101 and extend radially outward from the core shroud 106. Each of the plurality of struts 176 has an aerodynamic profile to guide the airflow therefrom.

[0050] The turbine engine 100 includes an inlet duct 187. The inlet duct 187 extends between an engine inlet 189, a core inlet 141, and a fan duct inlet 183. The engine inlet 189 is generally defined at the front end of a fan shroud 174 and positioned along the axial direction A between a primary fan 150 and a fan guide vane 172. The inlet duct 187 is an annular duct positioned along the radial direction R inside the fan shroud 174. Air flowing downstream along the inlet duct 187 is split (but not necessarily uniformly) by a splitter 178 of the core shroud 106 to the core duct 140 and the fan duct 181. The inlet duct 187 is wider than the core duct 140 in the radial direction R. The inlet duct 187 is also wider than the fan duct 181 in the radial direction R.

[0051] Fan section 102 also includes an intermediate fan 190. The intermediate fan 190 includes multiple intermediate fan blades 192 ( Figure 4 (Only one is shown). A plurality of intermediate fan blades 192 are rotatable about a longitudinal centerline axis 101. In the depicted embodiment, the intermediate fan 190 is drivenly coupled to the LP turbine 134 via an LP shaft 109. The plurality of intermediate fan blades 192 may be arranged at equal circumferential spacing about the longitudinal centerline axis 101. The intermediate fan blades 192 may be part of a rotor including a central hub (such as a disk 194), and each of the plurality of intermediate fan blades 192 extends radially from the disk 194. Other configurations of the compressor rotor may be used, including, for example, an impeller disk, wherein the disk 194 and the intermediate fan blades 192 are integrally formed as a single piece.

[0052] Multiple intermediate fan blades 192 are annularly surrounded by a fan shroud 174 (e.g., duct type). In this respect, an intermediate fan 190 is positioned inside the fan shroud 174 along the radial direction R. The intermediate fan 190 is positioned within an inlet duct 187 upstream of the core duct 140 and the fan duct 181. The ratio of the span of the primary fan blade 151 to the span of the intermediate fan blade 192 (span measured from the root to the tip of the respective blade) is greater than 2 and less than 10 to achieve the desired benefits of the third flow (S3), particularly the additional thrust provided by the third flow (S3) to the engine, which allows for the smaller diameter of the primary fan blade 152. Multiple inlet intermediate fan blades 196 are positioned upstream of and adjacent to the rotating intermediate fan blades 192. The inlet intermediate fan blades 196 may be mounted to the fan shroud 174 in a circumferential arrangement.

[0053] During operation of the turbine engine 100, the initial airflow, or incoming air A1, passes through the primary fan blades 151 of the primary fan 150 and splits into a first airflow (the first portion of air, referred to herein as primary bypass air A2) and a second airflow (the second portion of air, referred herein as engine air A3). The primary bypass air A2 bypasses the engine inlet 189 and flows radially R on the outside of the fan shroud 174, generally along the axial direction A. The primary bypass air A2 is accelerated by the primary fan blades 151 and passes through the fan guide vanes 172. The primary bypass air A2 then continues downstream to generate the primary propulsion flow, or first thrust flow S1. Most of the net thrust generated by the turbine engine 100 is produced by the first thrust flow S1.

[0054] Engine air A3 is directed or directed into inlet duct 187 and enters inlet duct 187 through engine inlet 189. Flowing downstream through inlet duct 187, engine air A3 flows over the intermediate fan blades 192 of intermediate fan 190 and is compressed by the rotating intermediate fan blades 192. After flowing over the intermediate fan blades 192, engine air A3 is split by splitter 178 into a third airflow (third portion air, referred herein as secondary bypass air A4) and a fourth airflow (fourth portion air, referred herein as core air A5). Core air A5 is directed or directed into the upstream section of core duct 140, or more specifically, into core inlet 141. Core air A5 flows through core duct 140 (as discussed above) to generate combustion gases A7 and exits core duct 140 through core air exhaust nozzle 143 to generate core airflow, also referred to as second thrust flow S2.

[0055] Secondary bypass air A4 is directed or directed into fan duct 181 and enters fan duct 181 through fan duct inlet 183. Secondary bypass air A4 flows through fan duct 181 generally in the axial direction A and exits fan duct 181 through fan duct inlet 183 to generate a third flow, also referred to as the third thrust flow S3. The third thrust flow S3 is a small fraction of the secondary airflow that increases fluid energy to generate total propulsion system thrust. In some embodiments, the pressure ratio of the third flow is higher than that of the primary propulsion flow (e.g., bypass or propeller-driven propulsion flow). Thrust can be generated by a dedicated nozzle or by mixing the secondary airflow with the primary propulsion flow or core airflow (e.g., into a common nozzle). In some embodiments, the operating temperature of the secondary airflow is lower than the engine's maximum compressor discharge temperature. Furthermore, in some embodiments, aspects of the third flow (e.g., airflow characteristics, mixing characteristics, or exhaust characteristics), and thus its percentage contribution to total thrust, are passively adjusted during engine operation, or can be purposefully modified using engine control features (such as fuel flow, motor power, variable stator, variable inlet guide vanes, valves, variable exhaust geometry, or fluid characteristics) to adjust or improve overall system performance across a wide range of potential operating conditions.

[0056] Figure 1The turbine engine 100 shown and discussed herein (e.g., a non-ducted fan engine) is provided by way of example only. In other embodiments, any other suitable engine may be used with aspects of this disclosure. For example, in other embodiments, the engine may be any other suitable gas turbine engine, such as a high-bypass turbofan engine, a turboshaft engine, a turboprop engine, a turbojet engine, etc. In this way, in other embodiments, the gas turbine engine may have other suitable configurations, such as other suitable numbers or arrangements of shafts, compressors, turbines, fans, etc. Furthermore, although turbine engine 100 is shown as a geared variable-pitch turbofan engine, in other embodiments, turbine engine 100 may be a direct-drive turbine engine or may be a fixed-pitch turbine engine. In other embodiments, the primary fan 150 and the fan guide vane array 170 may be ducted or shielded, including a nacelle or shield that circumferentially surrounds one or both of the primary fan 150 and the fan guide vane array 170, either jointly or separately. Furthermore, in alternative embodiments, aspects of this disclosure may be incorporated into or otherwise used with any other type of engine, such as a reciprocating engine.

[0057] The turbine engine 100 discussed herein is suitable for use on aircraft. Suitable aircraft include, for example, airplanes and unmanned aerial vehicles (UAVs). In other embodiments, the turbine engine can be any other turbine engine, such as an industrial turbine engine incorporated into a power generation system, or a marine turbine engine on a ship or other vessel.

[0058] Figure 2 This is a cross-sectional view of a portion of the inlet duct 187, including the intermediate fan blades 192, showing... Figure 1 Detail 2. As mentioned above, the fan shroud 174 ( Figure 1The fan housing 174 partially defines the inlet duct 187 and circumferentially surrounds the intermediate fan blade 192. More specifically, the fan housing 174 may include one or more housings or housing segments to define the inlet duct 187. In the depicted embodiment, the fan housing 200 is positioned radially outside the intermediate fan blade 192. The fan housing 200 is axially positioned to surround the intermediate fan blade 192 in a surrounding relationship. Each of the intermediate fan blades 192 includes a tip 198, and the fan housing 200 has an inner radial surface 212. The intermediate fan 190 and the fan housing 200 are positioned relative to each other to define a gap G (or clearance) between the fan housing 200 and the intermediate fan blades 192, and more specifically, between the inner radial surface 212 of the fan housing 200 and the tip 198 of each intermediate fan blade 192. The fan housing 200 may be part of a blade receiving system for retaining a broken blade or blade fragment therein. The fan housing 200 may be formed of a composite material. The fan housing 200 can be a composite component, and more specifically, a composite housing.

[0059] In the depicted embodiment, the fan housing 200 is connected to an adjacent housing (or housing segment) that also defines the inlet duct 187 or a portion thereof. More specifically, the fan housing 200 abuts against an upstream housing 202 and a downstream housing 204. The upstream housing 202 and the downstream housing 204 are depicted having acoustic panels, and more specifically, an upstream acoustic panel 206 and a downstream acoustic panel 208 are respectively fixed to one of the upstream housing 202 and the downstream housing 204. However, the acoustic panels may be omitted.

[0060] Figure 3A This is a schematic diagram of the fan housing 200. (As shown) Figure 3A As can be seen, the fan housing 200 is annular about the longitudinal centerline axis 101. The fan housing 200 can be symmetrical, defining a circular opening 222, when the fan housing 200 is mounted on the turbine engine 100 ( Figure 1 When in the middle, the middle fan is 190 ( Figure 1 It is located in opening 222. Figure 3A In the depicted embodiment, the fan housing 200 is a single, single component in the circumferential direction C. The fan housing 200 can be a continuous, unbroken structure in the circumferential direction C, and it can be a continuous annular structure. As described above, the fan housing 200 is a composite component, and... Figure 3A The depicted fan housing 200 can be formed from a single composite segment 230 having an annular shape. Figure 3B The composite section 230 shown will be more specifically referred to as the annular composite section 232.

[0061] Figure 3B This is a schematic diagram of another fan housing 240. Figure 3B The fan housing 240 shown is an alternative structure for the fan housing that can be used in place of the fan housing 200. Unless otherwise stated, the discussion of the fan housing 200 applies to... Figure 3B The fan housing 240 shown can be used in the same or similar manner as the fan housing 200 discussed herein. In this embodiment, the fan housing 240 is formed by a plurality of segments (a plurality of circumferential segments 242) in the circumferential direction C. Each of these circumferential segments 242 has an arcuate shape and can be joined together using suitable attachment means (such as fasteners) to form an annular fan housing 240. Figure 3B Four circumferential segments 242 are depicted, but other numbers of segments can be used. Each of these circumferential segments 242 can be made of a composite material and can be a composite segment 230 with an arcuate shape. Therefore, Figure 3B The fan housing 240 shown is formed by a plurality of composite segments 230, and each of these composite segments 230 will be more specifically referred to as an arcuate composite segment 234. Reference numeral 230 is used herein to refer to either the annular composite segment 232 or the arcuate composite segment 234.

[0062] Figure 4 This is a cross-sectional view of the fan housing 200, and more specifically, a cross-sectional view of the composite section 230 (e.g., annular composite section 232). The composite section 230 includes a matrix 236 and a plurality of circumferential reinforcing fiber bundles 250 embedded in the matrix 236. Each circumferential reinforcing fiber bundle 250 extends in the circumferential direction C of the composite section 230 and has a plurality of undulations 252 in the circumferential direction C. As the circumferential reinforcing fiber bundles 250 extend in the circumferential direction, the circumferential reinforcing fiber bundles 250 also have alternating radial inward and outward orientations to produce the plurality of undulations 252. Thus, the circumferential reinforcing fiber bundles 250 have a zigzag pattern or alternating pattern extending in the circumferential direction C. The circumferential reinforcing fiber bundles 250 are depicted as having a sinusoidal pattern extending in the circumferential direction C. The method of forming the composite section 230 can result in undulations having other shapes and arrangements. For example, these shapes and arrangements can have different segments between adjacent peaks 254 and valleys 256 of the undulating pattern, such as straight or curved shapes between adjacent peaks 254 and valleys 256. These shapes and arrangements can also be regular repeating patterns, for example, alternating patterns of multiple undulations 252 that are uniform in the circumferential direction C, with a constant spacing between adjacent peaks 254 and valleys 256, and the amplitude of the peaks 254 and valleys 256 is constant. Alternatively, the alternating pattern can have a random arrangement.

[0063] like Figure 4As depicted, each undulation 252 of the circumferential reinforcing fiber bundle 250 has an amplitude extending in the radial direction R. The dimensions of the undulation 252 are designed such that the length of each circumferential reinforcing fiber bundle 250 is longer than the circumferential length of the composite segment 230. For example, the length of each circumferential reinforcing fiber bundle 250 may be from one percent (1%) to ten percent (10%) longer than the circumferential length of the composite segment 230.

[0064] This fiber pattern of the circumferentially reinforced fiber bundles 250 allows the matrix 236 to expand and contract with temperature changes in the fan housing 200. For example, Figure 4 The fan housing 200 shown is a composite material and can be made of PMC material. In this case, the matrix 236 is a polymer, and the circumferential reinforcing fiber bundle 250 can be formed from one or more of the various reinforcing fiber bundles discussed above (such as carbon fiber). When the circumferential reinforcing fiber bundle 250 is formed of carbon fiber, it provides strength, particularly impact strength, to the fan housing 200, allowing it to act as a containment barrier for the blade housing system, holding broken blades or blade fragments and preventing them from being ejected through the fan housing 200. However, as discussed above, carbon fiber (or other fibers used for the circumferential reinforcing fiber bundle 250) has a low coefficient of thermal expansion (CTE). In contrast, the polymer matrix can have a relatively high CTE. As used herein, a low CTE can be 1 x 10⁻⁶. -6 CTE is inch / inch Fahrenheit (in / (in℉)) or lower. Similarly, as used herein, a high CTE can be two or more times that amount (such as five times or more), or even an order of magnitude or more higher, such as 2 x 10⁻⁶. -6 Inches / inches Fahrenheit (in / (in℉)) or higher, 5x10 -6 Inches / inches Fahrenheit (in / (in℉)) or higher, or 10x10 -6 CTE of inch / inch Fahrenheit (in / (in ℉)) or higher.

[0065] In the fiber pattern without undulations 252, circumferentially reinforcing fiber bundles constrain the polymer matrix, preventing the matrix from expanding as the temperature rises. When the intermediate fan blade 192 ( Figure 2 When formed from similar materials (e.g., composite materials), the intermediate fan blades 192 also have a low CTE, thereby limiting radial growth due to temperature increases, and thus, a tight gap (gap G) can be maintained throughout the entire operating envelope. Figure 2In some embodiments, the intermediate fan blade 192 is formed of a different material than the fan housing 200. For example, the intermediate fan blade 192 may be formed of a material (such as a metallic material) having a higher CTE than the composite section without undulations. To accommodate the radial thermal growth of the intermediate fan blade 192 during operation, the clearance G at low temperatures (such as the ambient temperature or room temperature corresponding to assembly, for example, 70 degrees Fahrenheit (70°F) (21 degrees Celsius (21°C))) is much larger than the clearance at operating temperatures. For example, such operating temperatures may be 300 degrees Fahrenheit (300°F) (260 degrees Celsius (260°C)) or higher. Therefore, this large clearance G limits the engine operating efficiency at lower temperatures.

[0066] In the fiber pattern discussed herein, the undulations 252 impart additional length to the circumferential reinforcing fiber bundles 250. Therefore, at least initially, the circumferential reinforcing fiber bundles 250 do not constrain the matrix 236, thereby allowing the matrix material of the composite section to rise in temperature from ambient or assembly temperature to the intermediate fan 190 (…). Figure 2 The fan housing 200 expands circumferentially at operating temperatures. The fan housing 200 is assembled within the fan shroud 174 to allow radial movement of the fan housing 200, and therefore, as the circumference of the fan housing 200 increases, the fan housing 200 also moves radially outward. For the fiber pattern discussed herein, it can be based on the intermediate fan blade 192 (… Figure 2 The expected growth of the matrix 236 is controlled to manage radial growth, thereby providing better porosity G throughout the operating envelope. The dimensions of the undulation 252 can be designed such that the length of each circumferential reinforcing fiber bundle 250 allows for thermal expansion of the matrix 236 to maintain porosity G during turbine engine operating conditions. Operating conditions can range from -70 degrees Fahrenheit to 700 degrees Fahrenheit.

[0067] Fan housing 200 and intermediate fan 190 ( Figure 1 The example provided is for illustrative purposes only. The fiber patterns discussed herein can be used in other applications (including turbine engines 100). Figure 1 Other composite housing structures used in other locations within the compressor blade 116 are employed together, for example, around the compressor blade 116. Figure 1 ) core shell 107 ( Figure 1 In this configuration, the housing and the structure enclosed by the housing (e.g., the rotor) are made of different materials. As mentioned above, in other embodiments, the fiber pattern discussed herein can be used in conjunction with other composite housing structures used in other engines or rotating machines. One such example includes other gas turbine engines, such as high-bypass turbofan engines, where the primary fan 150 and the fan guide vane array 170 are ducted or shielded. The intermediate fan 190 is an example of a rotor, and more specifically, includes a central hub (e.g., Figure 1Multiple airfoil elements extending radially from the disk 194 (e.g., Figure 1 An example of a rotating airfoil assembly (intermediate fan blade 192).

[0068] like Figure 4 As depicted, the circumferential reinforcing fiber bundles 250 can be arranged in a plurality of fiber layers in the radial direction. Each of these fiber layers may include a plurality of undulations 252, and in the depicted embodiment, the circumferential reinforcing fiber bundles 250 have a uniform undulation pattern in the plurality of layers and also in the circumferential direction C. The specific form of the layers may depend on the layup method of the circumferential reinforcing fiber bundles 250 or the prefabricated structure; similarly, the method for generating the plurality of undulations 252 may vary depending on the layup method of the prefabricated structure.

[0069] Figure 5 This is a flowchart of the process for manufacturing the composite segment 230. The method includes, in step S10, laying or otherwise placing a plurality of reinforcing fiber bundles (including circumferential reinforcing fiber bundles 250). Figure 4 ), to form undulations 252 ( Figure 4 Various methods can be used to lay up reinforcing fiber bundles, and some examples of forming the undulations 252 are further discussed below. For example, the method may include winding multiple reinforcing fiber bundles around a mandrel. The reinforcing fiber bundles can move axially as the mandrel rotates to form multiple plies or layers. Each ply comprises multiple fiber bundles. When applied using a mandrel, the undulations 252 are primarily in the circumferential direction C (…). Figure 4 Oriented in the axial direction A, but also in the axial direction A. Figure 3A It has components or forms an angle.

[0070] Multiple layups can also be laid manually (i.e., by hand) or using automated processes, including automated layup systems. Automated layup systems and corresponding automated processes can be, for example, automated tape layup (ATL) systems, automated fiber placement (AFP) systems, thermoplastic fiber / tape placement (TTP) systems, pick-and-place systems, etc. Other methods can be used, including weaving or knitting methods. Two-dimensional (2D) woven fabrics can be woven, and then 2D woven fabric sheets can be laid up to form multiple layups. Other weaving methods include weaving three-dimensional (3D) woven fabrics.

[0071] In step S20, the method includes forming or preparing a preform, and more specifically, forming or preparing an initial preform. The initial preform can be formed by laying reinforcing fiber bundles, and this step, or a portion thereof, can be performed as part of a laying process (step S10). When using a woven fabric (2D woven fabric or 3D woven fabric), the initial preform can be formed using one or more woven fabrics. In some embodiments, when using a 3D woven fabric, the 3D woven fabric can be near-net-shape. This step may include, for example, laying multiple woven fabrics or otherwise positioning multiple woven fabrics relative to each other to form the initial preform. In step S30, the initial preform is shaped to form a shaped preform. Shaping the initial preform may include, for example, shaping the initial preform using a die-cutting tool. Suitable shaping processes may include vacuum forming or other shaping processes to impart shape to the initial preform. The shaped preform can form the final preform, but alternatively, additional machining and manufacturing processes (such as adding inserts) can be performed on the shaped preform to form the final preform of the composite component.

[0072] In step S40, a matrix material is introduced into the preform. For example, after the preform is completed (i.e., the final preform), the matrix material can be injected into the preform in step S40 to create an infiltrated (or impregnated) preform. When the composite part is a polymer matrix composite, the polymer and / or resin can be pumped, injected, or otherwise provided to a mold or cavity in this step to infiltrate or impregnate the dry fibers. For example, this step can be performed in conjunction with step S30 when using resin transfer molding (RTM). Depending on the matrix material, other infiltration treatments can be used in this step. The matrix material can be introduced in other ways. As described above, the preform can be formed using prepreg fiber bundles to introduce the matrix material, and in such embodiments, the matrix material is introduced when the reinforcing fiber bundles are woven into the preform (step S10) or when the reinforcing fiber bundles are otherwise laid out. When using prepreg fiber bundles, the explicit step of injecting resin material can be omitted.

[0073] The method continues in step S50 to cure the infiltrated preform to bond the composite material, and more specifically, the matrix, together to form a composite component. The curing process depends on the material and may include coagulating or otherwise hardening the matrix material surrounding the fiber bundles within the preform. For example, when the matrix material is a polymer, curing may include coagulating and chemically crosslinking the polymer chains. Curing the infiltrated preform may include several treatments. For example, the infiltrated preform can be thinned and cured by exposing it to elevated temperatures and pressures in an autoclave. The infiltrated preform may also undergo one or more further treatments, such as burn-off cycles and densification treatments. Curing step S50 may be combined with step S40, such as when the matrix material is injected into the final preform in a molten state and the curing step includes cooling the matrix material.

[0074] Furthermore, the composite component can be finished as needed. Finishing can define the final shape or profile of the composite component. Additionally, the composite component can be coated with one or more suitable coatings, such as an environmental barrier coating (EBC) or a polyurethane surface coating.

[0075] Figure 6A and Figure 6B This is a schematic diagram illustrating a three-dimensional fiber weaving pattern that can be used to form a woven fabric for forming composite segments 230 ( Figure 3A and Figure 3B Prefabricated components. To clearly distinguish them from other embodiments, Figure 6A and Figure 6B The woven fabric depicted in this paper is referred to as 3D woven fabric 300. Figure 6B It is along Figure 6A The image shows a cross-sectional view taken along lines 6B-6B. As described above, the composite component can be formed from a plurality of reinforcing fibers, and more specifically, from a plurality of reinforcing fiber bundles 302. The plurality of reinforcing fiber bundles 302 are woven together to form a 3D woven fabric 300. The plurality of reinforcing fiber bundles 302 include a plurality of first fiber bundles, which in this embodiment are a plurality of warp fiber bundles 310. The plurality of reinforcing fiber bundles 302 also include a plurality of second fiber bundles, which in this embodiment are a plurality of weft fiber bundles 320. The weft fiber bundles 320 are oriented transversely to the warp fiber bundles 310, and in the depicted embodiment, the warp fiber bundles 310 and the weft fiber bundles 320 are oriented substantially orthogonally to each other. Thus, the 3D woven fabric 300 includes a warp direction Wp (also referred to as a first direction) and a weft direction Wf (also referred to as a second direction). The warp fiber bundles 310 extend in the warp direction Wp, and the weft fiber bundles 320 extend in the weft direction Wf.

[0076] In the depicted embodiment, the 3D woven fabric 300 is a three-dimensional woven fabric, and the 3D woven fabric 300 also includes a thickness direction t. The thickness direction may also be referred to as the z-direction. Warp fiber bundles 310 may be arranged relative to each other to form a plurality of warp fiber layers 312 in the thickness direction t and a plurality of warp fiber rows 314 in the weft direction Wf. Figure 6A and Figure 6B The image depicts three warp fiber layers 312, but the 3D woven fabric 300 may include any other number of warp fiber layers 312, including more than three warp fiber layers 312.

[0077] During the weaving process, the warp fiber bundle 310 can be kept taut in the warp direction Wp, and one of the weft fiber bundles 320 is passed through or pulled through it. A shuttle (not shown) can be used to pull one of the weft fiber bundles 320 through the warp fiber bundle 310. The shuttle can pass through the warp fiber bundle 310 in a first direction and then in the opposite direction at different heights in the thickness direction, thereby forming a plurality of weft fiber layers 322 in the thickness direction t. One of the weft fiber bundles 320 can continuously pass through at least a portion of the thickness of the 3D woven fabric 300, and one of the weft fiber bundles 320 can include a portion extending in the thickness direction t, which may be referred to as a turning portion in some embodiments. Thus, this portion of the weft fiber bundle may be referred to herein as a turning portion 324. The warp fiber bundles 310 can be moved relative to each other to make room for one of the weft fiber bundles 320 to pass through the space. The warp fiber bundles 310 can be moved relative to each other in different ways to produce different patterns. In this manner, weaving a 3D woven fabric 300 includes positioning warp fiber bundles 310 (e.g., keeping the warp fiber bundles 310 stationary under tension), then laying weft fiber bundles 320 (e.g., pulling the weft fiber bundles 320 across and inserting them above and below the corresponding warp fiber bundles 310), and repeating this process until the 3D woven fabric 300 is formed. The weft fiber bundles 320 may be arranged relative to each other to form a plurality of weft fiber layers 322 in the thickness direction t and a plurality of weft fiber rows 326 in the warp direction Wp.

[0078] The 3D woven fabric 300 also includes multiple interlocking fiber bundles 330 (also known as Z-woven fiber bundles). The interlocking fiber bundles 330 are additional warp fiber bundles that are guided through the thickness of the 3D woven fabric 300 during weaving to stitch the reinforcing fiber bundles 302 together. The interlocking fiber bundles 330 are woven to extend between two or more weft fiber layers 322. Different fiber patterns can be used for the interlocking fiber bundles 330. Figure 6A and Figure 6BThe first interlocking fiber pattern shown is a positive interlocking pattern, and the interlocking fiber bundle 330 is referred to herein as a positive interlocking fiber bundle 332. In this pattern, the positive interlocking fiber bundle 332 extends substantially in a direction orthogonal to the warp direction Wp, which in the depicted embodiment is the thickness direction t. Like the weft fiber bundle 320, the interlocking fiber bundle 330 (e.g., the positive interlocking fiber bundle 332) may include a turning portion 334. In the depicted embodiment, the turning portion 334 of the positive interlocking fiber bundle 332 is positioned to form an alternating pattern between each warp fiber column 314. In the depicted embodiment, the positive interlocking fiber bundle 332 extends through the thickness of the 3D woven fabric 300 and may be referred to as a full-thickness interlocking fiber bundle, but other thicknesses may be used.

[0079] Figure 6C The second interlocking fiber pattern shown is an angle interlocking pattern, and more specifically, an interlayer angle interlocking pattern. Figure 6C From and Figure 6B A cross-sectional view of the woven fabric taken from a similar perspective. The interlocking fiber bundle 330 is referred to in this embodiment as an angled interlocking fiber bundle 336. The angled interlocking fiber bundle 336 does not extend orthogonally through the 3D woven fabric 300, but rather forms an angle relative to the warp direction Wp. In the depicted embodiment, the angled interlocking fiber bundle 336 extends through adjacent weft fiber layers 322 in an alternating or sinusoidal pattern to interlock these adjacent layers with each other, wherein an angle is formed between adjacent turning portions 334 of the angled interlocking fiber bundle 336. The turning portions 334 of the angled interlocking fiber bundle 336 are located on every other weft fiber row 326, but in other embodiments, two or more weft fiber rows 326 may be between adjacent turning portions 334 of the angled interlocking fiber bundle 336. In other embodiments, the angled interlocking fiber bundle 336 may extend through more than two adjacent weft fiber layers 322. For example, as Figure 6D As shown, the interlocking fiber bundle 330 is a full-thickness interlocking fiber bundle, which is referred to herein as the full-thickness angled interlocking fiber bundle 338. Figure 6D From and Figure 6B A cross-sectional view of the woven fabric taken from a similar perspective. For clarity, Figure 6C and Figure 6D The 320-degree weft fiber bundle is omitted.

[0080] Figure 7 It can be used to form the composite segment 230 discussed in this paper. Figure 3A and Figure 3B A schematic cross-sectional view of a portion of a 3D woven fabric 300. For clarity, from... Figure 7The interlocking fiber bundle 330 is omitted. When using 3D woven fabrics (such as the 3D woven fabric 300 discussed above), the fabric (especially the interlocking fiber bundle 330) Figure 6A The three-dimensional properties of the 3D woven fabric 300 may limit its manipulation during the lamination process to form undulations 252 when formed as a preform. Figure 4 The ability to convex and convex portions. In some embodiments, the convex portion 252 may be introduced during the weaving process. The convex portion 252 may be imparted during the weaving process by using a catch cord 340. For example, during the weaving process, the convex portion 252 is formed in the warp fiber bundle 310 by offsetting the weft fiber layer 322 at different heights in the thickness direction of the extended pattern (such as an convex pattern). In this embodiment, the warp fiber bundle 310 is a circumferentially reinforcing fiber bundle 250 ( Figure 4 When the weft fiber bundle 320 and the warp fiber bundle 310 are interwoven in an undulating pattern, additional length is introduced into the warp fiber bundle 310.

[0081] To create an undulating pattern and offset the weft fiber layer 322 in the thickness direction, the weaving process includes the use of multiple tripwires 340. The tripwires 340 support the weft fiber bundles 320 during the weaving process and are subsequently removed, as will be discussed below. The tripwires 340 are preferably formed of a material that can be easily removed once the weaving process is complete. The tripwires 340 can be formed of polymeric materials (such as nylon) and can be polymer threads. The tripwires 340 can also be formed of metal (such as steel) and can be metal wires.

[0082] The weaving process of the 3D woven fabric 300 includes placing a plurality of tripwires 340 at different heights in the thickness direction t. A weft fiber layer 322 includes a top weft fiber layer, which will be referred to herein as the supported layer 350. The weft fiber bundles 320 of the supported layer 350 are supported by different tripwires 340 to form an undulating pattern. More specifically, the plurality of tripwires 340 includes an upper tripwire 342 and a lower tripwire 344. A first fiber bundle 352 of the supported layer 350 is supported by the upper tripwire 342, and a second fiber bundle 354 of the supported layer 350 is supported by the lower tripwire 344. Weft fiber rows 326 are offset from each other by different distances in the thickness direction t, and more specifically, adjacent weft fiber rows 326 are offset from each other in the thickness direction t. While the tripwires 340 can be used to offset only a portion of the weft fiber bundles 320 in the weft fiber rows 326, in the depicted embodiment, all weft fiber bundles 320 in the weft fiber rows 326 are offset.

[0083] The offset in the weft fiber row 326 can be controlled to change the length of the warp fiber bundle 310 and the size of the undulation 252. While this offset can be controlled by changing (i.e., increasing or decreasing) the spacing between the tripwires 340, it can also be controlled by supporting the supported layer 350 with different tripwires 340. The plurality of tripwires 340 includes an intermediate tripwire 346 between the upper tripwire 342 and the lower tripwire 344, and the third fiber bundle 356 of the supported layer 350 is supported by the intermediate tripwire 349. The third fiber bundle 356 is located in the extension direction between the first fiber bundle 352 and the second fiber bundle 354, as shown... Figure 7 The direction of extension is depicted as the warp direction Wp. After weaving, in some embodiments, in step S20 (… Figure 5 In step S30, an initial preform is formed or in step S30 ( Figure 5 After the preform is formed in the 320, the tripwire 340 can be removed, for example, by pulling the tripwire 340 out of the weft fiber bundle 320.

[0084] Figure 8A It can be used to form the composite segment 230 discussed in this paper. Figure 3A and Figure 3B The diagram shows a schematic cross-sectional view of the layers and stacks of the composite layup. As discussed above, multiple reinforcing fiber bundles 410 can be laid on a forming tool 420 (such as a mandrel or table) to form multiple layups including a first layup 412, a second layup 414 and a third layup 416. Figure 8A Three layups are shown to illustrate the method discussed herein, but other numbers of layups may also be used. Multiple layups can be laid as individual reinforcing fiber bundles 410, but in some embodiments, the reinforcing fiber bundles 410 can be woven into a woven fabric, and more specifically, into a 2D woven fabric. Multiple layups can be laid by placing multiple 2D woven fabric sheets on top of each other. Figure 8A The reinforcing fiber bundle 410 shown can be the circumferential reinforcing fiber bundle 250 discussed above, and Figure 8A The view depicted is in the axial direction A of the precast component. Figure 3A and Figure 3B Observed on the surface. Strips or layups of the resin film (referred to herein as resin strip 430) are periodically interspersed between multiple layups. Resin strip 430 may be formed from the same material (such as the same resin) used to form the matrix material introduced in step S40, and resin strip 430 is then cured in the curing step ( Figure 5 During step S50, it becomes part of the matrix.

[0085] like Figure 8AAs depicted, for example, a first resin strip 442 is placed on a forming tool 420, and then a second resin strip 452 is placed on the forming tool 420, the second resin strip 452 being spaced apart from the first resin strip 442 in the circumferential direction C. While the first resin strip 442 and the second resin strip 452 are depicted as being placed directly on the forming tool 420, alternative arrangements can be used. For example, the first resin strip 442 and the second resin strip 452 can be placed indirectly on the forming tool 420, such as by placing them on a fiber preform (such as an additional layup reinforcing fiber bundle 410) that serves as a bottom layer or inner layer (i.e., the first layer), and the first resin strip 442 and the second resin strip 452 can be placed directly on the bottom layer or inner layer. Each of the plurality of resin strips has a longitudinal direction, in Figure 8A In the process, the longitudinal direction enters and exits the page. The circumferential direction C is a direction transverse to the longitudinal direction, such as a direction orthogonal to the longitudinal direction. Therefore, multiple resin strips 430 are placed on the forming tool 420 in a spaced-apart manner (such as circumferentially spaced). The multiple resin strips 430 can be placed parallel to each other. When the preform (and subsequently the composite section 230) has an arcuate or annular shape, the multiple resin strips 430 can be oriented such that the longitudinal direction of each of the multiple resin strips 430 is parallel to the axial direction of the preform. Each of the multiple resin strips 430 also includes a thickness direction perpendicular to the longitudinal direction in a certain direction. The following discussion will refer to the circumferential direction C and the axial direction A ( Figure 3B However, this method is also applicable to preforms and composite segments 230 that do not have an arcuate or annular shapes, and for these other shapes, the circumferential direction C and the axial direction A can be other directions, such as the length direction and the width direction. Similarly, for preforms and composite segments 230 that do not have an arcuate or annular shapes, the circumferential reinforcing fiber bundle 250 can be a transverse reinforcing fiber bundle extending in a transverse direction (such as the length direction or the width direction).

[0086] Next, a first layup 412 of the reinforcing fiber bundle 410 is laid on the forming tool 420, and on top of the first resin strip 442 and the second resin strip 452. Then, a third resin strip 444 is placed on the first layup 412 at the same circumferential position as the first resin strip 442, above the first resin strip 442. Similarly, a fourth resin strip 454 is placed above the second resin strip 452. Thus, multiple resin strips 430 are placed on the first resin strip 442 and the second resin strip 452 in a spaced-apart manner. Then, a second layup 414 of the reinforcing fiber bundle 410 is laid, and this process is repeated for the fifth resin strip 446, the sixth resin strip 456, and the third layup 416. The first resin strip 442, the third resin strip 444, and the fifth resin strip 446 are placed above each other at the same circumferential position to form a first stack 440 of resin strips 430. Multiple resin strips 430 are interposed between multiple layups of reinforcing fiber bundles 410. Similarly, second resin strips 452, fourth resin strips 454, and sixth resin strips 456 are placed above each other at the same circumferential position to form a second stack 450 of resin strips 430. Thus, multiple resin strips 430 are arranged to form multiple stacks of resin strips 430 spaced apart from each other (and more specifically, circumferentially spaced apart from each other) (e.g., a first stack 440 of resin strips 430 and a second stack 450 of resin strips 430). During curing ( Figure 5 Following step S50, the first stack 440 and the second stack 450 create undulations 252 (e.g., peaks 254) in the circumferential reinforcing fiber bundle 250. Valleys 256 may be formed in the span between the stacks of resin strips 430 (e.g., the first stack 440 and the second stack 450). The thickness of the resin strips 430 and the spacing between the stacks of resin strips 430 (e.g., the first stack 440 and the second stack 450) can be controlled to produce the desired amplitude of the undulations 252 discussed above.

[0087] Figure 8B It can be used to form the composite segment 230 discussed in this paper. Figure 3A and Figure 3B A schematic cross-sectional view of the composite layup and stack. Figure 8B The process and stack shown are similar to those in the reference above. Figure 8A The subject of discussion. Unless otherwise expressly stated, Figure 8A The discussion also applies here, where similar reference numerals represent the same or similar parts and features. For example... Figure 8AAs shown, a first resin strip 442 is placed on a forming tool 420, and then a second resin strip 452 is placed on the forming tool 420 (directly or indirectly), the second resin strip 452 being spaced apart from the first resin strip 442 in the circumferential direction C. Then, a first layup 412 of the reinforcing fiber bundle 410 is laid on the forming tool 420, above the first resin strip 442 and the second resin strip 452. Subsequent layups of the reinforcing fiber bundle 410 (e.g., second layup 414 and third layup 416) are laid on top of each other, rather than placing additional resin strips 430 between the subsequent layups of the reinforcing fiber bundle 410 (e.g., second layup 414 and third layup 416). In this embodiment, a plurality of resin strips 430 (e.g., first resin strip 442 and second resin strip 452) placed at intervals on the forming tool 420 create undulations 252 (e.g., peaks 254) in the circumferential reinforcing fiber bundle 250.

[0088] Figure 8C It can be used to form the composite segment 230 discussed in this paper. Figure 3A and 3B A schematic cross-sectional view of the composite layup and stack. Figure 8C The process and stack shown are similar to those in the reference above. Figure 8A The subject of discussion. Unless otherwise expressly stated, Figure 8A The discussion also applies here, where similar reference numerals represent the same or similar parts and features. Figure 8A In this process, one or more resin strips 430 are used to form stacks, such as by intercalation between multiple layups of reinforcing fiber bundles 410. Multiple stacks (e.g., a first stack 440 and a second stack 450) are spaced apart from each other to create undulations 252 with valleys 256 therebetween. Instead of using multiple resin strips 430, multiple resin sheets 460 are used. Multiple resin sheets 460 are intercalated between multiple layups. Multiple resin sheets 460 form a continuous layer in the circumferential direction C between the forming tool 420 and the first layup 412, and between adjacent layups (such as between the first layup 412 and the second layup 414, and between the second layup 414 and the third layup 416). Although Figure 8C Each ply is depicted as being separated by one of a plurality of resin sheets 460, but other arrangements may be used, in which some plies are positioned in direct contact with each other, rather than having resin sheets between each ply. Additionally, as discussed above, a bottom or inner layer of reinforcing fiber bundles 410 may be used.

[0089] like Figure 8CAs depicted, for example, a first resin sheet 462 is placed on a forming tool 420. Then, a first layup 412 of the reinforcing fiber bundle 410 is laid on the forming tool 420, and on top of the first resin sheet 462. Next, a second resin sheet 464 is placed on the first layup 412, and then a second layup 414 of the reinforcing fiber bundle 410 is laid. This process is repeated for a third resin sheet 466 and a third layup 416. Multiple resin sheets 460 are interposed between multiple layups of the reinforcing fiber bundle 410. The additional resin sheets 460 increase the length of the circumferential reinforcing fiber bundle 250, and during curing (… Figure 5 During step S50, the resin sheet 460 flows, thereby allowing the circumferential reinforcing fiber bundle 250 to produce undulations 252 (e.g., peaks 254) and valleys 256 (e.g., less than one millimeter between adjacent undulations 252, such as one hundred micrometers or less between adjacent undulations 252) on a microscale.

[0090] Figure 9 This is a top view of the 2D woven fabric 500, which can be used to form the composite segment 230 discussed in this paper. Figure 3A and Figure 3B This can be used in the layering process discussed above with reference to Figure 8. During the weaving process, the warp fiber bundle 510 can be kept taut in the warp direction Wp, and one of the weft fiber bundles 520 is passed through or pulled through it. A shuttle (not shown) can be used to pull one of the weft fiber bundles 520 through the warp fiber bundle 510. The shuttle can pass through the warp fiber bundle 510 in a first direction and then reverse to pass through the warp fiber bundle 510 at different positions in the warp direction Wp. The warp fiber bundles 510 can be moved relative to each other to make room for one of the weft fiber bundles 520 to pass through that space. The warp fiber bundles 510 can be moved relative to each other in different ways to produce different patterns. In this way, weaving a 2D woven fabric 500 includes positioning a warp fiber bundle 510 (e.g., such that the warp fiber bundle 510 remains stationary under tension), then laying a weft fiber bundle 520 (e.g., such that the weft fiber bundle 520 is pulled over and inserted above and below the corresponding warp fiber bundle 510), and repeating this process until a 2D woven fabric 500 is formed. Figure 9 Plain weave is depicted, but other weave patterns may be used, including, for example, twill weave and satin weave patterns. In some embodiments, the circumferential reinforcing fiber bundle 250 is the warp fiber bundle 510.

[0091] The composite section 230 discussed herein has a fiber pattern that allows for thermal expansion of the composite section 230. This composite section 230 can be used to form composite housings (e.g., fan housings 200, 240), such as housings for rotors, and more specifically, housings for rotating airfoils. When the rotor is formed of a material different from that of the composite housing, the fiber pattern allows for thermal expansion of the housing, providing, among other things, the desired clearance between the housing and the rotor throughout the operating envelope. Further aspects of this disclosure are provided by the subject matter of the following clauses.

[0092] A housing for a turbine engine includes a composite section having (i) an arcuate or annular shape and (ii) a circumferential orientation. The composite section includes a matrix and a plurality of circumferential reinforcing fiber bundles embedded in the matrix, which is formed of a matrix material. Each of the plurality of circumferential reinforcing fiber bundles extends in the circumferential direction and has a plurality of undulations in the circumferential direction to allow circumferential expansion of the matrix material of the composite section.

[0093] According to the housing described in the foregoing clause, the composite section has a radial direction, and each of the plurality of undulations has an amplitude extending in the radial direction.

[0094] The housing according to any of the foregoing clauses, wherein the plurality of undulations have a uniform alternating pattern in the circumferential direction.

[0095] According to any of the foregoing clauses, the composite segment has a circumferential length, and each of the plurality of circumferential reinforcing fiber bundles has a length, wherein the dimensions of the plurality of undulations are designed such that the length of each circumferential reinforcing fiber bundle is longer than the circumferential length of the composite segment.

[0096] The housing according to any of the foregoing clauses, wherein the composite section has an axial direction and the plurality of circumferential reinforcing fiber bundles are angled in the axial direction.

[0097] The housing according to any of the foregoing clauses, wherein the composite segment is one of a plurality of composite segments, each of the plurality of composite segments having an arcuate shape and including the matrix and the plurality of circumferential reinforcing fiber bundles embedded in the matrix, the plurality of composite segments being arranged to form an annular housing having the circumferential direction.

[0098] The housing according to any of the foregoing clauses, wherein the plurality of circumferential reinforcing fiber bundles are arranged in a plurality of layers in the radial direction.

[0099] The shell according to the foregoing clause, wherein the plurality of layers are multiple layups of a two-dimensional woven fabric.

[0100] The housing according to any of the foregoing clauses, wherein the plurality of circumferential reinforcing fiber bundles are part of a woven fabric having the plurality of undulations.

[0101] According to the shell described in the foregoing clause, the plurality of circumferential reinforcing fiber bundles are warp fiber bundles of the woven fabric.

[0102] According to any of the preceding clauses, the housing comprises a plurality of reinforcing fiber bundles, the plurality of reinforcing fiber bundles comprising a plurality of first fiber bundles and a plurality of second fiber bundles oriented transversely to the plurality of first fiber bundles, the plurality of circumferential reinforcing fiber bundles being one of the plurality of first fiber bundles or the plurality of second fiber bundles, the woven fabric being a three-dimensional woven fabric having a first direction, a second direction orthogonal to the first direction, and a thickness direction orthogonal to each of the first direction and the second direction, the plurality of first fiber bundles being arranged in the thickness direction to form a plurality of first fiber layers, and the plurality of second fiber bundles being arranged in the thickness direction to form a plurality of second fiber layers.

[0103] According to the shell described in the foregoing clause, the reinforcing fiber bundle includes a plurality of interlocking fiber bundles.

[0104] A turbine engine includes: a rotor; and a housing according to any of the preceding clauses, the housing circumferentially surrounding the rotor.

[0105] According to the preceding clause, the turbine engine wherein the rotor is formed of a metallic material and the matrix is ​​a polymer.

[0106] The turbine engine according to any of the foregoing clauses, wherein the rotor is a rotating airfoil assembly comprising a plurality of airfoils extending radially from a central hub.

[0107] According to the turbine engine described in the preceding clause, the rotating airfoil assembly is positioned relative to the housing to define a gap between the housing and the tip of the airfoil.

[0108] According to the preceding clause, the turbine engine includes a compressor section having one or more compressor rotors, the rotating airfoil assembly is one of the compressor rotors, and the airfoil is a compressor blade.

[0109] The turbine engine according to any of the foregoing clauses, wherein the turbine engine includes a fan section, the rotating airfoil assembly is a fan, and the airfoil is a fan blade.

[0110] According to any of the preceding clauses, the composite section has a circumferential length, and each of the plurality of circumferential reinforcing fiber bundles has a length, the dimensions of the plurality of undulations being designed such that the length of each circumferential reinforcing fiber bundle allows for thermal expansion of the matrix to maintain the voids during the operating conditions of the turbine engine.

[0111] According to the turbine engine described in the foregoing clause, the operating conditions are temperatures ranging from -70 degrees Fahrenheit to 700 degrees Fahrenheit.

[0112] A method for forming a preform of a composite segment for a turbine engine housing includes placing a plurality of resin strips on a forming tool and laying a plurality of reinforcing fiber bundles on the forming tool and the plurality of resin strips to form a plurality of layups. Each of the plurality of resin strips has a longitudinal direction and is spaced apart from one or more adjacent resin strips in a transverse direction transverse to the longitudinal direction. The plurality of reinforcing fiber bundles includes transverse reinforcing fiber bundles extending in the transverse direction.

[0113] The method for forming a preform according to the foregoing clauses, wherein each of the plurality of layups is a two-dimensional woven fabric.

[0114] The method of forming a preform according to any of the foregoing clauses, wherein the preform has (i) an arcuate shape or annular shape and (ii) a circumferential direction, the circumferential direction being the transverse direction, and the transverse reinforcing fiber bundles being circumferential reinforcing fiber bundles.

[0115] The method of forming a preform according to any of the foregoing clauses, wherein the preform has an axial direction, and the plurality of resin strips are oriented such that the longitudinal direction of each of the plurality of resin strips is parallel to the axial direction.

[0116] In any of the foregoing clauses, the method for forming a preform involves placing the plurality of resin strips directly onto the forming tool.

[0117] The method for forming a preform according to any of the foregoing clauses, wherein the forming tool is a mandrel.

[0118] The method of forming a preform according to any of the foregoing clauses, wherein laying the plurality of layers includes wrapping the circumferential reinforcing fiber bundle around the mandrel in the circumferential direction.

[0119] The method of forming a preform according to any of the foregoing clauses, wherein each of the plurality of layups is a two-dimensional woven fabric having warp fiber bundles and weft fiber bundles, the circumferential reinforcing fiber bundles being the warp fiber bundles of the two-dimensional woven fabric.

[0120] The method of forming a preform according to any of the foregoing clauses, wherein the plurality of resin strips are a plurality of first resin strips forming a first layer or resin strip, wherein the method further comprises placing a plurality of second resin strips on one of the plurality of layups of reinforcing fiber bundles to form a second layer or resin strip, each of the plurality of second resin strips having a longitudinal direction and being spaced apart from one or more adjacent second resin strips in the transverse direction.

[0121] The method of forming a preform according to any of the foregoing clauses, wherein one or more of the plurality of plies of reinforcing fibers are laid on the plurality of second resin strips.

[0122] The method of forming a preform according to any of the foregoing clauses, wherein each of the plurality of second resin strips is placed above a corresponding first resin strip among the plurality of first resin strips to form a plurality of stacks of resin strips.

[0123] A method of forming a preform of a composite segment for a turbine engine housing includes placing a first resin sheet on a forming tool, laying a plurality of reinforcing fiber bundles on the first resin sheet to form a first ply of reinforcing fiber bundles, placing a second resin sheet on the first ply, and laying a plurality of reinforcing fiber bundles on the second resin sheet to form a second ply. The preform has (i) an arcuate or annular shape and (ii) a circumferential direction. The plurality of reinforcing fiber bundles of the first ply include circumferential reinforcing fiber bundles extending in the circumferential direction, and the plurality of reinforcing fiber bundles of the second ply include circumferential reinforcing fiber bundles extending in the circumferential direction.

[0124] In the method for forming a preform according to the foregoing clause, the first resin sheet is placed directly on the forming tool.

[0125] The method of forming a preform according to any of the foregoing clauses, wherein the plurality of reinforcing fiber bundles of the first layup are woven into a two-dimensional woven fabric, and the plurality of reinforcing fiber bundles of the second layup are woven into a two-dimensional woven fabric.

[0126] The method of forming a preform according to any of the foregoing clauses, wherein each of the two-dimensional woven fabrics has a warp fiber bundle and a weft fiber bundle, and the circumferential reinforcing fiber bundle is the warp fiber bundle of each of the two-dimensional woven fabrics.

[0127] A method for forming a preform having (i) an arcuate or annular shape and (ii) a circumferential direction for a composite segment of a turbine engine housing, comprising placing a plurality of reinforcing fiber bundles, the plurality of reinforcing fiber bundles including a plurality of circumferential reinforcing fiber bundles, wherein each of the plurality of circumferential reinforcing fiber bundles extends in the circumferential direction.

[0128] The method of forming a preform according to any of the foregoing clauses further includes arranging the plurality of circumferential reinforcing fiber bundles in a plurality of fiber layers in the radial direction.

[0129] The method of forming a preform according to any of the foregoing clauses further includes laying multiple layers of a two-dimensional woven fabric in the radial direction.

[0130] The method of forming a preform according to any of the foregoing clauses further includes inserting a plurality of resin strips between the fiber layers or the plurality of layups to form the plurality of undulations.

[0131] The method of forming a preform according to any of the foregoing clauses, wherein the plurality of circumferential reinforcing fiber bundles are part of a woven fabric having the plurality of undulations.

[0132] The method of forming a preform according to any of the foregoing clauses, wherein the plurality of circumferential reinforcing fiber bundles are warp fiber bundles of the woven fabric.

[0133] The method of forming a preform according to any of the foregoing clauses further includes weaving the plurality of reinforcing fiber bundles to form a woven fabric.

[0134] According to the method for forming a preform as described in the foregoing clause, the plurality of reinforcing fiber bundles include a plurality of first fiber bundles and a plurality of second fiber bundles oriented transversely to the plurality of first fiber bundles, the plurality of circumferential reinforcing fiber bundles being one of the plurality of first fiber bundles or the plurality of second fiber bundles, the woven fabric being a three-dimensional woven fabric having a first direction, a second direction orthogonal to the first direction, and a thickness direction orthogonal to each of the first direction and the second direction, the plurality of first fiber bundles being arranged in the thickness direction to form a plurality of first fiber layers, and the plurality of second fiber bundles being arranged in the thickness direction to form a plurality of second fiber layers.

[0135] The method of forming a preform according to any of the foregoing clauses, wherein the reinforcing fiber bundle comprises a plurality of interlocking fiber bundles.

[0136] The method for forming a preform according to the foregoing clauses, wherein the interlocking fiber bundles are woven in a positive interlocking pattern.

[0137] The method for forming a preform according to the foregoing clauses, wherein the positive interlocking pattern extends through the thickness of the woven fabric.

[0138] The method of forming a preform according to any of the foregoing clauses, wherein the interlocking fiber bundles are woven in an angled interlocking pattern.

[0139] The method of forming a preform according to any of the foregoing clauses, wherein the angled interlocking pattern extends through adjacent fiber layers in an alternating or sinusoidal pattern to interlock these adjacent layers with each other.

[0140] The method of forming a preform according to any of the foregoing clauses, wherein the angled interlocking pattern extends through more than two adjacent fiber layers.

[0141] The method of forming a preform according to any of the foregoing clauses, wherein the angled interlocking pattern extends through the thickness of the woven fabric.

[0142] The method of forming a preform according to any of the foregoing clauses, wherein the plurality of first fiber bundles are a plurality of warp fiber bundles and the plurality of second fiber bundles are a plurality of weft fiber bundles.

[0143] The method of forming a preform according to any of the foregoing clauses, wherein the first direction is the longitudinal direction and the second direction is the latitudinal direction.

[0144] A method for forming a composite section for a turbine engine housing includes forming a preform using a preform forming method according to any of the preceding clauses, and introducing a matrix material into the preform.

[0145] The method for forming a composite segment according to the foregoing clause further includes curing the preform comprising the matrix material to generate the composite segment, wherein the plurality of circumferential reinforcing fiber bundles have a plurality of undulations in the circumferential direction.

[0146] The method of forming a composite segment according to any of the foregoing clauses further includes curing the preform comprising the matrix material, the first resin sheet and the second resin sheet to generate the composite segment, wherein the circumferential reinforcing fiber bundles of each of the first and second layups have a plurality of undulations in the circumferential direction.

[0147] The method of forming a composite segment according to any of the foregoing clauses further includes curing the preform comprising the matrix material and the plurality of resin strips to generate the composite segment, wherein the transverse reinforcing fiber bundles of the plurality of reinforcing fiber bundles have a plurality of undulations in the transverse direction.

[0148] The method for forming a composite segment according to any of the foregoing clauses, wherein the plurality of undulations includes a plurality of peaks and a plurality of valleys, the plurality of peaks being formed at lateral positions corresponding to the positioning of each of the plurality of strips.

[0149] According to any of the foregoing clauses, the method of forming composite segments includes a plurality of peaks and a plurality of valleys, wherein the plurality of peaks are formed at lateral positions corresponding to the positioning of each of the plurality of stacks of resin strips.

[0150] The method of forming a composite segment according to any of the foregoing clauses, wherein the composite segment has a radial direction, and each of the plurality of undulations has an amplitude extending in the radial direction.

[0151] The method for forming a composite segment according to any of the foregoing clauses, wherein the plurality of undulations have a uniform alternating pattern in the circumferential direction.

[0152] The method of forming a composite segment according to any of the foregoing clauses, wherein the composite segment has a circumferential length, and each of the plurality of circumferential reinforcing fiber bundles has a length, the dimensions of the plurality of undulations being designed such that the length of each circumferential reinforcing fiber bundle is longer than the circumferential length of the composite segment.

[0153] The method of forming a composite segment according to any of the foregoing clauses, wherein the preform has an axial direction and the plurality of circumferential reinforcing fiber bundles are angled in the axial direction.

[0154] The method of forming a composite segment according to any of the foregoing clauses, wherein introducing the matrix material includes injecting the matrix material into the preform.

[0155] The method of forming composite segments according to any of the foregoing clauses, wherein the plurality of reinforcing fiber bundles include prepreg fiber bundles to be incorporated into the matrix material.

[0156] The method of forming composite segments according to any of the foregoing clauses, wherein each of the plurality of strips is the same resin as the resin used to form the matrix material.

[0157] The method for forming composite segments according to any of the foregoing clauses, wherein the first resin sheet and the second resin sheet are the same resin as the resin used to form the matrix material.

[0158] A method of forming a housing for a turbine engine includes forming a plurality of composite segments according to any of the preceding clauses, and arranging the plurality of composite segments to form an annular housing having the circumferential direction.

[0159] While the foregoing description is directed to certain embodiments, other variations and modifications will be apparent to those skilled in the art and can be made without departing from this disclosure. Furthermore, features described in connection with one embodiment may be used in conjunction with other embodiments, even if not explicitly stated above.

Claims

1. A housing for a turbine engine, characterized in that, The housing includes: A composite segment having (i) an arcuate or annular shape and (ii) a circumferential direction, the composite segment comprising a matrix and a plurality of circumferential reinforcing fiber bundles embedded in the matrix formed of a matrix material, each of the plurality of circumferential reinforcing fiber bundles extending in the circumferential direction and having a plurality of undulations in the circumferential direction to allow the matrix material of the composite segment to expand circumferentially.

2. The housing according to claim 1, characterized in that, in, The composite section has a radial direction, and each of the plurality of undulations has an amplitude extending in the radial direction.

3. The housing according to claim 1, characterized in that, in, The plurality of undulations have a uniform alternating pattern in the circumferential direction.

4. The housing according to claim 1, characterized in that, in, The composite segment has a circumferential length, and each of the plurality of circumferential reinforcing fiber bundles has a length, the dimensions of the plurality of undulations being designed such that the length of each circumferential reinforcing fiber bundle is longer than the circumferential length of the composite segment.

5. The housing according to claim 1, characterized in that, in, The composite section has an axial direction, and the plurality of circumferential reinforcing fiber bundles are angled in the axial direction.

6. The housing according to claim 1, characterized in that, in, The composite segment is one of a plurality of composite segments, each of the plurality of composite segments having an arcuate shape and including the matrix and the plurality of circumferential reinforcing fiber bundles embedded in the matrix, the plurality of composite segments being arranged to form an annular shell having the circumferential direction.

7. The housing according to claim 1, characterized in that, in, The plurality of circumferential reinforcing fiber bundles are arranged in multiple layers in the radial direction.

8. The housing according to claim 7, characterized in that, in, The multiple layers are multiple layups of a two-dimensional woven fabric.

9. The housing according to claim 1, characterized in that, in, The plurality of circumferential reinforcing fiber bundles are part of a woven fabric having the plurality of undulations.

10. The housing according to claim 9, characterized in that, in, The plurality of circumferential reinforcing fiber bundles are the warp fiber bundles of the woven fabric.

Images