Flexible shroud design with variable stiffness

Abstract

Methods, apparatus, systems, and articles of manufacture are disclosed. A shroud assembly of a gas turbine engine includes a first shroud arm having a first end coupled to an outer wall and a second end coupled to a first shroud pad; and a second shroud arm having a first end and a second end, the first end coupled to the outer wall and the second end coupled to the second shroud pad, at least one of the first shroud pad or the second shroud pad moving radially outward toward the outer wall in response to a rotor blade contacting the at least one of the first shroud pad or the second shroud pad.

Description

[0001] This application is a divisional application of the invention patent application filed on June 8, 2022, with application number 202210647592.0 and invention title "Flexible Shield Design with Variable Stiffness". Technical Field

[0002] This disclosure generally relates to shields for gas turbines, and more specifically, to shield design. Background Technology

[0003] Gas turbine engines typically consist of an inlet section, compressor section, combustion section, turbine section, and exhaust section in a sequential flow order. During operation, air enters the inlet section and flows to the compressor section, where one or more axial compressors progressively compress the air until it reaches the combustion section, producing combustion gases. The combustion gases flow from the combustion section through a hot gas path defined within the turbine section and then exit the turbine section via the exhaust section. Summary of the Invention

[0004] Methods, apparatus, systems, and articles for manufacturing flexible shield designs with variable stiffness are disclosed.

[0005] Some examples provide a shield assembly for a gas turbine engine, comprising: a first shield arm having a first end and a second end, the first end being coupled to an outer wall and the second end being coupled to a first shield pad; and a second shield arm having a first end and a second end, the first end being coupled to the outer wall and the second end being coupled to a second shield pad, at least one of the first shield pad or the second shield pad moving radially outward toward the outer wall in response to rotor blades contacting at least one of the first shield pad or the second shield pad.

[0006] Some examples provide a gas turbine engine including a compressor having a compressor housing and at least one compressor blade, a combustion section, a turbine including a turbine housing and at least one turbine blade, a shaft rotatably connecting the compressor and the turbine, and a shroud assembly for at least one of the compressor or turbine, the shroud assembly including: a first shroud arm having a first end and a second end, the first end being coupled to an outer wall and the second end being coupled to a first shroud pad; and a second shroud arm having a first end and a second end, the first end being coupled to the outer wall and the second end being coupled to a second shroud pad, at least one of the first shroud pad or the second shroud pad moving radially outward toward the outer wall in response to rotor blades contacting at least one of the first shroud pad or the second shroud pad.

[0007] Some examples provide a shielding device including: a first means for reducing blade damage, the first means having a first end and a second end, the first end being coupled to an outer wall of a shielding assembly and the second end being coupled to a first shielding pad; and a second means for reducing blade damage, the second means having a first end and a second end, the first end being coupled to an outer wall and the second end being coupled to a second shielding pad, at least one of the first shielding pad or the second shielding pad moving radially outward toward the outer wall in response to rotor blades contacting at least one of the first shielding pad or the second shielding pad. Attached Figure Description

[0008] Figure 1 An example gas turbine engine is shown.

[0009] Figure 2 It shows Figure 1 The example cross-sectional side view of an example stage of a high-pressure compressor for a turbofan is shown.

[0010] Figure 3 It shows Figure 1 The example cross-sectional side view of an example stage of a high-pressure compressor for a turbofan is shown.

[0011] Figure 4 An example cross-sectional side view of the first example shield assembly is shown.

[0012] Figure 5 An example cross-sectional side view of the second example shield assembly is shown.

[0013] Figure 6 An example cross-sectional side view of the third example shield component is shown.

[0014] Figure 7 An example cross-sectional side view of the fourth example shield assembly is shown.

[0015] Figure 8 An example cross-sectional side view of the fifth example shield assembly is shown.

[0016] Figures 9A-9B An example cross-sectional side view of the sixth example shield assembly is shown.

[0017] Figure 10 It shows Figure 2 Example front view of the shield component -9.

[0018] Figure 11A-11C An example bottom view of the protective pad is shown.

[0019] Figure 12 An example bottom view of the protective pad including anti-rotation tabs is shown.

[0020] Figure 13 It shows Figure 2 An exemplary bottom perspective view of the shield assembly of -9.

[0021] Figures 14A-14B It shows Figure 2 Example 3D view of the shield assembly of -9.

[0022] Figure 15 It shows Figure 2 Example cross-sectional side view of HP compressor 114.

[0023] The accompanying drawings are not drawn to scale. Instead, the thickness of layers or regions may be enlarged in the drawings. Although the drawings show layers and regions with clearly defined lines and boundaries, some or all of these lines and / or boundaries may be idealized. In reality, boundaries and / or lines may be unobservable, mixed, and / or irregular. Generally, the same reference numerals will be used throughout the drawings and the accompanying written description to refer to the same or similar parts. As used herein, indicating that any part (e.g., layer, film, region, area, or plate) is located (e.g., positioned, situated, set, or formed, etc.) on another part in any way indicates that the referred part is either in contact with the other part or is above the other part, and one or more intermediate parts are located between them. As used herein, a connection reference (e.g., attachment, coupling, connection, and joining) may include intermediate members between elements referred to by the connection reference and / or relative movement between those elements, unless otherwise stated. Therefore, a connection reference does not necessarily imply that two elements are directly connected and / or have a fixed relationship with each other. As used in this article, the statement that any part is "in contact" with another part is defined as meaning that there is no intermediate part between the two parts. Detailed Implementation

[0024] During normal engine operation, one or more rotor blades may come into contact with the shroud. This contact (e.g., friction) between the rotor blades and the shroud leads to eventual wear of the rotor blades and / or the shroud. Throughout this contact process, it is essential to reduce frictional losses at the blade tips. Some examples provide flexible shroud designs with variable stiffness that reduce friction and improve the durability of one or more rotor blades, the shroud, and the associated engine. The examples disclosed herein increase clearance and reduce blade damage during operation, thereby lowering maintenance costs.

[0025] In the following detailed description, reference is made to the accompanying drawings, which form a part thereof, in which specific examples that can be practiced are illustrated by way of illustration. These examples are described in sufficient detail to enable those skilled in the art to practice the subject matter, and it should be understood that other examples may be used. Therefore, the following detailed description is provided to describe exemplary embodiments and is not to be construed as limiting the scope of the subject matter described in this disclosure. Certain features from different aspects of the following description may be combined to form new aspects of the subject matter discussed below.

[0026] When identifying multiple elements or components that can be individually identified, this document uses descriptors such as “first,” “second,” “third,” etc. Unless otherwise stated or understood in the context of their use, such descriptors are not intended to assign any meaning to priority, physical order, or arrangement in the list, or chronological order, but are merely labels to separately identify multiple elements or components for ease of understanding the disclosed examples. In some examples, the descriptor “first” may be used to refer to an element in the detailed description, while different descriptors (e.g., “second” or “third”) may be used in the claims to refer to the same element. In such cases, it should be understood that the use of such descriptors is solely for ease of referring to multiple elements or components.

[0027] The terms “upstream” and “downstream” refer to the relative directions of fluid flow within a fluid path. For example, “upstream” refers to the direction from which fluid flows, while “downstream” refers to the direction towards which fluid flows. As used herein, “vertical” means perpendicular to the ground. As used herein, “horizontal” means parallel to the centerline of the turbine fan 100. As used herein, “lateral” means perpendicular to the axial vertical direction (e.g., entering and exiting). Figure 1 , 2, etc. (plane).

[0028] Various terms are used herein to describe the orientation of features. As used herein, the orientation of features, forces, and moments is described with reference to the axial, radial, and circumferential directions of the vehicle associated with the feature, force, and moment. Typically, the figures are labeled with a set of axes, including the axial axis A, the radial axis R, and the circumferential axis C. Alternatively, the figures are labeled with a set of axes, including the roll axis R, the pitch axis P, and the yaw axis Y.

[0029] "Comprising" and "including" (and all forms and tenses thereof) are used herein as open-ended terms. Therefore, whenever a claim uses "comprising" or "including" in any form (e.g., including, comprising, having, etc.) in a preamble or in any type of claim statement, it should be understood that additional elements, terms, etc., may be present without exceeding the scope of the corresponding claim or reference. As used herein, when the phrase "at least" is used as a transitional term in, for example, the preamble of a claim, it is open-ended in the same way that the terms "comprising" and "including" are open-ended. The term "and / or," when used in the form of, for example, A, B, and / or C, refers to any combination or subset of A, B, C, such as (1) A alone, (2) B alone, (3) C alone, (4) A and B, (5) A and C, (6) B and C, and (7) A and B and C. As used herein in the context of describing structures, components, items, objects, and / or things, the phrase "at least one of A and B" is intended to refer to an implementation that includes any one of (1) at least one A, (2) at least one B, and (3) at least one A and at least one B. Similarly, as used herein in the context of describing structures, components, items, objects, and / or things, the phrase "at least one of A or B" is intended to refer to an implementation that includes any one of (1) at least one A, (2) at least one B, and (3) at least one A and at least one B. As used herein in the context of describing the performance or execution of processes, instructions, actions, activities, and / or steps, the phrase "at least one of A and B" is intended to refer to an implementation that includes any one of (1) at least one A, (2) at least one B, and (3) at least one A and at least one B. Similarly, as used herein in the context of describing the performance or execution of processes, instructions, actions, activities, and / or steps, the phrase "at least one of A or B" is intended to refer to an implementation that includes any one of (1) at least one A, (2) at least one B, and (3) at least one A and at least one B.

[0030] As used herein, singular references (e.g., "a," "an," "first," "second," etc.) do not exclude plurals. As used herein, the term "a" or "an" refers to one or more of that entity. The terms "a" (or "an"), "one or more," and "at least one" are used interchangeably herein. Furthermore, although listed separately, multiple means, elements, or method actions can be implemented, for example, by a single unit or processor. Moreover, while individual features may be included in different examples or claims, these may be combined, and inclusion in different examples or claims does not imply that combination of features is impractical and / or advantageous.

[0031] Gas turbine engines include multiple rows of impeller blades, multiple rows of rotor blades, etc. One or more shrouds can be radially outwardly positioned to circumferentially surround the multiple rows of rotor blades. Although the examples disclosed herein are described with reference to rotor blades in a compressor, the examples disclosed herein can be applied to rotor blades in any section of an engine. It is generally desirable to minimize the clearance between one or more shrouds and the rotor blades to minimize leakage of air and / or combustion products. However, if the clearance is too small, there is a risk that the rotor blades may rub against the shrouds, which could lead to reduced gas turbine efficiency, blade damage, etc.

[0032] In some previous examples, if one or more rotor blades contact the shroud, a pneumatic or hydraulic system could allow the shroud to move radially outward to reduce and / or prevent friction. However, pneumatic and hydraulic systems are complex and significantly increase the cost and weight of the engine. A shroud that moves radially outward upon contact with the rotor blades and does not require a pneumatic or hydraulic system can increase clearance benefits and reduce blade damage.

[0033] Based on a shroud assembly that moves radially outward upon contact with rotor blades, the examples disclosed herein can reduce the undesirable effects caused by friction between one or more rotor blades and the shroud. For example, friction can be mitigated by segmenting the shroud of a gas turbine engine to form a shroud with variable stiffness. A shroud assembly with variable stiffness may include one or more shroud arms having one or more shroud pads.

[0034] Reference will now be made in detail to examples of this disclosure, one or more of which are illustrated in the accompanying drawings. Each example is provided to explain this disclosure and not to limit it. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made to this disclosure without departing from the scope or spirit of this disclosure. For example, a feature shown or described as part of an example may be used with another example to produce yet another example. Therefore, this disclosure is intended to cover such modifications and variations that fall within the scope of the appended claims and their equivalents.

[0035] Figure 1 This is a schematic cross-sectional view of a prior art turbofan-type gas turbine engine 100 (“turbofan 100”). Figure 1 As shown, the turbofan 100 defines a longitudinal or axial centerline axis 102 extending through it, for reference. Typically, the turbofan 100 may include a core turbine 104 or a gas turbine engine disposed downstream of the fan section 106.

[0036] The core turbine 104 typically includes a generally tubular outer casing 108 (“turbine casing 108”) that defines an annular inlet 110. The casing 108 may be formed from a single casing or multiple casings. The casing 108 surrounds, in a series flow relationship, a compressor section having a supercharger or low-pressure compressor 112 (“LP compressor 112”) and a high-pressure compressor 114 (“HP compressor 114”), a combustion section 116, a turbine section having a high-pressure turbine 118 (“HP turbine 118”) and a low-pressure turbine 120 (“LP turbine 120”), and an exhaust section 122. A high-pressure shaft or spool 124 (“HP shaft 124”) drivesably connects the HP turbine 118 and the HP compressor 114. A low-pressure shaft or spool 126 (“LP shaft 126”) drivesably connects the LP turbine 120 and the LP compressor 112. The LP shaft 126 may also be connected to a fan spool or shaft 128 (“fan shaft 128”) of the fan section 106. In some examples, the LP shaft 126 can be directly coupled to the fan shaft 128 (i.e., a direct drive configuration). In alternative configurations, the LP shaft 126 can be coupled to the fan shaft 128 via a reduction gearbox 130 (e.g., an indirect drive or gear-driven configuration).

[0037] like Figure 1 As shown, the fan drive 106 includes a plurality of fan blades 132 coupled to and extending radially outward from the fan shaft 128. An annular fan housing or nacelle 134 circumferentially surrounds at least a portion of the fan section 106 and / or the core turbine 104. The nacelle 134 is supported relative to the core turbine 104 by a plurality of circumferentially spaced outlet guide vanes 136. Furthermore, a downstream section 138 of the nacelle 134 may surround an outer portion of the core turbine 104 to define a bypass airflow passage 140 therebetween.

[0038] like Figure 1 As shown, air 142 enters the inlet portion 144 of the turbofan 100 during turbofan 100 operation. A first portion 146 of the air 142 flows into the bypass airflow passage 140, while a second portion 148 of the air 142 flows into the inlet 110 of the LP compressor 112. One or more sequential stages of the LP compressor stator blades 150 and rotor blades 152, coupled to the LP shaft 126, progressively compress the second portion 148 of the air 142 flowing through the LP compressor 112 to the HP compressor 114. Next, one or more sequential stages of the HP compressor stator blades 154 and rotor blades 156, coupled to the HP shaft 124, further compress the second portion 148 of the air 142 flowing through the HP compressor 114. This provides compressed air 158 to the combustion section 116, where the compressed air 158 is mixed with fuel and burned to provide combustion gases 160.

[0039] Combustion gas 160 flows through HP turbine 118, where one or more sequential stages of HP turbine stator blades 162 and HP turbine rotor blades 164, coupled to HP shaft 124, extract a first portion of kinetic and / or thermal energy from the combustion gas 160. This energy extraction supports the operation of HP compressor 114. Combustion gas 160 then flows through LP turbine 120, where one or more sequential stages of LP turbine stator blades 166 and LP turbine rotor blades 168, coupled to LP shaft 126, extract a second portion of thermal and / or kinetic energy from there. This energy extraction causes LP shaft 126 to rotate, thereby supporting the operation of LP compressor 112 and / or rotation of fan shaft 128. Combustion gas 160 then exits core turbine 104 through its exhaust section 122.

[0040] Along with the turbofan 100, the core turbine 104 serves a similar purpose and a similar environment is seen in land-based gas turbines and turbojet engines, where the ratio of the first portion 146 of air 142 to the second portion 148 of air 142 is less than that in turbofan engines and ductless fan engines where the fan section 106 lacks a nacelle 134. In each turbofan engine, turbojet engine, and ductless engine, a reduction gear (e.g., a reduction gearbox 130) may be included between any shaft and spool. For example, the reduction gearbox 130 may be located between the LP shaft 126 and the fan shaft 128 of the fan section 106.

[0041] Figure 2 It shows Figure 1 The example cross-sectional side view of an example stage of the HP compressor 114 of the turbine fan 100 shown. Figure 2 In this embodiment, HP compressor 114 includes two compressor stages. For example, HP compressor 114 includes a first stage 202 and a second stage 204 in a serial flow sequence. However, in the example disclosed herein, the total number of compressor stages may be more or less than two, depending on need or desire.

[0042] exist Figure 2 In the first stage 202, there are first rows 206 of circumferentially spaced compressor rotor blades 208 and second rows 210 of circumferentially spaced compressor stator blades 212. The second stage 204 also includes the first row 206 of rotor blades 208 and the second row 206 of stator blades 212. The rows 206 of rotor blades 208 and the rows 210 of stator blades 212 are spaced along... Figure 1 The HP shaft 124 is axially spaced apart (not shown). The rotor blades 208 are coupled to the HP shaft 124 and extend radially outward from the HP shaft 124 to the blade tip 214. During operation of the turbofan 100, the stator blades 212 remain stationary relative to the rotor blades 208.

[0043] Example compressor housing or casing 216 circumferentially surrounds rows 206 of rotor blades 208 and rows 210 of stator blades 212. Compressor housing 216 may be integral (e.g., a single housing for the entire HP compressor 114). Alternatively, compressor housing 216 may be segmented such that each segment of compressor housing 216 surrounds one or more of, for example, rows 206 of rotor blades 208 of first stage 202, rows 206 of rotor blades 208 of second stage 204, etc.

[0044] HP compressor 114 includes one or more shroud assemblies 218 that are coupled to compressor housing 216. Figure 2 The diagram shows only one shroud assembly 218 corresponding to the row 206 of rotor blades 208 of the second stage 204. However, additional shroud assemblies 218 may correspond to the row 206 of rotor blades 208 of additional stages (e.g., the first stage 202, etc.). The shroud assembly 218 is radially spaced from the blade tips 214 of the rotor blades 208 to form a gap between them. It is generally desirable to minimize the gap between the blade tips 214 and the shroud assembly 218, especially during cruise operation of the turbofan 100, to reduce leakage above the blade tips 214 and through the gap. If one or more of the rotor blades 208 contact the shroud assembly 218, the shroud assembly 218 can be moved radially outward relative to the compressor housing 216. Thus, the shroud assembly 218 can be positioned closer to the blade tips 214 relative to a previous shroud, thereby reducing the gap. Exemplary embodiments of the shroud assembly 218 are described below. Figure 3 -9 is used for description.

[0045] Figure 3 It shows Figure 1 The example cross-sectional side view of the HP compressor 114 of the turbine fan 100 shown. Figure 3 The example shown includes row 206 of rotor blades 208. For example, row 206 of rotor blades 208 may correspond to Figure 2 The first stage 202, the second stage 204, etc. Rotor blades 208 include blade tips 214. The HP compressor 114 includes a compressor housing 216 defining a shroud receiving cavity 302. The shroud receiving cavity 302 receives and positions a shroud assembly 218. The shroud receiving cavity 302 is generally axially aligned with and positioned radially outward from the rows 206 of the rotor blades 208. The shroud assembly 218 includes an outer wall 304, shroud arms 306, and shroud pads 308. The outer wall 304 is coupled to the compressor housing 216.

[0046] In the example disclosed herein, the shield assembly 218 is segmented in the axial direction. That is, the shield assembly 218 includes one or more shield arms 306. Figure 3In this design, the shield arm 306 has a hairpin-shaped structure (e.g., "<"). However, the shield arm 306 may additionally or alternatively have a mirror geometry along the radial axis (e.g., ">"). However, the shield arm 306 may have other geometries (e.g., vertical hairpin structure, curved beam structure, triangle, quadrilateral, hexagon, etc.). The shield arm 306 includes and / or is otherwise coupled to a shield pad 308, which extends radially outward from the shield receiving cavity 302. The shield arm 306 and the shield pad 308 can be any material suitable for the environment and compatible with the shield to achieve flexible shield behavior (e.g., the shield arm 306 compresses in the radial direction within selected tolerances, etc.). The shield arm 306 and the shield pad 308 can be the same material or different materials. In some examples, the shield arm 306 and / or the shield pad 308 are steel. However, the shield arm 306 and / or shield pad 308 may additionally or alternatively be an alloy of titanium, iron, or nickel having selected strength, fatigue, and / or other material properties. Alternatively or alternatively, the shield arm 306 and / or shield pad 308 may be a smart material (e.g., a shape memory alloy, etc.). In some examples, the shield pad 308 is coated. The shield pad coating may be any material suitable for the environment and compatible with the shield (e.g., to withstand contact from the blade tip 214, etc.). For example, the shield pad coating may be ceramic. In some examples, the shield pads 308 are coated with either a hard or soft material. In some examples, the materials used in the coating of the shield pad 308 alternate in the axial direction (e.g., alternating hard and soft coatings on the shield pad).

[0047] During engine operation, the blade tips 214 of the rotor blades 208 can contact the shroud pads 308. Upon contact, one or more shroud pads 308 move radially inward into the shroud receiving cavity 302. That is, the shroud arms 306 compress in the radial direction to enable the shroud pads 308 to move radially inward. For example, the shroud arms 306 cushion and / or absorb the impact of the blade tips 214. Therefore, the radial inward movement of the shroud pads 308 reduces the impact between the blade tips 214 and the shroud pads 308.

[0048] Figure 4 An example cross-sectional side view of an example first shield assembly 400 is shown. Figure 4 The example shown includes a compressor housing 216 coupled to a shield assembly 400. The shield assembly 400 includes an outer wall 402, a shield arm 404, and a shield pad 406. The shield assembly 400 is segmented in the axial direction. That is, the shield assembly 400 includes a first shield segment 408, a second shield segment 410, a third shield segment 412, a fourth shield segment 414, and a fifth shield segment 416. However, the shield assembly 400 may include fewer or more shield segments (e.g., four shield segments, six shield segments, etc.). The shield assembly 400 is... Figure 2 Alternative embodiments of the shield assembly 218 of type 3. For example, the outer wall 402 is segmented and includes anti-rotation tabs (described below).

[0049] Figure 4 Examples shown include a shield section 418 (sometimes referred to herein as "axial shield section 418") (e.g., shield sections 408, 410, 412, 414, 416). Shield section 418 includes an outer wall section 420 (e.g., corresponding to outer wall 402), a shield arm 422 (e.g., shield arm 404), and a shield pad 424 (e.g., shield pad 406). Shield arm 422 includes a first end 432 and a second end 434. For example, shield arm 422 is coupled to outer wall section 420 via the first end 432. Shield arm 422 is coupled to shield pad 424 via the second end 434. Outer wall section 420 includes an anti-rotation tab 426. Outer wall section 420 defines an anti-rotation cavity 428. In some examples, anti-rotation cavity 428 corresponds to the geometry of anti-rotation tab 426. Anti-rotation tab 426 and anti-rotation cavity 428 are rectangular. However, the anti-rotation tab 426 and / or anti-rotation cavity 428 can be any suitable geometry (e.g., triangular, etc.). The anti-rotation cavity 428 receives the anti-rotation tab 426 of an adjacent outer wall segment 420. For example, the anti-rotation cavity 428 of the first shield segment 408 receives the anti-rotation tab 426 of the second shield segment 410, the anti-rotation cavity 428 of the second shield segment 410 receives the anti-rotation tab 426 of the third shield segment 412, and so on. In the examples disclosed herein, the anti-rotation tab 426 prevents and / or reduces rotation of the shield assembly 400 about the pitch axis. That is, the anti-rotation tab 426 reduces rotation of shield segments 408, 410, 412, 414, 416 about the pitch axis.

[0050] exist Figure 4 In this configuration, the shroud assembly 400 is connected to the compressor housing 216 via a retaining ring 430. For example, the retaining ring 430 is connected to the fifth shroud section 416 and the compressor housing 216. Alternatively, the shroud assembly 400 may be integrally connected to the compressor housing 216. For example, the outer wall 402 may be brazed to the compressor housing 216.

[0051] Figure 5 An exemplary cross-sectional side view of an example second shield assembly 500 is shown. The second shield assembly 500 includes an outer wall 502, a shield arm 504, and a shield pad 506. Figure 5In this assembly, the shield arm 504 includes a solid shield arm 508 and an air-damped shield arm 510 (sometimes referred to herein as an "air-buffered hairpin 510"). For example, the air-damped shield arm 510 includes an air-damping hole 512. The shield assembly 500 includes five solid shield arms 508 and five air-damped shield arms 510. However, the shield assembly 500 may include fewer or more solid shield arms 508 and / or air-damped shield arms 510. In some examples, the solid shield arms 508 and air-damped shield arms 510 alternate in the axial direction. The shield pad 506 includes an air-damping hole 514. The air-damping holes 512 of the air-damped shield arms 510 and / or the air-damping holes 514 of the shield pad 506 enable an active / passive control system. That is, the air-damping holes 512, 514 allow air to buffer and suppress vibrations of the shield assembly 500. The active / passive control system will be discussed below. Figure 15 To describe in more detail.

[0052] Air damping holes 514 segment the shield pad 506 into a first shield pad segment 516, a second shield pad segment 518, a third shield pad segment 520, a fourth shield pad segment 522, a fifth shield pad segment 524, and a sixth shield pad segment 526. In some examples, shield pad segments 516, 518, 520, 522, 524, and 526 have the same axial length (e.g., the air damping holes 514 are evenly spaced along the axial axis). In some examples, shield pad segments 516, 518, 520, 522, 524, and 526 do not have the same axial length. Shield pad segments 516, 518, 520, 522, 524, and 526 are connected to one or more shield arms 504 (e.g., solid shield arms 508 and / or air damping shield arms 510).

[0053] Figure 6-8 Various embodiments of the shroud assembly are shown, in which it moves radially inward (e.g., into the shroud receiving cavity, not shown) in response to contact from one or more rotor blades (not shown). For example, Figure 6 The cross-sectional side view of the shield pad of the third shield assembly is rectangular. In contrast, Figure 7-8 The cross-sectional side view of the shield pad of the shield assembly is not rectangular.

[0054] Figure 6An example cross-sectional side view of an example third shield assembly 600 is shown. The third shield assembly 600 includes an outer wall 602 and shield arms 604. Shield arms 604 are coupled to the outer wall 602. Shield arms 604 and the outer wall 602 may be integrally coupled. Shield arms 604 include a first shield arm 606, a second shield arm 608, a third shield arm 610, a fourth shield arm 612, and a fifth shield arm 614. However, shield arms 604 may include more or fewer shield arms. The shield arms 604 of the shield assembly 600 have variable stiffness K. For example, the first shield arm 606, the third shield arm 610, and the fifth shield arm 614 have a first stiffness K1. The second shield arm 608 and the fourth shield arm 612 have a second stiffness K2. That is, the stiffness of the shield arms 604 alternates in the axial direction. In some examples, the stiffness of the guard arm 604 is not alternating (e.g., having the same stiffness, having different stiffness, etc.).

[0055] The shield assembly 600 includes a shield pad 616. The shield pad 616 includes a first shield pad 618, a second shield pad 620, a third shield pad 622, a fourth shield pad 624, a fifth shield pad 626, and a sixth shield pad 616. That is, the shield pad 616 of the shield assembly 600 is an independent shield pad. Therefore, the shield pads 616 form dividing lines. For example, the first shield pad 618 and the second shield pad 620 form a first dividing line 630, the second shield pad 620 and the third shield pad 622 form a second dividing line 632, the third shield pad 622 and the fourth shield pad 624 form a third dividing line 634, the fourth shield pad 624 and the fifth shield pad 626 form a fourth dividing line 636, and the fifth shield pad 626 and the sixth shield pad 628 form a fifth dividing line 638. The dividing lines 630, 632, 634, 636, and 638 of the shield assembly 600 are parallel to the radial axis. That is, the cross-sectional views of the shield pads 618, 620, 622, 624, 626, and 628 are rectangular.

[0056] The protective pad 616 is connected to the protective arm 604. For example, the first protective arm 606 is connected to the second protective pad 620, the second protective arm 608 is connected to the third protective pad 622, and so on. Figure 6 In the diagram, the shield arm corresponding to the first shield pad 618 is not shown. The shield pad 616 may have the same stiffness as the corresponding shield arm 604 (e.g., the first shield arm 606 and the second shield pad 620 have the same stiffness K1, the second shield arm 608 and the third shield pad 622 have the same stiffness K2, etc.). However, the shield pad 616 may have a different stiffness than the corresponding shield arm 604.

[0057] Figure 7An example cross-sectional side view of an example fourth shield assembly 700 is shown. The fourth shield assembly 700 includes an outer wall 702 and shield arms 704. Shield arms 704 are coupled to the outer wall 702. For example, shield arms 704 and outer wall 702 may be integrally coupled. Shield arms 704 include a first shield arm 706, a second shield arm 708, a third shield arm 710, a fourth shield arm 712, and a fifth shield arm 714. However, shield arms 704 may include more or fewer shield arms. The shield arms 704 of the shield assembly 700 have variable stiffness K. For example, the first shield arm 706, the third shield arm 710, and the fifth shield arm 714 have a first stiffness K1. The second shield arm 708 and the fourth shield arm 712 have a second stiffness K2. That is, the stiffness of the shield arms 704 alternates in the axial direction. In some examples, the stiffness of the guard arm 704 is not alternating (e.g., the guard arm 704 has the same stiffness, different stiffnesses, etc.).

[0058] The shield assembly 700 includes a shield pad 716. The shield pad 716 includes a first shield pad 718, a second shield pad 720, a third shield pad 722, a fourth shield pad 724, a fifth shield pad 726, and a sixth shield pad 726. That is, the shield pad 716 of the shield assembly 700 is an independent shield pad. Therefore, the shield pads 716 form dividing lines. For example, the first shield pad 718 and the second shield pad 720 form a first dividing line 730, the second shield pad 720 and the third shield pad 722 form a second dividing line 732, the third shield pad 722 and the fourth shield pad 724 form a third dividing line 734, the fourth shield pad 724 and the fifth shield pad 726 form a fourth dividing line 736, and the fifth shield pad 726 and the sixth shield pad 728 form a fifth dividing line 738. The dividing lines 730, 732, 734, 736, and 738 of the protective shield assembly 700 are not parallel to the radial axis. That is to say, with... Figure 6 Unlike the shield assembly 600, the cross-sectional views of shield pads 718, 720, 722, 724, 726, and 728 are not rectangular. Furthermore, the dividing lines 730, 732, 734, 736, and 738 are not parallel to each other. Therefore, shield pads 718, 720, 722, 724, 726, and 728 are interlocked.

[0059] The protective pad 716 is connected to the protective arm 704. For example, the first protective arm 706 is connected to the second protective pad 720, the second protective arm 708 is connected to the third protective pad 722, and so on. Figure 7In the diagram, the shield arm corresponding to the first shield pad 718 is not shown. The shield pad 716 may have the same stiffness as the corresponding shield arm 704 (e.g., the first shield arm 706 and the second shield pad 720 have the same stiffness K1, the second shield arm 708 and the third shield pad 722 have the same stiffness K2, etc.). However, the shield pad 716 may have a different stiffness than the corresponding shield arm 704.

[0060] Figure 8 An example cross-sectional side view of an example fifth shield assembly 800 is shown. The fifth shield assembly 800 includes an outer wall 802 and shield arms 804. Shield arms 804 are coupled to the outer wall 802. For example, shield arms 804 and outer wall 802 may be integrally coupled. Shield arms 804 include a first shield arm 806, a second shield arm 808, a third shield arm 810, a fourth shield arm 812, and a fifth shield arm 814. However, shield arms 804 may include more or fewer shield arms. The shield arms 804 of the shield assembly 800 have variable stiffness K. For example, the first shield arm 806, the third shield arm 810, and the fifth shield arm 814 have a first stiffness K1. The second shield arm 808 and the fourth shield arm 812 have a second stiffness K2. That is, the stiffness of the shield arms 804 alternates in the axial direction. In some examples, the stiffness of the guard arm 804 is not alternating (e.g., the guard arm 804 has the same stiffness, different stiffnesses, etc.).

[0061] The shield assembly 800 includes a shield pad 816. The shield pad 816 includes a first shield pad 818, a second shield pad 820, a third shield pad 822, a fourth shield pad 824, a fifth shield pad 826, and a sixth shield pad 828. That is, the shield pad 816 of the shield assembly 800 is an independent shield pad. Therefore, the shield pads 816 form dividing lines. For example, the first shield pad 818 and the second shield pad 820 form a first dividing line 830, the second shield pad 820 and the third shield pad 822 form a second dividing line 832, the third shield pad 822 and the fourth shield pad 824 form a third dividing line 834, the fourth shield pad 824 and the fifth shield pad 826 form a fourth dividing line 836, and the fifth shield pad 826 and the sixth shield pad 828 form a fifth dividing line 838. The dividing lines 830, 832, 834, 836, and 838 of the protective shield assembly 800 are not parallel to the radial axis. That is to say, with... Figure 6 Unlike the shield assembly 600, the cross-sectional views of shield pads 818, 820, 822, 824, 826, and 828 are not rectangular. Furthermore, compared to... Figure 7 The dividing lines 730, 732, 734, 736, and 738 are different, while the dividing lines 830, 832, 834, 836, and 838 are parallel to each other. The protective pads 818, 820, 822, 824, 826, and 828 are interlocked.

[0062] The protective pad 816 is connected to the protective arm 804. For example, the first protective arm 806 is connected to the second protective pad 820, the second protective arm 808 is connected to the third protective pad 822, and so on. Figure 8 In the example shown, the shield arm corresponding to the first shield pad 818 is not shown. The shield pad 816 may have the same stiffness as the corresponding shield arm 804 (e.g., the first shield arm 806 and the second shield pad 820 have the same stiffness K1, the second shield arm 808 and the third shield pad 822 have the same stiffness K2, etc.). However, the shield pad 816 may have a different stiffness than the corresponding shield arm 804.

[0063] Figure 9A An example cross-sectional side view of an example sixth shield assembly 900 is shown. The sixth shield assembly 900 includes an outer wall 902 and shield arms 904. Shield arms 904 are coupled to the outer wall 902. For example, shield arms 904 and the outer wall 902 may be integrally coupled. Shield arms 904 include a first shield arm 906, a second shield arm 908, a third shield arm 910, a fourth shield arm 912, and a fifth shield arm 914. However, shield arms 904 may include more or fewer shield arms. The shield arms 904 of the shield assembly 900 have variable stiffness K. For example, the first shield arm 906, the third shield arm 910, and the fifth shield arm 914 have a first stiffness K1. The second shield arm 908 and the fourth shield arm 912 have a second stiffness K2. That is, the stiffness of the shield arms 904 alternates in the axial direction. Figure 9A In this context, the first stiffness is less than the second stiffness (e.g., K1 < K2). In some examples, the first stiffness is the shell (e.g., Figure 2 The stiffness of the compressor housing (216) is 10-20%. In some examples, the second stiffness is 2-5 times greater than the first stiffness.

[0064] The shield assembly 900 includes a shield pad 916. The shield pad 916 includes a first shield pad 918, a second shield pad 920, a third shield pad 922, a fourth shield pad 924, a fifth shield pad 926, a sixth shield pad 928, and a seventh shield pad 930. That is, the shield pad 916 of the shield assembly 900 is an independent shield pad. The shield pad 916 is connected to a shield arm 904. For example, the first shield arm 906 is connected to the second shield pad 920, the second shield arm 908 is connected to the third shield pad 922, and so on. In Figure 9, the shield arms corresponding to the first shield pad 918 and the seventh shield pad 930 are not shown. The shield pad 916 may have the same stiffness as the corresponding shield arm 904 (for example, the first shield arm 906 and the second shield pad 920 have the same stiffness K1, the second shield arm 908 and the third shield pad 922 have the same stiffness K2, etc.).

[0065] The protective pads 918, 920, 922, 924, 926, 928, and 930 interlock with the stepped geometry. For example, the first protective pad 918 has a protective pad base 932 and a protective pad end 934, the second protective pad 920 has a protective pad base 936 and a protective pad end 938, the third protective pad 922 has a protective pad base 940 and a protective pad end 942, the fourth protective pad 924 has a protective pad base 944 and a protective pad end 946, the fifth protective pad 926 has a protective pad base 948 and a protective pad end 950, the sixth protective pad 928 has a protective pad base 952 and a protective pad end 954, and the seventh protective pad 930 has a protective pad base 956 and a protective pad end 958. The bases of the protective pads 932, 940, 948, and 956 have a greater axial length than the corresponding ends of the protective pads 934, 942, 950, and 958. The bases of the protective pads 936, 944, and 952 have a shorter axial length than the corresponding ends of the protective pads 938, 946, and 954.

[0066] Protective pads 918, 922, 926, and 930 are located in a first position, while protective pads 920, 924, and 928 are located in a second position. That is, the protective pad ends 934, 942, 950, and 958 of protective pads 918, 922, 926, and 930 are located in the first position 960. The protective pad ends 938, 946, and 954 of protective pads 920, 924, and 928 are located in the second position 962. The second position 962 is positioned radially inward (e.g., a lower radial position) relative to the first position 960. Therefore, the protective pad ends 938, 946, and 954 can be the first points of contact with rotor blades (not shown).

[0067] Figure 9B It shows Figure 9A Example cross-sectional side view of the sixth shield assembly 900. About Figure 9A The protective pads 918, 920, 922, 924, 926, 928, and 930 are aligned. For example, Figure 2The blade tip 214 of rotor blade 208 contacts the ends 938, 946, and 954 of the shroud pads. Upon contact, the shroud pads 920, 924, and 928 move radially outward from the second position 962 to the first position 960. For example, the shroud arms 906, 910, and 914 corresponding to the shroud pads 920, 924, and 928 are compressed along the radial axis. In some examples, the movement of the shroud pads 920, 924, and 928 is restricted by the shroud pads 918, 922, 926, and 930. That is, the shroud arms 908 and 912 and / or the shroud pads 918, 922, 926, and 930 act as deflection limiters. For example, because the guard arms 908 and 912 have higher stiffness than the guard arms 906, 910, and 914, if the rotor blades contact the guard pads 918, 922, 926, and 930, the guard pads 918, 922, 926, and 930 will not move and / or will move radially outward by a negligible amount. Therefore, the bases 932, 940, 948, and 956 of the guard pads restrict the radial movement of the guard pads 920, 924, and 928.

[0068] Figure 10 It shows Figure 2 Example front view of the shield component -9. Figure 10 This includes circumferential shield section 1000 and circumferential shield section 1002. For example, circumferential shield sections 1000 and 1002 can be made of... Figure 2 -9 shield assemblies (e.g., shield assemblies 218, 400, 500, 600, 700, 800, 900) are implemented. The circumferential shield segment 1000 is not circumferentially segmented. That is, the axial shield segment (not shown) of the circumferential shield segment 1000 is a 360-degree axial hairpin damper (e.g., a 360-degree axial segment). Instead, the circumferential shield segment 1002 is circumferentially segmented. The circumferential shield segment 1002 includes a first circumferential shield segment 1004, a second circumferential shield segment 1006, a third circumferential shield segment 1008, and a fourth circumferential shield segment 1010. However, the circumferential shield segment 1002 may include more or fewer circumferential shield segments (e.g., three circumferential shield segments, five circumferential shield segments, etc.). Circumferential shield segments 1004, 1006, 1008, and 1010 are 90-degree segments. However, the circumferential shield section 1002 may include a 30-degree circumferential shield section, a 180-degree circumferential shield section, etc. In some examples, the circumferential shield sections have the same dimensions (e.g., circumferential length). In some examples, the circumferential shield sections have different dimensions. In some examples, the circumferential shield sections 1004, 1006, 1008, and 1010 can be connected by bolts, screws, etc.

[0069] Figure 11A-12 Various embodiments of the protective pad are shown. Figure 11A-12 A bottom view of the protective pad is shown. Figure 2The shield pad of the -9 shield assembly can be made of Figure 11A-12 The protective pad shown is used for implementation. For example, Figure 2 The -9 shield pad can be circumferentially segmented parallel to the axial axis, at the same circumferential position (e.g., aligned), etc. Alternatively or concurrently, Figure 2 The -9 shield pad may include anti-rotation tabs.

[0070] Figure 11A An example bottom view of the protective pad 1100 is shown. The protective pad 1100 includes a first protective pad 1102, a second protective pad 1104, a third protective pad 1106, a fourth protective pad 1108, a fifth protective pad 1110, and a sixth protective pad 1112. The first protective pad 1102 and the second protective pad 1104 form a first dividing line 1114, the third protective pad 1106 and the fourth protective pad 1108 form a second dividing line 1116, and the fifth protective pad 1110 and the sixth protective pad 1112 form a third dividing line 1118. That is, the protective pad 1100 is circumferentially segmented. Protective pads 1102, 1104, 1106, and 1108 form a fourth dividing line 1120, while protective pads 1106, 1108, 1110, and 1112 form a fifth dividing line 1122. Dividing lines 1114, 1116, and 1118 are parallel to the axial axis. That is to say, dividing lines 1114, 1116, and 1118 are perpendicular to dividing lines 1120 and 1122.

[0071] Figure 11B An example bottom view of the protective pad 1130 is shown. The protective pad 1130 includes a first protective pad 1132, a second protective pad 1134, a third protective pad 1136, a fourth protective pad 1138, a fifth protective pad 1140, and a sixth protective pad 1142. The first protective pad 1132 and the second protective pad 1134 form a first dividing line 1144, the third protective pad 1136 and the fourth protective pad 1138 form a second dividing line 1146, and the fifth protective pad 1140 and the sixth protective pad 1142 form a third dividing line 1148. That is, the protective pad 1130 is circumferentially segmented. Protective pads 1132, 1134, 1136, and 1138 form a fourth dividing line 1150, while protective pads 1136, 1138, 1140, and 1142 form a fifth dividing line 1152. Dividing lines 1144, 1146, and 1148 are not parallel to the axial axis. That is, dividing lines 1144, 1146, and 1148 are not perpendicular to dividing lines 1150 and 1152. Figure 11B In the example, the dividing lines 1144, 1146, and 1148 are not parallel to each other. However, in some examples, the dividing lines 1144, 1146, and 1148 are parallel to each other. The dividing lines 1144, 1146, and 1148 are aligned.

[0072] Figure 11CAn example bottom view of the protective pad 1160 is shown. The protective pad 1160 includes a first protective pad 1162, a second protective pad 1164, a third protective pad 1166, a fourth protective pad 1168, a fifth protective pad 1170, and a sixth protective pad 1172. The first protective pad 1162 and the second protective pad 1164 form a first dividing line 1174, the third protective pad 1166 and the fourth protective pad 1168 form a second dividing line 1176, and the fifth protective pad 1170 and the sixth protective pad 1172 form a third dividing line 1178. That is, the protective pad 1160 is circumferentially segmented. Protective pads 1162, 1164, 1166, and 1168 form a fourth dividing line 1180, while protective pads 1166, 1168, 1170, and 1172 form a fifth dividing line 1182. Dividing lines 1174, 1176, and 1178 are not parallel to the axial axis. That is, dividing lines 1174, 1176, and 1178 are not perpendicular to dividing lines 1180 and 1182. Figure 11C In the example, the dividing lines 1174, 1176, and 1178 are not parallel to each other. However, in some examples, the dividing lines 1174, 1176, and 1178 are parallel to each other. The dividing lines 1174, 1176, and 1178 are not aligned (e.g., the dividing lines 1174, 1176, and 1178 are offset).

[0073] Figure 12 An example bottom view of a shield pad 1200 including an anti-rotation tab is shown. The shield pad 1200 includes a first shield pad 1202, a second shield pad 1204, a third shield pad 1206, and a fourth shield pad 1208. For example, shield pads 1202, 1204, 1206, and 1208 are coupled to corresponding shield arms and / or outer walls (not shown). Shield pads 1202, 1204, 1206, and 1208 include an anti-rotation tab 1210 (not marked relative to shield pads 1204, 1206, and 1208). Shield pads 1202, 1204, 1206, and 1208 define an anti-rotation cavity 1212 (not marked relative to shield pads 1202, 1204, and 1206) to receive the anti-rotation tab 1210. For example, the anti-rotation cavity 1212 of the first shield pad 1202 receives the anti-rotation tab 1210 of the second shield pad 1204, and the anti-rotation cavity 1212 of the second shield pad 1204 receives the anti-rotation tab 1210 of the third shield pad 1206, etc. The anti-rotation tab 1210 prevents and / or reduces the rotation (e.g., entry and exit) of the shield pads 1202, 1204, 1206, and 1208 about the yaw axis. Figure 12 (the plane).

[0074] Figure 13 It shows Figure 2-9 Example bottom perspective view of the shield assembly 218. For example, the shield assembly 218 includes a first shield section 1302, a second shield section 1304, and a third shield section 1306. Shield sections 1302, 1304, and 1306 are coupled to the compressor housing 216 ( Figure 2 ).exist Figure 13 In the middle, shield sections 1302, 1304, and 1306 have a thickness of 1308 (not marked relative to shield sections 1302 and 1306). The thickness 1308 of shield sections 1302, 1304, and 1306 can be 40-70 mm, corresponding to 1 × 10⁻⁶ mm / inch. 5 - 5×10 5 Radial stiffness in pounds-forces (lbf). However, in some examples, the thickness 1308 can be greater than or less than 40-70 mm. In some examples, shield sections 1302, 1304, and 1306 have the same thickness 1308. Alternatively or concurrently, shield sections 1302, 1304, and 1306 have different thicknesses 1308. For example, the first shield section 1302 and the third shield section 1306 have a thickness of 40 mm, while the second shield section 1304 has a thickness of 70 mm. Figure 13 The protective cover assembly 218 has an axial width 1310. The axial width 1310 can be 20.32-25.4 mm. However, the axial width 1310 can be greater than or less than 20.32-24.5 mm.

[0075] Figure 14A It shows Figure 2 -9 Example perspective view of shield assembly 218. For example, shield assembly 218 can be composed of shield assembly 400 ( Figure 4 ), shield assembly 500 ( Figure 5 ), shield assembly 600 ( Figure 6 ), shield assembly 700 ( Figure 7 ), shield assembly 800 ( Figure 8 ), protective cover assembly 900 (Figure 9), etc. are implemented. Figure 14A The example shown includes row 206 of rotor blades 208 and row 210 of stator blades 212. Figure 14A The shield assembly 218 includes three shield sections. However, Figure 14A The shield assembly 218 may include fewer or more shield segments.

[0076] Figure 14B It shows Figure 2 -9 shield assembly 218 example perspective view. In some examples, Figure 14B The shield assembly 218 is a continuous shield assembly (e.g., Figure 10 A cross-sectional view of the circumferential shield section 1000. In some examples, Figure 14BThe shield assembly 218 is a circumferentially segmented shield segment. For example, the shield assembly 218 may consist of circumferential shield segments 1004, 1006, 1008, 1010 ( Figure 10 ) Implementation. For example, shield assembly 218 can be a 30-degree sector with a radial load of 700 lbf. In some examples, the stiffness of shield assembly 218 is approximately 1.4 × 10⁻⁶ inch. 5 lbf.

[0077] Figure 15 It shows Figure 2 Example cross-sectional side view of HP compressor 114. Figure 15 The HP compressor 114 includes a first stage 1502, a second stage 1504, a third stage 1506, a fourth stage 1508, a fifth stage 1510, a sixth stage 1512, a seventh stage 1514, an eighth stage 1516, and a ninth stage 1518. However, Figure 15 The HP compressor 114 may include more or fewer stages. Stages 1502, 1504, 1506, 1508, 1510, 1512, 1514, 1516, and 1518 may correspond to... Figure 2 Stages 202 and 204. That is, stages 1502, 1504, 1506, 1508, 1510, 1512, 1514, 1516, and 1518 may include a first row 206 of rotor blades 208 and a second row 210 of compressor stator blades 212 (not labeled relative to stages 1504, 1506, 1508, 1510, 1512, 1514, 1516, and 1518). The HP compressor 114 includes components coupled to the compressor housing 216 (…). Figure 2 ) shield assembly 218 ( Figure 2 For example, the shield assembly 218 corresponds to the first row 206 of the rotor blades 208 of stages 1502, 1504, 1506, 1508, 1510, 1512, 1514, 1516, and 1518.

[0078] exist Figure 15 In this configuration, the shield assembly 218 enables active / passive control of the HP compressor 114. The shield assembly 218 includes an outer wall 1520, a first shield section 1522, a second shield section 1524, a third shield section 1526, a fourth shield section 1528, a fifth shield section 1530, and a sixth shield section 1532. Shield sections 1522, 1524, 1526, 1528, 1530, and 1532 include shield arms and shield pads. The outer wall 1520 forms a first air damping orifice 1534, a second air damping orifice 1536, a third air damping orifice 1538, and a fourth air damping orifice 1540. In some examples, the shield arms of shield sections 1522, 1524, 1526, 1528, 1530, and 1532 define air damping orifices (e.g., Figure 5 Air damping orifice 512). In some examples, the shield pads of shield sections 1522, 1524, 1526, 1528, 1530, and 1532 form air damping orifices (e.g., Figure 5 Air damping orifice 514).

[0079] During cold assembly, the shield assembly 218 can be assembled with a larger clearance to avoid and / or reduce friction between the shield assembly 218 and the rows 206 of the rotor blades 208 during steady-state takeoff (SSTO). During SSTO, the clearance closes and / or its size decreases, resulting in little and / or no friction. During cruise, the manifold can open to pressurize the cavity via air damping orifices 1534, 1536, 1538, and 1540. That is, in response to the increase in pressure, the shield assembly 218 deflects radially inward. Therefore, the shield assembly 218 and the rotor blades 208 operate line-to-line during cruise.

[0080] The protective assemblies 218, 400, 500, 600, 700, 800, and / or 900 can be combined, separated, rearranged, etc. For example, the outer walls of the protective assemblies 218, 500, 600, 700, 800, and 900 can be segmented and / or include anti-rotation tabs (e.g., Figure 4 The outer wall section 420). Alternatively or additionally, the shield pads of the shield assemblies 218, 400, 500, 600, 700, 800, and 900 may be located at different radial positions (e.g., Figures 9A-9B Positions 960 and 962).

[0081] Shield assemblies 218, 400, 500, 600, 700, 800, and / or 900 can prevent and / or reduce shroud and / or airfoil degradation during normal engine operation. At least shield arms 306, 404, 504, 604, 704, 804, and 904 can be used to implement devices for reducing blade damage. For example, in... Figure 6In this configuration, the first shroud arm 606 may implement a first device for reducing blade damage, the second shroud arm 608 may implement a second device for reducing blade damage, the third shroud arm 610 may implement a third device for reducing blade damage, and so on. The reduction / prevention of shroud and / or airfoil degradation increases the reliability and durability of the rotor blades 208. The improved reliability / durability of the rotor blades 208 reduces the maintenance / repair costs of the turbofan 100. Additionally or alternatively, due to the reduced clearance, shroud assemblies 218, 400, 500, 600, 700, 800, and / or 900 may improve the specific fuel consumption rate (SFC).

[0082] During operation, the shroud assemblies of the HP compressor 114 (e.g., shroud assembly 218, shroud assembly 400, shroud assembly 500, shroud assembly 600, shroud assembly 700, shroud assembly 800, and / or shroud assembly 900, etc.) move radially outward when in contact with one or more rotor blades 208. This radial movement prevents corrosion of the shroud and / or rotor blades 208. In other words, the examples disclosed herein improve the reliability / durability of the gas turbine engine by reducing friction between the shroud and the rotor blades.

[0083] The following requirements are incorporated herein by reference, wherein each requirement exists independently as a separate embodiment of this disclosure.

[0084] Further aspects of this disclosure are provided by the subject matter of the following clauses:

[0085] Example 1 is a shield assembly for a gas turbine engine, the shield assembly comprising: a first shield arm having a first end and a second end, the first end being connected to an outer wall and the second end being connected to a first shield pad; a second shield arm having a first end and a second end, the first end being connected to an outer wall and the second end being connected to a second shield pad, at least one of the first shield pad or the second shield pad moving radially outward toward the outer wall in response to rotor blades contacting at least one of the first shield pad or the second shield pad.

[0086] Example 2 is any of the shield assembly described in the preceding clauses, wherein the first shield arm and the second shield arm have a hairpin-shaped structure.

[0087] Example 3 is any of the shielding components described in the preceding clauses, wherein the first shielding pad and the second shielding pad have air damping holes.

[0088] Example 4 is any of the shielding components described in the preceding clauses, wherein the first shielding arm has an air damping orifice.

[0089] Example 5 is any of the shielding components described in the preceding clauses, wherein the outer wall has air damping holes.

[0090] Example 6 is any of the shielding components described in the preceding clauses, wherein the first shielding arm has a first stiffness and the second shielding arm has a second stiffness.

[0091] Example 7 is any of the shielding components described in the preceding clauses, wherein a first stiffness is less than a second stiffness, a first shielding pad is located in a first position and a second shielding pad is located in a second position.

[0092] Example 8 is any of the shielding components described in the preceding clauses, wherein the first position is located in a radial position lower than the second position.

[0093] Example 9 is any of the shielding assemblies described in the preceding clauses, wherein the first shield pad moves radially outward to a second position in response to the rotor blades contacting the first shield pad.

[0094] Example 10 is any of the shielding components described in the preceding clauses, wherein at least one of the first shielding pad or the second shielding pad is coated.

[0095] Example 11 is any of the shielding components described in the preceding clauses, wherein the first shielding pad and the second shielding pad include anti-rotation tabs.

[0096] Example 12 is any of the shielding components described in the preceding clauses, wherein the outer wall includes a first outer wall segment and a second outer wall segment, a first end of a first arm is connected to the first outer wall segment, and a first end of a second arm is connected to the second outer wall segment.

[0097] Example 13 is any of the shielding components described in the preceding clauses, wherein the first outer wall segment and the second outer wall segment include anti-rotation tabs and anti-rotation cavities.

[0098] Example 14 is any of the shielding assemblies described in the preceding clauses, wherein the anti-rotation cavity of the first outer wall segment receives the anti-rotation tab of the second outer wall segment.

[0099] Example 15 is any of the shielding assemblies described in the preceding clauses, wherein the first shielding arm and the second shielding arm are 360-degree axial segments.

[0100] Example 16 is any of the shielding components described in the preceding clauses, wherein the first shielding arm and the second shielding arm are circumferentially segmented.

[0101] Example 17 is any of the shielding assemblies described in the preceding clauses, wherein a first shield pad and a second shield pad form a dividing line parallel to the radial axis.

[0102] Example 18 is any of the shielding assemblies described in the preceding clauses, wherein the first shielding pad and the second shielding pad form a dividing line that is not parallel to the radial axis.

[0103] Example 19 is any of the shielding components described in the preceding clauses, wherein the first shielding pad includes a shielding pad base and a shielding pad end, and a second end of the first arm is attached to the shielding pad base.

[0104] Example 20 is any of the shielding components described in the preceding clauses, wherein the base of the shielding pad has a smaller axial length than the end of the shielding pad of the first shielding pad.

[0105] Example 21 is any of the shielding components described in the preceding clauses, wherein the second shielding pad includes a shielding pad base and a shielding pad end, and a second end of the second arm is connected to the shielding pad base.

[0106] Example 22 is any of the shielding components described in the preceding clauses, wherein the base of the shielding pad has a greater axial length than the end of the shielding pad of the second shielding pad.

[0107] Example 23 is any of the shield components described in the preceding clauses, wherein the first shield pad includes a first shield pad segment and a second shield pad segment.

[0108] Example 24 is any of the shield assemblies described in the preceding clauses, wherein a first shield pad segment and a second shield pad segment form a dividing line parallel to the axial centerline of the gas turbine engine.

[0109] Example 25 is any of the shield components described in the preceding clauses, wherein the dividing line is a first dividing line, and the second shield pad includes a third shield pad segment and a fourth shield pad segment, the third shield pad segment and the fourth shield pad segment forming the second dividing line.

[0110] Example 26 is any of the shielding components described in the preceding clauses, wherein the second dividing line is not parallel to the axial centerline of the gas turbine engine.

[0111] Example 27 is any of the shielding components described in the preceding clauses, wherein the first dividing line and the second dividing line are aligned.

[0112] Example 28 is any of the shielding components described in the preceding clauses, wherein the first dividing line and the second dividing line are offset.

[0113] Example 29 is a gas turbine engine comprising: a compressor including a compressor housing and at least one compressor blade; a combustion section; a turbine including a turbine housing and at least one turbine blade; a shaft rotatably connecting the compressor and the turbine; and a shroud assembly for at least one of the compressor or the turbine, the shroud assembly comprising: a first shroud arm having a first end and a second end, the first end being coupled to an outer wall and the second end being coupled to a first shroud pad; and a second shroud arm having a first end and a second end, the first end being coupled to an outer wall and the second end being coupled to a second shroud pad, at least one of the first shroud pad or the second shroud pad moving radially outward toward the outer wall in response to contact of a rotor blade with at least one of the first shroud pad or the second shroud pad.

[0114] Example 30 is any of the gas turbine engines described in the preceding clauses, wherein the first shield pad is located in a first position and the second shield pad is located in a second position, the first position being a radial position lower than the second position.

[0115] Example 31 is any of the gas turbine engines described in the preceding clauses, wherein the first shroud moves radially outward to a second position in response to the rotor blades contacting the first shroud.

[0116] Example 32 is a protective cover device, comprising: a first means for reducing blade damage, having a first end and a second end, the first end being connected to an outer wall of a protective cover assembly and the second end being connected to a first protective cover pad; and a second means for reducing blade damage, having a first end and a second end, the first end being connected to an outer wall and the second end being connected to a second protective cover pad, at least one of the first protective cover pad or the second protective cover pad moving radially outward toward the outer wall in response to a rotor blade contacting at least one of the first protective cover pad or the second protective cover pad.

[0117] Although certain example methods, apparatuses, and articles of manufacture have been disclosed herein, the scope of this patent is not limited thereto. Rather, this patent covers all methods, apparatuses, and articles of manufacture that fall fully within the scope of the claims of this patent.

[0118] The following claims are incorporated herein by reference, wherein each claim exists independently as a separate embodiment of this disclosure.

Claims

1. A shield assembly for a gas turbine engine, characterized in that, The protective shield assembly includes: outer wall; A first protective arm has a first end and a second end. The first end is connected to the outer wall, and the second end is connected to a first protective pad. A first angular bend is provided between the first end and the second end of the first protective arm. The first protective arm further includes a first straight portion located between the first end and the first angular bend, and a second straight portion located between the first angular bend and the second end. The first angular bend is formed at the intersection of the first straight portion and the second straight portion. The second protective arm has a third end and a fourth end, the third end being connected to the outer wall and the fourth end being connected to the first protective pad. A second angular bend is provided between the third end and the fourth end of the second protective arm. The second protective arm further includes a third straight portion located between the third end and the second angular bend, and a fourth straight portion located between the second angular bend and the fourth end. The second angular bend is formed at the intersection of the third straight portion and the fourth straight portion. The protective assembly includes at least one air damping hole, which is located on at least one of the outer wall or the second protective arm.

2. The protective cover assembly according to claim 1, characterized in that, in, When the at least one air damping hole is located on the second shield arm, the third straight portion is divided into a fifth straight portion and a sixth straight portion, and the division of the third straight portion forms the at least one air damping hole.

3. The protective cover assembly according to claim 1, characterized in that, in, When the at least one air damping hole is located on the second shield arm, one of the first shield arms and one of the second shield arms are alternately arranged in the axial direction.

4. The protective cover assembly according to claim 1, characterized in that, When the at least one air damping orifice is located on the second shield arm, it further includes a second shield pad, the first shield pad defining a first vertical plane, the second shield pad defining a second vertical plane, the first vertical plane being parallel to the second vertical plane.

5. The protective cover assembly according to claim 4, characterized in that, in, At least one second air damping hole is provided between the first protective pad and the second protective pad.

6. The protective cover assembly according to claim 4, characterized in that, in, The first protective pad and the second protective pad have the same axial length.

7. The protective cover assembly according to claim 4, characterized in that, in, The first protective pad and the second protective pad have different axial lengths.

8. The protective cover assembly according to claim 1, characterized in that, in, When the at least one air damping orifice is located on the outer wall, the outer wall is divided into a first part and a second part, and the division of the outer wall forms the at least one air damping orifice.

9. The protective cover assembly according to claim 8, characterized in that, in, When the at least one air damping orifice is located on the outer wall, the first end of the first shield arm is connected to the first portion of the outer wall, and the third end is connected to the second portion of the outer wall.

10. The protective cover assembly according to claim 8, characterized in that, in, When the at least one air damping hole is located on the outer wall, the first shield arm is attached to the first shield pad, and the second shield arm is attached to the second shield pad.

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