Patent ID: 12246845

The figures are not to scale. Instead, the thickness of the layers or regions may be enlarged in the drawings. In general, the same reference numbers will be used throughout the drawing(s) and accompanying written description to refer to the same or like parts. As used in this patent, stating that any part (e.g., a layer, film, area, region, or plate) is in any way on (e.g., positioned on, located on, disposed on, or formed on, etc.) another part, indicates that the referenced part is either in contact with the other part, or that the referenced part is above the other part with one or more intermediate part(s) located therebetween. Connection references (e.g., attached, coupled, connected, joined, detached, decoupled, disconnected, separated, etc.) are to be construed broadly and may include intermediate members between a collection of elements and relative movement between elements unless otherwise indicated. As used herein, the term “decouplable” refers to the capability of two parts to be attached, connected, and/or otherwise joined and then be detached, disconnected, and/or otherwise non-destructively separated from each other (e.g., by removing one or more fasteners, removing a connecting part, etc.). As such, connection/disconnection references do not necessarily infer that two elements are directly connected and in fixed relation to each other. Stating that any part is in “contact” with another part means that there is no intermediate part between the two parts.

Descriptors “first,” “second,” “third,” etc. are used herein when identifying multiple elements or components which may be referred to separately. Unless otherwise specified or understood based on their context of use, such descriptors are not intended to impute any meaning of priority, physical order or arrangement in a list, or ordering in time but are merely used as labels for referring to multiple elements or components separately 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 the same element may be referred to in a claim with a different descriptor such as “second” or “third.” In such instances, it should be understood that such descriptors are used merely for ease of referencing multiple elements or components.

DETAILED DESCRIPTION

Compressor blade tip clearances in gas turbine engines are reduced by operational distortions caused by internal forces of the gas turbine engines. Particularly, thrust and aero inlet loads can create internal bending moments in the gas turbine engine, which can cause the gas turbine engine to bend between the mounting linkages of the gas turbine engines. Certain examples disclosed herein provide a mounting system to react some or all of the bending moments between thrust linkages of the engine, which reduces the operational distortions caused by bending moments transferred by carcass of the gas turbine engine. Other examples disclosed herein provide a gas turbine with a cantilevered core, which improves access to the engine core during maintenance and disassembly and reduces stress in the engine core.

The terms “upstream” and “downstream” refer to the relative direction with respect to fluid flow in a fluid pathway. For example, “upstream” refers to the direction from which the fluid flows, and “downstream” refers to the direction to which the fluid flows.

Various terms are used herein to describe the orientation of features. As used herein, the orientation of features, forces and moments are described with reference to the yaw axis, pitch axis, and roll axis of the vehicle associated with the features, forces and moments. In general, the attached figures are annotated with reference to the axial direction, radial direction, and circumferential direction of the gas turbine associated with the features, forces and moments. In general, the attached figures are annotated with a set of axes including the roll axis R, the pitch axis P, and the yaw axis Y. As used herein, the terms “longitudinal,” and “axial” are used interchangeably to refer to directions parallel to the roll axis. As used herein, the term “lateral” is used to refer to directions parallel to the pitch axis. As used herein, the term “vertical” and “normal” are used interchangeably to refer to directions parallel to the yaw axis.

In some examples used herein, the term “substantially” is used to describe a relationship between two parts that is within three degrees of the stated relationship (e.g., a substantially colinear relationship is within three degrees of being linear, a substantially perpendicular relationship is within three degrees of being perpendicular, a substantially parallel relationship is within three degrees of being parallel, etc.). As used herein, the term “linkage” refers to a connection between two parts that restrain the relative motion of the two parts (e.g., restrain at least one degree of freedom of the parts, etc.). “Including” and “comprising” (and all forms and tenses thereof) are used herein to be open ended terms. Thus, whenever a claim employs any form of “include” or “comprise” (e.g., comprises, includes, comprising, including, having, etc.) as a preamble or within a claim recitation of any kind, it is to be understood that additional elements, terms, etc. may be present without falling outside the scope of the corresponding claim or recitation. As used herein, when the phrase “at least” is used as the transition term in, for example, a preamble of a claim, it is open-ended in the same manner as the term “comprising” and “including” are open ended. The term “and/or” when used, for example, in a form such as 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 with B, (5) A with C, (6) B with C, and (7) A with B and with 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 implementations including any 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 implementations including any 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 implementations including any 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 implementations including any 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, singular references (e.g., “a”, “an”, “first”, “second”, etc.) do not exclude a plurality. The term “a” or “an” entity, as used herein, refers to one or more of that entity. The terms “a” (or “an”), “one or more”, and “at least one” can be used interchangeably herein. Furthermore, although individually listed, a plurality of means, elements or method actions may be implemented by, e.g., a single unit or processor. Additionally, although individual features may be included in different examples or claims, these may possibly be combined, and the inclusion in different examples or claims does not imply that a combination of features is not feasible and/or advantageous.

Gas turbine engines can be mounted to the wings of the aircrafts (e.g., under-wing mounting) via a pylon. These pylons transfer the loads associated with the operation of gas turbine engines (e.g., thrust loads, aero-inlet loads, weight, etc.) to the wing of the aircraft. In some examples, the gas turbine engine is mounted to the pylon via a forward mount and an aft mount for the engine. In some prior-art examples, the forward mount couples the fan casing of the gas turbine engine to the pylon and the aft mount couples the core casing of the gas turbine engine to the gas turbine engine.

Blade tip clearances at several locations throughout the engine are often defined based on the sum of axisymmetric closures and the local circumferential clearance distortions during a take-off (TO) rotation maneuver. That is, in some examples, the minimum blade tip clearances in the compressor (e.g., closest clearances, etc.) can occur during TO engine operation. In some examples, the minimum blade tip clearance at which the compressor can operate during take-off is based on clearance reduction caused in part by engine vibrations and distortion (e.g., strain, etc.) caused by operation of the engine. Operational distortion in an engine can be caused by internal forces and/or moments in the engine caused by thrust and aero inlet loads, etc. The operational loads can cause the engine body to bend and/or otherwise distort between the forward and aft mount attachment point of engine to the aircraft, for example. Designing an engine to compensate for these distortions (e.g., by increasing cold or cruise clearances) correspondingly reduces engine operating efficiency (e.g., specific fuel consumption, etc.). In some prior-art engine configurations, the generated bending moments (e.g., moments about the yaw and pitch axis, etc.) are reacted through the engine carcass (e.g., the fan and core sections of the engine, etc.). The reaction of the bending moments through the engine carcass can cause deterioration (e.g., deformation, distortion) of the engine, which in turn affect blade tip clearances. As such, a mounting system that causes the pitch and/or yaw moments to be reacted outside of the engine carcass (e.g., by thrust linkages, etc.) reduces the necessary cold clearances, which improves engine efficiency (e.g., specific fuel consumption, etc.), improves engine operability, and reduces engine deformation (e.g., deterioration, distortion, etc.), for example.

Examples disclosed herein mitigate these deformations using engine mounting configurations which reduce and/or eliminate bending moments transferred through the engine carcass. Some examples disclosed herein include a gas turbine engine with a cantilever mounting configuration. In some such examples, the aft and forward mounts of the gas turbine engine are located on forward sections of the engine casing, which prevents downstream sections of the engine from reacting bending moments between the aft and forward section and enables the on-wing removal of these downstream sections. Some examples disclosed herein include multiple offset thrust linkages, which prevents pitch and/or yaw bending moments from being reacted between the forward and aft sections. Some examples disclosed herein include mounts with pylon internal mount fastening features, which improves packaging space and reduces ground clearance parameters.

Referring now to the drawings, wherein identical numerals indicate the same elements throughout the figures,FIG.1is a schematic cross-sectional view of a prior-art turbofan-type gas turbine engine100(“turbofan100”). As shown inFIG.1, the turbofan100defines a longitudinal or axial centerline axis102extending therethrough for reference. In general, the turbofan100includes a core section104disposed downstream from a fan section106.

The core section104generally includes a substantially tubular outer casing108that defines an annular inlet110. The outer casing108can be formed from a single casing or multiple casings. The outer casing108encloses, in serial flow relationship, a compressor section having a booster or low pressure compressor112(“LP compressor112”) and a high pressure compressor114(“HP compressor114”), a combustion section116, a turbine section having a high pressure turbine118(“HP turbine118”) and a low pressure turbine120(“LP turbine120”), and an exhaust section122. A high pressure shaft or spool124(“HP shaft124”) drivingly couples the HP turbine118and the HP compressor114. A low pressure shaft or spool126(“LP shaft126”) drivingly couples the LP turbine120and the LP compressor112. The LP shaft126may also couple to a fan spool or shaft128of the fan section106. In some examples, the LP shaft126may couple directly to the fan shaft128(i.e., a direct-drive configuration).

As shown inFIG.1, the fan section106includes a plurality of fan blades130coupled to and extending radially outwardly from the fan shaft128. An annular fan casing132, (e.g., a nacelle, etc.) circumferentially encloses the fan section106and/or at least a portion of the core section104. The annular fan casing132is supported relative to the core section104by a plurality of circumferentially-spaced apart outlet guide vanes134. Furthermore, a downstream section136of the annular fan casing132can enclose an outer portion of the core section104to define a bypass airflow passage138therebetween.

As illustrated inFIG.1, air140enters an inlet portion142of the turbofan100during operation thereof. A first portion144of the air140flows into the bypass flow passage138, while a second portion146of the air140flows into the inlet110of the LP compressor112. One or more sequential stages of LP compressor stator vanes148and LP compressor rotor blades150coupled to the LP shaft126progressively compress the second portion146of the air140flowing through the LP compressor112en route to the HP compressor114. Next, one or more sequential stages of HP compressor stator vanes152and HP compressor rotor blades154coupled to the HP shaft124further compress the second portion146of the air140flowing through the HP compressor114. This provides compressed air156to the combustion section116where it mixes with fuel and burns to provide combustion gases158.

The combustion gases158flow through the HP turbine118in which one or more sequential stages of HP turbine stator vanes160and HP turbine rotor blades162coupled to the HP shaft124extract a first portion of kinetic and/or thermal energy from the combustion gases158This energy extraction supports operation of the HP compressor114. The combustion gases158then flow through the LP turbine120where one or more sequential stages of LP turbine stator vanes164and LP turbine rotor blades166coupled to the LP shaft126extract a second portion of thermal and/or kinetic energy therefrom. This energy extraction causes the LP shaft126to rotate, thereby supporting operation of the LP compressor112and/or rotation of the fan shaft128. The combustion gases158then exit the core section104through the exhaust section122thereof.

The prior-art mounting configurations ofFIGS.2-3are described with reference to the engine components described in conjunction withFIG.1. However, the prior-art mounting configurations ofFIGS.2-3are illustrated on different gas turbine engines than the one illustrated inFIG.1. The repeated part numbers are for descriptive purposes only.

FIG.2illustrates a cross sectional view of the prior-art gas turbine engine100ofFIG.1via a first prior-art mounting configuration200. The first prior-art mounting configuration200includes a pylon202, which is coupled to the gas turbine engine100via a forward mount204, an aft mount206, and a thrust linkage208. A portion of the weight and operational stresses of the engine are reacted between the mounts204,206, which defines engine off, no-aerodynamic force, load paths210A,210B, respectively. The thrust linkage208reacts the axial stress of the weight and operational stresses. The pylon202is coupled to a plane wing212. The load paths210A,210B illustrate that the operational stress of the gas turbine engine100is carried through the outer guide vane(s)134and the flow path components of the engine (e.g., the LP compressor112, the HP compressor114, the combustor,116, the HP turbine118, the LP turbine120, etc.). In other examples, if the gas turbine engine100is operating or the undergoing aerodynamic loading, additional load will be transferred via the thrust linkage208. As such, the flow path components of the gas turbine engine100are distorted by the bending moments reacted between the mounts204,206, which can affect blade tip clearance and engine performance.

FIG.3illustrates a cross sectional view of the prior-art gas turbine engine100ofFIG.1via a second prior-art mounting configuration300. The second prior-art mounting configuration300includes a pylon202, which is coupled to the gas turbine engine100via a forward mount304and an aft mount306. The weight and operational stresses of the engine are reacted between the mounts304,306, which defines load paths308A,308B. The pylon202is coupled to the plane wing212. InFIG.3, the mounts304,306are coupled to the annular fan casing132of the gas turbine engine100. The load paths308A,308B illustrates the operational stress of the engine100is carried through the annular fan casing132and the outer guide vane(s)134. In the prior-art example ofFIG.2, the bending moments between the mounts304,306are reacted through the annular fan casing132and not the flow components112,114,116,118,120. As such, the distortions and/or other deterioration caused by the bending moments are reduced and/or mitigated. However, in some examples, the annular fan casing132must be removed in order to inspect, clean, or maintain the gas turbine engine100, which can greatly increase maintenance and inspection times.

The following examples refer to gas turbine engines and mounting configurations that are similar to those described with reference toFIGS.1-3, except that the engine and mounting system include features which reduce and/or eliminate bending moments transferred through the engine carcass. When the same element number is used in connection withFIGS.4A-13Bas was used inFIGS.1-3, it has the same meaning unless indicated otherwise.

FIG.4Aillustrates a gas turbine engine400with a cantilevered core section401in which the teachings of this disclosure can be implemented. In the illustrated example ofFIG.4A, the gas turbine engine400has an example mount configuration405. The example mount configuration405includes a pylon402that couples the gas turbine engine400to the wing212. The gas turbine engine400is coupled to the pylon402via a front mount404and an aft mount406and one or more thrust linkage(s)408In some examples, the thrust linkage(s)408are described as thrust linkage(s)408. The forces and moments generated by the weight and operation of the gas turbine engine400are reacted between the mounts404,406and thrust linkage(s)408.

InFIG.4A, the weight of the gas turbine engine400acts at a center of gravity410, which is between the mounts404,406. The mounts404,406are coupled to a front frame412and an intermediate compressor frame414, respectively. An example implementation of the front mount404is described inFIG.5A. An example implementation of the aft mount is described in conjunction withFIGS.5A-6. The example intermediate compressor frame414is additionally coupled to the pylon402by example thrust linkage(s)408. The mounts404,406and thrust linkage(s)408fully constrain the movement of the gas turbine engine400. That is, each of the six degrees of freedom of the gas turbine engine400are reacted via the mounts404,406and thrust linkage(s)408. InFIG.4, both the forward mount404and the aft mount406react vertical and lateral loads associated with gas turbine engine400, which defines an engine off, no-aerodynamic force load paths415A,415B. The load paths415A,415B flows between the mounts404,406, which minimizes the distortive effect on the flow path components of the gas turbine engine400. In other examples, if the gas turbine engine100is operating or the undergoing aerodynamic loading, additional load will be transferred via the thrust linkage408. As such, the yaw and pitch moments of the gas turbine (e.g., generated during operation of the gas turbine engine, etc.) are reacted by and between the mounts404,406via an imbalance of vertical and lateral loads at each of the mounts404,406. As such, the distortions associated with these bending moments are limited to the engine components between the mount404,406(e.g., the LP compressor112and HP compressor114, etc.). A simplified illustration showing the constraint of the degrees of freedom of the gas turbine engine400is described below in conjunction withFIG.4B. The example outer guide vane(s)411are generally configured to guide air through bypass of the gas turbine engine400. InFIG.4A, the placement of the outer guide vanes411are not hindered by the mounting configuration405(e.g., the placement of the thrust linkage(s)408, the front mount404, or the example aft mount406does not inhibit the packaging of the outer guide vane(s)411, etc.). The example outer guide vane(s)411can be positioned vertically, as shown inFIG.4A. Example implementations of the outer guide vane(s)411is further described below in conjunction withFIGS.7A-Band8A-B.

FIG.4Bis a perspective view of the gas turbine engine400ofFIG.4Athat illustrates how the mounting configuration405constrains each of the degrees of freedom of the gas turbine engine400. The mounting configuration405includes the front mount404, the aft mount406and the thrust linkage(s)408. InFIG.4B, the thrust linkage(s)408include a first thrust linkage413aand a second thrust linkage413b, which are coupled to the pylon402via a yoke416. While the thrust linkage(s)408are depicted as the first thrust linkage413aand the second thrust linkage413bin the example ofFIG.4B, the thrust linkages413a,413bcan be implemented as a single thrust linkage or three thrust linkages, etc.

InFIG.4B, both the front mount404and aft mount406are configured to constrain vertical and lateral forces during engine operation. Imbalances in the vertical and lateral forces additionally cause the front mount404and aft mount406, collectively, to react yaw and pitch moments associated with the gas turbine engine400. Additionally, inFIG.4B, the aft mount406is configured to restrain roll moments associated with the gas turbine engine400. The thrust linkage(s)408(e.g., first thrust linkage413aand second thrust linkage413b) constrain the axial forces associated with the gas turbine engine400. As such, in combination, the forward mount404, the aft mount406and thrust linkage(s)408constrain the six degrees of freedom of the gas turbine engine (e.g., vertical translation, lateral translation, axial translation, rotation about the yaw axis, rotation about the pitch axis, and rotation about the roll axis). The mounting configuration405of the forward mount404, the aft mount406and thrust linkage(s)408cause the gas turbine engine400to be statically determinate. Other mounting configurations implemented in accordance with the teachings of this disclosure can be statically indeterminate.

The first thrust linkage413aand the second thrust linkage413bare joined via an example yoke416. InFIG.4B, the yoke416is a whiffletree linkage. The yoke416distributes axial loads evenly between the thrust linkage(s)408. Accordingly, the yoke416prevents imbalances in the axial load on the thrust linkage(s)408which prevents the thrust linkage(s)408from constraining a bending moment therebetween. Examples including multiple thrust linkages constraining bending moments are described below.

FIG.5Ais a perspective view of an example implementation501of the mount configuration405and the pylon402ofFIGS.4A-Bincluding a detailed view of the mounts404,406and the thrust linkage(s)408ofFIGS.4A-B. InFIG.5A, the forward mount404is implemented by a trunnion502, and the aft mount406is implemented by a yoke506.

The trunnion502includes a linkage504. The trunnion502and linkage504constrain two degrees of freedom of the engine, namely, lateral and vertical translation. In other examples, the trunnion502can include additional features which can constrain additional degrees of freedom. For example, the trunnion502can include any additional linkage to constrain rotation along the roll axis. InFIG.5A, the trunnion502acts as a ball joint, which implements the linkage504as a pivot linkage. In the example ofFIG.5A, an axle505is attached (e.g., fixed, mounted, fastened) to the example trunnion502and ball joint507is attached (e.g., fixed, mounted, fastened) to the example pylon402. The example trunnion502(e.g., front mount404ofFIG.4A) supports the weight of the front frame of the engine (not shown in this view).

The yoke506includes a yoke body508, a first linkage510a, and a second linkage510b. InFIG.5A, the first linkage510aincludes a two pronged linkage and the second linkage510bincludes a three prong linkage. The second linkage510bof the yoke506prevents rotation about the roll axis. In the illustrated example ofFIG.5A, the yoke506is an external feature. In other examples, the yoke506can be integrated into the pylon402. An example implementation of an aft mount406is discussed below in conjunction withFIG.6.

FIG.5Bis a perspective view of another example implementation511of the mount configuration405and the pylon402ofFIGS.4A-B. InFIG.5B, the forward mount404is implemented by a forward yoke system512, the aft mount406is implemented by an aft link516. The implementation511occupies less space (e.g., less bulky) in the area of the core engine than the implementation501thanFIG.5A, but reacts more load at the forward end of the pylon (e.g., at the yoke system512, etc.) The forward yoke system512includes a first linkage514a, and a second linkage514b. The forward yoke system constrains three degrees of freedom, namely, lateral translation, vertical translation, and rotation along the roll axis. InFIG.5A, the first linkage514aof the forward yoke system512includes a single rod attached (e.g., fixed, mounted, fastened, etc.). InFIG.5B, the second linkage514bincludes a rod with three links.

InFIG.5B, the aft link516constrains vertical translation. Imbalances in the vertical forces additionally cause the yoke system512and aft link516, collectively, react pitch moments and thusly constrain an additional degree of freedom, namely, rotation about the pitch axis. InFIG.5B, the aft link516is implemented by a vertical rod.

InFIG.5B, the implementation511includes thrust linkage(s)408to constrain translation along the roll axis. In some examples, the thrust linkage(s)408are joined by the yoke416(e.g., a whiffletree connection, etc.), which evenly distributes load between the linkages413a,413b. In such examples, the yoke system512and/or aft link516can include additional features that allow rotation about the yaw axis to be constrained. In other examples, the yoke416can be absent. In such examples, imbalances in thrust load between the linkages413a,413benable the thrust linkage(s)408to constrain rotation about the yaw axis. An example of this configuration is further described below in conjunction withFIG.12.

FIG.6illustrates an example mounting configuration600that includes an aft mount602with integrated fasteners604a,604b. InFIG.6, the aft mount602includes a first boss606aand a second boss606b, which receive the first integrated fastener604a, and the second integrated fastener604brespectively. InFIG.6, the integrated fasteners are link lugs. In other examples, the integrated fasteners604a,604bcan be any other suitable type of fastener.

The bosses606a,606bcan be coupled to the pylon608via any suitable means (e.g., a weld, one or more fasteners, etc.). The stiffness of the aft mount602can be changed by modifying the parameters (e.g., the material, the thickness, the geometry, etc.) of the body of the pylon604and/or the bosses606a,606b. InFIG.6, the first boss606aand first integrated fastener604aform a clevis, which retains the first integrated fastener604ain the boss606a. Similarly, the second boss606band the second integrated fastener604bform a clevis, which retains the second integrated fastener604bin the second boss606b.

InFIG.6, the integrated fasteners604a,604band bosses606a,606breplace the yoke506ofFIG.5A. That is, the aft mount602constrains 3 degrees of freedom of a coupled gas turbine engine, namely lateral translation, vertical translation, and rotation about the roll axis. While the integrated fasteners604a,604bare described with reference to the aft mount602, in other examples, the fasteners associated with the front mount and/or thrust linkages of the engine may similarly be integrated into the pylon.

The mounting configuration600including integrated fasteners604a,604beliminates the need for an aft mount yoke (e.g., the yoke506ofFIG.5A, etc.), which reduces engine weight. Additionally, integration of the fasteners reduces the vertical height of mounting configuration600, which improves ground clearance and allows for larger engine diameters without the need for ovalization of the engine.

FIG.7Ais a front view of a first configuration700of a first outer guide vane,702a, a second outer guide vane702b, and a third outer guide vane702crelative to a pylon704.FIG.7Bis a top view of the first configuration700of the outer guide vanes702a,702b,702c. In the configuration700ofFIGS.7A-B, the second outer guide vane702bis positioned vertically (e.g., along the yaw axis, perpendicular to the ground when an engine including the second outer guide vane702bis assembled, etc.). The first outer guide vane702aand the third outer guide vane702care radially displaced from the second outer guide vane702bsuch that each guide vane of the first configuration700(not illustrated) is evenly spaced from the second outer guide vane702b. In the illustrated examples ofFIGS.7A and7B, the front mounts (e.g., the front mount404) of a mounting configuration (e.g., the configuration405ofFIGS.4A and4B, etc.) are to surround the second outer guide vane702bwhen the gas turbine engine400is assembled on wing.

FIG.8Ais a front view of a second configuration800of a first outer guide vane802a, a second outer guide vane802b, a third outer guide vane802c, and a fourth outer guide vane802drelative to the pylon704.FIG.8Bis a top view of the second configuration800of the outer guide vanes802a,802b,802c,802d. In the configuration800ofFIGS.8A-B, the second outer guide vane802band the third outer guide vane802care evenly displaced from the yaw-axis such that the area extending from an engine centerline803along the yaw axis is available to package the components of a mount configurations. That is, unlike the first configuration700ofFIGS.7A and7B, the second configuration800allows the front mount of a mounting configuration (e.g., the front mount404, etc.) to not intersect with the second outer guide vane802bor the third outer guide vane802c.

FIG.9A-Cillustrate a prior-art process900for removing the core turbine104of a gas turbine engine100using the first prior-art mounting configuration200ofFIG.2.FIG.9Aillustrates a first step902, which includes a decoupling904the mounts204,206and thrust linkage208and a removal906of the gas turbine engine100from the pylon202. The first step902can take a relatively large amount of time given the complexity of the decoupling904the mounts204,206and thrust linkage208and the need to secure the gas turbine engine100prior to the decoupling904.

FIG.9Billustrates a second step908of the prior process900. In the second step908, the gas turbine engine100, now removed from the pylon202, has been disposed on a carrier909. The carrier909allows the gas turbine engine100to be moved to a maintenance area to be inspected, serviced, and/or repaired.

FIG.9Cillustrated a third step910of the prior process900. In the third step910, a decoupling912of the fan section106of the gas turbine engine100and core turbine104occurs. The decoupling912can include the removal of the fasteners coupling the fan section106to the core turbine104. After the decoupling912, the individual parts and/or components (e.g., the HP compressor114, the combustion section116, the high pressure turbine118, the low pressure turbine120, etc.) of the core turbine104can be serviced. As such, to service parts of core turbine104of gas turbine engine100mounted using the first prior-art mounting configuration200, the entirety of the gas turbine engine100must be removed from the pylon202.

FIG.10A-Billustrate a process1000for removing the core section401of the gas turbine engine400ofFIG.4Ain accordance with teachings of this disclosure.FIG.10Aillustrates a first step1002, which includes a decoupling1004of the cantilevered core section401from the fan section106. The decoupling1004can include the removal of the fasteners coupling the fan section106to the core section401. As such, the core section401can be removed from the gas turbine engine400on the pylon402without the whole removal of the gas turbine engine400from the pylon402and the decoupling of the mounts404,406and thrust linkage408.

FIG.10Billustrates a second step1006of the process1000. In the second step1006, the core section401, now removed from the pylon402, has been disposed on a carrier1008. The carrier1008allows the gas turbine400to be moved to a maintenance area to be inspected, serviced, and/or repaired. When compared to the process900, the process1000enables the core section401of the gas turbine engine400be more easily serviced, inspected, etc. As such, the mounting configuration405reduces the time associated with servicing and inspecting the core section401. While the illustrated examples ofFIGS.10A and10Billustrated a ducted fan (e.g., the fan section106, etc.), the method described in conjunction withFIGS.10A-10Bare similarly applicable to gas turbine engines with unducted fan sections (e.g., a propfan engine, etc.).

FIG.11is a side view of a block diagram of a gas turbine engine1100depicting a mounting configuration1102. The simplified gas turbine engine1100includes a front frame1104a, a rear frame1104b, and an engine carcass1106. The example mounting configuration1102couples the gas turbine engine1100to the pylon402and includes a front mount1108, an aft mount1110, a first thrust linkage1112, and a second thrust linkage1114. The mounting configuration ofFIG.11enables the pitch moment generated by the operation of the gas turbine engine to be constrained by the thrust linkages1112,1114in combination, which thereby prevents the pitch moment from being transferred through the engine carcass1106.

InFIG.11, the front frame1104agenerally corresponds to the frame (e.g.,132, etc.) around a fan (e.g., the LP compressor112ofFIG.1, etc.), and the rear frame1104bgenerally corresponds to the frame surrounding the low pressure turbine (e.g., the LP turbine120, etc.). In other examples, the front frame1104acan correspond to any suitable location of the gas turbine engine1100and rear frame1104bcan correspond to any suitable location on the gas turbine engine1100downstream of the front frame1104a. The engine carcass1106(also referred to as the engine core1106) refers to internal components of the engine, including the flow path components (e.g., the LP compressor112, the high pressure compressor114, the combustion section116, the high pressure turbine118, and the low pressure turbine120, etc.) of the gas turbine engine1100.

InFIG.11, the front mount1108transfers vertical forces, lateral forces, and bending moments applied on the roll axis generated by the gas turbine engine1100to the pylon402. In some examples, the front mount1108can be implemented by a 3-pin linkage and a 2-pin linkage. In other examples, the front mount1108can be implemented by another suitable linkage and/or combination thereof. InFIG.11, the aft mount1110transfers lateral forces generated by the gas turbine engine1100to the pylon402. In some examples, the aft mount1110can be implemented by a 2-pin linkage. In other examples, the aft mount1110can be implemented by another suitable linkage and/or combination thereof. InFIG.11, the front mount1108and aft mount1110collectively react bending moments about the yaw axis, as both mounts1108,1110react lateral forces. As such, the yaw bending moments are transferred between the mounts1108,1110and through the engine carcass1106.

InFIG.11, the thrust linkages1112,1114transfer axial forces generated by the gas turbine engine1100to the pylon402. The attachment points1115a,1115bof the thrust linkages1112,1114on the pylon402are separated by a vertical displacement1116. The vertical displacement1116enables the thrust linkages1112,1114to bear different amounts of axial loads generated by the gas turbine engine1100. As such, this imbalance of axial forces between the thrust linkages1112,1114enables the thrust linkages to transfer pitch moments generated by the gas turbine engine1100to the pylon402. As such, in combination, the forward mount1108, the aft mount1110, and thrust linkages1112,1114constrain the six degrees of freedom of the gas turbine engine1100(e.g., vertical translation, lateral translation, axial translation, rotation about the yaw axis, rotation about the pitch axis, and rotation about the roll axis). The mounting configuration1102of the forward mount1108, the aft mount1110and thrust linkages1115a,1115bcause the gas turbine engine1100to be statically determinate.

In some examples, either or both of the thrust linkages1112,1114can be implemented by multiple thrust linkages (e.g., two thrust linkages, three thrust linkages, etc.). In some such examples, the plurality of thrust linkages1112can be joined together via a yoke and/or a whiffletree connection, which evenly distributes the load between each of the plurality of thrust linkages1112. In some such examples, the plurality of thrust linkages1114can be joined together via a yoke and/or whiffletree connection, which evenly distributes the load between each of the plurality of thrust linkages1114.

FIG.12is a top view of a block diagram of a simplified gas turbine engine1200depicting a first alternative mounting configuration1202. The simplified gas turbine engine1200includes the front frame1104aofFIG.11, the rear frame1104bofFIG.11, and the engine carcass1106ofFIG.11. The example mounting configuration1202couples the gas turbine engine1200to the pylon402and includes a front mount1204, an aft mount1206, a first thrust linkage1208, and a second thrust linkage1210. The mounting configuration1202enables the yaw moment generated by the operation of the gas turbine engine1200to be constrained by the thrust linkages1208,1210in combination, which prevents the yaw moment from being transferred through the engine carcass1106.

InFIG.12, the front mount1204transfers vertical forces, lateral forces, and bending moments applied on the roll axis generated by the gas turbine engine1200to the pylon402. In some examples, the front mount1204can be implemented by a 3-pin linkage and a 2-pin linkage. In other examples, the front mount1204can be implemented by another suitable linkage and/or combination thereof. InFIG.12, the aft mount1206transfers vertical forces generated by the gas turbine engine1200to the pylon402. In some examples, the aft mount1206can be implemented by a 2-pin linkage. In other examples, the aft mount1206can be implemented by another suitable linkage and/or combination thereof. InFIG.12, the front mount1204and aft mount1206collectively react bending moments about the pitch axis, as both mounts1204,1206react vertical forces. As such, the pitch bending moments are transferred between the mounts1204,1206and through the engine carcass1106.

InFIG.12, the thrust linkages1208,1210transfer axial forces generated by the gas turbine engine1200to the pylon402. The attachment points1214a,1214bof the thrust linkages1208,1210on the pylon402are separated by a lateral displacement1216. The lateral displacement1216enables the thrust linkages1208,1210to bear different amounts of axial loads generated by the gas turbine engine1200. As such, this imbalance of axial forces between the thrust linkages1208,1210enables the thrust linkages to transfer yaw moments generated by the gas turbine engine1200to the pylon202. As such, in combination, the forward mount1204, the aft mount1206, and thrust linkages1208,1210constrain the six degrees of freedom of the gas turbine engine1200(e.g., vertical translation, lateral translation, axial translation, rotation about the yaw axis, rotation about the pitch axis, and rotation about the roll axis). The mounting configuration1202of the forward mount1204, the aft mount1206and thrust linkages1214a,1214bcause the gas turbine engine1200to be statically determinate.

In some examples, either or both of the thrust linkages1208,1210can be implemented by multiple thrust linkages (e.g., two thrust linkages, three thrust linkages, etc.). In some such examples, the plurality of thrust linkages1208can be joined together via a yoke and/or a whiffletree connection, which evenly distributes the load between each of the plurality of thrust linkages1208. In some such examples, the plurality of thrust linkages1210can be joined together via a yoke and/or whiffletree connection, which evenly distributes the load between each of the plurality of thrust linkages1210.

FIGS.13A and13Bare a simplified top view and side view, respectively, of an example gas turbine engine1300depicting a second alternative mounting configuration1302. The gas turbine engine1300includes the front frame1104aofFIG.11, the rear frame1104bofFIG.11, and the engine carcass1106ofFIG.11. The example mounting configuration1202couples the gas turbine engine1300to the pylon402and includes a front mount1304, an aft mount1306, a first thrust linkage1308, a second thrust linkage1310, a third thrust linkage1312. The mounting configuration1302enables both yaw and pitch moments generated by the operation of the gas turbine engine1200to be constrained by the thrust linkages1308,1310,1312, which prevents the yaw moment from being transferred through the engine carcass1106.

InFIGS.13A and13B, the front mount1304transfers vertical force and bending moments applied on the roll axis generated by the gas turbine engine1300to the pylon402. In some examples, the front mount1304can be implemented by a 3-pin linkage. In other examples, the front mount1304can be implemented by another suitable linkage and/or combination thereof. InFIG.13, the aft mount1306transfers lateral forces generated by the gas turbine engine1300to the pylon402. Additionally or alternatively, the aft mount1306can transfer vertical force, lateral forces and/or bending moments applied on the roll axis generated by the gas turbine engine1300. In such examples, the front mount1304transfers the remaining of the vertical force, the lateral force and the bending moments. In some examples, the aft mount1306can be implemented by a 2-pin linkage. In other examples, the aft mount1306can be implemented by another suitable linkage and/or combination thereof.

InFIGS.13A and13B, the thrust linkages1308,1310,1312transfer axial forces generated by the gas turbine engine1300to the pylon402. The thrust linkages1308,1310,1312have attachment points1312a,1312b,1312cto the pylon402, respectively. The first and second attachment points1312a,1312bare vertical displaced from the attachment point1312cby a vertical displacement1314. Similarly, the first attachment point1312ais laterally displaced from the second attachment point1312bby a lateral displacement1316. The vertical displacement1314and the lateral displacements1316allow imbalances of axial forces to occur between the thrust linkages1308,1310,1312. As such, the thrust linkages1308,1310,1312can transfer yaw and pitch moments generated by the gas turbine engine1300to the pylon. In other examples, the thrust linkages1308,1310,1312can have any other suitable (e.g., having both vertical and lateral displacements, etc.). As such, in combination, the forward mount1304, the aft mount1306, and thrust linkages1308,1310,1312constrain the six degrees of freedom of the gas turbine engine1300(e.g., vertical translation, lateral translation, axial translation, rotation about the yaw axis, rotation about the pitch axis, and rotation about the roll axis). The mounting configuration1302of the forward mount1304, the aft mount1306and thrust linkages1312a,1312b,1312ccause the gas turbine engine1300to be statically determinate.

The examples disclosed herein negate and/or mitigate the distortions in the engine carcasses of gas turbine engines associated with bending moments generated from engine operation. Particularly, the mounting configuration405ofFIGS.4A and4Bminimizes the portion of the engine carcass subjected to these bending moments. Additionally, the mounting configuration405enables the use of the cantilever core section, which decreases the maintenance time and cost associated with servicing the cantilever core section when compared to prior art configurations. The mounting configurations1102,1202,1302inFIGS.11,12, and13cause yaw and/or pitch bending moments to be reacted between the thrust links of the gas turbine engine, which mitigate the distortions in the engine carcass associated with these bending moments.

Although certain example methods, apparatus and articles of manufacture have been disclosed herein, the scope of coverage of this patent is not limited thereto. On the contrary, this patent covers all methods, apparatus and articles of manufacture fairly falling within the scope of the claims of this patent.

Example methods, apparatus, systems, and articles of manufacture to mount a gas turbine engine to a pylon are disclosed herein.

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

1. An apparatus for mounting a gas turbine engine to a pylon, the gas turbine including an upstream section and a downstream section, the gas turbine defining a roll axis, a yaw axis, and a pitch axis, the apparatus comprising a first mount to couple the upstream section of the gas turbine engine to the pylon, a second mount to couple the upstream section of the gas turbine engine to the pylon, the second mount downstream of the first mount, and a thrust linkage to couple the upstream section to the pylon, wherein the downstream section is decouplable from the upstream section without decoupling the first mount, the second mount, and the thrust linkage.

2. An apparatus of any of the preceding clauses, wherein the upstream section includes a low pressure compressor, and the downstream section includes a high pressure compressor, a combustor, a high-pressure turbine, and a low-pressure turbine.

3. An apparatus of any of the preceding clauses, wherein the upstream section includes a low pressure compressor, and the downstream section includes a compressor, a combustor, and a turbine.

4. An apparatus of any of the preceding clauses, wherein a center of gravity of the gas turbine engine is between the first mount and the second mount, such that the upstream section is cantilevered from the downstream section.

5. An apparatus of any of the preceding clauses, wherein the first mount is coupled to a fan casing of the gas turbine engine and the second mount is coupled to an intermediate compressor casing of the gas turbine engine.

6. An apparatus of any of the preceding clauses, wherein the first mount surrounds a first outer guide vane of the gas turbine engine.

7. An apparatus of any of the preceding clauses, wherein the first outer guide vane is oriented along the yaw axis.

8. An apparatus of any of the preceding clauses, wherein the first mount is at a substantially the same position along the roll axis as a second outer guide vane of the gas turbine engine and a third outer guide vane of the gas turbine engine, the first mount disposed circumferentially between the second outer guide vane and the third outer guide vane.

9. An apparatus of any of the preceding clauses, wherein the second mount constrains rotation about the roll axis of the gas turbine, the second mount includes a first fastener disposed within the pylon, and a second fastener disposed within the pylon, the second fastener opposite the first fastener about the pylon.

10. An apparatus of any of the preceding clauses, wherein the first fastener forms a clevis with a boss of the pylon.

11. An apparatus of any of the preceding clauses, wherein the first mount includes at least one of a trunnion or a yoke, the first mount to constrain translation along the pitch axis of the gas turbine engine and translation along the yaw axis of the gas turbine engine.

12. A gas turbine engine defining a roll axis, a yaw axis, and a pitch axis, the gas turbine engine comprising a first section, a second section coupled to the first section, the second section downstream from the first section, a first mount to couple the first section of the gas turbine engine to the pylon, a second mount to couple the first section of the gas turbine engine to the pylon, the second mount downstream of the first mount, and a thrust linkage to couple the first section to the pylon, and wherein the second section can be decoupled from the upstream section without decoupling the first mount, the second mount, and the thrust linkage.

13. A gas turbine engine of any of the preceding clauses, wherein the first section includes a low pressure compressor and the second section includes a high pressure compressor, a combustor, a high-pressure turbine, and a low-pressure turbine.

14. A gas turbine engine of any of the preceding clauses, wherein the first section includes a low pressure compressor, and the second section includes a compressor, a combustor, and a turbine.

15. A gas turbine engine of any of the preceding clauses, wherein a center of gravity of the gas turbine engine is between the first mount and the second mount, such that the first section is cantilevered from the downstream section.

16. A gas turbine engine of any of the preceding clauses, wherein the first section includes a fan casing and an intermediate compressor casing, the first mount coupled to the fan casing and the second mount is coupled to the intermediate compressor casing.

17. A gas turbine engine of any of the preceding clauses, further including a first outer guide vane, the first mount surrounding the first outer guide vane.

18. A gas turbine engine of any of the preceding clauses, wherein the first outer guide vane is oriented along the yaw axis.

19. A gas turbine engine of any of the preceding clauses, wherein the first mount is at a substantially the same position along the roll axis of the gas turbine engine as a second outer guide vane of the gas turbine engine and a third outer guide vane of the gas turbine engine, the first mount disposed circumferentially between the second outer guide vane and the third outer guide vane.

20. A gas turbine engine of any of the preceding clauses, wherein the second mount constrains rotation about the roll axis, the second mount includes a first fastener disposed within the pylon, and a second fastener disposed within the pylon, the second fastener opposite the first fastener about the pylon.

21. A gas turbine engine of any of the preceding clauses, wherein the first fastener forms a clevis with a boss of the pylon.

22. A gas turbine engine of any of the preceding clauses, wherein the first mount includes at least one of a trunnion or a yoke, the first mount to constrain translation along the pitch axis of the gas turbine engine and translation along the yaw axis of the gas turbine engine.

23. An apparatus for mounting a gas turbine engine to a pylon, the apparatus comprising a first mount to couple the gas turbine engine to the pylon, a second mount to couple the gas turbine engine to the pylon, a first thrust linkage, and a second thrust linkage displaced along a first axis from the first thrust linkage, the first thrust linkage and the second thrust linkage to react a first moment generated during operation of the gas turbine engine.

24. An apparatus of any of the preceding clauses, wherein the first thrust linkage is vertically displaced from the second thrust linkage, and wherein the first moment is a moment about a pitch axis of the gas turbine engine.

25. An apparatus of any of the preceding clauses, wherein the first thrust linkage is laterally displaced from the second thrust linkage, and wherein the first moment is a moment about a yaw axis of the gas turbine engine.

26. An apparatus of any of the preceding clauses, further including a third thrust linkage displaced from the first thrust linkage along a second axis, the second axis perpendicular to the first axis, the third thrust linkage and the first thrust linkage to react a second moment, the second moment applied in a direction perpendicular to the first moment.

27. An apparatus of any of the preceding clauses, wherein the first moment is applied about a yaw axis of the gas turbine engine, and wherein the second moment is applied about a pitch axis of the gas turbine engine.

28. An apparatus of any of the preceding clauses, wherein at least one of the first thrust linkage or the second thrust linkage transfer forces applied along a roll axis to the pylon, at least one of the first mount or the second mount transfer forces applied along a pitch axis to the pylon, and at least one of the first thrust linkage or the second thrust linkage transfer forces applied along a yaw axis to the pylon.

29. An apparatus of any of the preceding clauses, wherein the first mount and the second mount are coupled to a fan section of the gas turbine engine.

30. An apparatus of any of the preceding clauses, wherein a core section of the gas turbine engine can be decoupled from a fan section of the gas turbine without decoupling the first mount and second mount from the pylon.

31. An apparatus of any of the preceding clauses, wherein the first mount includes a first fastener disposed within the pylon, and a second fastener disposed within the pylon, the second fastener opposite the first fastener.

32. An apparatus of any of the preceding clauses, wherein the first fastener forms a clevis with a boss of the pylon.

33. A gas turbine engine comprising a first section, a second section coupled to the first section, the second section downstream from the first section, a first mount to couple the first section to the pylon, a second mount to couple at least one of the first section or the second section to the pylon, a first thrust linkage, and a second thrust linkage displaced along a first axis from the first thrust linkage, the first thrust linkage and the second thrust linkage to react a first moment generated during operation of the gas turbine engine.

34. A gas turbine engine of any of the preceding clauses, wherein the first thrust linkage is vertically displaced from the second thrust linkage, and wherein the first moment is a moment about a pitch axis of the gas turbine engine.

35. A gas turbine engine of any of the preceding clauses, wherein the first thrust linkage is laterally displaced from the second thrust linkage, and wherein the first moment is a moment about a yaw axis of the gas turbine engine.

36. A gas turbine engine of any of the preceding clauses, wherein the apparatus further includes a third thrust linkage displaced from the first thrust linkage along a second axis, the second axis perpendicular to the first axis, the third thrust linkage and the first thrust linkage to react a second moment, the second moment applied in a direction perpendicular to the first moment.

37. A gas turbine engine of any of the preceding clauses, wherein the first moment is applied about a yaw axis of the gas turbine engine, and the second moment is applied about a pitch axis of the gas turbine engine.

38. A gas turbine engine of any of the preceding clauses, wherein at least one of the first thrust linkage or the second thrust linkage transfer forces applied along a roll axis to the pylon, at least one of the first mount or the second mount transfer forces applied along a pitch axis to the pylon, and at least one of the first thrust linkage or the second thrust linkage transfer forces applied along a yaw axis to the pylon.

39. A gas turbine engine of any of the preceding clauses, wherein a first mount and a second mount are coupled to the first section of the gas turbine engine.

40. A gas turbine engine of any of the preceding clauses, wherein the first section is a fan section, the second section is a core section, the second mount is disposed on the first section, and the core section decouplable from the fan section without decoupling the first mount and the second mount from the pylon.

41. A gas turbine engine of any of the preceding clauses, wherein the first mount includes a first fastener disposed within the pylon, and a second fastener disposed within the pylon, the second fastener opposite the first fastener.

42. A gas turbine engine of any of the preceding clauses, wherein the first fastener forms a clevis with a boss of the pylon.

The following claims are hereby incorporated into this Detailed Description by this reference, with each claim standing on its own as a separate embodiment of the present disclosure.