Gap control components

Abstract

A clearance control assembly for a gas turbine engine, the gas turbine engine defining axial and radial directions, and including a first-stage rotor blade and a shroud hanger. The assembly includes a housing configured to be radially outwardly positioned from the first-stage rotor blade when mounted in the gas turbine engine. The housing is also configured to engage with the shroud hanger in a first position when mounted in the gas turbine engine. The assembly also includes a baffle positioned radially outwardly from the housing to define a chamber therebetween. The baffle has a front end and a rear end. The front end of the baffle engages with the housing to form a first seal, and the rear end of the baffle engages with the housing to form a second seal. The baffle, the housing, or both define an inlet to allow fluid to enter the chamber, and the housing defines an outlet to allow fluid to exit the chamber.

Description

[0001] Federal government-funded research

[0002] This invention was completed with government support. The U.S. government may hold certain rights to this invention. Technical Field

[0003] This disclosure generally relates to gas turbine engines. More specifically, this disclosure relates to clearance control components for gas turbine engines. Background Technology

[0004] In a gas turbine engine, air is pressurized in a compressor and mixed with fuel in a combustor to produce hot combustion gases. Energy is extracted from the gases in a high-pressure turbine (HPT), which is connected to the compressor via a drive shaft.

[0005] In a typical turbofan aircraft engine, the fan is mounted upstream of the compressor and powered by a low-pressure turbine (LPT) downstream of the HPT. In marine and industrial (M&I) applications, the LPT can power an external drive shaft, thereby powering a propulsion system or generator.

[0006] The compression and combustion cycle introduces energy into the pressurized air, where energy is extracted from the combustion gases in the turbine stage. Because the HPT is affected by the hottest combustion gases emitted from the combustor, various components of the HPT are typically cooled by venting a portion of the pressurized air from the compressor.

[0007] LPT and HPT may include a first-stage turbine rotor blade extending radially from a supporting rotor disk, wherein the radially outer tip of the blade is mounted within a surrounding shroud. The shroud is stationary and supported by a surrounding annular housing for maintaining a small radial clearance or gap between the tip of the rotor blade and the shroud.

[0008] Turbine blades share a common airfoil profile, which is typically designed to maximize the efficiency of extracting energy from the combustion gases. Leakage of combustion gases at the blade tip clearance reduces engine efficiency. Therefore, the radial blade tip clearance should be as small as possible, but not too small, otherwise undesirable friction between the blade tips and the turbine shroud can lead to unwanted damage or shorten component life.

[0009] To avoid undesirable blade tip friction against the shroud, the blade tip clearance must be sufficiently large. However, to improve overall engine efficiency, the blade tip clearance should be minimized. Therefore, clearance control components can be provided to help manage the clearance between the blade tips and the surrounding shroud during various power settings and flight conditions. The inventors of this disclosure have proposed various constructions and devices to improve upon currently known clearance control components. Attached Figure Description

[0010] The complete and practical disclosure of the invention, including its preferred mode, is set forth in the description with reference to the accompanying drawings, for those skilled in the art, wherein:

[0011] Figure 1 This is a cross-sectional view of a gas turbine engine according to an exemplary aspect of this disclosure.

[0012] Figure 2 This is a cross-sectional view of a clearance control component according to an exemplary aspect of this disclosure.

[0013] Figure 3 This is a cross-sectional view of a clearance control component according to an exemplary aspect of this disclosure.

[0014] Figure 4 This is a cross-sectional view of a clearance control component according to an exemplary aspect of this disclosure.

[0015] Figure 5 This is a cross-sectional view of a clearance control component according to an exemplary aspect of this disclosure.

[0016] Figure 6 This is a perspective view of a gap control component according to an exemplary aspect of this disclosure.

[0017] Figure 7 Based on exemplary aspects of this disclosure Figure 6 A three-dimensional view of a portion of the gap control component.

[0018] Figure 8 Based on exemplary aspects of this disclosure Figure 6 A side view of a portion of the gap control component.

[0019] Figure 9 This is a side view of a clearance control component according to an exemplary aspect of this disclosure.

[0020] Figure 10 This is a cross-sectional view of a clearance control component according to an exemplary aspect of this disclosure. Detailed Implementation

[0021] Reference will now be made in detail to the present embodiments of the invention, one or more examples of which are illustrated in the accompanying drawings. The detailed description uses numerals and letter reference numerals to denote features in the drawings. Similar or analogous reference numerals in the drawings and description have been used to denote similar or analogous portions of the invention.

[0022] The term "exemplary" is used herein to mean "serving as an example, instance, or illustration." Any implementation described herein as "exemplary" is not necessarily to be construed as superior or better than other implementations. Furthermore, unless explicitly stated otherwise, all embodiments described herein should be considered exemplary.

[0023] As used herein, the terms “first,” “second,” and “third” are used interchangeably to distinguish one component from another and are not intended to indicate the location or importance of the individual components.

[0024] The terms "front" and "rear" refer to relative positions within a gas turbine engine or vehicle, and specifically to the normal operating posture of the gas turbine engine or vehicle. For example, in the case of a gas turbine engine, "front" refers to the position closer to the engine inlet, while "rear" refers to the position closer to the engine nozzle or exhaust port.

[0025] 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 the fluid flows, and "downstream" refers to the direction from which the fluid flows.

[0026] The term "fluid" can refer to either a gas or a liquid. The term "fluid connectivity" refers to the ability of fluids to establish connections between specified areas.

[0027] Unless otherwise stated herein, the terms “connection,” “fixed,” “attached to,” etc., refer to direct connection, fixing, or attachment, as well as indirect connection, fixing, or attachment via one or more intermediate parts or features. Similarly, unless otherwise stated herein, the term “joint” refers to direct jointing or jointing via one or more intermediate parts or features.

[0028] Unless the context clearly indicates otherwise, the singular forms “a,” “a,” and “the” include plural references.

[0029] As used throughout the specification and claims, approximate language is applied to modify any quantitative expression that may allow for variation without altering its underlying function. Therefore, values ​​modified by terms such as “about,” “approximately,” and “substantially” are not limited to specified precise values. In at least some cases, approximate language may correspond to the precision of the instrument used to measure the value, or the precision of the method or machine used to construct or manufacture the component and / or system. For example, approximate language may refer to margins of 1%, 2%, 4%, 10%, 15%, or 20%. These approximate margins may apply to a single value, to either or both endpoints of a defined numerical range, and / or to the margin of the range between the endpoints.

[0030] Throughout this specification and claims, scope limitations are combined and interchanged, and unless the context or language otherwise indicates otherwise, such scopes are identified and include all subscopes contained herein. For example, all scopes disclosed herein include endpoints, and endpoints may be combined independently of each other.

[0031] According to one or more embodiments described herein, a gas turbine engine may be equipped with one or more clearance control components. Clearance control components may be provided to optimize, maintain, or adjust the clearance between the rotor blade tips and the shroud. The clearance control components can optimize, maintain, or adjust the clearance by adjusting the amount of relatively cold fluid supplied to the housing surrounding the shroud. The clearance control components can passively optimize, maintain, or adjust the clearance by reducing thermal capacity mismatch and optimizing the thermal time constant between the rotor blade stage and the stationary shroud, allowing the clearance between the rotor blade stage and the shroud to be passively controlled. Equipping a gas turbine engine with clearance control components can have the benefit of improving engine efficiency by reducing the clearance between the rotor blade tips and the shroud. Improved engine efficiency can result in additional engine power output and reduced fuel consumption. Furthermore, equipping a gas turbine engine with clearance control components has the benefit of reducing the likelihood of rotor blade contact with the shroud, thereby reducing the possibility of engine damage. Additionally, equipping a gas turbine engine with clearance control components allows for passive control of the clearance between the rotor blades and the shroud in the event of a failure of the active clearance control system.

[0032] In at least one embodiment, the clearance control assembly includes a housing configured to be radially outwardly positioned from the first-stage rotor blades when mounted in a gas turbine engine. The housing is also configured to engage with a shroud hanger at a first location when mounted in the gas turbine engine. The clearance control assembly also includes a baffle positioned radially outwardly from the housing to form a chamber between the baffle and the housing. The baffle has a front end and a rear end. The front end of the baffle engages with the housing to form a first seal, and the rear end of the baffle engages with the housing to form a second seal. The baffle or housing defines an inlet to allow fluid to enter the chamber, and the housing defines an outlet to allow fluid to exit the chamber.

[0033] As will be understood from the discussion herein, engaging the front end of the baffle with the housing to form a first seal and engaging the rear end of the baffle with the housing to form a second seal results in axial and radial sealing of the chamber. The advantage of axial and radial sealing is that it allows fluid entering the chamber to impinge on and move along the housing until it exits the chamber, which can increase the cooling of the housing and shroud via convection. Furthermore, the fluid can provide more uniform cooling to the housing. Additionally, this configuration allows for sealing with low stress throughout all operations.

[0034] In at least one embodiment, the outlet defined by the housing is positioned to allow fluid to exit the chamber at a location downstream of the first position. This configuration has the additional benefit of cooling components downstream of the rotor blade stage (e.g., subsequent nozzles).

[0035] In at least one embodiment, the first seal includes a first rope sealing element positioned between the front end of the baffle and the housing, and the second seal includes a second rope sealing element positioned between the rear end of the baffle and the housing. This configuration has the additional benefit of increasing the sealing effect at the locations of the first and second seals, which can further increase the cooling of the housing and shroud via convection. Furthermore, this can further increase the amount of fluid leaving the outlet due to less undesirable fluid escape from the system, which can further increase the cooling of components downstream of the rotor blade stage (e.g., subsequent nozzles).

[0036] In at least one embodiment, the front or rear end of the baffle engages with a flange extending radially outward from the housing to at least partially form a first or second seal. This configuration has the additional benefit of increasing the sealing effect at the locations of the first and second seals, which can further increase the cooling of the housing and shroud via convection. Furthermore, this can further increase the amount of fluid leaving the outlet due to less undesirable fluid escape from the system, which can further increase the cooling of components behind the rotor blade stage (e.g., subsequent nozzles).

[0037] In at least one embodiment, the shroud hanger has a rear hook configured to match a corresponding feature of the housing, with a first position being the position where the rear hook of the shroud hanger matches the corresponding feature of the housing. This configuration has the additional benefit of cooling components behind the rotor blade stage (e.g., subsequent nozzles).

[0038] In at least one embodiment, the chamber extends continuously from the front end of the baffle to the rear end of the baffle. An additional benefit of this configuration is the increased amount of cooled housing surface area, which may enhance the cooling of the shroud.

[0039] In at least one embodiment, the clearance control assembly includes a conductive element positioned on the outer surface of the housing and within the housing. An additional benefit of this configuration is the ability to set the housing's time constant to match the rotor blade stage time constant by adjusting the mass thickness of the conductive element in the axial, radial, and / or circumferential directions. Matching the time constant increases the clearance control assembly's ability to passively control the clearance between the rotor blade tip and the shroud.

[0040] In at least one embodiment, the housing has a flange extending radially outward and located between the front and rear ends of the baffle. An additional benefit of this configuration is the ability to set the housing's time constant to match the rotor blade stage's time constant by adjusting the mass of the flange in the axial, radial, and / or circumferential directions. Matching the housing's time constant to the rotor blade stage's time constant allows for passive control of the clearance between the rotor blade stage and the shroud. Furthermore, this configuration increases the housing's surface area, allowing for faster cooling of the housing, which in turn allows for faster cooling of the shroud.

[0041] In at least one embodiment, the flange has a recess located near the flange root. An additional benefit of this configuration is reduced conduction into the flange, making them more isothermal or temperature-uniform. Making the flange more isothermal or temperature-uniform can improve housing roundness and reduce thermal growth of the housing. Reducing thermal growth of the housing can reduce thermal capacity mismatch and optimize the thermal time constant between the rotor blade stages and the stationary shroud, thereby allowing passive control of the clearance between the rotor blade stages and the shroud.

[0042] Referring now to the accompanying drawings, where the same numbers represent the same elements throughout all the drawings. Figure 1 This is a schematic cross-sectional view of a gas turbine engine according to an exemplary embodiment of the present disclosure. More specifically, for Figure 1 In one embodiment, the gas turbine engine is a high-bypass turbofan jet engine, referred to herein as "turbofan engine 10". Figure 1 As shown, the turbofan engine 10 defines an axial direction A (extending parallel to a longitudinal centerline 12 for reference), a radial direction R, and a circumferential direction C. Typically, the turbofan engine 10 includes a fan section 14 and a turbine 16 disposed downstream of the fan section 14.

[0043] The depicted exemplary turbine 16 generally includes a substantially tubular housing 18 defining an annular inlet 20. The housing 18 surrounds, in a series flow relationship: a compressor section including a boost or low-pressure (LP) compressor 22 and a high-pressure (HP) compressor 24; a combustion section 26; a turbine section including a high-pressure (HP) turbine 28 and a low-pressure (LP) turbine 30; and an exhaust nozzle section 32. A high-pressure (HP) shaft or spool 34 drives the HP turbine 28 to the HP compressor 24. A low-pressure (LP) shaft or spool 36 drives the LP turbine 30 to the LP compressor 22. The compressor section, combustion section 26, turbine section, and nozzle section 32 together define a core airflow path 37.

[0044] For the depicted embodiment, fan section 14 includes a fan 38 having a plurality of fan blades 40 spaced apart and coupled to a rotor disk 42. As shown, the fan blades 40 extend generally radially outward from the rotor disk 42. The disk 42 is covered by a rotatable front hub 48, which is aerodynamically shaped to facilitate airflow through the plurality of fan blades 40. Furthermore, the exemplary fan section 14 includes an annular fan housing or outer nacelle 50 circumferentially surrounding at least a portion of the fan 38 and / or turbine 16. It should be understood that the nacelle 50 is supported relative to the turbine 16 by a plurality of circumferentially spaced outlet guide vanes 52. Additionally, a downstream section 54 of the nacelle 50 extends over the outer portion of the turbine 16 to define a bypass airflow passage 56 therebetween.

[0045] During operation of the turbofan engine 10, a certain amount of air 58 enters the turbofan engine 10 through the nacelle 50 and / or the relevant inlet 60 of the fan section 14. As the certain amount of air 58 passes through the fan blades 40, a first portion of the air 58, as indicated by arrow 62, is directed or directed into the bypass airflow passage 56, and a second portion of the air 58, as indicated by arrow 64, is directed or directed into the core airflow path 37, or more specifically, into the LP compressor 22. The ratio between the first portion of air 62 and the second portion of air 64 is commonly referred to as the bypass ratio. Then, as the second portion of air 64 is directed through the HP compressor 24 and into the combustion section 26, the pressure of the second portion of air 64 increases, where it mixes with fuel and burns to provide combustion gases 66.

[0046] Combustion gas 66 is directed through HP turbine 28, where a portion of the thermal and / or kinetic energy from the combustion gas 66 is extracted via a successive stage of HP turbine stator blades 68 connected to housing 18 and HP turbine rotor blades 70 connected to HP shaft or spool 34, thus rotating HP shaft or spool 34 to support the operation of HP compressor 24. Combustion gas 66 is then directed through LP turbine 30, where a second portion of the thermal and kinetic energy is extracted from the combustion gas 66 via a successive stage of LP turbine stator blades 72 connected to housing 18 and LP turbine rotor blades 74 connected to LP shaft or spool 36, thus rotating LP shaft or spool 36 to support the operation of LP compressor 22 and / or the rotation of fan 38.

[0047] Combustion gas 66 is then directed through the injector exhaust nozzle section 32 of turbine 16 to provide propulsive thrust. Simultaneously, the pressure of the first portion of air 62 increases significantly as it is directed through bypass airflow passage 56 before exiting from the nozzle exhaust section 76 of fan 38 of turbofan engine 10, also providing propulsive thrust. HP turbine 28, LP turbine 30, and injector exhaust nozzle section 32 at least partially define a hot gas path 78 for directing combustion gas 66 through turbine 16.

[0048] However, it should be understood that Figure 1The exemplary turbofan engine 10 depicted is merely an example, and in other exemplary embodiments, the turbofan engine 10 may have any other suitable configuration. For example, in other exemplary embodiments, the fan 38 may be configured as a variable pitch fan, including, for example, suitable actuation components for rotating a plurality of fan blades about a respective pitch axis, and the turbofan engine 10 may be configured as a geared turbofan engine having a reduction gearbox, etc., between the LP shaft 36 and the fan section 14. It should also be understood that, in other exemplary embodiments, aspects of this disclosure may be incorporated into any other suitable gas turbine engine. For example, in other exemplary embodiments, aspects of this disclosure may be incorporated into, for example, a turboprop engine.

[0049] Figure 2 This is a cross-sectional view of a clearance control assembly 100 according to an exemplary embodiment of the present disclosure. The clearance control assembly 100 includes a housing 140 configured to be installed in a gas turbine engine (e.g., Figure 1 In a gas turbine engine, the housing 140 is positioned radially R outward from the first-stage rotor blade 110. The housing 140 is also configured to engage with the shroud hanger 130 at a first position 150. In this example, the first position 150 is the final position where the housing 140 and the shroud hanger 130 are engaged. More specifically, in this example, the first position 150 is the position where the rear hook 133 of the shroud hanger 130 engages with the corresponding feature 143 of the housing 140. The housing 140 may also engage with other portions of the shroud hanger 130, such as the front end 138 of the shroud hanger 130.

[0050] The shield hanger 130 can engage with the shield 120. In at least one example, the shield 120 and the shield hanger 130 are a single component; however, as shown, the shield 120 and the shield hanger 130 can be two separate components. The shield 120 and the shield hanger 130 can extend circumferentially about an axis defined by the engine (e.g., the longitudinal centerline 12 of the engine 10). The engine may include multiple shield 120 assemblies, which include the shield 120 and the shield hanger 130 extending about a circumference defined by the rotor blades 110.

[0051] The shroud 120 has a hot side 121 in thermal communication with a hot combustion gas flow H (e.g., hot gas exhaust from a combustor) and a cold side 122 opposite to the hot side 121. The shroud 120 is statically mounted in the engine and surrounds the radially outer tips of the rotor blades 110. The shroud 120 may be spaced apart from the tips of the rotor blades 110 to define a radial clearance D.

[0052] The clearance control assembly 100 also includes a baffle 180 positioned radially R outward from the housing 140 to form a chamber 160 therebetween. The baffle 180 may be made of sheet metal and may be rolled into a desired shape. The baffle 180 has a front end 181 and a rear end 183 that both engage with the housing 140. The front end of the baffle 180 engages with the housing 140 to form a first seal 101, and the rear end of the baffle 180 engages with the housing 140 to form a second seal 102. The first seal 101 and the second seal 102 prevent fluid from escaping the chamber at the locations of the first seal 101 and the second seal 102.

[0053] In this example, chamber 160 extends continuously from the front end 181 of baffle 180 to the rear end 183 of baffle 180. Furthermore, chamber 160 extends continuously around housing 140 in the circumferential direction C. In this way, chamber 160 is generally cylindrical with tapered edges.

[0054] Still referencing Figure 2 In one example, both the front end 181 and the rear end 183 of the baffle 180 engage with flanges 147a and 147d, which extend radially outward from the housing 140 to at least partially form a first seal 101 or a second seal 102. However, in other examples, only one of the front end 181 or the rear end 183 of the baffle 180 engages with flange 147, which extends radially outward from the housing 140 to at least partially form a first seal 101 or a second seal 102. The baffle 180 may abut against the flange 147 to induce a spring force to form the first seal 101 or the second seal 102. The spring force may be induced by abutting against the flange 147 in the axial direction A.

[0055] Baffle 180 defines inlet 185 to allow fluid (e.g., air discharged from the compressor section of the engine or air from bypass airflow passage 56) to enter chamber 160. Inlet 185 may be an impingement inlet 185 to provide discrete impingement fluid jets in the radial direction R to chamber 160 and to the outer surface 141 of housing 140. Fluid upstream of inlet 185 may be at a higher pressure than fluid downstream of inlet 185 and within chamber 160. Therefore, as fluid exits inlet 185, it expands and is cooled.

[0056] The baffle 180 may define a plurality of inlets 185 extending circumferentially around the baffle 180. Each of the plurality of inlets 185 may be arranged at the same axial location; however, in other examples, the inlets 185 may be arranged such that they are located at different axial locations. For example, the inlets 185 may be staggered around the baffle 180. In this example, the inlets 185 are positioned near the front end 181 of the baffle 180. Such a configuration may allow cooling along a greater length of the housing 140.

[0057] However, in other exemplary embodiments of this disclosure, other configurations exist; for example, inlet 185 may be positioned near the center of baffle 180 to concentrate cooling, for example, at the center and rear of the housing. In another example, inlet 185 may be positioned near the rear end 183 of baffle 180 to concentrate cooling, for example, at the rear of housing 140, which may be desirable for some hanger configurations. In other examples, inlet 185 may be positioned near the front end 181 of baffle 180, and another inlet 185 may be positioned near the center of baffle 180 (see other examples below).

[0058] The term "closest" used throughout the document refers to the closest relationship between a component and a specified location. For example, "closest to the front" means closer to the front end than the center or back end; "closest to the center" means closer to the center than the front end or back end.

[0059] In this example, housing 140 defines outlet 145 to allow fluid to exit chamber 160. Furthermore, in this example, outlet 145 is located behind the first position 150 and extends from the outer surface 141 of housing to the inner surface of housing. In some examples, the fluid pressure within chamber 160 is higher than the fluid pressure downstream of outlet 145. Therefore, as fluid exits chamber 160 through outlet 145, the fluid rapidly expands and cools.

[0060] As shown, outlet 145 extends through housing 140 at an obtuse angle relative to the surface of housing 140 facing chamber 160. However, in other examples, outlet 145 extends through housing 140 at a perpendicular angle, and in other examples, outlet 145 extends through housing 140 at an acute angle relative to the surface of housing 140 facing chamber 160. In this example, positioning outlet 145 to allow fluid to exit chamber 160 at a location subsequent to first position 150 can provide additional cooling to first position 150. For example, when first position 150 is the final position of engagement between housing 140 and shroud hanger 130, outlet 145 can provide additional cooling to the final engagement position of housing 140 and shroud hanger 130. Additionally, additional cooling can be provided to subsequent nozzles (not shown). The fluid pressure within chamber 160 can be greater than the fluid pressure within the cavity located subsequent to first position 150. Therefore, as fluid exits chamber 160, the fluid pressure drops rapidly, causing the fluid to expand and resulting in a decrease in fluid temperature.

[0061] However, it should be understood that in other examples, outlet 145 may be positioned at other suitable locations to obtain other desired benefits. For example, in other embodiments, outlet 145 may alternatively extend through baffle 180.

[0062] The housing 140 may define a plurality of outlets 145 spaced circumferentially around the housing 140. Each of the plurality of outlets 145 may be arranged at the same axial position; however, in other examples, the outlets 145 may be arranged such that they are arranged at different axial positions. For example, the outlets 145 may be in staggered positions around the housing 140.

[0063] As described above, the different rates of thermal expansion between the rotor blades and the shroud 120 can alter the radial clearance D during various operating modes of the gas turbine engine. Therefore, the clearance control assembly 100 can selectively cool or heat the housing 140, the shroud hanger 130, and the shroud 120 to adjust the radial clearance D. For example, since the housing 140 engages with the shroud hanger 130, which engages with the shroud 120, or is a single component having the shroud 120, selective cooling or heating of the housing 140 also selectively cools or heats the shroud 120, for example, via conduction. Selective cooling or heating of the shroud 120 affects the radial clearance D. More specifically, cooling the housing 140 causes thermal contraction of the housing 140, the shroud hanger 130, and the shroud 120, which reduces the radial clearance D. Allowing the housing 140 to heat causes thermal expansion of the housing 140, the shroud hanger 130, and the shroud 120, which increases the radial clearance D.

[0064] In operation, fluid (e.g., air discharged from the compressor section of the engine or air from the bypass airflow passage 56) enters chamber 160 through inlet 185 of baffle 180. To cool shroud 120, the fluid temperature is lower than that of shroud 120. The relatively cool fluid is directed toward the outer surface 141 of housing 140, which conducts cooling to housing 140 and also to shroud hangers 130 and shroud 120. The fluid then exits chamber 160 through outlet 145. To heat shroud 120, or more precisely, to increase the temperature of shroud 120, the amount of relatively cool fluid supplied to chamber 160 can be reduced.

[0065] Figure 3 This is a cross-sectional view of a gap control component 100 according to another exemplary embodiment of the present disclosure. Figure 3 The components are basically similar to Figure 2 The components, and similar elements will be indicated by the same reference numerals. However, Figure 3 Components and Figure 2The difference in the components lies in that the housing 140 includes a first flange 147b and a second flange 147c located within the chamber 160. Furthermore, the shape of the baffle 180 conforms to the external dimensional shape of the housing 140. In this example, the baffle 180 is spaced apart from the housing 140 from the front end 181 to the rear end 183, such that the baffle 180 does not contact the housing 140 except at the locations of the first seal 101 and the second seal 102. The distance from the baffle 180 to the housing 140 can vary. For example, as shown, flanges 147b and 147c each define a tip at an outer position in the radial direction R. The distance from the tips of the flanges 147b and 147c to the baffle 180 can be less than the distance from the housing 140 to the center of the baffle 180. In other examples, the distance from the baffle 180 to the housing 140 is constant along the entire length of the baffle 180, except for the front end 181 and the rear end 183.

[0066] The housing 140 may include more than two flanges 147. For example, the housing 140 may include three, four, six or more flanges 147. The housing 140 may also include a single flange 147. Each flange 147 may extend continuously around the housing 140 in the circumferential direction C to reinforce the housing 140. However, in other examples, the flange 147 may extend only partially around the housing 140.

[0067] Since flange 147 is located within chamber 160, fluid flowing through chamber 160 can take a serpentine path axially through chamber 160. Additionally, as shown in the figure, Figure 3 The baffle 180 shown may define a plurality of inlets 185 spaced apart along an axial direction A. In particular, the exemplary baffle 180 depicted defines an inlet 185a positioned near the front end of the baffle 180, and two additional inlets 185b and 185c positioned near the center of the baffle 180. Furthermore, even if not shown in the cross-sectional view, the plurality of inlets 185a, 185b, 185c may extend circumferentially around the baffle 180 at or around the same axial location.

[0068] Flange 147 can increase the mass and surface area of ​​housing 140. Increasing the mass and surface area of ​​housing 140 can reduce the thermal capacity mismatch between rotor blade stage 110 and stationary shroud 120. The reduction in thermal capacity mismatch can optimize the thermal time constant between rotor blade stage 110 and stationary shroud 120, so that the gap D between rotor blade stage 110 and shroud 120 can be passively controlled.

[0069] Now for reference Figure 4 A cross-sectional view of a gap control assembly 100 according to yet another exemplary embodiment of the present disclosure is provided. Figure 4 The components are basically similar to Figure 3The components, and similar elements will be indicated by the same reference numerals. However, Figure 4 Components and Figure 3 The difference in the components is that the first and second flanges 147b, 147c located within the chamber 160 have a recess 148 located near the root end of the flange 147 (i.e., the inner end of the flanges 147b, 147c in the radial direction R where they meet the outer surface 141 of the housing 140). In this example, the recess 148 is fan-shaped and located near the underside of the flange 147.

[0070] Integrating the recess 148 into the flange 147 reduces conduction into the flange 147, making them more isothermal or temperature-uniform. Making the flange 147 more isothermal or temperature-uniform improves the roundness of the housing and reduces thermal growth in the housing 140. Reducing thermal growth in the housing 140 reduces heat capacity mismatch and optimizes the thermal time constant between the rotor blade stage 110 and the stationary shroud 120, allowing the gap D between the rotor blade stage 110 and the shroud 120 to be passively controlled.

[0071] Figure 5 This is a cross-sectional view of a gap control assembly 100 according to yet another exemplary embodiment of the present disclosure. Figure 5 The components are basically similar to Figure 2 The components, and similar elements will be indicated by the same reference numerals. However, Figure 5 Components and Figure 2 The difference in the components is that the conductive element 149 is positioned on the outer surface 141 of the housing 140 and within the chamber 160. The conductive element 149 can be configured to increase the time constant of the housing 140 to more closely approximate or match the time constant of the rotor blades 110. Designing the time constant of the housing 140 to match or more closely approximate the time constant of the rotor blades 110 can be achieved by adjusting the mass thickness of the conductive element 149 in the axial, radial, and / or circumferential directions C.

[0072] The conductive element 149 may be formed of a material different from that of the housing 140. Alternatively, the conductive element 149 may be formed of the same material as the housing 140. The conductive element 149 may be a single component of the housing 140. The conductive element 149 may be formed of a metal or metal alloy, or any other material having a relatively high heat capacity, to facilitate the conductive transfer of heat to or from the conductive element 149. For example, in some exemplary aspects, the conductive element 149 may be a nickel or cobalt-based alloy. In other examples, the conductive element 149 may define the same or similar heat capacity as a nickel or cobalt-based alloy.

[0073] exist Figure 5In the example, baffle 180 defines an inlet 185a positioned near the front end 181 of baffle 180, an inlet 185b positioned near the center of baffle 180, and an inlet 185c positioned near the rear end 183 of baffle 180. The plurality of inlets 185 may be circumferentially spaced around baffle 180 at or around each of these axial positions.

[0074] Figures 6 to 8 This is a view of the gap control component 100 according to an exemplary embodiment of the present disclosure. More specifically, Figure 6 It's a 3D image. Figure 7 It is a partial 3D image. Figure 8 This is a partial side view of the gap control assembly 100 according to an exemplary embodiment of the present disclosure. Figures 6 to 8 The components are similar to Figure 2 The components, and similar elements will be indicated by the same reference numerals.

[0075] More specifically, first refer to Figure 6 It should be understood that the clearance control assembly 100 includes a baffle 180 that extends substantially continuously along the circumferential direction C. In this example, the baffle 180 is a multi-piece design having multiple segments, such as segment 186 and segment 187, attached to each other at joints (e.g., joint 188 or joint 189). In particular, for the illustrated embodiment, the baffle 180 is a two-piece design having a first segment 186 and a second segment 187 attached to each other at a first joint 188 and a second joint 189.

[0076] Now for special reference Figure 7 A close-up view of the first connector 188 is provided. It should be understood that the first segment 186 of the baffle 180 includes a first flange 184a, and the second segment 187 of the baffle 180 includes a second flange 184b. In the illustrated embodiment, the first connector 188 is formed by the first and second flanges 184a, 184b of the first and second segments 186, 187, and is more specifically configured as a bolted connection, wherein the first and second flanges 184a, 184b of the first and second segments 186, 187 are mechanically connected by one or more fasteners 190 (e.g., by one or more bolts).

[0077] More specifically, here is a brief reference. Figure 8Provided as a close-up view of a portion of a first joint 188 along axial direction A, it should be understood that exemplary embodiments of the depicted assembly further include first and second inner supports 105a, 105b and first and second outer supports 106a, 106b. The inner supports 105a, 105b and / or the outer supports 106a, 106b can improve the radial seal of the baffle 180. Specifically, the first inner supports and outer supports 105a, 106a are positioned on opposite sides of the first flange 184a of the first segment 186 of the baffle, and the second inner supports and outer supports 105b, 106b are positioned on opposite sides of the second flange 184b of the second segment 187 of the baffle. The first and second inner supports 105a and the first and second outer supports 106b can minimize stress on the first and second flanges 184a, 184b of the baffle 180.

[0078] However, it should be understood that the exemplary baffle depicted is provided by way of example only, and in other embodiments, the baffle may be attached in any suitable manner. For example, baffle 180 may include any suitable number of segments attached in any suitable manner (e.g., by welding). However, in contrast to welding, these segments are fastened (e.g., ... Figure 7 (As shown in the figure) can reduce the stress at the point where adjacent sections meet.

[0079] Still referencing Figure 7 and Figure 8 As shown in the figure, the baffle 180 also includes a plurality of recesses 182. The recesses 182 allow the baffle 180 to remain radially flat between the flanges 147a and 147b, and can additionally help reduce vibration of the baffle 180.

[0080] Now for reference Figure 9 This shows a side view of a portion of a clearance control assembly 100 according to an exemplary aspect of this disclosure. Figure 9 As best shown in the illustrated embodiment, the first seal 101 includes a sealing element, and more specifically, includes a first rope seal 103 element positioned between the front end 181 of the baffle 180 and the housing 140. Similarly, the second seal 102 includes a sealing element, and more specifically, includes a second rope seal 104 element positioned between the rear end 183 of the baffle 180 and the housing 140. Additional flanges 147 may be provided inside the first rope seal 103 element and the second rope seal 104 element to hold the rope seal elements in place.

[0081] As shown in the figure, inlet 185 (which may be an impact inlet 185) is positioned near the front end 181 of baffle 180. Multiple inlets 185 can surround baffle 180. Figure 7Circumferential positioning. In other examples, the inlet 185 may additionally or alternatively be positioned near the center of the baffle 180 and / or the rear end of the baffle 180.

[0082] The outlet 145 is located behind the first position 150 and extends from the outer surface 141 of the housing to the inner surface 142 of the housing. Multiple outlets 145 may be circumferentially positioned around the housing 140. In this example, the outlet 145 extends through the housing 140 at a perpendicular angle to the outer surface 141 of the housing 140 facing the chamber 160. However, in other examples, the outlet 145 extends through the housing 140 at an obtuse angle, and in other examples, the outlet 145 extends through the housing 140 at an acute angle to the surface 141 of the housing 140 facing the chamber 160.

[0083] Still roughly for reference Figures 6 to 8 Implementation examples and Figure 9 In an embodiment similar to the previous example, the clearance control assembly 100 includes a housing 140 configured to be installed in a gas turbine engine (e.g., Figure 1 In a gas turbine engine, the rotor is positioned radially outward from the first-stage rotor blade 110 (not shown). For example, refer to the special reference. Figure 7 The housing 140 is further configured to engage with the shield hanger 130 at a first position 150. In this example, the first position 150 is the final engagement position of the housing 140 and the shield hanger 130. More specifically, the first position 150 is the position where the rear hook 133 of the shield hanger 130 engages with the corresponding feature 143 of the housing 140. The housing 140 may also engage with other portions of the shield hanger 130 (e.g., the front end of the shield hanger 130). The shield hanger 130 may engage with a shield 120 (not shown).

[0084] A baffle 180 of the clearance control assembly 100 is positioned radially R outward from the housing 140 to form a chamber 160 therebetween. The baffle 180 may be made of sheet metal and may be rolled into a desired shape. The baffle 180 has a front end 181 and a rear end 183 that both engage with the housing 140. The front end of the baffle 180 engages with the housing 140 to form a first seal 101, and the rear end of the baffle 180 engages with the housing 140 to form a second seal 102. In this example, the chamber 160 extends continuously from the front end of the baffle 180 to the rear end of the baffle 180. Furthermore, the chamber 160 extends continuously around the housing 140 in the circumferential direction C. In this way, the chamber 160 is generally cylindrical with rounded edges on its inner side.

[0085] Figure 10 This is a cross-sectional view of a gap control assembly 100 according to yet another exemplary embodiment of the present disclosure. Figure 10 The components are similar to Figure 2The components, and similar elements will be indicated by the same reference numerals. In this example, the clearance control assembly 100 includes a baffle 180 positioned radially R outward from the housing 140 to form a chamber 160 therebetween. The baffle 180 has a front end 181 and a rear end 183, both engaging with the housing 140. The front end 181 of the baffle 180 engages with a flange 147a of the housing 140 to form a first seal 101, and the rear end 183 of the baffle 180 engages with a flange 147b of the housing 140 to form a second seal 102. In this example, the chamber 160 extends continuously from the front flange 147a to the rear flange 147b. Furthermore, the chamber 160 extends continuously circumferentially around the housing 140.

[0086] Both the front end 181 and the rear end 183 of the baffle 180 engage with flanges 147a and 147b, which extend radially outward from the housing 140 to at least partially form a first seal 101 or a second seal 102. The baffle 180 can abut against the flanges 147a and 147b to induce an axial compressive force to form the first seal 101 or the second seal 102. In this example, the baffle 180 is configured as a clamp that induces a compressive force on the flanges 147a and 147b. Furthermore, as shown, the baffle 180 consists of two discrete parts 180a and 180b, which are configured to enhance the sealing performance of the first seal 101 and the second seal 102.

[0087] The front flange 147a of housing 140 defines an inlet 144 to allow fluid (e.g., air discharged from the compressor section of an engine or air from the bypass airflow passage 56) to enter chamber 160. Inlet 144 may be an impingement inlet 144 to provide discrete impingement fluid jets to chamber 160 and to housing 140. The front flange 147a may define a plurality of inlets 144 extending circumferentially around housing 140.

[0088] The rear flange 147b of housing 140 defines an outlet 145 to allow fluid to exit chamber 160. In this example, outlet 145 is positioned to allow fluid to exit chamber 160 at a location (not shown) rear of a first position 150, where housing 140 engages with the rear end of the shroud hanger. As shown, outlet 145 extends through the rear flange 147b of housing 140 at an obtuse angle relative to the surface of housing 140 facing chamber 160. However, in other examples, outlet 145 extends through the rear flange 147b of housing 140 at a perpendicular angle, and in other examples, outlet 145 extends through the rear flange 147b of housing 140 at an acute angle relative to the surface of housing 140 facing chamber 160. Housing 140 may define a plurality of outlets 145 extending circumferentially around housing 140.

[0089] Still referencing Figure 10For example, the front flange 147a of housing 140 may define an inlet 144 instead of an outlet 145 to allow fluid to enter chamber 160, while the rear flange 147b of housing 140 may define an outlet 145 instead of an inlet 144 to allow fluid to exit chamber 160.

[0090] As described above, reducing the thermal capacity mismatch and / or thermal time constant mismatch between the housing 140 and the rotor blade stage 110 allows the gap control assembly 100 to passively control the gap D between the rotor blade stage 110 and the shroud 120. Therefore, adjusting the characteristics of components of the gap control assembly 100 (e.g., flange 147, conductive element 149, or flange recess 148) to reduce the thermal capacity mismatch and / or thermal time constant mismatch may be beneficial. Reducing the thermal capacity mismatch and / or thermal time constant mismatch allows the gap control assembly to passively control the gap D between the rotor blade stage 110 and the shroud 120.

[0091] Furthermore, it should be understood that the features discussed can be incorporated into any example embodiment of the gap control component 100. For example, Figure 3 The flanges 147a, 147d or flanges 147b, 147c can be incorporated into any other example embodiment; Figure 4 The recess 148 can be incorporated into any other example embodiment; Figure 5 The conductive element 149 can be incorporated into any other example embodiment; Figure 6 The two-piece construction can be incorporated into any other example embodiment; Figure 9 The rope seals 103 and 104 can be incorporated into any other example embodiment; such as Figure 10 As shown, the inlet 144 and outlet 145 defined by flanges 147a and 147b can be incorporated into any other example embodiment.

[0092] This written description uses examples to disclose the invention, including the best mode, and also enables any person skilled in the art to practice the invention, including making and using any device or system and performing any combination of methods. The patent scope of the invention is defined by the claims, but may include other examples that would occur to a person skilled in the art. Such other examples are intended to fall within the scope of the claims if they include structural elements that are not indistinguishable from the literal language of the claims, or if they include equivalent structural elements that are not substantially different from the literal language of the claims.

[0093] Further aspects are provided by the following topics:

[0094] 1. A clearance control assembly for a gas turbine engine defining an axial and radial direction and including a first-stage rotor blade and a shroud hanger, the assembly comprising: a housing configured to be positioned outwardly from the first-stage rotor blade in the radial direction when mounted in the gas turbine engine, the housing further configured to engage with the shroud hanger at a first position when mounted in the gas turbine engine; and a baffle positioned outwardly from the housing in the radial direction to define a chamber therebetween, the baffle having a front end and a rear end, wherein the front end of the baffle engages with the housing to form a first seal, and wherein the rear end of the baffle engages with the housing to form a second seal, wherein the baffle, the housing, or both define an inlet to allow fluid to enter the chamber, and the housing defines an outlet to allow the fluid to exit the chamber.

[0095] 2. The component according to any of the preceding clauses, wherein the baffle defines the inlet, wherein the inlet is positioned near the front end of the baffle.

[0096] 3. The component according to any of the preceding clauses, wherein the outlet is located behind the first position and extends from the outer surface of the housing to the inner surface of the housing.

[0097] 4. The component according to any of the preceding clauses, wherein the first seal includes a first rope sealing element positioned between the front end of the baffle and the housing, and wherein the second seal includes a second rope sealing element positioned between the rear end of the baffle and the housing.

[0098] 5. The component according to any of the preceding clauses, wherein the housing includes a flange extending outwardly in the radial direction, and wherein the front end or the rear end of the baffle engages with the flange of the housing to at least partially form the first seal or the second seal.

[0099] 6. The component according to any of the preceding clauses, wherein the protective cover hanger has a rear hook configured to match a corresponding feature of the housing, wherein the first position is the position where the rear hook of the protective cover hanger matches the corresponding feature of the housing.

[0100] 7. The component according to any of the preceding clauses, wherein the chamber extends continuously from the front end of the baffle to the rear end of the baffle.

[0101] 8. The component according to any of the preceding clauses, wherein the housing defines an outer surface along the radial direction, and wherein the component further includes a conductive element positioned on the outer surface of the housing and within the interior.

[0102] 9. The component according to any of the preceding clauses, wherein the housing has a flange extending outward in the radial direction and located between the front end and the rear end of the baffle.

[0103] 10. The component according to any of the preceding clauses, wherein the flange has a recess located near the root end of the flange.

[0104] 11. A gas turbine engine defining an axial and radial direction, the engine comprising: a compressor section; a combustion section downstream of the compressor section; and a turbine section downstream of the combustion section, wherein the turbine section includes a first-stage rotor blade, a shroud hanger, and a clearance control assembly, the clearance control assembly including: a housing positioned outwardly from the first-stage rotor blade along the radial direction, the housing engaging the shroud hanger at a first location; and a baffle positioned outwardly from the housing along the radial direction to form a chamber therebetween, the baffle having a front end and a rear end, wherein the front end of the baffle engages the housing to form a first seal, wherein the rear end of the baffle engages the housing to form a second seal, wherein the baffle or the housing defines an inlet to allow fluid to enter the chamber, and the housing defines an outlet to allow the fluid to exit the chamber.

[0105] 12. The engine according to any of the preceding clauses, wherein the baffle defines the inlet, the inlet being positioned near the front end of the baffle.

[0106] 13. The engine according to any of the preceding clauses, wherein the outlet is located behind the first position and extends from the outer surface of the housing to the inner surface of the housing.

[0107] 14. The engine according to any of the preceding clauses, wherein the first seal includes a first rope sealing element positioned between the front end of the baffle and the housing, and wherein the second seal includes a second rope sealing element positioned between the rear end of the baffle and the housing.

[0108] 15. The engine according to any of the preceding clauses, wherein the front end or the rear end of the baffle engages with a flange extending radially outward from the housing to at least partially form the first seal or the second seal.

[0109] 16. The engine according to any of the preceding clauses, wherein the shroud hanger has a rear hook configured to match a corresponding feature of the housing, the first position being the position where the rear hook of the shroud hanger matches the corresponding feature of the housing.

[0110] 17. The engine according to any of the preceding clauses, wherein the chamber extends continuously from the front end of the baffle to the rear end of the baffle.

[0111] 18. The engine according to any of the preceding clauses further includes a conductive element positioned on the outer surface of the housing and inside the housing.

[0112] 19. The engine according to any of the preceding clauses, wherein the housing has a flange extending radially outward and located between the front end of the baffle and the rear end of the baffle.

[0113] 20. The engine according to any of the preceding clauses, wherein the flange has a recess located near the root end of the flange.

Claims

1. A clearance control assembly for a gas turbine engine, characterized in that, The gas turbine engine defines an axial and radial direction and includes a first-stage rotor blade and a shroud hanger. The assembly includes: A housing defining a first flange and a second flange extending radially outward along the radial direction, wherein the first flange defines a front wall surface and a rear wall surface, and the second flange defines a front wall surface and a rear wall surface, wherein the housing is configured to be positioned outwardly from the first-stage rotor blades along the radial direction when mounted in the gas turbine engine, and the housing is further configured to engage with the shroud hanger at a first location when mounted in the gas turbine engine; and A baffle, wherein the baffle extends from the front wall surface of the first flange to the rear wall surface of the second flange positioned outwardly from the housing, wherein the baffle, the housing, the rear wall surface of the first flange, and the front wall surface of the second flange define a chamber therebetween, the baffle having a front end and a rear end, wherein the front end of the baffle engages with the front wall surface of the first flange to form a first seal, and wherein the rear end of the baffle engages with the rear wall surface of the second flange to form a second seal. The baffle, the housing, or both define an inlet to allow fluid to enter the chamber, and the housing defines an outlet to allow the fluid to leave the chamber.

2. The component according to claim 1, characterized in that, in, The baffle defines the inlet, wherein the inlet is positioned near the front end of the baffle.

3. The component according to claim 1, characterized in that, in, The outlet is located behind the first position and extends through the second flange.

4. The component according to claim 1, characterized in that, in, The first seal includes a first rope sealing element positioned between the front end of the baffle and the first flange, and wherein the second seal includes a second rope sealing element positioned between the rear end of the baffle and the second flange.

5. The component according to claim 1, characterized in that, in, The protective cover hanger has a rear hook configured to match a corresponding feature of the housing, wherein the first position is the position where the rear hook of the protective cover hanger matches the corresponding feature of the housing.

6. The component according to claim 1, characterized in that, in, The chamber extends continuously from the front end of the baffle to the rear end of the baffle.

7. The component according to claim 1, characterized in that, in, The housing defines an outer surface along the radial direction, and wherein the component further includes a conductive element positioned on the outer surface of the housing and within the interior.

8. The component according to claim 1, characterized in that, in, The first flange and the second flange are located between the front end and the rear end of the baffle.

9. The component according to claim 8, characterized in that, in, The first flange and the second flange each have a recess located near the root end of the first flange and the second flange, respectively.

10. A gas turbine engine defining axial and radial directions, characterized in that, The engine includes: Compressor section; A combustion section, the combustion section being located downstream of the compressor section; and A turbine section, located downstream of the combustion section, wherein the turbine section includes first-stage rotor blades, a shroud hanger, and a clearance control assembly, the clearance control assembly including: A housing defining a first flange and a second flange extending radially outward along the radial direction, wherein the first flange defines a front wall surface and a rear wall surface, and the second flange defines a front wall surface and a rear wall surface, wherein the housing is positioned outwardly from the first-stage rotor blade along the radial direction, and the housing engages with the shroud hanger at a first location; and A baffle, wherein the baffle extends from the front wall surface of the first flange to the rear wall surface of the second flange positioned outwardly from the housing, wherein the baffle, the housing, the rear wall surface of the first flange, and the front wall surface of the second flange form a chamber therebetween, the baffle having a front end and a rear end, wherein the front end of the baffle engages with the front wall surface of the first flange to form a first seal, and wherein the rear end of the baffle engages with the rear wall surface of the second flange to form a second seal. The baffle or the housing defines an inlet to allow fluid to enter the chamber, and the housing defines an outlet to allow the fluid to leave the chamber.

11. The engine according to claim 10, characterized in that, in, The baffle defines the entrance, which is positioned near the front end of the baffle.

12. The engine according to claim 10, characterized in that, in, The outlet is located behind the first position and extends through the second flange.

13. The engine according to claim 10, characterized in that, in, The first seal includes a first rope sealing element positioned between the front end of the baffle and the first flange, and wherein the second seal includes a second rope sealing element positioned between the rear end of the baffle and the second flange.

14. The engine according to claim 10, characterized in that, in, The protective cover hanger has a rear hook configured to match a corresponding feature of the housing, and the first position is the position where the rear hook of the protective cover hanger matches the corresponding feature of the housing.

15. The engine according to claim 10, characterized in that, in, The chamber extends continuously from the front end of the baffle to the rear end of the baffle.

16. The engine according to claim 10, characterized in that, It further includes a conductive element positioned on the outer surface of the housing and inside the interior.

17. The engine according to claim 10, characterized in that, in, The first flange and the second flange each have a recess located near the root end of the first flange and the second flange, respectively.

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