Patent Publication Number: US-2023135387-A1

Title: Vane array structure for a hot section of a gas turbine engine

Description:
TECHNICAL FIELD 
     This disclosure relates generally to a gas turbine engine and, more particularly, to a hot section within a gas turbine engine. 
     BACKGROUND INFORMATION 
     A hot section within a gas turbine engine includes various hot section components. These hot section components may be exposed to hot gases (e.g., combustion products) flowing through a core gas path extending through the hot section. This exposure to the hot gases may cause the hot section components to thermally expand or contract at different rates, particularly during transient operating conditions. Such differential thermal expansion or contraction may impart internal stresses on the hot section components. There is a need in the art to reduce thermally induced internal stresses within a hot section of a gas turbine engine. 
     SUMMARY 
     According to an aspect of the present disclosure, an apparatus is provided for a gas turbine engine. This gas turbine engine apparatus includes a first platform, a second platform, a plurality of vanes and a plurality of beams. The first platform extends axially along and circumferentially about an axis. The second platform extends axially along and circumferentially about the axis. The vanes are arranged circumferentially about the axis. Each of the vanes extends radially across a gas path between the first platform and the second platform. The vanes include a first vane movably connected to the first platform. The beams are arranged circumferentially about the axis. The beams are fixedly connected to the first platform and the second platform. The beams include a first beam extending radially through the first vane. 
     According to another aspect of the present disclosure, another apparatus is provided for a gas turbine engine. This gas turbine engine apparatus includes a first platform, a second platform, a plurality of vanes and a plurality of beams. The first platform extends axially along and circumferentially about an axis. The second platform extends axially along and circumferentially about the axis with a gas path formed by and radially between the first platform and the second platform. The vanes are arranged circumferentially about the axis. Each of the vanes extends radially within the gas path and is connected to the first platform and the second platform. The beams structurally tie the first platform to the second platform. Each of the beams projects radially through a respective one of the vanes. 
     According to still another aspect of the present disclosure, another apparatus is provided for a gas turbine engine. This gas turbine engine apparatus includes a vane array structure extending circumferentially about an axis. The vane array structure includes a gas path, a first platform, a second platform, a plurality of vanes and a plurality of beams. The gas path extends axially along the axis through the vane array structure and radially between the first platform and the second platform. A first of the vanes extends radially within the gas path and is attached to the first platform and the second platform. A first of the beams is formed integral with the first platform and the second platform. The first of the beams extends radially through the first of the vanes between the first platform and the second platform. 
     The beams may include a first beam formed integral with the first platform and/or the second platform. 
     The vanes may include a first vane connected to the first platform through a sliding joint. 
     The first beam may be formed integral with the first platform and/or the second platform. 
     The first platform may include a base and a mount projecting radially out from the base into a bore of the first vane. The first vane may be slidably connected to the mount. 
     The first vane may be radially spaced from the base by a gap. 
     The gas turbine engine apparatus may also include a seal element laterally between and sealingly engaged with a sidewall of the first vane and the mount. 
     The first vane may be fixedly connected to the second platform. 
     The first vane may be moveably connected to the second platform. 
     The second platform may include a base and a mount projecting radially out from the base into a bore of the first vane. The first vane may be slidably connected to the mount. 
     The first vane may be radially spaced from the base by a gap. 
     The gas turbine engine apparatus may also include a seal element laterally between and sealingly engaged with a sidewall of the first vane and the mount. 
     The first platform may be configured as an outer platform and may circumscribe the second platform. The second platform may be configured as an inner platform. 
     The first platform may be configured as an inner platform. The second platform may be configured as an outer platform and may circumscribe the first platform. 
     The first vane may include a first vane segment and a second vane segment bonded to the first vane segment. 
     The first vane segment may be bonded to the second vane segment on or about a leading edge of the first vane. The first vane segment may also or alternatively be bonded to the second vane segment on or about a trailing edge of the first vane. 
     The first vane may have a blunt leading edge. 
     The first vane may have a sharp leading edge. 
     The present disclosure may include any one or more of the individual features disclosed above and/or below alone or in any combination thereof. 
     The foregoing features and the operation of the invention will become more apparent in light of the following description and the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a schematic sectional illustration of a portion of a hot section for a gas turbine engine. 
         FIG.  2    is a schematic sectional illustration of a portion of a stationary structure for the hot section. 
         FIG.  3    is a cross-sectional illustration of a portion of the stationary structural at an outer position along a respective vane of the stationary structure. 
         FIG.  4    is a cross-sectional illustration of a portion of the stationary structure at an inner position along the respective vane. 
         FIG.  5    is a cross-sectional illustration of a portion of the stationary structure at an intermediate position along the respective vane. 
         FIG.  6    is a partial sectional illustration of a fixed connection between the respective vane and an outer mount. 
         FIG.  7    is a partial sectional illustration of a movable connection between the respective vane and an inner mount. 
         FIGS.  8 A and  8 B  are partial schematic sectional illustrations of various other stationary structures. 
         FIG.  9    is a partial sectional illustration of a sealed interface between the respective vane and mount. 
         FIG.  10    is a cross-sectional illustration of a segmented vane. 
         FIG.  11    is a cross-sectional illustration of another segmented vane. 
         FIG.  12    is a schematic illustration of a gas turbine engine which may include the hot section. 
     
    
    
     DETAILED DESCRIPTION 
       FIG.  1    illustrates a hot section  20  of a gas turbine engine. The term “hot section” describes herein a section of the gas turbine engine exposed to hot gases; e.g., combustion products. A (e.g., annular) core gas path  22  of the gas turbine engine, for example, extends longitudinally through the hot section  20  of  FIG.  1   . Examples of the hot section  20  include, but are not limited to, a combustor section, a turbine section and an exhaust section. However, for ease of description, the hot section  20  of  FIG.  1    is described below as a turbine section of the gas turbine engine. The hot section  20  of  FIG.  1    includes one or more rotor assemblies  24 A and  24 B (generally referred to as “ 24 ”) and a stationary structure  26 . 
     Each of the rotor assemblies  24  is configured to rotate about a rotational axis  28  of the gas turbine engine, which rotational axis  28  may also be an axial centerline of the gas turbine engine. Each of the rotor assemblies  24 A,  24 B includes a shaft  30 A,  30 B (generally referred to as “ 30 ”) and at least a hot section rotor  32 A,  32 B (generally referred to as “ 32 ”); e.g., a turbine rotor. The shaft  30  extends axially along the rotational axis  28 . The hot section rotor  32  is connected to the shaft  30 . The hot section rotor  32  includes a plurality of hot section rotor blades (e.g., turbine blades) arranged circumferentially around and connected to one or more respective hot section rotor disks. The hot section rotor blades, for example, may be formed integral with or mechanically fastened, welded, brazed, adhered and/or otherwise attached to the respective hot section rotor disk(s). 
     The stationary structure  26  of  FIG.  1    includes a hot section case  34  (e.g., a turbine case) and a hot section structure  36 . The hot section case  34  is configured to house at least a portion or an entirety of the hot section  20  and its components  30 A,  30 B and  36 . The hot section case  34  extends axially along and circumferentially about (e.g., completely around) the rotational axis  28 . 
     The hot section structure  36  is configured to guide the hot gases (e.g., combustion products) received from an upstream section  38 A of the hot section  20  (e.g., a high pressure turbine (HPT) section) to a downstream section  38 B of the hot section  20  (e.g., a low pressure turbine (LPT) section) through the gas path  22 . The hot section structure  36  of  FIG.  1    is also configured to support one or more of the rotor assemblies  24  within the hot section  20  and its hot section case  34 . The hot section structure  36  of  FIG.  1   , for example, is configured as a support structure such as, but not limited to, a turbine frame structure; e.g., a mid-turbine frame. This hot section structure  36  includes a vane array structure  40  and one or more structural supports  42  and  44 ; e.g., struts, frames, etc. 
     The vane array structure  40  of  FIG.  2    includes a plurality of vane array structure members  46  and  48 . The first member  46  may be a structural member of the vane array structure  40  configured to structurally tie the outer structural support  42  and the inner structural support  44  together. The first member  46  of  FIG.  2   , for example, includes an (e.g., tubular) outer platform  50 , an (e.g., tubular) inner platform  52  and a plurality of beams  54 . Each second member  48  may be a non-structural member of the vane array structure  40  configured to house the beams  54  within the gas path  22 . Each second member  48  of  FIG.  2   , for example, is configured as a non-structural vane  56 ; e.g., a fairing, a shell and/or a shield for a respective one of the beams  54 . 
     The outer platform  50  includes an outer platform base  58  (referred to below as an “outer base”) and a plurality of outer platform mounts  60  (referred to below as “outer mounts”). The outer platform  50  and its outer base  58  extend axially along the rotational axis  28  between an upstream end of the outer platform  50  and a downstream end of the outer platform  50 . The outer platform  50  and its outer base  58  extend circumferentially about (e.g., completely around) the rotational axis  28 , thereby providing the outer platform  50  and its outer base  58  each with a full-hoop, tubular body. The outer base  58  extends radially between and to an inner side  62  of the outer base  58  and an outer side  64  of the outer base  58 . The outer base inner side  62  is configured to form an outer peripheral boundary of the gas path  22  through the vane array structure  40 . 
     The outer mounts  60  are distributed circumferentially about the rotational axis  28  in an annular array. Each of the outer mounts  60  is connected to (e.g., formed integral with) the outer base  58  at (e.g., on, adjacent or proximate) its outer base inner side  62 . Each of the outer mounts  60  of  FIG.  2   , for example, projects radially inward from the outer base  58  and its outer base inner side  62  to a (e.g., annular) inner distal edge  66  of the respective outer mount  60 . Referring to  FIG.  3   , each of the outer mounts  60  is axially and circumferentially aligned with a respective one of the beams  54 . Each of the outer mounts  60 , in particular, circumscribes a respective one of the beams  54 . Each outer mount  60  may also be (e.g., completely) laterally spaced / spatially separated from the respective beam  54  by a void; e.g., an annular air gap. 
     The inner platform  52  of  FIG.  2    includes an inner platform base  68  (referred to below as an “inner base”) and a plurality of inner platform mounts  70  (referred to below as “inner mounts”). The inner platform  52  and its inner base  68  extend axially along the rotational axis  28  between an upstream end of the inner platform  52  and a downstream end of the inner platform  52 . The inner platform  52  and its inner base  68  extend circumferentially about (e.g., completely around) the rotational axis  28 , thereby providing the inner platform  52  and its inner base  68  each with a full-hoop, tubular body. The inner base  68  extends radially between and to an inner side  72  of the inner base  68  and an outer side  74  of the inner base  68 . The inner base outer side  74  is configured to form an inner peripheral boundary of the gas path  22  through the vane array structure  40 . 
     The inner mounts  70  are distributed circumferentially about the rotational axis  28  in an annular array. Each of the inner mounts  70  is connected to (e.g., formed integral with) the inner base  68  at (e.g., on, adjacent or proximate) its inner base outer side  74 . Each of the inner mounts  70  of  FIG.  2   , for example, projects radially inward from the inner base  68  and its inner base outer side  74  to a (e.g., annular) outer distal edge  76  of the respective inner mount  70 . Referring to  FIG.  4   , each of the inner mounts  70  is axially and circumferentially aligned with a respective one of the beams  54 . Each of the inner mounts  70 , in particular, circumscribes a respective one of the beams  54 . Each inner mount  70  may also be (e.g., completely) laterally spaced / spatially separated from the respective beam  54  by a void; e.g., an annular air gap. 
     Referring to  FIG.  2   , the beams  54  are distributed circumferentially about the rotational axis  28  in an annular array radially between the outer platform  50  and the inner platform  52 . Each of the beams  54  extends radially between and to the outer platform  50  and its outer base  58  and the inner platform  52  and its inner base  68 . 
     Each of the beams  54  is fixedly connected to the outer platform  50  and the inner platform  52 . Each of the beams  54  of  FIG.  2   , for example, is formed integral with the outer base  58  and the inner base  68 . The outer platform  50 , the inner platform  52  and the beams  54 , for example, may be cast, machined, additively manufactured and/or otherwise formed as a single unitary body; e.g., a monolithic body. The beams  54  of  FIG.  2    may thereby structurally tie the outer platform  50  and its outer base  58  to the inner platform  52  and its inner base  68 . Of course, in other embodiments, one or more of the beams  54  may be formed discrete from the outer platform  50  and/or the inner platform  52  and subsequently mechanically fastened, bonded (e.g., welded or brazed) and/or otherwise fixedly attached to the outer platform  50  and/or the inner platform  52 . 
     Referring to  FIGS.  2 - 5   , each of the beams  54  may be configured as a hollow beam; e.g., a tubular element. Each of the beams  54  of  FIGS.  2 - 5   , for example, has an internal bore  78 . This bore  78  extends longitudinally (e.g., radially relative to the rotational axis  28 ) through the respective beam  54 . Referring to  FIG.  2   , the bore  78  may also extend longitudinally through the outer platform  50  and its outer base  58  and/or the inner platform  52  and its inner base  68 . 
     The vanes  56  are distributed circumferentially about the rotational axis  28  in an annular array radially between the inner platform  52  and the outer platform  50 . Each of the vanes  56  extends radially within the gas path  22  between (to or about) the outer platform  50  and its outer base  58  and the inner platform  52  and its inner base  68 . Each of the vanes  56  may thereby project radially across the gas path  22 . 
     Each of the vanes  56  is connected to the outer platform  50 . Each of the vanes  56  of  FIG.  2   , for example, is mated with a respective one of the outer mounts  60 . This outer mount  60  projects radially inward from the outer base  58  into a bore  80  of the respective vane  56 . Each vane  56  of  FIG.  3    circumscribes the respective outer mount  60 . Each vane  56  of  FIG.  2    laterally engages (e.g., contacts, is abutted against, etc.) an exterior of the respective outer mount  60 . Each vane  56  may also be fixedly connected to the respective outer mount  60 . For example, referring to  FIG.  6   , each vane  56  may be welded, brazed and/or otherwise bonded to the respective outer mount  60  by a bond joint  82 . 
     Each of the vanes  56  of  FIG.  2    is connected to the inner platform  52 . Each of the vanes  56 , for example, is mated with a respective one of the inner mounts  70 . This inner mount  70  projects radially outward from the inner base  68  into the bore  80  of the respective vane  56 . Each vane  56  of  FIG.  4    circumscribes the respective inner mount  70 . Each vane  56  of  FIG.  2    laterally engages (e.g., contacts, is abutted against, etc.) an exterior of the respective inner mount  70 . Each vane  56  may also be movably attached to the respective inner mount  70 . For example, referring to  FIG.  7   , each vane  56  may be slidably connected to the respective inner mount  70  via a slip joint  84  (e.g., a sliding joint, a telescopic joint, etc.) between the elements  56  and  70 . To facilitate the movement between the vane  56  and inner mount  70 , the respective vane  56  may also be spaced radially from the inner base  68  and its inner base outer side  74  by a void  86 ; e.g., an annular air gap. With such an arrangement, the respective vane  56  may thermally expand towards the inner platform  52  without, for example, binding; e.g., bottoming out against the inner base outer side  74 . 
     While the vanes  56  of  FIG.  2    are described above as being fixedly connected to the outer mounts  60  (see also  FIG.  6   ) and movably connected to the inner mounts  70  (see also  FIG.  7   ), the present disclosure is not limited to such an exemplary arrangement. For example, one or more or all of the vanes  56  may alternatively each be fixedly connected to the respective inner mount  70  and movably (e.g., slidably) connected to the respective outer mount  60 . One or more or all of the vanes  56  may still alternatively each be movably (e.g., slidably) connected to both the respective outer mount  60  and the respective inner mount  70 . 
     Each of the beams  54  of  FIG.  2    is mated with a respective one of the vanes  56 . Each of the beams  54 , more particularly, projects radially through a respective one of the vane bores  80  between the outer platform  50  and the inner platform  52 . Each of the vanes  56  of  FIGS.  2 - 5    thereby houses and provides an aerodynamic cover for a respective one of the beams  54 . With this arrangement, the hot gases flowing through the gas path  22  within the vane array structure  40  are radially bounded and guided by the outer platform  50  and the inner platform  52  and flow around (e.g., to either side of) each vane  56 ; see also  FIGS.  3 - 5   . Each of the vanes  56  of  FIGS.  2 - 5    also forms a thermal shield for a respective one of the beams  54  with a thermal break laterally between the respective beam  54  and vane  56 . For example, referring to  FIG.  5   , a void (e.g., an annular air gap) extends laterally between the respective beam  54  and vane  56 . The void of  FIG.  5    also circumscribes the respective beam  54 . 
     Referring to  FIG.  1   , the outer structural support  42  is connected to the outer platform  50  and the hot section case  34 . The outer structural support  42  of  FIG.  1   , for example, projects radially out from the outer base  58  to the hot section case  34 . The outer structural support  42  may thereby structurally tie the vane array structure  40  to the hot section case  34 . 
     The inner structural support  44  is connected to the inner platform  52 , and rotatably supports one or more of the rotor assemblies  24 . The inner structural support  44  of  FIG.  1   , for example, includes (or is connected to) a bearing support frame  88 , and projects radially in from the inner base  68  to the bearing support frame  88 . Each shaft  30 A,  30 B is rotatably supported by a respective bearing  90 A,  90 B (generally referred to as “ 90 ”) (e.g., a roller element bearing), which bearing  90  is mounted to and supported by the bearing support frame  88 . The inner structural support  44  may thereby structurally tie the rotor assemblies  24  to the vane array structure  40 . 
     During operation, the vane array structure  40  of  FIG.  2    and its components  50 ,  52  and  56  are exposed to (e.g., are in contact with) the hot gases (e.g., combustion products) flowing through the gas path  22 . This hot gas exposure may create a relatively large thermal gradient across the vane array structure  40 , particularly during transient operating conditions. For example, a thickness  92  of a sidewall  94  of each vane  56  may be thinner than a thickness  96  of the outer base  58  and/or a thickness  98  of the inner base  68 . Furthermore, while the hot gases flow along the outer platform  50 , the inner platform  52  and the vane sidewalls  94 , the hot gases also impinge against a leading edge  100  of each vane  56 . Each vane  56  and its vane sidewall  94  may therefore heat up (or cool down) fastener than the outer platform  50  and the inner platform  52 . The vane array structure  40  may accommodate this thermal gradient since each vane  56  / second member  48  may thermally expand (or contract) radially independent of the first member  46  and its respective beam  54  via the moveable connection (see also  FIG.  7   ) between the respective vane  56  and mount  70  (or the mount  60 ). Such relative movement between the first member  46  and the second members  48  may reduce internal thermally induced stresses within the vane array structure  40  as compared to another arrangement where each vane  802  is fixedly connected to both outer and inner platforms  804  and  806 ; e.g., see  FIG.  8 A . The vane array structure  40  of  FIG.  2    may also have a reduced size, complexity and/or mass as compared to a discrete fixed beam arrangement  808  with a beam  810  that is discrete from (e.g., and not structurally tied to) the elements  802 ,  804  and  806 ; e.g., see  FIG.  8 B . 
     In some embodiments, referring to  FIG.  9   , one or more or all of the vanes  56  may each engage a respective one of the mounts  60 ,  70  through a seal element  102 . This seal element  102  may be configured as or otherwise include a rope seal; e.g., an incobraid rope seal with a core constructed from ceramic fiber wrapped with braided wire metal (e.g., Inconel) material. The seal element  102  may be seated in a notch or groove in the respective mount  60 ,  70 , and laterally engage (e.g., press against, contact, etc.) an interior surface of the respective vane  56 . The seal element  102  may thereby provide a sealed interface between the respective vane  56  and the platform  50 ,  52 . The seal element  102  may also facilitate the movable (e.g., slidable) connection between the respective vane  56  and the platform  50 ,  52 . The seal element  102  may also damp vibrations between the elements  56  and  60 ,  70  as well as hold the respective vane  56  vertically in place via a compression fit. Such a connection may be used between the respective vane  56  and the outer mount  60  and/or the respective vane  56  and the inner mount  70 . 
     In some embodiments, referring to  FIG.  10   , one or more or all of the vanes  56  may each be configured with a blunt (e.g., bulbous, curved, etc.) leading edge  100  and a sharp (e.g., pointed, tapered, etc.) trailing edge  104 . In other embodiments, referring to  FIG.  11   , one or more or all of the vanes  56  may each be configured with a sharp leading edge  100  and the sharp trailing edge  104 . 
     In some embodiments, referring to  FIGS.  10  and  11   , one or more or all of the vanes  56  may each include plurality of (e.g., sheet metal) vane segments  106 A and  106 B (generally referred to as “ 106 ”); e.g., vane halves, vane sides, etc. Each of these vane segments  106  may extend along an entire radial span of the respective vane  56 . The first vane segment  106 A may meet the second vane segment  106 B at a first interface  108 , which first interface  108  may be located at the leading edge  100 . The first vane segment  106 A is connected (e.g., welded, brazed and/or otherwise bonded) to the second vane segment  106 B along the first interface  108 . The first vane segment  106 A may also or alternatively meet the second vane segment  106 B at a second interface  110 , which second interface  110  may be located at the trailing edge  104 . The first vane segment  106 A is connected (e.g., welded, brazed and/or otherwise bonded) to the second vane segment  106 B along the second interface  110 . 
       FIG.  12    is a schematic illustration of a gas turbine engine  112  which may include the hot section  20 . This gas turbine engine  112  includes a compressor section  114 , a combustor section  115 , a turbine section  116  and an exhaust section  117 . The gas path  22  extends longitudinally sequentially through the compressor section  114 , the combustor section  115 , the turbine section  116  and the exhaust section  117  from an upstream engine inlet  118  to a downstream engine exhaust  120 . During operation, air enters the gas turbine engine  112  and the gas path  22  through the engine inlet  118 . This air is compressed by the compressor section  114  and directed into the combustor section  115 . Within the combustor section  115 , the compressed air is mixed with fuel and ignited to produce the hot gases; e.g., combustion products. These hot gases are directed out of the combustor section  115  and into the turbine section  116  to drive compression within the compressor section  114 . The hot gases then flow through the exhaust section  117  and are exhausted form the gas turbine engine  112  through the engine exhaust  120 . 
     The gas turbine engine  112  may be configured as a geared gas turbine engine, where a gear train connects one or more shafts to one or more rotors. The gas turbine engine  112  may alternatively be configured as a direct drive gas turbine engine configured without a gear train. The gas turbine engine  112  may be configured with a single spool, with two spools, or with more than two spools. The gas turbine engine  112  may be configured as a turbofan engine, a turbojet engine, a turboprop engine, a turboshaft engine, a propfan engine, a pusher fan engine or any other type of gas turbine engine. The gas turbine engine  112  may alternative be configured as an auxiliary power unit (APU) or an industrial gas turbine engine. The present disclosure therefore is not limited to any particular types or configurations of gas turbine engines. 
     While various embodiments of the present disclosure have been described, it will be apparent to those of ordinary skill in the art that many more embodiments and implementations are possible within the scope of the disclosure. For example, the present disclosure as described herein includes several aspects and embodiments that include particular features. Although these features may be described individually, it is within the scope of the present disclosure that some or all of these features may be combined with any one of the aspects and remain within the scope of the disclosure. Accordingly, the present disclosure is not to be restricted except in light of the attached claims and their equivalents.