Patent Description:
The present invention relates to an apparatus for a gas turbine engine.

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. <CIT>, <CIT> and <CIT> disclose arrangements of the prior art.

According to an aspect of the invention, 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. The beams include a first beam formed integral with the first platform and the second platform.

The following optional features may be applied to the above aspect.

The first platform may include a base (e.g., a first base or a first platform base) and a mount (e.g., a first mount or a first platform mount) projecting radially out from the base into a bore of the first vane. The first vane may be slidably connected to the mount (e.g., the first mount or the first platform mount).

The first vane may be radially spaced from the base (e.g., the first base or the first platform base) by a gap (e.g., a first gap).

The gas turbine engine apparatus may also include a seal element (e.g., a first seal element) laterally between and sealingly engaged with a sidewall of the first vane and the mount (e.g., the first 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 (e.g., a second base or a second platform base) and a mount (e.g., a second mount or a second platform mount) projecting radially out from the base into a bore of the first vane. The first vane may be slidably connected to the mount (e.g., the second mount or the second platform mount).

The first vane may be radially spaced from the base (e.g., the second base or the second platform base) by a gap (e.g., a second gap).

The gas turbine engine apparatus may also include a seal element (e.g., a second seal element) laterally between and sealingly engaged with a sidewall of the first vane and the mount (e.g. the second 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.

<FIG> illustrates a hot section <NUM> 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 <NUM> of the gas turbine engine, for example, extends longitudinally through the hot section <NUM> of <FIG>. Examples of the hot section <NUM> include, but are not limited to, a combustor section, a turbine section and an exhaust section. However, for ease of description, the hot section <NUM> of <FIG> is described below as a turbine section of the gas turbine engine. The hot section <NUM> of <FIG> includes one or more rotor assemblies 24A and 24B (generally referred to as "<NUM>") and a stationary structure <NUM>.

Each of the rotor assemblies <NUM> is configured to rotate about a rotational axis <NUM> of the gas turbine engine, which rotational axis <NUM> may also be an axial centerline of the gas turbine engine. Each of the rotor assemblies 24A, 24B includes a shaft 30A, 30B (generally referred to as "<NUM>") and at least a hot section rotor 32A, 32B (generally referred to as "<NUM>"); e.g., a turbine rotor. The shaft <NUM> extends axially along the rotational axis <NUM>. The hot section rotor <NUM> is connected to the shaft <NUM>. The hot section rotor <NUM> 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 <NUM> of <FIG> includes a hot section case <NUM> (e.g., a turbine case) and a hot section structure <NUM>. The hot section case <NUM> is configured to house at least a portion or an entirety of the hot section <NUM> and its components 30A, 30B and <NUM>. The hot section case <NUM> extends axially along and circumferentially about (e.g., completely around) the rotational axis <NUM>.

The hot section structure <NUM> is configured to guide the hot gases (e.g., combustion products) received from an upstream section 38A of the hot section <NUM> (e.g., a high pressure turbine (HPT) section) to a downstream section 38B of the hot section <NUM> (e.g., a low pressure turbine (LPT) section) through the gas path <NUM>. The hot section structure <NUM> of <FIG> is also configured to support one or more of the rotor assemblies <NUM> within the hot section <NUM> and its hot section case <NUM>. The hot section structure <NUM> of <FIG>, 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 <NUM> includes a vane array structure <NUM> and one or more structural supports <NUM> and <NUM>; e.g., struts, frames, etc..

The vane array structure <NUM> of <FIG> includes a plurality of vane array structure members <NUM> and <NUM>. The first member <NUM> may be a structural member of the vane array structure <NUM> configured to structurally tie the outer structural support <NUM> and the inner structural support <NUM> together. The first member <NUM> of <FIG>, for example, includes an (e.g., tubular) outer platform <NUM>, an (e.g., tubular) inner platform <NUM> and a plurality of beams <NUM>. Each second member <NUM> may be a non-structural member of the vane array structure <NUM> configured to house the beams <NUM> within the gas path <NUM>. Each second member <NUM> of <FIG>, for example, is configured as a non-structural vane <NUM>; e.g., a fairing, a shell and/or a shield for a respective one of the beams <NUM>.

The outer platform <NUM> includes an outer platform base <NUM> (referred to below as an "outer base") and a plurality of outer platform mounts <NUM> (referred to below as "outer mounts"). The outer platform <NUM> and its outer base <NUM> extend axially along the rotational axis <NUM> between an upstream end of the outer platform <NUM> and a downstream end of the outer platform <NUM>. The outer platform <NUM> and its outer base <NUM> extend circumferentially about (e.g., completely around) the rotational axis <NUM>, thereby providing the outer platform <NUM> and its outer base <NUM> each with a full-hoop, tubular body. The outer base <NUM> extends radially between and to an inner side <NUM> of the outer base <NUM> and an outer side <NUM> of the outer base <NUM>. The outer base inner side <NUM> is configured to form an outer peripheral boundary of the gas path <NUM> through the vane array structure <NUM>.

The outer mounts <NUM> are distributed circumferentially about the rotational axis <NUM> in an annular array. Each of the outer mounts <NUM> is connected to (e.g., formed integral with) the outer base <NUM> at (e.g., on, adjacent or proximate) its outer base inner side <NUM>. Each of the outer mounts <NUM> of <FIG>, for example, projects radially inward from the outer base <NUM> and its outer base inner side <NUM> to a (e.g., annular) inner distal edge <NUM> of the respective outer mount <NUM>. Referring to <FIG>, each of the outer mounts <NUM> is axially and circumferentially aligned with a respective one of the beams <NUM>. Each of the outer mounts <NUM>, in particular, circumscribes a respective one of the beams <NUM>. Each outer mount <NUM> may also be (e.g., completely) laterally spaced / spatially separated from the respective beam <NUM> by a void; e.g., an annular air gap.

The inner platform <NUM> of <FIG> includes an inner platform base <NUM> (referred to below as an "inner base") and a plurality of inner platform mounts <NUM> (referred to below as "inner mounts"). The inner platform <NUM> and its inner base <NUM> extend axially along the rotational axis <NUM> between an upstream end of the inner platform <NUM> and a downstream end of the inner platform <NUM>. The inner platform <NUM> and its inner base <NUM> extend circumferentially about (e.g., completely around) the rotational axis <NUM>, thereby providing the inner platform <NUM> and its inner base <NUM> each with a full-hoop, tubular body. The inner base <NUM> extends radially between and to an inner side <NUM> of the inner base <NUM> and an outer side <NUM> of the inner base <NUM>. The inner base outer side <NUM> is configured to form an inner peripheral boundary of the gas path <NUM> through the vane array structure <NUM>.

The inner mounts <NUM> are distributed circumferentially about the rotational axis <NUM> in an annular array. Each of the inner mounts <NUM> is connected to (e.g., formed integral with) the inner base <NUM> at (e.g., on, adjacent or proximate) its inner base outer side <NUM>. Each of the inner mounts <NUM> of <FIG>, for example, projects radially inward from the inner base <NUM> and its inner base outer side <NUM> to a (e.g., annular) outer distal edge <NUM> of the respective inner mount <NUM>. Referring to <FIG>, each of the inner mounts <NUM> is axially and circumferentially aligned with a respective one of the beams <NUM>. Each of the inner mounts <NUM>, in particular, circumscribes a respective one of the beams <NUM>. Each inner mount <NUM> may also be (e.g., completely) laterally spaced / spatially separated from the respective beam <NUM> by a void; e.g., an annular air gap.

Referring to <FIG>, the beams <NUM> are distributed circumferentially about the rotational axis <NUM> in an annular array radially between the outer platform <NUM> and the inner platform <NUM>. Each of the beams <NUM> extends radially between and to the outer platform <NUM> and its outer base <NUM> and the inner platform <NUM> and its inner base <NUM>.

Each of the beams <NUM> is fixedly connected to the outer platform <NUM> and the inner platform <NUM>. Each of the beams <NUM> of <FIG>, for example, is formed integral with the outer base <NUM> and the inner base <NUM>. The outer platform <NUM>, the inner platform <NUM> and the beams <NUM>, for example, may be cast, machined, additively manufactured and/or otherwise formed as a single unitary body; e.g., a monolithic body. The beams <NUM> of <FIG> may thereby structurally tie the outer platform <NUM> and its outer base <NUM> to the inner platform <NUM> and its inner base <NUM>.

Referring to <FIG>, each of the beams <NUM> may be configured as a hollow beam; e.g., a tubular element. Each of the beams <NUM> of <FIG>, for example, has an internal bore <NUM>. This bore <NUM> extends longitudinally (e.g., radially relative to the rotational axis <NUM>) through the respective beam <NUM>. Referring to <FIG>, the bore <NUM> may also extend longitudinally through the outer platform <NUM> and its outer base <NUM> and/or the inner platform <NUM> and its inner base <NUM>.

The vanes <NUM> are distributed circumferentially about the rotational axis <NUM> in an annular array radially between the inner platform <NUM> and the outer platform <NUM>. Each of the vanes <NUM> extends radially within the gas path <NUM> between (to or about) the outer platform <NUM> and its outer base <NUM> and the inner platform <NUM> and its inner base <NUM>. Each of the vanes <NUM> may thereby project radially across the gas path <NUM>.

Each of the vanes <NUM> is connected to the outer platform <NUM>. Each of the vanes <NUM> of <FIG>, for example, is mated with a respective one of the outer mounts <NUM>. This outer mount <NUM> projects radially inward from the outer base <NUM> into a bore <NUM> of the respective vane <NUM>. Each vane <NUM> of <FIG> circumscribes the respective outer mount <NUM>. Each vane <NUM> of <FIG> laterally engages (e.g., contacts, is abutted against, etc.) an exterior of the respective outer mount <NUM>. Each vane <NUM> may also be fixedly connected to the respective outer mount <NUM>. For example, referring to <FIG>, each vane <NUM> may be welded, brazed and/or otherwise bonded to the respective outer mount <NUM> by a bond joint <NUM>.

Each of the vanes <NUM> of <FIG> is connected to the inner platform <NUM>. Each of the vanes <NUM>, for example, is mated with a respective one of the inner mounts <NUM>. This inner mount <NUM> projects radially outward from the inner base <NUM> into the bore <NUM> of the respective vane <NUM>. Each vane <NUM> of <FIG> circumscribes the respective inner mount <NUM>. Each vane <NUM> of <FIG> laterally engages (e.g., contacts, is abutted against, etc.) an exterior of the respective inner mount <NUM>. Each vane <NUM> may also be movably attached to the respective inner mount <NUM>. For example, referring to <FIG>, each vane <NUM> may be slidably connected to the respective inner mount <NUM> via a slip joint <NUM> (e.g., a sliding joint, a telescopic joint, etc.) between the elements <NUM> and <NUM>. To facilitate the movement between the vane <NUM> and inner mount <NUM>, the respective vane <NUM> may also be spaced radially from the inner base <NUM> and its inner base outer side <NUM> by a void <NUM>; e.g., an annular air gap. With such an arrangement, the respective vane <NUM> may thermally expand towards the inner platform <NUM> without, for example, binding; e.g., bottoming out against the inner base outer side <NUM>.

While the vanes <NUM> of <FIG> are described above as being fixedly connected to the outer mounts <NUM> (see also <FIG>) and movably connected to the inner mounts <NUM> (see also <FIG>), the present disclosure is not limited to such an exemplary arrangement. For example, one or more or all of the vanes <NUM> may alternatively each be fixedly connected to the respective inner mount <NUM> and movably (e.g., slidably) connected to the respective outer mount <NUM>. One or more or all of the vanes <NUM> may still alternatively each be movably (e.g., slidably) connected to both the respective outer mount <NUM> and the respective inner mount <NUM>.

Each of the beams <NUM> of <FIG> is mated with a respective one of the vanes <NUM>. Each of the beams <NUM>, more particularly, projects radially through a respective one of the vane bores <NUM> between the outer platform <NUM> and the inner platform <NUM>. Each of the vanes <NUM> of <FIG> thereby houses and provides an aerodynamic cover for a respective one of the beams <NUM>. With this arrangement, the hot gases flowing through the gas path <NUM> within the vane array structure <NUM> are radially bounded and guided by the outer platform <NUM> and the inner platform <NUM> and flow around (e.g., to either side of) each vane <NUM>; see also <FIG>. Each of the vanes <NUM> of <FIG> also forms a thermal shield for a respective one of the beams <NUM> with a thermal break laterally between the respective beam <NUM> and vane <NUM>. For example, referring to <FIG>, a void (e.g., an annular air gap) extends laterally between the respective beam <NUM> and vane <NUM>. The void of <FIG> also circumscribes the respective beam <NUM>.

Referring to <FIG>, the outer structural support <NUM> is connected to the outer platform <NUM> and the hot section case <NUM>. The outer structural support <NUM> of <FIG>, for example, projects radially out from the outer base <NUM> to the hot section case <NUM>. The outer structural support <NUM> may thereby structurally tie the vane array structure <NUM> to the hot section case <NUM>.

The inner structural support <NUM> is connected to the inner platform <NUM>, and rotatably supports one or more of the rotor assemblies <NUM>. The inner structural support <NUM> of <FIG>, for example, includes (or is connected to) a bearing support frame <NUM>, and projects radially in from the inner base <NUM> to the bearing support frame <NUM>. Each shaft 30A, 30B is rotatably supported by a respective bearing 90A, 90B (generally referred to as "<NUM>") (e.g., a roller element bearing), which bearing <NUM> is mounted to and supported by the bearing support frame <NUM>. The inner structural support <NUM> may thereby structurally tie the rotor assemblies <NUM> to the vane array structure <NUM>.

During operation, the vane array structure <NUM> of <FIG> and its components <NUM>, <NUM> and <NUM> are exposed to (e.g., are in contact with) the hot gases (e.g., combustion products) flowing through the gas path <NUM>. This hot gas exposure may create a relatively large thermal gradient across the vane array structure <NUM>, particularly during transient operating conditions. For example, a thickness <NUM> of a sidewall <NUM> of each vane <NUM> may be thinner than a thickness <NUM> of the outer base <NUM> and/or a thickness <NUM> of the inner base <NUM>. Furthermore, while the hot gases flow along the outer platform <NUM>, the inner platform <NUM> and the vane sidewalls <NUM>, the hot gases also impinge against a leading edge <NUM> of each vane <NUM>. Each vane <NUM> and its vane sidewall <NUM> may therefore heat up (or cool down) faster than the outer platform <NUM> and the inner platform <NUM>. The vane array structure <NUM> may accommodate this thermal gradient since each vane <NUM> / second member <NUM> may thermally expand (or contract) radially independent of the first member <NUM> and its respective beam <NUM> via the moveable connection (see also <FIG>) between the respective vane <NUM> and mount <NUM> (or the mount <NUM>). Such relative movement between the first member <NUM> and the second members <NUM> may reduce internal thermally induced stresses within the vane array structure <NUM> as compared to another arrangement where each vane <NUM> is fixedly connected to both outer and inner platforms <NUM> and <NUM>; e.g., see <FIG>. The vane array structure <NUM> of <FIG> may also have a reduced size, complexity and/or mass as compared to a discrete fixed beam arrangement <NUM> with a beam <NUM> that is discrete from (e.g., and not structurally tied to) the elements <NUM>, <NUM> and <NUM>; e.g., see <FIG>.

In some embodiments, referring to <FIG>, one or more or all of the vanes <NUM> may each engage a respective one of the mounts <NUM>, <NUM> through a seal element <NUM>. This seal element <NUM> 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 <NUM> may be seated in a notch or groove in the respective mount <NUM>, <NUM>, and laterally engage (e.g., press against, contact, etc.) an interior surface of the respective vane <NUM>. The seal element <NUM> may thereby provide a sealed interface between the respective vane <NUM> and the platform <NUM>, <NUM>. The seal element <NUM> may also facilitate the movable (e.g., slidable) connection between the respective vane <NUM> and the platform <NUM>, <NUM>. The seal element <NUM> may also damp vibrations between the elements <NUM> and <NUM>, <NUM> as well as hold the respective vane <NUM> vertically in place via a compression fit. Such a connection may be used between the respective vane <NUM> and the outer mount <NUM> and/or the respective vane <NUM> and the inner mount <NUM>.

In some embodiments, referring to <FIG>, one or more or all of the vanes <NUM> may each be configured with a blunt (e.g., bulbous, curved, etc.) leading edge <NUM> and a sharp (e.g., pointed, tapered, etc.) trailing edge <NUM>. In other embodiments, referring to <FIG>, one or more or all of the vanes <NUM> may each be configured with a sharp leading edge <NUM> and the sharp trailing edge <NUM>.

In some embodiments, referring to <FIG>, one or more or all of the vanes <NUM> may each include plurality of (e.g., sheet metal) vane segments 106A and 106B (generally referred to as "<NUM>"); e.g., vane halves, vane sides, etc. Each of these vane segments <NUM> may extend along an entire radial span of the respective vane <NUM>. The first vane segment 106A may meet the second vane segment 106B at a first interface <NUM>, which first interface <NUM> may be located at the leading edge <NUM>. The first vane segment 106A is connected (e.g., welded, brazed and/or otherwise bonded) to the second vane segment 106B along the first interface <NUM>. The first vane segment 106A may also or alternatively meet the second vane segment 106B at a second interface <NUM>, which second interface <NUM> may be located at the trailing edge <NUM>. The first vane segment 106A is connected (e.g., welded, brazed and/or otherwise bonded) to the second vane segment 106B along the second interface <NUM>.

<FIG> is a schematic illustration of a gas turbine engine <NUM> which may include the hot section <NUM>. This gas turbine engine <NUM> includes a compressor section <NUM>, a combustor section <NUM>, a turbine section <NUM> and an exhaust section <NUM>. The gas path <NUM> extends longitudinally sequentially through the compressor section <NUM>, the combustor section <NUM>, the turbine section <NUM> and the exhaust section <NUM> from an upstream engine inlet <NUM> to a downstream engine exhaust <NUM>. During operation, air enters the gas turbine engine <NUM> and the gas path <NUM> through the engine inlet <NUM>. This air is compressed by the compressor section <NUM> and directed into the combustor section <NUM>. Within the combustor section <NUM>, 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 <NUM> and into the turbine section <NUM> to drive compression within the compressor section <NUM>. The hot gases then flow through the exhaust section <NUM> and are exhausted form the gas turbine engine <NUM> through the engine exhaust <NUM>.

The gas turbine engine <NUM> 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 <NUM> may alternatively be configured as a direct drive gas turbine engine configured without a gear train. The gas turbine engine <NUM> may be configured with a single spool, with two spools, or with more than two spools. The gas turbine engine <NUM> 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 <NUM> 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.

Claim 1:
An apparatus for a gas turbine engine, comprising:
a first platform (<NUM>, <NUM>) extending axially along and circumferentially about an axis (<NUM>);
a second platform (<NUM>, <NUM>) extending axially along and circumferentially about the axis (<NUM>);
a plurality of vanes (<NUM>) arranged circumferentially about the axis (<NUM>), each of the plurality of vanes (<NUM>) extending radially across a gas path (<NUM>) between the first platform (<NUM>, <NUM>) and the second platform (<NUM>, <NUM>), and the plurality of vanes (<NUM>) comprising a first vane (<NUM>) movably connected to the first platform (<NUM>, <NUM>); and
a plurality of beams (<NUM>) arranged circumferentially about the axis (<NUM>), the plurality of beams (<NUM>) fixedly connected to the first platform (<NUM>, <NUM>) and the second platform (<NUM>, <NUM>), and the plurality of beams (<NUM>) comprising a first beam (<NUM>) extending radially through the first vane (<NUM>);
characterised in that the first beam (<NUM>) is formed integral with the first platform (<NUM>, <NUM>) and the second platform (<NUM>, <NUM>).