ROTOR BLADE AND METHOD FOR FORMING A ROTOR BLADE

An apparatus is provided for a rotor assembly with a rotational axis. This apparatus includes a rotor blade including an airfoil, a neck and an attachment. The neck radially connects the airfoil and the attachment. The attachment extends axially between an attachment first axial side and an attachment second axial side. A first end portion of the attachment projects axially out from the neck to the attachment first axial side. A second end portion of the attachment projects axially out from the neck to the attachment second axial side.

BACKGROUND OF THE DISCLOSURE

1. Technical Field

This disclosure relates generally to rotational equipment and, more particularly, to rotor blades and associated rotor assemblies.

2. Background Information

Gas turbine engine designers are continually being challenged to provide gas turbine engines with improved performance at reduced weights. One design metric being pushed to provide improved performance is increasing turbine rotational speed. As the turbine rotational speed is increased, however, rotor disk bores also increase in size in order to accommodate increasing centrifugal loading. This can result in bore widths that are so large that heat treating the center of a bore may become challenging. Rotor disk sizing may also be impacted by rim pull which includes the mass of airfoils and interrupted (circumferentially discontinuous) features created by axially or angled airfoil attachment features.

Current turbine design standard includes separate airfoils that are mechanically attached to a disk using single or multiple tooth attachments; e.g., fir tree attachments. Provision of these attachments result in a live rim (full hoop or circumferentially continuous rim) that transfers radial loads from the airfoils as well as segmented portions of the disk between airfoil attachments. In addition, cover plates are typically employed to reduce leakage through attachments from one side of the disk to the other.

There is a need in the art for improved rotor blades and rotor assemblies with reduced weights and/or with improved cooling schemes. This includes rotor blades made using high temperature composites such as ceramic matrix composite (CMC) materials. It should be recognized that designing for such composite airfoils may require new rotor architectures to accommodate and exploit the unique capabilities and limitations of composite materials.

SUMMARY OF THE DISCLOSURE

According to an aspect of the present disclosure, an apparatus is provided for a rotor assembly with a rotational axis. This apparatus includes a rotor blade including an airfoil, a platform, a neck and an attachment. The neck radially connects the platform and the attachment. The attachment extends axially between an attachment first axial side and an attachment second axial side. A first end portion of the attachment projects axially out from the neck to the attachment first axial side. A second end portion of the attachment projects axially out from the neck to the attachment second axial side.

According to another aspect of the present disclosure, another apparatus is provided for a rotor assembly with a rotational axis. This apparatus includes a rotor blade including an airfoil, a neck and an attachment. The neck radially connects the airfoil and the attachment. The attachment extends axially between an attachment first axial side and an attachment second axial side. A first end portion of the attachment projects axially out from the neck to the attachment first axial side. A second end portion of the attachment projects axially out from the neck to the attachment second axial side.

According to another aspect of the present disclosure, a manufacturing method is provided that includes a step of forming a rotor blade for a rotor assembly with a rotational axis. This rotor blade includes an airfoil, a neck and an attachment. The neck radially connects the airfoil and the attachment. The attachment extends axially between an attachment first axial side and an attachment second axial side. A first end portion of the attachment projects axially out from the neck to the attachment first axial side. A second end portion of the attachment projects axially out from the neck to the attachment second axial side.

According to still another aspect of the present disclosure, another manufacturing method is provided that includes a step of forming a rotor blade for a rotor assembly with a rotational axis. The forming includes: (A) providing an attachment preform to form a base of an attachment of the rotor blade; (B) wrapping a first sheet of material about the attachment preform to form a first portion of the attachment and a portion of an airfoil of the rotor blade; and (C) wrapping a second sheet of material about the attachment preform and over the first sheet of material to form a second portion of the attachment and a portion of a platform of the rotor blade.

The first end portion of the attachment may be configured as a first cantilevered projection. The second end portion of the attachment may also or alternatively be configured as a second cantilevered projection.

The rotor blade may also include a platform. A first gap, located axially adjacent the neck, may extend radially between the first end portion of the attachment and the platform. In addition or alternatively, a second gap, located axially adjacent the neck, may extend radially between the second end portion of the attachment and the platform.

The rotor blade may be configured from or otherwise include ceramic.

The rotor blade may be configured from or otherwise include metal.

The rotor blade may be configured from or otherwise include intermetallic material.

The attachment may have a flared cross-sectional geometry.

The apparatus may also include an attachment preform and a sheet of material. The attachment preform may be configured to form a base of the attachment. The sheet of material may be wrapped about the attachment preform to form a portion of the attachment and a portion of the airfoil.

The attachment preform may have a triangular cross-sectional geometry.

The attachment preform may have a tubular attachment preform.

The attachment preform may include an outer shell surrounding filler material.

Opposing distal ends of the sheet of material may be located at a tip of the airfoil.

The apparatus may also include a second sheet of material wrapped about the attachment preform and over the sheet of material to form a second portion of the attachment and a portion of a platform of the rotor blade.

Opposing distal ends of the second sheet of material may be located at opposing lateral ends of the platform.

The apparatus may also include a third sheet of material covering the second sheet of material to form a third portion of the attachment, a portion of the neck and a second portion of the platform.

Opposing distal ends of the third sheet of material may be located on a common lateral side of the rotor blade.

The rotor blade may be configured with an internal cooling passage.

The forming may include steps of: providing an attachment preform to form a base of the attachment; and wrapping a sheet of material about the attachment preform to form a portion of the attachment and a portion of the airfoil.

The forming may also include a step of wrapping a second sheet of material about the attachment preform and over the sheet of material to form a second portion of the attachment and a portion of the platform.

The forming may also include a step of covering the second sheet of material with a third sheet of material to form a third portion of the attachment, a portion of the neck and a second portion of the platform.

The forming may also include a step of layering a third sheet of material over the second sheet of material to form a third portion of the attachment, a portion of a neck of the rotor blade and a second portion of the platform.

The attachment may extend axially between an attachment first axial side and an attachment second axial side. An axial first end portion of the attachment may project axially out from a neck of the rotor blade to the attachment first axial side. An axial second end portion of the attachment may project axially out from the neck to the attachment second axial side.

DETAILED DESCRIPTION

FIG. 1illustrates a bladed rotor assembly100for rotational equipment with an axial centerline102, which centerline102may be or may be coaxial with an axis of rotation (e.g., a rotational axis) of the rotor assembly100. An example of such rotational equipment is a gas turbine engine for an aircraft propulsion system, an exemplary embodiment of which is described below in further detail with respect toFIG. 36. However, the rotor assembly100of the present disclosure is not limited to such an aircraft application nor a gas turbine engine application. The rotor assembly100, for example, may alternatively be configured with rotational equipment such as an industrial gas turbine engine, a wind turbine, a water turbine or any other apparatus which includes a bladed rotor.

The rotor assembly100ofFIG. 1includes a plurality of rotor blades104and a rotor disk assembly106. Referring toFIGS. 2 and 3, each of the rotor blades104may be configured as a rotor blade singlet; e.g., a rotor blade that only includes a single airfoil. The present disclosure, however, is not limited to such an exemplary rotor blade configuration. In other embodiments, for example, one or more or each of the rotor blades104may alternatively be configured as a rotor blade doublet with a pair of airfoils.

Referring still toFIGS. 2 and 3, each rotor blade104includes a rotor blade mount108and a rotor blade airfoil110. The rotor blade mount108ofFIGS. 2 and 3includes a mount platform112, a mount neck114and a mount attachment116.

The mount platform112is configured to form a portion of an inner peripheral boarder of a gas path118(e.g., a core gas path) that extends axially along the axial centerline102across the rotor assembly100; e.g., a gas path into which the airfoils110radially extend. The mount platform112, for example, extends radially relative to the axial centerline102between a platform inner end120and a platform outer end122. The platform outer end122carriers a gas path surface124, which forms the respective inner peripheral boarder portion of the gas path118. As best seen inFIG. 3, the gas path surface124extends axially between a platform first (e.g., forward and/or upstream) side126and a platform second (e.g., aft and/or downstream) side128. As best seen inFIG. 2, the gas path surface124extends laterally (e.g., circumferentially or tangentially) between opposing platform lateral sides130and132.

The mount platform112is configured with one or more lateral platform overhangs134and136; e.g., wings, flanges, projections, etc. One or both of these platform overhangs134and136may have a tapered geometry. A radial thickness of the mount platform112ofFIG. 2, for example, decreases (e.g., tapers) as the mount platform112and its first platform overhang134extend laterally from a laterally intermediate location towards or to the first lateral side130. This change in thickness provides the first platform overhang134with its tapered geometry. The radial thickness of the mount platform112ofFIG. 2also decreases as the mount platform112and its second platform overhang136extend laterally from the laterally intermediate location towards or to the second lateral side132. This change in thickness provides the second platform overhang136with its tapered geometry.

The mount neck114is located radially beneath the mount platform112. The mount neck114extends radially between and is connected (e.g., directly) to the mount platform112and the mount attachment116.

The mount neck114extends laterally between opposing neck lateral sides138and140. The neck first lateral side138is laterally recessed inward from the platform first lateral side130such that the first platform overhang134projects laterally out from the mount neck114. The neck second lateral side140is laterally recessed inward from the platform second lateral side132such that the second platform overhang136projects laterally out from the mount neck114.

Referring toFIG. 3, the mount neck114extends axially along the axial centerline102between a neck first (e.g., forward and/or upstream) side142and a neck second (e.g., aft and/or downstream) side144. The neck first side142is axially recessed inward from the platform first side126such that the mount platform112and its elements134and136project axially out from the mount neck114. The neck second side144is axially recessed inward from the platform second side128such that the mount platform112and its elements134and136project axially out from the mount neck114.

Referring toFIGS. 2 and 3, the mount attachment116is located radially beneath the mount neck114. The mount attachment116ofFIGS. 2 and 3is configured as a dovetail attachment; e.g., a flared attachment, a delta attachment, etc. As best seen inFIG. 3, the mount attachment116extends axially along the axial centerline102between an attachment first (e.g., forward and/or upstream) axial side146and an attachment second (e.g., aft and/or downstream) axial side148. As best seen inFIG. 2, the mount attachment116extends laterally between opposing attachment lateral sides150and152.

The mount attachment116includes one or more attachment pressure surfaces154and156(e.g., engagement surfaces) and a bottom surface158. The first attachment pressure surface154is arranged to the first lateral side150of the mount attachment116and the second attachment pressure surface156is arranged to the second lateral side152of the mount attachment116. The first and the second attachment pressure surfaces154and156may meet (e.g., be joined) at an outer peak of the mount attachment116. The first and the second attachment pressure surfaces154and156may also respectively meet the neck lateral sides138and140at interfaces between the mount attachment116and the mount neck114; see alsoFIG. 3.

Each of the attachment pressure surfaces154,156ofFIGS. 2 and 3is a substantially planar surface. However, in other embodiments, the first attachment pressure surface154and/or the second attachment pressure surface156may have a non-planar (e.g., curved and/or compound angled) geometry. Referring toFIG. 2, the attachment pressure surfaces154,156are angularly offset from one another by an included angle160. This angle160may be greater than sixty degrees (60°) and less than one hundred and forty degrees (140°). The present disclosure, however, is not limited to such exemplary angles. Furthermore, while an angle161between the attachment surface154and a span-line165of the rotor blade104and an angle165between the attachment surface156and the span-line165are shown as equal inFIG. 2(e.g., the mount attachment116may be a symmetric attachment), the angle161may alternatively be different (e.g., greater or less) than the angle165(e.g., the mount attachment116may be an asymmetric attachment) in other embodiments.

The bottom surface158ofFIG. 2extends laterally between respective radial inner ends of the attachment pressure surfaces154and156. The first attachment pressure surface154extends radially between the bottom surface158and the first neck lateral side138. The second attachment pressure surface156extends radially between the bottom surface158and the second neck lateral side140.

Referring toFIG. 3, an axial first end portion162(e.g., a cantilevered projection) of the mount attachment116projects axially out from the neck first side142. The rotor blade mount108is thereby configured with a first gap164(e.g., a recess, a notch, etc.) axially adjacent the mount neck114, which first gap164extends radially between the axial first end portion162of the mount attachment116and the mount platform112. Similarly, an axial second end portion166(e.g., a cantilevered projection) of the mount attachment116projects axially out from the neck second side144. The rotor blade mount108is thereby configured with a second gap168(e.g., a recess, a notch, etc.) axially adjacent the mount neck114, which second gap168extends radially between the axial second end portion166of the mount attachment116and the mount platform112.

Referring toFIGS. 2 and 3, the rotor blade airfoil110is connected (e.g., directly) to the mount platform112. The rotor blade airfoil110projects radially relative to the axial centerline102out from the gas path surface124, in a spanwise direction, to a (e.g., unshrouded) tip170of the rotor blade airfoil110.

Referring toFIG. 4, the rotor blade airfoil110includes a first (e.g., pressure and/or concave) side surface172, a second (e.g., suction and/or convex) side surface174, a (e.g., forward and/or upstream) leading edge176and a (e.g., aft and/or downstream) trailing edge178. The first and second side surfaces172and174extends along a chord line of the rotor blade airfoil110between and meet at the leading edge176and the trailing edge178.

The rotor blade104and its various components108and110ofFIGS. 2-4may be configured together as a monolithic body. The term “monolithic” may describe a single unitary body formed without severable components; e.g., a body formed with integral components. For example, the rotor blade104may be laid up, cast, machined and/or otherwise formed from a single body of material. In another example, the rotor blade104may be formed from a plurality of discretely formed segments which are subsequently permanently bonded together; e.g., welded, adhered, etc. Examples of permanent bonding techniques include, but are not limited to, transient liquid phase (TLP) bonding of one or more components to form a single unitized structure blade pair. These components may be single crystal or poly-crystalline or directionally controlled crystalline structures that are individually oriented in an optimized manner to provide locally desired structural capability. By contrast, the term “non-monolithic” may described a body formed from a plurality of discretely formed bodies that are severable; e.g., may be disassembly from one another. For example, a non-monolithic body may be formed from a plurality of discretely formed segments which are subsequently mechanically attached and/or brazed together. The present disclosure, however, is not limited to monolithic rotor blades104.

The rotor blade104and its various components108and110may be formed from various metallic or non-metallic materials. Examples of the rotor blade materials include, but are not limited to, metal, intermetallic material and/or ceramic. Examples of the metal include, but are not limited to, nickel (Ni), titanium (Ti), aluminum (Al), chromium (Cr) or an alloy of one or more of the foregoing metals; e.g., a single crystal alloy or super alloy. Examples of the intermetallic material include, but are not limited to, TiAl and NiAl. The ceramic may be a monolithic ceramic or a ceramic matrix composite (CMC) material. An example of the monolithic ceramic is, but is not limited to, Si3N4. Examples of the ceramic matrix composite material include, but are not limited to, SiC/SiC and C/SiC. In the case of the ceramic matrix composite material, a fiber reinforcement (e.g., long fibers or woven fibers) within a matrix of the CMC material may be laid to follow at least partially or completely along a longitudinal length of the rotor blade104. With such an arrangement, the fiber reinforcement may substantially remain in tension during operation of the rotor assembly100. The present disclosure, however, is not limited to such an exemplary fiber reinforcement orientation, nor to the foregoing exemplary materials. In the embodiment shown inFIGS. 2 and 3, the rotor blade104is configured as a solid rotor blade. However, in other embodiments, one or more elements including the airfoil110and/or one or more elements of the mount108(e.g.,112,114and/or116) may be hollow in order to reduce the mass of the rotor blade104. The rotor blade104may also or alternatively be hollow to provide one or more flow passages for cooling the airfoil110and/or the gas path surface124of the mount platform112as described below in further detail.

Referring toFIG. 5, the rotor disk assembly106includes a plurality of rotor disks such as a first (e.g., upstream/forward) rotor disk180A and a second (e.g., downstream/aft) rotor disk180B. Each rotor disk180A,180B (generally referred to as “180”) extends circumferentially about (e.g., complete around) the axial centerline102to provide that rotor disk180with a full hoop, annular body. This annular body may be a monolithic body. Alternatively, the annular body may be formed from a plurality of interconnected arcuate circumferential segments; e.g., disk halves, disk thirds, disk quarters, etc.

The first rotor disk180A ofFIGS. 6 and 7includes an inner first hub182A, a first web184A and an outer first rim186A. The first rotor disk180A ofFIG. 6also includes one or more first disk mounts188A; see alsoFIG. 8.

The first hub182A is an annular segment of the first rotor disk180A and defines an inner bore190A through the first rotor disk180A. The first hub182A may be configured as a rotating mass for the first rotor disk180A. The first web184A is connected to and extends radially between the first hub182A and the first rim186A. The first rim186A is arranged at an outer distal end192A of the first rotor disk180A.

In general, the first rim186A has an (e.g., maximum) axial width that is greater than an (e.g., maximum) axial width of the first web184A. The axial width of the first rim186A is less than an (e.g., maximum) axial width of the first hub182A, where the axial width of the first hub182A is also greater than the axial width of the first web184A. The present disclosure, however, is not limited to the foregoing exemplary relationships. For example, in other embodiments, the axial width of the first rim186A may be equal to the axial width of first hub182A.

Referring toFIG. 7, the first web184A is configured with one or more first disk mount apertures194A (e.g., through-holes). These first disk mount apertures194A may be radially intermediately located between the first hub182A and the first rim186A. Note, the first disk mount188A inFIG. 7is shown out of plane for reference in order to illustrate the relative positioning of aperture first disk mount apertures194A.

Referring toFIG. 8, the first disk mount apertures194A are arranged circumferentially around the axial centerline102in an annular array and are interposed with the first disk mounts188A. For example, a respective one of the first disk mounts188A may be positioned circumferentially between each circumferentially adjacent/neighboring pair of the first disk mount apertures194A. Similarly, a respective one of the first disk mount apertures194A may be positioned circumferentially between each circumferentially adjacent/neighboring pair of the first disk mounts188A. Each of these first disk mount apertures194A ofFIG. 8has a circular cross-sectional geometry. However, in other embodiments, one or more or each of the first disk mount apertures194A may have a non-circular geometry (e.g., an elliptical cross-sectional geometry, a polygonal (e.g., rectilinear) cross-sectional geometry, etc.) or any other geometry selected to accommodate a respective one of the disk mounts188B as described below.

Referring toFIGS. 6-8, the first rim186A is configured with one or more first disk pockets196A located at (e.g., on, adjacent or proximate) an outer end of the first rim186A. These first disk pockets196A are arranged circumferentially around the axial centerline102in an annular array. The first disk pockets196A ofFIG. 8are circumferentially interconnected so as to form an (e.g., serrated) annular groove198A in the first rim186A. However, in other embodiments, the first disk pockets196A may be discrete from one another and separated by divider portions200A of the first rim186A as shown, for example, inFIG. 9.

Referring toFIG. 10, each of the first disk pockets196A projects axially along the axial centerline102partially into first rim186A from an axial interior side202A of the first rotor disk180A to a first disk pocket end surface204A. Referring toFIGS. 10 and 11, each of the first disk pockets196A extends radially within the first rim186A from a first disk pocket inner (e.g., bottom) surface206A to a pair of first disk pressure surfaces208A and210A. Each of the first disk pockets196A extends laterally within the first rim186A between the pair of first disk pressure surfaces208A and210A as well as between circumferentially neighboring first disk pockets196A.

The first disk pocket end surface204A extends radially between the first disk pocket inner surface206A and the pair of first disk pressure surfaces208A and210A. The first disk pocket end surface204A extends laterally between the pair of first disk pressure surfaces208A and210A. In the embodiment ofFIG. 11, the first disk pocket end surface204A also extends laterally between pressure surfaces208A,210A of circumferentially neighboring first disk pockets196A. The first disk pocket end surface204A thereby may axially enclose an axial end of a respect first disk pocket196A; seeFIG. 10.

The first disk pressure surface208A is arranged to a first lateral side of the first disk pocket196A and the first disk pressure surface210A is arranged to a second lateral side of the first disk pocket196A. The first disk pressure surfaces208A and210A may meet (e.g., be joined) at an outer peak212A of the first disk pocket196A. The first disk pressure surfaces208A and210A may thereby radially enclose the respective first disk pocket196A within the first rim186A.

Each of the first disk pressure surfaces208A and210A ofFIG. 11is a substantially planar surface. However, in other embodiments, the first disk pressure surface208A and/or the first disk pressure surface208B may have a non-planar (e.g., curved and/or compound angled) geometry. The first disk pressure surfaces208A and210A are angularly offset from one another by an included angle214A. This angle214A may be greater than sixty degrees (60°) and less than one hundred and forty degrees (140°). The present disclosure, however, is not limited to such exemplary angles. In general, the disk pressure surfaces208A and210A are configured to compliment the attachment pressure surfaces154and156to facilitate engagement between the mount attachments116and the first rotor disk180A as described below in further detail; however, such a correspondence is not required. Furthermore, while an angle215A between the first disk pressure surface208A and a ray217A from the centerline102and an angle219A between the first disk pressure surface210A and the ray217A are shown as equal inFIG. 11(e.g., the first disk pocket196A may be a symmetric first disk pocket), the angle215A may alternatively be different (e.g., greater or less) than the angle219A (e.g., the first disk pocket196A may be an asymmetric first disk pocket) in other embodiments.

Referring toFIGS. 6 and 8, the first disk mounts188A are arranged circumferentially around the axial centerline102in an annular array and are interposed with the first disk mount apertures194A as described above. The first disk mounts188A are radially aligned with the first disk mount apertures194A; see alsoFIG. 7. Each first disk mount188A ofFIG. 6is connected to (e.g., formed integral with) the first web184A. Each first disk mount188A projects axially out from and is cantilevered from the first web184A in a first axial direction (e.g., an aft/downstream direction) to a distal first disk mount end216A. Each first disk mount188A may be configured with a first mount slot218A proximate the first disk mount end216A. This first mount slot218A extends axially within the first disk mount188A. The first mount slot218A extends circumferentially through the first disk mount188A. The first mount slot218A extends radially outward and partially into the first disk mount188A to a first slot end surface.

The second rotor disk180B ofFIGS. 12 and 13includes an inner second hub182B, a second web184B and an outer second rim186B. The second rotor disk180B ofFIG. 12also includes one or more second disk mounts188B; see alsoFIG. 14.

The second hub182B is an annular segment of the second rotor disk180B and defines an inner bore190B through the second rotor disk180B. The second hub182B may be configured as a rotating mass for the second rotor disk180B. The second web184B is connected to and extends radially between the second hub182B and the second rim186B. The second rim186B is arranged at an outer distal end192B of the second rotor disk180B.

In general, the second rim186B has an (e.g., maximum) axial width that is greater than an (e.g., maximum) axial width of the second web184B. The axial width of the second rim186B is less than an (e.g., maximum) axial width of the second hub182B, where the axial width of the second hub182B is also greater than the axial width of the second web184B. The present disclosure, however, is not limited to the foregoing exemplary relationships. For example, in other embodiments, the axial width of the second rim186B may be equal to the axial width of second hub182B.

Referring toFIG. 13, the second web184B is configured with one or more second disk mount apertures194B (e.g., through-holes). These second disk mount apertures194B may be radially intermediately located between the second hub182B and the second rim186B. Note, the second disk mount188B inFIG. 13is shown out of plane for reference in order to illustrate the relative positioning of aperture second disk mount apertures194B.

Referring toFIG. 14, the second disk mount apertures194B are arranged circumferentially around the axial centerline102in an annular array and are interposed with the second disk mounts188B. For example, a respective one of the second disk mounts188B may be positioned circumferentially between each circumferentially adjacent/neighboring pair of the second disk mount apertures194B. Similarly, a respective one of the second disk mount apertures194B may be positioned circumferentially between each circumferentially adjacent/neighboring pair of the second disk mounts188B. Each of these second disk mount apertures194B ofFIG. 14has a circular cross-sectional geometry. However, in other embodiments, one or more or each of the second disk mount apertures194B may have a non-circular geometry (e.g., an elliptical cross-sectional geometry, a polygonal (e.g., rectilinear) cross-sectional geometry, etc.) or any other geometry selected to accommodate a respective one of the disk mounts188A as described below.

Referring toFIGS. 12-14, the second rim186B is configured with one or more second disk pockets196B located at (e.g., on, adjacent or proximate) an outer end of the second rim186B. These second disk pockets196B are arranged circumferentially around the axial centerline102in an annular array. The second disk pockets196B ofFIG. 14are circumferentially interconnected so as to form an annular groove198B in the second rim186B. However, in other embodiments, the second disk pockets196B may be discrete from one another and separated by divider portions200B of the second rim186B as shown, for example, inFIG. 15.

Referring toFIG. 16, each of the second disk pockets196B projects axially along the axial centerline102partially into second rim186B from an axial interior side202B of the second rotor disk180B to a second disk pocket end surface204B. Referring toFIGS. 16 and 17, each of the second disk pockets196B extends radially within the second rim186B from a second disk pocket inner (e.g., bottom) surface206B to a pair of second disk pressure surfaces208B and210B. Each of the second disk pockets196B extends laterally within the second rim186B between the pair of second disk pressure surfaces208B and210B as well as between circumferentially neighboring second disk pockets196B.

The second disk pocket end surface204B extends radially between the second disk pocket inner surface206B and the pair of second disk pressure surfaces208B and210B. The second disk pocket end surface204B extends laterally between the pair of second disk pressure surfaces208B and210B. In the embodiment ofFIG. 17, the second disk pocket end surface204B also extends laterally between pressure surfaces208B,210B of circumferentially neighboring second disk pockets196B. The second disk pocket end surface204B thereby may axially enclose an axial end of a respect second disk pocket196B; seeFIG. 16.

The second disk pressure surface208B is arranged to a first lateral side of the second disk pocket196B and the second disk pressure surface210B is arranged to a second lateral side of the second disk pocket196B. The second disk pressure surfaces208B and210B may meet (e.g., be joined) at an outer peak212B of the second disk pocket196B. The second disk pressure surfaces208B and210B may thereby radially enclose the respective second disk pocket196B within the second rim186B.

Each of the second disk pressure surfaces208B and210B ofFIG. 17is a substantially planar surface. However, in other embodiments, the second disk pressure surface208B and/or the second disk pressure surface210B may have a non-planar (e.g., curved and/or compound angled) geometry. The second disk pressure surfaces208B and210B are angularly offset from one another by an included angle214B. This angle214B may be greater than sixty degrees (60°) and less than one hundred and forty degrees (140°). The present disclosure, however, is not limited to such exemplary angles. In general, the disk pressure surfaces208B and210B are configured to compliment the attachment pressure surfaces154and156to facilitate engagement between the mount attachments116and the second rotor disk180B as described below in further detail; however, such a correspondence is not required. Furthermore, while an angle215B between the second disk pressure surface208B and a ray217B from the centerline102and an angle219B between the second disk pressure surface210B and the ray217B are shown as equal inFIG. 17(e.g., the second disk pocket196B may be a symmetric second disk pocket), the angle215B may alternatively be different (e.g., greater or less) than the angle219B (e.g., the second disk pocket196B may be an asymmetric second disk pocket) in other embodiments.

Referring toFIGS. 12 and 14, the second disk mounts188B are arranged circumferentially around the axial centerline102in an annular array and are interposed with the second disk mount apertures194B as described above. The second disk mounts188B are radially aligned with the second disk mount apertures194B; see alsoFIG. 13. Each second disk mount188B ofFIG. 12is connected to (e.g., formed integral with) the second web184B. Each second disk mount188B projects axially out from and is cantilevered from the second web184B in a second axial direction (e.g., a forward/upstream direction) to a distal second disk mount end216B, which second axial direction is opposite the first axial direction. Each second disk mount188B may be configured with a second mount slot218B proximate the second disk mount end216B. This second mount slot218B extends axially within the second disk mount188B. The second mount slot218B extends circumferentially through the second disk mount188B. The second mount slot218B extends radially outward and partially into the second disk mount188B to a second slot end surface.

Each rotor disks180and its various components may be configured as a monolithic body. The present disclosure, however, is not limited to such an exemplary configuration. For example, in other embodiments, the disk mounts188A,188B (generally referred to as “188”) may be discrete from (e.g., removable from) each of the rotor disks180as described below in further detail.

Each of the rotor disks180may be configured from any suitable material such as, but not limited to, metal. Examples of the metal include, but are not limited to, nickel (Ni), titanium (Ti), aluminum (Al), chromium (Cr) or an alloy of one or more of the foregoing metals; e.g., a single crystal alloy or super alloy. The present disclosure, however, is not limited to the foregoing exemplary rotor disk materials, or metal in general. Referring toFIGS. 41-43, one or each of the rotor disks180may also include one or more reinforcing rings400. These reinforcing ring(s)400are configured to assist the respective rotor disks180in carrying loads induced by rotation of the disk180and rotor assembly100. These reinforcing ring(s)400may be integral with one or more disk elements (e.g., bonded into a pocket402,404in or on the disk180, bonded to a flange406on the disk180) or mechanically attached with disk element(s). Each reinforcing ring400may be located within a respective rotor disk180(e.g., within the internal pocket404; seeFIG. 43), axially between the rotor disks180(e.g., in the pocket402and trapped between the webs184; seeFIG. 41) and/or on an outer surface of a respective rotor disk180(e.g., on the flange406; seeFIG. 42). Each reinforcing ring400may be configured as a segmented or unsegmented full hoop body. Each reinforcing ring400may be configured from and/or only include monolithic materials including metallic alloys, laminated or layered materials with two or more materials, or composite materials including metal matrix composite, ceramic matrix composites or organic matric composites. Furthermore, in some embodiments, the rotor assembly100may be configured with both internal and external reinforcing rings400; e.g., any combination of the rings400ofFIGS. 41-43.

Referring toFIGS. 18 and 19, the rotor blades104are mated with the first rotor disk180A and the second rotor disk180B. The rotor blades104, for example, are arranged circumferentially around the axial centerline102in an annular array, and captured between and mounted to the first rim186A and the second rim186B.

The axial first end portion162of each mount attachment116is mated with a respective one of the first disk pockets196A. In particular, the axial first end portion162of each mount attachment116projects axially (in the second axial direction) into the respective first disk pocket196A. The attachment first axial side146is axially adjacent and may be abutted against (e.g., contact or otherwise engage) the first disk pocket end surface204A. A portion of the first rotor disk180A thereby extends laterally across and thereby laterally covers the respective mount attachment116and its axial first end portion162.

Referring toFIG. 20, the attachment pressure surface154is arranged adjacent and configured to engage (e.g., contact) the first disk pressure surface208A. Similarly, the attachment pressure surface156is arranged adjacent and configured to engage the first disk pressure surface210A. As best seen inFIG. 18, a portion220A of the first rotor disk180A projects axially into the first gap164. The first disk portion220A is thereby disposed radially between the axial first end portion162of the respective mount attachment116and the respective mount platform112; see alsoFIG. 20.

With the foregoing interface between the first rotor disk180A and the rotor blades104, the first rotor disk180A may substantially (e.g., completely) radially and circumferentially cover the mount attachments116and the mount necks114. This configuration reduces fluid leakage paths across the first rotor disk180A and, thus, may eliminate or significantly reduce the need for additional sealing devices such as, but not limited to, a rotor disk cover plate for covering attachment slots.

Referring toFIGS. 18 and 19, the axial second end portion166of each mount attachment116is mated with a respective one of the second disk pockets196B. In particular, the axial second end portion166of each mount attachment116projects axially (in the first axial direction) into the respective second disk pocket196B. The attachment second axial side148is axially adjacent and may be abutted against (e.g., contact or otherwise engage) the second disk pocket end surface204B. A portion of the second rotor disk180B thereby extends laterally across and thereby laterally covers the respective mount attachment116and its axial second end portion166.

Referring toFIG. 21, the attachment pressure surface154is arranged adjacent and configured to engage (e.g., contact) the second disk pressure surface208B. Similarly, the attachment pressure surface156is arranged adjacent and configured to engage the second disk pressure surface210B. As best seen inFIG. 18, a portion220B of the second rotor disk180B projects axially into the second gap168. The second disk portion220B is thereby disposed radially between the axial second end portion166of the respective mount attachment116and the respective mount platform112; see alsoFIG. 21.

With the foregoing interface between the second rotor disk180B and the rotor blades104, the second rotor disk180B may substantially (e.g., completely) radially and circumferentially cover the mount attachments116and the mount necks114. This configuration reduces fluid leakage paths across the second rotor disk180B and, thus, may eliminate or significantly reduce the need for additional sealing devices such as, but not limited to, a rotor disk cover plate for covering attachment slots.

Referring toFIGS. 18 and 19, the first rotor disk180A and the second rotor disk180B are mated together. Each of the first disk mounts188A, for example, may be aligned with a respective one of the second disk mount apertures194B; seeFIG. 19. Each of the second disk mounts188B may be aligned with a respective one of the first disk mount apertures194A; seeFIG. 18. The first rotor disk180A and the second rotor disk180B may then be moved (e.g., translated) axially towards one another such that (A) the first disk mounts188A respectively project axially through the second disk mount apertures194B and (B) the second disk mounts188B respectively project axially through the first disk mount apertures194A. A first retention element222A (e.g., a retention ring such as, but not limited to, a split ring) is mated with/seated in the slots218A in the first disk mounts188A (seeFIG. 19) as well as associated slots224A in the second rim186B (seeFIG. 18). Similarly, a second retention element222B (e.g., a retention ring such as, but not limited to, a split ring) is mated with/seated in the slots218B in the second disk mounts188B (seeFIG. 18) as well as associated slots224B in the first rim186A (seeFIG. 19). The first disk mounts188A and the second disk mounts188B thereby connect the first rotor disk180A and the second rotor disk180B together.

In some embodiments, the second disk mounts188B may be configured with the first rotor disk180A such that all of the disk mounts are connected to (e.g., integral with) and project out from the first rotor disk180A; e.g., similar to as shown inFIG. 6. In such embodiments, the second rotor disk180B may be configured without any integral disk mounts (e.g.,188B) and may just include the second disk mount apertures194B. Alternatively, the first disk mounts188A may be configured with the second rotor disk180B such that all of the disk mounts are connected to (e.g., integral with) and project out from the second rotor disk180B; e.g., similar to as shown inFIG. 12. In such embodiments, the first rotor disk180A may be configured without any integral disk mounts (e.g.,188A) and may just include the first disk mount apertures194A.

In some embodiments, referring toFIG. 22, the first disk mounts188A and/or the second disk mounts188B may each be formed discrete from the rotor disks180. For example, each disk mount188may alternatively be configured as a fastener such as, but not limited to, a tie rod/bolt226and a nut228. In such embodiments, each disk mount188projects axially and sequentially through respective apertures194A and194B in the components180A and180B.

In some embodiments, one or more of the rotor disks180may each include one or more (e.g., a circumferential array) of standoffs230A and230B (generally referred to as “230”); e.g., axial projections. These standoffs230are configured to maintain an axial gap between the first rotor disk180A and its first web184A and the second rotor disk180B and its second web184B. The standoffs230, for example, may prevent deformation of the first web184A and the second web184B axially towards one another when the disk mounts188are tightened and secured. In the embodiment ofFIG. 22, each standoff230A is configured to axially engage (e.g., contact) a respective one of the standoffs230B. However, in other embodiments, each standoff230A may directly axially engage the second web184B and each standoff230B may directly axially engage the first web184A. In other embodiments, the first rotor disk180A or the second rotor disk180B may be configured with out the standoffs230.

In some embodiments, referring toFIG. 23, one or more or each of the disk mounts188may be configured with a circular cross-sectional geometry when viewed in a plane perpendicular to the axial centerline102. In some embodiments, referring toFIG. 24, one or more or each of the disk mounts188may be configured with an elongated (e.g., oval, elliptical, etc.) cross-sectional geometry when viewed in a plane perpendicular to the axial centerline102. In some embodiments, referring toFIG. 25, one or more or each of the disk mounts188may be configured with a polygonal (e.g., square, rectangular, triangular, etc.) cross-sectional geometry when viewed in a plane perpendicular to the axial centerline102.

In some embodiments, referring toFIG. 26, one or each rotor disk rim186A and186B (generally referred to as “186”) may be configured as a circumferentially uninterrupted annular rim of the respective rotor disk180. In other embodiments, referring toFIG. 27, one or each rotor disk rim186may be configured as a circumferentially interrupted annular rim. The rotor disk rim186ofFIG. 27, for example, includes one or more (e.g., stress reduction) slots232. Each of these slots232extends axially through the rotor disk rim186and may be aligned with a respective one of the rotor blades104and its mount attachment116. However, the number of slots232may be selected to be less than the number of rotor blades104such that only a select number of the rotor blades104is aligned with a slot232. For example, every other rotor blade104/mount attachment116may be aligned with (e.g., radially and circumferentially overlapped by) one of the slots232such that the other mount attachments116are completely covered by the rotor disk180to reduce fluid leakage thereacross. The present disclosure, however, is not limited to the foregoing exemplary ratio between rotor blades104and slots232. For example, in other embodiments, there could be a3:1,4:1, etc. ratio between the rotor blades104and the slots232.

In some embodiments, referring toFIGS. 28 and 29, the rotor assembly100may be configured with one or more internal vanes234; e.g., fluid pumping vanes. These internal vanes234are configured to direct fluid (e.g., gas such as air) radially through the rotor disk assembly106. The internal vanes234ofFIGS. 28 and 29, for example, are configured to pump (e.g., flow and pressurize) the fluid (e.g., cooling air) received from one or both of the bores190A and190B (generally referred to as “190”) radially, in a radial outward direction, through the rotor disk assembly106towards (e.g., to) the rotor blades104. The fluid may thereby cool the rotor disk assembly106and its rotor disks180. The fluid may then enter internal cooling passages in the rotor blades104(see exemplary passage236inFIG. 29) for cooling the rotor blades104.

Referring toFIG. 29, each of the internal vanes234is arranged within an annulus238(e.g., an annular plenum, passage) axially between the first web184A and the second web184B. Each of the internal vanes234extends longitudinally (e.g., generally radially) along a centerline240of that vane234from a radial inner end242of that vane234to a radial outer end244of that vane234. Each of the internal vanes234extends axially between a vane first side246and a vane second side248. The vane first side246is located at a side of the first web184A and the vane second side248is located at a side of the second web184B. For example, each of the internal vanes234may be connected to (e.g., formed integral with) the first web184A and may project axially out to its vane second side248, where the second side246may axially contact or otherwise engage the second web184B. In another example, each of the internal vanes234may be connected to (e.g., formed integral with) the second web184B and may project axially out to its vane first side246, where the first side246may axially contact or otherwise engage the first web184A. In still another example, some of the internal vanes234may be connected to the first web184A and may axially engage the second web184B, and the remaining internal vanes234may be connected to the second web184B and may axially engage the first web184A. In such embodiments, the vanes234connected to the first web184A may be interposed with the vanes234connected to the second web184B.

Referring toFIG. 28, the internal vanes234are arranged circumferentially around the axial centerline102in an annular array. A circumferential distance between circumferentially neighboring internal vanes234may increase as those vanes extend radially outward away from the axial centerline102.

In the specific embodiment ofFIG. 28, the internal vanes234are interposed with the disk mounts188. For example, a respective one of the disk mounts188may be located circumferentially between each circumferentially neighboring pair of the internal vanes234. Similarly, a respective one of the internal vanes234may be located circumferentially between each circumferentially neighboring pair of the disk mounts188. Of course, in other embodiments, more than one internal vane234may be located circumferentially between one or more or each circumferentially neighboring pair of the disk mounts188, or vice versa. Furthermore, while the internal vanes234radially overlap circumferentially neighboring disk mounts188inFIG. 28, the internal vanes234may be positioned radially outward and/or inward of the circumferentially neighboring disk mounts188in other embodiments.

One or more or each of the internal vanes234may be formed integral with a respective one of the rotor disks180as described above. For example, the rotor disk180and the respective internal vanes234may be formed together from a single mass of material. Alternatively, the internal vanes234may be permanently bonded to the rotor disk180using one or more of the techniques described above, for example. However, in other embodiments, one or more of the internal vanes234may be removably mounted to the rotor disk assembly106. For example, referring toFIGS. 30 and 31, the internal vanes234may be configured into a plurality of tubular structures250that are removably attached to one or each of the rotor disks180.

Referring toFIG. 31, each tubular structure250includes a circumferentially neighboring pair of the internal vanes234. Each tubular structure250also includes a first sidewall252and a second sidewall254. The first sidewall252is disposed at an axial first side of the tubular structure250, and extends laterally between and is connected to the internal vanes234. The second sidewall254is disposed at an axial second side of the tubular structure250, and extends laterally between and is connected the internal vanes234. Each tubular structure250is thereby configured with an internal passage256which is fluidly coupled with the passage(s)236in a respective one (or more) of the rotor blades104; seeFIG. 30.

Referring toFIG. 32, the tubular structures250are arranged circumferentially about the axial centerline102in an annular array. Circumferentially neighboring tubular structures250may be circumferentially spaced from one another so as to form exterior passages258therebetween, where each exterior passage258is fluidly coupled with the passage(s)236in a respective one (or more) of the rotor blades104; seeFIG. 30.

In the specific embodiment ofFIG. 32, the internal vanes234are interposed with the disk mounts188in a similar fashion as described above. With this configuration, a respective one of the disk mounts188may be located circumferentially between each circumferentially neighboring pair of the tubular structures250. In addition, a respective one of the disk mounts188may project axially through the first sidewall252and the second sidewall254of each tubular structure250. Of course, in other embodiments, the disk mounts188may only be positioned in the gap between neighboring tubular structures250. In still other embodiments, the disk mounts188may only be aligned with and, thus, project axially through the tubular structures250.

Referring toFIG. 30, the axial first side and the first sidewall252of the tubular structure250is located at (e.g., abutted axially against or otherwise axially engaged with) the first web184A. The axial second side and the second sidewall254of the tubular structure250is located at (e.g., abutted axially against or otherwise axially engaged with) the second web184B.

Referring toFIG. 33, the axial first side may be mounted to the first rotor disk180A and the axial second side may be mounted to the second rotor disk180B. Each tubular structure250, for example, may include a first mount260and a second mount262. The first mount260ofFIG. 33is configured as a (e.g., cantilevered) first flange located at a distal radial outer end of the tubular structure250. This first flange projects axially (in the second axial direction) into a first groove264in the first rotor disk180A; e.g., in the first web184A. The second mount262ofFIG. 33is configured as a (e.g., cantilevered) second flange located at the distal radial outer end of the tubular structure250. This second flange projects axially (in the first axial direction) into a second groove266in the second rotor disk180B; e.g., in the second web184B.

Referring toFIG. 34, at least a portion (or an entirety) of each internal vane234and its centerline240may be straight. The internal vane234and the centerline240ofFIG. 34, for example, is straight as those elements234,240extend longitudinally between the radial inner end242and the radial outer end244. At least a portion (or an entirety) of the internal vane234and the centerline240may also (or alternatively) be perpendicular to the axial centerline102when viewed, for example, in a plane perpendicular to the axial centerline102. However, referring now toFIG. 35, at least a portion (or an entirety) of each internal vane234and its centerline240may be non-straight; e.g., curved, include angled segments, etc. The internal vane234and the centerline240ofFIG. 35, for example, is curved (e.g., follows a spline, an elliptical or a circular geometry, etc.) as those elements234,240extend longitudinally between the radial inner end242and the radial outer end244. At least a portion (or an entirety) of the internal vane234and the centerline240may also (or alternatively) be non-perpendicular to (e.g., angularly offset from) the axial centerline102when viewed, for example, in a plane perpendicular to the axial centerline102. The internal vanes234of the present disclosure, of course, are not limited to the foregoing exemplary sectional geometries.

Each of the internal vanes234(e.g., seeFIGS. 28-32) as well as each of the tubular structures250and its various components (e.g., seeFIGS. 30-32) is formed from vane material. This vane material may be the same as the rotor disk material, particularly where the internal vane(s)234are formed integral with the rotor disk(s)180. Alternatively, the vane material may be different than the rotor disk material. For example, whereas the rotor disks180may be formed from metal, the internal vanes234/the tubular structures250may be formed from non-metallic materials. The internal vanes234/the tubular structures250, for example, may be formed from a ceramic such as, but not limited to, a ceramic matrix composite (CMC) material. The elements234,250may thereby me formed as light-weight and/or heat resistant components. The present disclosure, however, is not limited to the foregoing exemplary vane materials.

FIG. 36is a side cutaway illustration of a geared turbine engine268with which the rotor assembly100may be included. This turbine engine268extends along the axial centerline102between an upstream airflow inlet270and a downstream airflow exhaust272. The turbine engine268includes a fan section274, a compressor section275, a combustor section276and a turbine section277. The compressor section275includes a low pressure compressor (LPC) section275A and a high pressure compressor (HPC) section275B. The turbine section277includes a high pressure turbine (HPT) section277A and a low pressure turbine (LPT) section277B.

The engine sections274-277are arranged sequentially along the axial centerline102within an engine housing278. This engine housing278includes an inner case280(e.g., a core case) and an outer case282(e.g., a fan case). The inner case280may house one or more of the engine sections275A-277B; e.g., an engine core. The outer case282may house at least the fan section274.

Each of the engine sections274,275A,275B,277A and277B includes a respective rotor284-288, any one of which may be configured as or may include the rotor assembly100ofFIG. 1. The rotor assembly100, for example, may be included in one of the turbine rotors287and288. Each of the rotors284-288ofFIG. 36includes a plurality of rotor blades arranged circumferentially around and connected to one or more respective rotor disks. The rotor blades, for example, may be formed integral with or mechanically fastened, welded, brazed, adhered and/or otherwise attached to the respective rotor disk(s).

The fan rotor284is connected to a gear train290, for example, through a fan shaft292. The gear train290and the LPC rotor285are connected to and driven by the LPT rotor288through a low speed shaft293. The HPC rotor286is connected to and driven by the HPT rotor287through a high speed shaft294. The shafts292-294are rotatably supported by a plurality of bearings296; e.g., rolling element and/or thrust bearings. Each of these bearings296is connected to the engine housing278by at least one stationary structure such as, for example, an annular support strut.

During operation, air enters the turbine engine268through the airflow inlet270. This air is directed through the fan section274and into a core gas path298(e.g., the gas path118inFIGS. 2 and 3) and a bypass gas path300. The core gas path298extends sequentially through the engine sections275A-277B. The air within the core gas path298may be referred to as “core air”. The bypass gas path300extends through a bypass duct, which bypasses the engine core. The air within the bypass gas path300may be referred to as “bypass air”.

The core air is compressed by the compressor rotors285and286and directed into a combustion chamber302of a combustor in the combustor section276. Fuel is injected into the combustion chamber302and mixed with the compressed core air to provide a fuel-air mixture. This fuel air mixture is ignited and combustion products thereof flow through and sequentially cause the turbine rotors287and288to rotate. The rotation of the turbine rotors287and288respectively drive rotation of the compressor rotors286and285and, thus, compression of the air received from a core airflow inlet. The rotation of the turbine rotor288also drives rotation of the fan rotor284, which propels bypass air through and out of the bypass gas path300. The propulsion of the bypass air may account for a majority of thrust generated by the turbine engine268, e.g., more than seventy-five percent (75%) of engine thrust. The turbine engine268of the present disclosure, however, is not limited to the foregoing exemplary thrust ratio.

The rotor assembly100and its components may be included in various turbine engines other than the one described above as well as in other types of rotational equipment. The rotor assembly100and its components, for example, may be included in a geared turbine engine where a gear train connects one or more shafts to one or more rotors in a fan section, a compressor section and/or any other engine section. Alternatively, the rotor assembly100and its components may be included in a turbine engine configured without a gear train. The rotor assembly100and its components may be included in a geared or non-geared turbine engine configured with a single spool, with two spools (e.g., seeFIG. 36), or with more than two spools. The turbine engine may be configured as a turbofan engine, a turbojet engine, a propfan engine, a pusher fan engine or any other type of turbine engine. The present disclosure therefore is not limited to any particular types or configurations of turbine engines or rotational equipment.

FIG. 37is a flow diagram of a method3700for manufacturing a rotor blade. For ease of description, this method3700is described below with reference to forming one of the rotor blades104described above. The method3700, however, is not limited to forming a rotor blade with the exemplary configurations described above with respect to the rotor blades104.

In step3702, an attachment preform304is provided. An exemplary embodiment of the attachment preform304is illustrated inFIG. 38A. This attachment preform304has a tubular body306; e.g., a tubular outer shell. This tubular body306may be formed from one or more layers of material (e.g., see layers inFIG. 39), or may be configured from a three dimensional (3D) braided structure where fibers also extend through the thickness of the shell. The tubular body306may be hollow or filled with filler material308. The filler material308may include a range of materials, examples of which may include, but are not limited to, chopped fibers, metallic or nonmetallic foam, and/or solid material. The attachment preform304is configured to form a base of the mount attachment116; e.g., seeFIGS. 39 and 40. The attachment preform304ofFIG. 38A, for example, is configured with a flared (e.g., tapered, delta-shaped, triangular, etc.) cross-sectional geometry or otherwise dovetailed shaped cross-sectional geometry when viewed, for example, in a plane perpendicular to the axial centerline102; e.g., plane ofFIG. 38A. Referring toFIG. 40, this cross-sectional geometry (or variations thereto) may extend axially along an entire (or partial) length310of the attachment preform304. The attachment preform length310may be between, for example, seventy percent (70%) and one-hundred percent (100%) of a length312of the mount attachment116. The attachment preform length310, for example, may be at least eighty, ninety or ninety-five percent of the mount attachment length312. The present disclosure, however, is not limited to the foregoing exemplary relationship.

In step3704, one or more first sheets of material314are wrapped (e.g., substantially completely) about the attachment preform304to form (1) another portion of the rotor blade mount108(e.g.,112,114and/or116) and (2) at least a portion or an entirety of the airfoil110; e.g., seeFIG. 39. An exemplary embodiment of one of the first sheets of material314is illustrated inFIG. 38B. The first sheet of material314ofFIG. 38Bextends longitudinally along a length thereof between opposing distal ends316and318. The first sheet of material314ofFIG. 38Bis wrapped about the attachment preform304such that its distal ends316and318are aligned radially outboard of the attachment preform304. Referring toFIG. 39, each of the distal ends316,318may be located at (e.g., on, adjacent or proximate) and may thereby form a portion of the rotor blade tip170. Of course, in other embodiments, one or each of the distal ends316,318may be located radially inward of the rotor blade tip170. After wrapping around the attachment preform304, in one alternate embodiment, the first sheet of material314may be stitched or sewn or connected via other techniques with similar or complementary fibers in order to connect one or more surfaces or regions, for example, at the distal ends316and318. With the foregoing configuration, each first sheet of material314may thereby provide a structurally sound connection between the rotor blade airfoil110and the rotor blade mount108and its mount attachment116.

In step3706, one or more second sheets of material320are wrapped about the attachment preform304and over the first sheet(s) of material314to form another portion of the rotor blade mount108(e.g.,112,114and/or116); e.g., seeFIG. 39. The second sheets of material320may be configured from one or more layers of woven material, or one or one or more layers of braided material. An exemplary embodiment of one of the second sheets of material320is illustrated inFIG. 38C. The second sheet of material320ofFIG. 38Cextends longitudinally along a length thereof between opposing distal ends322and324. The second sheet of material320ofFIG. 38Cis wrapped (e.g., substantially completely or partially) about the attachment preform304such that its distal ends322and324are disposed to opposite lateral sides of the attachment preform304; however, the ends322and324may be radially aligned. Referring toFIG. 39, the first distal end322may be located at the first lateral side130such that a corresponding portion of the second sheet of material320at least partially forms the lateral platform overhang134. The second distal end324may be located at the second lateral side132such that a corresponding portion of the second sheet of material320at least partially forms the lateral platform overhang136. Of course, in other embodiments, the first distal end322may be laterally recessed from the first lateral side130and/or the second distal end324may be laterally recess from the second lateral side132. After wrapping around the attachment preform304and first sheet of material314, in one alternate embodiment, the second sheet of material320may be stitched or sewn or connected via other techniques with similar or complementary fibers in order to connect one or more surfaces or regions, for example, at the distal ends322and324. In one embodiment, the location of this connection would be in the thinned region337below the platform112.

In step3708, one or more third sheets of material326are layered over the second sheet(s) of material320to form another (e.g., lateral side) portion of the rotor blade mount108(e.g.,112,114and/or116); e.g., seeFIG. 39. The third sheets of material326may be configured from one or more layers of woven material, or one or one or more layers of braided material. Exemplary embodiments of the third sheets of material326are illustrated inFIG. 38D. Each third sheet of material326ofFIG. 38Dextends longitudinally along a length thereof between opposing distal ends328and330, where the distal ends328and330are arranged on a common side of the attachment preform304. The first distal end328ofFIG. 39, for example, is configured to be aligned with (or proximate to) the platform lateral side130and/or the overhang134. The second distal end330is configured to be aligned with (e.g., overlap), or be adjacent to, the attachment pressure surface154. The third sheet(s) of material326may thereby provide a reinforced interface between the mount attachment116, the mount neck114and the mount platform112and its overhang134. After wrapping around the second sheet of material320, in one alternate embodiment, the third sheet of material326may be stitched or sewn or connected via other techniques with similar or complementary fibers in order to connect one or more surfaces or regions, for example, at the distal ends328and330. In one embodiment, the location of this connection would be in the thinned region337below the platform112.

In step3710, one or more fourth sheets of material332are layered over the second sheet(s) of material320to form another (e.g., lateral side) portion of the rotor blade mount108(e.g.,112,114and/or116); e.g., seeFIG. 39. The fourth sheets of material332may be configured from one or more layers of woven material, or one or one or more layers of braided material. Exemplary embodiments of the fourth sheets of material332are illustrated inFIG. 38D. Each fourth sheet of material332ofFIG. 38Dextends longitudinally along a length thereof between opposing distal ends334and336, where the distal ends334and336are arranged on a common side of the attachment preform304that is opposite the side of the third sheet(s) of material326. The first distal end334ofFIG. 39, for example, is configured to be aligned with (or proximate to) the platform lateral side132and/or the overhang136. The second distal end336is configured to be aligned with (e.g., overlap), or be adjacent to, the attachment pressure surface156. The fourth sheet(s) of material332may thereby provide a reinforced interface between the mount attachment116, the mount neck114and the mount platform112and its overhang136. After wrapping around the third sheet of material326, in one alternate embodiment, the fourth sheet of material332may be stitched or sewn or connected via other techniques with similar or complementary fibers in order to connect one or more surfaces or regions, for example, at the distal ends334and336. In one embodiment the location of this connection would be in the thinned region337below the platform112.

In step3712, the various materials306,308,314,320,326and332are bonded together to form a monolithic rotor blade body. For example, where each of the various materials306,308,314,320,326and332are pre-impregnated/disposed within with a matrix, the matrix may be cured. Alternatively, the various materials306,308,314,320,326and332or some of those materials may be impregnated with/disposed within the matrix and then cured.

The method3700may include additional step other than those described above. The method3700, for example, may include one or more surface machining steps and/or one or more coating steps in order to provide the final rotor blade104.

The foregoing materials306,308,314,320,326,332and any fibers used for stitching, sewing, etc. may be selected to be a common material; e.g., have the same material makeup. Alternatively, one or more of the foregoing materials306,308,314,320,326,332and any fibers used for stitching, sewing, etc. may be different than one or more of the other materials306,308,314,320,326and332.

Each of the foregoing materials306,308,314,320,326and332may be configured as a woven or braded material. Some or all of the stands of the material, for example, may be woven and/or braided together to form the sheet(s) of material. Of course, in other embodiments, one or more of the layers of material may include chopped fibers as filler and/or reinforcement.

One or more or each of the foregoing materials306,308,314,320,326and332may be ceramic, which may be a monolithic ceramic, woven or braided material with one or more fiber types, or a ceramic matrix composite (CMC) material. An example of the monolithic ceramic is, but is not limited to, Si3N4. Examples of the ceramic matrix composite material include, but are not limited to, SiC/SiC and C/SiC. The present disclosure, however, is not limited to the foregoing exemplary materials compositions. The present disclosure is also not limited to ceramic rotor blades. For example, as described above, the rotor blades104may alternatively be formed from metal or intermetallic material. In another example, the rotor blades104may alternatively be formed from a combination of ceramic and metal. Each attachment preform304or a portion thereof (e.g.,306or308), for example, may be configured from or otherwise include metal while the rest of the respective rotor blade104may be configured from or otherwise include one or more of the above-described ceramic materials, or another material different from the metal of the attachment preform304for example. In alternate embodiments, the rotor blades104may contain one or more passages for cooling; e.g., passage(s)236as shown, for example, inFIG. 30.