Patent Application
20250215799
The present disclosure relates to gas turbine engines in general and to integrally bladed rotors used in gas turbine engines in particular.
Integrally bladed rotors (“IBR,” sometimes referred to as a “bladed disk,” or a “blisk”) are often used within modern gas turbine engines. An IBR generally is an array of blades affixed to a disk. In those applications wherein an IBR is a rotor stage, the blades (i.e., “rotor blades”) extend radially outwardly from the disk and are spaced apart from one another around the circumference of the disk. The rotor blades are very often attached to the disk via an attachment technique such as Linear Friction Welding (LFW). IBRs typically have little to no mechanical damping and yet are utilized in challenging environments where high vibratory stresses can be induced. High vibratory stresses can lead to undesirable High Cycle Fatigue (HCF) damage that may limit the life of the component. It would be beneficial to provide a system and/or method for vibrationally damping blades within an IBR, and one that provides flexibility and reliability in blade design.
Some modes for carrying out the present disclosure are presented in terms of the aspects and embodiments detailed herein below. The present disclosure is not limited, however, to the described aspects and embodiments and a person skilled in the art will appreciate that other aspects and embodiments of the present disclosure are possible without deviating from the basic concept of the present disclosure. Headings used herein are for organizational purposes only and are not meant to be used to limit the scope of the description or the enclosed claims. As used throughout this application, the word “may” is used in a permissive sense (i.e., meaning having the potential to), rather than the mandatory sense (i.e., meaning must).
According to an aspect of the present disclosure, an integrally bladed disk is provided that includes a disk and a plurality of rotor blades. The disk has an outer radial hub and is configured for rotation around a rotational axis. Each rotor blade of the plurality of rotor blades has an airfoil that extends chordwise between a leading edge and a trailing edge, and extends spanwise between a base end and a blade tip. Each rotor blade includes a damper pocket, a damper body, and a plug. The damper pocket extends into the airfoil from the base end and has a first tapered configuration. The damper body is disposed within the damper pocket, and has a second tapered configuration. The second tapered configuration of the damper body mates with the first tapered configuration of the damper pocket. The plug is disposed to retain the damper body within the damper pocket.
In any of the aspects or embodiments described above and herein, each rotor blade may include a weld collar affixed to the base end of the airfoil, and the weld collar includes a weld collar aperture that is aligned with the damper pocket and configured to receive the damper body.
In any of the aspects or embodiments described above and herein, the plug for each rotor blade may be affixed to the weld collar.
In any of the aspects or embodiments described above and herein, each rotor blade may be affixed to the outer radial hub of the disk at the weld collar.
In any of the aspects or embodiments described above and herein, the first tapered configuration of the damper pocket (DP) may include a first DP side surface and a second DP side surface, and the first DP side surface and the second DP side surface may converge toward one another. The second tapered configuration of the damper body (DB) may include a first DB side surface and a second DB side surface, and the first DB side surface and the second DB side surface may converge toward one another.
In any of the aspects or embodiments described above and herein, the damper body may be a unitary body.
In any of the aspects or embodiments described above and herein, the damper body may include a plurality of components that collectively form the damper body.
In any of the aspects or embodiments described above and herein, the plurality of components that collectively form the damper body may include a first tapered damper body component, a second tapered damper body component, and a central damper body component.
In any of the aspects or embodiments described above and herein, the damper pocket may include a DP top end surface that extends between the first DP side surface and the second DP side surface, and the damper body may include a DB top end surface that extends between the first DB side surface and the second DB side surface. The damper pocket and the damper body may be disposable in an engaged configuration wherein the first DP side surface is in contact with the first DB side surface and the second DP side surface is in contact with the second DB side surface. In the engaged configuration, the DB top end surface may be spaced apart from the DP top end surface.
In any of the aspects or embodiments described above and herein, the first tapered configuration of the damper pocket (DP) may include a DP top side surface and a single DP side surface that extends circumferentially and extends spanwise from the airfoil base end to the DP top side surface, and converges in a direction from the airfoil base end to the DP top side surface. The second tapered configuration of the damper body (DB) may include a DB top side surface, a DB bottom side surface, and a single DB side surface that extends circumferentially and extends between the DB bottom side surface to the DB top side surface, and converges in a direction from the DB bottom side surface to the DB top side surface.
In any of the aspects or embodiments described above and herein, the first tapered configuration of the damper pocket may be a first truncated cone, and the second tapered configuration of the damper body may be a second truncated cone, and the damper pocket and the damper body are disposable in an engaged configuration wherein the single DB side surface is in contact with the single DP side surface.
In any of the aspects or embodiments described above and herein, in the engaged configuration, the DB top side surface may be spaced apart from the DP top side surface.
In any of the aspects or embodiments described above and herein, the plurality of components that collectively form the damper body may include a first damper body component and a second damper body component, and the second damper body component may nest within the first damper body component.
In any of the aspects or embodiments described above and herein, the damper body may comprise a shape memory alloy.
According to an aspect of the present disclosure, a rotor blade portion of an integrally bladed disk is provided that includes an airfoil, a damper pocket, a damper body, a weld collar, and a plug. The airfoil extends chordwise between a leading edge and a trailing edge, and extends spanwise between a base end and a blade tip. The damper pocket extends into the airfoil from the base end and has a first tapered configuration. The damper body is disposed within the damper pocket and has a second tapered configuration. The second tapered configuration of the damper body mates with the first tapered configuration of the damper pocket. The weld collar is affixed to the base end of the airfoil. The weld collar includes a weld collar aperture that is aligned with the damper pocket and configured to receive the damper body. The plug is disposed within the weld collar aperture and affixed to the weld collar.
The foregoing features and elements may be combined in various combinations without exclusivity, unless expressly indicated otherwise. For example, aspects and/or embodiments of the present disclosure may include any one or more of the individual features or elements disclosed above and/or below alone or in any combination thereof. These features and elements as well as the operation thereof will become more apparent in light of the following description and the accompanying drawings. It should be understood, however, the following description and drawings are intended to be exemplary in nature and non-limiting.
Referring to
The disk 44 is configured to rotate about an axial centerline; e.g., the engine axial centerline 22. The disk 44 includes an outer radial hub 46 that includes an outer radial hub surface 48 to which the rotor blades 42 are directly or indirectly attached. The outer radial hub 46 may assume a variety of different configurations; e.g., a solid hub, an apertured hub and the like. The present disclosure is not limited to any particular disk hub 46 configuration. The rotor blades 42 may be attached to the disk outer radial hub surface 48 using an attachment technique such as Linear Friction Welding (LFW). The present disclosure is not limited to any particular rotor blade attachment technique.
Referring to
In some present disclosure embodiments, a rotor blade 42 may include a body referred to as a “weld collar 66” affixed to the base end 56 of the airfoil 50 or integrally formed with the airfoil 50. The weld collar 66 typically has a larger area “footprint” than the airfoil 50; e.g., an axial dimension that is greater than the chord of the airfoil 50 and a circumferential dimension (perpendicular to the axial direction) that is greater than the thickness of the airfoil 50 (or the degree to which the airfoil 50 is cambered). In these embodiments, the weld collar 66 of each rotor blade 42 is attached to the disk outer radial hub 46. The present disclosure is not limited to any particular weld collar 66 configuration. The rotor blades 42 may be attached to the disk outer radial hub 46 using an attachment technique such as Linear Friction Welding (LFW). The present disclosure is not limited to any particular rotor blade attachment technique. The present disclosure is not limited to IBRs 40 having rotor blades 42 affixed to (or integrally formed with) a weld collar 66. The present disclosure does not require the use of weld collars 66.
As indicated herein, prior art IBRs of which we are aware typically have little or no mechanical damping and are often utilized in environments where high vibratory stresses can be induced within components of the IBR 40; e.g., within the rotor blades 42. The present disclosure provides structure that produces mechanical damping in IBR rotor blades 42 and that damping is understood to be effective in reducing high vibratory stresses and consequent high cycle fatigue (HCF) damage. As will be detailed herein, embodiments of the present disclosure include a rotor blade 42 having a damper pocket 70, a damper body 72, and a plug 74.
Referring to
In some embodiments, the damper pocket 70 may include four sides; e.g., like that shown in
Embodiments of the present disclosure also include at least one damper body 72 configured to be received within and mate with the damper pocket 70 of a rotor blade 42.
The plug 74 is a body that may be utilized to maintain the damper body 72 within the damper pocket 70. In those rotor blade 42 embodiments that include a weld collar 66, the plug 74 may be configured to be received within the weld collar aperture 68. In those rotor blade 42 embodiments that do not include a weld collar 66, the plug 74 may be configured to be received within a portion of the damper pocket 70. The plug 74 is affixed to the weld collar 66 (or airfoil 50) after the damper body 72 is inserted into the damper pocket 70. The plug 74 may be affixed by weldment, or mechanical fastener, or the like. The plug 74 may comprise the same material as the damper body 72, or the same material as the weld collar 66, or a different material.
In some embodiments (like that shown in
The damper body 72 may comprise a variety of different materials. As will be detailed herein, the damper body 72 is configured to frictionally engage with the damper pocket 70 and the frictional engagement therebetween produces a dissipation of vibrational energy and consequent damping of undesirable vibrational modes that may produce high vibratory stresses and High Cycle Fatigue (HCF) damage. Damper body 72 embodiments may comprise any material that is capable of producing the frictional engagement between the damper body 72 and the damper pocket 70 that produces the desired vibrational energy dissipation. In some embodiments, a damper body 72 may be formed from a shape memory alloy (“SMA”); e.g., a metal alloy that may be deformed under certain operating conditions and “remembers” its' shape prior to being deformed. It is understood that in some applications, a damper body 72 formed from a SMA may provide additional inherent damping during material phase changes that the SMA damper body 72 experiences.
In the manufacturing of a present disclosure IBR 40, a damper body 72 (a unitary body or a collective body formed from a plurality of components) is disposed within the damper pocket 70 of a rotor blade 42 to be attached to the disk 44 of the IBR 40. The mating tapered configurations of the damper body 72 and the damper pocket 70 are chosen so that at least one side surface of the damper body 72 engages with a side surface of the damper pocket 70. As indicated, the depth of the damper pocket 70 may exceed the length of the damper body 72 when the damper body 72 is fully received within the damper pocket 70. In those rotor blade 42 embodiments that include a weld collar 66, the damper body 72 may extend into the weld collar aperture 68. After the damper body 72 is disposed within the damper pocket 70/weld collar 66, the plug 74 is inserted into the weld collar aperture 68 and is affixed (e.g., welded) to the weld collar 66. The rotor blade 42 is subsequently attached to the disk hub 46; e.g., via a linear friction welding (LFW) technique. The plug 74 provides an interface between the damper body 72 and the weld collar 66 surface attached to the disk 44 to prevent the rotor blade attachment technique (e.g., LFW) from adversely affecting the damper body 72 during the rotor blade attachment process.
In the operation of the IBR 40, the damper body 72 disposed within each rotor blade 42 portion of the IBR 40 will be subject to centrifugal force as the IBR 40 rotates within the engine 20. The mating tapered configurations of the damper body 72 and the damper pocket 70 facilitates contact between the respective tapered surfaces; e.g., the faster the IBR 40 rotates, the greater the normal force produced by the mass of the damper on the pocket surface. Over time, one or both of the damper body 72 and damper pocket 70 tapered surfaces may frictionally wear. The mating tapered configurations of the damper body 72 and the damper pocket 70 ensure that the desired frictional contact will be maintained. In those embodiments wherein the depth of the damper pocket 70 exceeds the length of the damper body 72 when the damper body 72 is fully received within the damper pocket 70 (e.g., difference “DG”-see
While the principles of the disclosure have been described above in connection with specific apparatuses and methods, it is to be clearly understood that this description is made only by way of example and not as limitation on the scope of the disclosure. Specific details are given in the above description to provide a thorough understanding of the embodiments. However, it is understood that the embodiments may be practiced without these specific details.
It is noted that the embodiments may be described as a process which is depicted as a flowchart, a flow diagram, a block diagram, etc. Although any one of these structures may describe the operations as a sequential process, many of the operations can be performed in parallel or concurrently. In addition, the order of the operations may be rearranged. A process may correspond to a method, a function, a procedure, a subroutine, a subprogram, etc.
The singular forms “a,” “an,” and “the” refer to one or more than one, unless the context clearly dictates otherwise. For example, the term “comprising a specimen” includes single or plural specimens and is considered equivalent to the phrase “comprising at least one specimen.” The term “or” refers to a single element of stated alternative elements or a combination of two or more elements unless the context clearly indicates otherwise. As used herein, “comprises” means “includes.” Thus, “comprising A or B,” means “including A or B, or A and B,” without excluding additional elements.
It is noted that various connections are set forth between elements in the present description and drawings (the contents of which are included in this disclosure by way of reference). It is noted that these connections are general and, unless specified otherwise, may be direct or indirect and that this specification is not intended to be limiting in this respect. Any reference to attached, fixed, connected or the like may include permanent, removable, temporary, partial, full and/or any other possible attachment option.
No element, component, or method step in the present disclosure is intended to be dedicated to the public regardless of whether the element, component, or method step is explicitly recited in the claims. No claim element herein is to be construed under the provisions of 35 U.S.C. 112 (f) unless the element is expressly recited using the phrase “means for.” As used herein, the terms “comprise”, “comprising”, or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
While various inventive aspects, concepts and features of the disclosures may be described and illustrated herein as embodied in combination in the exemplary embodiments, these various aspects, concepts, and features may be used in many alternative embodiments, either individually or in various combinations and sub-combinations thereof. Unless expressly excluded herein all such combinations and sub-combinations are intended to be within the scope of the present application. Still further, while various alternative embodiments as to the various aspects, concepts, and features of the disclosures—such as alternative materials, structures, configurations, methods, devices, and components, and so on—may be described herein, such descriptions are not intended to be a complete or exhaustive list of available alternative embodiments, whether presently known or later developed. Those skilled in the art may readily adopt one or more of the inventive aspects, concepts, or features into additional embodiments and uses within the scope of the present application even if such embodiments are not expressly disclosed herein. For example, in the exemplary embodiments described above within the Detailed Description portion of the present specification, elements may be described as individual units and shown as independent of one another to facilitate the description. In alternative embodiments, such elements may be configured as combined elements. It is further noted that various method or process steps for embodiments of the present disclosure are described herein. The description may present method and/or process steps as a particular sequence. However, to the extent that the method or process does not rely on the particular order of steps set forth herein, the method or process should not be limited to the particular sequence of steps described. As one of ordinary skill in the art would appreciate, other sequences of steps may be possible.
