Nested damper pin and vibration damping system for turbine nozzle or turbine blade

Abstract

To provide a nested damper pin and vibration damping system for a turbine nozzle or blade.SOLUTION: A vibration damping system is provided for a turbine nozzle or blade. A body opening extends through the turbine nozzle or blade. A vibration damping system includes a plurality of stacked damper pins within the body opening. The damper pin includes an outer body part that has an inner opening defined in the outer body and a plurality of side openings penetrating from the inner opening through an outer surface of the outer body, and an inner body is received in the inner opening of the outer body and is movable within the inner opening. The inner body includes a first portion including a plurality of arms, and each arm extends through a respective side opening of the plurality of side openings of the outer body. The end surfaces of the damper pins and the two bodies frictionally engage to dampen vibration.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present disclosure relates generally to damping vibrations in a turbine nozzle or turbine blade, and more particularly to a vibration damping system including a plurality of nested damper pins. [Background technology]

[0002] A concern in turbine operation is the tendency of turbine blades or turbine nozzles to be subjected to vibratory stresses during operation. In many installations, turbines are operated under conditions of frequent acceleration and deceleration. During turbine acceleration and deceleration, the blade airfoils are subjected to vibratory stresses at least momentarily at certain resonant frequencies, and often at secondary or tertiary frequencies. The nozzle airfoils are also subjected to similar vibratory stresses. For example, fluctuations in gas temperature, gas pressure, and / or gas density can cause vibrations throughout the rotor assembly, particularly in the nozzle or blade airfoils. Periodic or "pulsating" gas flows from the turbine and / or compressor sections upstream can also cause undesirable vibrations. When the airfoils are subjected to vibratory stresses, the vibration amplitudes can easily increase to a point that can adversely affect gas turbine operation and / or component life. Traditionally, stacked solid damper pins have been used on turbine blades to dampen vibrations, but centrifugal forces can cause the damper pins to interlock and become stuck, reducing their ability to dampen vibrations. Summary of the Invention

[0003] All aspects, examples, and features described below may be combined in any manner technically possible.

[0004] One aspect of the present disclosure provides a damper pin for a vibration damping system of a turbine nozzle or turbine blade, the damper pin including an outer body portion having an inner opening defined in the outer body portion and a plurality of side openings extending from the inner opening through an outer surface of the outer body portion, and an inner body portion received within the inner opening of the outer body portion and movable within the inner opening, the inner body portion including a first portion including a plurality of arms, each arm extending through a respective side opening of the plurality of side openings of the outer body portion.

[0005] Another aspect of the present disclosure includes any of the aspects above, wherein the plurality of arms define an outer dimension that is greater than an outer dimension of the outer body portion, the outer dimension configured to engage an inner surface of a body opening of the turbine nozzle or turbine blade in which the damper pin is disposed.

[0006] Another aspect of the disclosure includes any of the aspects above, wherein the inner body further includes a second portion having an outer surface configured to frictionally engage the first opening of the inner opening of the outer body, and a third portion extending through and spaced apart from the second opening of the inner opening of the outer body. a first portion of the inner body including the plurality of arms disposed between a second portion and a third portion of the inner body.

[0007] Another aspect of the present disclosure includes any of the aspects above, wherein an outer surface of the second portion of the inner body has a bulbous portion and a first opening portion of the inner opening of the outer body has a concave surface complementary to the bulbous portion.

[0008] Another aspect of the present disclosure includes any of the aspects above, wherein a second opening portion of the inner opening of the outer body portion is spaced from a third portion of the inner body portion by a distance that defines an extent of lateral tilt of the inner body portion within the outer body portion.

[0009] Another aspect of the present disclosure includes any of the aspects described above, wherein an outer surface of the inner body portion and a first opening portion of the inner opening of the outer body portion frictionally engage with the influence of the multiple arms engaging an inner surface of a body opening of the turbine nozzle or turbine blade.

[0010] Another aspect of the present disclosure includes any of the aspects above, wherein the outer body portion further includes a first end face and an opposing second end face, the inner opening of the outer body portion extends through the first end face and the second end face, and the third portion of the inner body portion extends from the inner opening through one of the first and second end faces.

[0011] Another aspect of the present disclosure includes any of the aspects above, wherein the damper pin is one of a plurality of identical damper pins of the vibration damping system, and wherein the first end face of the outer body portion of each respective damper pin is at least partially concave and the second end face of the outer body portion of each respective damper pin is at least partially convex, whereby the first end face of the damper pin is configured to frictionally engage the second end face of an adjacent damper pin.

[0012] Another aspect of the disclosure includes any of the aspects above, wherein the outer body portion and the inner body portion are additively manufactured, and the outer body portion and the inner body portion are integrally joined and secured to one another by removable joining elements prior to separation after the additive manufacturing.

[0013] Another aspect of the present disclosure includes a vibration damping system for a turbine nozzle or turbine blade, the vibration damping system including a plurality of stacked damper pins, each damper pin including: an outer body portion having an inner opening defined in the outer body portion and a plurality of side openings extending from the inner opening through an outer surface of the outer body portion; and an inner body portion received within the inner opening of the outer body portion and movable within the inner opening, the inner body portion including a first portion including a plurality of arms, each arm extending through a respective side opening of the plurality of side openings of the outer body portion.

[0014] Another aspect of the present disclosure includes any of the aspects above, wherein the plurality of arms define an outer dimension that is greater than an outer dimension of the outer body portion, the outer dimension configured to engage an inner surface of a body opening of the turbine nozzle or turbine blade in which the damper pin is disposed.

[0015] Another aspect of the disclosure includes any of the aspects above, wherein the inner body further includes a second portion having an outer surface configured to frictionally engage the first opening of the inner opening of the outer body, and a third portion extending through and spaced apart from the second opening of the inner opening of the outer body. a first portion of the inner body including the plurality of arms disposed between a second portion and a third portion of the inner body.

[0016] Another aspect of the present disclosure includes any of the aspects above, wherein an outer surface of the second portion of the inner body has a bulbous portion and a first opening portion of the inner opening of the outer body has a concave surface complementary to the bulbous portion.

[0017] Another aspect of the present disclosure includes any of the aspects above, wherein a second opening portion of the inner opening of the outer body portion is spaced from a third portion of the inner body portion by a distance that defines an extent of lateral tilt of the inner body portion within the outer body portion.

[0018] Another aspect of the present disclosure includes any of the aspects described above, wherein an outer surface of the inner body portion and a first opening portion of the inner opening of the outer body portion frictionally engage with the influence of the multiple arms engaging an inner surface of a body opening of the turbine nozzle or turbine blade.

[0019] Another aspect of the present disclosure includes any of the aspects above, wherein the outer body portion further includes a first end face and an opposing second end face, the inner opening of the outer body portion extends through the first end face and the second end face, and the third portion of the inner body portion extends from the inner opening through one of the first and second end faces.

[0020] Another aspect of the present disclosure includes any of the aspects above, wherein a first end surface of the outer body portion is at least partially concave and a second end surface of the outer body portion is at least partially convex, whereby the first and second end surfaces of adjacent damper pins frictionally engage.

[0021] Another aspect of the disclosure includes any of the aspects above, wherein the outer body portion and the inner body portion are additively manufactured, and the outer body portion and the inner body portion are integrally joined and secured to one another by removable joining elements prior to separation after the additive manufacturing.

[0022] Another aspect of the present disclosure includes any of the aspects above, further including a retaining damper pin that engages an endmost damper pin of the stacked plurality of damper pins.

[0023] Another aspect of the disclosure includes a method of damping vibrations of a turbine nozzle or turbine blade, the method including damping vibrations during operation of the turbine nozzle or turbine blade by frictional engagement between and among a plurality of stacked damper pins, each damper pin including an outer body portion having an inner opening, a first end face, and an opposite second end face, where a first vibration damping is provided by frictional engagement between the first end face and the opposing second end face of an adjacent damper pin, and an inner body portion received within and movable within the inner opening of the outer body portion, where a second vibration damping is provided by frictional engagement between a portion of an outer surface of the inner body portion and a portion of the inner opening of the outer body portion due to the influence of a plurality of arms that extend from the inner body portion through the outer body portion and engage an inner surface of the body opening of the turbine nozzle or turbine blade.

[0024] Two or more aspects described in this disclosure (including those described in this Summary) may be combined to form implementations not specifically described herein.

[0025] The details of one or more implementations are set forth in the drawings and the detailed description below. Other features, objects, and advantages will become apparent from the description and drawings, and from the claims.

[0026] These and other features of the present disclosure can be readily understood from the following detailed description of the various aspects of the disclosure taken in conjunction with the accompanying drawings illustrating various embodiments of the present disclosure. [Brief description of the drawings]

[0027] [Figure 1] 1 illustrates a cross-sectional view of an exemplary turbomachine in the form of a gas turbine system including a turbine section. [Diagram 2] 2 illustrates a cross-sectional view of a portion of an exemplary turbine section that may be used in the turbomachine of FIG. 1 according to an embodiment of the present disclosure. [Diagram 3]1 illustrates a perspective view of an exemplary turbine nozzle including a vibration damping system in accordance with an embodiment of the present disclosure. [Figure 4] 1 illustrates a perspective view of an exemplary turbine blade including a vibration damping system according to an embodiment of the present disclosure. [Diagram 5] 1 illustrates a schematic cross-sectional view of a turbine nozzle or turbine blade having a vibration damping system including a plurality of damper pins according to an embodiment of the present disclosure. [Figure 6] 1 illustrates a schematic cross-sectional view of a turbine nozzle or turbine blade having a vibration damping system including a plurality of damper pins according to an embodiment of the present disclosure. [Figure 7] 6 is a cross-sectional close-up view of the pair of damper pins of FIG. 5, each damper pin including an outer body portion and an inner body portion, according to an embodiment of the present disclosure. [Figure 8] 8 shows a cross-sectional view of the damper pin of FIGS. 5-7 including an outer body portion and an inner body portion according to another embodiment of the present disclosure. [Figure 9] 9 illustrates a cross-sectional view of the damper pin of FIGS. 5-8 with an inner body portion of the damper pin frictionally engaged with an outer body portion of the damper pin according to an embodiment of the present disclosure. [Figure 10] 1 illustrates a cross-sectional view of an additively manufactured damper pin according to an embodiment of the present disclosure.

[0028] It should be noted that the drawings of the present disclosure are not necessarily drawn to scale. The drawings are intended to depict only typical aspects of the disclosure and therefore should not be considered as limiting the scope of the disclosure. In the drawings, like numbers represent like elements between the drawings. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] First, in order to clearly explain the subject matter of the present disclosure, it becomes necessary to select certain terms when referring to and describing the relevant machine components in the turbine. Wherever possible, common industry terms are used and adopted in a manner consistent with their accepted meaning in the industry. Unless otherwise stated, the above terms should be given a broad interpretation consistent with the context of the present application and the scope of the claims. Those skilled in the art can appreciate that in many cases, a particular component may be referred to using several different or overlapping terms. What is described herein as a single part may in another context include and be referred to as comprising multiple components. Alternatively, what is described herein as comprising multiple components may be referred to elsewhere as a single part.

[0030] Furthermore, some descriptive terms may be used regularly herein, and it is useful to define these terms at the beginning of the detailed description. It is often necessary to describe parts located at different radial positions relative to a central axis. The term "radial" refers to a movement or position perpendicular to the axis. For example, if a first component is closer to the axis than a second component, the first component is described herein as being "radially inward" or "inside" the second component. On the other hand, if a first component is farther from the axis than the second component, the first component can be described herein as being "radially outward" or "outside" the second component. The term "axial" refers to a movement or position parallel to the axis. Finally, the term "circumferential" refers to a movement or position around an axis. It is understood that such terms can be applied with respect to the central axis of a damper pin, the central axis of a turbine blade or turbine nozzle, or the central axis of a turbine.

[0031] Furthermore, certain descriptive terms may be used regularly in this specification, as explained below: The terms "first," "second," and "third" may be used interchangeably to distinguish one component from another, and are not intended to imply the location or importance of the respective components.

[0032] The terms used in the specification are for the purpose of describing particular embodiments only and are not intended to be limiting of the disclosure. As used herein, the singular forms "a", "an" and "the" are intended to include the plural unless the context clearly indicates otherwise. It is further understood that the terms "comprises" and / or "comprising", as used herein, state the presence of a referenced feature, integer, step, operation, element, and / or component, but do not preclude the presence and addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. "Optional" or "optionally" means that the subsequently described event or circumstance may or may not occur, or that the subsequently described component or element may or may not be present, and that the description includes instances in which the event occurs or the component is present as well as instances in which the event does not occur or the component is absent.

[0033] When an element or layer is referred to as being "on," "engaged to," "connected to," or "coupled to" another element or layer, it may be in direct contact with, directly engaged, connected, or coupled to the other element or layer, or there may be intervening elements or layers present. In contrast, when an element is referred to as being "directly on," "directly engaged," "directly connected to," or "directly coupled to" another element or layer, there are no intervening elements or layers present. Other words used to describe relationships between elements should be construed in a similar manner (e.g., "between" and "directly between," "adjacent" and "directly adjacent," etc.). As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0034] An embodiment of the present disclosure provides a vibration damping system for a turbine nozzle or turbine blade. A body opening extends into the turbine nozzle or turbine blade (e.g., extends into an airfoil among other possible portions of the nozzle or blade). The vibration damping system includes a plurality of stacked damper pins within the body opening. Each damper pin includes an outer body portion having an inner opening defined therein and a plurality of side openings extending from the inner opening through an outer surface of the outer body portion, the inner body portion being received within the inner opening of the outer body portion and movable within the inner opening. Thus, the damper pin may be referred to as a "nested damper pin" since it includes nested parts that frictionally engage with each other to damp vibration. The inner body portion includes a first portion including a plurality of arms, each arm extending through a respective one of the plurality of side openings of the outer body portion. The inner body portion also includes a second portion having an outer surface configured to frictionally engage a portion of the inner opening of the outer body portion to damp vibration. Additionally, the end faces of the outer body portions of adjacent damper pins frictionally engage adjacent damper pins so as to dampen vibrations.

[0035] The vibration damping system reduces vibration of the nozzle or blade in a simple manner and does not add significant extra mass to the nozzle or blade. Thus, the vibration damping system and pin do not increase the centrifugal forces acting on the nozzle base or blade tip, and do not require changes to the nozzle or blade geometry. A nested damper pin can be used such that if the ends of the outer body parts interlock and become stuck (as may occur, for example, with turbine blades as a result of centrifugal forces on the turbine blades), the inner body part of the damper pin is free to continue its vibration damping motion using friction (due to the interaction of the arm with the inner surface of the body opening of the turbine nozzle or turbine blade).

[0036] Referring to the drawings, Figure 1 is a cross-sectional view of an exemplary machine including a turbine (e.g., an expansion turbine or turbine section) to which the teachings of the present disclosure may be applied. In Figure 1, a turbomachine 90 is shown in the form of a combustion turbine system or gas turbine (GT) system 100 (hereinafter "GT system 100"). The GT system 100 includes a compressor 102 and a combustor 104. The combustor 104 includes a combustion region 105 and a fuel nozzle section 106. The GT system 100 also includes a turbine 108 and a common compressor / turbine shaft 110 (hereinafter "rotor 110").

[0037] The GT system 100 may be, for example, a 7HA.03 engine available from General Electric Company, Greenville, South Carolina. The present disclosure is not limited to any particular GT system and may be implemented in other engines (e.g., other HA, F, B, LM, GT, TM and E class engine models from General Electric Company and engine models from other companies). More importantly, the teachings of the present disclosure do not necessarily apply only to the turbine of a GT system, but may be applied to virtually any type of industrial machine or other turbine (e.g., steam turbine), jet engine, compressor (as shown in FIG. 1), turbofan, turbocharger, etc. Thus, reference to the turbine 108 of the GT system 100 is for illustrative purposes only and is not intended to be limiting.

[0038] FIG. 2 illustrates a cross-sectional view of an exemplary portion of a turbine 108. In the illustrated example, the turbine 108 includes four stages L0-L3 that may be used in the GT system 100 of FIG. 1. The four stages are designated L0, L1, L2, and L3. Stage L0 is the first stage and is the smallest (radially) of the four stages. Stage L1 is the second stage and is disposed axially adjacent to the first stage L0. Stage L2 is the third stage and is disposed axially adjacent to the second stage L1. Stage L3 is the fourth, final, and largest stage (radially). It is understood that four stages are shown by way of example only and each turbine may have more or less than four stages.

[0039] A plurality of stationary turbine vanes or nozzles 112 (hereinafter "nozzles 112" or "nozzles 112") may cooperate with a plurality of rotating turbine blades 114 (hereinafter "blades 114" or "blades 114") to form respective stages L0-L3 of the turbine 108 and define a portion of a working fluid path through the turbine 108. The blades 114 of each stage are coupled to the rotor 110 (FIG. 1), for example, by respective rotor wheels 116 that circumferentially couple the blades to the rotor 110 (FIG. 1). That is, the blades 114 are mechanically coupled to the rotor 110, for example, by the rotor wheels 116, in circumferentially spaced apart relation. The static nozzle section 115 includes a plurality of nozzles 112 mounted to a casing 124, the nozzles 112 being circumferentially spaced apart about the rotor 110 (FIG. 1). It can be seen that the blades 114 rotate with the rotor 110 (FIG. 1) and are therefore subjected to centrifugal forces, while the nozzles 112 are stationary.

[0040] 1 and 2. In operation, air flows through the compressor 102 and the compressed air is delivered to the combustor 104. Specifically, the compressed air is delivered to a fuel nozzle section 106 integrated into the combustor 104. The fuel nozzle section 106 is in fluid communication with a combustion zone 105. The fuel nozzle section 106 is also in fluid communication with a fuel source (not shown in FIG. 1 ) to deliver fuel and air to the combustion zone 105. The combustor 104 ignites and combusts the fuel to generate combustion gases. The combustor 104 is in fluid communication with a turbine 108, where the combusted fuel (e.g., a working fluid) is delivered to a working fluid path in which thermal energy from the combustion gas flow is converted to mechanical rotational energy to rotate blades 114. The turbine 108 is rotatably coupled to and drives a rotor 110. The compressor 102 may also be rotatably coupled to the rotor 110. At least one end of the rotor 110 extends axially away from the compressor 102 or the turbine 108 and may be attached to a load or machine (not shown) (such as, but not limited to, an electrical generator, a load compressor, and / or another turbine).

[0041] Figures 3 and 4 show perspective views of a (stationary) nozzle 112 and a (rotating) blade 114, respectively, of a type that may be used with embodiments of the present disclosure's vibration damping system 120. As described herein, Figures 5 and 6 show schematic cross-sectional views of a nozzle 112 or a blade 114 including a vibration damping system 120 according to various embodiments of the present disclosure.

[0042] 3 and 4, each nozzle 112 or blade 114 includes a body portion 128 having a base end 130, a tip end 132, and an airfoil 134 extending between the base end 130 and the tip end 132. As shown in FIG. 3, the nozzle 112 includes an outer endwall 136 at the base end 130 and an inner endwall 138 at the tip end 132. The outer endwall 136 couples to the casing 124 (FIG. 2). As shown in FIG. 4, the blade 114 includes a dovetail 140 at the base end 130 that attaches the blade 114 to a rotor wheel 116 (FIG. 2) of the rotor 110 (FIG. 2). The base end 130 of the blade 114 may further include a shank 142 extending between the dovetail 140 and a platform 146. A platform 146 is disposed at the junction of the airfoil 134 and the shank 142 and defines a portion of the inner boundary of the working fluid path of the turbine 108 (FIG. 2).

[0043] It is understood that the airfoils 134 of the nozzles 112 and blades 114 are the components that interrupt the flow of working fluid at the nozzles 112 or blades 114 and, in the case of the blades 114, rotate the rotor 110 (FIG. 1). It is seen that the airfoils 134 of the nozzles 112 and blades 114 include a concave pressure side (PS) outer sidewall 150 and a circumferentially or laterally opposed convex suction side (SS) outer sidewall 152, which extend axially between opposed leading and trailing edges 154 and 156. The sidewalls 150 and 152 extend radially from a base end 130 (i.e., the outer endwall 136 for the nozzles 112 and the platform 146 for the blades 114) to a tip end 132 (i.e., the inner endwall 138 for the nozzles 112 and the tip 158 for the blades 114). In the illustrated example, blade 114 does not include a tip shroud, however, it should be noted that the teachings of this disclosure are equally applicable to blades that include a tip shroud at tip 158. The nozzle 112 and blade 114 shown in Figures 3-4 are exemplary only, and the teachings of this disclosure may be applied to a wide variety of nozzles and blades.

[0044] During turbine operation, the nozzles 112 or blades 114 vibrate due to several influences that apply different forces. For example, fluctuations in temperature, pressure, and / or density of the working fluid can cause vibrations throughout the rotor assembly, particularly within the airfoils and / or tips of the blades 114 or nozzles 112. Periodic (or "pulsating") exiting gases from the upstream turbine and / or compressor sections can also cause undesirable vibrations. Embodiments of the present disclosure reduce vibrations in the stationary nozzles 112 or rotating turbine blades 114 without significant changes to the nozzle or blade design.

[0045] 5 and 6 each show a schematic cross-sectional view of a nozzle 112 or blade 114 including a vibration damping system 120 according to an embodiment of the present disclosure. (The nozzle 112 in the schematic cross-sectional views of FIGS. 5-6 is shown vertically inverted and without an inner end wall 138 compared to the nozzle shown in FIG. 3 for ease of illustration. It should be understood that the nozzle 112 has the referenced proximal and distal ends 130 and 132 reversed compared to the blade 114.) The vibration damping system 120 for the nozzle 112 or blade 114 can include a body opening 160. The body opening 160 is disposed at least partially in the body portion 128 between the distal and proximal ends 132 and in the airfoil 134. The body opening 160 can extend a portion of the distance between the proximal and distal ends 130 and 132, or can extend through one or more of the proximal and distal ends 130 and 132. The body opening 160 may be defined in any portion of the structure of the body portion 128. For example, if the body portion 128 includes an interior partition wall (not shown) for defining a cooling circuit within the body portion 128, the body opening 160 may be defined as an interior cavity of the partition wall of the body portion 128. The body opening 160 generally extends radially within the body portion 128. However, the body opening 160 may be angled (or curved) to some degree relative to the radial direction of the body portion 128. The body opening 160 has an interior surface 162.

[0046] The body opening 160 may originate at the proximal end 130 of the nozzle 112 or blade 114 as shown in FIG. 5 or may originate at the distal end 132 of the nozzle 112 or blade 114 as shown in FIG. 6. More specifically, the body opening 160 may open at the proximal end 130 and terminate at the distal end 132 as shown in FIG. 5 or may open at the distal end 132 and terminate at the proximal end 130 as shown in FIG. 6. The open end may aid in assembling the vibration damping system 120 to the nozzle 112 or blade 114 or may allow the system to be attached to an existing nozzle or blade. If the body opening 160 passes through the proximal end 130 as shown in FIG. 5, a closure member 164 may be provided to close the body opening 160. If the body opening 160 passes through the distal end 132 as shown in FIG. 6, a closure member 166 may be provided for the body opening 160. In addition to closing the body opening 160 , the closure members 164 , 166 also prevent the vibration damping system 120 from slipping out of the body opening 160 .

[0047] The vibration damping system 120 for the nozzle 112 or blade 114 may include a plurality of stacked damper pins 174. As shown in the enlarged cross-sectional views of Figures 7 and 8, each damper pin 174 may include an outer body portion 176 having an inner opening 178 therein and a plurality of side openings 180 extending from the inner opening 178 through an outer surface 182 of the outer body portion 176. The outer body portion 176 may also include a first end surface 184 and an opposing second end surface 186.

[0048] The outer body portion 176 can have an outer surface 182 shaped and sized to fit inside the body opening 160. More specifically, the body opening 160 has an inner surface 162 having an inner dimension ID1, and each outer body portion 176 has an outer dimension OD1 sized to slidably fit (but not necessarily fully engage) the inner dimension ID1 of the body opening 160. That is, the outer dimension OD1 of the outer body portion 176 of each damper pin 174 does not always rub or contact the inner surface 162 of the body opening 160. During assembly, the inner dimension ID1 and outer dimension OD1 are sized to allow the damper pins 174 to be positioned within the body opening 160. In one non-limiting example, the difference between the outer dimension OD1 of the outer body portion 176 of the damper pin 174 and the inner dimension ID1 of the inner surface 162 of the body opening 160 can be in the range of approximately 1 to 10 millimeters (mm), thereby allowing the damper pin 174 to be inserted into the airfoil 134 of the nozzle 112 or blade 114 and for the damper pin 174 to move relative to it.

[0049] The first end surface 184 and the second end surface 186 of the outer body portion 176 are complementary to one another, i.e., the end surfaces 184 and 186 mate with one another so that they can frictionally engage one another. In the embodiment of FIGS. 5-8, the first end surface 184 of the outer body portion 176 is at least partially concave, and the second end surface 186 of the outer body portion 176 is at least partially convex. In this manner, the first end surface 184 and the second end surface 186 of adjacent damper pins 174 can frictionally engage and rotate relative to one another as the nozzle 112 or blade 114 moves. The end surfaces 184, 186 need not be continuously contacting surfaces, but may be segmented (as shown), for example, to reduce unnecessary weight from each damper pin 174. Other complementary shapes for the end surfaces 184, 186 are possible, such as planar ends. One way that the damper pins 174 damp vibrations is by frictionally engaging the outer body portions 176 of adjacent pins with one another (i.e., through the end faces 184, 186). In the nozzle 112, the damper pins 174 frictionally engage under the force of the damper pin's overall weight, and in the blade 112, the damper pins 174 frictionally engage under the force of the damper pin's overall weight and the centrifugal forces acting on the blade as it rotates. The outer body portion 176 also includes an inner opening 178 that extends through the first end face 184 and the second end face 186. As will be described below, the inner opening 178 has several different surfaces to accommodate different portions of the inner body portion 190.

[0050] Each damper pin 174 may include an inner body portion 190 that is received within and movable within an inner opening 178 of the outer body portion 176. The inner body portion 190 moves independently of the outer body portion 176. The inner body portion 190 includes a first portion 192 (FIGS. 7-8) that includes a plurality of arms 194. Each arm 194 passes through a respective one of the plurality of side openings 180 of the outer body portion 176. The plurality of arms 194 collectively define an outer dimension OD2 that is greater than the outer dimension OD1 of the outer body portion 176. The outer dimension OD2 of the arms 194 is configured to engage an inner surface 162 of a body opening 160 of the turbine nozzle 112 or turbine blade 114 in which the damper pin 174 is disposed as the turbine nozzle 112 or blade 114 vibrates.

[0051] In the illustrated example, four arms 194 are shown at each side opening 180 (one of the four arms is not visible). However, any number of arms 194 and respective side openings 180 can be provided, for example, two, three, five or six arms, so long as sliding movement occurs between the outer body portion 176 and the inner body portion 190. Although the side openings and arms are shown as being in equal numbers, it is not necessary that arms 194 are present at all side openings 180, i.e., some side openings may be absent. The side openings 180 are sized so as not to impede movement of the arms 194 during operation of the vibration damping system 120. The outer dimensions of the outer body portion 176 can be tapered where the side openings 180 are defined, for example to reduce weight and the amount of material required.

[0052] The arms 194 can be shaped to provide sufficient structural strength to move the inner body portion 190 relative to the outer body portion 176. In the illustrated example, the arms 194 are generally triangular in shape with flat outer ends 195 that engage the inner surface 162 of the body opening 160. The flat outer ends 195 can be configured to be parallel to the inner surface 162 of the body opening 160, for example, during insertion of the damper pin 174. Alternatively, the flat outer ends 195 of the arms 194 can be angled slightly from parallel to the inner surface 162 of the body opening 160, for example, to aid in insertion of the damper pin 174 and ensure smooth engagement with the inner surface 162 of the body opening 160 during use. The flat-formed outer end 195 may have any surface roughness (e.g., a surface roughness rougher than the inner surface 162 of the body opening 160) to ensure that it can be properly inserted into the body opening 160 and operatively engage with the inner surface 162 of the body opening 160.

[0053] The inner body portion 190 and the inner opening 178 of the outer body portion 176 can take a variety of forms. In a particular embodiment, as shown in FIGS. 7-8, the inner body portion 190 has a second portion 196 configured to frictionally engage with a first opening 198 of the inner opening 178 of the outer body portion 176. More specifically, the outer surface 200 of the second portion 196 of the inner body portion 190 can have a bulbous portion 202, and the first opening 198 of the inner opening 178 of the outer body portion 176 can have a concave surface 204 that is complementary to the bulbous portion 202. In this manner, the bulbous portion 202 and the concave surface 204 can frictionally engage as the inner body portion 190 moves laterally or tilts within the outer body portion 176 during vibration and / or flexing of the nozzle 112 or blade 114. The bulbous portion 202 can be solid or hollow internally (see FIG. 10 for the latter). The engagement of the bulbous portion 202 and the concave surface 204 is configured to define a range of radial movement (relative to the turbine shaft) of the inner body portion 190 relative to the respective outer body portion 176 .

[0054] The inner body 190 may also include a third portion 210 that passes from the inner opening 178 through one of the first end face 184 and the second end face 186. In the illustrated example, the third portion 210 passes from the inner opening 178 through the second end face 186. As will be further described, the third portion 210 passes through a spaced (radially) distance from a second opening 212 of the inner opening 178 of the outer body 176. The third portion 210 of the inner body 190 may have any shape configured to pass through the second opening 212. In one non-limiting example, the third portion 210 includes a cylindrical element 214 that extends axially from the first portion 192 that includes the plurality of arms 194. As shown in FIG. 7, the third portion 210 may extend outwardly beyond the end surface 186 of the outer body portion 176, or may be inboard of the second opening 212 of the outer body portion 190 (i.e., flush with or inboard of the end of the second opening 212) as shown in FIG. 8. As shown, the first portion 192 of the inner body portion 190 includes a plurality of arms 194 and is disposed between the second portion 196 (the portion having the bulbous portion 202) and the third portion 210 of the inner body portion 190. As shown in FIG. 8, the second opening 212 of the inner opening 178 of the outer body portion 176 is spaced from the third portion 210 of the inner body portion 190 by a distance D that defines the extent of the amount that the inner body portion 190 will tilt laterally within the outer body portion 176 during use. More specifically, as shown in FIG. 9 , as the inner body portion 190 moves within the outer body portion 176 with assistance from the arms 194 that engage the inner surface 162 of the body opening 160, the third portion 210 of the inner body portion 190 can move laterally until it contacts the second opening portion 212 of the inner opening 178.

[0055] The portions 192, 196, 210 of the inner body portion 190 are integral with one another, i.e., of unitary construction, however, the inner body portions 190 of adjacent damper pins 174 do not contact one another and move independently of one another.

[0056] With respect to the damper pins 174, any number of damper pins 174 may be used in the vibration damping system 120 depending, among other things, on the length of the nozzle 112 or blade 114, the vibration damping desired, and / or the space available. The endmost damper pin of the stacked plurality of damper pins 174 may abut the end 252 of the body opening 160 (see, for example, FIG. 7). Alternatively, as shown in FIGS. 5 and 6, a retaining damper pin 250 may be positioned to engage the endmost damper pin 174 of the stacked plurality of damper pins 174. The retaining damper pin 250 may act to protect the endmost damper pin 174 of the stacked plurality of damper pins 174 near the end 252 of the body opening 160. In this case, the damper pin 174 abuts the retaining damper pin 250 rather than the end 252 of the body opening 160, which abuts the end 252 of the body opening 160.

[0057] 5 illustrates an embodiment in which the body opening 160 is closed at the tip 132 of the nozzle 112 or blade 114 and the closure member 164 closes the base end 130. In the illustrated example, the retaining damper pin 250 is positioned on the overlapping damper pin 174 at the tip 132 of the nozzle 112 or blade 114 to prevent the overlapping damper pin 174 from hitting the end 252 of the body opening 160. As previously mentioned, the damper pin 174 may alternatively abut the end 252 of the body opening 160 at the tip 132. As the blade rotates, the centrifugal force of the blade 114 (arrows CF) presses the overlapping damper pin 174 against the retaining damper pin 250 and / or the end 252 of the body opening 160 at the tip 132 of the body portion 128 of the turbine blade 114. Similarly, for a static nozzle 112, the weight of the damper pin 174 presses the damper pin 174 against the closure member 164. The body opening 160 at the proximal end 130 may be closed by a now known or later developed closure member 164.

[0058] 6 illustrates an embodiment in which the body opening 160 is closed at the proximal end 130 of the nozzle 112 or blade 114, and the closure member 166 closes the distal end 132. In the illustrated example, a retaining damper pin 250 is positioned on the stacked damper pins 174 at the proximal end 130 of the nozzle 112 or blade 114 to prevent the stacked damper pins 174 from hitting the end 252 of the body opening 160. As previously mentioned, the damper pins 174 may alternatively abut the end 252 of the body opening 160 at the proximal end 130. Here, as the blade rotates, the centrifugal force of the blade 114 presses the stacked damper pins 174 against the closure member 166 at the distal end 132 of the body portion 128 of the turbine blade 114. Similarly, during use with the static nozzle 112, the weight of the damper pin 174 presses the damper pin 174 against the retaining damper pin 250 at the proximal end 130 and / or the inner edge 252 of the body opening 160 at the proximal end 130. The body opening 160 at the distal end 132 can be closed by a now known or later developed closure member 166.

[0059] The operation of the vibration damping system 120 will now be described. In operation, as shown in FIG. 9, the first end face 184 and the second end face 186 of adjacent damper pins 174 frictionally engage and rotate relative to each other as the nozzle 112 or blade 114 moves. In this manner, the damper pins 174 damp vibrations by frictionally engaging the outer body portions 176 of adjacent damper pins 174 (i.e., frictionally engaging the end faces 184, 186). In the nozzle 112, the damper pins 174 frictionally engage as described above under the influence of the force due to the total weight of the damper pins, and in the blade 112, the damper pins 174 frictionally engage under the influence of the total weight of the damper pins and the centrifugal force acting on the blade during the rotation of the blade. In the pages in which FIG. 5 and FIG. 6 are shown, the centrifugal force is applied upwards (see arrows CF).

[0060] As the nozzle 112 or blade 114 vibrates, the body portion 128 of the nozzle 112 or blade 114 flexes, simultaneously with the vibration damping described above. As this flexing occurs, frictional engagement occurs between the outer surface of the inner body portion 190 and the inner surface of the inner opening 178, which also damps vibration. The frictional engagement may occur between the outer surface 200 of the bulbous portion 202 of the inner body portion 190 and the concave surface 204 of the first opening 198 of the inner opening 178 of the outer body portion 176. In contrast to the vibration damping between the end faces 184, 186, the inner body portion 190 is free to move away from the outer body portion 176, so the frictional engagement described here occurs solely based on forces acting on the inner body portion 190. More specifically, the frictional engagement, for the nozzles 112, is caused by the weight of each inner body portion 190, and for the blades 114, is caused by the weight of each inner body portion 190 and the centrifugal force acting on each inner body portion 190.

[0061] The frictional engagement between the surfaces 200, 204 may also result from one or more of the arms 194 engaging the inner surface 162 of the body opening 160 of the turbine nozzle 112 or turbine blade 114. More specifically, the arms 194 have the largest outer diameter dimension OD2 of the damper pin 174, so that the arms contact the inner surface 162 of the body opening 160 before any other portion of the damper pin 174. This configuration provides an earlier point of contact (compared to the outer surface 182 of the outer body portion 176 engaging the inner surface 162 of the body opening 160), which allows each damper pin 174 (i.e., the inner body portion 190 of each damper pin 174) more movement than previous damper pins, providing greater amounts of movement and further vibration damping using friction. As the arms 194 engage the inner surface 162 of the body opening 160 (e.g., as the airfoil 134 flexes during operation, moving the inner body portion 190 through the arms 194), the inner body portion 190 may move, rock, or tilt relative to the outer body portion 176, resulting in a large amount of movement and further frictional vibration damping. Note that the frictional engagement may occur anywhere on the outer surface of the inner body portion 190 and the inner surface of the inner opening 178 of the outer body portion 176, but mostly occurs on the outer surface 200 of the bulbous portion 202 of the inner body portion 190 and the concave surface 204 of the first opening 198 of the outer body portion 176. For example, the frictional engagement occurs near the top of the bulbous portion 202 and the concave surface 204 of the outer body portion 176 (i.e., where the concave surface 204 widens to accommodate the shape of the inner body portion 190) (as shown in FIG. 9 ). Frictional engagement may occur at other locations between the outer surface 200 and the concave surface 204 of the bulbous portion 202 as well.

[0062] 5 and 6. Contrasting the operation between the nozzle 112 and the blade 114, for the nozzle 112, only the weight of the inner body 190 frictionally engages the surfaces 200, 204, and the weight of the damper pins 174 (radially stacked damper pins) frictionally engages the end faces 184, 186. For the nozzle 112, the lower portion (as shown) of each surface 200, 204 frictionally engages. In contrast, for the blade 114, each damper pin 174 experiences the centrifugal force of its radially inward (with respect to the turbine shaft) damper pin 174 (at the end faces 184, 186 of the outer body 176 of each damper pin), which can cause the damper pins to bind and / or not move smoothly relative to each other over time, resulting in less vibration damping. In either case, because the inner body portion 190 is nested within the outer body portion 176, the frictional engagement surfaces 200, 204 are not subjected to as much force as the frictional engagement end surfaces 184, 186. Thus, even if the end faces 184, 186 of adjacent damper pins 174 bind and reduce vibration damping, the inner body portion 190 is less likely to bind and the inner body portion 190 is more likely to maintain freedom of movement and continue to dampen vibrations.

[0063] Vibration damping may also occur due to frictional engagement between the outer dimension OD 1 of the exterior surface 182 of the outer body portion 176 and the inner dimension ID 1 of the interior surface 162 of the body opening 160 of the nozzle 112 or blade 114 .

[0064] In view of the above, a method for damping vibrations of a turbine nozzle 112 or turbine blade 114 may include several vibration damping processes during operation of the nozzle 112 or blade 114. The vibration damping may occur through frictional engagement between and within the stacked damper pins 174. As previously described, each damper pin 174 includes an outer body portion 176 having an inner opening 178, a first end face 184, and an opposing second end face 186. The vibration damping may occur through frictional engagement between the first end face 184 and the opposing second end face 186 of an adjacent damper pin 174. In FIGS. 5-7 and 9, the complementary concave and convex end faces 184, 186 frictionally engage to dampen vibrations. As previously described, the end faces 184, 186 may have other complementary shapes that may dampen vibrations through frictional engagement.

[0065] Each damper pin 174 also includes an inner body portion 190 received within and movable within an inner opening 178 of the outer body portion 176. As described herein, additional vibration damping occurs through frictional engagement between a portion of an outer surface 200 of the inner body portion 190 and an opening portion 198 (e.g., concave surface 204) of the inner opening 178 of the outer body portion 176, particularly due to the influence of a plurality of arms 194 engaging an inner surface 162 of the body opening 160 of the turbine nozzle 112 or turbine blade 114. As previously mentioned, the method may also include vibration damping through frictional engagement between an outer dimension OD1 of the outer surface 182 of the outer body portion 176 and an inner dimension ID1 of the inner surface 162 of the body opening 160 of the nozzle 112 or blade 114.

[0066] The damper pin 174 can be manufactured in a known or future developed manner. For example, the outer body portion 176 and the inner body portion 190 can be cast, the outer body portion 176 can be halved, and the parts assembled (e.g., assembled by placing the halves of the outer body portion 176 around the inner body portion 190 and welding or otherwise fastening them together). With reference to FIG. 10, in one embodiment, the outer body portion 176 and the inner body portion 190 can be additively manufactured. Any form of additive manufacturing appropriate for the materials used can be employed, such as, but not limited to, direct metal laser melting (DMLM). In this case, the outer body portion 176 and the inner body portion 190 are integrally joined and secured to one another by removable joining elements 260 before being separated after additive manufacturing. In this manner, the outer body portion 176 can be additively manufactured around the inner body portion 190 with the outer body portion 176 and the inner body portion 190 each formed as a single unitary body portion. The coupling element 260 can then be removed using any method (e.g., by cutting at the dashed line shown in FIG. 10 ) so that the inner body portion 190 is contained within the outer body portion 176 and can move within the outer body portion 176 as described herein.

[0067] The embodiments of the present disclosure provide various technical and commercial advantages, and example embodiments are described herein. The vibration damping system 120 reduces vibration of the nozzle or blade with a simple configuration and does not add significant extra mass to the nozzle 112 or blade 114. The vibration damping system 120 does not increase the centrifugal forces on the proximal end 130 of the nozzle 112 or the distal end 132 of the blade 114, and does not require changes to the configuration of the nozzle 112 or blade 114. The nested damper pins 174 allow the inner body portion 190 to continue its friction-based vibration damping movement (by interaction of the inner surface 162 of the body opening 160 with the arms 194) using the stacked damper pins, even if the multiple outer body portions 176 are bound at the end faces 184, 186, for example, by the overall weight of the damper pins and / or centrifugal forces.

[0068] Approximate language used throughout the specification and claims can be applied to modify any quantitative expression that can be reasonably varied without causing a change in the basic function involved. Thus, values ​​modified by one or more terms (such as "approximately", "about", and "sufficiently") are not limited to the exact value specified. In at least some instances, approximate language may correspond to the precision of the instrument for measuring the value. Range limitations can be combined and / or substituted herein and throughout the specification and claims. Unless the context or language indicates otherwise, such ranges are identified and include all subranges encompassed therein. "About" applied to a particular value in a range applies to both ends of the range and can indicate + / - 10% of the stated value, unless otherwise dependent on the precision of the instrument for measuring the value.

[0069] The corresponding structures, materials, acts, and equivalents of all means-plus-function or step-plus-function elements in the claims are intended to encompass any structures, materials, or acts for performing that function in combination with other specifically claimed claim elements. The description of the present disclosure has been presented for purposes of illustration and description, and is not intended to be all inclusive or to limit the disclosure to the disclosed form. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the disclosure. The present embodiment has been chosen and described in order to best explain the principles and practical applications of the disclosure and to enable others skilled in the art to understand the disclosure and to devise various modified embodiments as may be suitable for particular uses. [Explanation of symbols]

[0070] 90 Turbomachinery 100 Systems 102 Compressor 104 Combustor 105 Combustion Zone 106 Fuel nozzle section 108 Turbine 110 Rotor 112 Nozzle 114 Blade 115 Stationary nozzle section 116 Rotor Wheel 120 Vibration Damping System 124 Casing 128 Main body 130 Proximal end 132 Tip 134 Airfoil 136 Outer end wall 138 Inner end wall 140 Dovetail 142 Shank 146 Platform 154 Leading Edge 156 Trailing edge 158 Tip 160 Main body opening 162 Inside 164 Components 166 Components 174 Damper pin 176 Outer body part 178 Inner opening 180 Side opening 182 Exterior 184 End face 186 End face 192 parts 194 Arm 195 Outer edge 200 Exterior 202 Bulbous part 204 Concave 210 Third Part 212 Second opening 214 Cylindrical elements 250 Retaining damper pin 252 End 260 Joint Elements

Claims

1. 1. A damper pin (174) for a vibration damping system (120) for a turbine nozzle (112) or a turbine blade (114), the damper pin (174) comprising: an outer body portion (176) having an inner opening (178) defined therein and a plurality of side openings (180) extending from the inner opening (178) through an outer surface (182) of the outer body portion (176); an inner body portion (190) received within the inner opening (178) of the outer body portion (176) and movable within the inner opening, the inner body portion (190) including a first portion (192) including a plurality of arms (194), each arm (194) extending through a respective one of the plurality of side openings (180) of the outer body portion (176); Including the damper pin.

2. 2. The damper pin (174) of claim 1, wherein the plurality of arms (194) define an outer dimension (OD2) that is greater than an outer dimension (OD1) of the outer body portion (176), the outer dimension (OD2) configured to engage an inner surface (162) of a body opening (160) of the turbine nozzle (112) or turbine blade (114) in which the damper pin (174) is disposed.

3. The inner body portion (190) further comprises: a second portion (196) having an outer surface (200) configured to frictionally engage a first opening (198) of the inner opening (178) of the outer body portion (176); a third portion (210) extending through and spaced from the second opening portion (212) of the inner opening (178) of the outer body portion (176); Including, 2. The damper pin (174) of claim 1, wherein a first portion (192) of the inner body portion (190) including the plurality of arms (194) is disposed between a second portion (196) and a third portion (210) of the inner body portion (190).

4. 4. The damper pin (174) of claim 3, wherein an outer surface (200) of the second portion (196) of the inner body portion (190) has a bulbous portion (202) and a first opening (198) of the inner opening (178) of the outer body portion (176) has a concave surface (204) complementary to the bulbous portion (202).

5. 4. The damper pin (174) of claim 3, wherein a second opening portion (212) of the inner opening (178) of the outer body portion (176) is spaced from a third portion (210) of the inner body portion (190) by a distance that defines an extent of lateral tilt of the inner body portion (190) within the outer body portion (176).

6. 4. The damper pin (174) of claim 3, wherein an outer surface (200) of the inner body portion (190) and a first opening portion (198) of the inner opening (178) of the outer body portion (176) frictionally engage with the plurality of arms (194) engaging an inner surface (162) of a body opening (160) of the turbine nozzle (112) or turbine blade (114).

7. 4. The damper pin (174) of claim 3, wherein the outer body portion (176) further includes a first end face (184) and an opposing second end face (186), the inner opening (178) of the outer body portion (176) extending through the first end face (184) and the second end face (186), and the third portion (210) of the inner body portion (190) extending from the inner opening (178) through one of the first and second end faces (184, 186).

8. 8. The damper pin (174) of claim 7, wherein a first end surface (184) of the outer body portion (176) is at least partially concave and a second end surface (186) of the outer body portion (176) is at least partially convex whereby the first end surface (184) and the second end surface (186) of an adjacent damper pin (174) frictionally engage.

9. 2. The damper pin (174) of claim 1, wherein the outer body portion (176) and the inner body portion (190) are additively manufactured, and the outer body portion (176) and the inner body portion (190) are integrally coupled and secured to one another by a removable coupling element (260) prior to separation after the additive manufacturing.

10. A vibration damping system (120) for a turbine nozzle (112) or a turbine blade (114), the vibration damping system (120) comprising: A plurality of stacked damper pins (174), each damper pin (174) having: an outer body portion (176) having an inner opening (178) defined therein and a plurality of side openings (180) extending from the inner opening (178) through an outer surface (182) of the outer body portion (176); an inner body portion (190) received within the inner opening (178) of the outer body portion (176) and movable within the inner opening, the inner body portion (190) including a first portion (192) including a plurality of arms (194), each arm (194) extending through a respective one of the plurality of side openings (180) of the outer body portion (176); a vibration damping system (120) comprising:

11. 11. The vibration damping system (120) of claim 10, wherein the plurality of arms (194) define an outer dimension (OD2) greater than an outer dimension (OD1) of the outer body portion (176), the outer dimension (OD2) configured to engage an inner surface (162) of a body opening (160) of the turbine nozzle (112) or turbine blade (114) in which the damper pin (174) is disposed.

12. The inner body portion (190) further comprises: a second portion (196) having an outer surface (200) configured to frictionally engage a first opening (198) of the inner opening (178) of the outer body portion (176); a third portion (210) extending through and spaced from the second opening portion (212) of the inner opening (178) of the outer body portion (176); Including, 11. The vibration damping system (120) of claim 10, wherein a first portion (192) of the inner body portion (190) including the plurality of arms (194) is disposed between a second portion (196) and a third portion (210) of the inner body portion (190).

13. 13. The vibration damping system of claim 12, wherein an outer surface (200) of the second portion (196) of the inner body portion (190) has a bulbous portion (202) and a first opening (198) of the inner opening (178) of the outer body portion (176) has a concave surface (204) complementary to the bulbous portion (202).

14. 13. The vibration damping system of claim 12, wherein a second opening portion of the inner opening of the outer body portion is spaced from a third portion of the inner body portion by a distance that defines an extent of lateral tilt of the inner body portion within the outer body portion.

15. 13. The vibration damping system of claim 12, wherein an outer surface of the inner body portion and a first opening portion of the inner opening of the outer body portion are frictionally engaged with each other under the influence of the plurality of arms engaging an inner surface of a body opening of the turbine nozzle or turbine blade.

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