Improved rotor blade seal structure

Abstract

The invention is entitled Improved Rotor Blade Seal Structure. The invention provides a rotor blade (26, 30). The rotor blade (26, 30) includes a main body (35) having a shank (38), an airfoil (36) extending radially outward from the shank (38), and a platform (42). The main body (35) includes a pressure side impingement surface (56) and a suction side impingement surface (58). A slot (70) is defined within each of the pressure side impingement surface (56) and the suction side impingement surface (58). The slot (70) of the pressure side impingement surface (56) and the slot (70) of the suction side impingement surface (58) each include an upstream end portion (74) defining an end (72) and a main body portion (90) extending from the upstream end portion (74). The upstream end portion (74) tapers from the end (72) to the main body portion (90). The main body portion (90) further includes a retention wall (78) covering a portion of the end (72) and defining an opening (80). The retention wall (78) further includes an interior retention surface (102). The retention wall (78) defines an offset (150, 152) from the opening (80).

Description

Technical Field

[0001] This disclosure relates generally to rotor blades for turbines, and more specifically to improved rotor blade sealing structures. Background Technology

[0002] Turbines are used in a variety of industries and applications for energy transfer purposes. For example, a gas turbine engine typically includes a compressor section, a combustion section, a turbine section, and an exhaust section. The compressor section gradually increases the pressure of the working fluid entering the gas turbine engine and supplies this compressed working fluid to the combustion section. The compressed working fluid and fuel (e.g., natural gas) mix in the combustion section and are burned in the combustion chamber to produce high-pressure, high-temperature combustion gases. The combustion gases flow from the combustion section into the turbine section, where they expand to do work. For example, the expansion of the combustion gases in the turbine section can cause a rotor shaft connected to, for example, a generator to rotate to generate electricity. The combustion gases then exit the gas turbine via the exhaust section.

[0003] The compressor and turbine sections typically consist of multiple rotor blades arranged in multiple stages. During engine operation, fluctuations in the flow rate of the compressed working fluid, hot combustion gas, or steam can cause leakage within the rotor blade assembly, resulting in an overall loss of engine performance. For example, hot combustion gas from the turbine section can leak into the blade shank or root cavity, causing unwanted rotor disk heating.

[0004] In order to improve overall engine performance by minimizing leakage in the rotor blades, seals are typically provided between the rotor blades on the rotor disc to prevent escaping working fluid or combustion gases from passing through.

[0005] However, there is a desire to improve overall seal performance. For example, one problem with many known rotor blade seals is that they are cumbersome to install and require additional hardware, such as one or more locking plates, to hold them within the rotor blade shank. Failure of this additional hardware can cause the seal to dislodge from its slot and / or fail prematurely.

[0006] Therefore, there is a need in the art for improved rotor blade seal retention designs. Specifically, damper designs that provide improved seal retention without requiring additional hardware would be advantageous. Summary of the Invention

[0007] The aspects and advantages of the rotor blades, rotor blade assemblies and turbines according to this disclosure will be set forth in part in the following description, or will be apparent from the description, or may be learned by practice of the art.

[0008] According to one embodiment, a rotor blade assembly for a turbine is provided. The rotor blade assembly includes a rotor disk and a first rotor blade and a second rotor blade mounted adjacent to each other on the rotor disk. Each of the first and second rotor blades includes a body having a shank, an airfoil extending radially outward from the shank, and a platform. The body includes a pressure-side impact surface and a suction-side impact surface. A slot is defined within each of the pressure-side and suction-side impact surfaces. The slot in the pressure-side impact surface and the slot in the suction-side impact surface each include an upstream end portion defining an end and a body portion extending from the upstream end portion. The upstream end portion tapers towards the body portion. The body also includes a retaining wall covering a portion of the end and defining an opening. The retaining wall also includes an internal retaining surface. The retaining wall defines an offset from the opening. The slot in the pressure-side impact surface of the first rotor blade and the slot in the suction-side impact surface of the second rotor blade define a channel.

[0009] According to another embodiment, a rotor blade is provided. The rotor blade includes a body having a shank, an airfoil extending radially outward from the shank, and a platform. The body includes a pressure-side impact surface and a suction-side impact surface. A slot is defined within each of the pressure-side and suction-side impact surfaces. The slot on the pressure-side impact surface and the slot on the suction-side impact surface each include an upstream end portion defining an end and a body portion extending from the upstream end portion. The upstream end portion tapers towards the body portion. The body also includes a retaining wall covering a portion of the end and defining an opening. The retaining wall also includes an internal retaining surface. The retaining wall defines an offset from the opening.

[0010] According to another embodiment, a turbine is provided. The turbine includes a compressor section, a combustor section, and a turbine section. The turbine also includes a plurality of rotor blades disposed in at least one of the compressor section or the turbine section. Each of the plurality of rotor blades includes a body having a shank, an airfoil extending radially outward from the shank, and a platform. The body includes a pressure-side impact surface and a suction-side impact surface. A slot is defined within each of the pressure-side impact surface and the suction-side impact surface. The slot of the pressure-side impact surface and the slot of the suction-side impact surface each include an upstream end portion defining an end and a body portion extending from the upstream end portion. The upstream end portion tapers towards the body portion from the end. The body also includes a retaining wall covering a portion of the end and defining an opening. The retaining wall also includes an internal retaining surface. The retaining wall defines an offset from the opening.

[0011] These and other features, aspects, and advantages of the rotor blades, rotor blade assemblies, and turbines of the present invention will become more readily understood with reference to the following description and the appended claims. The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments of the technology and, together with the description, serve to explain the principles of the technology. Attached Figure Description

[0012] This specification sets forth, with reference to the accompanying drawings, a complete and feasible disclosure of the present invention concerning shaft rotor blades, rotor blade assemblies, and turbines, which is relevant to those skilled in the art, including the best mode for manufacturing and using the systems and methods of the invention, wherein:

[0013] Figure 1 A schematic diagram of a turbine according to an embodiment of the present disclosure is shown;

[0014] Figure 2 A perspective view of the pressure side of a rotor blade according to an embodiment of the present disclosure is shown;

[0015] Figure 3 A suction-side perspective view of a rotor blade according to an embodiment of the present disclosure is shown;

[0016] Figure 4 This is an enlarged perspective view of the pressure side impact surface of a rotor blade with a seal provided in its slot, according to an embodiment of the present disclosure.

[0017] Figure 5 This is an enlarged side view of the impact surface of a rotor blade according to an embodiment of this disclosure;

[0018] Figure 6 This is a side view of a rotor blade assembly having two adjacent rotor blades according to an embodiment of the present disclosure;

[0019] Figure 7 This is an enlarged bottom view of a rotor blade assembly having adjacent rotor blades according to an embodiment of this disclosure;

[0020] Figure 8 A side view of the slot opening of two adjacent rotor blades according to an embodiment of the present disclosure is shown; and

[0021] Figure 9 This is a slotted cross-sectional view along the body of two adjacent rotor blades according to an embodiment of this disclosure. Detailed Implementation

[0022] Reference will now be made in detail to embodiments of the rotor blades, rotor blade assemblies, and turbines of the present invention, one or more examples of which are illustrated in the accompanying drawings. Each example is provided by way of explanation of the inventive technique, and not as a limitation thereof. Indeed, it will be apparent to those skilled in the art that various modifications and variations may be made to the inventive technique without departing from the scope or spirit of the technique protected by the claims. For example, a feature shown or described as part of one embodiment may be used in another embodiment to produce yet another embodiment. Therefore, this disclosure is intended to cover these modifications and variations that fall within the scope of the appended claims and their equivalents.

[0023] The detailed description uses numbers and letters to refer to feature structures in the drawings. Similar or analogous names in the drawings and description have been used to refer to similar or analogous parts of the invention. As used herein, the terms "first," "second," and "third" are used interchangeably to distinguish one part from another and are not intended to indicate the location or importance of the various parts.

[0024] As used herein, the terms “upstream” (or “upward”) and “downstream” (or “downward”) refer to the relative directions of fluid flow within a fluid pathway. For example, “upstream” refers to the direction from which fluid flows, and “downstream” refers to the direction from which fluid flows.

[0025] The term “radial” refers to a relative direction that is substantially perpendicular to the axial centerline of a particular component; the term “axial” refers to a relative direction that is substantially parallel to and / or coaxially aligned with the axial centerline of a particular component; and the term “circumferential” refers to a relative direction that extends around the axial centerline of a particular component.

[0026] Approximate terms, such as “generally” or “about,” include values ​​that are greater than or less than ten percent of the specified value. When used in the context of angles or directions, such terms include values ​​that are greater than or less than five degrees of the angle or direction. For example, “generally vertical” includes directions that are within five degrees of vertical in any direction (e.g., clockwise or counterclockwise).

[0027] Now refer to the attached diagram, Figure 1 A schematic diagram of one embodiment of a turbine is shown, which in the illustrated embodiment is a gas turbine 10. Although industrial or land-based gas turbines are shown and described herein, this disclosure is not limited to industrial and / or land-based gas turbines unless otherwise specified in the claims. For example, rotor blades and rotor blade assemblies as described herein can be used in any type of turbine, including but not limited to steam turbines, gas turbines for aircraft, or gas turbines for marine applications.

[0028] As shown in the figure, the gas turbine 10 generally includes an inlet section 12, a compressor section 14 disposed downstream of the inlet section 12, a plurality of burners (not shown) disposed in a burner section 16 disposed downstream of the compressor section 14, a turbine section 18 disposed downstream of the burner section 16, and an exhaust section 20 disposed downstream of the turbine section 18. Additionally, the gas turbine 10 may include one or more shafts 22 connecting the compressor section 14 and the turbine section 18.

[0029] The compressor section 14 may generally include a plurality of rotor disks 24 (one of which is shown) and a plurality of rotor blades 26 extending radially outward from each rotor disk 24 and connected to each rotor disk. Each rotor disk 24 may then be coupled to or form part of a shaft 22 extending through the compressor section 14.

[0030] Turbine section 18 may generally include a plurality of rotor disks 28 (one of which is shown) and a plurality of rotor blades 30 extending radially outward from each rotor disk 28 and interconnected to each rotor disk. Each rotor disk 28 may then be coupled to or form a portion of a shaft 22 extending through turbine section 18. Turbine section 18 also includes an outer housing 31 that circumferentially surrounds a portion of shaft 22 and rotor blades 30, thereby at least partially defining a hot gas path 32 through turbine section 18.

[0031] During operation, a working fluid, such as air, flows through inlet section 12 and into compressor section 14, where the air is gradually compressed to supply pressurized air to the combustors in combustion section 16. The pressurized air mixes with fuel and burns in each combustor to produce combustion gases 34. Combustion gases 34 flow from combustor section 16 through hot gas path 32 and into turbine section 18, where energy (kinetic and / or thermal energy) is transferred from combustion gases 34 to rotor blades 30, causing shaft 22 to rotate. This mechanical rotational energy can then be used to power compressor section 14 and / or generate electricity. The combustion gases 34 exiting turbine section 18 can then be discharged from gas turbine 10 via exhaust section 20.

[0032] Figure 2 and Figure 3 An embodiment of a rotor blade according to the present disclosure is shown. In the illustrated embodiment, the rotor blade is a turbine blade or a moving blade 30, but in an alternative embodiment, the rotor blade may be a compressor blade or a moving blade 26.

[0033] The rotor blade 30 may include a body 35, which includes an airfoil 36 and a shank 38. The airfoil 36 may extend radially outward from and be positioned within the shank 38. The shank 38 may include a root or dovetail 40 that may be attached to the rotor disk 28 to facilitate rotation of the rotor blade 30.

[0034] The airfoil 36 may have a generally aerodynamic profile. For example, the airfoil 36 may have an outer surface that defines a pressure side and a suction side, each extending between a leading edge and a trailing edge. The outer surface of the shank 38 may include a pressure side, a suction side, a leading edge surface, and a trailing edge surface.

[0035] The body 35 may also include a platform 42 generally surrounding the body 35. A typical platform may be located at the junction or transition between the airfoil 36 and the shank 38, and may extend outward in generally axial and tangential directions, as shown. In the turbine section 18, the platform 42 generally serves as a radially inward flow boundary for the combustion gases 34 flowing through the hot gas path 32. The platform 42 may include a leading edge surface 52 axially spaced from the trailing edge surface 54. The leading edge surface 52 is located in the combustion gas flow 34, and the trailing edge surface 54 is located downstream of the leading edge surface 52. Furthermore, the platform 42 may include a pressure-side impact surface 56 circumferentially spaced from the suction-side impact surface 58.

[0036] In some implementation schemes, such as Figure 2 and Figure 3 As shown, the pressure-side impact surface 56 and / or the suction-side impact surface 58 may be generally planar surfaces (which can typically be planar or inclined). In other embodiments, the pressure-side impact surface 56 and / or the suction-side impact surface 58, or at least a portion thereof, may be curved. For example, in Figure 4 In the illustrated embodiment, the pressure-side impact surface 56 or the suction-side impact surface 58 may be bent relative to the axial direction, radial direction, and / or tangential direction.

[0037] Figure 6 A perspective view of a pair of circumferentially adjacent rotor blades 30′, 30″ in a rotor blade assembly 200 is shown. As shown, when the rotor blades 30 are positioned such that the pressure-side impact surface 56 of the rotor blade 30 faces the suction-side impact surface 58 of the adjacent rotor blade 30. As described above, a plurality of rotor blades 30 may be disposed on each of one or more rotor disks 28 and may extend radially outward from each rotor disk. The rotor blades 30 disposed on the rotor disks 28 may be assembled in a circumferential array such that when the rotor blades 30 are assembled such that the pressure-side impact surface 56 of each rotor blade 30 faces the suction-side impact surface 58 of each adjacent rotor blade 30. In some embodiments, the pressure-side impact surface 56 of each rotor blade 30 and the suction-side impact surface 58 of each adjacent rotor blade 30 may define a gap 60.

[0038] See you again Figure 2 and Figure 3The pressure-side impact surface 56 and suction-side impact surface 58 of the body 35 are shown. The body 35 may include one or more slots 70. The slots 70 may be defined within the pressure-side impact surface 56 and / or the suction-side impact surface 58 of the body 35. The slot 70 may include an upstream end portion 74 defining a slot end or end 72. The slot 70 may extend from the slot end 72 to a closed downstream end 76. The slot 70 may be a continuous groove defined along the pressure-side impact surface 56 and / or the suction-side impact surface 58. In some embodiments, the slot 70 may be circumferentially defined in each of the pressure-side impact surface 56 and the suction-side impact surface 58 of the body 35.

[0039] The slot 70 includes a body portion 90 extending directly from an upstream end portion 74 to a closed downstream end portion 76. In some embodiments, the body portion 90 of the slot 70 may be connected to the upstream end portion 74. The body portion 90 of the slot 70 may include a leading edge segment 92, a plateau segment 94, and a trailing edge segment 96. The leading edge segment 92 may be defined along a leading edge face 52, the plateau segment 94 may be defined along a plateau 42, and the trailing edge segment 96 may be defined along a trailing edge face 56. As used herein, terms such as “defined along” and their cognates may mean “substantially parallel to” or “generally in a straight line with”. In other embodiments, the leading edge segment 92 and the trailing edge segment 96 of the slot 70 may be generally radially oriented relative to the axial centerline of the gas turbine 10. Similarly, the plateau segment 92 of the slot 70 may be generally axially oriented.

[0040] In some embodiments, the leading edge segment 92 may be directly connected to and associated with the platform segment 94. Similarly, the platform segment 94 may be directly connected to and associated with the trailing edge segment 96. The slot 70 may taper from the end 72 toward the body portion 90. More specifically, the slot 70 may taper from the end 72 toward the leading edge segment 92 of the body portion 90.

[0041] like Figure 4 As shown, the main body portion 90 of the slot 70 may be sized to securely contain a portion of the seal 84 therein, i.e., the main body portion 90 may be sized to prevent the seal 84 from slipping out of the slot 70 during operation of the gas turbine 10. The seal 84 may also include a first end 86 and a second end 88, and may extend between the two. The seal 84 may be sized to at least partially seal into the slot 70.

[0042] In various embodiments, the slot 70 may include one or more fractured walls (not shown) along its length, such as a leading edge 92, a plateau segment 94, and a trailing edge 96. In such embodiments, one or more walls of the slot may be recessed, thereby exposing at least partially a large portion of the seal 84 therein. Thus, in some embodiments, the slot 70 may be discontinuous from the upstream end portion 74 to the closed downstream end 76.

[0043] See now Figure 5 An enlarged side view of a portion of the impact surface 55 of the display slot 70 is shown. The impact surface 55 may be a pressure-side impact surface 56 or a suction-side impact surface 58. Figure 5 As shown, the end 72 of the slot 70 may also include a retaining wall 78 that covers a portion of the end 72 and defines the slot opening 80. In many embodiments, the slot opening 80 is used to slidably receive at least a portion of the seal 84 into the slot 70 (e.g., Figure 4 As shown). Figure 5 As shown, the slot 70 may further include a first slot wall 104 and a second slot wall 106 separated from each other. In some embodiments, a retaining wall 78 may extend outwardly from the second slot wall 106 and define a first opening portion 120 of the opening 80 at an end 72. Additionally, the first slot wall 104 may extend from a closed downstream end 76 to the end 72 and partially define a second opening portion 122 of the opening 80 at the end 72. The first slot wall 104 may be directly connected to and associated with the second opening portion 122.

[0044] In some implementation schemes, such as Figure 7 As shown, the first slot wall 104 may extend through the inner retaining surface 102 of the retaining wall 78. The second slot wall 106 may extend from the closed downstream end 76 to the inner retaining surface 102. In some embodiments, the first opening portion 120 and the second opening portion 122 may be parallel to each other in the circumferential direction at the end 72.

[0045] In some implementation schemes such as Figures 2 to 5 In the illustrated embodiment, the first slot wall 104 and the second slot wall 106 may be substantially parallel to each other along the main body portion 90 of the slot 70. Additionally, the first slot wall 104 and the second slot wall 106 may taper away from each other along the upstream end portion 74. In some embodiments, both the first slot wall 104 and the second slot wall 106 may taper away from each other from the main body portion 90 toward the inner retaining surface 102 of the retaining wall 78.

[0046] like Figure 5As shown, retaining wall 78 may extend from second wall 106 and cover a portion of end 72 to define a first opening portion 120 of opening 80. The first opening portion 120 may be substantially curved or arcuate to provide a smooth surface for the seal 84 to slide against during installation into slot 70. The first opening portion 120 may extend from end 72 to inner retaining surface 102.

[0047] When two or more blades 30 are arranged adjacent to each other on the rotor disk 24, such as in Figures 6 to 9 As shown and discussed herein, the slot 70 of the pressure-side impact surface 56 of each rotor blade 30 is aligned with the slot 70 of the suction-side impact surface 58 of the adjacent rotor blade 30 to define a channel 82. Rotor blades 30 arranged adjacent to each other may include rotor blades 30 directly adjacent to each other on the rotor disk 24 and / or rotor blades 30 in direct contact with each other (e.g., blades 30′ and 30″). A gap 60 may be partially provided between the pressure-side impact surface 56 and the suction-side impact surface 58 of two adjacent blades 30 on the rotor disk 24. In some embodiments, the gap 60 may be partially provided between the slot 70 of the pressure-side impact surface 56 of each rotor blade 30 and the slot 70 of the suction-side impact surface 58 of the adjacent rotor blade 30 on the rotor disk 24.

[0048] In many embodiments, channel 82 may be used to slidably receive and accommodate seal 84 therein. Seal 84 may extend from slot 70 of pressure-side impact surface 56 to slot 70 of suction-side impact surface 58 and cover gap 60. In some embodiments, seal 84 prevents unwanted hot gas from turbine section 18 from leaking into the body 35 of blade 30. Alternatively or in addition, in many embodiments, seal 84 prevents compressed cooling air from compressor section 14 from leaking out of handle 38 and into turbine section 18.

[0049] like Figures 7 to 9 As shown, the rotor blade assembly 200 includes a first slot 70' and a second slot 70'' defined in adjacent rotor blades 30'' and 30'', respectively. When positioned adjacent to each other on the rotor disk 28, the first slot 70' of rotor blade 30'' can be aligned with the second slot 70'' of the adjacent rotor blade 30'. The first slot 70' can be defined in the pressure-side impact surface 56 or the suction-side impact surface 58 of the rotor blade 30. Similarly, the second slot 70'' can be defined in the corresponding suction-side impact surface 58 or pressure-side impact surface 58 of the adjacent rotor blade 30. For example, if the first slot 70' is defined in the pressure-side impact surface 56 of the rotor blade 30, then the second slot 70'' can be defined in the suction-side impact surface 58 of the adjacent rotor blade, or vice versa.

[0050] See now Figure 7The figure shows a perspective view of circumferentially adjacent rotor blades 30′ and 30″ in the rotor blade assembly 200. As shown, when the rotor blade 30 is positioned such that the first slot 70′ defined in the pressure-side impact surface 56 of the rotor blade 30 faces the second slot 70″ defined in the suction-side impact surface 58 of the adjacent rotor blade 30. In implementation, when... Figure 7 When positioned, the opening 80 of the first slot 70′ and the opening 80 of the second slot 70″ are used to slidably receive the seal 84 therein.

[0051] like Figure 4 As shown, the first end 86 of the seal 84 enters the opening 80 and is received by the closed downstream end 76 through the body portion 90 of the slots 70′, 70″. As the second end 88 of the seal 84 begins to pass through the opening 80, pressure from the body portion 90 on the first end 86 of the seal 84 forces the second end 88 to move upward along the second slot wall 106 and abut against the inner retaining surface 102 at the upstream end portion 74. Once installed, the first end 86 of the seal 84 is in contact with the closed downstream end 76 of the first slot 70′ and the second slot 70″, and the second end 88 of the seal 84 is in contact with the inner retaining surface 102.

[0052] In some embodiments, the length of the seal 84 may be shorter than the total length of the slots 70′, 70″ to allow for thermal expansion of the seal 84. The seal 84 extends through the entire channel 82 and can block the gap 60 between adjacent rotor blades 30′, 30″. In addition, the internal retaining surfaces 102 of the first slot 70′ and the second slot 70″ prevent the seal 84 from exiting the slots 70′, 70″.

[0053] Figure 8 The opening 80 of the first slot 70' and the second slot 70'' of adjacent rotor blades 30' and 30''' is shown. Figure 8 As shown, retaining wall 78 may define a translational offset 150 from slot opening 80. More specifically, retaining wall 78 may define a translational offset 150 between the first opening portion 120 of slot 70 and the second wall 106.

[0054] In some embodiments, the translation offset 150 may be up to about 1.5 inches. In other embodiments, the translation offset 150 may be up to about 1.0 inch. In many embodiments, the translation offset 150 may be up to about 0.75 inches. In other embodiments, the translation offset 150 may be up to about 0.5 inches. In various embodiments, the translation offset 150 may be up to about 0.4 inches. In many embodiments, the translation offset 150 may be up to about 0.3 inches. In some embodiments, the translation offset 150 may be up to about 0.2 inches. In other embodiments, the translation offset 150 may be up to about 0.1 inches.

[0055] In various embodiments, the translation offset 150 may be between approximately 0.75 inches and 1 inch. In many embodiments, the translation offset 150 may be between approximately 0.1 inches and 0.75 inches. In various embodiments, the translation offset 150 may be between approximately 0.1 inches and 0.5 inches. In other embodiments, the translation offset 150 may be between approximately 0.1 inches and 0.4 inches. In many embodiments, the translation offset 150 may be between approximately 0.1 inches and 0.3 inches. In other embodiments, the translation offset 150 may be between approximately 0.1 inches and 0.2 inches.

[0056] As an alternative to or in addition to translational offset 150, retaining wall 78 may also include rotational offset 152. Specifically, the first opening portion 120 may include both translational offset 150 and rotational offset 152 from the second slot wall 106. Rotational offset 152 may be defined at an angle relative to the second slot wall 106. In some embodiments, the translational offset 150 of the first slot 70′ may vary along the first slot depth 110 due to translational offset 152. Similarly, the translational offset 150 of the second slot 70″ may vary along the second slot depth 112 due to rotational offset 152.

[0057] In some embodiments, the second opening portion 122 may further include a rotational offset 152 from the second slot wall 106. In various embodiments, the rotational offset 152 of the first opening portion 120 of the slot 70 may differ from the rotational offset 152 of the second opening portion 122 of the same slot 70. For example... Figure 8 As shown, the first slot 70′ and the second slot 70″ may each include different translational offsets 150 and rotational offsets 152. For example, the first slot 70′ may have a first opening portion 120 and a second opening portion 122, which have the same rotational offset 152, i.e., they are substantially parallel, while the second slot 70″ may have a first opening portion 120 and a second opening portion 122, which each have different rotational offsets 152.

[0058] In many implementation schemes such as Figure 8 In the illustrated embodiment, the first opening portion 120 of the first slot 70′ and the first opening portion 120 of the second slot 70″ may have the same rotational offset 152. In addition, the second opening portion 122 of the first slot 70′ and the second opening portion 122 of the second slot 70″ may each have different rotational offsets 152.

[0059] In some embodiments, the rotation offset 152 may be up to about 60 degrees. In other embodiments, the rotation offset 152 may be up to about 50 degrees. In many embodiments, the rotation offset 152 may be up to about 40 degrees. In some embodiments, the rotation offset 152 may be up to about 30 degrees. In various embodiments, the rotation offset 152 may be up to about 20 degrees. In many embodiments, the rotation offset 152 may be up to about 10 degrees. In other embodiments, the rotation offset 152 may be up to about 5 degrees.

[0060] In other embodiments, the rotation offset 152 may be between about 5 degrees and about 60 degrees. In various embodiments, the rotation offset 152 may be between about 5 degrees and about 50 degrees. In many embodiments, the rotation offset 152 may be between about 5 degrees and about 40 degrees. In various embodiments, the rotation offset 152 may be between about 5 degrees and about 30 degrees. In other embodiments, the rotation offset 152 may be between about 5 degrees and about 20 degrees. In many embodiments, the rotation offset 152 may be between about 5 degrees and about 10 degrees. In many embodiments, the rotation offset 152 may be between about zero degrees and about 5 degrees.

[0061] like Figure 8 As shown, the first slot 70′ may include a first slot depth 110, and the second slot 70″ may include a second slot depth 112. Both the first slot depth 110 and the second slot depth 112 may vary from end 72 toward the closed downstream end 76. For example, the first slot depth 110 or the second slot depth 112 may vary from end 72 of the body portion 90 of the slot 70 toward the forward edge 92, i.e., become larger or smaller. Generally, the sum of the lengths of the first slot depth 110, the second slot depth 112, and the gap 60 is approximately equal to the width of the seal 84 along the entire length of the channel 82.

[0062] In various embodiments, the seal 84 may be slightly smaller than the slots 70′, 70″, and may have space for thermal expansion within the slots 70′, 70″. Additionally, the seal 84 may be sized to allow for manufacturing variations. For example, in many embodiments, the width of the seal 84 may be between about 70% and about 100% of the width of the channel 82 to allow for both manufacturing variations and thermal expansion within the slot 70. Figure 8In the illustrated embodiment, the first slot depth 110 is greater than and / or different from the second slot depth 112 at the opening 80; however, in other embodiments, the first slot depth 110 and the second slot depth 112 may be approximately equal at the opening 80.

[0063] See now Figure 9 An enlarged cross-sectional view of the first slot 70′ and the second slot 70″ along the main body portion 90 of the slots 70′ and 70″ is shown. For example, Figure 9 Platform section 94 of the main body 90 of the narrow slots 70′ and 70″. Alternatively, [location to be selected]. Figure 9 A cross-section of the slots 70′ and 70″ along the trailing edge segment 96 can be shown. (e.g.) Figure 9 As shown, the first depth 110 of the main body portion 90 along the slots 70′ and 70″ may be shorter than the second slot depth 112.

[0064] This written description uses examples to disclose the invention, including the best mode, and also enables any person skilled in the art to practice the invention, including making and using any device or system and performing any combined methods. The patentable scope of the invention is defined by the claims and may include other examples that would occur to a person skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that are not different from the literal language of the claims, or if they include equivalent structural elements that are not substantially different from the literal language of the claims.

Claims

1. A rotor blade (26, 28) for a turbine, said rotor blade (26, 28) comprising: The main body (35) has a handle (38), an airfoil (36) extending radially outward from the handle (38) and a platform (42), the main body (35) including a pressure-side impact surface (56) and a suction-side impact surface (58); A slot (70) is defined within each of the pressure-side impact surface (56) and the suction-side impact surface (58), wherein each of the slots (70) on the pressure-side impact surface (56) and the suction-side impact surface (58) comprises: First slot wall; The second slot wall is opposite to the first slot wall; The upstream end portion (74) has an end portion (72) that defines an axially extending surface; An opening, which is at least partially defined by the first slot wall on the axially extending surface; A main body portion (90) extending from the upstream end portion (74), the upstream end portion (74) tapering towards the main body portion (90) from the end portion (72), the upstream end portion (74) including a retaining wall (78) extending from the second slot wall to a boundary, the retaining wall partially defining the opening (80), the retaining wall (78) including an internal retaining surface (102), the boundary of the retaining wall (78) defining a rotational offset and translational offset relative to the second slot wall.

2. The rotor blades (26, 28) according to claim 1, wherein the rotor blades (26, 28) are first rotor blades; and wherein when mounted adjacent to each other on a rotor disk, the slot (70) of the pressure-side impact surface (56) of the first rotor blade and the slot (70) of the suction-side impact surface (58) of the second rotor blade define a channel (82).

3. The rotor blade (26, 28) according to claim 2, wherein the main body portion (90) extends between the upstream end portion (74) and the closed downstream end portion (76).

4. The rotor blades (26, 28) according to claim 1, wherein the translational offset (150) is at most 1.5 inches.

5. The rotor blades (26, 28) according to claim 1, wherein the rotational offset (152) is between 5 degrees and 60 degrees.

6. The rotor blades (26, 28) according to claim 3 further include a seal at least partially located within the body portion (90), wherein the seal is at least partially held in place by the retaining wall (78).

7. The rotor blade (26, 28) according to claim 3, wherein the slot (70) is continuous from the opening (80) to the closed downstream end (76).

8. The rotor blade (26, 28) according to claim 3, wherein the slot (70) of the pressure-side impact surface (56) and the slot (70) of the suction-side impact surface (58) each include a depth circumferentially defined in the respective impact surface; and wherein the depth of each respective slot (70) varies from the upstream end portion (74) to the closed downstream end portion (76).

9. A rotor blade (26, 28) assembly for a turbine, the rotor blade (26, 28) assembly comprising: Rotor disk; A first rotor blade and a second rotor blade are mounted adjacent to each other on the rotor disk. Each of the first rotor blade and the second rotor blade comprises: The main body (35) has a handle (38), an airfoil (36) extending radially outward from the handle (38) and a platform (42), the main body (35) including a pressure-side impact surface (56) and a suction-side impact surface (58); A slot (70) is defined within each of the pressure-side impact surface (56) and the suction-side impact surface (58), wherein each of the slots (70) on the pressure-side impact surface (56) and the suction-side impact surface (58) comprises: First slot wall; The second slot wall is opposite to the first slot wall; The upstream end portion (74) has an end portion (72) that defines an axially extending surface; An opening, which is at least partially defined by the first slot wall on the axially extending surface; A main body portion (90) extending from the upstream end portion (74), the upstream end portion (74) tapering towards the main body portion (90) from the end portion (72), the upstream end portion (74) including a retaining wall (78) extending from the second slot wall to a boundary, the retaining wall partially defining an opening (80) at the end, the retaining wall (78) including an inner retaining surface (102), the boundary of the retaining wall (78) defining a rotational offset and a translational offset relative to the second slot wall, wherein the rotational offset is defined in the plane of the axially extending surface between the second slot wall and the boundary; and, The slot (70) of the pressure-side impact surface (56) of the first rotor blade and the slot (70) of the suction-side impact surface (58) of the second rotor blade define a channel (82).

10. The rotor blade (26, 28) assembly according to claim 9, wherein the main body portion (90) extends between the upstream end portion (74) and the closed downstream end portion (76).

Images