Turbomachinery clearance control using floating seals

Abstract

To provide a sealing arrangement for a gas turbine, and a rotor assembly for a gas turbine.SOLUTION: A sealing arrangement 200 includes a stationary component 202. A first slot 216 is defined between an outer wall 208 and a first inner wall 210. A second slot 218 is defined between the outer wall and a second inner wall 212. A rotating component 204 moves in a circumferential direction relative to the stationary component. The rotating component includes a tip rail. A floating seal 224 is positioned between the stationary component and the rotating component. The floating seal includes an axial member 226 having a first arm 228 extending into the first slot and a second arm 230 extending into the second slot. The floating seal includes a first radial member 232 and a second radial member 234 that extend from the axial member. Multiple magnets 235 are coupled to the stationary component, the rotating component, and the floating seal.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present disclosure relates generally to turbomachine clearances. In particular, the present disclosure relates to controlling clearance between stationary and rotating components in a turbomachine.

Background Art

[0002] Turbomachines are utilized in various industries and applications for energy transfer purposes. For example, gas turbine engines generally include 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) are mixed in the combustion section and burned in a combustion chamber to produce high-pressure and high-temperature combustion gases. The combustion gases flow from the combustion section to the turbine section where they expand to generate work. For example, expansion of the combustion gases in the turbine section can rotate a rotor shaft connected to, for example, a generator to produce electricity. The combustion gases then exit the gas turbine via the exhaust section.

[0003] In certain applications, clearances may exist between components that move relative to one another within a turbomachine. For example, clearances may exist between rotating components and stationary components in rotating machinery such as compressors, turbines, and the like. The clearances may increase or decrease during operation of the rotating machinery due to temperature changes or other factors. As can be appreciated, smaller clearances can improve the performance and efficiency of the compressor or turbine because there is less fluid leakage between the blades and the surrounding shroud. However, smaller clearances also increase the likelihood of rub conditions. Operating conditions also affect the likelihood of rub conditions. For example, the likelihood of rub conditions may increase during transient conditions and decrease during steady-state conditions.

[0004] The sealing assembly may be positioned within the clearance, limiting the amount of flow passing through the clearance by keeping the space between rotating and stationary components small without requiring the components to be in close proximity to each other.

[0005] Known sealing assemblies are most effective when the gas turbine reaches steady-state operating conditions. For example, when both the rotor and stator assemblies reach steady-state operating temperatures, the assemblies thermally expand and fully engage with the sealing assembly. Therefore, improved sealing assemblies for sealing between the rotor and stator assemblies are desired in the art. In particular, a sealing assembly that is effective under all operating conditions of the gas turbine is desirable. [Overview of the Initiative]

[0006] The aspects and advantages of the sealing devices and rotor assemblies described herein are partially described in the following description, or become apparent from the description, or can be learned through the practice of the art.

[0007] According to one embodiment, a sealing device for use in a gas turbine is provided. The sealing device includes a stationary component having an outer wall, a first inner wall, and a second inner wall. The first and second inner walls are spaced apart from the outer wall. A first slot is defined between the outer wall and the first inner wall. A second slot is defined between the outer wall and the second inner wall. The sealing device further includes a rotating component spaced apart from the stationary component. The rotating component moves circumferentially relative to the stationary component. The rotating component includes a tip rail. The sealing device further includes a floating seal positioned between the stationary component and the rotating component. The floating seal includes an axial member having a first arm extending into the first slot and a second arm extending into the second slot. The floating seal includes a first radial member and a second radial member extending from the axial member. The sealing device further includes a plurality of magnets coupled to the stationary component, the rotating component, and the floating seal. Multiple magnets are arranged such that a floating seal is housed between a stationary component and a rotating component.

[0008] According to another embodiment, a rotor assembly for a gas turbine is provided. The rotor assembly includes a plurality of rotor blades extending radially outward from a rotor disk. Each rotor blade in the plurality of rotor blades includes a platform, a tip rail, and an airfoil extending between the platform and the tip rail. The tip rails of each rotor blade in the plurality of rotor blades collectively form a tip rail ring extending circumferentially around the centerline of the gas turbine. The rotor assembly further includes a plurality of shroud blocks extending circumferentially around the centerline of the gas turbine and collectively forming a shroud ring radially spaced apart from the tip rail ring. Each shroud block has an outer wall, a first inner wall, and a second inner wall. The first and second inner walls are radially spaced apart from the outer wall such that a first slot is defined between the outer wall and the first inner wall, and a second slot is defined between the outer wall and the second inner wall. The rotor assembly further includes a floating seal positioned between the tip rail ring and the casing. The floating seal includes an axial member having a first arm extending into a first slot and a second arm extending into a second slot. The floating seal includes a first radial member and a second radial member extending from the axial member. The rotor assembly further includes a shroud block, a tip rail, and a plurality of magnets coupled to the floating seal, the plurality of magnets being arranged such that the floating seal is housed between the tip rail and the shroud block.

[0009] These and other features, aspects, and advantages of the sealing device and rotor assembly will be better understood by referring to the following description and the appended claims. The appended drawings, which are incorporated herein and constitute part of this specification, illustrate embodiments of the art and, together with the description in the specification, help to illustrate the principles of the art.

[0010] A complete and implementable disclosure of the sealing device and rotor assembly, including best modes of fabrication and use of the system and method intended for those skilled in the art, is described herein with reference to the accompanying drawings. [Brief explanation of the drawing]

[0011] [Figure 1] This is a schematic diagram of a turbomachinery according to an embodiment of the present disclosure. [Figure 2] This is a cross-sectional view of a compressor section according to an embodiment of the present disclosure. [Figure 3] This is a cross-sectional view of a turbine section according to an embodiment of the present disclosure. [Figure 4] This is a cross-sectional view of a rotor assembly of a turbine section according to an embodiment of the present disclosure. [Figure 5] This is a perspective view of two adjacent rotor blades according to an embodiment of the present disclosure. [Figure 6] This figure shows a sealing device according to an embodiment of the present disclosure. [Figure 7] This is a cross-sectional view of a rotor assembly of a turbine section having a floating seal used in a clearance, according to an embodiment of the present disclosure. [Modes for carrying out the invention]

[0012] Hereinafter, embodiments of the sealing device and rotor assembly are given in detail, one or more examples thereof shown in the drawings. Each example is provided for illustrative purposes of the Art and is not intended to limit the Art. Indeed, it will be apparent to those skilled in the art that modifications and changes are possible in the Art without departing from the scope or spirit of the claimed Art. For example, features illustrated or described as part of one embodiment can also be used in another embodiment to bring about further embodiments. Thus, this disclosure is intended to encompass such modifications and changes within the scope of the appended claims and their equivalents.

[0013] Detailed descriptions use numerals and letters to refer to features in the drawings. Similar or identical reference numerals in the drawings and descriptions are used to refer to similar or identical parts of the present invention. As used herein, the terms “first,” “second,” and “third” may be used interchangeably to distinguish one component from another and are not intended to indicate the location or importance of any individual component.

[0014] As used herein, the terms “upstream” (or “forward”) and “downstream” (or “backward”) refer to relative directions of fluid flow in a fluid path. For example, “upstream” refers to the direction in which the fluid is flowing, and “downstream” refers to the direction in which the fluid is flowing. The term “radially” refers to a relative direction substantially perpendicular to the axial centerline of a particular component, the term “axially” refers to a relative direction substantially parallel and / or coaxial with the axial centerline of a particular component, and the term “circumferentially” refers to a relative direction extending around the axial centerline of a particular component. Approximate terms such as “generally” or “about” include values ​​within plus or minus 10% of the stated value. When used in the context of angles or directions, such terms include a range of plus or minus 10 degrees of the stated angle or direction. For example, “generally perpendicular” includes any direction, e.g., within 10 degrees from perpendicular in a clockwise or counterclockwise direction.

[0015] As used herein, terms such as “clearance” should be understood to refer to any space or gap that may exist between two or more components of a system moving relative to one another during operation. As understood by those skilled in the art, clearance can correspond to annular gaps, linear gaps, rectangular gaps, or any other geometric shape, depending on the system, type of movement, and various other factors. In one application, clearance can refer to a radial gap or space between housing components surrounding one or more rotating blades in a compressor, turbine, etc. By controlling clearance using the techniques of this disclosure, the amount of leakage between the rotating blades and the housing can be actively reduced to improve operational efficiency while minimizing the possibility of friction (e.g., contact between housing components and rotating blades). As understood, leakage can correspond to any fluid, such as air, steam, or combustion gases.

[0016] As described herein, the radial gap between the turbine blades and the shroud may increase or decrease during operation due to temperature changes or other factors. For example, if the turbine heats up during operation, thermal expansion of the turbine housing components may cause the shroud to move radially away from the axis of rotation, thus increasing the clearance between the blades and the shroud. This is generally undesirable because combustion gases bypassing the blades through the radial gap are not captured by the blades and therefore not converted into rotational energy. This reduces the efficiency and power output of the turbine engine.

[0017] Referring here to the drawings, Figure 1 shows a schematic diagram of one embodiment of a turbomachinery, which in the illustrated embodiment is a gas turbine 10. Although industrial and onshore gas turbines are shown and described herein, this disclosure is not limited to onshore and / or industrial gas turbines unless specifically stated in the claims. For example, the present invention as described herein can be used in any type of turbomachinery, including, but is not limited to, steam turbines, aircraft gas turbines, or marine gas turbines.

[0018] As shown, the gas turbine 10 generally includes an inlet section 12, a compressor section 14 located downstream of the inlet section 12, a number of combustors (not shown) in a combustor section 16 located downstream of the compressor section 14, a turbine section 18 located downstream of the combustor section 16, and an exhaust section 20 located downstream of the turbine section 18. In addition, the gas turbine 10 may include one or more shafts 22 coupled between the compressor section 14 and the turbine section 18.

[0019] 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 24. Each rotor disk 24 may then be coupled to or form part of a shaft 22 extending through the compressor section 14. The compressor 14 further includes one or more stator vanes 27 arranged circumferentially around the shaft 22. The stator vanes 27 may be fixed to at least one of an outer casing 47 and an inner casing 46 extending circumferentially around the rotor blades 26.

[0020] The 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 connected to each rotor disk 28. Each rotor disk 28 may then be coupled to or form part of a shaft 22 extending through the turbine section 18. The turbine section 18 may further include an outer turbine casing 31 and an inner turbine casing 33 that circumferentially enclose a portion of the shaft 22 and the rotor blades 30, thereby at least partially defining a hot gas path 32 through the turbine section 18. The inner turbine casing 33 may be configured to support a plurality of stationary nozzles 29 extending radially inward from the inner circumference of the inner turbine casing 33. The inner turbine casing 33 may also be configured to support a plurality of shroud sections or blocks 35 that, when positioned around the inner circumference of the inner turbine casing 33, abut each other to define a substantially cylindrical shape surrounding the shaft 22.

[0021] During operation, a working fluid such as air flows through the inlet section 12 into the compressor section 14, where the air is gradually compressed, thereby supplying pressurized air to the combustors in the combustor section 16. The pressurized air is mixed with fuel and burned in each combustor to produce combustion gases 34. The combustion gases 34 flow from the combustor section 16 to the turbine section 18 through the high-temperature gas path 32, where energy (kinetic and / or thermal energy) is transferred from the combustion gases 34 to the rotor blades 30, causing the shaft 22 to rotate. This mechanical rotational energy can then be used to supply power to the compressor section 14 and / or generate electricity. The combustion gases 34 that have left the turbine section 18 can then be exhausted from the gas turbine 10 through the exhaust section 20.

[0022] As shown, the gas turbine 10 may define an axial direction A substantially parallel to and / or along the axial centerline 23 of the gas turbine 10, a radial direction R perpendicular to the axial centerline 23, and a circumferential direction C extending around the axial centerline 23.

[0023] Figure 2 is a cross-sectional view of the main components of an exemplary gas turbine compressor section, including a rotor assembly and a stator assembly. The compressor section 14 includes a rotor assembly positioned within an inner casing 46 so as to define a flow path for compressed air 38. The rotor assembly also defines an inner flow path boundary 62 of the flow path 38, and the stator assembly defines an outer flow path boundary 64 of the flow path for the compressed air 38. The compressor section 14 includes a plurality of stages, each stage including a row of circumferentially spaced rotor blades 26 and a row of stator vanes 27. In this embodiment, the rotor blades 26 are coupled to the rotor disk 24, and each rotor blade extends radially outward from the rotor disk 24. Each rotor blade 26 includes an airfoil portion extending radially from an inner blade platform 58 to a rotor blade tip 60. A clearance 72 may be defined radially between the tip 60 of the airfoil portion of the rotor blade 26 and the inner casing 46. Similarly, the stator assembly includes a plurality of rows of stator vanes 27, each row of vanes 27 being positioned between adjacent rows of rotor blades 26. The compressor stages are configured to cooperate with a working fluid of compressed air 38, such as ambient air, and the working fluid is compressed in subsequent stages. Each row of stator vanes 27 extends radially inward from the inner casing 46 and includes an airfoil portion extending from an outer vane platform 66 to a vane tip 68. A clearance 70 may be defined radially between both the tip 68 of the airfoil portion of the stator vane 27 and the rotor disk 24. Each airfoil portion includes a leading edge and a trailing edge as shown.

[0024] FIG. 3 shows an exemplary turbine section 18 of a gas turbine 10 that includes a plurality of turbine stages arranged in a serial flow order. Each stage of the turbine includes a row of stationary turbine nozzles or vanes (e.g., stationary nozzle 29) disposed axially adjacent to a corresponding rotating row of turbine rotor blades (e.g., blade 30). Four turbine stages are shown in FIG. 3. The exact number of stages of the turbine section 18 may be more or less than the four stages shown in FIG. 3. The four stages are merely an example of one turbine design and are in no way intended to limit the presently claimed turbine rotor blades.

[0025] Each stage includes a plurality of stationary nozzles 29 and a plurality of turbine rotor blades 30. The stationary nozzles 29 are mounted on the inner turbine casing 33 and are arranged annularly around the axis of the turbine rotor 36. Each stationary nozzle 29 may extend radially inward from the inner casing 33 to a stator shroud 102 coupled to the tip of the stationary nozzle 29. When the stationary nozzles 29 are installed around the inner periphery of the inner turbine casing 33, the stator shrouds 102 abut one another so as to define a substantially cylindrical shape surrounding the shaft turbine rotor 36. A clearance 104 may be defined radially between the stator shroud 102 and the turbine rotor 36. The clearance 104 may extend continuously in the circumferential direction C around the turbine rotor 36.

[0026] As shown, the turbine rotor blades 30 are arranged in annularly around the turbine rotor 36 and coupled to the turbine rotor 36. Each turbine rotor blade 30 may include an airfoil having a leading edge, a trailing edge, positive pressure sides, and negative pressure sides. In some embodiments, as shown, the turbine rotor blades 30 may include a tip shroud 106. When the turbine rotor blades 30 are installed around the inner circumference of the inner turbine casing 33, the tip shroud 106 can abut against each other to define a substantially cylindrical shape surrounding the airfoil and the turbine rotor blades 30 and the turbine rotor 36. In many embodiments, a clearance 108 may be defined radially between the stator shroud 102 and the turbine rotor 36. The clearance 108 may extend continuously in the circumferential direction C around the turbine rotor 36.

[0027] Figure 4 shows a cross-sectional view of the rotor assembly 19 of the turbine section 18 along the axial centerline of the gas turbine 10 according to an embodiment of the present disclosure. As shown in Figure 4, the plurality of rotor blades 30 extend radially outward from the rotor disk 28. During operation of the gas turbine 10, the rotor blades 30 can move in the circumferential direction C (around the centerline of the gas turbine 10). In many embodiments, each rotor blade 30 in the plurality of rotor blades 30 includes a platform 110, a tip rail 106, and an airfoil 112 extending radially between the platform 110 and the tip rail 106. As shown, the tip rails 106 of each rotor blade 30 in the plurality of rotor blades 30 abut each other and collectively form a tip rail ring 114 that extends continuously circumferentially around the centerline of the gas turbine 10. For example, the tip rail ring 114 extends around the turbine rotor 36. In many embodiments, the inner turbine casing 33 may be spaced apart (e.g., radially) from the tip rail ring 114 so that a clearance 108 is defined between the tip rail ring 114 and the inner turbine casing 33. In some embodiments, the inner turbine casing 33 can support a plurality of shroud sections or blocks 35 that, when installed around the inner circumference of the inner turbine casing 33, abut each other to define a substantially cylindrical shape surrounding a portion of the turbine rotor 36 of the gas turbine 10. For example, a shroud block 35 may be supported by the inner turbine casing 33 so as to surround or enclose one of a plurality of stages of the turbine section 18 of the rotor blades 30. In many embodiments, the shroud blocks 35 can collectively define a shroud ring 115 that abuts each other in the circumferential direction C and is radially spaced apart from the tip rail ring 114. In such embodiments, the clearance 108 can be defined between the tip rail 106 of the rotor blade 30 and the shroud block 35 of the inner turbine casing 33.

[0028] Figure 5 shows a perspective view of two adjacent rotor blades 30 according to an embodiment of the present disclosure. As shown, each rotor blade includes a platform 110, a tip rail 106, and an airfoil shaped section 112 extending between the platform 110 and the tip rail 106.

[0029] The airfoil section 112 can generally have an aerodynamic profile and may include a positive pressure sidewall, an opposing negative pressure sidewall, a leading edge 120, and a trailing edge 122. The positive pressure sidewall generally comprises the aerodynamically concave outer surface of the airfoil section 112. Similarly, the negative pressure sidewall can generally define the aerodynamically convex outer surface of the airfoil section 112. In many embodiments, the airfoil section 112 may extend from a root 124 coupled to a platform 110 to a tip 126, and the tip rail 106 may extend from the tip 126 across the airfoil section 112. In various embodiments, each rotor blade 30 may include a shank 128 extending radially inward from the platform 110. As is generally understood, the shank 128 may include a dovetail 129 that connects the rotor blade 30 to the rotor disc.

[0030] Figure 6 shows a sealing device 200 for use in turbomachinery such as the gas turbine 10 described herein, according to an embodiment of the present disclosure. The sealing device 200 may include stationary components 202 of the gas turbine 10, such as the inner casing 46 of the compressor section 14, one or more stator vanes 27 of the compressor section 14, the inner turbine casing 33, one or more stationary nozzles 29 of the turbine section 18, one or more shroud blocks 35, or other stationary components of the gas turbine 10.

[0031] The sealing device 200 may further include a rotating component 204, i.e., a component that rotates in the circumferential direction C of the gas turbine 10. In many embodiments, the rotating component 204 is mounted directly or indirectly to the shaft 22, thereby allowing it to rotate in the circumferential direction C together with other components of the gas turbine 10. The rotating component 204 may be, but is not limited to, a rotor blade 26 of the compressor section 14, a rotor disk 24 of the compressor section 14, a rotor blade 30 of the turbine section 18, or a rotor disk 28 of the turbine section 18. In an exemplary embodiment, the rotating component 204 may be the tip rail 106 of the rotor blade 30.

[0032] As shown in Figure 6, a clearance 206 may be defined between the stationary component 202 and the rotating component 204 to prevent frictional wear between them. As can be understood, due to the high operating temperature of the gas turbine 10, either or both of the stationary component 202 and the rotating component 204 may experience thermal expansion and contraction, thereby changing the distance between components 202, 204 and the clearance 206. The clearance 206 between the stationary component 202 and the rotating component 204 may represent any of the other clearances described herein, e.g., clearance 70, clearance 72, clearance 104, and / or clearance 108. In exemplary embodiments, the clearance 206 may be defined between the tip shroud 106 of the turbine rotor blade 30 and a plurality of shroud blocks 35 (Figure 4). Those skilled in the art should understand that this subject matter is not limited to any particular configuration, and that the sealing device 200 described herein may be advantageous for any stationary and rotating components of the gas turbine 10.

[0033] As shown in Figure 6, the stationary components may include an outer wall 208, a first inner wall 210, and a second inner wall 212. The first inner wall 210 and the second inner wall 212 may be spaced apart from the outer wall 208 (e.g., radially spaced) such that a first slot 216 is defined between the outer wall 208 and the first inner wall 210, and a second slot 218 is defined between the outer wall 208 and the second inner wall 212. In many embodiments, the first inner wall 210 and the second inner wall may be aligned with each other in the radial direction R, and both may generally extend in the axial direction A. Similarly, the first slot 216 and the second slot 218 may be aligned radially and axially, thereby collectively forming a rectangular slot. In various embodiments, the first inner wall 210 and the second inner wall 212 may be spaced apart from each other in the axial direction A such that the opening 220 is defined axially between the inner walls 210 and 212.

[0034] In many embodiments, the outer wall 208 may be generally parallel to both the first inner wall 210 and the second inner wall 212. In various embodiments, the stationary components 202 may include side walls 214 spaced apart from each other axially and extending between the outer wall 208 and either the first inner wall 210 or the second inner wall 212. For example, the side walls may extend generally perpendicular to the outer wall 208 and the inner walls 210, 212, thereby defining a rectangular slot that is generally continuous in the circumferential direction C.

[0035] In exemplary embodiments, the rotating component 204 may be spaced apart from the stationary component 202, for example, the rotating component 204 may be positioned radially inward of the stationary component 202. For example, the rotating component 204 can move circumferentially C relative to the stationary component 202. In some embodiments, the rotating component 204 may include a tip rail 222 extending radially outward from the rotating component 204. In many embodiments, the tip rail 222 may be the tip rail 106 of the turbine rotor blade 30 described above.

[0036] In many embodiments, as shown in Figure 6, a floating seal 224 can be positioned between the stationary component 202 and the rotating component 204 to limit leak flow 219 between the stationary component 202 and the rotating component 204, thereby increasing the efficiency of the gas turbine 10. The leak flow 219 may be excess air (if the sealing device 200 is located in the compressor section 14) or excess combustion gas (if the sealing device 200 is located in the turbine section 18). As can be understood, minimizing the amount of leak flow 219 passing through the clearance 206 can favorably increase the overall efficiency of the gas turbine 10 by minimizing waste. In addition, the floating seal 224 does not have to come into contact with any surface during the operation of the gas turbine 10, and as a result, frictional wear on the seal is reduced and / or completely eliminated.

[0037] In exemplary embodiments, the floating seal 224 may include an axial member 226 having a first arm 228 extending into a first slot 216, a second arm 230 extending into a second slot 218, and an intermediate portion 229 extending between the arms 228, 230. In many embodiments, the floating seal 224 may include a first radial member 232 and a second radial member 234 extending from the axial member 226. In various embodiments, the axial member 226 may be generally perpendicular to the radial members 232, 234. The radial members 232, 234 may be axially spaced apart from each other so as to extend on both sides of the tip rail 222. In some embodiments, the floating seal 224 may be a single continuous seal extending seamlessly between the axial member 226 and the radial members 232, 234. For example, radial members 232 and 234 can extend from the axial member 226 at the division between the arms 228 and 230 and the intermediate portion 229 of the axial member 226.

[0038] In certain embodiments, multiple magnets 235 can be coupled to a stationary component 202, a rotating component 204, and a floating seal 224. The multiple magnets 235 can include all magnets in the sealing device 200, for example, magnets 237, 238, 241, 242, 244, 246, 249, 250, and 252. For example, the multiple magnets 235 may be arranged so that the floating seal 224 is housed between the stationary component 202 and the rotating component 204. For example, the multiple magnets 235 may be arranged to generate a repulsive magnetic force that favorably maintains the alignment of the floating seal 224. In addition, the multiple magnets 235 may be arranged so that the generated repulsive magnetic force prevents the floating seal 224 from contacting both the stationary component 202 and the rotating component 204. In this way, the floating seal 224 can "float" or "hover" within the clearance 206 relative to the stationary component 202 and the rotating component 204, which advantageously extends the life of the floating seal 224 due to reduced frictional wear over time. During operation of the gas turbine 10, the floating seal 224 may be separated from both the stationary component 202 and the rotating component 204 (without contact with either 202 or 204) by the repulsive magnetic force generated by the multiple magnets 235, resulting in the floating seal 224 "hovering" or "floating" within the clearance 206, thereby limiting the leakage flow 219 across the clearance 206 without causing frictional wear on the components 202 and 204.

[0039] The multiple magnets 235 include a first pair of magnets 236 and a second pair of magnets 240 embedded within the stationary component 202. For example, the first pair of magnets 236 may be positioned within the stationary component across the first slot 216. In many embodiments, the first pair of magnets 236 may be embedded within the stationary component 202 so as to partially define the first slot 216. Similarly, the second pair of magnets 240 may be positioned within the stationary component across the second slot 218. In many embodiments, the second pair of magnets 240 may be embedded within the stationary component 202 so as to partially define the second slot 218.

[0040] As shown in Figure 6, the first pair of magnets 236 may include a first outer magnet 237 and a first inner magnet 238. The first outer magnet 237 may be positioned within the outer wall 208 of the stationary component 202 and coupled to the outer wall 208 such that the first outer magnet 237 at least partially defines the boundary of the first slot 216. In many embodiments, the first inner magnet 238 may be positioned within the first inner wall 210 and coupled to the first inner wall 210 such that the first inner magnet 238 faces the first outer magnet 237 and at least partially defines the first slot 216. In exemplary embodiments, the first outer magnet 237 and the first inner magnet 238 may be radially aligned with respect to each other so as to extend coaxially with respect to the radial centerlines of the magnets 237, 238, which is advantageous as it allows for a uniform magnetic field within the first slot 216 that enhances the alignment of the floating seal 224. In various embodiments as shown, the first pair of magnets 236 can generally be molded as a "T" having a longer portion facing the first slot 216.

[0041] Similarly, the second pair of magnets 240 may include a second outer magnet 241 and a second inner magnet 242. The second outer magnet 241 may be positioned within the outer wall 208 of the stationary component 202 and coupled to the outer wall 208 such that the second outer magnet 241 at least partially defines the boundary of the second slot 218. In many embodiments, the second inner magnet 242 may be positioned within the second inner wall 212 and coupled to the second inner wall 212 such that the second inner magnet 242 faces the second outer magnet 241 and at least partially defines the second slot 218. In exemplary embodiments, the second outer magnet 241 and the second inner magnet 242 may be radially aligned with respect to each other so as to extend coaxially with respect to the radial centerlines of the magnets 241, 242, which is advantageous as it allows for a uniform magnetic field within the second slot 218 that enhances the alignment of the floating seal 224. In various embodiments as shown, the second pair of magnets 240 can generally be molded as a "T" having a longer portion facing the second slot 218.

[0042] As shown in Figure 6, the first axial seal magnet 244 may be attached to the first arm 228 of the axial member 226 of the floating seal 224. For example, the first axial seal magnet 244 may be connected to the first arm 228 via a connecting member 245 which can be fixedly coupled to the first arm 228 by welding or other means. In other embodiments, the first axial seal magnet 244 may be connected to the first arm 228 in various other ways. The first axial seal magnet may extend from the first arm 228 into the first slot 216 and be positioned between and spaced apart from the first pair of magnets 236. In an exemplary embodiment, the first axial seal magnet 244 may be repelled (by repulsive magnetic force) from the first pair of magnets 236, thereby holding the first axial seal magnet 244 in a predetermined position radially between the first pair of magnets 236 and moving away from it, due to the repulsive magnetic force exerted on the first axial seal magnet 244 by the first pair of magnets 236.

[0043] Similarly, a second axial seal magnet 246 may be attached to a second arm 230 of the axial member 226 of the floating seal 224. For example, the second axial seal magnet 246 may be connected to the first arm 228 via a connecting member 247 which can be fixedly coupled to the second arm 230 by welding or other means. In other embodiments, the second axial seal magnet 246 may be connected to the second arm 230 in various other ways. The second axial seal magnet 246 may extend from the second arm 230 into a second slot 218 and be positioned between and spaced apart from the second pair of magnets 240. In an exemplary embodiment, the second axial seal magnet 246 may be repelled (by repulsive magnetic force) from the second pair of magnets 240, thereby holding the second axial seal magnet 246 in a predetermined position radially between the second pair of magnets 240 and moving away from it, due to the repulsive magnetic force exerted on the second axial seal magnet 246 by the second pair of magnets 240.

[0044] As shown in Figure 6, the first pair of magnets 236 and the first axial sealing magnet 244 may be axially spaced apart from the second pair of magnets 240 and the second axial sealing magnet 246 in order to evenly distribute the magnetic force and maintain the radial alignment of the floating seal 224 at all locations. In this way, the floating seal 224 can be pushed into a radial position between the pair of magnets 236 and 240 and spaced apart therefrom by the repulsive magnetic force that the pair of magnets 236 and 240 exert on the axial sealing magnets 244 and 246.

[0045] In exemplary embodiments, the plurality of magnets 235 further include a third pair of magnets 248 positioned opposite each other and embedded within the floating seal 224. For example, the third pair of magnets 248 may be embedded within a first radial member 232 and a second radial member 234 that are opposite each other. In many embodiments, the third pair of magnets 248 may include a first radial seal magnet 249 embedded within the first radial member 232 and a second radial seal magnet 250 embedded within the second radial member 234. In exemplary embodiments, the first radial seal magnet 249 and the second radial seal magnet 250 may be axially aligned with respect to the axial centerlines of the magnets 249, 250, which is advantageous as it allows for a uniform magnetic field in axial A that enhances the alignment of the floating seal 224. In various embodiments as shown, the third pair of magnets 248 can generally be shaped as a "T" with a longer portion facing the tip rail magnet 252.

[0046] In many embodiments, the tip rail magnet 252 is attached to the tip rail 222 of the rotating component 204 such that the tip rail magnet 252 rotates together with the rotating component 204 between the radial members 232, 234 of the floating seal 224 in the circumferential direction C. As shown in Figure 6, the tip rail magnet 252 may extend between the third pair of magnets 248 such that the third pair of magnets 248 are repelled by the magnetic field generated by the tip rail magnet 252, thereby advantageously aligning the floating seal 224 in the axial direction A. For example, the tip rail magnet 252 can be connected to the tip rail 222 via a connecting member 253 which can be fixedly coupled to the tip rail 222 by welding or other means. In other embodiments, the second axial seal magnet 246 may be connected to the second arm 230 in various other ways. The tip rail magnet 252 may extend from the tip rail 222 into a space defined between the magnets 249, 250. In an exemplary embodiment, the third pair of magnets 248 may be repelled (by repulsive magnetic force) from the tip rail magnet 252, thereby the magnetic field generated by the third pair of magnets 248 and the tip rail magnet 252 holds the floating seal 224 in a predetermined position in the axial direction.

[0047] In many embodiments, each magnet in the plurality of magnets 235 described herein may be a permanent magnet, and therefore the magnets 235 are made of a material that is magnetized by an external magnetic field and remains magnetized after the external magnetic field is removed. In this way, the magnets 235 continuously generate their own magnetic fields. In many embodiments, the magnets 235 may be in the form of a piece of metallic material having its constituent atoms arranged such that the material exhibits magnetic properties such as attracting other iron-containing objects or aligning itself in an external magnetic field. In exemplary embodiments, the magnets 235 may be Alnico magnets, which are permanent magnets mainly composed of a combination of aluminum (Al), nickel (Ni), and cobalt (Co), but may also include copper, iron, and titanium. Alnico magnets may be capable of operating at extremely high temperatures, such as above 1000°F.

[0048] Although multiple magnets 235 are shown in Figure 6 having poles labeled (N pole "N" and S pole "S") at specific ends, it is assumed that each pole can be switched, thereby having the same configuration but with opposite magnetic pole orientations, which is within the scope of this disclosure.

[0049] In various embodiments, the sealing assembly 200 described herein may be used in any of the clearances described herein, e.g., clearance 70, clearance 72, clearance 104, and / or clearance 108, to limit leakage flow between the stationary and rotating components of a gas turbine. In exemplary embodiments, the sealing assembly 200 described herein may be used in the rotor assembly 19 (Figure 4) described herein, such as within clearance 108. In such embodiments, the shroud block 35 may be a stationary component. The tip rail ring 114 may be a rotating component. The floating seal 224 may extend across clearance 108 to advantageously limit and / or prevent combustion gases from passing through clearance 108. In addition, the floating seal 224 described herein may be advantageously wear-resistant and self-aligning due to a plurality of magnets 235. For example, the magnets 235 ensure that the floating seal 224 does not come into contact with components 202, 204, thereby minimizing frictional wear of the floating seal 224. In addition, the magnet 235 maintains the proper alignment of the floating seal 224 under all operating conditions of the gas turbine 10 (as described above, the clearance changes based on the thermal conditions of the gas turbine 10).

[0050] In addition, in exemplary embodiments, the floating seal 224 may extend circumferentially around the centerline 23 of the gas turbine 10, thereby advantageously preventing leakage across the clearance 206 at all circumferential locations. For example, Figure 7 shows a cross-sectional view of a rotor assembly of a turbine section having a floating seal 224 used in the clearance 108 between the tip rail ring 114 and the shroud ring 115. As shown, the floating seal 224 can extend circumferentially around the centerline of the gas turbine 10 (continuously or in one of several connected segments) so that the clearance 108 is covered 360 degrees around the centerline of the gas turbine 10. As shown, the dashed line represents the portion of the floating seal 224 that is housed within the stationary component 202 (or the shroud ring 115 in the embodiment of Figure 7).

[0051] This specification discloses the present invention, including its best mode, and uses examples to enable any person skilled in the art to practice the invention, including the fabrication and use of any apparatus or system and the execution of any incorporated method. The patentable scope of the present invention is defined by the claims and may include other embodiments that a person skilled in the art may conceive. Such other embodiments are intended to be within the claims if they include structural elements that are not different from the language of the claims, or equivalent structural elements that do not substantially differ from the language of the claims. [Explanation of Symbols]

[0052] 10. Gas turbines, stationary gas turbines 12 Entrance Section 14 Compressor Section 16. Combustor Section 18 Turbine Section 19 Rotor Assembly 20 Exhaust Section 22 shafts 23 Axial center line 24 Rotor Discs 26 rotor blades 27. State vanes 28 Rotor Discs 29 Stationary nozzle 30 Turbine rotor blades 31. Outer turbine casing 32 High-temperature gas pathway 33. Inner turbine casing 34 Combustion gases 35 Shroud sections, shroud blocks 36 Shaft Turbine Rotor 38 Compressed air, flow path 46 Inner casing 47 Outer casing 58 Inner blade platform 60 rotor blade tip 62 Inner channel boundary 64 Outer channel boundary 66 Outer vane platform 68 vane tip 70 Clearance 72 Clearance 102 Stator Shroud 104 Clearance 106 End shroud, end rail 108 Clearance 110 platforms 112 Airfoil 114 Tip Rail Ring 115 Shroud Ring 120 leading edge 122 Trailing edge 124 Root 126 Tip 128 Shank 129 Dovetail 200 sealing devices, sealing assemblies 202 Stationary Components 204 Rotational Components 206 Clearance 208 Exterior Wall 210 First inner wall 212 Second Inner Wall 214 Side wall 216 First slot 218 Second slot 219 Leakage 220 opening 222 Front Rail 224 Floating Seal 226 Axial member 228 First Arm 229 Middle part 230 Second Arm 232 First radial member 234 Second radial member 235 Magnets 236 The first pair of magnets 237 First outer magnet 238 First inner magnet 240 Second pair of magnets 241 Second outer magnet 242 Second inner magnet 244 First axial seal magnet 245 Connecting Member 246 Second axial sealing magnet 247 Connecting Member 248 The third pair of magnets 249 First radially sealing magnet 250 Second radial sealing magnet 252 Tip Rail Magnet 253 Connecting Member A-axis C Circumferential direction R Radial direction

Claims

1. A sealing device (200) for use in a gas turbine (10), wherein the sealing device (200) A stationary component (202) having an outer wall (208), a first inner wall (210), and a second inner wall (212), wherein the first inner wall (210) and the second inner wall (212) are spaced apart from the outer wall (208) such that a first slot (216) is defined between the outer wall (208) and the first inner wall (210), and a second slot (218) is defined between the outer wall (208) and the second inner wall (212), A rotating component (204) spaced apart from the stationary component (202), wherein the rotating component (204) moves relative to the stationary component (202), and the rotating component (204) includes a tip rail (222), A floating seal (224) disposed between the stationary component (202) and the rotating component (204), wherein the floating seal (224) includes an axial member (226) having a first arm (228) extending into the first slot (216) and a second arm (230) extending into the second slot (218), and the floating seal (224) includes a first radial member (232) and a second radial member (234) extending from the axial member (226) through an opening (220) defined between the first inner wall (210) and the second inner wall (212), A plurality of magnets (235) coupled to the stationary component (202), the rotating component (204), and the floating seal (224), wherein the plurality of magnets (235) are arranged such that the floating seal (224) is housed between the stationary component (202) and the rotating component (204), and A sealing device (200) comprising the above.

2. The sealing device (200) according to claim 1, wherein the plurality of magnets (235) includes a first pair of magnets (236) and a second pair of magnets (240) embedded in the stationary component (202), the first pair of magnets (236) are positioned facing each other across the first slot (216), and the second pair of magnets (240) are positioned facing each other across the second slot (218).

3. The sealing device (200) according to claim 2, wherein the first pair of magnets (236) includes a first outer magnet (237) disposed within the outer wall (208) and a first inner magnet (238) disposed within the first inner wall (210), and the second pair of magnets (240) includes a second outer magnet (241) disposed within the outer wall (208) and a second inner magnet (242) disposed within the second inner wall (212).

4. The sealing device (200) according to claim 2, wherein a first axial sealing magnet (244) is attached to the first arm (228) of the axial member (226), a second axial sealing magnet (246) is attached to the second arm (230) of the axial member (226), the first axial sealing magnet (244) extends between the first pair of magnets (236), and the second axial sealing magnet (246) extends between the second pair of magnets (240).

5. The sealing device (200) according to claim 4, wherein the first axial sealing magnet (244) is repelled by the first pair of magnets (236), and the second axial sealing magnet (246) is repelled by the second pair of magnets (240), thereby aligning the floating seal (224) in the radial direction (R).

6. The sealing device (200) according to claim 1, further comprising a third pair of magnets (248) arranged opposite to each other and embedded within the floating seal (224), wherein the plurality of magnets (235) are further provided.

7. The sealing device (200) according to claim 6, wherein the third pair of magnets (248) includes a first radial sealing magnet (249) embedded in the first radial member (232) and a second radial sealing magnet (250) embedded in the second radial member (234).

8. The sealing device (200) according to claim 7, wherein a tip rail magnet (252) is attached to the tip rail (222) of the rotating component (204), the tip rail magnet (252) extends between the third pair of magnets (248), the tip rail magnet (252) is repelled by the third pair of magnets (248), and thereby the floating seal (224) is aligned in the axial direction (A).

9. The sealing apparatus (200) according to claim 1, wherein the plurality of magnets (235) are permanent magnets (235).

10. The sealing apparatus (200) according to claim 1, wherein the plurality of magnets (235) are Alnico magnets (235).

11. A rotor assembly (19) for a gas turbine (10), wherein the rotor assembly (19) is A plurality of rotor blades (26) extending radially outward from a rotor disk (24), wherein the plurality of rotor blades (26) move circumferentially (C) during the operation of the gas turbine (10), and each rotor blade (26) in the plurality of rotor blades (26) includes a platform (110), a tip rail (222), and an airfoil portion (112) extending between the platform (110) and the tip rail (222), and the tip rail (222) of each rotor blade (26) in the plurality of rotor blades (26) collectively form a tip rail ring (114) extending circumferentially around the centerline (23) of the gas turbine (10), A plurality of shroud blocks (35) that collectively form a shroud ring (115) extending circumferentially around the center line (23) of the gas turbine (10) and radially spaced apart from the tip rail ring (114), wherein each shroud block (35) has an outer wall (208), a first inner wall (210), and a second inner wall (212), and the first inner wall (210) and the second inner wall (212) are radially spaced apart from the outer wall (208) such that a first slot (216) is defined between the outer wall (208) and the first inner wall (210), and a second slot (218) is defined between the outer wall (208) and the second inner wall (212), and A floating seal (224) disposed between the tip rail ring (114) and the casing (33), wherein the floating seal (224) includes an axial member (226) having a first arm (228) extending into the first slot (216) and a second arm (230) extending into the second slot (218), and the floating seal (224) includes a first radial member (232) and a second radial member (234) extending from the axial member (226), A plurality of magnets (235) coupled to the shroud ring (115), the tip rail ring (114), and the floating seal (224), wherein the plurality of magnets (235) are arranged such that the floating seal (224) is housed between the shroud ring (115) and the tip rail ring (114), and A rotor assembly (19) comprising:

12. The rotor assembly (19) according to claim 11, wherein the plurality of magnets (235) includes a first pair of magnets (236) and a second pair of magnets (240) embedded in the shroud ring (115), the first pair of magnets (236) being positioned opposite each other across the first slot (216), and the second pair of magnets (240) being positioned opposite each other across the second slot (218).

13. The rotor assembly (19) according to claim 12, wherein the first pair of magnets (236) includes a first outer magnet (237) disposed within the outer wall (208) and a first inner magnet (238) disposed within the first inner wall (210), and the second pair of magnets (240) includes a second outer magnet (241) disposed within the outer wall (208) and a second inner magnet (242) disposed within the second inner wall (212).

14. The rotor assembly (19) according to claim 12, wherein a first axial sealing magnet (244) is attached to the first arm (228) of the axial member (226), a second axial sealing magnet (246) is attached to the second arm (230) of the axial member (226), the first axial sealing magnet (244) extends between the first pair of magnets (236), and the second axial sealing magnet (246) extends between the second pair of magnets (240).

15. The rotor assembly (19) according to claim 14, wherein the first axial seal magnet (244) is repelled by the first pair of magnets (236), and the second axial seal magnet (246) is repelled by the second pair of magnets (240), thereby aligning the floating seal (224) in the radial direction (R).

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