Turbomachinery clearance control using brush seals with magnetically responsive filaments

Abstract

To provide sealing arrangements for use in a gas turbine, and rotor assemblies for a turbomachine.SOLUTION: A sealing arrangement (200) includes a clearance (206) defined between a stationary component (202) and a rotating component (204) separated therefrom, and further includes multiple magnets (212) embedded in the rotating component (204). The sealing arrangement (200) further includes a brush seal (208) having a frame (215) and multiple magnetically responsive filaments (210). The multiple magnetically responsive filaments (210) each extend from the frame (215) to a free end. The multiple magnetically responsive filaments (210) are attracted to the rotating component (204) by the multiple magnets (212). The magnetically responsive filaments (210) at least partially cover the clearance (206), such that a flow of fluid across the clearance (206) is restricted.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present disclosure generally relates to clearance in turbomachinery. In particular, the present disclosure relates to controlling clearance between stationary and rotating components in turbomachinery. [Background Art]

[0002] Turbomachinery is utilized in various industries and applications for energy transfer purposes. For example, a gas turbine engine generally includes a compressor section, a combustion section, a turbine section, and an exhaust section. The compressor section gradually increases the pressure of a working fluid entering the gas turbine engine and supplies the compressed working fluid to the combustion section. The compressed working fluid and a fuel (e.g., natural gas) are mixed within the combustion section and burned in a combustion chamber to produce high-pressure, 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 may rotate a rotor shaft connected, for example, to a generator to generate electricity. The combustion gases then exit the gas turbine via the exhaust section.

[0003] In particular applications, there may be clearance between components that move relative to one another within turbomachinery. For example, clearance may exist between rotating components and stationary components in rotating machinery such as compressors and turbines. The clearance may increase or decrease during operation of the rotating machine due to temperature changes or other factors. As can be appreciated, smaller clearances result in less fluid leakage between the blades and the surrounding shroud, which can improve the performance and efficiency of the compressor or turbine. However, smaller clearances also increase the likelihood of a rub condition. Operating conditions also affect the likelihood of a rub condition. For example, the likelihood of a rub condition 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 and a rotating component spaced apart from the stationary component. A clearance is defined between the stationary component and the rotating component. The sealing device further includes a plurality of magnets embedded within the rotating component. The sealing device further includes a frame and a brush seal having a plurality of magnetically responsive filaments. Each of the plurality of magnetically responsive filaments extends from the frame to a free end. The plurality of magnetically responsive filaments are attracted to the rotating component by the plurality of magnets. The plurality of magnetically responsive filaments at least partially cover the clearance such that fluid flow across the clearance is restricted.

[0008] According to another embodiment, a rotor assembly for a turbomachinery 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 shroud, and an airfoil extending between the platform and the tip shroud. The tip shrouds of each rotor blade in the plurality of rotor blades collectively form a shroud ring extending circumferentially around the centerline of the turbomachinery. A casing is spaced apart from the shroud ring, and the casing has a plurality of shroud blocks positioned internally such that a clearance is defined between the shroud ring and the shroud blocks. A plurality of magnets are embedded within the shroud ring. The rotor assembly further includes a frame and a brush seal having a plurality of magnetically responsive filaments. Each of the plurality of magnetically responsive filaments extends from the frame to a free end. The plurality of magnetically responsive filaments are attracted to a rotating component by the plurality of magnets. The plurality of magnetically responsive filaments cover the clearance at least partially so as to restrict the flow of fluid across the clearance.

[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 figure shows a sealing device according to an embodiment of the present disclosure. [Figure 6] This is a cross-sectional view of a sealing device according to an embodiment of the present disclosure. [Figure 7] This is a cross-sectional view of a sealing device according to an embodiment of the present disclosure. [Figure 8] This figure shows a sealing device having a brush seal in an engagement position according to an embodiment of the present disclosure. [Figure 9] This figure shows a sealing device having a brush seal in the disengaged position according to an embodiment of the present disclosure. [Figure 10] This is a perspective view of a brush seal 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 of which are 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 illustrated, and a plurality of rotor blades 30 extending radially outwardly from and connected to each rotor disk 28. Each rotor disk 28 may then be coupled to or form a portion of a shaft 22 extending through the turbine section 18. The turbine section 18 further includes an outer turbine casing 31 and an inner turbine casing 33 that circumferentially surround 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 stages 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 installed around the inner circumference of the inner turbine casing 33, abut against each other to define a substantially cylindrical shape surrounding the shaft 22.

[0021] In operation, a working fluid such as air flows into a compressor section 14 through an inlet section 12, where the air is progressively compressed, thereby providing pressurized air to combustors in a combustor section 16. The pressurized air is mixed with fuel and combusted within each combustor to generate combustion gases 34. The combustion gases 34 flow from the combustor section 16 into the turbine section 18 through the hot gas path 32, where energy (kinetic energy and / or thermal energy) is transferred from the combustion gases 34 to the rotor blades 30, thereby causing the shaft 22 to rotate. The mechanical rotational energy may then be used to power the compressor section 14 and / or for power generation. The combustion gases 34 exiting the turbine section 18 may then be exhausted from the gas turbine 10 via an exhaust section 20.

[0022] As shown, the gas turbine 10 can 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 to define a flow path for compressed air 38. The rotor assembly also defines an inner flow boundary 62 of the flow path 38, and the stator assembly defines an outer flow boundary 64 of the flow path for 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 a rotor disk 54, and each rotor blade extends radially outward from the rotor disk 54. Each rotor blade 26 includes an airfoil extending radially from an inner blade platform 58 to a rotor blade tip 60. A clearance 72 may be defined radially between the airfoil tip 60 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 successive stages. Each row of stator vanes 27 includes an airfoil extending radially inward from the inner casing 46 and extending from an outer vane platform 66 to a vane tip 68. A clearance 70 may be defined radially between the airfoil tip 68 of the stator vane 27 and the rotor disk 54. Each airfoil includes a leading edge and a trailing edge as shown.

[0024] Figure 3 shows an exemplary turbine section 18 of a gas turbine 10, which includes multiple turbine stages arranged in a series flow sequence. Each stage of the turbine includes a row of stationary turbine nozzles or vanes (e.g., stationary nozzles 29) arranged axially adjacent to the corresponding rotating row of turbine rotor blades (e.g., blades 30). Four turbine stages are shown in Figure 3. The exact number of stages in the turbine section 18 may be more or less than the four stages shown in Figure 3. The four stages are merely illustrative of one turbine design and are not intended to limit the currently asserted turbine rotor blades in any way.

[0025] Each stage comprises a plurality of stationary nozzles 29 and a plurality of turbine rotor blades 30. The stationary nozzles 29 are mounted in an inner turbine casing 33 and arranged in an annular manner 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 positioned around the inner circumference of the inner turbine casing 33, the stator shrouds 102 abut each other to define a substantially cylindrical shape surrounding the shaft turbine rotor 36. A clearance 104 may be defined radially between the stator shrouds 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 section 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 section 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 29 extend radially outward from the rotor disk 28. In many embodiments, each rotor blade 29 in the plurality of rotor blades 29 includes a platform 110, a tip shroud 106, and an airfoil 112 extending radially between the platform 110 and the tip shroud 106. As shown, the tip shrouds 106 of each rotor blade 29 in the plurality of rotor blades 29 abut each other and collectively form a shroud ring 114 that extends continuously circumferentially around the centerline of the gas turbine 10. For example, the shroud 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 shroud ring 114 so that a clearance 108 is defined between the shroud 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 blade 29. In such embodiments, the clearance 108 may be defined between the tip shroud 106 of the rotor blade 29 and the shroud block 35 of the inner turbine casing 33.

[0028] Figure 5 shows an embodiment of the present disclosure of a sealing device 200 for use in a turbomachinery such as the gas turbine 10 described herein. 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.

[0029] 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, 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.

[0030] As shown in Figure 5, 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 29 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.

[0031] Figure 6 shows a cross-sectional view of the sealing device 200 along the circumferential direction C. As shown together in Figures 5 and 6, the sealing device 200 may include a plurality of magnets 212 embedded within a rotating component 204, thereby generating a magnetic field within the clearance 206 that attracts magnetically responsive objects toward the rotating component 204. In exemplary embodiments, the plurality of magnets 212 may be embedded within the rotating component 204 such that the radial outer surface 205 (Figure 6) of the rotating component 204 is coplanar and aligned with the radial outer surfaces 213 of the plurality of magnets 212. In this way, the radial outer surfaces 205, 213 can form a single smooth, continuous surface in the axial direction A. In many embodiments, the rotating component 204 may define grooves or slots 214 in the radial and circumferential directions, in which the plurality of magnets 212 are positioned. In certain embodiments, the plurality of magnets 212 may be fixedly coupled (via brazing or welded joints) to the rotating component 204 within the slots 214. In other embodiments, multiple magnets 212 may be coupled to slots 214 of the rotating component 204 via interference fits.

[0032] Although the multiple magnets 212 are shown in Figure 5 as 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.

[0033] As shown together in Figures 5 and 6, the sealing device 200 may further include a brush seal 208 positioned within the clearance 206 to limit leak flow 218 between the stationary component 202 and the rotating component 204, thereby increasing the efficiency of the gas turbine 10. The leak flow 218 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 218 passing through the clearance 206 can favorably increase the overall efficiency of the gas turbine 10 by minimizing waste.

[0034] In many embodiments, the brush seal 208 may include a frame 215 embedded within a stationary component 202, for example, the frame 215 may be fixedly coupled to a radially defined slot 216 within the stationary component 202. The slot 216 may extend continuously in the circumferential direction C around the axial centerline of the gas turbine 10, so that the brush seal 208 can extend 360° around the centerline of the gas turbine 10. The frame 215 may include a front plate 219, a rear plate 220, and an end plate 222. In exemplary embodiments, the frame 215 may be at least partially formed from an iron-based material (or a combination of iron-based materials) such as iron, nickel, or cobalt, so that the frame 215 responds in the presence of a magnetic field.

[0035] In exemplary embodiments, multiple magnetically responsive filaments 210 may extend from the frame 215 across the clearance 206 to the rotating component 204. As a result, leakage flow 218 can be limited or sealed by the multiple magnetically responsive filaments 210 that at least partially cover the clearance 206. For example, each magnetically responsive filament 210 in the multiple magnetically responsive filaments 210 may extend from a base 224 fixedly coupled to the frame 215 (via a brazed or welded joint) across the clearance 206 to a free end 226 that is movably in contact with the rotating component 204 (or the surface 213 of the magnet 212). For example, the base 224 of each magnetically responsive filament 210 may be fixedly coupled to an end plate 222 of the frame 215. In other embodiments (not shown), the brush seal 208 may not include a frame 215 so that the multiple magnetically responsive filaments 210 extend directly from the slots 216 of the stationary component 202 to the rotating component 204.

[0036] The multiple magnetically responsive filaments 210 may be in the form of wires extending between the stationary component 202 and the rotating component 204 to cover the clearance 206. Each of the multiple magnetically responsive filaments 210 may have a diameter of about 0.0001 to 0.01 inches, or about 0.0001 to 0.001 inches, or about 0.001 to 0.007 inches, or about 0.002 to 0.006 inches, or about 0.003 to 0.005 inches. The relatively small diameter is advantageous in that it allows the magnetically responsive filaments 210 to bend and curve in accordance with the pressure load between the stationary component 202 and the rotating component 204, or in response to the magnetic field of the multiple magnets 212.

[0037] In exemplary embodiments, multiple magnetically responsive filaments 210 may extend at an angle between the stationary component 202 and the rotating component 204 to allow the magnetically responsive filaments 210 to slide along the radially outer surface 213 of the magnet 212 that rotates with the rotating component 204. For example, multiple magnetically responsive filaments 210 may be inclined with respect to the radial R of the gas turbine 10 so that the multiple magnetically responsive filaments slide along the surface of the magnet 212 during the operation of the gas turbine 10. In many embodiments, each magnetically responsive filament 210 may form an angle 228 of about 5 to about 95 degrees with respect to the radial R of the gas turbine 10. In other embodiments, each magnetically responsive filament 210 may form an angle 228 of about 20 to about 70 degrees with respect to the radial R of the gas turbine 10. In various embodiments, each magnetically responsive filament 210 may form an angle 228 of about 30 to about 60 degrees with respect to the radial R of the gas turbine 10. In certain embodiments, each magnetically responsive filament 210 may form an angle 228 of about 35 to about 55 degrees with respect to the radial direction R of the gas turbine 10. The angle 228 advantageously allows the magnetically responsive filament 210 to slide along the surface of the rotating component 204 (or the surface of the magnet 212) without buckling or bending in an unintended manner.

[0038] In many embodiments, the multiple magnetically responsive filaments 210 are at least partially formed from an iron-based material (or a combination of iron-based materials) such as iron, nickel, or cobalt, so that the filaments 210 respond in the presence of a magnetic field. In such embodiments, each magnetically responsive filament 210 may include a magnetic portion 230. For example, the magnetic portion 230 may be formed from an iron-based material and may be positioned between the body of the filament 210 and the free end 226 to pull the free end 226 of the filament 210 toward the magnet 212 by the magnetic field generated by the magnet 212. The magnetic portion 230 may be defined between the body of the filament 210 and the free end 226 such that the magnetic portion 230 constitutes 50% of the total length of the filament 210, or 40% of the total length of the filament 210, or 30% of the total length of the filament 210. In some embodiments, the filament 210 may be formed from a non-ferrous material (e.g., aluminum, copper, lead, tin, titanium, zinc, etc.), and the magnetic portion 230 may include an iron-based or magnetic coating (such as an iron-based metal powder coating or a magnetic powder coating) on ​​the outer surface of the filament 210. In other embodiments, each of the multiple magnetically responsive filaments 210 may be formed entirely from an iron-based material (or a combination of iron-based materials).

[0039] In exemplary embodiments, the multiple magnetically responsive filaments 210 may be attracted to a plurality of magnets 212 embedded within the rotating component, which advantageously enhances the effectiveness of the brush seal 208. For example, the sealing device 200 described herein advantageously allows the multiple magnetically responsive filaments 210 to extend or retract to cover the clearance 206 under any operating conditions of the gas turbine 10. For example, during the startup of the gas turbine 10, the stationary component 202 and the rotating component 204 have not undergone much thermal growth, thereby allowing for a larger clearance 206 in the radial direction R. Under such conditions, the multiple magnetically responsive filaments 210 can be pulled toward the rotating component 204 by the magnetic field generated by the plurality of magnets 212, thereby reducing the angle 228 and extending the radial length of the multiple magnetically responsive filaments 210. In this way, the multiple magnetically responsive filaments 210 can be sealed-engaged (or in contact) with the rotating component 204 by the magnetic field generated by the plurality of magnets 212 under any operating conditions of the gas turbine 10. For example, multiple magnetically responsive filaments 210 may be movable between a minimum thermal growth state of components 202 and 204 where the radial distance between components 202 and 204 is maximum, and a maximum thermal growth state of components 202 and 204 where the radial distance between components 202 and 204 is minimum.

[0040] In many embodiments, the magnets 212 may be permanent magnets, and therefore the magnets 212 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 212 continuously generate their own magnetic fields to which the magnetoresponsive filaments 210 are attracted. In many embodiments, the magnets 212 may be in the form of metallic material pieces having 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 212 may be Alnico magnets, which are permanent magnets mainly composed of a combination of aluminum, nickel, and cobalt, but may also include copper, iron, and titanium. Alnico magnets may be capable of operating at extremely high temperatures, such as above 1000°F.

[0041] Figure 7 shows another embodiment of the sealing assembly 200 in which a rotating component 204 defines a trench 232. The trench 232 may be defined radially inward from the radially outer surface 205 of the rotating component 204, thereby the trench including a front wall 234, a rear wall 236 axially spaced apart from the front wall 234, and a floor 238 extending between the front wall 234 and the rear wall 236. In such an embodiment, a plurality of magnets 212 may be positioned adjacent to either the front wall 234 or the rear wall 236 of the trench 232. For example, a plurality of magnets 212 may be positioned directly adjacent to either the front wall 234 or the rear wall 236 of the trench 232 such that the magnets 212 contact the front wall 234 or the rear wall 236. In exemplary embodiments, the magnet 212 may be positioned against the front wall 234 such that the magnetically responsive filaments 210 are pulled in the opposite direction to the leak flow 218, thereby bundling the filaments together and advantageously limiting more of the leak flow 218 across the filaments 210.

[0042] Figure 8 shows a sealing device 300 for use in turbomachinery, in which multiple magnetically responsive filaments 210 are in a retracted position (not in contact with the rotating component 204). Figure 9 shows a sealing device 300 in which multiple magnetically responsive filaments 210 are in an engaged position (in contact with the rotating component 204). As shown in Figures 8 and 9, the multiple magnets 212 may be a first set of multiple magnets 212 positioned within the rotating component 204, and the sealing assembly may further include a second set of multiple magnets 240 positioned within a stationary component 202 adjacent to the frame 215 of the brush seal 208. For example, the multiple second set of magnets 240 can be mounted directly to the frame 215, such as by being mounted on the end wall 222 of the frame 215.

[0043] In several embodiments, the multiple second magnets 240 may be electromagnets 241. As shown, the electromagnets 241 are configured to have an activated state (Figure 9) in which they emit a magnetic field and a deactivated state (Figure 8) in which they do not emit a magnetic field. When the electromagnets 241 are activated, they emit an electromagnetic field that attracts the multiple magnetically responsive filaments 210 toward the stationary component 202 to a retracted position (Figure 9). For example, the electromagnets 241 may be electrically coupled to a power source 242. The electromagnets 241 can be deactivated by disconnecting the power source 242 when the switch 248 is in the open position (Figure 8). When in the closed position (Figure 9), the switch 248 can connect the electromagnets 241 to the power source 242, thereby enabling the electromagnetic field and causing the multiple magnetically responsive filaments 210 to retract. As shown in Figure 9, when the electromagnet 241 is activated, the filament 210 can move toward the stationary component 204 (without contacting the rotating component 204 and / or the magnet 212) such that a radial gap 246 is defined between the filament 210 and the rotating component 202. The switch 248 can operably communicate with a controller 244, which can open and close the switch, thereby activating or deactivating the electromagnet 241. In this way, the electromagnet 241 may advantageously be able to deactivate the brush seal 208 as needed, such as during the assembly process of the gas turbine 10, during repairs, or under certain operating conditions. The electromagnet 241 can emit a stronger magnetic field than the magnet 212 such that when the electromagnet 241 is activated, the filament 210 moves toward the electromagnet 240 away from the magnet 212.

[0044] In other embodiments, the plurality of second magnets 240 may be a plurality of operable permanent magnets 239 mounted on the frame 215. In such embodiments, each of the plurality of operable permanent magnets 239 can be operated by a controller 244 between a deactivated position (Figure 8) in which the magnet 239 does not emit a magnetic field and an activated position (Figure 9) in which the magnet 239 emits a magnetic field, and each operable permanent magnet includes a cylindrical magnet positioned within a housing, the cylindrical magnet being operable by the controller between the activated and deactivated positions.

[0045] Figure 10 shows a perspective view of a brush seal 208 according to an embodiment of the present disclosure. As shown, the brush seal 208 may include a frame 215, a plurality of magnetically responsive filaments 210 extending from the frame 215, and a second magnet 240 mounted on the frame 215 opposite the filaments 210. In the embodiment shown in Figure 10, the second magnet 240 may be an operable permanent magnet 239. As shown, the operable permanent magnet 239 may include a housing 251, a cylindrical magnet 250 positioned within the housing 251, an iron-based material 254 positioned within the housing 251 and in contact with the frame 215, and a non-ferrous material 252 positioned within the housing 251 opposite the iron-based material 254. The cylindrical magnet 250 may be rotatably operated within the housing 251 by the controller 244 between a deactivated position (Figure 8) in which the cylindrical magnet 250 is positioned so that no magnetic field is generated by the iron-based material 254, and an activated position (Figure 9) in which the cylindrical magnet 250 is positioned so that a magnetic field is generated by the iron-based material 254.

[0046] In various embodiments, the sealing assemblies 200, 300 described herein may utilize 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 assemblies 200, 300 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 such that the frame 215 of the brush seal 208 can be attached to the shroud block 35 (indirectly coupling the brush seal 208 to the inner casing 33). The shroud ring 114 may be a rotating component such that a plurality of magnets 212 can be embedded within the shroud ring 114 of the rotor blades 29. A plurality of filaments 210 may extend across the clearance 108 to advantageously limit and / or prevent combustion gases from passing through the clearance 108. 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]

[0047] 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 nozzles, turbine rotor blades 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 54 Rotor Disc 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 Tip Shroud 108 Clearance 110 platforms 112 Airfoil 114 Shroud Ring 200 sealing devices, sealing assemblies 202 Stationary Components 204 Rotational Components 205 Radial outer surface 206 Clearance 208 Brush Seal 210 Magnetically Responsive Filaments 212 Magnets 213 Radial outer surface, surface 214 grooves or slots 215 frames 216 slots 218 Leakage 219 Front plate 220 Rear Plate 222 End plate, end wall 224 base 226 Free end 228 Bevel 230 Magnetic part 232 Trench 234 Front wall 236 Back wall 238 beds 239 Permanent Magnets 240 The second magnet 241 Electromagnet 242 Power supply 244 controllers 246 Radial gap 248 switches 250 Cylindrical Magnets 251 Housing 252 Non-ferrous materials 254 Iron-based materials 300 sealing devices, sealing assemblies A-axis C Circumferential direction R Radial direction

Claims

1. A sealing device (200) for use in turbomachinery, wherein the sealing device (200) A stationary component (202), A rotating component (204) is provided, wherein the rotating component (204) is spaced apart from the stationary component (202) such that a clearance (206) is defined between the stationary component (202) and the rotating component (204), A plurality of magnets (212) are embedded within the rotating component (204), Brush seal (208) and It is equipped with the brush seal (208), A frame (215) attached to the aforementioned stationary component (202), and A plurality of magnetically responsive filaments (210), each extending from the frame (215) to a free end (226), wherein the plurality of magnetically responsive filaments (210) are attracted to the rotating component (204) by the plurality of magnets (212), and the plurality of magnetically responsive filaments (210) at least partially cover the clearance (206), thereby restricting the flow of fluid (218) across the clearance (206). It is equipped with, A sealing device (200) wherein the plurality of magnets (212) are a plurality of first magnets (212), a plurality of second magnets (240) are embedded in the stationary component (202) adjacent to the frame (215), the plurality of second magnets (240) are configured to be activated and deactivated, and the plurality of magnetically responsive filaments (210) can move to a retracted position toward the stationary component (202) when the plurality of second magnets (240) are activated.

2. The sealing device (200) according to claim 1, wherein the plurality of magnetically responsive filaments (210) are inclined in the circumferential direction (C) with respect to the radial direction (R) of the turbomachinery, such that the plurality of magnetically responsive filaments (210) slide along the surface (213) of the rotating component (204) during the operation of the turbomachinery.

3. The sealing apparatus (200) according to claim 1, wherein the rotating component (204) defines a trench (232) having a front wall (234) and a rear wall (236), and the filament (210) extends into the trench (232) between the front wall (234) and the rear wall (236).

4. The sealing device (200) according to claim 3, wherein the plurality of first magnets (212) are arranged adjacent to either the front wall (234) or the rear wall (236) of the trench (232).

5. The sealing device (200) according to claim 4, wherein the plurality of first magnets (212) are arranged in contact with the front wall (234) of the trench (232) such that the plurality of magnetically responsive filaments (210) are pulled in a direction opposite to the fluid flow (218).

6. The sealing apparatus (200) according to claim 1, wherein the plurality of magnetically responsive filaments (210) are at least partially formed from an iron-based material.

7. The sealing apparatus (200) according to claim 1, wherein the plurality of magnetically responsive filaments (210) are formed of a non-ferrous material that is at least partially coated with an iron-based material.

8. The sealing device (200) according to claim 1, wherein the plurality of second magnets (240) are a plurality of electromagnets (241) that can be controlled by a controller (244).

9. The sealing device (200) according to claim 1, wherein the plurality of second magnets (240) are a plurality of operable permanent magnets (239) attached to the frame (215), each operable permanent magnet (239) includes a cylindrical magnet (250) disposed within a housing (251), and the cylindrical magnet (250) is rotatably operable by a controller (244) between an activated position and a deactivated position.

10. A rotor assembly (19) for a turbomachinery, wherein the rotor assembly (19) A plurality of rotor blades (30) extending radially outward from a rotor disc (28), wherein each rotor blade (30) in the plurality of rotor blades (30) includes a platform (110), a tip shroud (106), and an airfoil portion (112) extending between the platform (110) and the tip shroud (106), and the tip shroud (106) of each rotor blade (30) in the plurality of rotor blades (30) collectively form a shroud ring (114) extending circumferentially (C) around the centerline of the turbomachine, A casing (33) spaced apart from the shroud ring (114), wherein the casing (33) has a plurality of shroud blocks (35) disposed inside it, and a clearance (206) is defined between the shroud ring (114) and the shroud blocks (35), Multiple magnets (212) embedded within the shroud ring (114), Brush seal (208) and It is equipped with the brush seal (208), The frame (215) attached to the casing, and A plurality of magnetically responsive filaments (210), each extending from the frame (215) to a free end (226), wherein the plurality of magnetically responsive filaments (210) are attracted to the shroud ring (114) by the plurality of magnets (212), and the plurality of magnetically responsive filaments (210) at least partially cover the clearance (206), thereby restricting the flow of fluid across the clearance (206). It is equipped with, A rotor assembly (19) wherein the plurality of magnets (212) are a plurality of first magnets (212), a plurality of second magnets (240) are embedded in the casing (33) adjacent to the frame (215), the plurality of second magnets (240) are configured to be activated and deactivated, and the plurality of magnetically responsive filaments (210) can move to a retracted position toward the casing (33) when the plurality of second magnets (240) are activated.

11. The rotor assembly (19) according to claim 10, wherein the plurality of magnetically responsive filaments (210) are inclined circumferentially (C) with respect to the radial direction (R) of the turbomachinery, such that the plurality of magnetically responsive filaments (210) slide along the surface (213) of the shroud ring (114) during the operation of the turbomachinery.

12. The rotor assembly (19) according to claim 10, wherein the shroud ring (114) defines a trench (232) having a front wall (234) and a rear wall (236), and the filament (210) extends into the trench (232) between the front wall (234) and the rear wall (236).

13. The rotor assembly (19) according to claim 12, wherein the plurality of first magnets (212) are arranged adjacent to either the front wall (234) or the rear wall (236) of the trench (232).

14. The rotor assembly (19) according to claim 13, wherein the plurality of first magnets (212) are arranged in contact with the front wall (234) of the trench (232) such that the plurality of magnetically responsive filaments (210) are pulled in a direction opposite to the fluid flow (218).

15. The rotor assembly (19) according to claim 10, wherein the plurality of magnetically responsive filaments (210) are at least partially formed from an iron-based material.

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