Cooling segment and gas turbine including it

Abstract

This invention relates to a cooling segment and a gas turbine including the same, which can improve the cooling performance and cooling efficiency of the cooling segment. [Solution] The present invention relates to a cooling segment and includes a segment body and a cooling channel comprising a first twisted channel provided so as to spirally surround a reference line already set, and a second twisted channel provided so as to spirally surround a reference line in cooperation with the first twisted channel, thereby providing the advantageous effect of improving the cooling performance and cooling efficiency of the cooling segment.

Description

Technical Field

[0001] The present invention relates to a cooling segment and a gas turbine including the same, and more particularly, to a cooling segment capable of improving the cooling performance and cooling efficiency of the cooling segment and a gas turbine including the same.

Background Art

[0002] A turbine is a mechanical device that obtains rotational force by impulse force or reaction force using the flow of a compressible fluid such as steam or gas, and includes a steam turbine using steam and a gas turbine using high-temperature combustion gas.

[0003] A gas turbine is configured to convert thermal energy into mechanical energy by injecting high-temperature and high-pressure combustion gas generated by burning fuel mixed with air compressed to a high pressure by a compressor into a turbine to rotate it.

[0004] More specifically, a gas turbine includes a compressor that compresses air, a combustor that burns compressed air supplied from the compressor and fuel to generate combustion gas, and a turbine that rotates a rotor through turbine blades rotated by the high-temperature and high-pressure combustion gas discharged from the combustor.

[0005] In addition, inside the turbine casing that houses the turbine blades, a plurality of ring segments are provided along the circumferential direction of the turbine casing so as to surround the outer contour of the turbine blades to prevent leakage of high-temperature and high-pressure combustion gas (or prevent leakage of cooling air) and define a tip clearance between the turbine casing and the turbine blades.

[0006] On the other hand, one side of the cooling segment (e.g., ring segment or vane carrier) facing the internal space of the turbine casing is exposed to high-temperature, high-pressure combustion gases. However, the heat load from the combustion gases can cause damage or breakage to the cooling segment, so the cooling segment must be effectively cooled.

[0007] Therefore, conventionally, a method has been proposed in which a cooling channel is provided inside the cooling segment, and the cooling segment is cooled by a cooling medium (for example, air) moving along the cooling channel.

[0008] However, conventionally, it has been difficult to ensure sufficient cooling performance and efficiency of the cooling segment because it is difficult to secure the structural rigidity of the cooling segment and to increase the heat exchange area of ​​the cooling channel (heat exchange area per unit area) beyond a certain level.

[0009] Therefore, in recent years, various studies have been conducted to ensure the structural rigidity of the cooling segment and to improve cooling performance and efficiency, but these are still insufficient, and further development is needed. [Overview of the Initiative] [Problems that the invention aims to solve]

[0010] Embodiments of the present invention aim to provide a cooling segment and a gas turbine including the same that can improve the cooling performance and cooling efficiency of the cooling segment.

[0011] In particular, embodiments of the present invention aim to ensure the structural rigidity of the cooling segment and the heat exchange area of ​​the cooling channel, thereby improving cooling performance and cooling efficiency.

[0012] Furthermore, embodiments of the present invention aim to ensure the structural rigidity of the cooling segment and to maximize the heat exchange area per unit area of ​​the cooling channel.

[0013] Furthermore, embodiments of the present invention aim to reduce costs and improve stability and reliability. The problems that the embodiments aim to solve are not limited to those described herein, and also include the means for solving the problems described later, as well as the objectives and effects that can be understood from the embodiments. [Means for solving the problem]

[0014] According to a preferred embodiment of the present invention for achieving the aforementioned object of the present invention, the cooling segment includes a segment body and a cooling channel including a first twisted channel through which a cooling medium is movably provided inside the segment body and is provided to spirally surround a reference line that has already been set, and a second twisted channel provided to spirally surround a reference line in coordination with the first twisted channel. This is to improve the cooling performance and cooling efficiency of the cooling segment.

[0015] In other words, conventionally, it was difficult to ensure the structural rigidity of the cooling segment and to increase the heat exchange area of ​​the cooling channel (heat exchange area per unit area) beyond a certain point, which made it difficult to ensure sufficient cooling performance and cooling efficiency of the cooling segment. In particular, while expanding the cross-sectional area (e.g., diameter) of the cooling channel can ensure the heat exchange area per unit area of ​​the cooling channel, the larger the cross-sectional area of ​​the cooling channel, the more difficult it becomes to ensure the structural rigidity of the ring segment.

[0016] However, embodiments of the present invention can achieve advantageous effects such as ensuring the structural rigidity of the cooling segment and securing the heat exchange area of ​​the cooling channel, thereby improving cooling performance and cooling efficiency, by forming a cooling channel using a first twisted channel and a second twisted channel having a helical shape.

[0017] Furthermore, embodiments of the present invention can achieve advantageous effects such as ensuring the structural rigidity of the cooling segment and maximizing the heat exchange area per unit area of ​​the cooling channel by forming a cooling channel by intersecting a first twisted channel and a second twisted channel having a helical shape.

[0018] Segment bodies can be manufactured using various methods depending on the required conditions and design specifications. According to a preferred embodiment of the present invention, the segment body is formed by additive manufacturing, and the cooling channel can be integrally provided inside the segment body while the segment body is being formed by additive manufacturing.

[0019] The first twisted channel and the second twisted channel can be provided with various structures depending on the required conditions and design specifications. According to a preferred embodiment of the present invention, the first twisted channel and the second twisted channel can be provided such that they spiral around the reference line, moving in the same direction from one another.

[0020] According to a preferred embodiment of the present invention, the first twisted channel and the second twisted channel can be provided having a circular cross-section. Preferably, the first twisted channel and the second twisted channel can be provided so as to have the same diameter as each other.

[0021] The diameters of the first and second twisted channels can be varied depending on the required conditions and design specifications. According to a preferred embodiment of the present invention, the diameters of the first twisted channel and the second twisted channel can be defined as 0.6 mm to 3 mm.

[0022] When the diameters of the first twist channel and the second twist channel are less than 0.6 mm, it is not only very difficult to process (fabricate) the first twist channel and the second twist channel, but it is also difficult for the cooling medium to move smoothly. When the diameters of the first twist channel and the second twist channel are greater than 3 mm, it is difficult to ensure the structural rigidity of the segment body. Therefore, in the embodiments of the present invention, by defining the diameters of the first twist channel and the second twist channel to be 0.6 mm to 3 mm, the structural rigidity of the segment body can be ensured, and the advantageous effect of smoothly fabricating the first twist channel and the second twist channel can be obtained.

[0023] According to a preferred embodiment of the present invention, the centers of the first twist channel and the second twist channel can be provided to pass through a reference circle defined around a reference line.

[0024] The reference circle can be defined in various sizes according to the required conditions and design specifications. According to a preferred embodiment of the present invention, the diameter of the reference circle can be defined to be 2 mm to 9 mm.

[0025] This is because when the diameter of the reference circle is less than 2 mm, it is difficult to ensure the structural rigidity of the segment body, and when the diameter of the reference circle is greater than 9 mm, it is difficult to sufficiently ensure the heat transfer coefficient of the segment body. Therefore, in the embodiments of the present invention, by defining the diameter of the reference circle that defines the twist trajectories of the first twist channel and the second twist channel to be 2 mm to 9 mm, the structural rigidity of the segment body can be ensured, and the advantageous effect of sufficiently ensuring the heat transfer coefficient of the segment body can be obtained.

[0026] The twist angles of the first twist channel and the second twist channel with respect to the reference line can be variably changed according to the required conditions and design specifications. According to a preferred embodiment of the present invention, the twist angles of the first twist channel and the second twist channel with respect to the reference line can be defined to be 10 degrees to 60 degrees.

[0027] This is because, when the twist angle of the first and second twisted channels with respect to the reference line is less than 10 degrees, the heat exchange area of ​​the first and second twisted channels with respect to the segment body decreases, reducing the heat exchange efficiency. Conversely, when the twist angle of the first and second twisted channels with respect to the reference line is greater than 60 degrees, it becomes difficult to laminate the first and second twisted channels with respect to the segment body, resulting in little improvement in cooling performance. Therefore, in the embodiments of the present invention, by defining the twist angle (θ1, θ2, θ3, θ4) of the first and second twisted channels with respect to the reference line as 10 to 60 degrees, it is possible to sufficiently secure the heat exchange area of ​​the first and second twisted channels with respect to the segment body (cooling performance by the first and second twisted channels), and to obtain the advantageous effect of improving manufacturing efficiency and productivity.

[0028] In another preferred area of ​​the present invention, a gas turbine includes a compressor for drawing in and compressing air, a combustor for mixing the air compressed by the compressor with fuel and burning it, and a turbine including a turbine casing, turbine vanes provided on the inner surface of the turbine casing, turbine blades rotatably provided inside the turbine casing, and a cooling segment provided on the inner surface of the turbine casing to be exposed to combustion gases discharged from the combustor, wherein the cooling segment includes a segment body provided on the inner surface of the turbine casing to be exposed to combustion gases, and a cooling channel provided inside the segment body and provided to spirally surround a predetermined reference line, and a second twisted channel provided to spirally surround a reference line in coordination with the first twisted channel.

[0029] In other preferred areas of the present invention, the cooling segment may include at least one of the following: a vane carrier provided on the inner surface of the turbine casing and supporting the turbine vanes; and a ring segment provided on the inner surface of the turbine casing opposite the turbine blades and spaced apart from the turbine blades.

[0030] In another preferred area of ​​the present invention, the segment body is formed by additive manufacturing, and the cooling channel can be integrally provided inside the segment body during the additive manufacturing process of the segment body.

[0031] In another preferred area of ​​the present invention, the first twisted channel and the second twisted channel can be provided such that they spiral around a reference line, with each other in the same direction.

[0032] According to other preferred fields of the present invention, the first twisted channel and the second twisted channel may be provided having a circular cross-section. According to another preferred area of ​​the present invention, the first twisted channel and the second twisted channel may be provided having the same diameter as each other.

[0033] In other preferred fields of the present invention, the diameters of the first twisted channel and the second twisted channel can be defined as 0.6 mm to 3 mm. According to another preferred area of ​​the present invention, the centers of the first twisted channel and the second twisted channel can be provided so as to pass through a reference circle defined around a reference line.

[0034] According to another preferred area of ​​the present invention, the diameter of the reference circle can be defined as 2 mm to 9 mm. In other preferred fields of the present invention, the twist angles of the first twisted channel and the second twisted channel with respect to a reference line can be defined as 10 to 60 degrees. [Effects of the Invention]

[0035] As mentioned above, according to the present invention, it is possible to obtain the advantageous effect of improving the cooling performance and cooling efficiency of the cooling segment. In particular, according to the present invention, it is possible to obtain advantageous effects such as ensuring the structural rigidity of the cooling segment and ensuring the heat exchange area of ​​the cooling channel, thereby improving cooling performance and cooling efficiency.

[0036] Furthermore, according to the present invention, it is possible to obtain the advantageous effects of ensuring the structural rigidity of the cooling segment and maximizing the heat exchange area per unit area of ​​the cooling channel. Furthermore, according to the present invention, it is possible to obtain advantageous effects such as cost reduction and improved stability and reliability. [Brief explanation of the drawing]

[0037] [Figure 1] This is a diagram illustrating a gas turbine according to an embodiment of the present invention. [Figure 2] This diagram illustrates a cooling segment in a gas turbine according to an embodiment of the present invention. [Figure 3] This diagram illustrates a cooling segment in a gas turbine according to an embodiment of the present invention. [Figure 4] This diagram illustrates a cooling channel as a cooling segment according to an embodiment of the present invention. [Figure 5] This diagram illustrates a cooling channel as a cooling segment according to an embodiment of the present invention. [Figure 6] This figure illustrates a modified example of a cooling channel as a cooling segment according to an embodiment of the present invention. [Figure 7] This figure illustrates a modified example of a cooling channel as a cooling segment according to an embodiment of the present invention. [Figure 8] This figure illustrates a modified example of a cooling channel as a cooling segment according to an embodiment of the present invention. [Figure 9] This figure illustrates a modified example of a cooling channel as a cooling segment according to an embodiment of the present invention. [Figure 10]This figure illustrates the temperature of a cooling segment according to an embodiment of the present invention, based on the twist angle of the twisted flow path with respect to a reference line. [Figure 11] This figure illustrates the temperature of a cooling segment according to an embodiment of the present invention, based on the twist angle of the twisted flow path with respect to a reference line. [Modes for carrying out the invention]

[0038] Preferred embodiments of the present invention will be described in detail below with reference to the attached drawings. However, the technical concept of the present invention is not limited to the embodiments described, but can be realized in various forms that are different from each other, and within the scope of the technical concept of the present invention, one or more of its components can be selectively combined and substituted between embodiments.

[0039] Furthermore, terms used in embodiments of the present invention (including technical and scientific terms) shall be interpreted as generally understood by a person of ordinary skill in the art to which the present invention belongs, unless explicitly defined otherwise. Terms that are commonly used, such as those defined in dictionaries, may be interpreted considering their meaning in the context of the relevant art. Furthermore, the terms used in the embodiments of the present invention are for illustrative purposes only and do not limit the present invention.

[0040] In this specification, the singular form includes the plural form unless otherwise specified in the text, and when it is written as "A and / or at least one of B and C," it may include one or more of all possible combinations of A, B, and C.

[0041] Furthermore, when describing the components of the embodiments of the present invention, terms such as first, second, A, B, (a), (b), etc., can be used. Such terminology is merely used to distinguish one component from another, and does not limit the nature, hierarchy, or order of that component.

[0042] Furthermore, when it is stated that one component is “connected,” “joined,” or “connected” to another component, this may include not only cases where the component is directly connected, joined, or connected to the other component, but also cases where it is “connected,” “joined,” or “connected” by another component that exists between the component and the other component.

[0043] Furthermore, when it is stated that a component is formed or positioned "above" or "below" each component, "above" or "below" includes not only cases where two components are in direct contact with each other, but also cases where one or more other components are formed or positioned between two components. Also, when expressed as "above" or "below," it can include not only the upward direction but also the downward direction, relative to one component.

[0044] Referring to Figures 1 to 11, a cooling segment (CS) according to an embodiment of the present invention includes a segment body 342 and a cooling channel 344 which includes a first twisted channel 344a provided so as to spirally surround a predetermined reference line (CL) and a second twisted channel 344b provided so as to spirally surround the reference line (CL) in coordination with the first twisted channel 344a.

[0045] The cooling segment (CS) is applicable to a variety of objects depending on the required conditions and design specifications, and the present invention is not limited or restricted by the type and structure of the object to which the cooling segment (CS) is applied.

[0046] The following describes an example in which a cooling segment (CS) according to an embodiment of the present invention is applied to a gas turbine 10 including a compressor 100, a combustor 200, and a turbine 300.

[0047] For reference, the gas turbine 10 is configured to inhale atmospheric air, compress it to a high pressure, burn fuel in a constant-pressure environment to release thermal energy, and then expand this high-temperature combustion gas to convert it into kinetic energy.

[0048] Referring to Figures 1 to 3, according to a preferred embodiment of the present invention, the gas turbine 10 includes a compressor for drawing in and compressing air, a combustor for mixing the air compressed by the compressor with fuel and burning it, and a turbine including a turbine casing, turbine vanes provided on the inner surface of the turbine casing, turbine blades rotatably provided inside the turbine casing, and a cooling segment (CS) provided on the inner surface of the turbine casing so as to be exposed to combustion gases discharged from the combustor, wherein the cooling segment (CS) includes a segment body 342 provided on the inner surface of the turbine casing so as to be exposed to combustion gases, and a cooling channel 344 provided inside the segment body 342 and provided so as to spirally surround an already set reference line (CL), and a second twisted channel 344b provided so as to spirally surround the reference line (CL) in coordination with the first twisted channel 344a.

[0049] The compressor 100 is designed to draw in air from the outside and compress it. For example, the compressor 100 can supply compressed air compressed by the compressor blades 110 to the combustor 200, and can supply cooling air to the high-temperature region of the gas turbine 10 that requires cooling.

[0050] Various compressors 100 can be used depending on the required conditions and design specifications, and the present invention is not limited or restricted by the type and structure of the compressor 100.

[0051] For example, the compressor 100 can be designed as a centrifugal compressor or an axial compressor, with centrifugal compressors used in small gas turbines and multi-stage axial compressors used in large gas turbines.

[0052] According to a preferred embodiment of the present invention, the compressor 100 may include compressor blades 110 that rotate together with the rotor 600, and compressor vanes 120 provided in a compressor casing (not shown) to align the airflow into the compressor blades 110.

[0053] For reference, the rotor 600 may include a compressor rotor disc 610 housed in a compressor casing (not shown), a turbine rotor disc 630 housed in a turbine casing 310, a torque tube 620 housed in a combustor casing (not shown) connecting the compressor rotor disc 610 and the turbine rotor disc 630, tie rods 640 fastening the compressor rotor disc 610, the torque tube 620, and the turbine rotor disc 630, and fixing nuts (not shown).

[0054] Multiple compressor rotor disks 610 (for example, 14 disks) can be formed, and these multiple compressor rotor disks 610 can be arranged along the axial direction of the rotor 600. In other words, the compressor rotor disks 610 can be formed in multiple stages.

[0055] Furthermore, each compressor rotor disk 610 is formed in a substantially disc shape, and compressor blade coupling slots (not shown) for coupling with compressor blades 110, which will be described later, can be formed on the outer circumference of the compressor rotor disk 610.

[0056] The turbine rotor disc 630 can be formed similarly to the compressor rotor disc 610. That is, multiple turbine rotor discs 630 can be formed, and the multiple turbine rotor discs 630 can be arranged in multiple stages along the axial direction of the rotor 600.

[0057] The turbine rotor disc 630 is formed in a substantially disc shape, and turbine blade 320 coupling slots (not shown) for coupling with the turbine blades 320, which will be described later, can be formed on the outer circumference of the turbine rotor disc 630.

[0058] The torque tube 620 is a torque transmission member that transmits the rotational force of the turbine rotor disc 630 to the compressor rotor disc 610. One end of the tube can be fastened to the compressor rotor disc located at the downstream end in the direction of airflow among the multiple compressor rotor discs 610, and the other end can be fastened to the turbine rotor disc 630 located at the upstream end in the direction of combustion gas flow among the multiple turbine rotor discs 630.

[0059] Projections (not shown) are formed at one end and the other end of the torque tube 620, and grooves (not shown) that engage with the projections are formed in the compressor rotor disc 610 and the turbine rotor disc 630, respectively, thereby constraining the relative rotation of the torque tube 620 with respect to the compressor rotor disc 610 and the turbine rotor disc 630.

[0060] The torque tube 620 can be formed in a nearly hollow cylindrical shape so that air supplied from the compressor 100 can flow through the torque tube 620 to the turbine 300.

[0061] Preferably, the torque tube 620 is formed to have properties that make it resistant to deformation and warping, given the characteristics of the gas turbine 10 which is operated continuously for a long period of time, and can be configured to be easily assembled and disassembled for easy maintenance.

[0062] The tie rod 640 is formed to penetrate multiple compressor rotor discs 610, torque tubes 620, and multiple turbine rotor discs 630. One end is fastened into the compressor rotor disc 610 located at the upstream end in the direction of airflow, and the other end protrudes on the opposite side of the compressor 100 with respect to the turbine rotor disc 630 located at the downstream end in the direction of combustion gas flow, and can be fastened to a fixing nut.

[0063] The fixing nut pressurizes the turbine rotor disc 630 located at the downstream end toward the compressor 100, reducing the distance between the compressor rotor disc 610 located at the upstream end and the turbine rotor disc 630 located at the downstream end. This allows the multiple compressor rotor discs 610, torque tubes 620, and multiple turbine rotor discs 630 to be compressed in the axial direction of the rotor 600. As a result, the axial movement and relative rotation of the multiple compressor rotor discs 610, torque tubes 620, and multiple turbine rotor discs 630 can be restrained.

[0064] In the embodiments of the present invention described above and illustrated, an example was given in which the tie rods penetrate the centers of multiple compressor rotor discs, torque tubes, and multiple turbine rotor discs 630. However, according to other embodiments of the present invention, it is also possible to provide separate tie rods on the compressor side and on the turbine side, respectively. In another embodiment, it is also possible to configure the multiple tie rods to be arranged radially along the circumferential direction. In this configuration, the rotor 600 is rotatably supported at both ends by bearings, and one end can be connected to the drive shaft of a generator.

[0065] Multiple compressor blades 110 are formed, and the multiple compressor blades 110 are formed in multiple stages along the axial direction of the rotor 600, and the multiple compressor blades 110 can be formed radially along the rotational direction of the rotor 600 for each stage.

[0066] The root portion (not shown) of the compressor blade 110 is coupled to a compressor blade coupling slot (not shown) of the compressor rotor disk 610, and the root portion can be formed in a fir-tree shape to prevent the compressor blade 110 from detaching from the compressor blade coupling slot in the radial direction of rotation of the rotor 600. In this case, the compressor blade coupling slot can similarly be formed in a fir-tree shape to correspond to the root portion of the compressor blade 110.

[0067] In the embodiments of the present invention described above and illustrated, an example was given in which the compressor blade root portion and the compressor blade coupling slot were formed in a dovetail shape. However, according to other embodiments of the present invention, the compressor blade root portion and the compressor blade coupling slot can also be formed in a dovetail shape or other shapes. In another embodiment, the compressor blade can be fastened to the compressor rotor disk using a separate fastening device such as a key or bolt.

[0068] The compressor rotor disk 610 and the compressor blades 110 can typically be coupled in a tangential or axial configuration. In the embodiment of the present invention, the compressor blade root is formed in a so-called axial configuration, as described above, where it is inserted into the compressor blade coupling slot along the axial direction of the rotor 600.

[0069] Preferably, multiple compressor blade coupling slots are formed, and the multiple compressor blade coupling slots can be arranged radially along the circumferential direction of the compressor rotor disk.

[0070] Multiple compressor vanes 120 are formed, and the multiple compressor vanes 120 can be formed in multiple stages along the axial direction of the rotor 600. Here, the compressor vanes 120 and compressor blades 110 can be arranged alternately with respect to the direction of airflow.

[0071] Furthermore, the multiple compressor vanes 120 can be formed radially along the rotation direction of the rotor 600 for each stage. As an example, at least some of the multiple compressor vanes 120 can be mounted to rotate within a defined range for purposes such as adjusting the amount of air flowing in.

[0072] The combustor 200 is configured to mix compressed air supplied from the compressor 100 with fuel and perform isobaric combustion to generate high-energy combustion gas. Various types of combustors 200 that mix compressed air with fuel and burn it can be used as the combustor 200, and the present invention is not limited or restricted by the type and structure of the combustor 200.

[0073] As an example, multiple combustors 200 may be provided, and the multiple combustors 200 may be arranged in a combustor casing (not shown) along the rotational direction of the rotor 600.

[0074] The combustor 200 may include a liner (not shown) into which compressed air from the compressor 100 flows, and a transition piece (not shown) located behind the liner that guides the combustion gases to the turbine 300. The liner and transition piece may form a combustion chamber inside, and a sleeve may be positioned to surround the liner and transition piece, forming an annular fluid space between them.

[0075] The combustor 200 may also include a fuel injection nozzle (not shown) located in front of the liner to mix and inject compressed air supplied from the compressor 100 with fuel, and a spark plug (not shown) located on the wall of the liner to ignite the mixed compressed air and fuel in the combustion chamber of the liner. The combusted gas is then discharged to the turbine 300 to generate rotation.

[0076] In this context, cooling the liner and transition piece, which are exposed to high-temperature, high-pressure combustion gases, is important for increasing the durability of the combustor 200. For this purpose, cooling holes (not shown) can be formed in the sleeve, and the liner and transition piece can be cooled by compressed air flowing in through the cooling holes and colliding vertically with the outer walls of the liner and transition piece.

[0077] More specifically, the compressed air flowing in from the compressor 100 flows into the annular space through cooling holes formed in the sleeve to cool the liner and transition piece, and can flow along the annular space forward of the liner and into the fuel injection nozzle.

[0078] Furthermore, a de-swirler, which acts as a guide vane to adjust the airflow angle of the air flowing into the combustor 200 to the design airflow angle, may be provided between the compressor 100 and the combustor 200.

[0079] The high-temperature, high-pressure exhaust gas generated in the combustor 200 is supplied to the turbine 300, where the exhaust gas undergoes adiabatic expansion and collides with multiple blades arranged radially around the turbine's rotating shaft, applying a reaction force. This converts the thermal energy of the exhaust gas into mechanical energy that rotates the shaft.

[0080] A portion of the mechanical energy generated by the turbine 300 is used as the energy necessary to compress air in the compressor 100, while the remainder can be used as useful energy, such as to drive a generator to produce electricity.

[0081] The turbine 300 can be constructed similarly to the compressor 100. The turbine 300 may include turbine blades 320 that rotate together with the rotor 600, and turbine vanes 330 that are fixedly mounted to the turbine casing 310 to align the airflow into the turbine blades 320.

[0082] For example, multiple turbine blades 320 may be formed, and the multiple turbine blades 320 may be formed in multiple stages along the axial direction of the rotor 600, and the multiple turbine blades 320 may be formed radially along the rotational direction of the rotor 600 for each stage.

[0083] Specifically, the turbine blade 320 may include a plate-shaped turbine blade 320 platform portion (not shown), a turbine blade 320 root portion (not shown) extending centrifugally from the turbine blade 320 platform portion in the radial direction of rotation of the rotor 600, and a turbine blade 320 airfoil portion (not shown) extending centrifugally from the turbine blade 320 platform portion in the radial direction of rotation of the rotor 600.

[0084] The turbine blade 320 platform section can be in contact with adjacent turbine blade 320 platform sections and can play a role in maintaining the spacing between turbine blade 320 airfoil sections.

[0085] The root portion of the turbine blade 320 is coupled to the turbine blade 320 coupling slot of the turbine rotor disk 630, and the root portion can be formed in a fir-tree shape to prevent the turbine blade 320 from detaching from the turbine blade 320 coupling slot in the radial direction of rotation of the rotor 600. In this case, the turbine blade 320 coupling slot can similarly be formed in a fir-tree shape to correspond to the root portion of the turbine blade 320. As described above, the root portion of the turbine blade 320 can be formed in a so-called axial type configuration, which is inserted into the turbine blade 320 coupling slot along the axial direction of the rotor 600.

[0086] The turbine blade 320 airfoil section is formed to have an optimized blade shape according to the specifications of the gas turbine 10, and may include a leading edge located upstream in the direction of combustion gas flow, to which the combustion gas is injected, and a trailing edge located downstream in the direction of combustion gas flow, to which the combustion gas is ejected.

[0087] Multiple turbine vanes 330 are formed, and these multiple turbine vanes 330 can be formed in multiple stages along the axial direction of the rotor 600. Here, the turbine vanes 330 and turbine blades 320 can be arranged alternately with respect to the direction of airflow. Furthermore, the multiple turbine vanes 330 can be formed radially along the rotational direction of the rotor 600 for each stage.

[0088] For example, the turbine vane 330 can be fixedly attached (supported) within the turbine housing by a vane carrier 350, which is an endwall connected to the inner and outer ends of the turbine vane 330.

[0089] Unlike the compressor 100, the turbine 300 is in contact with high-temperature, high-pressure combustion gases and therefore requires cooling to prevent damage such as deterioration. For this purpose, a cooling line (not shown) may be included to extract compressed air from a portion of the compressor 100 and supply it to the turbine 300.

[0090] For example, the cooling line can extend to the outside of the compressor casing (external line) or through the inside of the rotor 600 (internal line), and it is also possible to use both external and internal lines.

[0091] The cooling line communicates with a turbine blade cooling channel (not shown) formed inside the turbine blade 320, allowing the turbine blade 320 to be cooled by cooling air. Furthermore, the turbine blade cooling channel communicates with a turbine blade film cooling hole formed on the surface of the turbine blade 320, allowing cooling air to be supplied to the surface of the turbine blade 320, thereby enabling so-called film cooling by the cooling air. The turbine vanes 330 can also be configured to be cooled by cooling air supplied from the cooling line, similar to the turbine blades 320.

[0092] On the other hand, the turbine 300 requires a gap between the tip of the turbine blade 320 and the inner surface of the turbine casing 310 so that the turbine blade 320 can rotate smoothly.

[0093] However, the wider the gap between the blade tip of the turbine blade 320 and the inner surface of the turbine casing 310, the more advantageous it is in preventing interference between the turbine blade 320 and the turbine casing 310, but the more disadvantageous it is in terms of combustion gas leakage. The opposite is true if the gap is narrow.

[0094] In other words, the flow of combustion gas injected from the combustor 200 can be divided into a main flow that passes through the turbine blades 320 and a leakage flow that passes through the gap between the turbine blades 320 and the turbine casing 310. The wider the gap, the greater the leakage flow and the lower the efficiency of the gas turbine 10, but interference between the turbine blades 320 and the turbine casing 310 due to thermal deformation and the resulting damage can be prevented. On the other hand, the narrower the gap (the gap between the blade tips of the turbine blades 320 and the inner circumferential surface of the turbine casing 310), the less leakage flow there is and the higher the efficiency of the gas turbine 10 can be, but interference between the turbine blades 320 and the turbine casing 310 due to thermal deformation and the resulting damage can occur.

[0095] Preferably, the gas turbine 10 may include a ring segment 340 to ensure a suitable gap that prevents interference and resulting damage between the turbine blades 320 and the turbine casing 310, and minimizes the reduction in gas turbine efficiency.

[0096] Referring to Figures 2 and 3, the ring segments 340 are provided on the inner circumferential surface of the turbine casing 310 so as to surround the turbine blades 320. Specifically, multiple ring segments 340 are attached to the inner wall of the turbine casing 310, and the multiple ring segments 340 are arranged continuously along the circumferential direction (circumferential direction) of the turbine casing 310, forming a substantially annular shape. The multiple annular ring segments 340 surround the turbine blades 320 from the outside, preventing combustion gas leakage. That is, the multiple annular ring segments 340 can be formed in multiple stages in the longitudinal direction of the turbine central axis, corresponding to the positions of the turbine blades 320, and can be arranged alternately with the turbine vanes 330.

[0097] As an example, the ring segment 340 may include a shielding plate (not shown) facing the inner wall of the turbine casing 310 and extending along the rotational direction of the rotor 600, and a pair of hook portions (not shown) protruding from the shielding plate toward the turbine casing 310. The shielding plate may be formed in a substantially rectangular plate shape, and the hook portions may protrude from the outer surface of the shielding plate toward the turbine casing 310 so as to be bent radially toward the turbine, and be inserted into grooves formed in the turbine casing 310.

[0098] Furthermore, since high-temperature, high-pressure combustion gases pass through the turbine casing 310, the ring segment 340, particularly the portion of the ring segment 340 facing the internal space of the turbine casing 310 (the inner circumferential surface of the ring segment), may be damaged due to the thermal load. Therefore, to prevent this, multiple cooling channels 344 can be provided in the ring segment 340.

[0099] The cooling segment (CS) is provided on the inner surface of the turbine casing 310 so as to be exposed to the combustion gases discharged from the combustor 200. In embodiments of the present invention, a cooling segment (CS) can be defined as a component that is exposed to combustion gases inside the turbine casing 310 and therefore requires cooling.

[0100] The type and structure of the cooling segment (CS) can be varied in many ways depending on the required conditions and design specifications, and the present invention is not limited or restricted by the type and structure of the cooling segment (CS).

[0101] According to a preferred embodiment of the present invention, the cooling segment (CS) may include at least one of the following: a vane carrier 350 provided on the inner surface of the turbine casing 310 and supporting the turbine vanes 330; and a ring segment 340 provided on the inner surface of the turbine casing 310, facing the turbine blades 320 and spaced apart from the turbine blades 320.

[0102] The following example illustrates the application of the ring segment 340 as the cooling segment (CS). According to a preferred embodiment of the present invention, the ring segment 340 may include a segment body 342 and a cooling channel 344 which includes a first twisted channel 344a provided so as to spirally surround an already established reference line (CL) and a second twisted channel 344b provided so as to spirally surround the reference line (CL) in coordination with the first twisted channel 344a.

[0103] The segment body 342 can be provided with various structures depending on the required conditions and design specifications, and the present invention is not limited or restricted by the structure and form of the segment body 342.

[0104] As an example, the segment body 342 may include a shielding plate (not shown) facing the inner wall of the turbine casing 310 and extending along the rotational direction of the rotor 600, and a pair of hook portions (not shown) protruding from the shielding plate toward the turbine casing 310.

[0105] Referring to Figures 3 to 5, the cooling channel 344 is provided inside the segment body 342 so as to include a first twisted channel 344a and a second twisted channel 344b.

[0106] The location of the cooling channels 344 in the segment body 342 can be varied in many ways depending on the required conditions and design specifications, and the present invention is not limited or restricted by the location and number of cooling channels 344.

[0107] The following description will use an example in which a plurality of cooling channels 344 are provided in a shielding plate constituting a segment body 342 along the axial direction of the turbine 300. According to other embodiments of the present invention, it is also possible to form cooling channels along the circumferential direction or other directions of the turbine. In another embodiment, it is also possible to form cooling channels in the hook portion or other parts constituting the segment body.

[0108] For example, one end of the cooling channel 344 (e.g., one end of the first twisted channel and one end of the second twisted channel) can communicate with a cooling line extending outside the compressor casing, and a cooling medium (e.g., air) supplied along the cooling line can cool the segment body 342 as it moves along the cooling channel 344.

[0109] The first twisted channel 344a and the second twisted channel 344b are provided so as to spirally surround an already established reference line (CL). The reference line (CL) can be defined according to the required conditions and design specifications.

[0110] As an example, the reference line (CL) can be defined as a straight line, the first twisted channel 344a can be configured to continuously surround the reference line (CL) having a straight line in a spiral shape, and the second twisted channel 344b can be configured to continuously surround the reference line (CL) having a straight line in a spiral shape so as to intersect with the first twisted channel 344a.

[0111] In the embodiments of the present invention described above and illustrated, an example was given in which the reference line (CL) is defined as a straight line. However, according to other embodiments of the present invention, the reference line can also be defined as a curved or other shape.

[0112] The segment body 342 can be manufactured using various methods depending on the required conditions and design specifications. According to a preferred embodiment of the present invention, the segment body 342 is formed by additive manufacturing, and the cooling channel 344 can be integrally provided inside the segment body 342 while the segment body 342 is being formed by additive manufacturing. For example, the segment body 342 can be manufactured using a conventional 3D printing method. For example, the segment body 342 can be made of a conventional metal material.

[0113] The first twisted channel 344a and the second twisted channel 344b can be provided with various structures depending on the required conditions and design specifications, and the present invention is not limited or restricted by the structure and form of the first twisted channel 344a and the second twisted channel 344b.

[0114] According to a preferred embodiment of the present invention, the first twisted channel 344a and the second twisted channel 344b can be provided so as to spirally surround the reference line (CL) with respect to the reference line (CL) in the same direction from respect to

[0115] As an example, the first twisted channel 344a and the second twisted channel 344b can each be provided so as to spirally surround the reference line (CL) in a clockwise direction, centered on the reference line (CL).

[0116] In another embodiment of the present invention, either the first twisted channel or the second twisted channel may be configured to spirally surround the reference line in a clockwise direction, and the other of the first twisted channel or the second twisted channel may be configured to spirally surround the reference line in a counterclockwise direction, centered on the reference line.

[0117] According to a preferred embodiment of the present invention, the first twisted channel 344a and the second twisted channel 344b can be provided having a circular cross-section. Preferably, the first twisted channel 344a and the second twisted channel 344b can be provided to have the same diameter (D1) as each other.

[0118] In other embodiments of the present invention, the first twisted channel and the second twisted channel may be configured to have different diameters or different cross-sectional areas. In another embodiment, the first twisted channel and the second twisted channel may be configured to have a square cross-section, a triangular cross-section, or other cross-sectional shape.

[0119] The diameters of the first twisted channel 344a and the second twisted channel 344b can be varied in various ways depending on the required conditions and design specifications, and the present invention is not limited or restricted by the diameters of the first twisted channel 344a and the second twisted channel 344b.

[0120] According to a preferred embodiment of the present invention, the diameters of the first twisted channel 344a and the second twisted channel 344b can be defined as 0.6 mm to 3 mm.

[0121] This is because, when the diameters of the first twisted passage 344a and the second twisted passage 344b are smaller than 0.6 mm, not only is it extremely difficult to process (manufacture) the first twisted passage 344a and the second twisted passage 344b, but it is also difficult to ensure the smooth movement of the cooling medium. When the diameters of the first twisted passage 344a and the second twisted passage 344b are larger than 3 mm, it is difficult to ensure the structural rigidity of the segment body 342. Therefore, the embodiments of the present invention define the diameters of the first twisted passage 344a and the second twisted passage 344b as 0.6 mm to 3 mm, thereby obtaining the advantageous effect of ensuring the structural rigidity of the segment body 342 and smoothly manufacturing the first twisted passage 344a and the second twisted passage 344b.

[0122] According to a preferred embodiment of the present invention, the centers of the first twisted channel 344a and the second twisted channel 344b can be provided so as to pass through a reference circle defined around a reference line (CL).

[0123] Here, the centers of the first twisted channel 344a and the second twisted channel 344b passing through a reference circle defined around the reference line (CL) can be defined as the first twisted channel 344a and the second twisted channel 344b having the same helical radius (D2 / 2) around the reference line (CL).

[0124] Here, the reference circle can be defined to various sizes depending on the required conditions and design specifications, and the present invention is not limited or restricted by the size of the reference circle.

[0125] According to a preferred embodiment of the present invention, the diameter (D2) of the reference circle can be defined as 2 mm to 9 mm. This is because, when the diameter of the reference circle (D2) is less than 2 mm, it is difficult to ensure the structural rigidity of the segment body 342, and when the diameter of the reference circle is greater than 9 mm, it is difficult to ensure a sufficient heat transfer coefficient of the segment body 342. Therefore, in the embodiment of the present invention, by defining the diameter of the reference circle (D2) that defines the twist trajectories of the first twisted flow path 344a and the second twisted flow path 344b as 2 mm to 9 mm, it is possible to obtain the advantageous effect of ensuring the structural rigidity of the segment body 342 and ensuring a sufficient heat transfer coefficient of the segment body 342.

[0126] The twist angles of the first twisted channel 344a and the second twisted channel 344b with respect to the reference line (CL) can be varied in various ways depending on the required conditions and design specifications, and the present invention is not limited or restricted by the twist angles of the first twisted channel 344a and the second twisted channel 344b with respect to the reference line (CL).

[0127] According to a preferred embodiment of the present invention, the twist angles (θ1, θ2, θ3, θ4) of the first twisted channel 344a and the second twisted channel 344b with respect to the reference line (CL) can be defined as 10 to 60 degrees.

[0128] As an example, referring to Figure 6, the twist angle (θ1) of the first twisted channel 344a and the second twisted channel 344b with respect to the reference line (CL) can be defined as 10 degrees.

[0129] As another example, referring to Figure 7, the twist angle (θ2) of the first twisted channel 344a and the second twisted channel 344b with respect to the reference line (CL) can be defined as 30 degrees.

[0130] As another example, referring to Figure 8, the twist angle (θ3) of the first twisted channel 344a and the second twisted channel 344b with respect to the reference line (CL) can be defined as 45 degrees.

[0131] As yet another example, referring to Figure 9, the twist angle (θ4) of the first twisted channel 344a and the second twisted channel 344b with respect to the reference line (CL) can be defined as 60 degrees.

[0132] This means that when the twist angle of the first twisted channel 344a and the second twisted channel 344b with respect to the reference line (CL) is less than 10 degrees, the heat exchange area of ​​the first twisted channel 344a and the second twisted channel 344b with respect to the segment body 342 decreases, and the heat exchange efficiency decreases. When the twist angle of the first twisted channel 344a and the second twisted channel 344b with respect to the reference line (CL) is greater than 60 degrees, the stacking of the first twisted channel 344a and the second twisted channel 344b with respect to the segment body 342 decreases. Because manufacturing is difficult and the improvement in cooling performance is not significant, the embodiments of the present invention define the twist angles (θ1, θ2, θ3, θ4) of the first twisted channel 344a and the second twisted channel 344b with respect to the reference line (CL) as 10 to 60 degrees. This ensures a sufficient heat exchange area (cooling performance by the first twisted channel and the second twisted channel) for the first twisted channel 344a and the second twisted channel 344b with respect to the segment body 342, and also provides the advantageous effect of improving manufacturing efficiency and productivity.

[0133] On the other hand, Figures 10 and 11 are diagrams illustrating the temperature of the cooling segment (CS) due to the twist angle of the first twisted channel 344a and the second twisted channel 344b with respect to the reference line (CL).

[0134] For reference, Figures 10 and 11 are graphs showing the results of the thermal fluid dynamics (CFD) analysis of the cooling segment (CS) based on the twist angles of the first twisted channel 344a and the second twisted channel 344b relative to the baseline (CL).

[0135] Referring to Figures 10 and 11, it can be seen that the temperature of the cooling segment (CS) decreases as the twist angle of the first twisted channel 344a and the second twisted channel 344b relative to the reference line (CL) increases.

[0136] In particular, in the case of a cooling segment (CS) to which a cooling channel 344 is applied, defined as having a twist angle (θ4) of 60 degrees between the first twisted channel 344a and the second twisted channel 344b with respect to a reference line (CL), a sufficient heat exchange area between the first twisted channel 344a and the second twisted channel 344b and the segment body 342 can be secured. As a result, it can be confirmed that the temperature is significantly lower compared to a conventional cooling segment (CS) to which a conventional circular tubular cooling channel 344 (for example, a circular tubular channel with a wave shape) is applied. This shows that increasing the heat exchange area between the first twisted channel 344a and the second twisted channel 344b and the segment body 342 is more advantageous for improving the cooling performance and cooling efficiency of the cooling segment (CS).

[0137] Although the above description has focused on embodiments, these are merely examples and do not limit the present invention. Anyone with ordinary skill in the art to which the present invention belongs will understand that various modifications and applications not exemplified above are possible, without departing from the essential characteristics of these embodiments. For example, each component specifically shown in the embodiments can be modified and implemented. Such differences related to modifications and applications should be interpreted as being within the scope of the present invention as defined in the appended claims. [Explanation of symbols]

[0138] 10: Gas Turbine 20: Seal Assembly 100: Compressor 110: Compressor blade 120: Compressor vanes 200: Combustor 300: Turbine 310: Turbine casing 320: Turbine Blade 330: Turbine vanes 340: Ring segment 342: Segment Body 344: Cooling channel 344a: First twisted channel 344b: Second twisted channel 350: Vane Carrier 600: Rotor 610: Compressor rotor disc 620: Torque Tube 630: Turbine rotor disc 640: Tie rod

Claims

1. Segment body and A cooling channel comprising a first twisted channel provided so as to spirally surround a reference line already set, and a second twisted channel provided so as to spirally surround the reference line in cooperation with the first twisted channel, A cooling segment, including the cooling segment.

2. The cooling segment according to claim 1, wherein the segment body is formed by additional manufacturing, and the cooling channel is integrally provided inside the segment body while the segment body is being formed by the additional manufacturing.

3. The cooling segment according to claim 1, wherein the first twisted channel and the second twisted channel are provided so as to spirally surround the reference line with respect to the reference line, each in the same direction.

4. The cooling segment according to any one of claims 1 to 3, wherein the first twisted channel and the second twisted channel are provided to have a circular cross-section.

5. The cooling segment according to claim 4, wherein the first twisted channel and the second twisted channel are provided to have the same diameter as each other.

6. The cooling segment according to claim 5, wherein the diameters of the first twisted channel and the second twisted channel are defined as 0.6 mm to 3 mm.

7. The cooling segment according to claim 5, wherein the centers of the first twisted channel and the second twisted channel are provided to pass through a reference circle defined around the reference line.

8. The cooling segment according to claim 7, wherein the diameter of the reference circle is defined as 2 mm to 9 mm.

9. The cooling segment according to claim 5, wherein the twist angles of the first twisted flow path and the second twisted flow path with respect to the reference line are defined as 10 degrees to 60 degrees.

10. A compressor that takes in air and compresses it, A combustor that mixes the air compressed by the compressor with fuel and burns it, A turbine including a turbine casing, turbine vanes provided on the inner surface of the turbine casing, turbine blades rotatably provided inside the turbine casing, and cooling segments provided on the inner surface of the turbine casing so as to be exposed to combustion gases discharged from the combustor, Includes, The cooling segment is A segment body provided on the inner surface of the turbine casing so as to be exposed to the combustion gas, A cooling channel including a first twisted channel provided inside the segment body and arranged to spirally surround an already established reference line, and a second twisted channel provided to spirally surround the reference line in cooperation with the first twisted channel, A gas turbine, including

11. The cooling segment is The gas turbine according to claim 10, comprising at least one of a vane carrier provided on the inner surface of the turbine casing and supporting the turbine vanes, and a ring segment provided on the inner surface of the turbine casing opposite the turbine blades and spaced apart from the turbine blades.

12. The gas turbine according to claim 10, wherein the segment body is formed by additional manufacturing, and the cooling channel is integrally provided inside the segment body while the segment body is being formed by the additional manufacturing.

13. The gas turbine according to claim 10, wherein the first twisted flow path and the second twisted flow path are provided so as to spirally surround the reference line in the same direction from each other.

14. The gas turbine according to any one of claims 10 to 13, wherein the first twisted channel and the second twisted channel are provided to have a circular cross-section.

15. The gas turbine according to claim 14, wherein the first twisted channel and the second twisted channel are provided to have the same diameter as each other.

16. The gas turbine according to claim 15, wherein the diameters of the first twisted flow path and the second twisted flow path are defined as 0.6 mm to 3 mm.

17. The gas turbine according to claim 15, wherein the centers of the first twisted flow path and the second twisted flow path are provided to pass through a reference circle defined around the reference line.

18. The gas turbine according to claim 17, wherein the diameter of the reference circle is defined as 2 mm to 9 mm.

19. The gas turbine according to claim 15, wherein the twist angles of the first twisted flow path and the second twisted flow path with respect to the reference line are defined as 10 degrees to 60 degrees.

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