Thermal deformation self-adaptive adjustment variable geometry turbine

Abstract

The invention provides a thermal deformation self-adaptive adjustment variable geometry turbine, and relates to the technical field of variable geometry turbines for aero-engines and gas turbines.The thermal deformation self-adaptive adjustment variable geometry turbine comprises an inner flow channel casing, an outer flow channel casing and an outer casing which are coaxially arranged from inside to outside in a sleeving mode, and an inner flow channel is limited on the inner side of the inner flow channel casing; an outer flow channel is defined by an annular area between the outer flow channel casing and the outer casing; the turbine blade is arranged between the inner flow channel casing and the outer flow channel casing, the turbine blade is provided with a rotating shaft, the rotating shaft extends in the blade height direction of the turbine blade and is provided with a first end and a second end which are far away from each other, the first end is connected with the outer casing through a spherical hinge structure, and the second end is connected with the interior of the inner flow channel casing through a spherical hinge structure; therefore, the rotating shaft is allowed to generate angle deflection.

Description

Technical Field

[0001] At least one embodiment of this application relates to the field of variable geometry turbine technology for aero engines and gas turbines, and more specifically, to a variable geometry turbine with adaptive thermal deformation adjustment. Background Technology

[0002] Variable geometry turbines are a core technology in the fields of gas turbines and aero engines. Adjusting the installation angle of turbine blades is the mainstream implementation scheme. However, blade jamming caused by thermal deformation is a core design challenge and a key factor restricting its reliability.

[0003] In existing technologies, the cylindrical bushing support structure on both sides of the turbine blades cannot adapt to the problem of axial deformation inconsistency between the inner and outer support positions under hot conditions, resulting in high design iteration and trial-and-error costs. The single-sided support scheme significantly reduces system reliability due to the harsh operating environment of the turbine. In terms of casing design, the traditional single-layer casing is not conducive to temperature control of the support components, which can easily lead to component failure. The assembly, positioning, and fixing technical challenges of the double-layer casing structure that can isolate high-temperature combustion gases currently have no publicly available solutions.

[0004] Therefore, there is an urgent need for a variable geometry turbine to solve problems such as blade jamming, high-temperature failure of support components, and difficulty in assembling and positioning of double-layer casing from the structural design level, so as to improve the structural reliability and operating condition adaptability of the variable geometry turbine. Summary of the Invention

[0005] In view of this, this application proposes a variable geometry turbine with adaptive thermal deformation adjustment, wherein both ends of the turbine blade shaft are connected by a spherical hinge structure to allow the shaft to deflect at an angle, thereby avoiding the technical problem of blade jamming caused by the deformation incoordination of the inner and outer support positions under hot conditions.

[0006] One embodiment of this application provides a variable geometry turbine with adaptive thermal deformation adjustment, including an inner flow channel casing, an outer flow channel casing, and an outer casing coaxially arranged from the inside to the outside. The inner side of the inner flow channel casing defines an inner flow channel, and an annular region between the outer flow channel casing and the outer casing defines an outer flow channel. A turbine blade is disposed between the inner flow channel casing and the outer flow channel casing. The turbine blade is equipped with a rotating shaft, which extends along the blade height direction of the turbine blade and has a first end and a second end that are far apart from each other. The first end is connected to the outer casing, and the second end is connected to the interior of the inner flow channel casing, respectively, through a spherical hinge structure to allow the rotating shaft to deflect at an angle.

[0007] According to an embodiment of this application, the first end is configured to be slidably connected relative to the outer casing, and the second end is configured to form an axial constraint with the inner flow channel casing.

[0008] According to an embodiment of this application, it further includes: a first ball bearing structure, wherein the first end is connected to the outer casing via the first ball bearing structure; and / or, a second ball bearing structure, wherein the second end is connected to the interior of the inner flow channel casing via the second ball bearing structure.

[0009] According to an embodiment of this application, it further includes: a threaded seat disposed in the outer casing; a first fixing nut threadedly engaged with the threaded seat, the first fixing nut having an internal mounting cavity; an adjusting pad disposed in the mounting cavity, and axially pressing the outer ring of the first bearing of the first ball bearing structure together with the first fixing nut; the inner ring of the first ball bearing structure being slidably sleeved on the first end.

[0010] According to an embodiment of this application, the threaded seat has a radially extending shoulder and an axially extending guide on the side facing the outer casing; the shoulder abuts against the outer wall of the outer casing, and the guide passes through the outer casing.

[0011] According to an embodiment of this application, a first sealing structure is provided between the first end and the first fixing nut; and / or, a second sealing structure is provided between the first end and the threaded seat; and / or, a third sealing structure is provided between the first fixing nut and the threaded seat.

[0012] According to an embodiment of this application, it further includes: an inner support disposed in the inner flow channel and connected to the inner flow channel housing; and the second ball bearing structure disposed in the inner support.

[0013] According to an embodiment of this application, the inner support includes a front section and a rear section of the inner support that are axially connected to the variable geometry turbine. The front section of the inner support is provided with a front fixing groove, and the rear section of the inner support is provided with a rear fixing groove. The front fixing groove and the rear fixing groove together form an annular groove. The outer ring of the second bearing of the second ball bearing structure is disposed in the annular groove, and the second end passes through the inner ring of the second bearing of the second ball bearing structure and is fixed axially by a self-locking nut.

[0014] According to an embodiment of this application, it further includes: a fourth sealing structure disposed on the aforementioned inner support and facing the turbine disk to form a toothed sealing structure.

[0015] According to an embodiment of this application, the inner flow channel casing includes a front section and a rear section of the inner flow channel casing that are axially connected along the variable geometry turbine, and the front section and the rear section of the inner flow channel casing are configured to be centered and connected by a stop structure.

[0016] According to an embodiment of this application, it further includes: a retaining ring disposed at the rear section of the inner support and abutting against the inner wall of the rear section of the inner flow channel casing to limit the axial position of the rear section of the inner flow channel casing.

[0017] According to an embodiment of this application, the outer flow channel casing and the outer casing are configured to be radially positioned by a toothed structure; and / or, the outer flow channel casing and the outer casing are bolted together, the outer casing having an oblong hole through which the bolt passes, the oblong hole extending radially along the variable geometry turbine.

[0018] According to the embodiments of this application, a three-layer casing structure coaxially fitted from the inside to the outside precisely defines the independent inner and outer flow channels, creating a suitable aerodynamic flow channel space for the turbine blades. At the same time, both ends of the turbine blade's rotating shaft adopt a spherical hinge structure to connect with the inner casing and the inner flow channel casing, allowing the rotating shaft to freely tilt at an angle. This effectively absorbs the axial and radial deformation differences generated at the inner and outer support positions of the turbine under hot conditions, avoiding blade jamming caused by thermal stress due to deformation incoordination, and improving the working reliability and thermal deformation adaptability of the turbine structure. Attached Figure Description

[0019] The above and other objects, features and advantages of this application will become clearer from the following description of embodiments with reference to the accompanying drawings, in which:

[0020] Figure 1 A cross-sectional view of a variable geometry turbine according to an embodiment of this application is shown;

[0021] Figure 2 A schematic diagram of the assembly of a turbine blade according to an embodiment of this application is shown;

[0022] Figure 3 An exploded view of the inner flow channel casing and inner support of an embodiment of this application is shown;

[0023] Figure 4 A perspective cross-sectional view of a variable geometry turbine located at the turbine blades, according to an embodiment of this application, is shown.

[0024] Figure 5 A perspective view of the outer flow channel casing according to an embodiment of this application is shown;

[0025] Figure 6 An assembly diagram of the front support casing and inner support according to an embodiment of this application is shown.

[0026] In the accompanying drawings, the meanings of the reference numerals are as follows:

[0027] 1. Outer casing; 11. First ball bearing structure; 111. First bearing outer ring; 112. First bearing inner ring; 12. Threaded seat; 121. Shoulder; 122. Guide; 13. First fixing nut; 14. Adjusting shim; 15. First sealing structure; 16. Second sealing structure; 17. Third sealing structure; 2. Outer flow channel casing; 21. Outer flow channel sealing seat; 22. Fifth sealing structure; 23. Outer flow channel end face seal; 24. Outer flow channel bolt; 25. Outer flow channel nut; 26. Flange face boss; 3. Inner flow channel casing; 31. Second ball bearing structure; 311. Second bearing outer ring; 312. Second bearing inner ring; 32. Self-locking nut; 33. Front section of inner flow channel casing; 34. Rear section of inner flow channel casing; 35. Inner flow channel bolt; 36. Inner flow channel nut; 4. Turbine blade; 41. Shaft; 5. Inner support; 51. Front section of inner support; 511. Radial boss; 52. Rear section of inner support; 53. Front fixing groove; 54. Rear fixing groove; 55. Annular groove; 56. Retaining ring; 6. Fourth sealing structure; 7. Front support casing; 71. Radial positioning groove; 72. Inner flow channel end face seal; 73. Fixing hook; 74. Front support casing nut; 75. Front support casing bolt. Detailed Implementation

[0028] The embodiments of this application will now be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of this application. In the following detailed description, numerous specific details are set forth to provide a thorough understanding of the embodiments of this application for ease of explanation. However, it will be apparent that one or more embodiments may be implemented without these specific details. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concepts of this application.

[0029] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of this application. The terms “comprising,” “including,” etc., as used herein indicate the presence of the stated features, steps, operations, and / or mechanisms, but do not exclude the presence or addition of one or more other features, steps, operations, or mechanisms. All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification and should not be interpreted in an idealized or overly rigid manner.

[0030] When using expressions such as "at least one of A, B and C", they should generally be interpreted in accordance with the meaning that is commonly understood by those skilled in the art (e.g., "a system having at least one of A, B and C" should include, but is not limited to, a system having A alone, a system having B alone, a system having C alone, a system having A and B, a system having A and C, a system having B and C, and / or a system having A, B and C, etc.).

[0031] Those skilled in the art will understand that the features described in the various embodiments of this application can be combined and / or combined in various ways, even if such combinations or combinations are not explicitly described in this application. In particular, the features described in the various embodiments of this application can be combined and / or combined in various ways without departing from the spirit and teachings of this application. All such combinations and / or combinations fall within the scope of this application.

[0032] It should be noted that the blade height direction mentioned in this application refers to the extension direction of the turbine blade from the blade root to the blade tip, the axial direction refers to the extension direction of the central axis of the variable geometry turbine, and the radial direction refers to the radial direction of the central axis of the turbine. The above direction definitions are only for the convenience of describing the structural fit relationship and are not intended to limit the actual installation and working direction of the turbine.

[0033] Figure 1 A cross-sectional view of a variable geometry turbine according to an embodiment of this application is shown.

[0034] Embodiments of this application provide a variable geometry turbine with adaptive thermal deformation adjustment, referring to... Figure 1 It includes an inner flow channel casing 3, an outer flow channel casing 2 and an outer casing 1, which are coaxially arranged from the inside to the outside, and a turbine blade 4. The inner side of the inner flow channel casing 3 defines the inner flow channel, and the annular area between the outer flow channel casing 2 and the outer casing 1 defines the outer flow channel. The turbine blade 4 is disposed between the inner flow channel casing 3 and the outer flow channel casing 2. The turbine blade 4 is equipped with a rotating shaft 41, which extends along the blade height direction of the turbine blade 4 and has a first end and a second end that are far apart. The first end is connected to the outer casing 1, and the second end is connected to the interior of the inner flow channel casing 3 by a spherical hinge structure to allow the rotating shaft 41 to deflect at an angle.

[0035] Specifically, the variable geometry turbine achieves adaptive adjustment of thermal deformation through the structural design of a three-layer coaxial casing and the spherical hinge of the turbine blade 4 rotating shaft 41. The inner flow channel casing 3, the outer flow channel casing 2, and the outer casing 1, which are coaxially fitted from the inside to the outside, provide the turbine with an overall flow channel and support foundation. The inner side of the inner flow channel casing 3 forms a closed inner flow channel, and the outer side of the outer flow channel casing 2 and the inner side of the outer casing 1 form an annular outer flow channel. The inner and outer flow channels are independent of each other and together constitute the turbine's aerodynamic flow channel system, providing a suitable channel for the flow of the medium inside the turbine.

[0036] Furthermore, the two ends of the shaft 41 of the turbine blade 4 extend in opposite directions to form a first end and a second end that are far apart. The first end is set towards the outer casing 1, and the second end is set towards the interior of the inner flow channel casing 3. The first end of the shaft 41 is connected to the outer casing 1, and the second end is connected to the interior of the inner flow channel casing 3 through a spherical hinge structure. The spherical hinge structure allows the shaft 41 to freely oscillate around the hinge point within a certain angle range. When the variable geometry turbine is working under hot conditions, and the outer casing 1 and the inner flow channel casing 3 have radial and circumferential deformation differences due to temperature differences, the shaft 41 can adapt to the deformation difference through its own angular oscillation, avoiding problems such as shaft jamming and turbine blade 4 rubbing against the casing caused by deformation incoordination.

[0037] In this implementation, the three-layer coaxial casing structure not only ensures the independence and regularity of the inner and outer flow channels of the turbine, avoiding aerodynamic losses caused by medium mixing, but also ensures the overall circumferential consistency of the turbine through the coaxial design, making the turbine blades 4 more uniformly stressed.

[0038] Furthermore, the spherical hinge structure at both ends of the rotating shaft 41 fundamentally solves the technical problem of inconsistent deformation of the inner and outer support positions under the hot state of the variable geometry turbine. By absorbing the deformation difference through the angular sway of the rotating shaft 41, the generation of thermal stress is avoided, and the working reliability and thermal deformation adaptability of the turbine structure are improved.

[0039] In one illustrative embodiment, the first end of the rotating shaft 41 is configured to be slidably connected relative to the outer casing 1, and the second end of the rotating shaft 41 is configured to form an axial constraint with the inner flow channel casing 3.

[0040] According to the above configuration, the sliding at the first end can effectively absorb the axial deformation difference generated on the inner and outer sides of the turbine under hot conditions, avoiding problems such as shaft jamming and blade rubbing against the casing caused by thermal stress due to uncoordinated axial deformation; the axial constraint at the second end can precisely limit the axial position of the turbine blades, ensuring that the fit clearance between the blades and the inner and outer flow channel casings is constant, avoiding aerodynamic losses caused by uneven flow channel clearance due to blade axial movement, and providing a stable inner positioning basis for turbine blade angle adjustment.

[0041] Figure 2 A schematic diagram of the assembly of a turbine blade according to an embodiment of this application is shown.

[0042] In one illustrative embodiment, reference is made to... Figure 2 It also includes a first ball bearing structure 11, the first end of which is connected to the outer casing 1; and / or a second ball bearing structure 31, the second end of which is connected to the interior of the inner flow channel casing 3.

[0043] In this implementation, the first ball bearing structure 11 and the second ball bearing structure 31 are used as the spherical hinge carrier between the rotating shaft 41 and the casing. Through the spherical fit characteristics of the ball bearing, the rotating shaft 41 is allowed to freely swing at an angle. This can effectively absorb the radial and circumferential deformation differences generated by the inner and outer support positions of the turbine under hot conditions, and avoid the problems of rotating shaft jamming and blade rubbing caused by deformation incoordination.

[0044] In one illustrative embodiment, reference is made to... Figure 2 It also includes a threaded seat 12, a first fixing nut 13, and an adjusting washer 14. The threaded seat 12 is disposed on the outer casing 1; the first fixing nut 13 is threadedly engaged with the threaded seat 12, and the first fixing nut 13 has an internal mounting cavity; the adjusting washer 14 is disposed in the mounting cavity, and together with the first fixing nut 13, it axially presses the outer ring 111 of the first ball bearing structure 11; the inner ring 112 of the first ball bearing structure 11 is slidably sleeved on the first end.

[0045] Specifically, the first ball bearing structure 11 is installed and fixed through the coordinated cooperation of the threaded seat 12, the first fixing nut 13 and the adjusting pad 14. The adjusting pad 14 and the first fixing nut 13 axially press the outer ring 111 of the first bearing, which can ensure the structural stability of the connection between the first ball bearing structure 11 and the outer casing 1 and prevent the bearing from loosening under the high temperature and high vibration of the turbine. The sliding sleeve cooperation between the inner ring 112 of the first bearing and the first end of the rotating shaft 41 can retain the sliding freedom of the rotating shaft 41 along the axial direction and adapt to the absorption requirements of thermal axial deformation.

[0046] Furthermore, the threaded engagement between the threaded seat 12 and the first fixing nut 13 makes the disassembly, assembly, and maintenance of the first ball bearing structure 11 more convenient.

[0047] In some embodiments, each turbine blade 4 on the outer casing 1 is independently provided with a threaded seat 12. Multiple threaded seats 12 are evenly arranged along the circumference of the outer casing 1 and are adapted to each turbine blade 4. Each threaded seat 12 provides a dedicated mounting and fixing base for the first ball bearing structure 11 of the corresponding turbine blade 4.

[0048] In some embodiments, the adjusting pad 14 can be selected with different thicknesses according to the processing and assembly errors, effectively compensating for dimensional deviations, ensuring the coaxiality and tightness of the first ball bearing structure 11 during installation, avoiding failure caused by uneven force on the first ball bearing structure 11, and taking into account both the sliding adaptability of the rotating shaft 41 and the installation stability of the first ball bearing structure 11.

[0049] In one illustrative embodiment, reference is made to... Figure 2The threaded seat 12 has a radially extending shoulder 121 and an axially extending guide 122 on the side facing the outer casing 1; the shoulder 121 abuts against the outer wall of the outer casing 1, and the guide 122 passes through the outer casing 1.

[0050] Specifically, the threaded seat 12 has an integrally formed shoulder 121 extending radially and a guide portion 122 extending axially on the side facing the outer casing 1. The shoulder 121 abuts tightly against the outer wall of the outer casing 1 during the assembly of the threaded seat 12, forming an axial limit and radial initial positioning of the threaded seat 12. The guide portion 122 is coaxially inserted into a pre-set mounting through hole in the outer casing 1, providing precise axial guidance for the assembly of the threaded seat 12, enabling the threaded seat 12 to be quickly and accurately installed to the preset position. At the same time, the cooperation between the guide portion 122 and the mounting through hole further restricts the circumferential rotation of the threaded seat 12.

[0051] According to the above configuration, the shoulder 121 and guide 122 can be configured so that the assembly and positioning of the threaded seat 12 does not require additional auxiliary tooling, thus improving assembly efficiency. At the same time, the dual positioning and limiting structure ensures the connection stability between the threaded seat 12 and the outer casing 1, preventing the threaded seat 12 from radially shifting or circumferentially loosening during turbine operation, and providing a solid foundation for the cooperation between the first ball bearing structure 11 and the rotating shaft 41.

[0052] In one illustrative embodiment, reference is made to... Figure 2 A first sealing structure 15 is provided between the first end of the rotating shaft 41 and the first fixing nut 13; and / or, a second sealing structure 16 is provided between the first end of the rotating shaft 41 and the threaded seat 12; and / or, a third sealing structure 17 is provided between the first fixing nut 13 and the threaded seat 12. The three sealing structures are arranged sequentially along the medium leakage path to form a multi-layer sealing barrier.

[0053] In some implementations, the first sealing structure 15 and the second sealing structure 16 are sealed with high-temperature resistant elastic expansion rings, which are adapted to the axial sliding and angular wobble of the rotating shaft 41, without sealing interference;

[0054] In some embodiments, the third sealing structure 17 employs a metal surface seal or a sealing ring seal to achieve a static seal between the fixed components.

[0055] Based on the above configuration, the multi-seal design combining dynamic and static seals blocks the leakage of medium in the turbine aerodynamic flow channel from the gap between the rotating shaft 41 and the outer support component, significantly reducing end-area leakage loss and improving the turbine's aerodynamic efficiency. At the same time, all sealing structures are adapted to the turbine's high-temperature working environment and the motion characteristics of the rotating shaft 41, achieving sealing without affecting the thermal deformation adaptation of the rotating shaft 41.

[0056] In one illustrative embodiment, reference is made to... Figure 1 and Figure 2 It also includes an inner support 5, which is located in the inner flow channel and connected to the inner flow channel casing 3; the second ball bearing structure 31 is located in the inner support 5.

[0057] In detail, an inner support 5 is fixedly installed in the inner flow channel of the inner flow channel casing 3. The inner support 5 is rigidly connected to the inner flow channel casing 3. The second ball bearing structure 31 is directly integrated on the inner support 5. The inner support 5 becomes the core support carrier of the second end of the rotating shaft 41, and transmits the supporting force of the rotating shaft 41 to the inner flow channel casing 3.

[0058] In this implementation, by setting an inner support 5 rigidly connected to the inner flow channel casing 3 in the inner flow channel, and integrating the second ball bearing structure 31 onto the inner support 5, the inner support 5 becomes the core support carrier for the second end of the rotating shaft 41. This achieves stable transmission of the bearing structure support force to the casing, providing reliable inner hinge support for the rotating shaft 41, and also avoids direct contact between the second ball bearing structure 31 and the high-temperature inner flow channel casing 3, effectively reducing the bearing's operating temperature, minimizing the adverse effects of high temperature on the bearing structure performance, and improving the bearing's working stability and service life. Furthermore, the setting of the inner support 5 separates the bearing installation area from the inner flow channel casing flow channel surface, without damaging the regular shape of the inner flow channel, avoiding aerodynamic losses caused by protrusions or gaps on the flow channel surface due to bearing installation, thus balancing high-temperature protection of the bearing structure, support reliability, and turbine aerodynamic efficiency.

[0059] Figure 3 An exploded view of the inner flow channel casing and inner support of an embodiment of this application is shown.

[0060] In one illustrative embodiment, reference is made to... Figure 3 The inner support 5 includes a front section 51 and a rear section 52 that are axially connected to the variable geometry turbine. The front section 51 is provided with a front fixing groove 53, and the rear section 52 is provided with a rear fixing groove 54. The front fixing groove 53 and the rear fixing groove 54 together form an annular groove 55. The outer ring 311 of the second bearing of the second ball bearing structure 31 is disposed in the annular groove 55, and the second end passes through the inner ring 312 of the second bearing of the second ball bearing structure 31, and is fixed axially by a self-locking nut 32. This makes the second end of the rotating shaft 41 rigidly connected to the inner ring 312 of the second bearing, realizing the axial constraint and spherical hinge fit of the second end of the rotating shaft 41.

[0061] In this implementation, the split design of the inner support 5 eliminates the need for axial insertion when assembling the second ball bearing structure 31, greatly reducing the assembly difficulty; the annular groove 55 formed by the front fixing groove 53 and the rear fixing groove 54 fully wraps and fixes the outer ring 311 of the second bearing of the second ball bearing structure 31, ensuring the coaxiality and stability of the installation.

[0062] Furthermore, after the second end of the rotating shaft 41 passes through the inner ring 312 of the second bearing, it is axially locked by the self-locking nut 32, so that the rotating shaft 41 and the inner ring 312 of the second bearing form a rigid connection. This accurately realizes the axial constraint and spherical hinge fit of the second end of the rotating shaft 41, which not only ensures the axial position accuracy of the turbine blade 4, but also adapts to the radial and circumferential deformation differences under hot conditions through the spherical hinge.

[0063] In some embodiments, the front section 51 of the inner support is provided with a plurality of front fixing grooves 53 and the rear section 52 of the inner support is provided with a plurality of rear fixing grooves 54, which are evenly arranged along the circumference of the inner support 5 and are adapted to the turbine blades 4 one by one. The annular groove 55 formed by each front fixing groove 53 and the rear fixing groove 54 provides a dedicated installation and fixing foundation for the second ball bearing structure 31 of the corresponding turbine blade 4.

[0064] In one illustrative embodiment, reference is made to... Figure 1 and Figure 2 It also includes a fourth sealing structure 6, which is located in the inner support 5 and faces the turbine disk to form a toothed sealing structure.

[0065] The fourth sealing structure 6 cooperates with the grate boss of the turbine disk to form a grate seal structure. This grate seal structure reduces the pressure of the medium leaking towards the turbine disk side along the inner flow channel through a multi-stage throttling effect, significantly reducing the flow velocity and flow rate of the leaking medium. At the same time, the grate sealing ring and the turbine disk have a non-contact fit, with no frictional wear.

[0066] In this implementation, the grating seal formed by the fourth sealing structure 6 specifically solves the leakage problem in the end area of ​​the inner flow channel, effectively reduces the leakage loss of the inner flow channel medium, and improves the working efficiency of the turbine; the non-contact mating method makes the sealing structure wear-free, greatly improving the service life of the sealing structure, while avoiding vibration and noise caused by contact friction.

[0067] In one illustrative embodiment, reference is made to... Figure 3 The inner flow channel casing 3 includes an inner flow channel casing front section 33 and an inner flow channel casing rear section 34 that are axially joined along the variable geometry turbine. The inner flow channel casing front section 33 and inner flow channel casing rear section 34 are configured to be centered connected by a stop structure.

[0068] In some embodiments, the stop structure is a stepped structure with a convex-concave fit, and the mating surfaces of the convex stop and the concave stop are high-precision cylindrical surfaces to achieve coaxiality centering after the two are connected. After centering, axial fixation is achieved by fasteners evenly arranged in the circumference.

[0069] In this implementation, the split design of the inner flow channel casing 3 facilitates the processing and manufacturing of the inner flow channel casing 3 and the precision machining of the flow channel profile, solving the problems of high difficulty and low precision in machining the deep cavity of the integral inner flow channel casing 3; the centering connection method of the stop structure ensures the coaxiality and circumferential consistency of the inner flow channel casing front section 33 and inner flow channel casing rear section 34 after docking, making the inner flow channel profile continuous and regular, and avoiding aerodynamic losses caused by flow channel steps or sway.

[0070] In one illustrative embodiment, reference is made to... Figure 2 and Figure 3 It also includes a retaining ring 56, which is disposed in the rear section 52 of the inner support and abuts against the inner wall of the rear section 34 of the inner flow channel casing to limit the axial position of the rear section 34 of the inner flow channel casing.

[0071] In some embodiments, refer to Figure 3 The front section 33 and the rear section 34 of the inner flow channel casing are fixedly connected by inner flow channel bolts 35 and inner flow channel nuts 36.

[0072] In some embodiments, the retaining ring 56 is an annular boss structure that extends radially outward along the rear section 52 of the inner support. The end face of the retaining ring 56 axially abuts against the inner wall of the rear section 34 of the inner flow channel casing, thereby axially limiting the rear section 34 of the inner flow channel casing. The circumferential fit between the retaining ring 56 and the inner wall of the rear section 34 of the inner flow channel casing is clearance fit, which does not restrict the thermal expansion and deformation of the rear section 34 of the inner flow channel casing.

[0073] In this implementation, the retaining ring 56 enables precise axial positioning of the rear section 34 of the inner flow channel casing, preventing axial movement of the inner flow channel casing 3 due to medium impact or vibration during turbine operation, and ensuring a constant fit clearance between the inner flow channel casing 3 and the turbine blades 4; at the same time, the clearance fit design allows the rear section 34 of the inner flow channel casing to expand freely in the radial direction, avoiding thermal stress caused by obstructed thermal expansion that could lead to casing deformation or cracking.

[0074] In one illustrative embodiment, the outer flow channel casing 2 and the outer casing 1 are configured to be radially positioned by a toothed structure; and / or, the outer flow channel casing 2 and the outer casing 1 are bolted together, the outer casing 1 having a waist-shaped hole through which the bolt passes, the waist-shaped hole extending radially along the variable geometry turbine.

[0075] In detail, the toothed structure includes protruding teeth evenly arranged circumferentially along the inner side of the outer casing 1 and grooves evenly arranged circumferentially along the outer side of the outer flow channel casing 2. The protruding teeth and grooves are fitted together with a gap to achieve coaxiality centering.

[0076] The outer flow channel casing 2 and the outer casing 1 are also axially clamped together by bolts evenly arranged in the circumference. The outer casing 1 has a waist-shaped hole to accommodate the bolts. The waist-shaped hole extends radially along the variable geometry turbine. The bolts and the waist-shaped hole are clearance fit.

[0077] In this implementation, the radial positioning of the toothed structure makes the coaxiality accuracy of the outer flow channel casing 2 and the outer casing 1 higher, ensuring the uniformity of the annular gap of the outer flow channel and avoiding the yaw of the medium flow and aerodynamic losses caused by uneven flow channel gap; the radially extended waist-shaped hole provides sufficient displacement space for the radial thermal expansion of the outer flow channel casing 2, allowing the outer flow channel casing 2 to deform freely in the radial direction with temperature changes, avoiding thermal stress between it and the outer casing 1, while the axial compression connection of the bolts can still ensure the overall stability of the connection between the two.

[0078] Figure 4 A perspective cross-sectional view of a variable geometry turbine located at the turbine blades, according to an embodiment of this application, is shown. Figure 5 A perspective view of the outer flow channel casing according to an embodiment of this application is shown.

[0079] In one illustrative embodiment, reference is made to... Figure 2 , Figure 4 and Figure 5 The outer flow channel casing 2 is equipped with an outer flow channel sealing seat 21, a fifth sealing structure 22, and an outer flow channel end face seal 23. It is fastened to the outer casing 1 by the outer flow channel bolts 24 and the outer flow channel nuts 25, forming an outer double-layer casing structure that combines sealing performance and assembly stability.

[0080] In some embodiments, a fifth sealing structure 22 is independently provided on the outer flow channel casing 2 for each turbine blade 4. An elastic expansion ring seal is adapted to be installed at the corresponding position of the turbine blade 4. The fifth sealing structure 22 formed by the elastic expansion ring seal cooperates with the outer flow channel sealing seat 21 to effectively block the leakage of gas between the outer casing 1 and the outer flow channel casing 2 into the turbine pneumatic flow channel, avoid the leakage gas from disturbing the normal flow of the medium in the flow channel, and prevent the aerodynamic efficiency from decreasing.

[0081] The outer flow channel casing 2 has an integrally formed flange boss 26. The flange boss 26 provides a dedicated axial space for the installation of the outer flow channel end face seal 23 of the outer flow channel casing 2. After the outer flow channel bolts 24 are tightened, the end face of the outer flow channel casing 2 and the flange boss 26 are precisely fitted together, so that an installation gap that matches the outer flow channel end face seal 23 is formed between them. Moreover, the height of the flange boss 26 is completely matched with the axial dimension of the outer flow channel end face seal 23 after compression in the working state, which can ensure that the outer flow channel end face seal 23 is uniformly compressed, realize the static seal of the mating surface of the outer casing 1 and the outer flow channel casing 2, and block the gas leakage path of the gap between the two ends.

[0082] In this implementation, the outer flow channel casing 2 is equipped with an independent radial sealing structure for each turbine blade 4, which, together with the end face seal, forms a full-dimensional sealing system, significantly improving the sealing performance of the outer double-layer casing and avoiding aerodynamic losses caused by leakage. The circumferentially evenly arranged multi-position toothed grooves ensure the coaxiality and assembly accuracy of the outer flow channel casing 2 and the outer casing 1, providing a regular flow path for the medium flow. The outer flow channel nut 25 achieves anti-loosening tightening, and the height of the flange boss 26 is precisely matched with the compression size of the seal, which not only reserves the sealing installation space but also ensures the optimal working state of the seal, preventing seal failure caused by overpressure damage or insufficient compression.

[0083] In some embodiments, refer to Figure 1 The variable geometry turbine also includes a front support casing 7. The outer casing 1 is positioned and assembled on the front support casing 7 through a stop structure, forming the basic support frame of the turbine as a whole. The front support casing 7 provides a stable installation reference for core components such as the outer casing 1 and the inner flow channel casing 3, ensuring the coaxiality and positional accuracy of each component after assembly.

[0084] In some embodiments, refer to Figure 2 The front support casing 7 is provided with a radial positioning groove 71, the front section 33 of the inner flow channel casing 3 is provided with a radial groove 331, and the front section 51 of the inner support is provided with a radial boss 511. The radial positioning groove 71, the radial groove 331 and the radial boss 511 form a toothed groove mating structure, so as to realize the radial centering and angular positioning of the inner flow channel casing 3 and the inner support 5 relative to the front support casing 7, further strengthening the assembly consistency of the inner and outer parts, and avoiding positional displacement caused by vibration or thermal deformation during operation.

[0085] In some embodiments, refer to Figure 2 An inner flow channel end face seal 72 is provided at the contact surface between the inner support 5 and the front support casing 7. The inner flow channel end face seal 72 adopts a high temperature resistant sealing ring to achieve static sealing between the inner support 5 and the front support casing 7, blocking the leakage of the inner flow medium from the gap between the two. Together with the fourth sealing structure 6, it further improves the overall sealing performance of the turbine and reduces leakage loss.

[0086] Figure 6 An assembly diagram of the front support casing and inner support according to an embodiment of this application is shown.

[0087] In some embodiments, refer to Figure 1 and Figure 6The front support housing 7 is equipped with a fixing hook 73, and a front support housing nut 74 is fitted onto the fixing hook 73. A front support housing bolt 75 passes sequentially through the inner support front section 51 and inner support rear section 52 of the inner support 5 and connects to the front support housing nut 74. This secures the inner flow channel housing 3 and the inner support 5 to the front support housing 7 via the engagement of the front support housing bolt 75 and the front support housing nut 74, achieving axial fixation of the inner flow channel housing 3 and the inner support 5 relative to the front support housing 7. This prevents component movement caused by axial deformation under heat and improves the overall structural connection stability. The inner flow channel housing front section 33 is clamped between the front support housing 7 and the inner support front section 51 for fixation.

[0088] In some embodiments, the outer flow channel nut 25, the inner flow channel nut 36, and the front support casing nut 74 are all self-locking flared nuts.

[0089] The embodiments of this application have been described above. However, these embodiments are merely illustrative and not intended to limit the scope of this application. Although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination. Without departing from the scope of this application, those skilled in the art can make various substitutions and modifications, all of which should fall within the scope of this application.

Claims

1. A variable geometry turbine with adaptive thermal deformation adjustment, characterized in that, include: An inner flow channel casing, an outer flow channel casing, and an outer casing are coaxially fitted from the inside to the outside. The inner side of the inner flow channel casing defines the inner flow channel, and the annular area between the outer flow channel casing and the outer casing defines the outer flow channel. A turbine blade is disposed between the inner flow channel casing and the outer flow channel casing. The turbine blade is equipped with a rotating shaft that extends along the blade height direction and has a first end and a second end that are far apart from each other. The first end is connected to the outer casing, and the second end is connected to the interior of the inner flow channel casing by a spherical hinge structure to allow the rotating shaft to oscillate at an angle.

2. The variable geometry turbine according to claim 1, characterized in that, The first end is configured to be slidably connected relative to the outer casing, and the second end is configured to form an axial constraint with the inner flow channel casing.

3. The variable geometry turbine according to claim 2, characterized in that, Also includes: A first ball bearing structure, wherein the first end is connected to the outer casing via the first ball bearing structure; And / or, a second ball bearing structure, wherein the second end is connected to the interior of the inner flow channel casing via the second ball bearing structure.

4. The variable geometry turbine according to claim 3, characterized in that, Also includes: A threaded seat is provided on the outer casing; A first fixing nut is threadedly engaged with the threaded seat, and the first fixing nut has an internal mounting cavity. An adjusting pad is provided in the mounting cavity and, together with the first fixing nut, axially presses the outer ring of the first bearing of the first ball bearing structure. The inner ring of the first bearing in the first ball bearing structure is slidably sleeved on the first end.

5. The variable geometry turbine according to claim 4, characterized in that, The threaded seat has a radially extending shoulder and an axially extending guide on the side facing the outer casing. The shoulder abuts against the outer wall of the outer casing, and the guide portion passes through the outer casing.

6. The variable geometry turbine according to claim 4, characterized in that, A first sealing structure is provided between the first end and the first fixing nut; And / or, a second sealing structure is provided between the first end and the threaded seat; And / or, a third sealing structure is provided between the first fixing nut and the threaded seat.

7. The variable geometry turbine according to claim 3, characterized in that, Also includes: An inner support is disposed in the inner flow channel and connected to the inner flow channel casing; The second ball bearing structure is disposed on the inner support.

8. The variable geometry turbine according to claim 7, characterized in that, The inner support includes a front section and a rear section of the inner support that are axially connected to the variable geometry turbine. The inner support has a front fixing groove at the front and a rear fixing groove at the rear. The front fixing groove and the rear fixing groove together form an annular groove. The outer ring of the second bearing of the second ball bearing structure is disposed in the annular groove. The second end passes through the inner ring of the second bearing of the second ball bearing structure and is fixed axially by a self-locking nut.

9. The variable geometry turbine according to claim 7 or 8, characterized in that, Also includes: A fourth sealing structure is provided on the inner support and facing the turbine disk to form a comb-tooth sealing structure.

10. The variable geometry turbine according to claim 8, characterized in that, The inner flow channel casing includes a front section and a rear section of the inner flow channel casing that are axially joined along the variable geometry turbine, and the front and rear sections of the inner flow channel casing are configured to be centered and connected by a stop structure.

11. The variable geometry turbine according to claim 10, characterized in that, Also includes: A retaining ring is disposed at the rear section of the inner support and abuts against the inner wall of the rear section of the inner flow channel casing to restrict the axial position of the rear section of the inner flow channel casing.

12. The variable geometry turbine according to claim 1, characterized in that, The outer flow channel casing and the outer casing are configured to be radially positioned by a toothed structure; And / or, the outer flow channel casing is bolted to the outer casing, the outer casing having a waist-shaped hole through which the bolt passes, the waist-shaped hole extending radially along the variable geometry turbine.

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