Double-side bag-type rim sealing structure for movable and static wheel disc surfaces, turbine and gas turbine

Abstract

The double-side bag type rim sealing structure comprises a static disc and a movable disc, a disc cavity area is formed between the static disc and the movable disc, a static disc side bag type structure is arranged on the side face of the static disc, and a movable disc side bag type structure is arranged on the side face of the movable disc. The sealing cold air is mixed with the gas through the disc cavity area, the requirement for the sealing cold air can be reduced through the structure, the gas is effectively prevented from invading the disc cavity through the rim gap while the mainstream pneumatic performance of the gas turbine is not affected, and the good sealing effect is achieved with the small amount of the sealing cold air.

Description

Technical Field

[0001] The invention belongs to the technical field of turbine machinery, and relates to a double-sided bag-type wheel rim sealing structure for a moving and stationary wheel disc surface, a turbine and a gas turbine. Background Art

[0002] As a kind of heavy mechanical equipment, gas turbines are widely used in gas power generation, aviation propulsion, ship power and other fields. They play an irreplaceable and important role in promoting high-quality economic development, ensuring energy security, orderly promoting "carbon peak and carbon neutrality" and assisting national defense and security construction in my country.

[0003] In order to improve the output power and efficiency of gas turbines, increasing the inlet temperature of gas turbines is an effective method. At present, the inlet temperature of the world's top gas turbines has reached 2000℃. When the mainstream high-temperature gas of the gas turbine flows inside the blade channel, it will directly contact the surface of the blades and the end wall of the channel, causing fatigue, creep and even thermal failure of the metal material. The high-temperature gas will also invade the turbine disc cavity through the rotor-static gap. The invading gas will contact the wall of the wheel disc, increase the thermal stress and heat load of the wheel disc, further affect the working stability and life of the turbine disc and rotor, and greatly reduce the life of the hot end components of the turbine, especially the rotating components. To solve this problem, a sealing structure is usually designed at the rim of the rotor-static disc cavity to prevent the mainstream gas from directly invading the wheel disc through the rotor-static gap at the rim, and introduce the cold air from the compressor into the disc cavity to isolate the high-temperature gas, protect and cool the wall of the wheel disc, and the cold air will also be injected into the mainstream channel through the rim gap to further suppress the invasion of gas.

[0004] As an important component of the secondary air system, the rim seal plays an important role in protecting the hot end components and improving the efficiency of the gas turbine. At present, in order to suppress the intrusion of gas into the rotor-stator disc cavity as efficiently as possible, the mainstream solution is to increase the amount of sealing cold air and optimize the rim seal structure. The increase in the amount of sealing cold air can increase the overall pressure in the disc cavity, and improve the cooling effect on the disc wall of the disc cavity while significantly reducing the intrusion of gas. However, the increase in the amount of cold air will reduce the aerodynamic performance of the mainstream blade grid, which will lead to a decrease in the overall efficiency of the gas turbine. Starting from the rim seal structure, the demand for sealing cold air can be effectively reduced, and a higher sealing efficiency can be achieved with less sealing cold air. Therefore, improving and designing a rim seal structure with high sealing performance has very significant engineering significance and application value for improving the rim sealing performance and the overall efficiency of the turbine. Summary of the invention

[0005] The object of the present invention is to overcome the shortcomings of the above-mentioned prior art and to provide a double-sided bag-type rim sealing structure for the moving and stationary wheel discs, a turbine and a gas turbine. This structure can reduce the demand for sealing cold air, and while not affecting the mainstream aerodynamic performance of the gas turbine, it can effectively inhibit the gas from invading the disc cavity through the rim gap, thereby achieving a better sealing effect with a smaller amount of sealing cold air.

[0006] In order to achieve the above-mentioned purpose, the present invention discloses a double-sided bag-type wheel rim sealing structure for dynamic and static wheel discs, including a static disc and a dynamic disc, a disc cavity area is formed between the static disc and the dynamic disc, a static disc side bag-type structure is arranged on the side of the static disc, and a dynamic disc side bag-type structure is arranged on the side of the dynamic disc. During operation, the sealed cold air is mixed with the fuel gas through the disc cavity area.

[0007] The further improvement of the double-sided bag-type wheel rim sealing structure of the dynamic and static wheel disc surface of the present invention is:

[0008] Furthermore, the side pocket structure of the stator disc is located on the wall surface of the stator disc near the wheel rim gap in the disc cavity area;

[0009] Furthermore, the side pocket structure of the moving plate is located on the wall surface of the moving plate within the wheel rim gap.

[0010] Furthermore, the bag-type structures on the side of the stationary disk and the bag-type structures on the side of the moving disk extend in the circumferential direction, perpendicular to or approximately perpendicular to the radial and axial directions of the turbine.

[0011] Furthermore, each of the side pocket structures of the static disk has a different circumferential angle θ3 and a different circumferential position angle θ4.

[0012] Furthermore, each moving plate side pocket structure has a different circumferential angle θ5 and a different circumferential position angle θ7.

[0013] Furthermore, the bag-type structure on the stationary disk side and the bag-type structure on the moving disk side have the same bag-type geometry type.

[0014] Furthermore, the bag-type structure on the stationary disk side and the bag-type structure on the moving disk side have arbitrary bag-type geometric parameters.

[0015] The invention discloses a turbine, comprising a double-sided bag-type wheel rim sealing structure on a moving and stationary wheel disc surface.

[0016] The invention discloses a gas turbine, comprising a turbine.

[0017] The present invention has the following beneficial effects:

[0018] During specific operation of the double-sided bag-type rim sealing structure of the moving and static disc surfaces, the turbine and the gas turbine described in the present invention, a stator disc side bag-type structure is provided on the side of the stator disc, and a moving disc side bag-type structure is provided on the side of the moving disc. The existence of the double-sided bag-type structures of the moving and static disc surfaces can greatly extend the flow path of the invading gas. When the mainstream gas invades the disc cavity through the rim gap, the invading gas will first enter the bag-type structures on the stator disc surface side and the moving disc surface side, and violently mix with the sealed cold air flowing outward to form multiple vortex structures, and gradually dissipate the momentum of the radially inward invasion of the gas. At the circumferential position where the bag-type structure is not provided, the sealed cold air will quickly pass through the sealing structure to impact the high-temperature gas at the rim gap, and the cold air and the gas will be violently mixed to prevent the gas from invading the disc cavity, thereby achieving a better sealing effect with a smaller amount of sealed cold air. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0020] Figure 1 This is a meridian plane diagram of the main flow blade channel and rim sealing structure of the gas turbine.

[0021] Figure 2 It is a two-dimensional schematic diagram of the wheel rim sealing structure designed according to the present invention.

[0022] Figure 3 It is a two-dimensional schematic diagram of the meridian plane and circumferential direction of the static disk surface in the design structure of the present invention.

[0023] Figure 4 It is a two-dimensional schematic diagram of the meridian plane and circumferential direction of the moving disk side in the design structure of the present invention.

[0024] Figure 5 It is a three-dimensional schematic diagram of the wheel rim sealing structure designed according to the present invention.

[0025] Figure 6 It is a three-dimensional schematic diagram of the moving disc 6 and the moving blade channel according to an embodiment of the present invention.

[0026] Figure 7 It is a three-dimensional schematic diagram of a single-stage turbine blade grid using an embodiment of the present invention.

[0027] Among them, 1 is the stationary blade grid, 2 is the moving blade grid, 3 is the casing, 4 is the disc cavity area, 5 is the stationary disc, 6 is the moving disc, 7 is the stationary disc side pocket structure, and 8 is the moving disc side pocket structure. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] In the description of the present invention, it should be understood that the terms “include” and “comprises” indicate the presence of described features, wholes, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or collections thereof.

[0030] It should also be understood that the terms used in the present specification are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the present specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0031] It should be further understood that the term "and / or" used in the present specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes these combinations. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in the present invention generally indicates that the associated objects are in an "or" relationship.

[0032] It should be understood that, although the terms first, second, third, etc. may be used to describe preset ranges, etc. in the embodiments of the present invention, these preset ranges should not be limited to these terms. These terms are only used to distinguish preset ranges from each other. For example, without departing from the scope of the embodiments of the present invention, the first preset range may also be referred to as the second preset range, and similarly, the second preset range may also be referred to as the first preset range.

[0033] The word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrases "if it is determined" or "if (stated condition or event) is detected" may be interpreted as "when it is determined" or "in response to determining" or "when detecting (stated condition or event)" or "in response to detecting (stated condition or event)", depending on the context.

[0034] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. The components of the embodiments of the present invention described and shown in the drawings here can usually be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0035] Various structural schematic diagrams of the embodiments disclosed in the present invention are shown in the accompanying drawings. These figures are not drawn to scale, and some details are magnified and some details may be omitted for the purpose of clear expression. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships therebetween are only exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations, and those skilled in the art may additionally design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0036] Embodiment 1

[0037] In view of the low sealing efficiency of the existing gas turbine rim sealing structure, the large demand for sealing cold air, and the resulting reduction in the aerodynamic performance of the mainstream blade grid, the present invention proposes a double-sided bag-type rim sealing structure on the dynamic and static wheel disc surfaces, which can effectively improve the rim sealing performance and optimize the internal flow characteristics, thereby achieving a better sealing level with a smaller amount of sealing cold air.

[0038] The present invention takes the first-stage blade cascade model of a certain type of gas turbine as an example to explain the designed rim seal structure in detail. The meridian plane schematic diagram of the main flow blade cascade channel and the rim seal structure of the gas turbine is shown in the attached figure. Figure 1 ; The two-dimensional schematic diagram of the wheel rim sealing structure designed according to the present invention is shown in the attached Figure 2 ; The two-dimensional schematic diagram of the meridian plane and circumferential direction of the static disk surface in the design structure of the present invention is shown in the attached Figure 3 ; The two-dimensional schematic diagram of the meridian plane and circumferential direction of the moving disk surface in the design structure of the present invention is shown in the attached Figure 4 ; The three-dimensional schematic diagram of the wheel rim sealing structure designed according to the present invention is shown in the attached Figure 5 ; The three-dimensional schematic diagram of the moving disk 6 and the moving blade passage according to the embodiment of the present invention is shown in the attached Figure 6 ; A three-dimensional schematic diagram of a single-stage turbine blade cascade using an embodiment of the present invention is shown in the attached Figure 7 .

[0039] refer to Figure 1The first stage of a certain type of gas turbine is composed of 48 stationary blade cascades 1 and 96 moving blade cascades 2. The high-temperature mainstream gas flows in from the left inlet of the stationary blade cascade 1 and flows out from the right outlet of the moving blade cascade 2. The casing 3 is above the channel. The stationary blade cascade 1 in the channel is installed on the stator, and the moving blade cascade 2 is installed on the high-speed rotating mover. A rim gap is formed between the rotor and the stator. Affected by the non-uniform distribution of circumferential pressure and the rotation effect of the moving disk 6, the mainstream high-temperature gas will invade the disc cavity area 4 through the gap when flowing through the rim gap. The disc cavity area 4 is formed between the stationary disk 5 and the moving disk 6. The intruding gas contacts the wall of the stationary disk 5 and the moving disk 6, increasing the thermal stress and heat load of the wheel disk, affecting the working stability of the turbine rotor and rotor, and greatly reducing the life of the turbine rotor and stator. The rim sealing structure is arranged at the edge of the disc cavity area 4 to prevent the high-temperature combustion gas from directly invading the disc cavity area 4 through the gap, and some cold air is extracted from the compressor and led to the bottom inlet of the disc cavity area 4 to be injected into the mainstream through the rim gap, thereby cooling and protecting the disc wall surface and preventing the high-temperature combustion gas from invading inward.

[0040] Based on the above analysis, the present invention discloses a double-sided bag-type wheel rim sealing structure for the moving and stationary wheel discs, including a stationary disc side bag-type structure 7 arranged on the side of the stationary disc 5 and a moving disc side bag-type structure 8 arranged on the side of the moving disc 6. The stationary disc side bag-type structure 7 is located on the wall surface of the stationary disc 5 near the wheel rim gap in the disc cavity area 4; the moving disc side bag-type structure 8 is located on the wall surface of the moving disc 6 in the wheel rim gap.

[0041] As an embodiment of the present invention, reference Figure 2 The depth S1 of the pocket structure 7 on the static disk side is 15 mm, the depth S2 of the pocket structure 8 on the dynamic disk side is 22.8 mm, and the inclination angle θ1 is 30°.

[0042] As an embodiment of the present invention, the bag-type structure 7 on the stationary disk side and the bag-type structure 8 on the moving disk side extend in the circumferential direction, perpendicular to or approximately perpendicular to the radial and axial directions of the turbine.

[0043] As an embodiment of the present invention, the pitch angle θ2 of the turbine blade channel model is 7.5°, and its rim sealing structure includes a stationary disc side bag structure 7 and two moving disc side bag structures 8. The circumferential angle θ3 of the stationary disc side bag structure 7 is 3.5°, and the circumferential position angle θ4 of the stationary disc side bag structure 7 is 2.46°. The circumferential angle θ5 of the moving disc side bag structure 8 is 3.5°, the circumferential span θ6 of the two moving disc side bag structures 8 is 3.75°, and the circumferential position angle θ7 of the right moving disc side bag structure 8 is 0.45°, refer to Figure 3 and Figure 4 .

[0044] As an embodiment of the present invention, the static disk side pocket-type structure 7 can have different circumferential angles θ3 and different circumferential position angles θ4; the pocket-type structures 8 on the moving disk side can have different circumferential angles θ5 and different circumferential position angles θ7; the pocket-type structures 7 on the static disk side and the pocket-type structures 8 on the moving disk side have the same bag-type geometry type; the pocket-type structures 7 on the static disk side and the pocket-type structures 8 on the moving disk side have arbitrary bag-type geometry parameters.

[0045] As an embodiment of the present invention, the circumferential pitch angle of the turbine blade channel model is 15°, including 2 stationary blades 1 and 4 moving blades 2. The moving disc side bag-type structure 8 is located at the leading edge of the downstream moving blade 2 end, and a total of 4 moving disc side bag-type structures 8 are arranged along the circumferential direction, which is consistent with the number of blades of the moving blade 2 in the mainstream channel. The moving disc side bag-type structure 8 is located at the trailing edge of the upstream turbine stationary blade end, and a total of 2 stationary disc side bag-type structures 7 are arranged along the circumferential direction, which is consistent with the number of blades of the stationary blade 1 in the mainstream channel, refer to Figure 5 , Figure 6 and Figure 7 .

[0046] According to the structure of the present invention, the presence of the bag-type structures on both sides of the moving and static disks greatly prolongs the flow path of the gas invasion. When the mainstream gas invades the disk cavity through the wheel rim gap, the invading gas will first enter the bag-type structure 8 on the moving disk side, and violently mix with the sealed cold air flowing outward, forming multiple vortex structures, gradually dissipating the momentum of the gas invading radially inward; when the gas continues to invade inward into the disk cavity area 4, it further enters the bag-type structure 7 on the static disk side, where the invading gas and the sealed cold air are mixed to produce vortices, and gradually dissipate the momentum of the gas invading radially inward. At the circumferential position where the bag-type structure is not set, the sealed cold air will quickly pass through the sealing structure to impact the high-temperature gas at the wheel rim gap, and the cold air and gas will be violently mixed to prevent the gas from invading the disk cavity.

[0047] The wheel rim sealing structure of the present invention can be used in a gas turbine, and the gas turbine can be applied to a gas turbine, thereby improving the overall efficiency, operational reliability and stability of the gas turbine.

[0048] In summary, the present invention can effectively suppress the intrusion of gas into the disc cavity through the wheel rim gap without affecting the mainstream aerodynamic performance of the gas turbine, achieve better sealing effect with less sealing cold air volume, is beneficial to the protection of the hot end components of the gas turbine and the stable operation of the whole machine, significantly improves the efficiency and reliability of the gas turbine operation, and has important engineering application value and good engineering application prospects.

[0049] Embodiment 2

[0050] This embodiment discloses a turbine, including a double-sided bag-type rim sealing structure on the moving and stationary wheel disc surfaces.

[0051] The double-sided bag-type wheel rim sealing structure of the moving and static wheel disc surface includes a static disc 5 and a dynamic disc 6, a disc cavity area 4 is formed between the static disc 5 and the dynamic disc 6, a static disc side bag-type structure 7 is arranged on the side of the static disc 5, and a dynamic disc side bag-type structure 8 is arranged on the side of the dynamic disc 6. During operation, the sealed cold air is mixed with the fuel gas through the disc cavity area 4; the static disc side bag-type structure 7 is located on the wall of the static disc 5 near the wheel rim gap in the disc cavity area 4; the dynamic disc side bag-type structure 8 is located on the wall of the dynamic disc 6 in the wheel rim gap; the static disc side bag The bag-type structure 7 and the moving disk side bag-type structure 8 extend along the circumferential direction, perpendicular to or approximately perpendicular to the radial and axial directions of the turbine; each stator disk side bag-type structure 7 has a different circumferential angle θ3 and a different circumferential position angle θ4; each moving disk side bag-type structure 8 can have a different circumferential angle θ5 and a different circumferential position angle θ7; the stator disk side bag-type structure 7 and the moving disk side bag-type structure 8 have the same bag-type geometry type; the stator disk side bag-type structure 7 and the moving disk side bag-type structure 8 have arbitrary bag-type geometry parameters.

[0052] Embodiment 3

[0053] This embodiment discloses a gas turbine, including a turbine.

[0054] The present invention has the following characteristics:

[0055] The present invention arranges bag-type structures on the stationary disk surface near the rim gap in the disk cavity and on the wall surface of the moving disk 6 at the rim gap position, thereby changing the flow characteristics of high-temperature fuel gas intrusion and sealed cold air outflow, thereby effectively suppressing fuel gas from invading the disk cavity through the rim gap while hardly affecting the mainstream aerodynamic performance of the gas turbine, thereby achieving a better sealing effect with a smaller amount of sealed cold air.

[0056] The presence of the double-sided bag-type structure of the dynamic and static disks in the present invention greatly prolongs the flow path of the invading gas, so that the high-temperature gas invading into the disk cavity through the wheel rim gap can be more fully mixed with the outflowing sealed cold air, dissipating the momentum of the gas invading radially inward, and forming numerous vortices that hinder the gas from continuing to invade inward.

[0057] In the present invention, at the circumferential position where the bag-type structure is not arranged, the sealed cold air will quickly flow to the wheel rim gap through the sealing structure, impacting the high-temperature combustion gas, and the cold air and the combustion gas will be violently mixed, thereby preventing the combustion gas from invading the disc cavity.

[0058] In summary, the present invention can effectively suppress the intrusion of gas into the disc cavity through the wheel rim gap without affecting the mainstream aerodynamic performance of the gas turbine, and achieve a better sealing effect with a smaller amount of sealing cold air, which is beneficial to the protection of the hot end components of the gas turbine and the stable operation of the whole machine, and significantly improves the efficiency and reliability of the gas turbine operation, and has important engineering application value and significance.

[0059] Those skilled in the art will readily appreciate other embodiments of the present invention after considering the specification and disclosure of the invention. This application is intended to cover any variations, uses or adaptations of the present invention that follow the general principles of the present invention and include common knowledge or customary techniques in the art that are not disclosed by the present invention. The specification and examples are to be considered exemplary only, and the true scope and spirit of the present invention are indicated by the following claims.

[0060] It should be understood that the present invention is not limited to the exact construction that has been described above and shown in the drawings and that various modifications and changes may be made without departing from the scope thereof. The scope of the present invention is limited only by the appended claims.

[0061] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent structural change made to the above embodiment based on the technical essence of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A double-sided bag-type wheel rim sealing structure for a dynamic and static wheel disc, characterized in that: The invention comprises a stationary disk (5) and a moving disk (6), wherein a disk cavity region (4) is formed between the stationary disk (5) and the moving disk (6), a stationary disk side bag-type structure (7) is arranged on the side of the stationary disk (5), and a moving disk side bag-type structure (8) is arranged on the side of the moving disk (6). When working, the sealed cold air is mixed with the fuel gas through the disk cavity region (4).

2. The double-sided pocket-type wheel rim sealing structure of the dynamic and static wheel disc surface according to claim 1 is characterized in that: The stator disc side pocket-type structure (7) is located on the wall surface of the stator disc (5) near the wheel rim gap in the disc cavity area (4).

3. The double-sided pocket-type wheel rim sealing structure of the dynamic and static wheel disc surface according to claim 1 is characterized in that: The moving disc side pocket structure (8) is located on the wall surface of the moving disc (6) within the wheel rim gap.

4. The double-sided pocket-type wheel rim sealing structure of the dynamic and static wheel disc surface according to claim 1 is characterized in that: The stationary disc side bag-type structure (7) and the moving disc side bag-type structure (8) extend in the circumferential direction, perpendicular to or approximately perpendicular to the radial and axial directions of the turbine.

5. The double-sided pocket-type wheel rim sealing structure of the dynamic and static wheel disc surface according to claim 1 is characterized in that: Each of the stationary disc side pocket-type structures (7) has a different circumferential angle θ3 and a different circumferential position angle θ4.

6. The double-sided pocket-type wheel rim sealing structure of the dynamic and static wheel disc surface according to claim 1 is characterized in that: Each moving plate side pocket structure (8) has a different circumferential angle θ5 and a different circumferential position angle θ7.

7. The double-sided pocket-type wheel rim sealing structure of the dynamic and static wheel disc surface according to claim 1 is characterized in that: The bag-type structure (7) on the stationary disc side and the bag-type structure (8) on the moving disc side have the same bag-type geometry type.

8. The double-sided pocket-type wheel rim sealing structure of the dynamic and static wheel disc surface according to claim 1 is characterized in that: The bag-type structure (7) on the stationary disk side and the bag-type structure (8) on the moving disk side have arbitrary bag-type geometric parameters.

9. A turbine, characterized in that: It comprises the double-sided bag-type rim sealing structure of the dynamic and static wheel disc surface as described in any one of claims 1-8.

10. A gas turbine, characterized in that: Comprising the turbine as claimed in claim 9.

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