A turbine guide vane and turbine guide

Abstract

The application provides a turbine guide vane and a turbine guide, and relates to the technical field of gas turbines. The turbine guide vane comprises an upper edge plate, a lower edge plate and a blade body, the blade body is fixed between the upper edge plate and the lower edge plate, a hollow cavity is radially formed in the inside of the blade body, the blade back and the blade basin of the blade body are smoothly connected through an arc-shaped leading edge and a trailing edge, the shape of the hollow cavity is completely the same as the shape of the blade body, and a stress relief groove is formed on the inner wall of the hollow cavity and corresponds to the position of the leading edge of the blade body. The turbine guide vane structure can effectively release the radial thermal stress of the middle part of the leading edge of the turbine guide vane, thereby reducing the stress level of the middle part of the leading edge of the turbine guide, optimizing the problem of local stress concentration of the guide vane, and prolonging the service life of the turbine guide.

Description

Technical Field

[0001] This invention relates to the field of gas turbine technology, and more specifically to a turbine guide vane and a turbine guide vane. Background Technology

[0002] A gas turbine is a mechanical device that uses the energy of natural gas to generate power. In a gas turbine, natural gas is compressed by a compressor, mixed with air, and burned at high temperatures in a combustion chamber. The high-temperature gases produced by combustion flow through a turbine, causing the turbine to rotate, which in turn drives the entire rotor to rotate via the main shaft.

[0003] A gas turbine turbine consists of two parts: a rotor and a stator. The stator includes the turbine guide vane. Although the turbine guide vane is a stationary component, its operating conditions are extremely harsh, and the mechanical properties of the material degrade rapidly at high temperatures. Furthermore, the combustion chamber outlet temperature is not spatially uniform, with higher temperatures in the center and lower temperatures at the edges, creating a significant temperature gradient in the radial direction. This temperature gradient causes substantial thermal stress on the leading edge of the guide vane blades. In practical applications, this thermal stress can cause cracks in the middle of the guide vane's leading edge, leading to guide vane failure.

[0004] Currently, most turbine guide vanes, both domestically and internationally, typically reduce blade stress by adding special structures to the upper and lower edge plates or by altering the specific structure connecting them to other components. However, due to space limitations, modifying these structures is constrained by component dimensions and assembly relationships with adjacent components, making such adjustments difficult to implement. Furthermore, this method can only improve overall blade stress and is unlikely to improve localized blade stress. Summary of the Invention

[0005] In view of this, embodiments of this application provide a turbine guide vane and a turbine guide vane to release the radial thermal stress in the middle of the leading edge of the turbine guide vane, thereby reducing the stress level in the middle of the leading edge of the turbine guide vane, optimizing the problem of local stress concentration in the guide vane, and extending the service life of the turbine guide vane.

[0006] This application provides the following technical solution: a turbine guide vane, comprising: an upper edge plate, a lower edge plate, and a blade body, wherein the blade body is fixed between the upper edge plate and the lower edge plate;

[0007] The interior of the leaf has a hollow cavity formed radially. The back of the leaf and the leaf base are smoothly connected by the leading and trailing edges of the arc surface. The shape of the hollow cavity is exactly the same as the shape of the leaf.

[0008] Stress-relieving grooves are formed on the inner wall of the hollow cavity at the position corresponding to the leading edge of the blade.

[0009] According to one embodiment of this application, the stress-relieving groove is formed at the middle of the leading edge in the height direction of the blade.

[0010] According to one embodiment of this application, the stress-relieving groove and the hollow cavity are smoothly connected by a circular arc surface.

[0011] According to one embodiment of this application, the maximum depth of the stress-relieving groove is... Where H is the blade height.

[0012] According to one embodiment of this application, the groove width h of the stress-relieving groove satisfies: 2d≤h≤5d; where h is the groove width of the stress-relieving groove and d is the maximum depth inside the stress-relieving groove.

[0013] According to one embodiment of this application, the wall thickness t = 0.08H at the leading edge of the blade; where H is the blade height.

[0014] According to one embodiment of this application, the minimum value of the blade wall thickness T is 3 mm.

[0015] This application also provides a turbine guide, which includes turbine guide blades as described above.

[0016] Compared with the prior art, the beneficial effects achieved by at least one of the above-mentioned technical solutions adopted in the embodiments of this specification include at least the following: The embodiments of this invention propose a turbine guide vane with a thermal stress relief cavity. This turbine guide vane includes an inner cavity with a groove at the center of its leading edge. By designing the groove, the constraint caused by temperature-induced deformation can be reduced, allowing the radial stress at the center of the leading edge of the turbine guide vane to be released, thereby reducing the stress level at the center of the leading edge of the turbine guide vane and extending the service life of the turbine guide vane. Furthermore, by adjusting the wall thickness at different locations, the wall thickness is increased at locations with higher stress to achieve local reinforcement. The embodiments of this invention reduce local stress on the blade by changing the blade cavity geometry, including the wall thickness at different locations and the creation of stress-relieving grooves, without changing the blade's shape (and without affecting aerodynamic performance) or assembly structure. At the same time, because the turbine guide vane has a hollow internal structure, the overall weight of the guide vane is reduced, achieving weight reduction for the turbine and the entire gas turbine. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of a gas turbine structure;

[0019] Figure 2 This is a schematic diagram of the turbine structure of a gas turbine.

[0020] Figure 3 This is a schematic diagram of the turbine guide vane structure according to an embodiment of the present invention;

[0021] Figure 4 This is a schematic diagram of the cross-sectional structure of the turbine guide vane according to an embodiment of the present invention;

[0022] Figure 5 This is a schematic diagram of the internal structure of the turbine guide vane according to an embodiment of the present invention;

[0023] Figure 6 yes Figure 5 A schematic diagram of a local structure in the image;

[0024] Figure 7 This is a schematic diagram of the overall structure of the hollow cavity and stress-relief groove inside the turbine guide vane according to an embodiment of the present invention;

[0025] Figure 8 This is a schematic diagram of the turbine guide structure according to an embodiment of the present invention;

[0026] Among them, 1-compressor, 2-combustion chamber, 3-turbine, 4-main shaft, 5-turbine guide vane, 6-rotor, 7-upper edge plate, 8-blade body, 81-leading edge, 82-tailing edge, 83-blade basin, 84-blade back, 9-lower edge plate, 10-hollow cavity, 11-stress relief groove. Detailed Implementation

[0027] The embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0028] The following specific examples illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. This application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0029] like Figures 1-2As shown, in a gas turbine, the gas is compressed by compressor 1 and mixed with air, then burned at high temperature in combustion chamber 2. The high-temperature gas produced by combustion flows through turbine 3, causing turbine 3 to rotate, which in turn drives the entire rotor to rotate via main shaft 4. The gas turbine includes two parts: rotor 6 and stator. The stator part includes turbine guide vanes 5.

[0030] like Figures 3-7 As shown, an embodiment of the present invention provides a turbine guide vane, comprising: an upper edge plate 7, a lower edge plate 9, and a blade 8, wherein the blade 8 is fixed between the upper edge plate 7 and the lower edge plate 9; a hollow cavity 10 is radially formed inside the blade 8, and the blade back and blade base of the blade 8 are smoothly connected by an arc-shaped leading edge 81 and a trailing edge 82, and the outer shape of the hollow cavity 10 is exactly the same as the outer shape of the blade 8; a stress-relieving groove 11 is formed in the hollow cavity 10 at a position corresponding to the leading edge 81 of the blade 8.

[0031] This invention relates to a turbine guide vane with a thermal stress relief cavity. The blades of this turbine guide vane have a hollow cavity 10 inside, and this hollow cavity 10 has a groove in the middle of its leading edge 81. The hollow cavity 10 and the groove reduce the constraint caused by temperature-induced deformation, thereby releasing stress in the middle of the leading edge 81 of the turbine guide vane, reducing the stress level in the middle of the leading edge 81, and extending the service life of the turbine guide vane. At the same time, because the interior of the turbine guide vane blade is hollow, the overall weight of the guide vane is reduced, achieving a weight reduction effect on the turbine and the entire gas turbine.

[0032] The turbine guide vane and turbine guide vane constituted by the present invention are particularly suitable for smaller engines. Smaller engines have limited space between their upper and lower edge plates, making it difficult to design structures at these plates to release thermal stress. For example, existing technologies typically use cooling structures between the upper and lower edge plates to address thermal stress concentration. While cooling can reduce temperature and thus stress, designing cooling channels within the limited structural space is difficult for smaller engines. Furthermore, current optimizations of the upper and lower edge plate structures only improve the overall thermal stress of the guide vane and cannot optimize localized thermal stress. Therefore, the turbine guide vane of this embodiment has a radially formed hollow cavity 10 inside the blade, and a stress-relieving groove 11 at the location of highest stress concentration on the leading edge 81 of the blade body 8. When the blade expands under high temperature, especially when the temperature is high in the middle of the leading edge 81 and the expansion tendency is greater, while the temperature is low on both sides and the expansion tendency is smaller, the design of the stress-relieving groove 11 allows for freer deformation of the leading edge 81, thereby releasing the stress in the middle of the leading edge 81. This embodiment releases radial thermal stress by changing the structure without altering the temperature field. The structural design of this embodiment reduces the stress in the middle of the leading edge of the blade by more than 10%.

[0033] In practical implementation, because the temperature is high in the middle of the combustion chamber outlet and low on both sides, the temperature is highest in the middle of the leading edge 81 of the blade, where thermal stress is most concentrated. Therefore, by opening the stress-relieving groove 11 in the middle of the leading edge 81 along the height direction of the blade body 8, radial thermal stress can be effectively released, reducing the stress level in the middle of the turbine guide vane leading edge 81. Since the height position of the stress-relieving groove 11 is the same as the position with the highest incoming gas temperature, in other embodiments, the specific position of the stress-relieving groove 11 can be set according to the position with the highest incoming gas temperature.

[0034] In practice, the stress-relieving groove 11 and the hollow cavity 10 are smoothly connected by a circular arc surface, so that the stress is released evenly.

[0035] In practical implementation, to ensure the strength of the turbine guide vanes and the overall reliability of the turbine guide vane, the structural dimensions of the stress-relieving groove 11 need to be strictly designed. In this embodiment, the maximum depth of the stress-relieving groove 11 is... The groove width h of the stress-relieving groove 11 satisfies: 2d≤h≤5d; where h is the groove width of the stress-relieving groove, d is the maximum depth of the stress-relieving groove, and H is the blade height.

[0036] Furthermore, to ensure the strength of the turbine guide vanes and the overall reliability of the turbine guide vane, the dimensions of the hollow cavity 10 inside the blade body 8 also need to be strictly designed. The blade body 8 includes a leading edge 81, a trailing edge 82, a blade base 83, and a blade back 84. The shape of the hollow cavity 10 is consistent with the shape of the blade body 8, and the opening of the hollow cavity 10 needs to ensure that the wall thickness t = 0.08H at the leading edge 81 of the blade body 8; where H is the blade height. This wall thickness design can meet the strength requirements at the leading edge position.

[0037] In practical implementation, the wall thickness of the leaf blade 8 differs between the leaf base and the leaf back, with a thicker wall thickness applied to areas of higher stress. For example, in this embodiment, the stress is higher on the leaf back, hence the wall thickness is thicker there. This provides localized reinforcement to the leaf back area, reducing stress there. Furthermore, the wall thickness can be adjusted at different locations to increase the wall thickness in areas of higher stress, achieving a similar effect of localized reinforcement.

[0038] In this embodiment, the minimum wall thickness T of the blade is preferably 3 mm.

[0039] like Figure 8 As shown, the turbine guide vane of this embodiment includes multiple turbine guide vane blades as described above. These blades have identical structures, all containing the same hollow cavity and stress-relief grooves. This embodiment of the invention reduces localized stress on the blades by altering the blade cavity geometry, including varying wall thicknesses at different locations and creating stress-relief grooves, without changing the blade shape (or affecting aerodynamic performance) or the assembly structure. Simultaneously, because the turbine guide vane has a hollow internal structure, the overall weight of the guide vane is reduced, achieving weight reduction for the turbine and the entire gas turbine.

[0040] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A turbine guide vane, characterized in that, include: The blade consists of an upper edge plate, a lower edge plate, and a blade body, wherein the blade body is fixed between the upper edge plate and the lower edge plate. The interior of the leaf has a hollow cavity formed radially. The back of the leaf and the leaf base are smoothly connected by the leading and trailing edges of the arc surface. The shape of the hollow cavity is exactly the same as the shape of the leaf. A stress-relieving groove is formed on the inner wall of the hollow cavity at the position corresponding to the leading edge of the blade. The stress-relieving groove is formed at the middle of the leading edge in the height direction of the blade. The stress-relieving groove and the hollow cavity are smoothly connected by a circular arc surface; The maximum depth of the stress-relieving groove d ;in, H The height of the leaf blade; The groove width of the stress-relief groove h satisfy: ;in, d This represents the maximum depth within the stress-relief groove. The wall thickness at the leading edge of the blade t=0.08H .

2. The turbine guide vane according to claim 1, characterized in that, The blade wall thickness T The minimum value is 3mm .

3. A turbine guide, characterized in that, The turbine guide includes the turbine guide blade as described in claim 1.

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