Turbine disk, turbine rotor and turbine engine
By designing tongue and grooves that extend in the axial direction and gradually decrease in cross-sectional area on the turbine disc, the problem of the need for an additional axial stop device in the prior art is solved, and the effect of preventing relative displacement of the tenon and tongue and groove is achieved, reducing weight and assembly difficulty, and improving the stability of the structure.
Patent Information
- Application Number
- CN202311769275.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-12-21
- Publication Date
- 2025-06-24
AI Technical Summary
In existing turbine engines, the connection between the rotor blades and the turbine disc requires additional axial stopping devices, resulting in increased manufacturing difficulty, increased weight, weak structure, increased assembly difficulty and increased fuel consumption.
A turbine disc is designed, which uniformly distributes a plurality of axially extending tongue and grooves on the outer circumference, and the cross-sectional area of the tongue and groove is from the insertion end to the other end. By this structure, the tenon of the blade is prevented from axially relative displacement from the tongue and groove of the turbine disc without the need for additional axial stopping devices.
Through this design, it is possible to prevent the axial relative displacement of the tenon and the tongue and groove without adding additional connection structures, reduce the weight of the turbine disc, reduce the difficulty of assembly and maintenance, and avoid the risk of damage of the axial stop device in high stress environments.
Smart Images
Figure CN120193885A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of turbine engines, especially aero-turbine engines, and more particularly to a tenon groove structure for connecting blades on a turbine disk. Background Art
[0002] Turbine components in a turbine engine, especially an aero-turbine engine, function to convert the internal energy of high-temperature and high-pressure gas into mechanical energy. The rotor blades and turbine disk of a power turbine operate under conditions of high temperature, high pressure, and high rotational speed for a long time, and thus bear huge centrifugal loads. Therefore, reducing the weight of the turbine rotor components, as well as the manufacturing and handling difficulties of the turbine rotor components, is of great significance to their working performance, cost, and entire service life cycle.
[0003] Currently, the rotor blades and the turbine disk are usually connected by a tenon joint. For this purpose, the blade includes a tenon head such as a dovetail tenon, and the tenon head generally has multiple trapezoidal or circular ridges or teeth symmetrically on both outer side walls. Correspondingly, the turbine disk includes a tenon groove for inserting the tenon head, and the tenon groove has sliding channels on both inner side walls that are symmetrically made with a number and profile matching the ridges or teeth of the tenon head. During operation, the blade is pushed by the high-temperature and high-pressure gas flow, driving the turbine disk to rotate together, and outputting torque to do work through the main shaft. In this process, the blade is subjected to a force along the axial direction, and relative displacement will occur between the tenon head of the blade and the tenon groove of the turbine disk. To prevent this axial relative displacement, in the prior art, it is known to use an axial stop device, such as an annular baffle, on the side of the turbine disk downstream in the gas flow direction.
[0004] However, using such an axial stop device requires adding additional connection structures to both the blade and the turbine disk simultaneously. This causes many problems, including increased manufacturing difficulty of the blade and the turbine disk, or additional weight, or weak local structure, or increased assembly difficulty, or increased fuel consumption, etc. Therefore, it brings limitations to the design and assembly of the parts, and there is also a risk of damage and failure of this device in a service environment that bears large stresses for a long time. Summary of the Invention
[0005] Due to the drawbacks of the additional axial stop device, it is desired to prevent the axial relative displacement between the tenon head of the blade and the tenon groove of the turbine disk in a simple, easy, and low-cost manner without using an axial stop device.
[0006] For this purpose, according to a first aspect of the present invention, there is provided a turbine disk, which includes a turbine disk body and a plurality of tenon grooves uniformly distributed on the outer circumference of the turbine disk body. The tenon grooves extend along the axial direction of the turbine disk and are used for installing blades. The blades are installed by inserting the tenon heads of the blades from a first end of the tenon groove to a second end of the tenon groove, and the cross-sectional area of the cross-section of the tenon groove perpendicular to the axial direction of the turbine disk is larger at the cross-section of the first end than at the cross-section of the second end.
[0007] By using the turbine disk according to the present invention, since the cross-sectional area of the dovetail groove of the turbine disk at the first end where the blade tenon is initially inserted is larger than the cross-sectional area at the second end where the blade tenon is inserted to the bottom, once the tenon of the blade is inserted in place in the dovetail groove, it will be restricted in the dovetail groove in the insertion direction of the tenon and it is difficult to move further in the insertion direction. Especially when the turbine rotor is installed such that the air flow acts on the turbine disk and the blade in the insertion direction of the tenon, that is, when the first end of the dovetail groove is located upstream of the air flow and the second end is located downstream of the air flow, due to the reduction of the cross-sectional area of the dovetail groove downstream of the air flow, the acting force of the air flow can make the tenon act like a wedge and be inserted more tightly in the dovetail groove, and it is less likely to have relative displacement. Thus, the effect of preventing axial relative displacement between the tenon and the dovetail groove is achieved through a simple and easy-to-manufacture tenon joint structure, so there is no need to provide any axial stop device on the side of the turbine disk located downstream of the air flow, thereby reducing the connection structure required on the blade and the turbine disk, reducing the weight of the turbine disk, and reducing the difficulty of assembly and maintenance. Moreover, compared with the prior art turbine disk using a unified axial stop device such as an annular baffle, the turbine disk according to the present invention can change the way that all the original blades are axially stopped by the same device to the way that each blade is axially stopped by the corresponding dovetail groove on the turbine disk. Thus, the problem that the axial stops of all the blades fail due to damage caused by fatigue, collision accidents, etc. in the service environment where the axial stop device bears large stresses for a long time is avoided.
[0008] The turbine disk according to the present invention may further include one or more of the following optional features individually or in combination.
[0009] Preferably, the cross-sectional area of the dovetail groove perpendicular to the axial direction of the turbine disk gradually decreases in the direction from the first end to the second end. The dovetail groove with a gradually decreasing cross-section can further enhance the effect of preventing axial relative displacement of the tenon, making the tenon inserted more tightly like a "wedge" once it is inserted into the dovetail groove.
[0010] Preferably, the two side edges of each longitudinal section of the dovetail groove perpendicular to the radial direction of the turbine disk are two straight lines, and these two straight lines intersect after extension and the included angle is between 1° and 12°, for example 5°. In other words, when looking down from above at the upright turbine disk according to an embodiment of the present invention, it is observed that the two side edges constituting the contour of the dovetail groove are not parallel, but the included angle should not be too large, and an overly large included angle will limit the length and function of the dovetail groove. In practice, an included angle between 1° and 12°, such as 5°, has obtained good results.
[0011] Preferably, the dovetail groove is a straight dovetail groove. Alternatively, the dovetail groove is a curved dovetail groove. Whether to adopt a straight dovetail groove or a curved dovetail groove depends on different designs of the turbine disk.
[0012] According to a second aspect of the present invention, there is provided a turbine rotor, which includes the turbine disk described above and a plurality of blades mounted on the turbine disk. The blades include a blade body and a tenon that is tenon-mortise matched with the mortise groove of the turbine disk.
[0013] According to a third aspect of the present invention, there is also provided a turbine engine, which includes the turbine rotor described above. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] In order to more clearly describe the technical solutions of the embodiments of the present invention, the following will briefly describe the drawings required for the description of the embodiments. It is easy for those skilled in the art to understand that these drawings are only for illustrative purposes and are not intended to limit the protection scope of the present invention. For illustrative purposes, these figures may not be drawn to scale exactly. In the drawings:
[0015] Figure 1 is a schematic perspective view of a turbine disk according to an embodiment of the present invention;
[0016] Figure 2 is a schematic perspective view of a blade of a turbine rotor according to an embodiment of the present invention;
[0017] Figure 3 is a schematic front view of a part of a turbine disk and a blade assembled together according to an embodiment of the present invention;
[0018] Figure 4 is a schematic perspective view of a turbine rotor according to an embodiment of the present invention;
[0019] Figure 5 is a schematic partial enlarged view of a turbine disk according to an embodiment of the present invention, which shows the mortise groove;
[0020] Figure 6 is a schematic top view of the mortise groove of a turbine disk according to an embodiment of the present invention;
[0021] Figure 7 is a schematic simplified view of a curved mortise groove of a turbine disk according to an embodiment of the present invention.
[0022] In different drawings, unless otherwise specified, the same reference numerals represent the same or similar elements. The list of reference numerals is as follows: 1 turbine disk; 10 turbine disk body; 11 mortise groove; 111 first end of the mortise groove; 112 second end of the mortise groove; 13 slideway; 114, 115 projection lines of the inner side wall of the mortise groove; 2 blade; 20 blade body; 21 tenon; 22 convex rib or tooth; X axial direction of the turbine disk; Y tangential direction of the turbine disk; Z radial direction of the turbine disk. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0023] The present invention will be further described in detail below with reference to the accompanying drawings in conjunction with exemplary embodiments.
[0024] Although terms such as "first" and "second" may be used herein to describe various elements, these terms are only used to distinguish one element from another and do not indicate any order in time, space or logic between these elements. Therefore, the first and the second as referred to herein may be interchanged without departing from the teachings of the examples.
[0025] Herein, unless the context clearly indicates otherwise, the singular forms are also intended to include the plural forms. The term "plurality" represents any quantity among two and more than two. Terms such as "comprising", "including" and "having" etc. illustrate the existence of the recited features, quantities, operations, components, elements and / or their combinations, but do not exclude the existence of one or more other features, quantities, operations, components, elements and / or their combinations.
[0026] It should be understood that unless otherwise defined, all terms used herein, including technical terms and scientific terms, have the same meaning as commonly understood by those of ordinary skill in the art to which the present invention pertains after understanding the present invention. In addition, in the description of the examples, when it is considered that the detailed description of the related structures or functions known to the public will cause a vague interpretation of the present invention, such detailed description will be omitted.
[0027] The X, Y and Z directions mentioned herein are defined with reference to a three-dimensional coordinate system (see Figure 3 ), wherein the X direction is defined as the axial direction of the turbine disk, and thus for simplicity, the Y direction is referred to as the tangential direction of the turbine disk and the Z direction is referred to as the radial direction of the turbine disk.
[0028] Figure 1 A perspective view of a turbine disk 1 according to an embodiment of the present invention is schematically shown. The turbine disk 1 includes a turbine disk body 10 and a plurality of tenon grooves 11 uniformly distributed on the outer circumference of the turbine disk body 10 for mounting rotor blades. Figure 5A partial enlarged view of the turbine disk 1 is schematically shown. As shown in the figure, these dovetail grooves 11 are the same as each other and each extends along the axial direction X of the turbine disk. Different from the dovetail grooves in the prior art whose cross-sections perpendicular to the axial direction X are equal everywhere, that is, the thickness or the width is the same, the cross-sectional area of the dovetail groove 11 designed according to the present invention is not consistent from the starting end of the extension, that is, the first end 111, to the opposite end, that is, the second end 112. Instead, the cross-sectional area is larger at the starting end 111 and becomes smaller at the end, that is, the second end 112. According to a preferred embodiment, as shown in the figure, the cross-sectional area of the dovetail groove 11 can gradually become smaller in the axial direction X from the first end 111 to the second end 112. In other words, the dovetail groove 11 gradually tapers or becomes narrower. Those skilled in the art should understand that after the turbine disk 1 is installed, the direction of the high-temperature and high-pressure air flow blowing is the same as the direction from the first end 111 to the second end 112 of the dovetail groove 11, and this direction is Figure 1 in the direction of the lower right in the figure along the axial direction X.
[0029] Figure 2 A three-dimensional view of the rotor blade 2 of the turbine rotor according to an embodiment of the present invention is schematically shown. The blade 2 includes a blade body 20 and a tenon 21 for inserting into the dovetail groove 11 of the turbine disk 1. The tenon 21 generally adopts a fir tree type design that is symmetric on both sides and / or adopts a dovetail design. According to a specific embodiment, at least one convex rib or tooth 22 is respectively manufactured on the two outer side walls of the tenon 21. Correspondingly, as shown in Figure 5 the figure, at least one slideway 13 is manufactured on the two inner side walls constituting the dovetail groove 11 for cooperating with the convex rib or tooth 22 on the tenon 21 to enhance the anti-disengagement effect of the connection between the tenon 21 and the dovetail groove 11. In view of the large centrifugal force and other stresses during the operation of the turbine rotor, the number of the slideways 13 or the convex ribs 22 on each side can be 2, 3, 4, etc. And the angles, lengths or depths of the concavities and convexities of the slideways 13 and the convex ribs or teeth 22 can be designed to overcome or disperse the stresses.
[0030] Thus, according to the present invention, as shown in Figure 3 the figure, when the tenon 21 of the blade 2 that is tenon-jointed and matched with the dovetail groove 11 of the turbine disk 1 is inserted along the axial direction X from the first end 111 to the second end 112 of the dovetail groove 11 with force, because the cross-sectional area of the dovetail groove 11 becomes smaller, the tenon 21 will be restricted in the dovetail groove 11 and inserted tightly. And when it is subjected to a force in the same direction as the insertion direction, such as the force of the high-temperature and high-pressure air flow, the greater the force, the tighter it can be inserted. Thus, the excellent firm connection effect of the tenon-joint structure can be exerted to prevent relative displacement between the tenon 21 and the dovetail groove 11 in the axial direction X. In this way, after the blades 2 are successively installed on the turbine disk 1, the turbine rotor as shown in Figure 4 the figure will be obtained. In Figure 4It can be seen that the turbine disc 1 does not have an axial stop device such as an annular baffle in the prior art on the side of the turbine disc 1 located downstream of the air flow, i.e., the side shown in the figure. Therefore, the structure of the turbine rotor is not only lighter, easier to manufacture, assemble and maintain, and has lower fuel consumption than the prior art, but also has the same or even better effect of preventing the axial relative displacement of the tenon and the tenon groove.
[0031] Continue to refer to Figure 6 , which schematically shows the outline of the tenon groove 11 on the upright turbine disk 1 when looking down from a direction roughly perpendicular to the axial direction X in one embodiment of the present invention. It can be seen that the visual projections of the two inner side walls of the tenon groove 11 are two straight lines 114 and 115, and these two straight lines are not parallel, and the angle between them is 5° in the illustrated example. That is to say, the tenon groove 11 in this example gradually becomes smaller in the insertion direction of the tenon 21 parallel to the axial direction X, and the sum of the angles at which the two inner sides of the tenon groove 11 are narrowed relative to the axial direction X is 5°. In practice, good results are achieved with an angle between 1° and 12°. It should be understood that although Figure 6 Because the inner wall of the mortise and tenon 11 includes the slide 13 and has more than one projection straight line and the top view angle is not absolutely vertical, it seems that each mortise and tenon 11 does not become smaller in the same manner, but in fact in this embodiment they become smaller uniformly and consistently in the same direction and amplitude.
[0032] Although the mortise and tenon grooves 11 in the illustrated embodiment are all linear mortise and tenon grooves, the present invention is not limited thereto. Figure 7 As shown in FIG. 1 , the tongue and groove 11 of the turbine disk 1 can also be designed as a curved tongue and groove, wherein the curved course of the tongue and groove 11 is schematically shown by a bold bold line.
[0033] In addition, the above embodiments introduce the tenon joint structure between the turbine disk and the blades using the turbine rotor of a turbine engine as the application scenario. However, it should be understood that the tenon joint structure according to the present invention can also be applied to other equipment requiring axial stop, such as the assembly of fan blades, when appropriate.
[0034] The above non-limiting embodiments of the present invention are described in detail, wherein some conventional technical contents in the prior art are simplified or omitted in order to teach the principles of the present invention. It should be understood by those skilled in the art that the different features described above with reference to a plurality of embodiments can be combined in various ways to form more embodiments of the present invention. Moreover, those skilled in the art can make various modifications, substitutions and variations to the above embodiments without departing from the spirit and thought of the present invention. Therefore, the present invention is not limited to the above embodiments, but is only limited by the attached claims and their equivalents.
Claims
1. A turbine disk, the turbine disk (1) comprising a turbine disk body (10) and a plurality of dovetail grooves (11) uniformly distributed on the outer circumference of the turbine disk body (10), the dovetail grooves (11) extending along the axial direction (X) of the turbine disk (1) and being used for installing blades (2), and the blades (2) being installed by inserting the tenons (21) of the blades (2) from a first end (111) of the dovetail grooves (11) to a second end (112) of the dovetail grooves (11), characterized in that, The area of the cross-section of the tenon groove (11) perpendicular to the axial direction (X) of the turbine disk (1) is larger at the cross-section at the first end (111) than at the cross-section at the second end (112).
2. The turbine disk according to claim 1, wherein, The area of the cross-section of the tenon groove (11) perpendicular to the axial direction (X) of the turbine disk (1) gradually decreases in the direction from the first end (111) to the second end (112).
3. The turbine disk according to claim 2, wherein, The two side edges of each longitudinal section of the tenon groove (11) perpendicular to the radial direction (Z) of the turbine disk (1) are two straight lines, and after these two straight lines are extended, they intersect and the included angle is between 1° and 12°.
4. The turbine disk according to claim 3, wherein, The included angle is 5°.
5. The turbine disk according to any one of claims 1 to 4, wherein, The tenon groove (11) is a straight tenon groove.
6. The turbine disk according to any one of claims 1 to 4, wherein, The tenon groove (11) is a curved tenon groove.
7. A turbine rotor, which includes the turbine disk (1) as described in any one of claims 1 to 6 and a plurality of blades (2) installed on the turbine disk (1), and the blades (2) include a blade body (20) and a tenon head (21) that is tenon-jointed and matched with the tenon groove (11) of the turbine disk (1).
8. A turbine engine, including the turbine rotor as described in claim 7.