Cooling turbine rotor blade

Abstract

The invention discloses a cooling turbine rotor blade and belongs to the technical field of aero-engines, the cooling turbine rotor blade is mounted in a mortise of a turbine disc through a tenon, the rotor blade is provided with a cooling structure, the mounting angle of the lower section of the rotor blade at any height position is 50-60 degrees, and the number of the rotor blade is 40-45. By limiting the mounting angles of the sections of the rotor blades and the number of the blades, the whole rotor blades can be designed to be approximately linear, the twisting degree of the blades is small, the change of the whole height of the rotor blades is small, the design of a rotor blade cooling structure can be better facilitated, heat dissipation of the rotor blades in a high-temperature environment is guaranteed, and the service life of the rotor blades is prolonged. And meanwhile, the secondary flow loss of the rotor blade is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of aeroengines, and in particular relates to a cooling turbine rotor blade. Background Art

[0002] At present, one of the development trends of aerodynamic design of turbine components is ultra-high-load, high-throughput and high-efficiency design technology. The realization of high-load and high-efficiency turbine design mainly relies on high-load blade design technology, or increasing the turbine stage load factor and reducing the turbine size, thereby effectively reducing the engine weight. For high-load and high-throughput turbine design schemes, the airflow Mach number of the high-load factor turbine design will exceed the traditional design experience range and reach supersonic speed; in addition, high-throughput turbine design means that the blade aspect ratio is reduced, the turbine secondary flow loss is increased, and the efficiency of the turbine is reduced.

[0003] In order to achieve the design purpose, each stage of the turbine components must meet many specific requirements, including comprehensive improvement of aerodynamic efficiency, aerodynamic load, mechanical load, blade size, structural strength, cooling design, so the high-pressure turbine rotor blades must meet the requirements of efficiency, thermal load, strength life, throat area, blade thickness, outlet airflow angle, etc. The blade design needs to balance between aerodynamics, cooling and structural strength. Under high load factor and high flow conditions, the existing turbine blades have serious secondary flow, large blade shock wave loss, large cold air mixing loss, and low turbine efficiency; under high temperature conditions, the blade cooling effect is poor, easy to ablate, and the life is short. Summary of the invention

[0004] The object of the present invention is to provide a cooling turbine rotor blade. Through the design of the present invention, the contradictions among turbine aerodynamics, cooling, structural strength, weight, processing technology and cost are better balanced, so as to solve the problems of severe secondary flow, difficult cooling structure design and poor cooling effect of existing rotor blades proposed in the above background technology.

[0005] To achieve the above-mentioned purpose, the present invention provides the following technical solution: a cooling turbine rotor blade, wherein the rotor blade is installed in the tenon of the turbine disk through a tenon, the rotor blade is provided with a cooling structure, the installation angle of the cross section of the rotor blade at any height position is 50 to 60°, and the number of the rotor blades is 40 to 45.

[0006] Furthermore, the cross-sectional radius of the rotor blade is 110-140 mm.

[0007] Furthermore, the chord length of the cross section of the rotor blade at any height position is 25 to 27 mm.

[0008] Furthermore, the rotor blade has a blade tip and a blade root in the radial direction, and the chord length of the cross section of the blade tip is greater than the chord length of the cross section of the blade root.

[0009] Furthermore, the pitch of the rotor blades is 17-22 mm.

[0010] Furthermore, the inlet structural angle of the cross section of the rotor blade at any height position is 50 to 80 degrees, and the outlet structural angle is 30 to 40 degrees.

[0011] Furthermore, the rotor blade has a blade tip and a blade root in the radial direction, and an outlet configuration angle of a cross section of the blade tip is greater than an outlet configuration angle of a cross section of the blade root.

[0012] Furthermore, the rotor blade has a blade tip and a blade root in the radial direction, the maximum thickness of the blade tip section is 4.5 to 5 mm, and the ratio of the blade root section to the blade tip section is 1.2 to 1.3.

[0013] Furthermore, the rotor blade has a tip portion and a root portion in the radial direction, and a leading edge portion and a trailing edge portion in the axial direction, and the cooling structure includes a groove and a cooling hole formed at the tip portion, a slit formed at the trailing edge portion, and a channel formed in the rotor blade for connecting the cooling hole and the slit.

[0014] Furthermore, the split seam is a half split seam structure.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] 1. By limiting the installation angle of the rotor blade cross section and the number of blades, the present application can make the rotor blade as a whole be designed to be approximately linear, with a small degree of blade distortion and a small change in the overall height of the rotor blade, which can be more conducive to the design of the rotor blade cooling structure, ensuring the heat dissipation of the rotor blade in a high temperature environment, while reducing the shock wave loss of the rotor blade. Based on this design, the tenon can wrap the root of the rotor blade, which is conducive to reducing the weight of the engine and optimizing the processing technology of the rotor blade.

[0017] 2. The present application limits the chord length of the rotor blade at the overall height, and the axial chord length of the turbine rotor blade varies little in the entire blade height range. Increasing the chord length and thickness of the blade tip can reduce the aerodynamic load level at the blade tip, reduce the lateral pressure gradient, and thereby significantly reduce gap leakage losses, while reducing secondary flow losses. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A cross-sectional view of the connection between the rotor blade and the turbine disk;

[0019] Figure 2 is a three-dimensional schematic diagram of a rotor blade;

[0020] Figure 3 It is a schematic diagram of the cross section of the leaf tip, leaf middle and leaf root;

[0021] Figure 4a This is a schematic diagram of the installation of the rotor blade tenon;

[0022] Figure 4b It is a schematic diagram of the cross section of the bottom of the tenon;

[0023] Figure 5 is a schematic diagram of rotor blade cross-section parameters;

[0024] Figure 6a It is a schematic diagram of the secondary flow area of ​​the prior art;

[0025] Figure 6b Schematic diagram of the secondary flow area of ​​this application.

[0026] In the figure:

[0027] 10. Rotor blade; 100. Blade tip; 101. Blade root; 102. Leading edge; 103. Trailing edge; 104. Tenon; 105. Edge plate; 106. Groove; 107. Cooling hole; 108. Slit; 109. Baffle; 110. Turbine disk; 111. Tenon and groove. 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 only 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] A cooling turbine rotor blade (hereinafter referred to as rotor blade), in some embodiments, refers to Figure 1 , is a schematic cross-sectional view of the assembly of the rotor blade 10 and the turbine disk 110. As can be seen from the figure, the rotor blade 10 is installed in the tenon groove 111 of the turbine disk 110 through the tenon 104, and the turbine disk 110 is provided with a baffle 109 on at least one side in the axial direction to prevent the rotor blade 10 from moving in the axial direction. For example, the tenon 104 is a two-tooth structure, and the rotor blade 10 is installed on the turbine disk 110 through the fir-tree-shaped tenon teeth, and is limited and pressed by the baffle 109 to form a turbine rotor. Return to Figure 1 , and combined with Figure 2(i.e., a three-dimensional schematic diagram of a rotor blade 10), in some embodiments, the rotor blade 10 is connected to the tenon 104 through an edge plate 105. Specifically, the edge plate 105 has two mounting surfaces arranged opposite to each other in the thickness direction, and the rotor blade 10 and the tenon 104 are respectively assembled on the two mounting surfaces. Further, the rotor blade 10 has a blade tip 100 and a blade root 101 in the radial direction, wherein the blade root 101 constitutes a contact position between the rotor blade 10 and the edge plate 105, and the rotor blade 10 has The leading edge portion 102 and the trailing edge portion 103, in some embodiments, the rotor blade 10 is provided with a cooling structure, the cooling structure comprising a groove 106 and a cooling hole 107 arranged on the blade tip portion 100, and a cooling channel (not shown) is formed inside the rotor blade 10, and a slit 108 is formed corresponding to the trailing edge portion 103 of the rotor blade 10, illustratively, the diameter of the cooling hole 107 is 0.4-0.5 mm, the depth of the groove 106 is less than 1 mm, and during the operation of the engine, the cooling gas is discharged from the bottom of the tenon 104 (see Figure 4b ) enters the rotor blade 10 to cool the rotor blade 10 and then flows out from the slit 108 of the trailing edge 103. In some examples, the slit 108 of the trailing edge 103 is a half-slit design to further reduce the trailing edge thickness, reduce shock wave losses and mixing losses, and improve the cooling effect.

[0030] Reference Figure 5 , is a schematic cross-sectional view of the rotor blade 10 at any height position, in which the θ axis and the X axis represent the circumferential direction and the axial direction (based on the turbine shaft direction), respectively. Figure 3 The cross sections at the tip, middle and root of the rotor blade are given as examples. Figure 5 The middle dotted line is the middle arc line of the rotor blade 10 at the cross-sectional position, that is, the line connecting the centers of all inscribed circles between the two profile lines of the rotor blade 10 .

[0031] Figure 5β1k represents the inlet structural angle of the rotor blade 10 at the cross-sectional position, that is, the angle between the tangent line of the middle arc line at the leading edge 102 and the θ axis, and β2k represents the outlet structural angle of the rotor blade 10 at the cross-sectional position, that is, the angle between the tangent line of the middle arc line at the trailing edge 103 and the θ axis; in some embodiments, at the entire height of the rotor blade 10, the inlet structural angle of any cross section of the rotor blade 10 is 50-80°, and the outlet structural angle is 30-40°. Based on the angle design of the inlet structural angle and the outlet structural angle of the rotor blade 10, it is possible to reduce The turning angle of the low airflow passing through the rotor blade 10 can reduce the lateral pressure gradient, which is beneficial to reducing the secondary flow loss and has a positive effect on the air film coverage effect of the rotor blade 10. In some embodiments, the outlet structural angle of the cross section at the tip 100 position is greater than the outlet structural angle of the cross section at the root 101 position, which is used to increase the reaction force at the root of the rotor blade 10, so that the blade groove converges well and the root of the rotor blade 10 has better acceleration; at the same time, for high reaction force turbines, the tip aerodynamic load can be reduced, reducing the leakage loss of the tip 100.

[0032] In the figure, b represents the chord length of the cross section of the rotor blade 10 at any height position, that is, the length of the line connecting the two end points of the mid-arc line; in some embodiments, at the overall height of the rotor blade 10, the chord length of any cross section of the rotor blade 10 is 25-27 mm, that is, the chord length of the rotor blade 10 varies less at the overall height of the rotor blade 10, and the chord length of the cross section of the blade tip 100 is greater than the chord length of the cross section of the blade root 101. Further, the axial chord length of any cross section position of the rotor blade 10 is 20-23 mm. Further, Figure 5 Where tmax represents the maximum thickness of the rotor blade 10 at this cross-sectional position, that is, the diameter of the maximum inscribed circle of the rotor blade 10 at this cross-sectional position. The maximum thickness of the above-mentioned tip portion 100 cross section is 4.5-5 mm. The design based on the length limitation of the chord length and the thickness limitation of the tip portion 100 can reduce the aerodynamic load level of the tip, reduce the lateral pressure gradient, and thus significantly reduce the gap leakage loss, while reducing the secondary flow loss.

[0033] Furthermore, the ratio of the cross-sectional area of ​​the blade root 101 to the cross-sectional area of ​​the blade tip 100 is between 1.2 and 1.3, and the ratio of the cross-sectional area at the middle height position (i.e., the middle position of the blade) to the cross-sectional area of ​​the blade tip 100 is between 1.0 and 1.1. Based on the limitation of the cross-sectional area, at the overall height of the rotor blade 10, the cross-section (i.e., the blade profile) of the rotor blade 10 changes very little, which is beneficial to the design of the above-mentioned cooling structure. In some examples, the above-mentioned rotor blade 10 is a hollow cooling blade. Correspondingly, the above-mentioned cooling structure adopts a combination design of multi-path convection design, impact and air film, and sprinkler head air film cooling. At the same time, the slit 108 of the trailing edge 103 adopts a semi-slit 108 design to improve the cooling effect.

[0034] Figure 5 Where γ represents the installation angle of the rotor blade 10 at the cross-sectional position, and the installation angle γ is the angle between the chord line and the θ axis direction; in some embodiments, the absolute value of the difference in the installation angles of all cross sections of the above-mentioned rotor blade 10 at the overall height is less than 10°. Exemplarily, at the overall height of the rotor blade 10, the installation angles of all cross sections of the rotor blade 10 are between 50° and 60°. Based on the limitation of the installation angle, the rotor blade 10 can be made straighter as a whole, which is also beneficial to the design of the above-mentioned complex cooling structure, for example, and can reduce the turning angle of the airflow when it flows through the rotor blade, so as to reduce the lateral pressure on the rotor blade, so as to reduce the secondary flow loss. Furthermore, the number of blades of the above-mentioned rotor blade 10 is 40 to 45. Based on the limitation of the installation angle and the number of rotor blades 10, that is, on the basis of a smaller number of rotor blades 10, the size of the installation angle is reduced at the same time, so that the tenon 104 can cover the blade root 101 without increasing the broaching angle of the tenon 104 (see Figure 4a ), even if the tenon 104 can be arranged reasonably and the processing difficulty of the tenon 104 is reduced, a smaller number of rotor blades 10 can reduce the weight of the engine and reduce the manufacturing cost of the engine.

[0035] Furthermore, the cross-sectional radius of the rotor blade 10 is 110-140 mm, and the blade channel height is 27-30 mm. Based on the limitation of the cross-sectional radius and the channel height of the rotor blade 10, that is, the rotor blade 10 adopts a design with a small cross-sectional radius and a short blade channel height, which can improve the turbine load factor (for example, 1.75-1.80), the flow coefficient (for example, 0.75-0.80) and the reaction force (for example, 0.65-0.70). At the same time, the grating s (see Figure 5 ) is 17-22 mm, and the blade lift coefficient of the cross section of the rotor blade 10 is 0.8-1.0, wherein the height, pitch and blade lift coefficient of the rotor blade 10 are designed to be compatible with the above-mentioned number of rotor blades 10 and installation angle parameters. Based on the limitations of parameters such as the height, pitch and blade lift coefficient of the rotor blade 10, the installation angle of the rotor blade 10 can be reduced while reducing the number of rotor blades 10, and the tenon 104 can cover the cross section of the blade root 101 without increasing the chamfering angle of the tenon 104.

[0036] Based on the above-mentioned parameter definition of the cross section (i.e., blade shape) of the rotor blade 10, i.e., the number of rotor blades 10 and the installation angle definition of the cross section of the rotor blade 10 at a height position, the overall configuration of the rotor blade 10 is straight, which facilitates the design of the complex cooling structure. At the same time, by defining the cross section chord length of the rotor blade 10 at a height position, the tip aerodynamic load level can be reduced, the lateral pressure gradient can be reduced, and the load distribution of the turbine rotor blade 10 under high load factor and high flow capacity can be uniform, the aerodynamic parameters of the blade surface can be reasonably distributed, the flow field can be uniform, and the secondary flow can be reduced (see Figure 6a and Figure 6b Comparison of the secondary flow area in Figure 6a 6a is a schematic diagram of the secondary flow area of ​​the turbine blade in the prior art, and 6b is a schematic diagram of the secondary flow area of ​​the rotor blade in the present application. The part marked with the ellipse in the figure is the secondary flow area, and the area in the middle is the mainstream area). The aerodynamic loss is small and the turbine efficiency is high; the cooling effect is good, the blade casting processability is good, the blade strength reserve is high, and the service life is long.

[0037] Compared to the embodiments shown in the drawings, feasible implementations within the scope of the present disclosure may have fewer components, other components not shown in the drawings, different components, differently arranged components, or differently connected components, etc. In addition, two or more components in the drawings may be implemented in a single component, or a single component shown in the drawings may be implemented as multiple separate components.

[0038] Unless otherwise defined, the technical terms or scientific terms used herein shall have the usual meanings understood by persons of ordinary skill in the field to which the present disclosure belongs. The words "first", "second" and similar words used in the patent application specification and claims of the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "one" or "one" do not necessarily indicate a quantity restriction. Words such as "include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Words such as "connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

Claims

1. A cooling turbine rotor blade, characterized in that: The rotor blade (10) is installed in the tenon groove (111) of the turbine disk (110) through the tenon (104), the rotor blade is provided with a cooling structure, the installation angle of the cross section of the rotor blade (10) at any height position is 50-60 degrees, and the number of the rotor blades is 40-45.

2. A cooling turbine rotor blade according to claim 1, characterized in that: The cross-sectional radius of the rotor blade (10) is 110-140 mm.

3. A cooling turbine rotor blade according to claim 1 or 2, characterized in that: The chord length of the cross section of the rotor blade (10) at any height position is 25-27 mm.

4. A cooling turbine rotor blade according to claim 3, characterized in that: The rotor blade (10) has a blade tip portion (100) and a blade root portion (101) in a radial direction, and the cross-sectional chord length of the blade tip portion (100) is greater than the cross-sectional chord length of the blade root portion (101).

5. A cooling turbine rotor blade according to claim 1, characterized in that: The pitch of the rotor blades (10) is 17-22 mm.

6. A cooling turbine rotor blade according to claim 1, characterized in that: The inlet structural angle of the cross section of the rotor blade (10) at any height position is 50-80 degrees, and the outlet structural angle is 30-40 degrees.

7. A cooling turbine rotor blade according to claim 6, characterized in that: The rotor blade (10) has a blade tip portion (100) and a blade root portion (101) in the radial direction, and an outlet configuration angle of a cross section of the blade tip portion (100) is greater than an outlet configuration angle of a cross section of the blade root portion (101).

8. The method for cooling turbine rotor blades according to claim 1, characterized in that: The rotor blade (10) has a blade tip (100) and a blade root (101) in the radial direction, the maximum thickness of the blade tip (100) cross section is 4.5 to 5 mm, and the ratio of the cross section area of ​​the blade root (101) to the cross section area of ​​the blade tip (100) is 1.2 to 1.

3.

9. A cooling turbine rotor blade according to claim 1, characterized in that: The rotor blade (10) has a blade tip portion (100) and a blade root portion (101) in the radial direction, and has a leading edge portion (102) and a trailing edge portion (103) in the axial direction. The cooling structure comprises a groove (106) and a cooling hole (107) formed at the blade tip portion (100), a slit (108) formed at the trailing edge portion (103), and a channel formed in the rotor blade (10) for connecting the cooling hole (107) and the slit (108).

10. A cooling turbine rotor blade according to claim 9, characterized in that: The split seam (108) is a half split seam structure.

Images