Combined ceramic matrix composite double-wall high-pressure turbine rotor blade

Abstract

The present invention provides a combined ceramic matrix composite double-layer wall high-pressure turbine rotor blade, comprising: a metal load-bearing matrix, on the outer wall of which there are provided a plurality of dovetail grooves, and each dovetail groove extends along the radial direction of the metal load-bearing matrix; a plurality of ceramic matrix heat insulation shells, on the inner side of each ceramic matrix heat insulation shell there is provided a dovetail tenon, and the dovetail tenons of the plurality of ceramic matrix heat insulation shells are in one-to-one plug-in fit with the plurality of dovetail grooves of the metal load-bearing matrix. By providing a plurality of ceramic matrix heat insulation shells on the outer side of the metal load-bearing matrix, the embodiment of the present invention can have both the excellent temperature resistance of the ceramic matrix composite blade and the excellent mechanical properties of the superalloy blade, can withstand a large mechanical load, has a light weight, and has strong processability.

Description

Technical Field

[0001] This specification relates to the technical field of aeroengines, and particularly relates to a combined ceramic matrix composite double-wall high-pressure turbine rotor blade. Background Art

[0002] As an important part of the turbine component of an aeroengine, the high-pressure turbine rotor blade plays a key role in converting the thermal energy of the gas into mechanical energy. It not only has a very high working temperature but also needs to bear a large mechanical load. With the continuous improvement of the performance requirements of aeroengines, the temperature before the turbine gradually increases. Under the existing cooling technology conditions, the traditional superalloy material blades can no longer meet the growing temperature resistance requirements. Ceramic matrix composite blades with more excellent temperature resistance and smaller density are the current research hotspots. They can not only effectively improve the temperature resistance level of the blades but also significantly reduce the weight of the blades themselves, thus helping to improve the thrust-to-weight ratio of aeroengines. However, there are great deficiencies in the mechanical properties of ceramic matrix composite blades, which cannot bear large mechanical loads, and limited by the process level, it is difficult to manufacture the complex cavity structure of the blades. Summary of the Invention

[0003] In view of this, the embodiments of this specification provide a combined ceramic matrix composite double-wall high-pressure turbine rotor blade to achieve the purpose of being able to bear a greater mechanical load.

[0004] The technical solution of the embodiment of the present invention is: A combined ceramic matrix composite double-wall high-pressure turbine rotor blade, including: a metal load-bearing matrix, on the outer wall of which there are multiple dovetail grooves, and each dovetail groove extends along the radial direction of the metal load-bearing matrix; a plurality of ceramic matrix heat insulation shells, on the inner side of each ceramic matrix heat insulation shell there is a dovetail tenon, and the dovetail tenons of the plurality of ceramic matrix heat insulation shells are in one-to-one insertion fit with the multiple dovetail grooves of the metal load-bearing matrix.

[0005] Further, except that both ends of the ceramic matrix heat insulation shell located outside the leading edge of the metal load-bearing matrix are lap joints, both ends of each of the remaining ceramic matrix heat insulation shells are a positioning boss and a lap joint respectively. Each positioning boss abuts against the outer wall of the metal load-bearing matrix. The two adjacent and connected ceramic matrix heat insulation shells are connected by the corresponding positioning boss and the corresponding lap joint, and an expansion gap is provided between the corresponding positioning boss and the corresponding lap joint.

[0006] Further, there is a gap between the lap joints of the ceramic matrix heat insulation shells located on both sides of the trailing edge of the metal load-bearing matrix.

[0007] Further, on the inner side of the ceramic matrix heat insulation shells located on both sides of the trailing edge of the metal load-bearing matrix, there are support bosses, and each support boss abuts against the outer wall of the metal load-bearing matrix.

[0008] Furthermore, the dovetail tenons and support bosses of the ceramic matrix thermal insulation shells located at the trailing edge of the metal load-bearing matrix and on the suction side are both discontinuously distributed.

[0009] Furthermore, the inner wall of each ceramic matrix thermal insulation shell and the outer wall of the metal load-bearing matrix are spaced apart and form an impact chamber for the passage of cooling gas.

[0010] Furthermore, the metal load-bearing matrix is provided with a plurality of impact holes distributed at intervals, and the plurality of impact holes distributed at intervals correspond to the positions of the corresponding impact chambers.

[0011] Furthermore, except for the ceramic matrix thermal insulation shells located at the trailing edge of the metal load-bearing matrix and on the suction side, a plurality of film holes are provided on the remaining ceramic matrix thermal insulation shells, and the plurality of film holes correspond to the positions of the corresponding impact chambers.

[0012] Furthermore, an expansion gap is provided between each dovetail groove and the corresponding dovetail tenon.

[0013] Furthermore, the metal load-bearing matrix is provided with a positioning platform, and the lower ends of the plurality of ceramic matrix thermal insulation shells are all in contact with the upper surface of the positioning platform.

[0014] Furthermore, the combined ceramic matrix composite double-wall high-pressure turbine rotor blade further includes a cover plate, which is fixedly arranged at the upper end of the metal load-bearing matrix and is in contact with the upper end of each ceramic matrix thermal insulation shell.

[0015] Furthermore, a stepped surface is provided on the inner side of the upper end of each ceramic matrix thermal insulation shell, and the stepped surfaces of the plurality of ceramic matrix thermal insulation shells together form an installation space for accommodating the cover plate.

[0016] Compared with the prior art, the at least one technical solution adopted in the embodiments of the present specification can achieve at least the following beneficial effects: By arranging a plurality of ceramic matrix thermal insulation shells on the outer side of the metal load-bearing matrix, the embodiments of the present invention can combine the excellent temperature resistance of the ceramic matrix composite material blade and the excellent mechanical properties of the superalloy blade, can withstand large mechanical loads, are lighter in weight, and have strong processability. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0018] Figure 1 is an exploded schematic view of an embodiment of the present invention;

[0019] Figure 2 is the assembly schematic diagram of the embodiment of the present invention;

[0020] Figure 3 is Figure 2 the A-A sectional view;

[0021] Figure 4 is Figure 3 the B-B sectional view;

[0022] Figure 5 is Figure 3 the C-C sectional view;

[0023] Reference numerals in the figure: 1, metal load-bearing matrix; 101, leading edge; 102, partition; 103, dovetail groove; 104, inner wall; 105, impact hole; 106, tail split seam of inner wall; 107, positioning platform; 108, flange; 109, sealing groove; 110, fir tree tenon; 111, top plate; 112, first dust removal hole; 113, cold air cavity; 114, impact cavity; 115, air collecting cavity; 116, trailing edge;

[0024] 2, ceramic matrix thermal insulation shell; 201, outer wall; 202, positioning boss; 203, dovetail tenon; 204, film hole; 205, support boss; 206, tail split seam of outer wall; 207, step surface;

[0025] 3, cover plate; 301, second dust removal hole. Specific embodiments

[0026] The embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0027] The following illustrates the implementation manners of the present application through specific specific examples. Those skilled in the art can easily understand other advantages and effects of the present application from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The present application can also be implemented or applied through other different specific implementation manners. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that, without conflict, the following embodiments and the features in the embodiments can be combined with each other. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without making creative efforts belong to the scope of protection of the present application.

[0028] Such as Figures 1 to 5As shown in the figure, an embodiment of the present invention provides a combined ceramic matrix composite double-wall high-pressure turbine rotor blade, which includes a metal load-bearing matrix 1 and a plurality of ceramic matrix heat insulation shells 2. A plurality of dovetail grooves 103 are provided on the outer wall of the metal load-bearing matrix 1, and each dovetail groove 103 extends along the radial direction of the metal load-bearing matrix 1; a dovetail tenon 203 is provided on the inner side of each ceramic matrix heat insulation shell 2, and the dovetail tenons 203 of the plurality of ceramic matrix heat insulation shells 2 are inserted and matched with the plurality of dovetail grooves 103 of the load-bearing matrix 1 one by one.

[0029] By arranging a plurality of ceramic matrix heat insulation shells 2 on the outer side of the metal load-bearing matrix 1, the embodiment of the present invention can have both the excellent temperature resistance of the ceramic matrix composite blade and the excellent mechanical properties of the superalloy blade, can withstand a large mechanical load, has a light weight, and has strong processability.

[0030] The metal load-bearing matrix 1 is precision cast from a superalloy material and is mainly used to bear the mechanical load of the blade. The ceramic matrix heat insulation shell 2 is woven from a ceramic matrix composite material and wraps the metal load-bearing matrix 1, and is mainly used to block the heat of the high-temperature gas.

[0031] The inner wall 104 of the blade is divided into several cold air cavities 113 by the partition plate 102. Dovetail grooves 103 are provided at both ends and the leading edge 101 of the partition plate 102, and corresponding dovetail tenons 203 are provided on the ceramic matrix heat insulation shell 2. The inner wall 104 and the outer wall 201 of the blade are connected by the dovetail groove 103 and the dovetail tenon 203. The positioning boss 202 and the supporting boss 205 of the ceramic matrix heat insulation shell 2 are abutted against the outer surface of the metal load-bearing matrix 1 to enhance the structural stability, and together with the dovetail tenon 203, divide the space between the inner wall 104 and the outer wall 201 into a plurality of impact cavities 114. Among them, the thickness of the inner wall 104 is generally 1-2 mm, the thickness of the outer wall 201 is not less than 1 mm, the thinnest part of the dovetail tenon 203 is not less than 1 mm, and the contact width between the positioning boss 202, the supporting boss 205 and the outer surface of the metal load-bearing matrix 1 is not less than 1.5 mm.

[0032] It should be noted that an expansion gap not greater than 0.5 mm is provided between each dovetail groove 103 and the corresponding dovetail tenon 203.

[0033] The ceramic matrix thermal insulation shells 2 are connected by overlapping the outer wall 201 on the positioning bosses 202 of adjacent ceramic matrix thermal insulation shells 2. The contact width of the overlapping joint along the blade profile direction is not less than 1 mm, and an expansion gap not greater than 0.3 mm is left at the joint along the blade profile direction. The two adjacent ceramic matrix thermal insulation shells 2 on both sides of the trailing edge 116 of the metal load-bearing matrix 1 are not overlapped, and a gap of 0.5 - 1 mm is left between them to form the outer wall trailing split 206. The inner wall 104 forms the inner wall trailing split 106 by arranging a plurality of discontinuous rectangular windows near the trailing edge 116, and the window width is generally 0.5 - 1 mm.

[0034] The metal load-bearing matrix 1 is provided with a positioning platform 107, and the lower end surface of the ceramic matrix thermal insulation shell 2 is in contact and cooperation with the upper surface of the positioning platform 107 of the metal load-bearing matrix 1. The upper end of the ceramic matrix thermal insulation shell 2 is provided with a stepped surface 207, and the lower surface of the cover plate 3 is in contact and cooperation with the upper surface of the stepped surface 207. The radial fixation of the ceramic matrix thermal insulation shell 2 is realized through the positioning platform 107 and the cover plate 3.

[0035] It should be noted that the cover plate 3 is connected to the upper surface of the top plate 111 of the metal load-bearing matrix 1 by brazing, which is mainly used to realize the radial positioning of the ceramic matrix thermal insulation shell 2. To improve the welding performance and strength, the material of the cover plate 3 is the same superalloy as that of the metal load-bearing matrix 1, and the thicknesses of the top plate 111 and the cover plate 3 are generally 1 - 1.5 mm.

[0036] The inner wall 104 of the blade is provided with impact holes 105. A plurality of impact holes 105 distributed at intervals correspond to the positions of the corresponding impact chambers 114. The diameter of the impact holes 105 is generally 0.5 - 1 mm. The outer wall 201 is provided with film holes 204, and the diameter of the film holes 204 is generally 0.3 - 0.5 mm. The cold air of the blade enters the cold air chamber 113 from the bottom of the fir-tree tenon 110, conducts convective cooling on the inner surface of the inner wall 104, then flows through the impact holes 105 to conduct impact cooling on the outer wall 201. At the same time, the cold air flows in the impact chamber 114 to conduct convective cooling on the outer surface of the inner wall 104 and the inner surface of the outer wall 201, and then flows through the film holes 204 and is discharged to realize the film covering cooling of the outer surface of the outer wall 201.

[0037] Since there are generally shock waves on the outer surface of the suction side near the trailing edge region of the turbine blade, the cooling air flowing out of the film holes 204 of the blade is extremely likely to cause relatively large mixing losses to the main gas flow. Therefore, film holes 204 are not provided on the outer layer wall 201 near the trailing edge region of the suction side. Instead, the dovetail tenons 203 and support bosses 205 of the ceramic matrix heat insulation shell 2 at this location are set as discontinuous blocks. The cooling air flowing out of the impact holes 105 near the trailing edge region flows through the opening grooves formed between adjacent blocks to the gas collecting cavity 115 in the trailing edge region of the blade, converges with the cooling air flowing out of the trailing split seam 106 of the inner layer wall, and then is discharged together from the trailing split seam 206 of the outer layer wall to achieve cooling of the trailing edge region of the blade.

[0038] The metal load-bearing matrix 1 and the cover plate 3 are respectively provided with first dust removal holes 112 and second dust removal holes 301 for each cooling air cavity 113. The positions of the first dust removal holes 112 and the second dust removal holes 301 correspond one by one and have the same diameter, generally 0.5 - 1 mm, for discharging impurities such as dust that may exist in the inner cavity of the blade. The metal load-bearing matrix 1 is provided with a flange 108 for forming a downstream channel surface during the assembly of the entire ring of blades. The radial height of the flange 108 must be lower than the radial height of the positioning platform 107. The metal load-bearing matrix 1 is provided with a sealing groove 109 for installing sealing pieces for gas sealing, and the provided fir tree tenons 110 are used to achieve the connection between the blade and the turbine disk. The number of teeth of the fir tree tenons 110 can be selected as needed, generally 2 teeth or 3 teeth.

[0039] The embodiments of the present invention have the following technical effects:

[0040] 1. Compared with a single nickel-based superalloy material blade, this structure effectively increases the temperature resistance level by more than 200 °C;

[0041] 2. Compared with a single ceramic matrix composite material blade, the mechanical properties of this structure are greatly improved;

[0042] 3. Compared with a double-layer wall nickel-based superalloy integral casting blade, this structure reduces the weight by more than 20%;

[0043] 4. The blade structure is reliable, and the parts of the ceramic matrix composite material have a simple structure and strong manufacturability.

[0044] The above is only the specific implementation manner of this application, but the protection scope of this application is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed in this application should be covered within the protection scope of this application. Therefore, the protection scope of this application should be subject to the protection scope of the claims.

Claims

1. A combined ceramic matrix composite double - wall high - pressure turbine rotor blade, characterized in that, Comprising: A metal load-bearing matrix (1), on the outer wall of which there are a plurality of dovetail grooves (103), and each dovetail groove (103) extends along the radial direction of the metal load-bearing matrix (1); A plurality of ceramic matrix heat insulation shells (2), on the inner side of each ceramic matrix heat insulation shell (2) there is a dovetail tenon (203), and the dovetail tenons (203) of the plurality of ceramic matrix heat insulation shells (2) are inserted and matched with the plurality of dovetail grooves (103) of the metal load-bearing matrix (1) one by one; Except that both ends of the ceramic matrix heat insulation shell (2) located outside the leading edge (101) of the metal load-bearing matrix (1) are lap joints, both ends of each of the remaining ceramic matrix heat insulation shells (2) are respectively a positioning boss (202) and a lap joint, each positioning boss (202) abuts against the outer wall of the metal load-bearing matrix (1), and two adjacent and connected ceramic matrix heat insulation shells (2) are connected by the corresponding positioning boss (202) and the corresponding lap joint, and an expansion gap is provided between the corresponding positioning boss (202) and the corresponding lap joint; An expansion gap is provided between each dovetail groove (103) and the corresponding dovetail tenon (203).

2. The combined ceramic matrix composite double - wall high - pressure turbine rotor blade according to claim 1, characterized in that, A gap is provided between the lap joints of the ceramic matrix heat insulation shells (2) located on both sides of the trailing edge (116) of the metal load-bearing matrix (1).

3. The combined ceramic matrix composite double - wall high - pressure turbine rotor blade according to claim 1, characterized in that, On the inner sides of the ceramic matrix heat insulation shells (2) located on both sides of the trailing edge (116) of the metal load-bearing matrix (1), there are support bosses (205), and each support boss (205) abuts against the outer wall of the metal load-bearing matrix (1).

4. The combined ceramic matrix composite double - wall high - pressure turbine rotor blade according to claim 3, characterized in that, The dovetail tenons (203) and the support bosses (205) of the ceramic matrix heat insulation shell (2) located at the trailing edge (116) of the metal load-bearing matrix (1) and on the suction side are both discontinuously distributed.

5. The combined ceramic matrix composite double - wall high - pressure turbine rotor blade according to claim 1, characterized in that, The inner wall of each ceramic matrix heat insulation shell (2) and the outer wall of the metal load-bearing matrix (1) are spaced apart and form an impact cavity (114) for the cooling gas to pass through.

6. The combined ceramic matrix composite double - wall high - pressure turbine rotor blade according to claim 5, characterized in that, The metal load-bearing matrix (1) is provided with a plurality of impact holes (105) distributed at intervals, and the plurality of impact holes (105) distributed at intervals correspond to the positions of the corresponding impact cavities (114).

7. The combined ceramic matrix composite double - wall high - pressure turbine rotor blade according to claim 6, characterized in that, Except for the ceramic matrix heat insulation shell (2) located at the trailing edge (116) of the metal load-bearing matrix (1) and on the suction side, a plurality of film holes (204) are provided on each of the remaining ceramic matrix heat insulation shells (2), and the plurality of film holes (204) correspond to the positions of the corresponding impact cavities (114).

8. The combined ceramic matrix composite double - wall high - pressure turbine rotor blade according to claim 1, characterized in that, The metal load-bearing matrix (1) is provided with a positioning platform (107), and the lower ends of the plurality of ceramic matrix heat insulation shells (2) all abut against the upper surface of the positioning platform (107).

9. The combined ceramic matrix composite double - wall high - pressure turbine rotor blade according to claim 1, characterized in that, The combined ceramic matrix composite double-layer wall high-pressure turbine rotor blade further includes a cover plate (3), which is fixedly arranged at the upper end of the metal load-bearing matrix (1) and abuts against the upper end of each ceramic matrix heat insulation shell (2).

10. The combined ceramic matrix composite double - wall high - pressure turbine rotor blade according to claim 9, characterized in that, On the inner side of the upper end of each ceramic matrix heat insulation shell (2), there is a step surface (207), and the step surfaces (207) of the plurality of ceramic matrix heat insulation shells (2) together form an installation space for accommodating the cover plate (3).

Images