High-speed axial-flow type distributed bearing ceramic turbine rotor structure

Abstract

The invention relates to a high-speed axial-flow type distributed bearing ceramic turbine rotor structure. The axial flow turbine rotor structure comprises an integral axial flow bladed disc, a turbine shaft, a distributed bearing cover, a bolt and a locking nut. The integral axial flow bladed disc is of a blade and wheel disc integrated structure, distributed force bearing positioning bosses are evenly distributed on the end faces of the two sides of the wheel disc of the bladed disc in the circumferential direction, and through holes assembled with bolts are formed in the centers of the distributed force bearing positioning bosses. A flange plate is arranged at one end of the turbine shaft, distributed bearing positioning counter bores are evenly distributed in the end face of one side of the flange plate, and through holes are formed in the bottoms of the distributed bearing positioning counter bores. Distributed force bearing positioning counter bores are evenly distributed in one side end of the distributed force bearing cover, and through holes are formed in the bottoms of the distributed force bearing positioning counter bores. Threaded locking of the integral axial-flow bladed disc, the turbine shaft and the distributed bearing cover assembly structure is achieved through bolts and locking nuts, and a high-speed axial-flow distributed bearing ceramic turbine rotor structure is formed. The turbine rotor structure has the characteristics of high reliability, good manufacturability and the like.

Description

Technical Field

[0001] The invention belongs to the field of turbine engine turbine rotor structure design, and in particular relates to a high-speed axial flow distributed load-bearing ceramic turbine rotor structure. Background Art

[0002] Small turbine engines are one of the main power forms for small aircraft such as drones and target drones. The engine converts fuel thermal energy into shaft work or thrust through processes such as compressor air compression, combustion chamber heating, turbine expansion, and nozzle discharge, thereby meeting the thrust requirements of small aircraft.

[0003] The axial-flow turbine rotor is one of the key components of a turbine engine. It is subjected to multiple loads such as mechanical loads, aerodynamic loads, and thermal loads during operation. The working loads and environment are harsh. It is one of the main components that affect the performance and structural reliability of the turbine engine, and it is also a key component that restricts the life of the turbine engine. Therefore, a reasonable design of the turbine rotor structure is of great significance to improving the performance and reliability of the engine.

[0004] In order to improve the thrust-to-weight ratio and other performance of turbine engines, increasing the operating temperature of the turbine and reducing the weight of the engine components are one of the effective technical approaches. For example, the turbine blades in the axial-flow turbine rotor can be made of ceramic materials, which can increase the operating temperature of the turbine rotor on the one hand, and reduce the weight of the turbine rotor on the other hand, thereby achieving the purpose of lightweighting. For traditional high-temperature alloy turbine blades, the integration of the axial-flow turbine blades and the turbine shaft can be achieved by welding, but for turbine impellers made of ceramic materials, it is impossible to achieve the connection between the turbine blades and the turbine shaft by welding or other methods. To this end, it is necessary to solve the problem of the integration of the ceramic turbine blades with the turbine shaft to ensure the reliability of the axial-flow turbine rotor.

[0005] In response to the high performance and lightweight requirements of the axial-flow turbine rotor of a small turbine engine, the connection method of the axial-flow turbine blade disk and the turbine shaft is reasonably designed to achieve integration of the axial-flow turbine blade disk and the turbine shaft. At the same time, the stress distribution of the turbine rotor structure is optimized, and the structural reliability of the turbine rotor is improved. This ensures the service life of the engine while improving the performance of the small turbine engine. Summary of the invention

[0006] The present invention is aimed at the turbine rotor structure of a high-performance small turbine engine, and proposes a high-speed axial flow distributed load-bearing ceramic turbine rotor structure. The axial flow turbine rotor structure includes an integral axial flow blade disk, a turbine shaft, a distributed load-bearing cover, bolts and locking nuts. The integral axial flow blade disk is an integrated structure of blades and a wheel disk. The end surfaces of both sides of the wheel disk of the blade disk are evenly distributed with distributed load-bearing positioning bosses along the circumferential direction, and the center of the distributed load-bearing positioning bosses has a through hole assembled with the bolts. A flange is provided at one end of the turbine shaft, and the end surface of one side of the flange is evenly distributed with distributed load-bearing positioning countersunk holes, and the bottom of the distributed load-bearing positioning countersunk holes has a through hole. One side end of the distributed load-bearing cover is evenly distributed with distributed load-bearing positioning countersunk holes, and the bottom of the distributed load-bearing positioning countersunk holes has a through hole. The threaded locking of the assembly structure of the integral axial flow blade disk, the turbine shaft and the distributed load-bearing cover is achieved by bolts and locking nuts to form a lightweight distributed load-bearing axial flow turbine rotor structure.

[0007] The technical solution of the present invention:

[0008] A high-speed axial flow distributed load-bearing ceramic turbine rotor structure comprises an integral axial flow blade disk, a turbine shaft, a distributed load-bearing cover, bolts and locking nuts.

[0009] The integral axial flow blade disk is an integrated structure of blades and discs. The integral axial flow blade disk is made of homogeneous silicon nitride ceramic material. The end surfaces on both sides of the disc of the integral axial flow blade disk are uniformly distributed along the circumferential direction with distributed load-bearing positioning bosses assembled with the turbine shaft and the distributed load-bearing cover. The central part of the distributed load-bearing positioning boss of the integral axial flow blade disk is provided with a through hole assembled with a bolt. The distributed load-bearing positioning bosses on the end surfaces on both sides of the disc of the integral axial flow blade disk are respectively fitted with the distributed load-bearing positioning countersunk holes of the distributed load-bearing cover and the distributed load-bearing positioning countersunk holes on the flange side of the turbine shaft by interference fitting.

[0010] The turbine shaft has a flange at one end connected to the integral axial flow blade disk, and one end surface of the turbine shaft flange is uniformly provided with distributed load-bearing positioning countersunk holes assembled with the distributed load-bearing positioning bosses of the integral axial flow blade disk along the circumferential direction, and the bottom of the distributed load-bearing positioning countersunk holes of the turbine shaft has through holes assembled with bolts. Interference fitting is adopted between the distributed load-bearing positioning countersunk holes on one side of the turbine shaft flange and the distributed load-bearing positioning bosses on the end surface of the wheel disk of the integral axial flow blade disk.

[0011] One side end surface of the distributed load-bearing cover is evenly distributed along the circumferential direction with distributed load-bearing positioning countersunk holes assembled with the distributed load-bearing positioning bosses of the integral axial flow blade disk. The bottom of the distributed load-bearing positioning countersunk holes of the distributed load-bearing cover has through holes assembled with bolts. The distributed load-bearing positioning countersunk holes of the distributed load-bearing cover and the distributed load-bearing positioning bosses on the end surface of the wheel of the integral axial flow blade disk are fitted with interference fit.

[0012] The bolt includes a head, a polished rod and a stud. The head of the bolt is a hexagonal cylindrical structure. The bolt is assembled with the through hole of the turbine shaft, the through hole of the integral axial flow blade disk and the through hole of the distributed load-bearing cover. The external threaded part of the bolt is assembled with the locking nut.

[0013] The locking nut is a threaded blind hole structure, the locking nut is installed on the bolt, and one side of the locking nut is pressed against one side end surface of the distributed load-bearing cover.

[0014] The integral axial flow blade disk is assembled with the turbine shaft through a distributed load-bearing positioning boss and a distributed load-bearing positioning countersunk hole. The integral axial flow blade disk is assembled with the distributed load-bearing cover through a distributed load-bearing positioning boss and a distributed load-bearing positioning countersunk hole. The assembly structure of the integral axial flow blade disk, the turbine shaft and the distributed load-bearing cover is threadedly locked by bolts and locking nuts to form a high-speed axial flow distributed load-bearing ceramic turbine rotor structure.

[0015] The beneficial effects of the present invention are:

[0016] The present invention proposes a high-speed axial flow distributed load-bearing ceramic turbine rotor structure. The integral axial flow blade disc adopts homogeneous silicon nitride ceramic material, which can not only improve the working temperature of the turbine rotor, but also effectively reduce the weight of the blade disc, so as to achieve the purpose of lightweight. The end faces of the wheel disc on both sides of the integral axial flow blade disc are evenly distributed with distributed load-bearing positioning bosses along the circumferential direction. On the one hand, the turbine rotor can be well positioned with the integral axial flow blade disc assembly structure. On the other hand, the centrifugal load and torque transmitted by the blade disc during operation can be dispersed and transmitted to the turbine shaft, so as to reduce the working stress of the blade disc and improve the reliability of the turbine rotor structure. One end of the turbine shaft is provided with a flange and the flange is provided with distributed load-bearing positioning countersunk holes, so as to not only achieve good positioning of the turbine shaft with the integral axial flow blade disc, but also achieve distributed transmission of load and its uniformity, so as to ensure the structural reliability of the turbine rotor. One side of the distributed load-bearing cover is provided with distributed load-bearing positioning countersunk holes, so as to achieve effective positioning of both sides of the integral axial flow blade disc and uniformity of load transmission, so as to ensure the reliability of the turbine rotor during high-speed rotation. The use of bolts and locking nuts can not only achieve the locking of the integral axial flow blade disk with the turbine shaft and the distributed load-bearing cover assembly structure, but also facilitate the assembly and disassembly of the axial flow turbine rotor structure, so that the turbine rotor has good processability and meets the maintainability requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the structure of a high-speed axial-flow distributed load-bearing ceramic turbine rotor.

[0018] Figure 2 It is a schematic diagram of the overall axial flow blade disk structure.

[0019] Figure 3 It is a schematic diagram of the turbine shaft structure.

[0020] Figure 4 It is a schematic diagram of the distributed load-bearing cover structure.

[0021] 1Integral axial flow blade 2Turbine shaft 3Distributed bearing cover 4Bolt

[0022] 5 Locking nut 6 Distributed load-bearing positioning boss of the integral axial flow blade

[0023] 7Through hole of integral axial flow blade disk 8Flange of turbine shaft

[0024] 9 Distributed load bearing positioning countersunk hole of turbine shaft 10 Through hole of turbine shaft

[0025] 11 Distributed load-bearing positioning countersunk holes of distributed load-bearing cover 12 Through holes of distributed load-bearing cover DETAILED DESCRIPTION

[0026] A high-speed axial flow distributed load-bearing ceramic turbine rotor structure comprises an integral axial flow blade disk 1, a turbine shaft 2, a distributed load-bearing cover 3, bolts 4 and locking nuts 5.

[0027] The integral axial flow blade disk 1 is an integrated structure of blades and discs. The integral axial flow blade disk 1 is made of homogeneous silicon nitride ceramic material. The end surfaces on both sides of the disc of the integral axial flow blade disk 1 are uniformly distributed along the circumferential direction with distributed load-bearing positioning bosses 6 assembled with the turbine shaft 2 and the distributed load-bearing cover 3. The central part of the distributed load-bearing positioning boss 6 of the integral axial flow blade disk 1 has a through hole 7 assembled with the bolt 4. The distributed load-bearing positioning bosses 6 on the end surfaces on both sides of the disc of the integral axial flow blade disk 1 are respectively fitted with the distributed load-bearing positioning countersunk holes 11 of the distributed load-bearing cover 3 and the distributed load-bearing positioning countersunk holes 9 on the flange side of the turbine shaft 2 by interference fitting.

[0028] The turbine shaft 2 has a flange 8 at one end connected to the integral axial flow blade disk 1. One end face of the flange 8 of the turbine shaft 2 has distributed load-bearing positioning countersunk holes 9 uniformly distributed along the circumferential direction for assembly with the distributed load-bearing positioning bosses 6 of the integral axial flow blade disk 1. The bottom of the distributed load-bearing positioning countersunk holes 9 of the turbine shaft 2 has through holes 10 for assembly with the bolts 4. The distributed load-bearing positioning countersunk holes 9 on one side of the flange of the turbine shaft 2 and the distributed load-bearing positioning bosses 6 on the end face of the wheel disk of the integral axial flow blade disk 1 are fitted by interference fit.

[0029] One side end face of the distributed load-bearing cover 3 is uniformly distributed along the circumferential direction with distributed load-bearing positioning countersunk holes 11 assembled with the distributed load-bearing positioning bosses 6 of the integral axial flow blade disk 1. The bottom of the distributed load-bearing positioning countersunk holes 11 of the distributed load-bearing cover 3 has through holes 12 assembled with the bolts 4. The distributed load-bearing positioning countersunk holes 11 of the distributed load-bearing cover 3 and the distributed load-bearing positioning bosses 6 on the end face of the wheel of the integral axial flow blade disk 1 are fitted by interference fit.

[0030] The bolt 4 includes a head, a bare rod and a stud. The head of the bolt 4 is a hexagonal cylindrical structure. The bolt 4 is assembled with the through hole 10 of the turbine shaft 2, the through hole 7 of the integral axial flow blade disk 1 and the through hole 12 of the distributed load-bearing cover 3. The external threaded portion of the bolt 4 is assembled with the locking nut 5.

[0031] The locking nut 5 is a threaded blind hole structure, and the locking nut 5 is installed on the bolt 4 . One side of the locking nut 5 is pressed against the end surface of one side of the distributed load-bearing cover 3 .

[0032] The integral axial flow blade disk 1 is assembled with the turbine shaft 2 through the distributed load-bearing positioning boss 6 and the distributed load-bearing positioning countersunk hole 9. The integral axial flow blade disk 1 is assembled with the distributed load-bearing cover 3 through the distributed load-bearing positioning boss 6 and the distributed load-bearing positioning countersunk hole 11. The assembly structure of the integral axial flow blade disk 1, the turbine shaft 2 and the distributed load-bearing cover 3 is threadedly locked by bolts 4 and locking nuts 5 to form a high-speed axial flow distributed load-bearing ceramic turbine rotor structure.

[0033] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A high-speed axial flow distributed load-bearing ceramic turbine rotor structure, characterized in that: It comprises an integral axial flow blade disk (1), a turbine shaft (2), a distributed load-bearing cover (3), bolts (4) and a locking nut (5); The integral axial flow blade disk (1) is an integrated structure of blades and a wheel disk. The integral axial flow blade disk (1) is made of homogeneous silicon nitride ceramic material. Distributed load-bearing positioning bosses (6) assembled with the turbine shaft (2) and the distributed load-bearing cover (3) are evenly distributed along the circumferential direction on the end surfaces of both sides of the wheel disk of the integral axial flow blade disk (1). The central portion of the distributed load-bearing positioning bosses (6) of the integral axial flow blade disk (1) is provided with through holes (7) assembled with bolts (4); The turbine shaft (2) has a flange (8) at one end connected to the integral axial flow blade disk (1); one end surface of the flange (8) of the turbine shaft (2) has distributed load-bearing positioning countersunk holes (9) uniformly distributed along the circumferential direction and assembled with the distributed load-bearing positioning bosses (6) of the integral axial flow blade disk (1); the bottom of the distributed load-bearing positioning countersunk holes (9) of the turbine shaft (2) has through holes (10) assembled with bolts (4); and interference fit is adopted between the distributed load-bearing positioning countersunk holes (9) on one side of the flange of the turbine shaft (2) and the distributed load-bearing positioning bosses (6) on the wheel end surface of the integral axial flow blade disk (1). One side end surface of the distributed load-bearing cover (3) is uniformly distributed along the circumferential direction with distributed load-bearing positioning countersunk holes (11) assembled with the distributed load-bearing positioning bosses (6) of the integral axial flow blade disk (1); the bottom of the distributed load-bearing positioning countersunk holes (11) of the distributed load-bearing cover (3) is provided with through holes (12) assembled with the bolts (4); the distributed load-bearing positioning countersunk holes (11) of the distributed load-bearing cover (3) and the distributed load-bearing positioning bosses (6) on the wheel end surface of the integral axial flow blade disk (1) are fitted by interference fit. The locking nut (5) is a threaded blind hole structure. The locking nut (5) is mounted on the bolt (4). One side of the locking nut (5) is pressed against one side end surface of the distributed load-bearing cover (3).

2. A high-speed axial-flow distributed load-bearing ceramic turbine rotor structure according to claim 1, characterized in that: The bolt (4) comprises a head, a bare rod and a stud. The head of the bolt (4) is a hexagonal cylindrical structure. The bolt (4) is assembled with the through hole (10) of the turbine shaft (2), the through hole (7) of the integral axial flow blade disk (1) and the through hole (12) of the distributed load-bearing cover (3). The external threaded portion of the bolt (4) is assembled with the locking nut (5).

3. A high-speed axial-flow distributed load-bearing ceramic turbine rotor structure according to claim 1, characterized in that: The integral axial flow blade disk (1) is assembled with the turbine shaft (2) via a distributed load-bearing positioning boss (6) and a distributed load-bearing positioning countersunk hole (9); the integral axial flow blade disk (1) is assembled with the distributed load-bearing cover (3) via a distributed load-bearing positioning boss (6) and a distributed load-bearing positioning countersunk hole (11); the assembly structure of the integral axial flow blade disk (1), the turbine shaft (2) and the distributed load-bearing cover (3) is thread-locked via bolts (4) and locking nuts (5), thereby forming a high-speed axial flow distributed load-bearing ceramic turbine rotor structure.

4. A high-speed axial-flow distributed load-bearing ceramic turbine rotor structure according to claim 1, characterized in that: The distributed load-bearing positioning bosses (6) on the end faces of both sides of the wheel disc of the integral axial flow blade disc (1) are respectively fitted with the distributed load-bearing positioning countersunk holes (11) of the distributed load-bearing cover (3) and the distributed load-bearing positioning countersunk holes (9) on one side of the flange of the turbine shaft (2) by interference fitting.

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