A turbine disc shaft connecting structure for improving robustness of an aero-engine

Abstract

The application belongs to the field of aero-engine design and relates to a turbine disc shaft connecting structure for improving the robustness of an aero-engine, which comprises a turbine disc and a turbine shaft, and a slanting conical wall is arranged on the turbine disc, the slanting conical wall is provided with a ventilation hole, the slanting conical wall comprises a flat section and a vertical section, and the flat section is arranged along the aero-engine axial direction and is provided with an extension section. The slanting conical wall forms a bending structure through the vertical section and the flat section, the slanting conical wall of the turbine disc is lengthened, the ventilation hole of the turbine disc conical wall is ensured to have the same ventilation area, and the problem of weakening of the conical wall strength caused by the ventilation hole is reduced; the mass center distance of the turbine disc and the turbine shaft is increased through the arrangement of the extension section, the deformation, inclination and mass unbalance excitation load generated in the turbine disc rotation process are attenuated on the force transmission path, the load acting on the turbine shaft and the main fulcrum bearing is reduced, the fulcrum outer ring inclination problem caused by the turbine disc deformation is reduced, and the deformation coordination is improved.

Description

Technical Field

[0001] This application belongs to the field of aero-engine design, and specifically relates to a turbine disk shaft connection structure for improving the robustness of aero-engines. Background Technology

[0002] The turbine rotor system of an aero-engine operates in a high-temperature, high-pressure environment. Simultaneously, the turbine rotor is heavy, has a large moment of inertia, and operates at speeds exceeding 10,000 rpm, resulting in extremely high loads on the turbine rotor. For example... Figure 1 As shown, a turbine rotor is generally composed of a turbine disk and a turbine shaft. Whether the turbine disk and shaft connection structure is robust and reliable will seriously affect the connection stiffness of the turbine rotor and the contact state of the connection surface, which in turn will affect the dynamic characteristics, vibration characteristics, and long-term use of the main support bearing of the whole machine.

[0003] When designing the turbine rotor shaft connection structure, it is necessary to comprehensively consider the working environment of the entire engine structure system. Under the condition of meeting the structural strength requirements, the deformation coordination of the connection structure and related components should also be considered to ensure that the turbine rotor meets the engine's safety and reliability requirements in the full range of operating conditions.

[0004] 1) Due to the limited structural space at the turbine disk shaft connection, the radial deformation and tilting generated during the operation of the turbine disk will transmit a large load to the disk shaft connection structure, resulting in high local static stress in the connection structure and affecting the reliability of the connection structure.

[0005] 2) To meet performance requirements, the rotor speed of aero engines is increasing. At high speeds, the rotor undergoes bending deformation. The gyroscopic torque of the turbine disk is transmitted to the disk-shaft connection structure and the turbine rotor support bearing, resulting in excessive dynamic stress in the connection structure and excessive dynamic load on the support, which affects the overall reliability of the engine.

[0006] 3) The excitation generated by the deformation, tilting and mass imbalance of the turbine disk during engine operation will be transmitted to the turbine shaft and then to the main bearing, which will have an adverse effect on the overall rotor dynamics and vibration, and will also be detrimental to the long-term operation of the main bearing.

[0007] Therefore, how to achieve stable operation of the turbine disk shaft within the entire envelope range is a problem that needs to be solved. Summary of the Invention

[0008] The purpose of this application is to provide a turbine disk shaft connection structure that improves the robustness of aero engines, thereby solving the problems of excessive local static stress and excessive dynamic load on the support point in the prior art.

[0009] The technical solution of this application is: a turbine disk shaft connection structure for improving the robustness of an aero-engine, including a turbine disk and a turbine shaft. An inclined conical wall extends from the inclined turbine disk. The conical wall includes a straight part and a vertical part. The vertical part is integrally connected to the end of the straight part near the turbine shaft. The vertical part is in contact with the side wall surface of the turbine shaft. The straight part is arranged along the axial direction of the aero-engine and has an extension section.

[0010] Preferably, the vertical part and the turbine shaft are radially interference-fitted through a first stop.

[0011] Preferably, a rear grate ring is provided on the side wall of the turbine shaft, and a long bolt is threadedly connected between the rear grate ring and the turbine shaft and the vertical part. A support plate nut is threadedly connected to the upper end of the long bolt, and the rear grate ring and the turbine shaft are positioned by a second stop.

[0012] This application discloses a turbine disk-shaft connection structure for improving the robustness of an aero-engine, comprising a turbine disk and a turbine shaft. A tapered wall extends from the turbine disk, and the tapered wall has vent holes. The tapered wall includes a straight portion and a vertical portion. The straight portion is arranged along the aero-engine axis and has an extension section. The tapered wall forms a bending structure through the vertical and straight portions, lengthening the tapered wall of the turbine disk. This reduces the weakening of the tapered wall strength caused by opening vent holes, while ensuring the same ventilation area. By setting the extension section, the distance between the centers of mass of the turbine disk and the turbine shaft is increased, attenuating the deformation, tilting, and mass imbalance excitation loads generated during turbine disk rotation onto the force transmission path. This reduces the load acting on the turbine shaft and the main bearing, reduces the tilting problem of the outer ring of the bearing caused by turbine disk deformation, and improves deformation coordination. Attached Figure Description

[0013] To more clearly illustrate the technical solutions provided in this application, the accompanying drawings will be briefly described below. Obviously, the drawings described below are merely some embodiments of this application.

[0014] Figure 1 This is a schematic diagram of the turbine disk shaft structure in the background art;

[0015] Figure 2 This is a schematic diagram of the overall structure of the disk shaft in this application;

[0016] Figure 3 This is a schematic diagram comparing the loosening torque of the long bolt connecting the turbine disk shaft in this application.

[0017] 1. Turbine disk; 2. Turbine shaft; 3. Straight section; 4. Vertical section; 5. Long bolt; 6. Vent hole; 7. First stop; 8. Second stop; 9. Rear grate ring; 10. Support plate nut; 11. Extension section. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings.

[0019] A turbine disk shaft connection structure to improve the robustness of aero engines, such as Figure 2 As shown, it includes a turbine disk 1 and a turbine shaft 2. A main pivot bearing is provided between the turbine disk 1 and the turbine shaft 2. The structure of the turbine disk 1, the turbine shaft 2 and the main pivot bearing is the same as the existing structure, and will not be described in detail here.

[0020] A tapered wall extends from the turbine disk 1, and a vent 6 is provided on the tapered wall. The tapered wall includes a straight part 3 and a vertical part 4. The vertical part 4 is integrally connected to one end of the straight part 3 near the turbine shaft 2. The vertical part 4 is in contact with the side wall of the turbine shaft 2. The straight part 3 is arranged along the axial direction of the aero engine and an extension section 11 is provided on the straight part 3.

[0021] The inclined conical wall forms a bending structure through the vertical part 4 and the horizontal part 3, which lengthens the inclined conical wall of the turbine disk 1. This reduces the problem of weakening of the conical wall strength caused by opening the vent hole 6, while ensuring the same ventilation area.

[0022] By setting the extended section 11, the distance between the centers of mass of the turbine disk 1 and the turbine shaft 2 is increased, which attenuates the deformation, tilting and mass imbalance excitation load generated during the rotation of the turbine disk 1 on the force transmission path, reduces the load acting on the turbine shaft 2 and the main support bearing, reduces the problem of the outer ring tilt of the support caused by the deformation of the turbine disk 1, and improves the deformation coordination.

[0023] After adopting the above structure, the loosening torque of the turbine disk shaft 1 connection bolts before and after the improvement (a typical indicator of the robustness of the turbine disk shaft 1 connection structure) was analyzed, such as... Figure 3 As shown, the loosening torques of disassembly 001-01 and 001-02 are the loosening torques of the long bolt 5 on the turbine disk 1 shaft of the engine before improvement (code: 001), during the first and second disassembly. The loosening torques of disassembly 002-01 and 002-02 are the loosening torques of the long bolt 5 on the turbine disk 1 shaft of the engine after improvement (code: 002). By comparing the loosening torques and assembly tightening torques of the two disassembly operations before and after improvement, it can be found that the loosening torques of the two disassembly operations before improvement are 3.2 times and 1.8 times the assembly tightening torque, respectively. The dispersion of the loosening torques between the two disassembly operations is large, and the disassembly loosening torque is much larger than the assembly tightening torque, indicating insufficient stability of the turbine disk 1 shaft operation. The loosening torques of the two disassembly operations after improvement are 1.45 times and 1.46 times the assembly tightening torque, respectively. The loosening torques of the two disassembly operations are basically the same, indicating better stability of the turbine disk 1 shaft operation.

[0024] Preferably, the vertical part 4 and the turbine shaft 2 are radially interference-fitted through the first stop 7 to ensure radial and circumferential positioning, prevent relative slippage during rotor movement, and enhance the stability of the connection structure.

[0025] Preferably, a rear-shaft grate ring 9 is provided on the side wall of the turbine shaft 2. A long bolt 5 is threadedly connected between the rear-shaft grate ring 9 and the turbine shaft 2 and the vertical part 4. A support plate nut 10 is threadedly connected to the upper end of the long bolt 5. The rear-shaft grate ring 9 and the turbine shaft 2 are positioned by a second stop 8. The long bolt 5 passes through the three layers of rotor components. Under the combined action of the support plate nut 10 with a certain tightening torque, the rotor components are axially pressed together. The long bolt 5 and the turbine shaft 2 adopt a small clearance fit to ensure the positioning of the turbine disk 1 and to ensure the amount of compression.

[0026] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A turbine disk shaft connection structure for improving the robustness of aero engines, characterized in that: It includes a turbine disk (1) and a turbine shaft (2). The turbine disk (1) has a tapered wall extending out. The tapered wall includes a straight part (3) and a vertical part (4). The vertical part (4) is integrally connected to one end of the straight part (3) near the turbine shaft (2). The vertical part (4) is in contact with the side wall of the turbine shaft (2). The straight part (3) is arranged along the axial direction of the aircraft engine and has an extension section (11). The vertical part (4) and the turbine shaft (2) are radially interference-fitted through the first stop (7); The turbine shaft (2) has a rear grate ring (9) on its side wall. The rear grate ring (9) is threadedly connected to the turbine shaft (2) and the vertical part (4) by a long bolt (5). The upper end of the long bolt (5) is threadedly connected to a support plate nut (10). The rear grate ring (9) and the turbine shaft (2) are positioned by a second stop (8).

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