Rotary flow guide disc connecting structure for reducing tenon connecting temperature of turbine disc

Abstract

The invention relates to the technical field of aero-engines, and discloses a rotary flow guide disc connecting structure for reducing turbine disc tenon connecting temperature, which comprises a rotary flow guide disc, first flow deflectors and second flow deflectors, and the second flow deflectors are arranged at downstream positions of flow guide channels between two adjacent first flow deflectors. A certain number of flow deflectors are evenly distributed in the circumferential direction of the rotary flow guide disc, downstream cold air flow of a rear cavity of the turbine disc can flow into the position between the tenon and the mortise along the inclined holes of the turbine disc radial plate through rotary compression, heat transfer of fuel gas to the wheel disc through the blades is effectively cooled and blocked, and therefore the average temperature of the wheel disc is reduced, and the service life of the wheel disc is prolonged. The temperature difference between the rim and the wheel center is reduced, and the thermal stress of the turbine disc is reduced; in addition, the flow deflectors have long and short structures, and the short second flow deflectors are arranged between the rear half parts of the long first flow deflector channels, so that airflow separation can be inhibited, turbulence and vortex of airflow can be reduced, and energy loss of the airflow can be reduced.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of an aero-engine, and discloses a rotating flow guide disc connecting structure for reducing the temperature of a turbine disc tenon connection. BACKGROUND

[0002] The turbine parts of an aero-engine bear severe thermal and mechanical loads, and the working conditions of rotor parts, in particular rotor blades and a rotor disc, are even more severe. In order to ensure that the turbine rotor parts can work safely and reliably in a required service life, the turbine rotor is mainly cooled under the condition of reasonable selection of materials. According to the working conditions of the turbine and the overall structural layout, appropriate cooling flow paths and structures are designed, and the heat of the turbine rotor parts is taken away by cooling air so that the turbine rotor parts can be kept at an allowable temperature in each working state.

[0003] The tenon and the tenon groove of the turbine rotor part are at the connecting part of the blade and the disc, and are the most intense heat conduction area from the blade to the disc. In order to more effectively cool and block the heat transfer of the gas through the blade to the disc, a slant hole is needed to be arranged in the disc rim area in the design of the heat transfer flow path of the engine, the airflow of the turbine disc core is guided to the turbine disc rear through the hole arranged on the turbine shaft and the flow guide structure, so as to reduce the average temperature of the disc. However, the existing flow guide structure still has some deficiencies in application, for example, the flow guide effect is not ideal, and there are phenomena of turbulent flow and vortex flow; the design of part of the flow guide structure is relatively complex, which increases the difficulty and cost of the manufacturing process. SUMMARY

[0004] The application aims to provide a rotating flow guide disc connecting structure for reducing the temperature of a turbine disc tenon connection, which can reduce the thermal stress of the turbine disc, effectively inhibit airflow separation, reduce turbulent flow and vortex flow of the airflow, and reduce energy loss of the airflow.

[0005] In order to achieve the above technical effects, the technical scheme adopted by the application is as follows: A rotating flow guide disc connecting structure for reducing the temperature of a turbine disc tenon connection, comprising: A rotating flow guide disc coaxially fixed to a turbine disc in a direction away from the airflow; A plurality of first flow guide pieces are uniformly arranged on the rotating flow guide disc in a ring shape, and the first flow guide pieces are located at the gap position between the rotating flow guide disc and the turbine disc. An airflow guide channel is formed between two adjacent first flow guide pieces, and the first flow guide pieces are used for compressing the cold airflow downstream of the airflow guide channel; A second flow guide piece is arranged at a downstream position of the airflow guide channel between two adjacent first flow guide pieces, and the length of the second flow guide piece is smaller than that of the first flow guide piece.

[0006] Furthermore, the outer edge of the rotating guide disk is provided with a slot that fits with the rear mounting edge of the turbine disk, and the slot and the rear mounting edge are fixed by mounting pins.

[0007] Furthermore, the slot is a U-shaped slot, and a through hole is provided on the support arm of the U-shaped slot facing away from the incoming flow. A countersunk hole is provided on the other support arm of the U-shaped slot. The mounting pin passes through the through hole, the rear mounting edge and the countersunk hole in sequence, and is axially positioned by the bottom of the countersunk hole. The mounting pin is deformed and locked by interference fit.

[0008] Furthermore, a protrusion is provided on the rear mounting edge of the turbine disk, which engages with the U-shaped groove, and the protrusion and the U-shaped groove are interference-fitted along the engine axis.

[0009] Furthermore, the protrusion on the rear mounting edge is provided with an inverted U-shaped groove that mates with the mounting pin, and a radial clearance fit is provided between the inverted U-shaped groove and the mounting pin.

[0010] Furthermore, the protrusion and the bottom of the U-shaped slot are radially clearance fitted.

[0011] Furthermore, the ends of the first and second guide vanes near the outer edge of the turbine disk spokes are respectively clearance-fitted with the turbine disk end face; the ends of the first and second guide vanes near the center of the turbine disk are respectively interference-fitted with the turbine disk end face.

[0012] Furthermore, the rotating guide disk has several keyways evenly distributed circumferentially away from the direction of the incoming flow, which are used to rotate the rotating guide disk when it is assembled with the turbine disk.

[0013] Furthermore, the radial deflection angle of the first guide vane is obtained through analysis using the following method: An analytical model of the flow channel, including a rotating guide disk, a turbine disk, a first guide vane, and a second guide vane, is constructed. Using the cold airflow parameters under the test conditions as input, and the design dimensions of the second guide vane, the relative installation position, and the design dimensions of the first guide vane as constraints, the simulation obtains the absolute velocity of the inlet airflow, the absolute velocity of the outlet airflow, the absolute velocity of the outlet airflow, the outlet pressure, and the outlet temperature of the guide channel under different radial deflection angles of the first guide vane. Based on the absolute velocity of the inlet airflow, inlet pressure, absolute velocity of the outlet airflow, outlet pressure, and outlet temperature of the guide channel, a functional relationship model is constructed between the aerodynamic efficiency of the rotating guide disk and the radial deflection angle of the first guide vane. Using the design dimensions of the second guide vane, its relative installation position, and the design dimensions of the first guide vane as constraints, and taking the maximum output value of the functional relationship model as the optimization objective, the radial deflection angle of the first guide vane is optimized to obtain the range of values ​​for the radial deflection angle of the first guide vane.

[0014] Furthermore, the functional relationship model between the aerodynamic efficiency of the rotating guide disk and the radial deflection angle of the first guide vane is as follows: ,in To improve the aerodynamic efficiency of the rotating guide plate. The isentropic index of the cold airflow. The gas constant is The outlet temperature of the flow guide channel. The outlet pressure of the flow channel, The absolute velocity of the outlet airflow. The inlet pressure of the flow channel, The absolute velocity of the inlet airflow. The radial deflection angle of the first guide vane. This refers to the radial angle between the inlet and outlet ends of the first guide vane under the corresponding radial deflection angle.

[0015] Compared with the prior art, the beneficial effects of this invention are: 1. This invention uses a certain number of guide vanes evenly distributed around the circumference of a rotating guide disk. Through rotational compression, the downstream cold airflow in the rear cavity of the turbine disk can flow into the space between the tenon and the mortise through the oblique holes of the turbine disk spokes. This effectively cools and blocks the heat transfer of the gas from the blades to the disk, thereby reducing the average temperature of the disk, reducing the temperature difference between the rim and the center, and reducing the thermal stress of the turbine disk. 2. The guide vane of the present invention has two structures, long and short. A short second guide vane is set between the rear half of the long first guide vane channel, which can suppress airflow separation, reduce airflow turbulence and eddies, and reduce airflow energy loss. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the rotating guide disk connection structure in the embodiment; Figure 2 This is a schematic diagram showing the positional relationship of the first and second guide vanes on the rotating guide disk in the embodiment. Figure 3 This is a schematic diagram illustrating the cooperation between the first guide vane and the turbine disk in the embodiment; Figure 4 This is a schematic diagram of the U-shaped card slot in the embodiment; Figure 5 This is a schematic diagram illustrating the fit between the U-shaped slot and the inverted U-shaped slot in the embodiment; Among them, 1. Rotary guide plate; 2. Turbine plate; 3. First guide vane; 4. Second guide vane; 5. Assembly pin; 6. U-shaped groove; 601. Through hole; 602. Countersunk hole; 603. Radial flange; 7. Protrusion; 701. Inverted U-shaped groove; 8. Keyway. Detailed Implementation

[0017] The present invention will now be described in further detail with reference to the embodiments and accompanying drawings. However, this should not be construed as limiting the scope of the above-described subject matter of the present invention to the following embodiments; all technologies implemented based on the content of the present invention fall within the scope of the present invention.

[0018] Example See Figures 1 to 5 A rotating guide disk connection structure for reducing the temperature of turbine disk tenon joints, comprising: A rotating guide disk 1 is coaxially fixed to the turbine disk 2 in a direction opposite to the incoming flow. Multiple first guide vanes 3 are evenly arranged circumferentially on the rotating guide disk 1, and the first guide vanes 3 are located in the gap between the rotating guide disk 1 and the turbine disk 2. A guide channel for cold airflow is formed between two adjacent first guide vanes 3, and the first guide vanes 3 are used to compress the cold airflow downstream of the guide channel. The second guide vane 4 is located downstream of the guide channel between two adjacent first guide vanes 3, and the length of the second guide vane 4 is less than the length of the first guide vane 3.

[0019] In this embodiment, by uniformly distributing a certain number of guide vanes in the circumferential direction of the rotating guide disk 1, the downstream cold airflow of the turbine disk 2 can flow into the space between the tenon and the mortise through the oblique holes of the turbine disk 2 spokes by rotational compression. This effectively cools and blocks the heat transfer of the gas from the blades to the disk, thereby reducing the average temperature of the disk, reducing the temperature difference between the rim and the center, and reducing the thermal stress of the turbine disk 2. In addition, the guide vanes have two structures, long and short. A short second guide vane 4 is set between the rear half of the long first guide vane 3 channel, which can suppress airflow separation, reduce airflow turbulence and eddies, reduce airflow energy loss, and thus enhance the cooling of the blade tenon and the disk mortise.

[0020] In this embodiment, both the first guide vane 3 and the second guide vane 4 are flat plate structures, making their manufacturing process relatively simple. Depending on the airflow velocity and direction in the rear cavity of the turbine disk 2 under different operating conditions, a positive angle design can be adopted at the inlet of the first guide vane 3 or the second guide vane 4. By controlling the radial angle between the first guide vane 3, the second guide vane 4, and the rotating guide disk 1, the airflow direction and velocity flowing into the first guide vane 3 can be controlled, thereby improving airflow stability.

[0021] In this embodiment, the outer edge of the rotating guide disk 1 is provided with a slot that fits with the rear mounting edge of the turbine disk 2, and the slot and the rear mounting edge are fixed by mounting pins 5.

[0022] To facilitate the assembly of the rotating guide disk 1 and the turbine disk 2, the slot in this embodiment is a U-shaped slot 6. The support arm of the U-shaped slot 6 facing away from the incoming flow can be multiple circumferentially distributed radial flanges 603. Each radial flange 603 has a through hole 601. The other support arm of the U-shaped slot 6 (which can be a ring structure) has a countersunk hole 602. The mounting pin 5 passes through the through hole 601, the rear mounting edge, and the countersunk hole 602 in sequence, and is axially positioned by the bottom of the countersunk hole 602. The mounting pin 5 is deformed and locked by the interference fit, so that a stable and reliable connection can be formed between the rotating guide disk 1 and the rear mounting edge of the turbine disk 2, ensuring that the two will not loosen or separate under conditions such as high-speed rotation of the turbine disk 2 and exposure to complex airflow impact.

[0023] In this embodiment, a protrusion 7 is provided on the rear mounting edge of the turbine disk 2, which engages with the U-shaped groove 6. The protrusion 7 and the U-shaped groove 6 are interference-fitted along the engine axial direction. The protrusion 7 on the rear mounting edge is provided with an inverted U-shaped groove 701 that engages with the mounting pin 5. A radial clearance fit is provided between the inverted U-shaped groove 701 and the mounting pin 5. During assembly, the rotating guide disk 1 is inserted into the rear mounting edge of the turbine disk 2. By rotating, the through hole 601 of the radial flange 603 of the rotating guide disk 1 is aligned with the center of the inverted U-shaped groove 701 of the protrusion 7 on the rear mounting edge of the turbine disk 2. Because of the radial clearance fit between the protrusion 7 and the bottom of the U-shaped groove 6, radial centering of the rotating guide disk 1 is convenient during installation. During operation, due to the temperature difference between the rotating guide disk 1 and the turbine disk 2, the radial displacement of the turbine disk 2 is greater than the radial displacement of the rotating guide disk 1, allowing the radial flange 603 of the rotating guide disk 1 to move radially along the inverted U-shaped groove 701.

[0024] During operation, the central teeth of the rotating guide disk 1 bend and deform under centrifugal force, causing a separation between the inlets of the first guide vane 3 and the second guide vane 4 and the axial direction of the turbine disk 2. To improve efficiency, in this embodiment, both the first guide vane 3 and the second guide vane 4 are inclined at the same angle along the spokes of the turbine disk 2. Furthermore, the ends of the first guide vane 3 and the second guide vane 4, near the outer edge of the spokes of the turbine disk 2, are clearance-fitted with the end face of the turbine disk 2, resulting in a certain clearance between the outer outlet ends of the first guide vane 3 and the corresponding positions of the turbine disk 2 body (e.g., ...). Figure 3The ΔL1 in the figure reduces assembly difficulty, and when the rotating guide disk 1 rotates, the centrifugal load it generates will not be transmitted to the turbine disk 2, thus reducing the load on the turbine disk 2. Furthermore, to compensate for the axial deformation generated when the rotating guide disk 1 rotates, the ends of the first guide vane 3 and the second guide vane 4 near the center of the turbine disk 2 are respectively interference-fitted with the end face of the turbine disk 2, so that a certain amount of interference is formed axially between the downstream positions of the first guide vane 3 and the second guide vane 4 and the corresponding positions of the turbine disk 2 body (e.g., ΔL1). Figure 3 (ΔL2 in the middle).

[0025] In some other embodiments, the interference amount ΔL2 can be obtained from the finite element modeling analysis of the rotor. By analyzing the axial deformation of the disk core teeth of the rotating guide disk 1 under centrifugal action under different working conditions through finite element modeling, the range of values ​​for the interference amount ΔL2 is comprehensively given.

[0026] Furthermore, in this embodiment, the radial deflection angle of the first guide vane 3 is obtained through analysis using the following method: S1. Construct an analysis model of the flow channel including a rotating guide disk 1, a turbine disk 2, a first guide vane 3, and a second guide vane 4; S2. Using the cold air parameters (such as temperature, pressure, flow rate, density, etc.) under the test conditions as input, and the design dimensions of the second guide vane 4, relative installation position, and the design dimensions of the first guide vane 3 as constraints, the simulation obtains the absolute velocity of the inlet airflow, inlet pressure, absolute velocity of the outlet airflow, outlet pressure, and outlet temperature of the guide channel under different radial deflection angles of the first guide vane 3. S3. Based on the absolute velocity of the inlet airflow, the inlet pressure, the absolute velocity of the outlet airflow, the outlet pressure, and the outlet temperature of the guide channel, construct a functional relationship model between the aerodynamic efficiency of the rotating guide disk 1 and the radial deflection angle of the first guide vane 3. In this embodiment, the functional relationship model between the aerodynamic efficiency of the rotating guide disk 1 and the radial deflection angle of the first guide vane 3 is as follows: ,in For the aerodynamic efficiency of the rotating guide plate 1, The isentropic index of the cold airflow. The gas constant is The outlet temperature of the flow guide channel. The outlet pressure of the flow channel, The absolute velocity of the outlet airflow. The inlet pressure of the flow channel, The absolute velocity of the inlet airflow. The radial deflection angle of the first guide vane 3. To correspond to the radial angle between the inlet and outlet ends of the first guide vane 3 under the radial deflection angle (e.g. Figure 2As shown, r1 is the radial height of the inlet end of the first guide vane 3, and r2 is the radial height of the outlet end of the first guide vane 3. (The angular velocity of the rotating guide disk 1 or turbine disk 2). The construction of this functional relationship model comprehensively considers the influence of pressure, temperature, airflow velocity at the inlet and outlet of the guide channel, as well as the radial deflection angle of the first guide vane 3. It can accurately reflect the change in the aerodynamic efficiency of the rotating guide disk 1 under the radial deflection angle of the first guide vane 3. In practical applications, the optimal radial deflection angle of the first guide vane 3 can be obtained by analyzing the model according to the required aerodynamic efficiency of the rotating guide disk 1, thereby achieving the purpose of reducing the joint temperature of the turbine disk 2. This provides strong support for the optimized design of the rotating guide disk 1 and the improvement of the working performance of the joint of the turbine disk 2.

[0027] S4. Using the design dimensions of the second guide vane 4, its relative installation position, and the design dimensions of the first guide vane 3 as constraints, and taking the maximum output value of the functional relationship model as the optimization objective, the radial deflection angle of the first guide vane 3 is optimized to obtain the range of values ​​for the radial deflection angle of the first guide vane 3.

[0028] In this embodiment, the rotating guide disk 1 has several keyways 8 evenly distributed circumferentially away from the direction of the incoming flow, which are used to rotate the rotating guide disk 1 when it is assembled with the turbine disk 2.

[0029] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A rotating guide disk connection structure for reducing the temperature of turbine disk tenon joints, characterized in that, include: A rotating guide disk, which is coaxially fixed to the turbine disk in a direction opposite to the incoming flow; Multiple first guide vanes are evenly arranged circumferentially on the rotating guide disk, and the first guide vanes are located in the gap between the rotating guide disk and the turbine disk. A guide channel for cold airflow is formed between two adjacent first guide vanes, and the first guide vanes are used to compress the cold airflow downstream of the guide channel. The second guide vane is located downstream of the guide channel between two adjacent first guide vanes, and the length of the second guide vane is less than the length of the first guide vane.

2. The rotating guide disk connection structure according to claim 1, characterized in that, The outer edge of the rotating guide disk is provided with a slot that fits with the rear mounting edge of the turbine disk, and the slot and the rear mounting edge are fixed by mounting pins.

3. The rotating guide disk connection structure according to claim 2, characterized in that, The slot is a U-shaped slot. A through hole is provided on the support arm of the U-shaped slot facing away from the incoming flow, and a countersunk hole is provided on the other support arm of the U-shaped slot. The mounting pin passes through the through hole, the rear mounting edge and the countersunk hole in sequence, and is axially positioned by the bottom of the countersunk hole. The mounting pin is deformed and locked by interference fit.

4. The rotating guide disk connection structure according to claim 3, characterized in that, The rear mounting edge of the turbine disk is provided with a protrusion that engages with the U-shaped slot, and the protrusion and the U-shaped slot are interference-fitted along the engine axis.

5. The rotating guide disk connection structure according to claim 4, characterized in that, The protrusion on the rear mounting edge is provided with an inverted U-shaped groove that mates with the mounting pin, and a radial clearance fit is provided between the inverted U-shaped groove and the mounting pin.

6. The rotating guide disk connection structure according to claim 4, characterized in that, The protrusion and the bottom of the U-shaped slot are fitted with a radial clearance.

7. The rotating guide disk connection structure according to claim 1, characterized in that, The ends of the first and second guide vanes near the outer edge of the turbine disk spokes are clearance-fitted with the end face of the turbine disk; the ends of the first and second guide vanes near the center of the turbine disk are interference-fitted with the end face of the turbine disk.

8. The rotating guide disk connection structure according to claim 1, characterized in that, The rotating guide disk has several keyways evenly distributed circumferentially away from the direction of the incoming flow, which are used to rotate the rotating guide disk when it is assembled with the turbine disk.

9. The rotating guide disk connection structure according to claim 1, characterized in that, The radial deflection angle of the first guide vane was obtained through analysis using the following method: Construct an analytical model of the flow channel that includes a rotating guide disk, a turbine disk, a first guide vane, and a second guide vane; Using the cold airflow parameters under the test conditions as input, and the design dimensions of the second guide vane, the relative installation position, and the design dimensions of the first guide vane as constraints, the simulation obtains the absolute velocity of the inlet airflow, the absolute velocity of the outlet airflow, the absolute velocity of the outlet airflow, the outlet pressure, and the outlet temperature of the guide channel under different radial deflection angles of the first guide vane. Based on the absolute velocity of the inlet airflow, inlet pressure, absolute velocity of the outlet airflow, outlet pressure, and outlet temperature of the guide channel, a functional relationship model is constructed between the aerodynamic efficiency of the rotating guide disk and the radial deflection angle of the first guide vane. Using the design dimensions of the second guide vane, its relative installation position, and the design dimensions of the first guide vane as constraints, and taking the maximum output value of the functional relationship model as the optimization objective, the radial deflection angle of the first guide vane is optimized to obtain the range of values ​​for the radial deflection angle of the first guide vane.

10. The rotating guide disk connection structure according to claim 9, characterized in that, The constructed functional relationship model between the aerodynamic efficiency of the rotating guide disk and the radial deflection angle of the first guide vane is as follows: ,in To improve the aerodynamic efficiency of the rotating guide plate. The isentropic index of the cold airflow. The gas constant is The outlet temperature of the flow guide channel. The outlet pressure of the flow channel, The absolute velocity of the outlet airflow. The inlet pressure of the flow channel, The absolute velocity of the inlet airflow. The radial deflection angle of the first guide vane. This refers to the radial angle between the inlet and outlet ends of the first guide vane under the corresponding radial deflection angle.

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