CN116658257A

CN116658257A - Rim sealing structure, turbine rotor and turbine movable blade

Info

Publication number: CN116658257A
Application number: CN202210149501.0A
Authority: CN
Inventors: 吴丽军; 张晓林; 彭皓
Original assignee: AECC Commercial Aircraft Engine Co Ltd
Current assignee: AECC Commercial Aircraft Engine Co Ltd
Priority date: 2022-02-18
Filing date: 2022-02-18
Publication date: 2023-08-29

Abstract

The utility model provides a rim seal structure can strengthen the pressure of the air current of sealing to promote the effect of sealing, including the movable vane seal portion and the quiet leaf seal portion that form the flow path of sealing, the movable vane seal portion includes the round booster blade that sets up along circumference, round booster blade is used for rotating together with the follow-up blade, plays the boost effect to the air current of sealing. A turbine rotor and a turbine bucket each have the supercharging blade.

Description

Rim sealing structure, turbine rotor and turbine movable blade

Technical Field

The invention relates to a rim sealing structure, a turbine rotor and a turbine movable blade.

Background

The civil aviation turbofan engine air system generally flows from the compressor to the turbine end through a pipeline or structures such as a disk cavity, a shaft cavity, a hole, a comb tooth and the like in the compressor, cools and seals the turbine and a fulcrum, and then is discharged into a main flow or enters a bearing cavity.

Rim seal in the aforementioned bleed air path is an important element in aircraft engine air system design, consisting of turbine vane lower edges and turbine blade lower edges. The purpose is to prevent gas from entering the disk cavity from the main flow channel under conditions where as little cold air as possible is used. The reasonable design of the rim sealing structure has important significance for controlling the air-entraining amount of the air system and ensuring the safety of the engine.

In the current mainstream aeroengine design, rim seal is generally by turbine stator blade lower extreme and turbine movable vane lower extreme formation fish-mouth seal, realizes preventing through fish-mouth seal structure that main runner gas from getting into the dish intracavity. Such a fish mouth sealing structure is described in patent specification publication number CN 104937214B. Considering that the rotor and the stator of the fish mouth structure are both made of metal, if the gap is too small, the risk of hard collision and hard collision is easy to occur, so that the normal operation of the engine is threatened, and the sealing gap is often larger.

In order to prevent fuel gas from entering the disc cavity, enough cool air needs to be designed to pass through the sealing structure, so that the sealing purpose is realized. Therefore, reasonable control of the sealing flow rate of the rim is very critical, because in certain limit working conditions, due to insufficient sealing gas pressure, the risk of backflow of fuel gas often exists.

Patent specification with publication number of CN 112922681A describes an aeroengine rim sealing structure, which is provided with a guide vane on the upper wall surface of a groove of a guide vane rim plate, and is used for increasing the resistance of fuel gas backflow and changing the direction and speed of cold air entering a main channel of a turbine. The sealing gap of the sealing structure is still larger.

How to more effectively realize rim sealing to prevent fuel gas from flowing backward is still to be further studied.

Disclosure of Invention

The invention aims to provide a rim sealing structure which can improve sealing air flow pressure so as to improve sealing effect.

Another object of the present invention is to provide a turbine rotor suitable for the aforementioned rim seal structure.

It is still another object of the present invention to provide a turbine bucket that is adapted to the aforementioned rim seal structure.

According to one aspect of the invention, the rim sealing structure comprises a movable blade sealing part and a stationary blade sealing part which form a sealing flow path, wherein the movable blade sealing part comprises a circle of supercharging blades arranged along the circumferential direction, and the circle of supercharging blades are used for rotating together with the movable blades to perform supercharging on sealing airflow.

In one or more embodiments, one of the blade seal and the vane seal includes a tab provided on the blade platform and the other includes a groove provided on the blade platform.

In one or more embodiments, the clearance between the supercharging blade and the vane seal is small enough to allow discrete rubbing between the supercharging blade and the vane seal when the engine is running at high speed.

In one or more embodiments, the supercharging blade is disposed on the blade edge plate corresponding to the movable blade seal portion and on a radially outer side of the tongue or a side wall of the groove.

In one or more embodiments, the bucket seal further includes a seal cavity including a sidewall of a bucket disc on which the supercharging blade is disposed.

According to another aspect of the invention, a turbine rotor includes a bucket seal portion including a ring of circumferentially disposed supercharging blades for rotation with the bucket to provide a supercharging effect on a seal air flow.

According to the turbine rotor blade, the turbine rotor blade comprises a blade edge plate, wherein the blade edge plate is provided with a rotor blade sealing part, and the rotor blade sealing part comprises a convex tongue or a groove.

After the cooling gas passes through the supercharging blades, the pressure is effectively improved, and the requirement of rim sealing can be effectively met. After a circle of blades are added on the turbine rotor, if the rotor and the stator are in collision and abrasion, the rotor and the stator are not in whole ring collision and abrasion, but in discrete collision and abrasion, and the influence of collision and abrasion on the engine is properly relieved.

Drawings

The above and other features, properties and advantages of the present invention will become more apparent from the following description in conjunction with the accompanying drawings and embodiments, in which:

fig. 1 is a schematic view of a seal flow path of a comparative example.

Fig. 2 is a schematic view of a rim sealing structure according to an embodiment of the present invention.

FIG. 3 is an isometric view of a turbine rotor according to an embodiment of the present invention.

FIG. 4 is an isometric view of a single turbine blade according to an embodiment of the present invention.

FIG. 5 is an isometric view of a partial turbine rotor according to another embodiment of the present invention.

FIG. 6 is an isometric view of a partial turbine rotor according to yet another embodiment of the present invention.

Detailed Description

Reference now will be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation, not limitation, of the invention. Indeed, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment, can be used with another embodiment to yield a still further embodiment. Accordingly, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.

Fig. 1 shows a rim seal structure of a comparative example in which a blade seal portion 3 includes a tongue 31 provided on one side of a blade rim plate 11 of a blade 1, and a vane seal portion 4 includes a groove 41 provided on one side of a blade rim plate 21 of a vane 2. All tabs 31 are in a ring configuration over the entire turbine rotor. All grooves 41 form a circle of annular grooves in the turbine stator. The movable vane sealing part 3 and the stationary vane sealing part 4 form a sealing effect, air flows from the disk center position of the turbine to the main flow channel of the turbine according to the direction shown by an arrow 5, the convex tongue 31 extends towards the groove 41 to form a bent flow channel, the sealing air pressure is larger than the pressure of fuel gas flowing backward in the main flow channel to form the sealing effect, however, the gap between the convex tongue 31 and the groove 41 is too large, and the fuel gas flowing backward is easy to form once the sealing pressure is insufficient. The embodiment shown in fig. 2 can solve this problem.

Fig. 2 shows a schematic view of a stage of a turbine comprising a turbine rotor comprising buckets 1 and bucket disks 10, and a turbine stator. The rotor disk 10 is provided with a circle of rotor blades 1 in the circumferential direction thereof, or the rotor blades 10 and the rotor blades 1 are integrally formed. The turbine stator comprises vanes or guide blades 2, and further comprises a turbine outer ring, which is not shown in the figures. The movable blade disc 10 is connected with a sealing disc 12, sealing comb teeth 120 are arranged on the outer periphery of the sealing disc 12, a sealing coating or a sealing honeycomb structure is arranged on the inner periphery of the stator inner ring 20, cooling air flow flowing downwards from the inside of the stationary blade 2 enters the sealing cavity 50 as sealing air flow, and then enters the turbine main runner from the sealing cavity 50 through the rim sealing structure. For the flow path arrangement of the seal air flow, reference is made to the specification of publication No. CN112523813a, which has been published by the applicant.

With continued reference to fig. 2, the rim seal structure includes a blade seal portion 3 and a vane seal portion 4 that form a seal flow path. The movable vane sealing part 3 comprises a circle of supercharging blades 7 arranged along the circumferential direction, and the circle of supercharging blades 7 are used for rotating together with the movable vane 1 to perform supercharging on sealing air flow. The supercharging blades 7 are arranged in the sealing flow path, the supercharging effect is achieved on the sealing airflow, the flowing direction of the sealing airflow can be understood by referring to the arrow 5 in fig. 1, after the supercharging blades 7 are used, the pressure is effectively improved, the sealing effect is correspondingly improved, therefore, the rim sealing requirement can be effectively met, and the fuel gas backflow is prevented. The position of a circle of supercharging vanes 7 is more fully shown in figure 3.

The blade seal portion 3 includes all portions defining the seal air flow, not limited to the tongue 31, such as other portions opposite the groove 41 or the stationary blade seal portion 4, such as portions of the flange 11 radially outward of the tongue 31 or portions of the blade disk 10 radially inward of the tongue 31, such as the seal cavity 50.

While one embodiment of the rim seal structure is described above, in other embodiments, there may be more detail in many respects relative to the above-described embodiments, and at least some of these details may be varied in many ways. At least some of this detail and some variations are described below in some examples.

Unlike the embodiment shown in fig. 2, in another example, the blade seal portion 3 is a groove, and the vane seal portion 4 is a tongue.

With continued reference to fig. 2, in some embodiments, the clearance between the supercharging blade 7 and the vane seal 4 is small enough to allow discrete rubbing between the supercharging blade 7 and the vane seal 4 when the engine is running at high speed, that is, the clearance between the upper edge of the supercharging blade 7 and the vane seal 4 is as small as the structure allows. The sealing effect is further improved because the gap is as small as possible. In addition, after a circle of blades are added on the turbine rotor, if the rotor and the stator are in collision and abrasion, the rotor and the stator are not in whole ring collision and abrasion, but in discrete collision and abrasion between the supercharging blades 7 and the stator blade sealing part 4, and the influence of collision and abrasion on the engine is properly relieved.

In the embodiment shown in fig. 2 and 3, the supercharging blades 7 are arranged radially outside the tongues 31 of the blade rim plate 11. In the embodiment shown in fig. 4, the blade edge plate 11 of the single turbine blade is provided with a plurality of supercharging blades 7, specifically, but not limited thereto, 3 blades, and the specific number is increased or decreased according to the type of engine and the required sealing effect. The gap between the upper edge of the supercharging blade 7 and the upper side wall of the recess 41 is as small as possible to further promote the sealing effect.

There may also be variations in the location of the placement of the booster blades 7, in the embodiment shown in fig. 5, the booster blades 7 are placed on the side walls of the bucket tray 10 in addition to the booster blades 7 placed on the tabs 31 of the bucket rims 11 of the buckets 1. Simultaneously with fig. 2, the side wall of the movable blade disk 10 provided with the supercharging blade 7 is also the side wall of the seal cavity 50. The supercharging blades are respectively arranged at two positions of the sealing flow path, so that the sealing effect is obviously enhanced, and the backflow of fuel gas is effectively prevented.

Fig. 6 shows another embodiment, in which the supercharging blades on the tongue 31 are omitted, only the supercharging blades 7 on the side wall of the movable vane disk 10 corresponding to the sealing cavity 50 are remained, and the sealing effect can be enhanced because the supercharging blades 7 have supercharging effect on the sealing air flow. In this embodiment as well, the clearance between the supercharging blade 7 and the vane seal portion 4 can be controlled to the minimum.

In some embodiments, the positions of the grooves 41 and the tabs 31 are interchanged, and the supercharging blades 7 are arranged on the upper side wall or the lower side wall of the grooves 41, which also has the effect of supercharging and sealing air flow and reducing sealing gaps.

It can be appreciated that the turbine rotor comprises the movable vane sealing part 3, a circle of supercharging blades 7 are circumferentially arranged on the movable vane sealing part 3, and the circle of supercharging blades 7 are used for rotating together with the follow-up vanes to perform supercharging on cooling air flow.

The turbine movable vane 1 comprises a vane edge plate 11, a movable vane sealing part 3 is arranged on the vane edge plate 11, at least one supercharging blade 7 is arranged on the upper edge of the movable vane sealing part 3, and the at least one supercharging blade 7 is used for rotating along with the follow-up blade to perform supercharging on cooling air flow.

While the invention has been described in terms of preferred embodiments, it is not intended to be limiting, but rather to the invention, as will occur to those skilled in the art, without departing from the spirit and scope of the invention. Therefore, any modification, equivalent variation and modification of the above embodiments according to the technical substance of the present invention fall within the protection scope defined by the claims of the present invention.

Claims

1. Rim seal structure, including the movable vane seal portion and the quiet leaf seal portion that form the seal flow path, its characterized in that, the movable vane seal portion includes round booster blade that sets up along circumference, round booster blade is used for following the blade and rotates together, plays the pressure boost effect to the sealed air current.

2. The rim seal structure according to claim 1, wherein one of the blade seal portion and the vane seal portion includes a tongue provided on a blade rim plate, and the other includes a groove provided on the blade rim plate.

3. The rim seal structure according to claim 1 or 2, wherein a gap between the supercharging blade and the vane seal portion is sufficiently small to allow discrete rubbing between the supercharging blade and the vane seal portion when an engine is running at a high speed.

4. The rim seal structure according to claim 2, wherein the supercharging blade is provided on the blade rim plate corresponding to the blade seal portion and on a radially outer side of the tongue or a side wall of the groove.

5. The rim seal structure of claim 2 or 4, wherein the bucket seal further comprises a seal cavity including a sidewall of a bucket disc on which the supercharging bucket is disposed.

6. Turbine rotor, including movable vane seal portion, its characterized in that, the movable vane seal portion includes round booster blade that sets up along circumference, round booster blade is used for rotating together with the movable vane, plays the pressure boost effect to the sealed air current.

7. The turbine rotor of claim 6, wherein the bucket seal comprises a tab or groove provided on the bucket lip.

8. The turbine rotor of claim 7 wherein said booster blades are disposed on said blade rims and radially outward of said tabs or on sidewalls of said grooves.

9. The turbine rotor of claim 7 or 8, wherein the bucket seal further comprises a seal cavity comprising a sidewall of a bucket disc on which the booster blades are disposed.

10. The utility model provides a turbine movable vane, includes the blade edge board, be provided with movable vane seal portion on the blade edge board, movable vane seal portion includes tongue or recess, its characterized in that, movable vane seal portion is still including at least one piece supercharging blade that sets up on the lateral wall of tongue or recess, at least one piece supercharging blade is used for following the blade and rotates together, plays the pressure boost effect to the sealed air current.