CN113530682A

CN113530682A - Turbine blade cool air supply device and aircraft engine

Info

Publication number: CN113530682A
Application number: CN202010285801.2A
Authority: CN
Inventors: 邓双国; 孙平平; 郭晓杰
Original assignee: AECC Commercial Aircraft Engine Co Ltd
Current assignee: AECC Commercial Aircraft Engine Co Ltd
Priority date: 2020-04-13
Filing date: 2020-04-13
Publication date: 2021-10-22

Abstract

The invention relates to a turbine blade cold air supply device and an aircraft engine, wherein the cold air supply device comprises a gas collecting cavity (1), a gas guide pipe (3), a rectifying device (4) and a plurality of turbine blades (2), the plurality of turbine blades (2) are arranged at the downstream of the gas collecting cavity (1), the gas guide pipe (3) is communicated with the gas collecting cavity (1) to convey cold air for cooling the turbine blades (2) into the gas collecting cavity (1), and the rectifying device (4) is arranged at an outlet of the gas guide pipe (3) and is configured to enable airflow flowing out of the gas guide pipe (3) to be more uniform. According to the invention, the rectifying device is arranged, so that the airflow flowing out of the air guide pipe is more uniform, and the jet speed of the airflow can be reduced, so that each turbine blade is cooled more uniformly, local deformation of each turbine blade caused by nonuniform cooling is avoided, and the safety of the engine is improved.

Description

Turbine blade cool air supply device and aircraft engine

Technical Field

The invention relates to the technical field of turbine wheel cooling, in particular to a turbine blade cold air supply device and an aircraft engine.

Background

The engine guides air from the blade tip of the compressor to the turbine to cool the turbine blades and other parts. The cooling gas is led out through a plurality of bleed pipes, the bleed pipes are radially connected to a mounting seat on the turbine casing, and the mounting seat is radially inwards connected with the annular gas collecting cavity. And the downstream of the gas collecting cavity is provided with a turbine guide vane or a turbine interstage casing rectifying blade. The bleed pipes are generally uniformly distributed along the circumferential direction, the turbine guide vanes and the rectifying blades are of discrete structures in the circumferential direction, and a plurality of bleed pipes are distributed along the circumferential direction. The cold air enters the air collecting cavity through the air guide pipe and the mounting seat, then enters the turbine guide vanes or the rectifying vanes, and enters the interior of the engine for further cooling after cooling the vanes.

The gas collecting cavity is an annular cavity inside the engine and is used for collecting airflow of the gas guide pipe and enabling the airflow to enter a downstream cooling turbine guide vane or a rectification blade after the airflow is stabilized to a certain degree. Ideally, the dynamic pressure of the airflow in the air collecting cavity is completely dissipated, and the airflow can uniformly enter the downstream. But in reality, the size of the air collecting cavity is limited, the number of the air guide pipes in the circumferential direction is limited, and the air flow from the air guide pipes is in a jet state and cannot be completely dissipated; and the structures of turbine guide vanes, rectification blades and the like at the downstream of the gas collecting cavity are also discrete in the circumferential direction, and the number of the structures is generally larger than that of the air guide pipes, so that the blades facing the airflow feel impact, the flow of the entering cold air is larger, the pressure of the blades not facing the airflow is smaller, the flow of the cold air is smaller, and the temperature field of each blade in the circumferential direction is uneven due to the difference of the flow of the cold air, so that the blades and even the turbine casing deform unevenly. The related unevenness can cause the turbine blade rotor and stator to have a rub-impact condition, and the engine safety is influenced.

It is noted that the information disclosed in this background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information constitutes prior art already known to a person skilled in the art.

Disclosure of Invention

The embodiment of the invention provides a turbine blade cold air supply device and an aircraft engine, so that a turbine blade is cooled more uniformly.

According to an aspect of the present invention, there is provided a turbine blade cold air supply device including:

a gas collection cavity;

a plurality of turbine blades disposed downstream of the gas collection chamber;

the air guide pipe is communicated with the air collection cavity to convey cold air for cooling the turbine blades into the air collection cavity; and

and the rectifying device is arranged at the outlet of the bleed air pipe and is configured to enable the air flow flowing out of the bleed air pipe to be more uniform.

In some embodiments, the fairing includes a fairing panel with a plurality of through holes disposed therein.

In some embodiments, the plurality of through holes are radially distributed from the center of the rectifying plate to the outside, and the flow area of the through hole far away from the center of the rectifying plate is larger than that of the through hole near the center of the rectifying plate.

In some embodiments, the through holes comprise a first through hole having an axis collinear with the axis of the bleed air duct and a plurality of second through holes having an axis not collinear with the axis of the bleed air duct, the axes of the second through holes being inclined with respect to the axis of the bleed air duct in a direction away from the centre of the fairing.

In some embodiments, the axis of the second through hole distal from the first through hole is inclined to a greater extent than the axis of the second through hole proximal to the first through hole.

In some embodiments, the bleed air duct comprises a bleed air duct section and an extension duct section downstream of the bleed air duct section, the cross-axis cross-section of the extension duct section being trapezoidal, the axis of the second through-opening furthest from the first through-opening being parallel to the hypotenuse of the trapezoid.

In some embodiments, the distance between the two through holes is gradually reduced in a direction away from the center of the current plate.

In some embodiments, the bleed air duct comprises a bleed air duct section and an extension duct section downstream of the bleed air duct section, the fairing being arranged at an outlet of the extension duct section, the flow area of the outlet of the extension duct section being greater than the flow area of the outlet of the bleed air duct.

In some embodiments, the flow area of the elongated tube section increases gradually in the direction of airflow flow.

In some embodiments, the cross-section of the through-axis of the elongated tube section is trapezoidal, and the angle between the extensions of the two oblique sides of the trapezoid is 30 ° to 120 °.

In some embodiments, the extension tube section is disposed inside the gas collection chamber.

According to another aspect of the invention, an aircraft engine is provided, which comprises the turbine blade cold air supply device.

Based on the technical scheme, the rectifying device is arranged, so that the airflow flowing out of the air guide pipe is more uniform, the jet speed of the airflow can be reduced, each turbine blade is cooled more uniformly, local deformation of each turbine blade caused by nonuniform cooling is avoided, the condition of collision and abrasion between the rotor and the stator of each turbine blade is avoided, and the safety of the engine is improved.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the invention without limiting the invention. In the drawings:

FIG. 1 is a schematic view showing the structure of an embodiment of the turbine blade cold air supply apparatus according to the present invention.

FIG. 2 is a front view of an embodiment of the turbine blade cold air supply apparatus according to the present invention.

FIG. 3 is a partial schematic view of the turbine blade cold air supply device according to an embodiment of the present invention.

FIG. 4 is a schematic view showing a flow straightener in one embodiment of the turbine blade cold air supply apparatus of the present invention.

In the figure:

1. a gas collection cavity; 2. a turbine blade; 3. a bleed pipe; 31. a bleed air duct section; 32. extending the pipe section; 4. a rectifying device; 41. a through hole; 5. a mounting seat; 6. a casing.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments. It is to be understood that the described embodiments are merely a few embodiments of the invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the present invention without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it is to be understood that the terms "central," "lateral," "longitudinal," "front," "rear," "left," "right," "upper," "lower," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in the orientation or positional relationship indicated in the drawings for convenience in describing the invention and for simplicity in description, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting of the scope of the invention.

As shown in fig. 1, in one embodiment of the turbine blade cold air supply device provided by the present invention, the supply device comprises a gas collecting chamber 1, a gas introducing pipe 3, a rectifying device 4 and a plurality of turbine blades 2, the plurality of turbine blades 2 are arranged at the downstream of the gas collecting chamber 1, the gas introducing pipe 3 is communicated with the gas collecting chamber 1 to convey cold air for cooling the turbine blades 2 into the gas collecting chamber 1, the rectifying device 4 is arranged at the outlet of the gas introducing pipe 3, and the rectifying device 4 is configured to make the air flow flowing out of the gas introducing pipe 3 more uniform.

Through setting up fairing 4 for the air current that flows bleed pipe 3 is more even, and then makes each turbine blade 2 obtain more even cooling, also can reduce the jet velocity of air current, avoids each turbine blade 2 to lead to local deformation because of inhomogeneous cooling, and then avoids appearing bumping between 2 rotors of turbine blade and grinds the condition, improves the security of engine.

As shown in fig. 2, the gas collecting chamber 1 is an annular chamber disposed inside the engine and can be enclosed by a mounting base 5 and a casing 6. The air collecting cavity 1 collects air flow conveyed by the air guide pipe 3, the air flow enters the turbine blade 2 located at the downstream of the air collecting cavity 1 after being stabilized in the air collecting cavity 1 to cool the turbine blade 2, the turbine blade 2 is prevented from being deformed or damaged due to high-temperature impact, and the working safety of the engine is ensured.

The turbine blades 2 may be stationary blades such as guide blades or straightening blades, which do not rotate with the rotor of the turbine and thus cannot be uniformly cooled by the rotation of the blades, and the embodiment of the present invention may provide more uniform cooling of the blades by providing the straightening devices 4.

In some embodiments, the fairing 4 includes a fairing plate with a plurality of through holes 41 disposed therein.

The rectifying plate is of a flat plate structure, and the plurality of through holes 41 are formed in the rectifying plate, so that airflow can be prevented from flowing out in a strand, the area covered by the airflow when the airflow flows out is larger, and the uniformity of the flowing airflow is improved.

The cowling panel sets up in the export of bleed pipe 3, makes the gaseous through-hole 41 outflow in the bleed pipe 3 to reach the effect of rectification, make the air current of outflow more even, thereby make turbine blade 2 obtain more even cooling.

In some embodiments, the plurality of through holes 41 are uniformly arranged on the flow rectification plate, further improving the uniformity of the air flow.

As shown in fig. 4, in some embodiments, the plurality of through holes 41 are radially distributed from the center of the rectifying plate, and the flow area of the through hole 41 far from the center of the rectifying plate is larger than that of the through hole 41 near the center of the rectifying plate. The arrangement is consistent with the characteristic that the middle pressure presented by the outlet pressure of the bleed air pipe 3 is higher than the peripheral pressure, so that the airflow can be more easily diffused outwards along the radial direction, and the uniformity of the outflow airflow is realized.

In some embodiments, as shown in figure 3, the through holes 41 comprise a first through hole having an axis collinear with the axis of the bleed air duct 3 and a plurality of second through holes having an axis not collinear with the axis of the bleed air duct 3, the axis of the second through holes being inclined with respect to the axis of the bleed air duct 3 in a direction away from the centre of the fairing.

The first through hole is positioned in the center of the rectifying plate and is a through hole which is just opposite to the air guide pipe 3, and the axis of the through hole is collinear with the axis of the air guide pipe 3. Except the through hole facing the bleed air pipe 3, other through holes not facing the bleed air pipe 3 are second through holes, and the axis of the second through hole is inclined towards the direction far away from the center of the rectifying plate relative to the axis of the bleed air pipe 3, so that the purpose of setting is to enable the airflow to have the effect of obliquely and outwards flowing out when flowing out, the diffusion of the outflow airflow is more facilitated, the coverage range of the outflow is improved, the area of a single turbine blade 2 capable of being cooled is increased, or the number of the turbine blades 2 capable of being cooled is increased, and the cooling uniformity of the plurality of turbine blades 2 is realized.

In some embodiments, the axis of the second through hole distal from the first through hole is inclined to a greater extent than the axis of the second through hole proximal to the first through hole. The inclination degree of the second through hole gradually increases in a direction away from the center of the current plate.

The degree of inclination refers to the angle at which the axis of the second through hole is inclined relative to the axis of the bleed air duct 3, the angle between the axis of the second through hole and the axis of the bleed air duct 3 being greater the degree of inclination of the axis of the second through hole relative to the axis of the bleed air duct 3.

In some embodiments, the bleed air duct 3 comprises a bleed air duct section 31 and an extension duct section 32 downstream of the bleed air duct section 31, the fairing 4 is arranged at the outlet of the extension duct section 32, the cross-axis of the extension duct section 32 is trapezoidal in cross-section, and the axis of the second through-hole furthest from the first through-hole is parallel to the oblique side of the trapezoid. The advantage of setting up like this is, can make the air current that flows out along the second through-hole of the farthest distance from first through-hole that pastes the inner wall of extension pipe section 32, avoids the outflow direction of this part air current to change when the through-hole passes through, reduces the outflow resistance of this part air current, guarantees that the air current flows out along the place.

In some embodiments, the distance between the two through holes 41 gradually decreases in a direction away from the center of the current plate. This arrangement makes it possible to make the distance between the through holes 41 farther from the center of the rectifying plate smaller, and the through holes 41 are arranged more densely, enabling the air flow to flow out more easily at a position farther from the center of the rectifying plate.

In some embodiments, the bleed air duct 3 comprises a bleed air duct section 31 and an extension duct section 32 downstream of the bleed air duct section 31, the fairing 4 being arranged at an outlet of the extension duct section 32, the flow area of the outlet of the extension duct section 32 being greater than the flow area of the outlet of the bleed air duct 3.

By arranging the extension pipe section 32, the area which can be covered when the airflow flows out can be increased, and the cooling area is increased, so that the cooling airflow is more uniformly distributed to each turbine blade, and each turbine blade can be cooled; the extension pipe section 32 can also reduce the jet velocity, avoid direct impact on the turbine blades 2 facing the bleed air pipe 3, and is more favorable for dispersing the air flow along the radial direction, further increasing the cold air coverage area.

The bleed air pipe section 31 and the extension pipe section 32 can be two independent pipes and are connected in a threaded connection or a welding connection mode; the bleed duct section 31 and the extension duct section 32 may also be integrally formed.

In some embodiments, the flow area of the extension tube segment 32 gradually increases in the direction of airflow flow.

As shown in fig. 3, in some embodiments, the cross-section of the elongated tube section 32 is trapezoidal, and the extension line of two oblique sides of the trapezoid has an included angle α, which is 0 ° to 180 °, optionally 30 ° to 120 °, such as 30 °, 60 °, 90 °, or 120 °.

In some embodiments, the extension tube segment 32 is disposed inside the gas collection chamber 1. This facilitates the installation of the bleed air duct 3.

In the above-described embodiments, the number of turbine blades 2, bleed air ducts 3, fairings 4 and through holes 41 can be flexibly set.

Through the description of the embodiments of the turbine blade cold air supply device of the present invention, it can be seen that in the embodiments of the turbine blade cold air supply device of the present invention, the air flow enters the extension pipe section 32 from the air guiding pipe section 31, then enters the rectifying device 4, and enters the air collecting chamber 1 through the through hole 41. Due to the expanding effect of the extension tube segment 32, the jet velocity is greatly reduced; due to the flow guide effect of the through holes 41 on the rectifying device 4, the jet flow with lower speed radially diffuses into the gas collecting cavity 1, the cold air coverage area is increased, the cold air does not directly impact the turbine blades 2 which are right opposite to the air guide pipe 3 any more, the jet flow speed has larger component in the circumferential direction because the air flow diverges in the circumferential direction, the air flow in the gas collecting cavity 1 obtains the circumferential speed, and the air flow can be better conveyed to the turbine blades 2 which slightly deviate from the axis of the air guide pipe 3; the jet flow speed is reduced, so that dissipation is easier, the coverage area in the circumferential direction is increased, and the circumferential conveying effect is improved; meanwhile, the flow area of the second through hole is gradually increased in the direction far away from the center of the rectifying plate, so that the characteristic that the central pressure of the jet flow at the outlet of the bleed air pipe 3 is high and the peripheral pressure is low is adapted, the cooling flow uniformity of the turbine blade 2 is further improved, the uniformity of a temperature field and deformation is further improved, and the consequences of rotor and stator collision and abrasion and the like caused by non-uniform deformation due to non-uniform cooling are prevented.

The embodiment of the invention eliminates the impact on the turbine blades 2 facing the air guide pipe 3, greatly improves the air inlet pressure of the turbine blades 2 which are deviated from the axis of the air guide pipe 3, eliminates the condition that the cold air flow of the turbine blades 2 facing the air guide pipe 3 is obviously higher than that of other blades due to the impact effect of radial jet flow at the outlet of the air guide pipe 3, reduces the circumferential cooling nonuniformity, and can also relieve the corresponding circumferential deformation nonuniformity of the casing.

The structure of an embodiment of the turbine blade cool air supply device of the present invention will be described in detail with reference to the accompanying drawings 1 to 4:

as shown in fig. 1 and 2, the turbine blade cold air supply device comprises a gas collecting cavity 1, turbine blades 2, a bleed air pipe 3 and a rectifying device 4, wherein the gas collecting cavity 1 is an annular cavity and is enclosed by a mounting seat 5 and a casing 6. The turbine blades 2 are arranged at the downstream of the gas collecting cavity 1, and the gas guide pipe 3 guides cooling gas from the compressor to the gas collecting cavity 1. The bleed air duct 3 comprises a bleed air duct section 31 and an extension duct section 32, the extension duct section 32 being connected downstream of the bleed air duct section 31. The extension pipe section 32 is in a flaring shape, the cross section of the axial line of the extension pipe section is in an isosceles trapezoid shape, the extension lines of the two waists are intersected, and the included angle alpha is 60 degrees.

As shown in fig. 1, 12 turbine blades 2 are uniformly arranged in the circumferential direction, 4 bleed air ducts 3 are also uniformly arranged in the circumferential direction, each bleed air duct 3 faces one turbine blade 2, and each extension duct section 32 can cover 3 turbine blades 2 by providing the extension duct section 32 in a flared shape.

As shown in fig. 3, the rectifying device 4 includes a rectifying plate provided at the outlet of the extension pipe section 32.

As shown in fig. 4, the rectifying plate is provided with a plurality of through holes 41, and the plurality of through holes 41 are radially distributed in a direction away from the center of the rectifying plate. The plurality of through holes 41 include a first through hole located at the very center of the current plate, which is collinear with the axis of the extension pipe section 32. The plurality of through-holes 41 further includes a plurality of second through-holes, and the through-holes 41 that are not collinear with the axis of the extension pipe section 32 are all second through-holes.

The cowling panel is the circular slab, uses the centre of a circle of first through-hole as the center, and a plurality of second through-holes arrange the annularity, 5 rings totally. The first through hole and the second through hole are round holes. Each ring comprises 20 second through holes, the diameters of the second through holes in each ring are the same, the diameters of the second through holes in each ring from inside to outside are gradually increased, and the radial distance between the two rings is gradually reduced from inside to outside.

The second through holes in different rings extend outwards along the same radius. As shown in fig. 3, the axis of the second through hole is arranged obliquely with respect to the axis of the first through hole, and the degree of inclination of the axis of the second through hole gradually increases from the inside to the outside. The axis of the second through hole farthest from the first through hole is parallel to the waist of the trapezoidal section. On the same diameter, the second through holes positioned at two sides of the first through hole are symmetrically arranged.

Based on the turbine blade cold air supply device in each embodiment, the invention also provides an aircraft engine which comprises the turbine blade cold air supply device.

The positive technical effects of the turbine blade cold air supply device in the above embodiments are also applicable to aircraft engines, and are not described herein again.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention and not to limit it; although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art will understand that: modifications to the specific embodiments of the invention or equivalent substitutions for parts of the technical features may be made without departing from the principles of the invention, and these modifications and equivalents are intended to be included within the scope of the claims.

Claims

1. A turbine blade chilled air supply, comprising:

a gas collection chamber (1);

a plurality of turbine blades (2) arranged downstream of the gas collection chamber (1);

a gas guide pipe (3) communicated with the gas collecting cavity (1) to convey cold air for cooling the turbine blades (2) into the gas collecting cavity (1); and

a fairing (4) arranged at the outlet of the bleed air duct (3) and configured to make the air flow out of the bleed air duct (3) more uniform.

2. The turbine blade cold air supply device according to claim 1, wherein said fairing means (4) comprises a fairing plate provided with a plurality of through holes (41).

3. The cool air supply device for turbine blades as claimed in claim 2, wherein a plurality of said through holes (41) are radially distributed from the center of said flow rectification plate, and the flow area of said through holes (41) far from the center of said flow rectification plate is larger than the flow area of said through holes (41) near the center of said flow rectification plate.

4. The turbine blade cold air supply device according to claim 2, wherein the through-holes (41) include a first through-hole whose axis is collinear with the axis of the bleed air duct (3) and a plurality of second through-holes whose axis is not collinear with the axis of the bleed air duct (3), the axis of the second through-holes being inclined with respect to the axis of the bleed air duct (3) in a direction away from the center of the cowling panel.

5. The turbine blade cold air supply device according to claim 4, wherein an axis of said second through hole distant from said first through hole is inclined more than an axis of said second through hole close to said first through hole.

6. The turbine blade cold air supply device according to claim 4, characterized in that the bleed air duct (3) comprises a bleed air duct section (31) and an extension duct section (32) downstream of the bleed air duct section (31), the cross-axis of the extension duct section (32) being trapezoidal in cross-section, the axis of the second through-hole furthest from the first through-hole and the oblique side of the trapezoid being parallel to each other.

7. The turbine blade cold air supply device according to claim 2, wherein a distance between two of said through holes (41) is gradually decreased in a direction away from a center of said flow rectification plate.

8. The turbine blade cold air supply device according to claim 1, characterized in that the bleed air duct (3) comprises a bleed air duct section (31) and an extension duct section (32) downstream of the bleed air duct section (31), the fairing (4) being arranged at the outlet of the extension duct section (32), the flow area of the outlet of the extension duct section (32) being larger than the flow area of the outlet of the bleed air duct (3).

9. The turbine blade cold air supply device according to claim 8, wherein the flow area of said extension pipe section (32) is gradually increased in the flow direction of the air flow.

10. The cool air supply apparatus for turbine blades as claimed in claim 8, wherein the cross-sectional plane of the axis of the extension pipe section (32) is a trapezoid, and the angle of extension of the oblique sides of the trapezoid is 30-120 °.

11. The turbine blade cold air supply device according to claim 8, characterized in that the extension pipe section (32) is arranged inside the air collecting chamber (1).

12. An aircraft engine, characterized in that it comprises a turbine blade cool air supply device according to any one of claims 1 to 11.