RU2534672C1 - High-temperature turbine rotor - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: high-temperature turbine rotor comprises disks of the first and second stages between which an intermediate disk with radial protrusions is mounted. The intermediate disk is fixed by radial protrusions in the circumferential direction in relation to the axial protrusions set on the first stage disk body. The axial protrusions on the first stage disk body are made so that to form an U-shaped protrusion in the cross-section. The circumferential rib of the intermediate disk placed on the inner side of the first stage disk rim is provided with grooves. The said grooves serve to connect the air cavities of increased pressure to the annular air cavity of decreased pressure which is limited by the circumferential rib of the intermediate disk, radial protrusions of the intermediate disk, the U-shaped protrusion and the first stage disk body. The relation of the U-shaped protrusion in the axial direction to the depth of the U-shaped protrusion groove accounts for 1.1-2.

EFFECT: invention allows for higher reliability and reduced weight of a high-temperature turbine rotor.

3 dwg

Description

The invention relates to rotors of high temperature turbines of gas turbine engines of aviation and ground applications.

A rotor of a high-temperature turbine is known, the intermediate disks of which are fixed in the circumferential direction relative to the flanges fixed to the shaft with the help of protrusions made on the hubs of the intermediate disks (Patent RU 2261350, F02C 7/12, F02C 7/06, 09/27/2005).

The disadvantage of this design is its low reliability, since the protrusions made on the hub of the intermediate disks are stress concentrators.

Closest to the claimed is the rotor of a high-temperature turbine, including disks of the first and second stages, between which there is an intermediate disk with radial protrusions that fix the intermediate disk in the circumferential direction relative to the axial protrusions located on the canvas of the disk of the first stage (Patent US 7905083, F02K 3/02 March 15, 2011).

A disadvantage of the known design adopted as a prototype is its low reliability due to the increased temperature of the radial protrusions of the intermediate disk and axial protrusions located on the disk web of the first stage.

The technical result of the claimed invention is to increase the reliability and reduce the weight of the rotor of a high-temperature turbine by organizing effective cooling of the radial protrusions of the intermediate disk and the axial protrusions of the first-stage disk.

, где:The specified technical result is achieved by the fact that in the rotor of the high-temperature turbine, including the disks of the first and second stages, between which there is an intermediate disk with radial protrusions that fix the intermediate disk in the circumferential direction relative to the axial protrusions located on the disk sheet of the first stage, axial protrusions on the disk sheet the first stage is made in such a way that form in cross section a U-shaped protrusion, and the annular rib of the intermediate disk, located on the inner side of the rim the disk of the first stage, made with grooves communicating the air cavity of the increased pressure under the lock of the working blade of the first stage with the annular air cavity of the reduced pressure limited by the annular edge of the intermediate disk, the radial protrusions of the intermediate disk, the U-shaped protrusion and the canvas of the disk of the first stage, the shaped protrusion is made in compliance with the ratio $$\frac{H}{h}=\mathrm{1,1}-2$$

where:

H is the length of the U-shaped protrusion in the axial direction;

h is the depth of the groove of the U-shaped protrusion.

The execution on the axial annular edge of the intermediate disk, located on the inner side of the rim of the first stage disk, of grooves connecting the air of increased pressure under the lock of the working blade of the first stage with the ring air cavity of reduced pressure, limited by the annular edge of the intermediate disk, the radial protrusions of the intermediate disk, the disk blade the first stage and the U-shaped protrusion (formed by axial protrusions on the canvas of the disk of the first stage), allows you to organize the cooling of axial and radial nyh protrusions air flow from the air cavities under high pressure locks of rotor blades in the first stage low pressure cavity between the first stage disk and the disk of the second stage. In high-temperature turbine rotors, to improve the efficiency, high pressure cooling air is used to cool the first stage rotor blades, and “cheaper” low pressure air behind the intermediate stage of the compressor is used to pressurize the interdisc cavity, to cool the intermediate disk and to cool the second stage rotor blades , which allows us to use this air pressure difference for additional cooling of the rim and the blade web of the first stage with axial protrusions and the rim intermediate disc with radial protrusions.

Improving the cooling of axial and radial protrusions allows, in connection with an increase in the strength of materials, to reduce the number of axial and radial protrusions, which reduces the weight of the turbine rotor.

The execution of the axial protrusions on the canvas of the disk of the first stage with the formation in cross section of a U-shaped protrusion allows you to reduce the total number of protrusions on the canvas of the disk, which reduces weight, secures the fixing of the intermediate disk in the circumferential direction both in the throttle response and gas discharge modes, and It also improves the reliability of the turbine rotor by reducing the stress concentration by increasing the radii at the transition from the U-shaped protrusion to the disk web.

обусловлен тем, что при $$\frac{H}{h}<\mathrm{1,1}$$

ухудшается надежность ротора высокотемпературной турбины вследствие повышения концентрации напряжений, а при $$\frac{H}{h}>2$$

увеличивается вес диска и ротора турбины.Ratio selection $$\frac{H}{h}$$

due to the fact that when $$\frac{H}{h}<\mathrm{1,1}$$

the reliability of the rotor of a high-temperature turbine deteriorates due to increased stress concentration, and when $$\frac{H}{h}>2$$

increases the weight of the disk and rotor of the turbine.

Figure 1 shows a longitudinal section of the rotor of a high-temperature turbine, figure 2 - element I from figure 1 in an enlarged view, figure 3 shows a section aa from figure 2 in an enlarged view.

The rotor 1 of the high-temperature turbine includes a disk 2 of the first stage 2 and a disk 3 of the second stage, interconnected by a bolt connection 4.

An intermediate disk 6 is installed in the interdisc space 5 of the reduced pressure, which fixes in the axial direction by the rim 7 of the lock 8 the working blade 9 of the first stage and the lock 10 of the working blade 11 of the second stage.

On the rim 7 of the intermediate disk 6 there is made an axial annular rib 13 located on the inside of the rim 12 of the disk 2 of the first stage, on which grooves 14 are made connecting the air cavities 15 of the increased pressure under the locks 8 of the working blades 9 of the first stage with the ring air cavity 16 of the reduced pressure bounded by an annular axial rib 13, radial protrusions 17 located on the rim 7 of the intermediate disk 6, the web 18 of the disk of the first stage with paired axial protrusions 19 and 20, forming together a U-shaped in cross section, the protrusion 21.

The cavity 16 of the reduced pressure at the outlet is connected to the interdisc cavity 5 of the reduced pressure.

The radial protrusions 17 of the intermediate disk 6 are located in the groove 22 between the axial protrusions 19 and 20, which makes it possible to fix the intermediate disk 6 in the circumferential direction both in the throttle response modes and in the gas discharge modes.

The increased value of the radius R of the transition from the blade 18 of the disk 2 to the axial protrusions 19 and 20 reduces the stress concentration, and the groove 22 between the protrusions 19 and 20 is made of reduced depth, which eliminates the effect of the reduced radius r at the bottom 23 of the groove 22 on the stress concentration.

Position 24 denotes a stream of reduced pressure air entering the cavity 5 due to the intermediate stage of the compressor (not shown in the drawings).

Position 25 indicates the flow of cooling air from the cavities 15 of the increased pressure into the interdisc cavity 5 of the reduced pressure.

This device works as follows.

During operation of the rotor 1 of the high-temperature turbine, the air stream 25 cools the protrusion U-shaped in cross section of the protrusion 21 of the disk 2 of the first stage, the radial projections 17, the web 18 of the disk 2 of the first stage from the side of the intermediate disk 6, as well as the intermediate disk 6 itself.

Claims (1)

A rotor of a high-temperature turbine, comprising first and second stage disks, between which an intermediate disk with radial protrusions is located, fixing the intermediate disk in a circumferential direction relative to axial protrusions located on the first stage disk web, characterized in that the axial protrusions on the first stage disk web are made in such a way that they form a U-shaped protrusion in cross section, and the annular rib of the intermediate disk, located on the inside of the rim of the disk of the first stage, is made with basics, informs air pressurized cavity locked rotor blade of the first stage with the annular air cavity of reduced pressure, a limited annular intermediate disc edge, radial projections of the intermediate disk, U-shaped projection and blade disc of the first stage, the U-shaped protrusion is in compliance with the relation

where:
H is the length of the U-shaped protrusion in the axial direction;
h is the depth of the groove of the U-shaped protrusion.

Images