RU2241842C1 - Turbine rotor support of gas-turbine engine - Google Patents

Abstract

FIELD: aircraft engine manufacturing.

SUBSTANCE: invention relates to devices used to support turbine of gas-turbine engines of flying vehicles. Proposed support of turbine of gas-turbine engine has turbine housing 1, bearing housing 2 and bracing rods 3 connecting housings 1 and 2. Rods 3 pass through inner spaces of nozzle blades 4. One rod or pair of bracing rods 3 can pass through inner space of one nozzle blade. Longitudinal axes 5 of bracing rods are tilter relative to cross section of support, axes 5 in each pair of adjacent rods being tilted in different directions. Thanks to such tilting, rods 3 in each pair either form or intersect in plane. Flexible members 6 are installed on rods 3. Invention improves reliability of supports of gas-turbine engines owing to taking up axial loads, appearing on engine at changes of aircraft altitudes, by support members and elimination of temperature stresses on support members.

EFFECT: improved reliability of turbine rotor supports.

5 cl, 1 dwg

Description

The invention relates to the field of aircraft engine manufacturing, and in particular to support devices for turbines of gas turbine engines, designed primarily for aircraft (hereinafter referred to as L.A.).

A known support of a turbine of a gas turbine engine (GTE), comprising a bearing housing connected to the power housing of the turbine by tie rods passing through the internal cavities of the blades of the nozzle apparatus (1).

A known support is located in front of the impeller of a high pressure turbine, and the axial loads in it are perceived by a support cone mounted on the bearing housing and the combustion chamber. However, when the turbine support is located in the space between the impellers of the high and low pressure turbines, this design of the support, due to the limited axial space, is practically not feasible, and in most design schemes of two-rotor engines, especially those with a high pressure turbine impeller cooling system, the turbine support is located It is in the interdisc space. At the same time, for engines used for HP, in contrast to engines for stationary gas turbine installations, the support perception arising during the evolution of HP axial loads are imperative.

In addition, when switching from one engine operation mode to another, the temperature of the elements of the outer turbine housing and the bearing housing is different, which results in radial deformations of these elements, which, when they are rigidly attached to each other, lead to the appearance of temperature stresses. This can lead to the destruction of the support elements and, thereby, reduces the reliability of its work.

The objective of the claimed invention is to increase the reliability of a turbine engine support, by ensuring that the support elements perceive axial loads and torque from the support plane arising on the engine during the evolution of the aircraft, as well as eliminate temperature stresses arising in the support elements.

The technical result is achieved by the fact that in the support of the turbine rotor of a gas turbine engine, comprising a bearing housing connected to the power housing of the turbine by connecting rods passing through the internal cavities of the nozzle vanes, the longitudinal axis of the connecting rods are inclined relative to the plane of the cross section of the support, and the inclination of each pair of adjacent rods relative to this plane is directed in different directions.

In addition, the following may occur in the turbine rotor support of a gas turbine engine:

- the joints of each pair of adjacent tie rods with the turbine power housing are offset relative to each other in the longitudinal direction;

- the joints of each pair of adjacent tie rods with the bearing housing are offset relative to each other in the longitudinal direction;

- a couple of tie rods passes through the internal cavity of one blade of the nozzle apparatus;

- elastic elements are installed on the tie rods.

The inclination of each pair of tie rods in different directions relative to the plane of the cross-section of the support ensures the presence of an angle between the power elements in each pair of adjacent rods and, thereby, forms a power structure that accepts axial loads.

In one of the special cases of the support, when the joints of each pair of adjacent tie rods with the turbine power housing are displaced relative to each other in the longitudinal direction, each pair of power elements forms a power triangle in the plane with an apex located on the bearing housing in the bearing cross section.

Simultaneous longitudinal relative displacements of the joints of each pair of adjacent tie rods with the bearing housing and the joints of each pair of adjacent tie rods with the turbine power housing ensures that the rods intersect in the plane, which allows the power rods to be placed in a more limited space allocated for the support, while maintaining the presence of a given angle between the longitudinal axes of adjacent rods.

The passage of two tie rods through the internal cavity of one nozzle blade allows to use twice the number of power elements in the connection of the turbine housing with the bearing housing, thereby increasing the reliability of the support.

The installation of elastic elements on the tie rods makes it possible to compensate for the radial displacements of the bearing housing relative to the turbine power housing resulting from different temperatures of their heating, thereby reducing temperature stresses on stationary and, in particular, variable engine operating modes, which also increases reliability support work.

The invention is illustrated graphically, where the drawing shows a General view of the support of the turbine.

A turbine support of a gas turbine engine comprises a turbine power housing 1, a bearing housing 2, and tie rods 3 connecting the housings 1 and 2. The rods 3 pass through the internal cavities of the nozzle vanes 4. One or a pair of tie rods 3 can pass through the internal cavity of one nozzle blade 4. The longitudinal axis 5 of the tie rods are inclined relative to the cross-section of the support, and in each pair of adjacent rods, the axis 5 is inclined in different directions. As a result of this tilt, the rods 3 in each pair form an angle in the plane or cross. On the rods 3, for example, in the place of their attachment to the housing 1, elastic elements 6 are installed, which can be made, for example, in the form of Belleville springs.

The work of the support is as follows.

In the process of engine operation, the radial load acting on the support is perceived due to the fact that one half of the rods 3 is stretched and the other half is compressed, while the force along the rods is distributed according to the law of cosine.

Due to the location of the tie rods in the support at an angle relative to each other, each pair of adjacent rods forms a force triangle in the plane. In this triangle, when an axial force is applied to the support, one of the rods works in compression and the other in tension, resulting in a reactive force in the triangle. The sum of the axial components of the reactive forces arising in each pair of rods is equal in magnitude to the effective axial load. Thus, the support perceives axial load.

In addition, in most designs of known engines with a rotor bearing, the bearing is located with the offset relative to the middle section of the bearing, which leads to the appearance of a bending moment from the plane of the bearing, which during the evolution of L. has a significant value. This moment is converted into a pair of axial forces, which are perceived by the support as perceived axial load.

The mutual radial displacement of the housings 1 and 2, which occurs during transient engine operation due to the difference in temperature, is compensated by a change in the length of the elastic elements 6, and the tension of the rods 3, tightening the housings 1 and 2, is selected so that any temperature gradient between the housings 1 and 2 did not lead to a relaxation of the junction of the rods 3 with these bodies.

The invention improves the reliability of the support of a turbine engine turbine, due to the perception by the support elements of axial loads that occur on the engine during the evolution of the aircraft, as well as by compensating for the radial movement of the bearing housing relative to the power housing of the turbine.

Sources of information

UK patent No. 2229229A, IPC 7 F 02 C 7/06, 1990

Claims (5)

1. The support of the turbine rotor of a gas turbine engine, comprising a bearing housing connected to the power housing of the turbine by connecting rods passing through the internal cavities of the blades of the nozzle apparatus, characterized in that the longitudinal axes of the connecting rods are inclined relative to the plane of the cross section of the support, and the inclination of each pair of adjacent rods relative to this plane is directed in different directions. 2. The support of the turbine rotor of a gas turbine engine according to claim 1, characterized in that the joints of each pair of adjacent coupling rods with the turbine power housing are offset relative to each other in the longitudinal direction. 3. The support of the rotor of the turbine of a gas turbine engine according to claim 1 or 2, characterized in that the connection points of each pair of adjacent coupling rods with the bearing housing are offset relative to each other in the longitudinal direction. 4. The support of the turbine rotor of a gas turbine engine according to claim 1, characterized in that a pair of tie rods passes through the internal cavity of one blade of the nozzle apparatus. 5. The support of the rotor of the turbine of a gas turbine engine according to claim 1, characterized in that elastic elements are installed on the tie rods.