RU2716097C1 - Turbine working blade of gas turbine engine and gas turbine engine - Google Patents

Abstract

FIELD: engine building.

SUBSTANCE: working blade of gas-turbine engine has hollow profile with convex and concave thin walls, between which there is a power rod, cooling intensifiers, to which coolant is supplied, and shank. Power rod is connected with shank. Profile is divided into two parts, of which root part is made integral with shank, and peripheral part is integral with power rod. Cooling intensifiers arranged between the inner walls of the profile and the power rod are made in the form of a vortex matrix. In the peripheral part of the profile the ribs of the vortex matrix are in contact, and in the root part of the profile they are located at a distance from each other.

EFFECT: invention is aimed at improvement of gas turbine engine efficiency and improvement of cooling efficiency of turbine working blades.

3 cl, 3 dwg

Description

The invention relates to the field of gas turbine engines and can be used in aircraft gas turbine engines, as well as in power gas turbine units.

The history of the creation and development of economical gas turbine engines and gas turbine power plants is associated with the search for solutions to improve the efficiency of the thermodynamic cycle. The efficiency of the thermodynamic cycle depends primarily on the parameters of the thermodynamic cycle and, in particular, on the gas temperature in front of the turbine. The higher the gas temperature in front of the turbine, the higher the efficiency of the thermodynamic cycle. Moreover, the possibility of achieving a high gas temperature in front of the turbine is limited by the design features of the engine turbine, a critical element of which are the turbine blades.

The turbine blades experience high loads in the field of centrifugal forces and are one of the most loaded elements of gas turbine engines. In addition, the turbine blades of a gas turbine engine are affected by the flow of hot gases. The combination of these factors leads to the need to improve the design of turbines and their working blades when creating new modifications of gas turbine engines.

A known blade of a turbomachine (RU 2118462) comprising a lock, a feather, an inner shelf, a peripheral shelf, short super shells connected to them with local fastening or resting on a shelf of each short super shell only in the region of its peripheral section. Alternatively, the super shell in thickness is made composite in the form of a package of predominantly metallic mini shells inserted one into another with local fastening or resting on a shelf along the perimeter of the feather of each mini shell only in the zone of its peripheral section. As an option, the super shell contains sliding side supports in the form of discrete protrusions on its inner surface. Alternatively, at least one mini-shell and pen have protective coatings on their surfaces.

Known taken as a prototype, a cooled working turbine blade, consisting of a shank, a working profile part, having a hollow profile with convex and concave thin walls, between which there is a power rod made integrally with the shank and cooling intensifiers, characterized in that the working profile part is made divided into two parts, of which the basal part is made in one piece with the shank, and the peripheral part in one piece with the power rod (RU 2656052).

The disadvantage of these blades is their vulnerability to centrifugal forces and high temperatures, which does not allow increasing the gas temperature in front of the turbine.

The proposed solution is aimed at eliminating these drawbacks, namely, providing the possibility of increasing the efficiency of the gas turbine engine by increasing the gas temperature in front of the turbine, which is ensured by the design of the working blades providing a rational redistribution of stresses in the working blades of the turbine and the simultaneous use of an effective cooling system for the working blades of the turbine.

The use of a relatively cold power rod in the internal cavity of the profile part of the cooled turbine blade, made integrally with the blade shaft and of a special design made in the form of a vortex matrix of cooling intensifiers between the inner walls of the profile and the power rod, allows you to redistribute the loads from the elements of the blade in the field of centrifugal forces and enhance cooling of the blades, which helps to increase the bearing capacity of the turbine blades.

According to the invention, in the inner cavity of the profile part of the cooled turbine blade, a relatively cold power rod is located integrally with the shank of the blade, and the profile of the blade is divided into peripheral and root zones. Moreover, in the peripheral zone of the inner cavity of the profile part of the turbine blade, a mechanical connection is made between the profile and the power rod (for example, elements of cooling intensifiers located on the inner wall of the profile and on the power rod connect the profile part to the power rod and the edges of the vortex matrix located on the inside the profile wall and on the power rod are in contact (intersect, turning into a single whole), and in the root zone of the internal cavity of the profile part of the working blade of the fur turbine There is no physical connection between the profile and the force rod, and the edges of the vortex matrix do not touch each other (they cross, allowing mutual displacement).

This design of the turbine working blade allows unloading the power rod from the load in the field of centrifugal forces, since only the peripheral part of the profile part of the working blade is connected to the power rod (only the load from it can be transferred to the power rod, since the edges of the vortex matrix in this zone intersect, and through them load is transferred from the peripheral part of the profile). In this case, the root section of the profile part of the working blade is also unloaded, since the basal part of the profile of the working blade is connected directly to the shank of the working blade of the turbine, and the power rod carries the load from the peripheral part. In this case, the power rod is connected or integral with the blade lock or with the turbine disk, which, in the end, receives the forces from the turbine blades. The proposed constructive solution allows, ceteris paribus, to reduce the overall level of stress-strain state of the turbine blades.

The proposed solution is illustrated by the following figures:

FIG. 1 - engine;

FIG. 2 - turbine;

FIG. 3 - turbine blade;

where

1 - turbine;

2 - working blade;

3 - basal part of the profile;

4 - peripheral part of the profile;

5 - edges of the vortex matrix;

6 - shank of the working blade;

7 - power rod.

During the operation of the gas turbine engine, the parameters of the working fluid (temperature and pressure) when moving along the flow part change in accordance with the features of the thermodynamic cycle that is implemented in this engine. In this case, the working fluid is compressed, heated, and then expanded, doing useful work. The engine efficiency, first of all, depends on the efficiency of the thermodynamic cycle, and the possibility of increasing the efficiency of the thermodynamic cycle depends, in particular, on the possibility of increasing the gas temperature in front of the turbine.

Turbine 1 is under constant exposure to gas having a high temperature. One of the main elements that determine the reliability and efficiency of the turbine and the engine as a whole is the turbine blade 2. Thus, the ability of the turbine blades to work in these conditions determines the efficiency of the gas turbine engine.

When flowing around the profile of a turbine blade, an aerodynamic force is generated, which in turn creates torque on the turbine shaft. In this case, the heat flux from the working fluid heats the structural elements of the blade. At the same time, centrifugal forces act on the structural elements of the blade. Based on the foregoing, there is a need to ensure the health of the blades in conditions of a high level of stress from centrifugal forces and at high temperature.

The full load from the centrifugal forces acting on the basal part 3 of the profile of the working blade 2 is directly perceived by the shank 6, since the ribs 5 of the vortex matrix in this zone intersect (do not touch) and the load is not transmitted through them to the power rod 7. Moreover, the stress state in this part of the profile is significantly reduced due to shortening compared with the full height of the profile part of the blade. The full load from the centrifugal forces acting on the peripheral part 4 of the profile of the working blade 2 is perceived by the power rod 7, since the ribs 5 of the vortex matrix in this zone intersect (contact) and through them the load is transmitted to the power rod 7. In this case, the stress state of each of the two parts working profile part (basal part 3 of the profile and the peripheral part 4 of the profile) is significantly reduced by reducing the height of each of them compared to the full height of the working profile of the scapula.

The level of permissible stresses in the material depends on the temperature of the material in a particular place. Moreover, the higher the temperature of the material, the lower the level of permissible stresses in the material. And vice versa: the lower the stress level in the material, the higher the temperature level of the material, which can be allowed to work at such stresses in the material. Given the proposed solution, it becomes possible to raise the gas temperature in front of the turbine. With increasing gas temperature in front of the turbine, the efficiency of the thermodynamic cycle and the efficiency of the gas turbine engine as a whole increase.

Thus, by reducing the stress state of each of the two parts of the divided working profile of the turbine blade, it is possible to increase the gas temperature in front of the turbine and thereby increase the efficiency of the thermodynamic cycle and engine efficiency.

Claims (3)

1. The working blade of a gas turbine engine having a hollow profile with convex and concave thin walls, between which there is a power rod, cooling intensifiers, on which the cooling medium is supplied, and a shank, the power rod being connected to the shank, and the profile is divided into two parts, of which the basal part is made in one piece with the shank, and the peripheral part in one piece with the power rod, characterized in that the intenses located between the inner walls of the profile and the power rod cooling coefficients are made in the form of a vortex matrix, and in the peripheral part of the profile the edges of the vortex matrix are in contact, and in the basal part of the profile are located at a distance from each other. 2. The turbine blade of claim 1, characterized in that the profile is made without a transverse section between the basal part and the peripheral part of the profile. 3. Gas turbine engine with a high-temperature cooled gas turbine, characterized in that the gas turbine of the engine contains working blades according to claim 1.

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