Abradable device on the blower casing of a gas turbine engine

Abstract

The invention concerns a turbine engine with an axis of rotation B comprising a blower casing (10) and a blower (V) with movable blades (17). A clearance lies between the internal surface of the casing and the free ends of the blades. A bearing of the blower is connected to fixed parts of the turbine engine by connections such that, in the event of a load on the blower blades, these connections break and the axis of rotation of the blower oscillates about the axis of rotation B. The casing comprises, bonded to its internal surface and over at least part of the extent of the clearance, a layer of thermoformable foam (19) placed opposite the ends of the blades (17) of the blower (V). The layer of thermoformable foam (19) is partly covered with a layer of abradable substance (14), the thickness of the layer of abradable substance (14) is such that the free ends of the blades of the blower do not reach the layer of foam during the normal functioning of the turbine engine, and, in the event of a load on the blower, the free ends of the blades at least partly fragment the layer of abradable substance.

Description

FIELD OF THE INVENTION [0001] The invention concerns the field of gas turbine engines, and more particularly gas turbine engine blower casings. BACKGROUND OF THE INVENTION [0002] In the case of aircraft engines, a bladed blower disc is situated on the rotor part at the inlet to the engine and precedes the bladed discs of the compressor. This bladed blower disc accelerates the air before entering the compressor stages. This bladed blower disc is liable to receive foreign bodies such as ice, birds or others. Because of this, this bladed disc is liable to deform, to cause an imbalance on the blower support shaft and cyclic loads and vibrations communicated by the blower shaft support bearings to the fixed parts of the turbine engine, to which these support bearings are connected. [0003] To prevent communication of these loads and vibrations, it is known from the application FR 2 752 024 how to fit a so-called “fusible” bearing, that is to say the bearing supporting the blower shaft is ...

AI Technical Summary

Benefits of technology

[0005] The present invention

Problems solved by technology

This bladed blower disc is liable to receive foreign bodies such as ice, birds or others.

Because of this, this bladed disc is liable to deform, to cause an imbalance on the blower support shaft and cyclic loads and vibrations communicated by the blower shaft support bearings to the fixed parts of the turbine engine, to which these support bearings are connected.

However, the axis of rotation of the bladed disc of the blower oscillates about the fixed axis of rotation of the turbine engine.

This oscillation causes that of the blades, which then violently touch the blower casing.

The latter is thus greatly stressed mechanically, or even torn, during these shocks.

Such a technology is expensive and repairs must be carried out in specialist workshops, particularly in the case of casings with a specific shape, for example conical.

Images