Compressor blade root for engine blades of aircraft engines

Abstract

On a compressor blade (1) for gas turbine engines which is made of a fiber-composite core (4) with metallic enclosure (5) and which comprises a blade root (3) connected to an airfoil (2) and held in a recess (9) of a compressor disk (10), the fiber-composite core is made of transversely compressed fibers with subsequent matrix infiltration and is intimately connected via a surface enlargement by a micro-structure (7) to inner surfaces of the enclosure (5). Thus, the forces are introduced into the blade root (3) directly via the fiber material. Opposite side faces of the longitudinally straight blade root (3) each feature circularly arched bearing faces (8) with different centers (M1, M2) which mate with similarly arched bearing areas (11) provided in the recess (9) to provide for a limited, dampened pendular movement for the absorption of the bending forces acting upon the fiber-composite core.

Description

[0001] This application claims priority to German Patent Application DE10326719.0 filed Jun. 6, 2004, the entirety of which is incorporated by reference herein. BACKGROUND OF THE INVENTION [0002] This invention relates to a compressor blade root for engine blades of aircraft engines which comprise a fiber-composite core with metallic enclosure and which is held in a recess of a compressor disk. [0003] In order to save weight, the fan blades (compressor blades) of gas turbine engines are, as is generally known, made of fiber-reinforced plastic with a metallic enclosure. The blade is firmly attached via a dovetail-style, longitudinally curved blade root in a conformal recess of the compressor disk (rotor). Centrifugal forces, gas pressure and vibrations of the airfoil excited by the flow medium subject the compressor blades of turbomachines to considerable stresses which, in the case of aircraft engines, can become excessive in the event of a bird strike, i.e. an impingement of a bird...

AI Technical Summary

Benefits of technology

[0007] It is a broad aspect of the present invention to provide an engine blade whose compressor blade root features a fiber-composite core and a metallic enclosure such that the blade is capable of taking up and transferring high forces while having a long service life.

[0010] This fiber-composite core enables, on the one hand, high forces to be taken up and transferred to the enclosure in the area of the blade root, i.e. introduced in the metallic part of the blade root. On the other hand, the bending load of the fiber material is reduced by the frictionally dampened pendular movement of the blade root allowed within a limited range in the recess of the compressor disk.

[0011] A compressor blade featuring such a compressor blade root is very light, which is favorable for the operation of the gas turbine engine. Such a compressor blade is nevertheless capable of withstanding and transferring, without damage, the high forces to which it is exposed. It has high dynamic strength and fatigue stability, as well as a long service life. Stress and wear in the recess locating the blade root are reduced.

Problems solved by technology

Since this design of a fiber-composite core is not capable of withstanding high bending loads, it is pendularly located within a limited angular range and frictionally dampened in the recess for the location of the blade root in the compressor disk.

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