Aeroelasticity Analysis of Rotor Blades in the First Two Stages of Axial Compressor in the Case of a Bird Strike

A bird strike can cause damage to stationary and rotating aircraft engine parts, especially the engine fan. This paper presents a bird strike simulated by blocking four stator blade passages. It includes the numerical results of the unsteady lowfrequency aerodynamic forces and the aeroelastic behaviour caused by a non-symmetric upstream flow affecting the first two rotor blade stages in the axial-compressor of a jet engine. The obtained results show that disturbances in the engine inlet strongly influence the level of unsteady forces acting on the rotor blades. With a partially blocked inlet the whole spectrum of low-frequency harmonics is observed. Such harmonics can lead to rotor blade damage. The lowfrequency amplitudes are higher in the first stage rotor blades than in the second stage. In both rotor blades stages flutter appeared as a result of bird strike.

Authors:

• R. Rzadkowski
• V. Gnesin
• M. Drewczyński
• R. Szczepanik

Keywords:

• Flutter
• unsteady forces
• rotor blades.

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