Combustion chambers of aircraft engines are exposed to oxidation, corrosion, and high thermo-mechanical loads. Accordingly, they are particularly vulnerable to damage and defects. Such defects of combustion chambers can introduce a non-uniform flow and a distortion at the downstream turbine inlet. This distortion at turbine inlet can lead to forced response excitation of the downstream turbine blades. In this study, forced response excitation due to three different inlet temperature profiles is numerically investigated using a fluid-structure interaction (FSI) approach previously validated in a five-stage axial air turbine. The focus of this study is the aerodynamic excitation due to the combustion chamber defects and the influence on the excitation of the downstream turbine blade row. The results show that the distortion at turbine inlet creating by the combustion chamber can lead to a significant increase of the excitation of the downstream blades. The present distortion due to the combustion chamber with defects leads to a threefold higher vibration amplitude compared to normal operating conditions. These high amplitudes cause high dynamic stress levels in the blades and reduce the life cycle of the blades.
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