Vibration Analysis of Notched Damaged Aero-engine Compressor Blades

Compressor blades are important components in aero-engines and are prone to foreign object damage (FOD). FOD-damaged compressor blades are susceptible to fracture under vibration loads, severely risking the aircraft safety. Hence, this paper aims to investigate vibration characteristics of FOD-damaged compressor blades through experimental and finite element (FE) analysis. To accomplish this, vibration test is conducted by applying a 3D full-field scanning laser vibrometry method and the experimental results are compared with numerical results. A good consistency is observed between the experimental results and numerical predictions. Moreover, damaged compressor blade models with FOD of different depths are established based on the validated model, and are successfully utilized for studying the static and dynamic modal analysis of damaged blades. The results demonstrate that the increase in the depth of notch damage leads to the reduction of natural frequency of blade, threatening the safety of aero-engines.