Document Type : Research Paper



Foreign object damage (FOD) occurs when hard, millimeter-sized objects such as gravel or sand and even the pieces of the engine components are ingested into aircraft jet engines. Particles impacting blades produce small indentation craters which can become sites for fatigue crack initiation, severely limiting the lifetime of the blade. In this study, the impact on the edge of a thin plate is investigated by using the finite element method. Then residual stresses are compared between the quasi-static indentation and fully dynamic impact for three critical locations where the residual hoop stresses are tensile. At the end, experimental stress analysis is performed for investigating the stress concentration factor at the crater base and comparing with data from the finite element method. The comparison shows that the finite element method result agrees well with experimental data at the crater base.