Aircraft turbine fan casing and ballistic fan blade impact: Geometry and material

If the failed fan blade (FB) is not contained in the fan casing (FC) at the time of failure, a catastrophic disaster could follow from the failure of the aircraft's engine turbine. Unfavorable problems including the aircraft malfunctioning, a potential engine shutdown, and even a crash could occur if the detached FB enters the FC. This study employed the Finite Elements Method (FEM) to examine the effects of utilizing Polyether Ether Ketone (PEEK) as an alternative FB material on the FC in order to address this issue. In order to investigate the effects of PEEK and aluminum ballistic FB penetration on FC with thicknesses of 5, 4, 3, and 2 mm at 255 m/s, a FEM ballistic model was developed using the ABAQUS/Explicit modeling system. It was found that during working conditions, none of these FBs could pierce the FC, regardless of thickness. PEEK might be a better alternative, though, as the FC was more obviously deformed by the metal FB. The decision was made to conduct additional analytical validation of the developed FE models. The moment of inertia methodology, a novel approach, was employed. There was a strong correlation between the results of the FE models and the analytical answers. Therefore, it may be said that PEEK is a better material than aluminum for making blade casings.