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Introduction
Uncontained engine rotor failure (UERF) is any failure that results in rotor fragments escaping from the aircraft engine and leads to hazards to the structure and systems of the aircraft. Engines in operation are always working in harsh conditions of high load, high temperature and high revolving speed; therefore, ill-structure design, material defects, mechanical fatigue or other factors may result in the rotor failure. Although turbine engine manufacturers are making efforts to optimize design and machining technology to reduce the probability of uncontained rotor failures, service experience shows that uncontained compressor and turbine rotor failures still occur (Rao, 2011). UERF has resulted in high-velocity fragment penetration of adjacent structures, fuel tanks, fuselage panels, system components and even other engines. It is a typical particular risk that imposes threat on the flight safety.
Many scholars have performed theoretical and experimental studies and developed analytical models of the rotor burst and uncontained rotor failure process. Dewhurst and Tang (1995) used experimental data from a multiple blade shed incident to determine impact forces exerted by the blades. Sarkar and Atluri (1996) used a finite element analysis to study the impact of rotor blade fragments that are produced during an aircraft jet engine rotor failure and determined residual kinetic energy level of the fragments, magnitude of impact forces and the overall containment or failure. Lesuer (2000) presented the deformation and failure response of Ti-6AMV and 2024-T3 under conditions relevant to simulations of engine containment and the influence of uncontained engine debris on aircraft structures. Pereira et al. (2001) studied the effects of heat treatment on the ballistic impact properties of Inconel 718 for jet engine fan containment applications. MacDonald (2002) presented a computational and experimental analysis of high-energy impact of rotor fragments to sheet metal aircraft structures. Jaunky et al. (2000) proposed modeling and simulation requirements for uncontained engine debris impact on fuselage skins, assessed using the tied-nodes-with-failure modeling approach for penetration and simulated the effect of uncontained engine debris impacts on aircraft fuselage-like skin panels. Varas et al. (2012) simulated a hydrodynamic ram event created by a steel spherical projectile impacting a partially water-filled aluminium square tube to support the design of wing fuel tanks of aircraft. FAA AC 20-128A (1997) set forth design considerations for...