Zhao Zhenhua

Foreign Object Damage to Fan Rotor Blades of Aeroengine Part II: Numerical Simulation of Bird Impact

Abstract Bird impact is one of the most dangerous threats to flight safety. The consequences of bird impact can be severe and, therefore, the aircraft components have to be certified for a proven level of bird impact resistance before being put into service. The fan rotor blades of aeroengine are the components being easily impacted by birds. It is necessary to ensure that the fan rotor blades should have adequate resistance against the bird impact, to reduce the flying accidents caused by bird impacts. Using the contacting-impacting algorithm, the numerical simulation is carried out to simulate bird impact. A three-blade computational model is set up for the fan rotor blade having shrouds. The transient response curves of the points corresponding to measured points in experiments, displacements and equivalent stresses on the blades are obtained during the simulation. From the comparison of the transient response curves obtained from numerical simulation with that obtained from experiments, it can be found that the variations in measured points and the corresponding points of simulation are basically the same. The deforming process, the maximum displacements and the maximum equivalent stresses on blades are analyzed. The numerical simulation verifies and complements the experiment results.

Foreign Object Damage to Fan Rotor Blades of Aeroengine Part I: Experimental Study of Bird Impact

Abstract The conditions of experiment for bird impact to blades have been improved. The experiment of bird impact to the fan rotor blades of an aeroengine is carried out. Through analyzing the transient state response of blades impacted by bird and the change of blade profile before and after the impact, the anti-bird impact performance of blades in the first fan rotor is verified. The basis of anti-foreign object damage design for the fan rotor blades of an aeroengine is provided.

Numerical simulation methodology of multi-layer Kevlar 49 woven fabrics in aircraft engine containment application

ABSTRACT A numerical simulation method was developed to provide effective tools to estimate the ballistic resistance of Kevlar 49 fabric for gas turbine engine containment system in LS-DYNA. Material model based on representative unit cell and three-element viscoelastic constitutive equation was employed to describe the dynamic response of single-layer and multi-layer fabrics. The influences of mesh size, hourglass control method in the material model were discussed. The numerical simulation method is used to predict the ballistic performance of Kevlar fabrics in testing condition. The failure mechanism, the stress wave propagation and energy absorption mechanism were investigated and compared with testing results and achieved good agreements. It is indicated that the developed numerical method provides promising results in modelling the high-speed ballistic impact events and engine fan blade off events.