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Aeroelasticity analysis of a bird-damaged fan assembly using a large numerical model

Published online by Cambridge University Press:  04 July 2016

M. Imregun
Affiliation:
Mechanical Engineering Department, Imperial College of Science, Technology and Medicine, London, UK
M. Vahdati
Affiliation:
Mechanical Engineering Department, Imperial College of Science, Technology and Medicine, London, UK

Abstract

Bird strike is a major consideration when designing fans for civil aero engines. Current methods rely on impact tests and structural optimisation but it is highly desirable to have predictive numerical models to assess the aerodynamic and aeroelastic stability of bird-damaged fan assemblies. A detailed feasibility study towards such a prediction capability, consisting of a CFD solver coupled to a finite element representation of the structure, is reported in this paper. A whole-assembly model was used for both the fluid and the structural domains, an approach necessitated by the loss of cyclic symmetry due to one or more blades undergoing plastic deformation under the effect of the bird impact. It was assumed that two consecutive blades had suffered unequal amount of bird damage, the so-called heavy and medium-damaged blades.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 1999 

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