FE analysis of geometry effects of an artificial bird striking an aeroengine fan blade

• Published in: International journal of impact engineering Vol. 35; no. 6; pp. 487 - 498
• Main Authors: Meguid, S.A., Mao, R.H., Ng, T.Y.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.06.2008; Elsevier Science
• Subjects: Artificial bird configuration; Aspect ratio; Bird strike; Exact sciences and technology; Flexible fan blade; Fracture mechanics (crack, fatigue, damage...); Fundamental areas of phenomenology (including applications); Mechanical contact (friction...); Physics; Rigid panel; Solid mechanics; Structural and continuum mechanics; Vibration, mechanical wave, dynamic stability (aeroelasticity, vibration control...); Bird strike; Rigid panel; Flexible fan blade; Aspect ratio; Artificial bird configuration; Rigid bodies; Transient response; Vibration; Turbojet; Mechanical contact; Experimental study; Modeling; Certification; Contact surface; Finite element method; Vertebrata; Size effect; Turbine blade; Gas turbine; Aves; Non linear effect; Aircraft; Ellipsoid
• ISSN: 0734-743X; 1879-3509
• DOI: 10.1016/j.ijimpeng.2007.04.008

Bird strike resistance of aeroengines is a strict certification requirement. Apart from costly experimental bird strike tests, explicit numerical modeling techniques have been employed. However, due to the complicated bird geometry, artificial bird models are still not well defined and it is a perennial problem selecting an appropriate representative artificial bird geometry for the simulations. To examine the relative effects of the artificial bird geometry, explicit 3-D finite element analyses are conducted herein using the commercial code LS-DYNA. As a validation test, we first studied the nonlinear transient dynamic response of an artificial bird striking a rigid flat target. Following the validation, we studied the impact behavior of an artificial bird impinging a flexible aeroengine fan blade. The study focused on the three most-frequently used configurations in the literature: namely, hemispherical-ended cylinder, straight-ended cylinder, and ellipsoid, at various length-to-diameter aspect ratios. The results show that the initial contact area between the bird and target in the early phase of the impact event would have a significant effect on the peak impact force. The aspect ratio of the bird striking both rigid panel and flexible fan blade was found to have little influence on the normalized impact force and impulse.