Regardless to the efforts provided and the progresses achieved, birdstrike still represents a serious menace for flight safety. A birdstrike is characterised by large nonlinear elastic and inelastic deformations, high strain rate and high impact loads transferred in a very short time. The mutual dependency of impact loads and structure response calls for the use of advanced numerical techniques. In particular, nonlinear explicit finite element codes have shown to be a reliable tool to design bird-proof structures. In finite element analyses, the bird model is central. In view of that, various approaches to model the bird are considered referring to normal and oblique impacts onto a rigid target. Differently from other similar works focused only on flesh-and-bones birds, here, also artificial (jelly) birds are considered. The customary Lagrangian, Eulerian and Arbitrary Lagrangian Eulerian approaches are compared with the Smoothed Particle Hydrodynamics, the Discrete Element and the Element Free Galerkin ones. Eventually, findings and guidelines for using of these models are obtained.
Birdstrike: an Investigation on Feasible Bird Models for Nonlinear Explicit Finite Element Analyses
ANGHILERI, MARCO;CASTELLETTI, LUIGI MARIA LEONARDO;
2006-01-01
Abstract
Regardless to the efforts provided and the progresses achieved, birdstrike still represents a serious menace for flight safety. A birdstrike is characterised by large nonlinear elastic and inelastic deformations, high strain rate and high impact loads transferred in a very short time. The mutual dependency of impact loads and structure response calls for the use of advanced numerical techniques. In particular, nonlinear explicit finite element codes have shown to be a reliable tool to design bird-proof structures. In finite element analyses, the bird model is central. In view of that, various approaches to model the bird are considered referring to normal and oblique impacts onto a rigid target. Differently from other similar works focused only on flesh-and-bones birds, here, also artificial (jelly) birds are considered. The customary Lagrangian, Eulerian and Arbitrary Lagrangian Eulerian approaches are compared with the Smoothed Particle Hydrodynamics, the Discrete Element and the Element Free Galerkin ones. Eventually, findings and guidelines for using of these models are obtained.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.