Composite materials and bird-strike analysis using explicit finite element commercial codes

摘要

The impact of a bird represents one of the most dangerous events for the safety of the modern aircraft. Statistics report that the consequences can be tragic, especially for the small airplanes. In this work, the impact of a bird against a nacelle inlet is analysed by the means of a proven Explicit Finite Element (FE) code, LSTC LS-Dyna. In particular, the dynamic characterisation of the composite materials used in manufacturing the external skin of the inlet was achieved by referring to the drop-tests carried out using thin walled tubes of the same material. The data collected were used to define and tune the damage law of the numerical model. Once the material constitutive model was validated, an actual bird impact test was numerically analysed. In particular, two different bird models were considered: the customary Finite Element and the nodal masses bird model. The numerical results obtained were eventually qualitatively compared with experimental. In conclusion, some remarks on the results obtained are made.