AbstractBird strikes are issues as old as aviation dating back in 1912 and is still apparent in day-to-day aircraft incidents that costs revenue to the aerospace industries. Aircraft wing is one of the most critical components of aero structures, which provides support to the entire aircraft. In this study, a crash and impact analysis of a high velocity business aircraft composite wing leading edge has been performed with a numerical bird model using advanced simulation software LS-DYNA. The failure criteria are assessed using maximum stress theory and Chang-Chang failure criteria.
The numerical hemispherical-ended cylinder shape bird was modelled using Smooth Particle Hydrodynamics (SPH) method which is a meshless approach and gives the possibility of dealing with larger distortion compared to grid-based methods. The ribless leading edge of the wing was modelled inCATIAV5and meshed with shell elements in Hyper Mesh. Glass Laminate Aluminium Reinforced Epoxy (GLARE),which is composed of several very thin layers of aluminium interspersed with layers of glass-fibre was used for the deformation analyses after impact. The layup of the GLARE was similar to the C-27J aircraft wing leading edge outboard layup and in the order of A/0/90/A/90/0/A where A is for Aluminium alloy 2024-T3 and 0/90/90/0arethe fiber orientations of the Glass-Fibre Reinforced Plastic (GFRP) also known as fiberglass. Johnson-Cook (MAT_015) material card was used for AL2024-T3 whereas Composite Damage (MAT_022) material card was used for GFRP to assess three failure modes -longitudinal tensile failure mode along the fiber, transverse tensile and compressive failure mode along the matrix. Two test cases were considered for the impact assessment –the first test case reflected the landing and take-off scenario in which the bird impact at 116 m/s, whereas the impact velocity of the bird was increased to 129 m/s in the second test case. The second test case results were compared with the theoretical and numerical result obtained from the C-27 J aircraft certification. In both the test cases, all the fiberglass piles failed and the aluminium alloy plies plastically deformed but without the bird SPH particles penetration through the leading edge. The leading edge was able to absorb the impact energy but with permanent deformation.
|Date of Award||2016|
|Supervisor||Jesper Christensen (Supervisor)|