Status of FE simulation methods for certification of composite structures under high velocity impact

The paper discusses FE simulation methods in use for predicting impact damage in advanced composite structures. Before these simulation tools are accepted by the industry for design and certification of composite aircraft structures, composites damage models have to be developed, implemented in commercial FE codes and validation studies at specimen and substructure level have to be performed. For vulnerability analysis the DLR uses meso-scale composites ply damage models with an energy based delamination failure criteria in explicit FE codes to study damage progression in composite structures under impact. The methods developed are summarised in the paper and applied to predict impact damage in stiffened aircraft panels from hard debris impact and tyre rubber fragments. Issues concerned with use of such computational methods for certification by analysis are discussed