This thesis presents a sensitivity analysis of the numerical simulation of projectile impact on a thin plate in Abaqus, using the Johnson–Cook plasticity and damage model. Modelling decisions such as symmetry simplifications, mesh density, element dimensionality, and the values of empirical material parameters have a large influence on simulation results. Their effects were evaluated using separate numerical simulations. Results show that the effect of symmetry simplifications on the projectile's velocity history is small, although an asymmetric damage pattern appears in the full, non-simplified model. Mesh density strongly affects both the velocity history and the perforation mechanism; convergence of the residual projectile velocity was not achieved even with the finest mesh used. The shell and solid elements yield similar residual velocities at low and high impact velocities, but differ markedly in the perforation limit and, when perforation occurs, in the perforation mechanism. A full factorial design of experiments on the plasticity parameters showed a strong influence of parameter B, a moderate influence of C, and a negligible influence of n, with no reliable interaction effects detected. As the results were not experimentally validated, the thesis does not provide reliable absolute predictions, but evaluates relative changes due to modelling decisions.
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