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This work deals with numerical simulations of impact problems on fiber-based composite armor using the commercial finite-element-code ANSYS AUTODYN. Having presented some basic knowledge on the theory of numerical simulation in AUTODYN, two recently published approaches for modeling impact on the selected composite (Dyneema® HB26) are explained. Although both of them make use of a nonlinear-orthotropic material model implemented in the AUTODYN-code, they differ in the way how the highly inhomogeneous microstructure of HB26 is represented geometrically. Lässig chooses a fully homogeneous description, whereas Nguyen discretizes the composite into sublaminates, which are kinematically joined at the surfaces and breakable when a certain contact-stress is reached. In order to validate the two approaches, the response of HB26-samples impacted by handgun-projectiles was determined experimentally and compared to the corresponding numerical results. Unfortunately, a poor agreement between experimental and numerical results was found, which gave rise to the development of an alternative modeling approach. In doing so, the composite was subdivided into alternating layers of two different types. While the first type of layers was modeled with open-literature properties of UHMWPE-fibers, polymer-matrix-behavior was assigned to the second type. Having adjusted some of the parameters, good agreement between experiment and simulation was found with respect to residual velocity and depth of penetration for the considered impact situations.

The threat imposed by terrorist attacks is a major hazard for military installations, for example, in Iraq and Afghanistan. The large amounts of rockets, artillery projectiles, and mortar grenades (RAM) that are available pose serious threats to military forces. An important task for international research and development is to protect military installations and implement an accurate early warning system against RAM threats on conventional computer systems in out-of-area field camps. This work presents a method for determining the trajectory, caliber, and type of a projectile based on the estimation of the ballistic coefficient. A simulation-based optimization process is presented that enables iterative adjustment of predicted trajectories in real time. Analytical and numerical methods are used to reduce computing time for out-of-area missions and low-end computer systems. A GUI is programmed to present the results. It allows for comparison between predicted and actual trajectories. Finally, different aspects and restrictions for measuring the quality of the results are discussed.