Comparison of multidimensional calculations of long-rod impacts on oblique plates

The justification for three-dimensional versus two-dimensional simulations of non-symmetric armor penetration problems has been a topic of discussion for many years. Two-dimensional plane-strain approximations are generally not quantitatively accurate, especially at later times, but they can be performed efficiently and the results are usually acceptable. Although three-dimensional calculations provide better results, they are very time consuming and expensive to perform. But with the improved speed and memory capabilities of modern computers, it is now more feasible to perform three-dimensional calculations. In this study, we compare two- and three-dimensional Eulerian calculations performed with the HULL hydrodynamic computer code with experimental data from oblique impacts of uranium-alloy penetrators into rolled homogeneous armor targets. The results of this study indicate that the three- dimensional calculations provide the best predictions of experimental data and are reasonably efficient to perform considering the improved accuracy of the calculation over comparable two-dimensional calculations. 2 refs., 8 figs., 2 tabs