The Development of a Three-Dimensional Material Point Method Computer Simulation Algorithm for Bullet Impact Studies

The study of bullet impacts on various systems is a currently active research field whose results have important meaning for the health and safety of people. Due especially to the destructive nature of bullet insult, computer simulations prove to be very useful in understanding and predicting the behavior of systems involved in such impacts. It is of particular importance to study systems whose components are elastic and can fail. This involves the bullet and target being composed of either a finite element grid or actual particles. In order to study material deformation and failure, we chose the latter scenario. One significant challenge in simulating impact with systems composed of particles is that internal forces need to be communicated throughout the object when it deforms. In order to achieve such communication it is normally thought that a collision algorithm between the particles constituting the system is required which, in three dimensions is quite time consuming. There exists, however a two-dimensional (2D) Material Point Method (MPM) algorithm evaluated by Chan and Brannon [1] which allows modeling of elastic behavior and failure with no contact algorithm, as discussed later. The purpose of this work is to develop a three-dimensional (3D) MPM algorithm and to demonstrate its utility for impact simulations.