Simulating the Formation and Evolution of Behind Armor Debris Fields

The performance of the CTH shock physics code was evaluated on the Opteron cluster recently installed at the U.S. Army Research Laboratory Major Shared Resource Center. Scalability trials were conducted using up to 2048 processors and involved the simulation of the yawed, oblique impact of a long rod penetrator with a thin plate. The scalability of CTH on the Opteron cluster was studied for both fixed and adaptive meshes. After the scalability study was completed, CTH simulations were conducted to evaluate the potential to use shock physics simulations to augment experimental data in behind armor debris applications. These simulations were conducted for both fixed and adaptive meshes. A variation of a fracture model currently under development at ARL also was evaluated. Behind armor debris is a major cause of damage in military vehicles that have been perforated by a penetrator, bullet or fragment. The ability to predict the debris field resulting from attack by such a threat is critical to assessing and improving the survivability of tactical systems. The ARL Weapons and Materials Research Directorate has been working to develop the capability to model numerically the behind armor debris resulting from armor perforation. Past modeling of the debris field has been done by statistically analyzing data from carefully controlled experiments. The difficulty of collecting this information makes it an expensive and lengthy process. Supplementing these experiments with numerical simulations has not yet been successfully exploited because previous computers were unable to cope with the daunting size of the simulations. With the addition of the Opteron cluster to the ARL MSRC, numerical modeling of these experiments is now within reach. The experiment modeled consists of a 30-mm Armor Piercing Discarding Sabot round perforating a 1-inch-thick armor steel plate. The resulting behind armor debris impacts a large, thin, mild steel witness plate placed 610 mm behind the armor. Presented at the 2005 DoD High Performance Computing Users Group Conference held in Nashville, TN, on 27-30 Jun 2005. Project No. 622618AH80. The original document contains color images.