Penetration Survivable Advanced Energetics

The objective of this work is to provide guidance to explosive formulators and facilitate the development of improved penetrator explosives. Because of the complexity of these materials, it is difficult to relate parameters controllable during formulation to desirable properties in the final product. Formulation variations are limited to modifying the individual constituents in a formulation, their ratios, and the processing methods used, such as mixing and casting techniques. Most commonly, varying a single formulation parameter results in the variation of multiple mesoscale characteristics. It is well established that the mesoscale characteristics of energetic materials are responsible for energy localization and generating damage, “hot spots” and/or bulk reaction. The major impediment to understanding the influence of formulation parameters on explosive sensitivity is that formulation parameters are rarely synonymous with mesoscale characteristics. This is an ideal scenario for contributions via numerical simulation, where the mesoscale characteristics can be individually varied. Isolating the effects of a mesoscale characteristic allows its individual effect on sensitivity to be determined, as well as its relative importance to other mesoscale characteristics, allowing the relevant, irrelevant, and competing consequences of a formulation modification to be identified and evaluated. Similarly, the paramount considerations in developing a new formulation may be identified. BENEFIT: Various formulation variations and their mesoscale effects will be investigated and ranked in order of their importance in penetrator explosive sensitivity. The modeling of energetic constituents and their interactions will be improved and validated. Numerical experiments will be designed to elucidate statistically significant mesoscale effects on bulk response, hot spot distributions, and sensitivity. A suite of experimental results will be generated to characterize bulk and mesoscale response of these materials and validate simulations. WMI will use a two-pronged approach to address the needs of customers who desire to utilize mesoscale simulations to guide the formulation of energetic materials. The first approach is to perform proprietary research and development services. Such R&D services are especially attractive to customers with no current in-house simulation capabilities, yet wishing to fully benefit from the utility and power of mesoscale modeling. The second approach is to release for sale parameterizations of the material and interfacial models developed. This effort targets customers with simulation experience and tools, but who are in need of more sophisticated modeling approaches.