Grain-scale Dynamics in Explosives

Reaugh, J E

Lawrence Livermore National Laboratory

关键词: Mechanical Properties;    Chemical Properties;    Stimuli;    Binders;    Chemical Explosives;   

DOI  :  10.2172/15003150
RP-ID  :  UCRL-ID-150388
RP-ID  :  W-7405-ENG-48
RP-ID  :  15003150

美国|英语

来源: UNT Digital Library

【 摘 要 】

High explosives can have reactions to external stimuli that range from mild pressure bursts to full detonation. The ability to predict these responses is important for understanding the performance as well as the safety and reliability of these important materials. At present, we have only relatively simple phenomenological computational models for the behavior of high explosives under these conditions. These models are limited by the assumption that the explosive can be treated as homogeneous. In reality the explosive is a highly heterogeneous composite of irregular crystallites and plastic binder. The heterogeneous nature of explosives is responsible for many of their unique mechanical and chemical properties. We use computational models to simulate the response of explosives to external mechanical stimuli at the grain-scale level. The ultimate goal of this work is to understand the detailed processes involved with the material response, so that we can develop realistic material models, which can be used in a hydrodynamics/multi-physics code to model real systems. The new material models will provide a more realistic description of the explosive system during the most critical period of ignition and initiation. The focus of this work is to use the results of grain-scale simulations to develop an advanced macroscopic reactive flow model that is consistent with our understanding of the grain-scale details, and that can incorporate such information quantitatively. The objective is to connect changes to observed properties of the explosive (grain size distribution, binder thickness distribution, void shape, size, and separation distribution, binder mechanical properties, etc.) with predictions of the resulting sensitivity and performance.