Characterizing the shock sensitivity of Hexanitrostilbene by flyer impact experiments and simulations

The shock sensitivity and ignition behavior of explosives and propellants are important safety characteristics for developing insensitive munitions (IM) and ignition systems. Material properties related to shock sensitivity are usually examined in initiation experiments such as flyer impact or gap tests resulting in critical velocities or gap lengths. With advanced methods, models for describing and simulating the initiation behavior of explosives are derived from these experiments but the universality of these models, e.g. I&G and HVRB, is questionable. Generally, these must be tuned for each experiment and depend on the experimental results, from which they are generated. Pop-plots from extensive experiments are usually the basis for optimizing these ignition models used in hydro codes. In this work different initiation models are evaluated for the applicability to predict the results of flyer impact experiments, using different hydro codes. Therefore, initiation models and parameters for HNS available in literature are used in flyer impact simulations and the results are compared and assessed based on the critical flyer velocity with respect to initiation. For deriving future initiation models an experimental setup for the generation of Pop-plots is introduced which could reduce the experimental effort in the future. This setup utilizes the miniaturized velocity of detonation measurement method, formally developed at Fraunhofer ICT.