Various sympathetic reaction tests were conducted on PBXN-109 donors confined in mild steel cases initiating both bare and cased acceptors with different standoff distances. Fragment capture experiments were also performed to better understand the relationship between fragment penetration and acceptor response. Concurrent with the experimental study, the sympathetic detonation initiated by donor case was simulated using the hydrocode LS-DYNA with the two DSTO-developed Ignition and Growth models. Two techniques were investigated for modelling donor case. One method was to use either the Johnson-Cook strain fracture damage model in conjunction with an equation of state or the plastic kinematic model applying the element erosion criteria. Another was to treat the donor case as controlled pre-fragmentation where the fragment size, type and the number distribution were determined using the Mott model considering both the typical fragment recovered from the tests and the donor worst credible mass fragment. Finally, the shock sensitivity curve that summarises the critical combination of peak shock pressure P and the derived parameter P~2 t was developed for PBXN-109 explosive based on the simulated pressure-time history results at the interface between the case and the charge. For a given sensitivity curve, there were two asymptotes which could be used to predict the conditions for initiation of detonation of an explosive subjected to shock.
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