Initiation of Annular Insensitive High Explosives Using a Center Axial Conventional High Explosive Charge

Geometry plays a key role in explosives performance due to how the shock and energy propagate through the sample. Next to failure diameter, the most critical performance metric for geometry effects is corner turning. All explosives can exhibit dead-zones (regions where the explosive does not detonate promptly) when charge geometry forces detonation corner turning, but for Conventional High Explosives (CHEs) the effected area is small and typically negligible. However, Insensitive High Explosives (IHEs) struggle to corner turn resulting in large dead-zones that do not assist in the propagation of the detonation, and significantly reduce or delay the energy release from the charge. To explore this process an experiment has been designed with a center charge of CHE that is partially inserted into a hollow annular charge of IHE. Mirror destruct and flash coating streak imaging will be fielded to measure corner turning breakout along the annular charge and output surface. Photonic Doppler Velocimetry (PDV) will also be fielded to measure shock pressure at discrete locations. The development of the shock front along the annular charge will be investigated through a series of cut back experiments. These data will provide insight on initiation in axisymmetric charges and the development of the detonation front within annular geometries.