Transverse Initiation and Wavefront Breakout at High Explosive Interfaces.

Interactions between high explosives (HE) of differing detonation behaviors is complex. Simulations and experiments are presented that explore the transverse shock initiation in rate sticks of two adjacent slabs of explosives of different explosives. Each HE layer is either a higher performance, HMX-based explosive, a lower performance, TATB-based explosive, or a blend of the two. In this configuration, the slab with the faster detonation velocity transversely initiates the slower high explosive side thus driving the phase velocity of the entire rate stick, producing a wavefront breakout shape that captures details of the transverse initiation in the slower detonation velocity side. From the measured experimental detonation velocities measured and wavefront breakout profiles captured with streak imaging, optimized rate parameters for the reactive flow model [RRV1] were calculated. The performance of the optimized model is reported over the entire set of rate stick composition pairs.