27th International Symposium on Ballistics 2013, April 22-26 2013, Freiburg, Germany
Fragments of aluminium impacting on Composition B explosives encased in rolled homogenous armour (RHA) steel were investigated using the explicit nonlinear finite element method. The investigation focused on shock to detonation simulations of Composition B, with the objective of determining the critical velocity which would generate a shock wave strong enough to cause detonation of the explosive and the resulting pressure profile of the detonation wave. Detonation scenarios at low, intermediate, high impact velocity were investigated. It was observed that a) at intermediate velocities detonation was due to the development of localized hot spots caused by the compression of the explosive from the initial shockwave; b) at high impact velocity, initiation of the explosive was caused by the initial incident wave behind the top casing/explosive interface. c) At low impact velocity, initiation of the explosive may be caused by the increased pressure of reflecting waves against the surfaces of the explosive casing. This case served to show the importance of capturing all confining surfaces correctly as any surface enhance detonation. Advanced features of the simulation includes Arbitrary-Lagrangian-Eulerian (ALE) approach, the Elastic Plastic Hydrodynamic constitutive material model and the Ignition and Growth of Reaction in High Explosive eq uation of state (IGRHE-EOS) to account for the probability that the explosive may not detonate when impacted.
DEStech Publications Inc.
Proceedings - 27th International Symposium on Ballistics, BALLISTICS 20131: 916–927.