Shock and shear initiation of explosive

Three reaction-rate models, Forest Fire, Arrhenius and a combined Forest Fire and Arrhenius, are incorporated in the hydrocode DEFEL. Simulations with this code for PBX-9404 explosive for bare and covered explosives by fragment impact are made. Results confirm the well-known shock-initiation theory for bare explosives. For explosives with a thick cover plate, code results show macroscopic shear initiation, as proposed by Howe (1985) and Frey (1981).This article was processed using Springer-Verlag TEX Shock Waves macro package 1990.