Abstract Continuum equations are numerically integrated
using a high-resolution method to characterize the thermomechanical
response due to planar impact of initially stressfree
granular solid having spatially varying bulk porosity.
This response depends on strain history because the crushup
stress necessary for inelastic compaction increases with
initial solid volume fraction (φ0). Emphasis is placed on characterizing
the influence of initial porosity and piston speed
on both the grain surface heat flux variation and peak temperature
rise within compaction wave profiles for the granular
explosive HMX(C4H8N8O8). Heat fluxes near 586MW/m2,
resulting in temperature rises in excess of 400 K, are predicted
for weak compaction of granular HMX having an initially
dense region adjacent to a highly porous region (φ0 =
0.99, 0.655). Phenomena associated with reflected and transmitted
waves from material interfaces are highlighted. Predicted
compaction zone end states and heat flux profiles are
shown to agree well with those given by a steady-state theory