Computational simulations of the dynamic compaction of porous media

The goal of this study was to apply and compare different computational compaction models to the dynamic compaction of porous silicon dioxide (SiO2) powder. Three initial specific volumes were investigated in this study, V00=1.3, 4 and 10 cm3/g, where the solid material specific volume is V0=0.4545 cm3/g. Two hydrodynamic codes, KO and CTH, were used to simulate the experimental results. Two compaction models, P–α and P–λ were implemented within CTH in conjunction with the Mie–Grüneisen (MG) equation of state. The snowplow (SP) compaction model was implemented within KO. In addition, the MG equation of state based on the experimentally measured Hugoniot was implemented within CTH and was compared to the data as well. One-dimensional flyer plate experiments were conducted with impact velocities ranging from 0.25 to 1.0 km/s, which corresponded to a shock incident pressure range of 0.77–2.25 GPa. The computational simulations were compared to the temporal lateral stress signatures measured with manganin gauges, placed before and after the silica powder. It was found that the MG equation of state (EOS) most accurately reproduce all of the experimental data whereas none of the compaction models accurately reproduced all of the experimental data. However, of the compaction models investigated that the P–α model tended to outperform the other considered.