Validation of near-field blast loading in LS-DYNA

The detonation of a high explosive releases a significant amount of energy over a very small timescale, resulting in the propagation of shock waves with MPa-GPa magnitudes and µs-ms durations. Whilst current numerical modelling approaches can simulate high explosive blast events through the solution of conservation laws, the scarcity of definitive, repeatable, and high-quality experimental data has prohibited any detailed validation studies from being conducted. As such, the accuracy of numerical approaches remains largely unquantified. This paper presents the results from a series of experimental trials where the reflected blast pressures from spherical and cylindrical high explosives were directly measured. These results are used to validate LS-DYNA numerical simulations. It is shown that spherical charge simulations are in excellent agreement with the experiments, however the agreement between model and experiment was poor for the cylindrical charge simulations. Despite this, the fireball expansion rate is shown to be similar between model and experiment, suggesting that qualitative validation data should be used with caution for near-field blast events.