Influence of the shock pulse duration Definition on the Location of the Initiation Threshold in the James Criterion

The definition of the shock pulse duration τ is crucial for initiation criterions like those of Walker and Wasley or James. The determination is performed experimentally and empirical definitions for common projectile geometries exist. Bouma et al. proposed a definition of τ independent of the shock wave profile. However, these definitions are used for flyer and projectile impact experiments in optimal one-dimensional conditions. We investigated the influence of the shock pulse duration definition on the location of the initiation threshold in the James criterion by simulating different gap tests in SPEED and comparing the results to flyer impact simulations with HNS using experimental literature data.