A Computational Study of Denotation Failure in Composition B and Cast TNT Charges

In order to obtain a broader understanding of the utility of the Forest Fire explosive initiation model in predicting detonation failure, we made computations using the 2DE code to predict failure diameter and thickness for Composition B and cast TNT. The computations reveal oscillatory detonations near the failure dimension. The computed failure radius is nearly equal to the corresponding failure thickness. The predictions are accurate for Composition B and reasonably close for cast TNT. We also made 2DE computations of detonation failure in singly perforated grains of each explosive using Forest Fire. For these grains, detonation fails when the failure thickness exceeds the difference between the grain and perf radii. Consideration of the expected behavior when failure radius and thickness are not equal leads to the conclusion that sensitivity of perfed grains is lowest in materials for which failure radius exceeds failure thickness. Explosives, Detonation, Critical diameter.