Detonation velocity/diameter relation in gelled explosive with inert inclusions

The detonation velocity is measured in a gelled explosive that has been sensitize via the addition of glass microballoons (GMBs) and additionally diluted via large-scale inert inclusions. The explosive is nitromethane that has been gelled via the addition of poly(methyl methacrylate) (PMMA) and then sensitized via hot-spot inducing glass microballoons (GMBs, 3M K-1). Inert inclusions consisting of pellets of polyether block amide (PEBA, 2–3 mm in size) are then added to the explosive to make a heterogeneous explosive with heterogeneities that are at a scale disparate from those of the microballoons. The PEBA is density matched to the NM/PMMA/GMB mixture such that the large pellets remain in suspension. This system has the potential to be a synthetic explosive that can be tuned to have the properties of morphologically complex commercial blasting explosives. The velocity-diameter and velocity-thickness relation is measured using weakly confined (polyvinyl chloride) cylindrical and slab charges, respectively. The results are also used to further explore the phenomenon of anomalous scaling between axisymmetric and two-dimensional geometries.