The Study of Hydrodynamic Jets in Triangular Shaped Voids in Detonating Primasheet 1000.

Macroscopic features in high explosive materials such as gaps, interfaces, and voids significantly influence detonation behavior and performance. Although extensive research has examined the interaction between detonation waves and millimeter-scale voids, centimeter-scale voids—amenable to current machining and additive manufacturing techniques—remain underexplored despite their potential for novel detonation dynamics. Prior studies have shown that different machined void geometries can trigger unique phenomena: rectangular channels generate high speed jets that outpace the unperturbed detonation wave, cylindrical voids introduce propagation delays, and semi-cylindrical voids focus detonation products to enhance and localize energy output. Triangular voids uniquely combine these effects in a manner that is dependent on their aspect ratio. Building on previous numerical simulations and experimental investigations, this study examines how the aspect ratio of centimeter-scale triangular voids influences detonation wave propagation in energetic materials. Experiments conducted with Primasheet 1000 (a PETN-based rubberized explosive) revealed that increasing the void aspect ratio from 4 to 9 leads to a significant enhancement in hydrodynamic jetting of detonation product gases. Furthermore, three-dimensional effects and the absolute void size were found to critically affect jet formation. These insights offer a promising pathway for optimizing the design and performance of energetic materials.