Composition B is a melt-castable explosive consisting of RDX crystals in a TNT matrix. At elevated temperatures, the TNT can flow or even melt, which affects the particle distribution and therefore the detonation propagation. To study this phenomenon, rate stick experiments were conducted at ambient conditions, at temperatures below the TNT melt, and at temperatures above the TNT melt. We field...

The results of experimental studies during which transition to detonation events occurred are presented. These observations and their interpretation are then discussed, and the conditions for the onset of detonation are described, with particular attention paid to the nature of the phenomena of deflagration-to-detonation transition. The resulting implications for predicting detonation evolution...

An experimental study on pulse detonation engine (PDE) is conducted using hydrogen/air mixtures. Several key issues for PDE development, including valve operation, injection, mixing, filling, cycle repetition, ignition timing, DDT distance and propagation of detonation/quasi-detonation, are investigated. The fuel and oxidizer are injected into PDE from opposite sidewall directions to be well mi...

The research was conducted to study the thermal conductivity of detonation nanodiamonds-based composites. Composite nanodiamond materials were obtained in course thermobaric sintering at press-free high-pressure apparatus (BARS) under 5 GPa and temperatures within range 1100 –1500°С. It ascertained that unlike diamond monocrystals with their reaching up 2100 W / (mK), a composite is considerabl...

The WBL model for detonation wave propagation was extended to allow more general initiation in the context of level set methods. Initiation could then be induced fairly seamlessly from reactive flow simulations. The accuracy of WBL detonation compared favourably with results from full reactive flow, and proved surprisingly robust with respect to changes in numerical parameters used to trigger W...

Aims. We present the first full-star three-dimensional explosion simulations of thermonuclear supernovae including parameterized deflagration-to-detonation transitions that occur once the flame enters the distributed burning regime. Methods. Treating the propagation of both the deflagration and the detonation waves in a common front-tracking approach, the detonation is prevented from crossing a...

Two structurally interesting 3,6-dinitropyrazolo[4,3-c]pyrazole-based energetic cocrystals were prepared and confirmed by single crystal X-ray diffraction. As novel energetic materials, these two unusual neutral acid-base complexes possess high nitrogen content, good detonation properties, and improved impact and friction sensitivities which highlight their potential energetic applications.

The Deflagration to Detonation Transition (DDT) in large arrays (100s) of explosive devices is investigated using large-scale computer simulations running the Uintah Computational Framework. Our particular interest is understanding the fundamental physical mechanisms by which convective deflagration of cylindrical PBX 9501 devices can transition to a fully-developed detonation in transportation...