[en] The principal task of our studies is to provide a rational interpretation of the thermodynamic and fluid dynamic events taking place in a closed vessel upon detonation of an explosive charge and subsequent turbulent combustion of its products, acting as fuel for an exothermic reaction with air. Under such circumstances, the latter has been compressed by a reverberating shock front of the blast wave generated by the explosion. The paper presents the chemical and thermodynamic background and its numerical results, deduced for this purpose from mass spectroscopic data and pressure records, acquired upon explosion of a 0.8 kg charge of TNT in a 17 m³ chamber filled with air--a diagnostic analysis identified by the title. The evolution of the flow field and its structure are presented in a companion paper

[en] A theoretical model of combustion in explosions at large Reynolds, Peclet and Damkoehler numbers is described. A key feature of the model is that combustion is treated as material transformations in the Le Chatelier state plane, rather than ''heat release''. In the limit considered here, combustion is concentrated on thin exothermic sheets (boundaries between fuel and oxidizer). The products seem to expand along the sheet, thereby inducing vorticity on either side of the sheet that continues to feed the process. The results illustrate the linking between turbulence (vorticity) and exothermicity (dilatation) in the limit of fast chemistry--thereby demonstrating the controlling role that fluid dynamics plays in such problems

[en] The interaction of the detonation of a solid HE-charge with a non-premixed cloud of hydro-carbon fuel in a chamber was studied in laboratory experiments. Soap bubbles filled with a flammable gas were subjected to the blast wave created by the detonation of PETN-charges (0.2 g < mass < 0.5 g). The dynamics of the combustion system were investigated by means of high-speed photography and measurement of the quasi-static chamber pressure

[en] Energetic materials are being considered for the neutralization of spore-forming bacteria. In this study, the neutralization effects of a monomolecular explosive were compared to the effects of halogen-containing thermites. Bacillus atrophaeus spores were exposed to the post-detonation environment of a 100 g charge of the military explosive C-4 at a range of 50 cm. These tests were performed in the thermodynamically closed environment of a 506-l barometric calorimeter. Associated temperatures were calculated using a thermodynamic model informed by calculations with the Cheetah thermochemical code. Temperatures in the range of 2300–2800 K were calculated to persist for nearly the full 4 ms pressure observation time. After the detonation event, spores were characterized using optical microscopy and the number of viable spores was assessed. Results showed live spore survival rates in the range of 0.01%–1%. For the thermite tests, a similar, smaller-scale configuration was employed that examined the spore neutralization effects of two thermites: aluminum with iodine pentoxide and aluminum with potassium chlorate. Only the former mixture resulted in spore neutralization. These results indicate that the detonation environment produced by an explosive with no chemical biocides may provide effective spore neutralization similar to a deflagrating thermite containing iodine