Dependence of Critical Diameter of Emulsion Explosive on Density in Steel Confinement

Abstract

Emulsion explosives (EMX) based on fine emulsion matrix are characterized by high detonation ability. Critical diameter (as minimum diameter when detonation occurs) and reaction zone length are known in the case of thin confinement with low acoustic impedance. The dependence of critical diameter of EMX in steel confinement with high acoustic impedance was examined in the range of initial density 0,75–1,37 g/cm3 . Density was varied by the concentration of glass microballoons, which were used as the sensitizer. It was shown experimentally, that characteristic value is /2 1 cr R d a  in the case of strong confinement. This can be due to the decrease of detonation front curvature. Comparison was made between the values of critical diameter in weak and strong confinement. The main distinction is that such dependence in strong confinement is lower and almost monotonic. This can indicate the influence of some processes besides lateral rarefaction wave. Period of reaction is closely connected with critical diameter and reaction zone length. Model based on heterogeneous kinetic of heating of emulsion surrounding single microballoon was proposed to describe the experimental dependence of the reaction zone time of EMX on concentration of microballons