Structure of Detonation Waves in Mixtures of Tetranitromethane with Nitrobenzene and Methanol

Experimental studies of the structure of detonation waves in mixtures of tetranitromethane with methanol and nitrobenzene have been performed. Particle velocity profiles at the arrival of detonation waves at the interface with a water window were measured by a laser interferometer. It has been shown that the flow pattern in the reaction zone changes sharply at a concentration of diluents in the vicinity of stoichiometry, resulting in a decrease in the amplitude of the von Neumann spike up to its complete disappearance. The detonation waves are stable to the formation of a cellular structure of the front over almost the entire concentration range, except in the range near the limiting values. At the same time, the amplitude values of particle velocity show poor reproducibility from experiment to experiment performed under the same conditions. The obtained experimental dependences of detonation velocity on the concentrations of methanol and nitrobenzene are in good agreement with thermodynamic calculations.