Quasi-stationary reaction zone in gaseous detonation

The hydrodynamic structure of an exothermic reaction zone behind shock fronts close to one-dimensional ones has been studied. The shock tube operated by impulse piezo gauges and interferometer technique, in “compensating” regime for sufficiently long induction zones, was used for measurements. Two kinds of flow patterns were examined in experiments to avoid “spinning” effects: supported incident waves in the constant-area tube, and self-sustaining detonations in the gas preheated by shock waves to high temperatures. The induction-time data and the density profile in oxyhydrogen and oxymethane mixtures were analyzed on the basis of the kinetic data obtained by reflected wave technique and by similar methods. Some explanations of the sufficiently stable one-dimensional detonation waves realized in gas heated to 650°–850°K ahead of the shock front have been considered. Low-shock Mach numbers of the detonation wave in heated gas, and corresponding decrease of the pressure and energy jumps, are of particular interest. The influence of the ignition condition on the “spinning” regime appearance and its development is noted.