Structure of a pulsating detonation front

Results are presented from experiments involving the recording of the reflection of a detonation wave in a mixture of nitromethane and acetone from a transparent sapphire window. It is shown that unexploded regions remain after reflection, despite a rise in temperature by 760–800 K and a pressure rise of 7.8 GPa. Lateral displacement of the luminous regions ceases. These results conflict with current thinking on the formation of reaction zones by the mechanism of adiabatic thermal shock, and they require correction of representations on pulsating detonation.