Re-initiation Processes of Detonation Wave Behind Slit-Plate (Visualization of Re-initiation and Quenching Processes of Detonation Wave)

Abstract

A propagation of detonation wave shows particularly interesting phenomena, since the detonation wave is constituted from a three-dimensional shock wave system accompanied with a reaction front. Thus, the passage of a detonation wave draws cellular patterns on a soot-covered plate. Pressure and temperature behind the detonation wave are extremely high and have a potential to cause serious damages around it. Therefore, it is necessary from safety engineering point of view to quench the detonation wave with short distance from the origin. In this study, experiments applied high-speed schlieren photography are conducted to investigate behaviors of the detonation wave diffracting from two pieces of slits. The detonation wave produced in a stoichiometric mixture of hydrogen and oxygen is propagated through the slits and behaviors behind slit-plate are experimentally investigated. As a result, when the detonation wave diffracted from the slits, a shock wave is decoupled with a reaction front. Since two shock waves progagated from the slits interact each other at centre behind the plate, the detonation wave is re-initiated by generating a hot-spot enough to cause local explosion. It is also clarified that the shock wave reflected from a tube-wall induces detonation re-initiation.