One-Dimensional Detonation Initiation

The x-t observation of one-dimensional initiation behind a reflected shock wave in hydrogenoxygen-argon mixtures is extended to include simultaneous density measurement using an optical interferometer. The wave pattern observed experimentally is reproduced theoretically using a nonsteady method-of-characteristics analysis with reasonable postulates for the reaction kinetics and shock heating. The close agreement between the theoretical and experimental results shows that in this case the initiation occurs as the result of an adiabatic explosion wave generated by reflected shock heating. The usefulness of this concept of initiation in understanding the mechanism of other initiation phenomena is discussed briefly.