Abstract:
The methodology of calculating the problem of detonation initiation in acetylene-oxygen mixtures by a small-diameter sphere flying with a velocity greater than the Chapman–Jouguet detonation velocity is presented. A reduced kinetic scheme of chemical reactions is tested against experimental data on the ignition delay time, detonation propagation velocity, and detonation cell size. Regimes of oblique detonation and combustion in an acetylene-oxygen mixture diluted by argon are obtained in experiments in the pressure range from 21.1 to 60.7 kPa. The energy of detonation initiation by a high-velocity projectile is estimated, which demonstrates good agreement between analytical, numerical, and experimental data. Based on this estimate, the initiation of oblique detonation by a high-velocity projectile in an acetylene-oxygen mixture is calculated. A correlation between the numerically predicted flow regimes and analytical estimates is obtained.
