关键词: 发射药燃烧;燃烧化学动力学;冲击波引爆;火焰传播

Abstract: The mechanism and sensitivity of deflagration to detonation transition(DDT) in highly packed granular propellant beds confined in steel tube have been experimentally studied for D-45,S-14,and 3/1 propellants.The compressive wave andflame front in the DDT processes were monitored by strain gages and ionization probes,respectively.By separating the compressive wave front and the combustion wave front,it was found that the compressive wove formed in the burning region behind the flamefront,with the increase of its strength and velocity,would overtake the flame front andforms a strong shock wave to initiate the detonation.The analysis for the experimentaldata showed that a rapid pressure increase near the ignitor was a necessary condition forthe formation of the compressive wave,which could explain the difference in DDT characteristics of the three propellants mentioned above.The influence on DDT characteristics of the experimental parameters(propellant properties,loading density,confinement) has also been investigated.

Key words: Gun propellant combustion;Combustion chemical kinetics;Shockwave initiation;Flame propagation