高密度压装炸药燃烧转爆轰研究

Investigation of the Deflagration to Detonation Transition in Pressed High Density Explosives

为了给高密度炸药装药的安全性分析提供更准确的依据,在不同约束条件下(DDT管长420 mm,壁厚分别为10,20 mm),进行了PBXC03压装炸药燃烧转爆轰实验,采用电离探针测量了炸药中反应波速度,通过观测管体和反应波速度变化,判断炸药燃烧转爆轰(DDT)的情况。根据高密度炸药状态,建立了炸药燃烧转爆轰计算模型,采用燃烧反应速率方程,描述炸药反应过程。应用网格分离和节点随机失效方法计算高温高压炸药反应产物作用下管体的膨胀和破裂,考虑气体产物泄漏,压力下降对炸药反应的影响。对不同约束条件下(DDT管长420 mm,壁厚分别为5,10,20,30 mm)炸药燃烧转爆轰过程进行了数值模拟计算。结果表明:PBXC03压装炸药只有在强约束下(壁厚30 mm)才能够发生燃烧转爆轰,弱约束下(壁厚5 mm)管体破坏引起气体泄漏和压力降低是限制炸药燃烧转爆轰的主要原因。

In this work,deflagration to detonation（DDT） experiments of pressed PBXC03 with different confinements（shell length 420 mm,shell thickness 10 mm and 20 mm） were conducted.Electrical pins were used to measure reaction wave velocity in explosives.DDT intensity was estimated by observing shell fragments and analyzing velocity changes.According to the conditions of different high density explosive charge,a DDT calculating model was established.The explosive deflagration reactive flow model was adopted to describe explosive reaction process.The methods of separating elements and random invalidation stress were used to describe shell expansion and rupture.The effects of gas leakage and pressure reduction on explosive reaction were considered.DDT processes under different confinements（shell length 420 mm,shell thickness 5,10,20,30 mm） were calculated.The results show that only high density PBXC03 with strong confinement（shell thickness 30 mm） may undergo DDT.Gas leakage and pressure reduction induced by weak confinement（shell thickness 5 mm） will restrict the occurrence of DDT.