PBX-9404炸药临界起爆特性数值模拟

Numerical simulation of critical initiation characteristics of the explosive PBX-9404

为研究PBX-9404炸药临界起爆特性问题,建立卡式隔板试验的冲击起爆计算模型,采用AUTODYN数值模拟软件和Lee-Tarver点火增长模型,对PBX-9404炸药在冲击波的作用下的临界起爆特性进行数值模拟。利用模拟计算与文献验证方法确定适合描述该试样炸药冲击起爆过程的Lee-Tarver模型参数,通过模拟计算冲击波在有机玻璃中的传播过程与实验对比的方法验证数值模拟的准确性。数值模拟结果表明:通过改变隔板材料、壳体厚度、点火方式等3种途径,冲击阻抗大的隔板材料临界隔板值小;壳体厚度越大,试样炸药的临界隔板值越大,临界起爆压力越小,当厚度值增加到5 mm后,两者不再变化;在3种点火方式里,点起爆的临界隔板值最小,面起爆的最大。

In order to study the critical initiation characteristics of the explosive PBX-9404,this paper establishes a calculation model of shock initiation of cartridge diaphragm tests.The critical initiation characteristics of PBX-9404 are numerically simulated under the action of shock wave by using AUTODYN numerical simulation software and Lee-Tarver ignition growth model.The Lee-Tarver model parameters suitable for describing the shock initiation process of the sample explosive are determined by using the methods of simulation calculation and literature verification.The accuracy of the numerical simulation is verified by simulating the propagation process of the shock wave in plexiglass and experimental comparison.The numerical simulation results show that,by changing the clapboard material,shell thickness and ignition mode,the critical clapboard value of the clapboard material with a large impact impedance is small.The larger the shell thickness is,the larger the critical clapboard value of the sample explosive is,and the smaller the critical initiation pressure is;when the thickness value increases to 5 mm,the two will not change.In the three ignition modes,the critical clapboard value of point initiation is the smallest and that of surface initiation is the largest.