Simulations of shock initiation of CL-20/HMX co-crystal
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摘要: 采用非平衡分子动力学方法模拟了CL-20/HMX共晶炸药冲击压缩和化学反应行为,获得了密度以及粒子速度的时空分布、冲击雨贡纽、冲击起爆压力、爆轰压力等数据,以及主要中间产物和稳定产物分布。模拟结果显示,共晶的初始分解路径是CL-20中N—NO2键断裂,主要稳定产物是N2、CO2和H2O。CL-20和HMX的分解速率随着冲击波速度的增加而增加,并且逐渐接近,但各冲击条件下CL-20分子的衰减速率均大于HMX。
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关键词:
- CL-20/HMX共晶 /
- 冲击波 /
- 冲击雨贡纽 /
- 化学反应
Abstract: The shock compression and chemical reaction behaviors of CL-20/HMX energetic co-crystal explosives were simulated by nonequilibrium molecular dynamics. The spatio-temporal distributions of density, particle velocity, shock hugoniots, shock initiation pressure, and detonation pressure were obtained. The distribution of main intermediate products and the stable products were also investigated. The simulation results show that the initial reaction pathway is N—NO2 cleavage to form NO2 from CL-20 in co-crystal, with N2, CO2 and H2O as the main products. The decomposition rate of CL-20 and HMX increases with the increase of shock wave velocity gradually, but the attenuation rate of CL-20 is higher than that of HMX under each shock condition.-
Key words:
- CL-20/HMX co-crystal /
- shock wave /
- shock Huguniot /
- chemical reaction
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表 1 各冲击条件下共晶中CL-20和HMX诱导时间和衰减速率比较
Table 1. Comparison of induction time and decay rate of CL-20 and HMX in co-crystal under different shock conditions
up /(km·s−1) τCL-20/ps τHMX/ps rd, CL-20 rd, HMX rd, CL-20/rd, HMX 1.5 0.800 0 2.100 0 0.004 0 0.001 1 3.636 4 2.0 0.254 0 0.800 0 0.016 0 0.002 3 6.956 5 2.5 0.100 0 0.400 0 0.062 0 0.031 0 2.000 0 3.0 0.052 0 0.300 0 0.160 0 0.114 0 1.403 5 3.5 0.049 0 0.160 0 0.234 0 0.205 0 1.141 5 4.0 0.001 0 0.150 0 0.289 0 0.278 0 1.039 6 -
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