飞秒激光作用下RDX/HTPB混合炸药界面反应的分子动力学模拟  

Molecular Dynamics Simulation of RDX/HTPB Mixed Explosives Interfacial Reaction Under Femtosecond Laser

作　　者：伍俊英[1] 吴姣姣 李钧剑 尚伊平 方汇璇 陈朗[1] WU Junying;WU Jiaojiao;LI Junjian;SHANG Yiping;FANG Huixuan;CHEN Lang(State Key Laboratory of Explosion Science and Technology,Beijing Institute of Technology,Beijing 100081,China)

机构地区：[1]北京理工大学爆炸科学与技术国家重点实验室,北京100081

出　　处：《北京理工大学学报》2023年第4期329-340,共12页Transactions of Beijing Institute of Technology

基　　金：爆炸科学与技术国家重点实验室(北京理工大学)开放基金项目(KFJJ20-04M)。

摘　　要：为研究混合炸药在飞秒激光作用下界面上的反应特征,构建了RDX/HTPB混合炸药体系的计算模型,基于ReaxFF-lg反应力场,对其在飞秒激光作用下的响应过程进行了反应分子动力学模拟,分析了计算体系的温度、密度变化以及界面上的化学反应特征.结果表明:从HTPB和RDX两端加载激光能量时,RDX/HTPB体系界面上没有明显的温度突变,温度呈现平稳过渡的变化趋势.激光能量越高,HTPB和RDX反应越剧烈,在界面上HTPB分解产生的H或C原子与RDX分解的小分子产物发生化学反应,生成了CO、C_(3)O、C_(2)O_(2)、C_(2)HO、NH_(2)、NH_(3)等中间产物和H_(2)O、CO_(2)、H_(2)等终态产物;激光能量较低时,RDX和HTPB各自反应不充分,RDX区域仍有大量未分解的环状分子存在,HTPB区域主要是长碳链形式的大分子,两者界面区域分解产物间发生的反应较少.In order to have a better understanding of the reaction on the interface of mixed explosives under the femtosecond laser,a simulation model of the RDX/HTPB mixed explosive was constructed.Based on the ReaxFF-lg reaction force field,reaction molecular dynamics simulations were carried out under different laser loading conditions.The temperature and density variation of the system and the reaction characteristics at the interface were analyzed.The results show that when the laser energy is loaded from both ends of HTPB and RDX,there is no sharp temperature change at the interface of RDX/HTPB system.The higher the laser energy,the more violent the reaction between HTPB and RDX.At the interface,the H or C atoms generated by the decomposition of HTPB react with the small molecular products decomposed by RDX to form intermediate products such as CO,C_(3)O,C_(2)O_(2),C_(2)HO,NH_(2),NH_(3),and final products such as H_(2)O,CO_(2),and H_(2).When laser energy is low,the reactions of RDX and HTPB are insufficient.There are still lots of undecomposed cyclic molecules in the RDX region,and HTPB region is mainly macromolecules in the form of long carbon chains,and the reaction between the decomposition products of RDX and HTPB in the interface region is insignificant.

关 键 词：RDX/HTPB混合炸药 飞秒激光 分子动力学计算 ReaxFF-lg力场 

分 类 号：TJ55[兵器科学与技术—军事化学与烟火技术]