摘要
为了研究冲击波和破片撞击复合作用下装药点火机理,采用先冲击波损伤装药、后破片撞击已损伤装药的实验方法,获得受冲击装药点火对应的破片临界撞击速度为446.9~449.4 m·s~(-1)。采用LS?DYNA程序,基于节点约束?分离法对装药冲击波损伤进行数值模拟,而后用完全重启动方法对冲击损伤装药在破片撞击下的点火反应过程进行二次模拟,通过"升?降"法得到受冲击损伤装药点火对应的破片临界撞击速度为452~453 m·s~(-1),实验和数值模拟结果吻合较好。结果表明,可采用节点约束?分离方法和完全重启动数值模拟技术进行冲击波和破片复合作用下装药点火数值模拟;受冲击波损伤装药的破片撞击点火临界速度明显要低于未损伤装药,装药受损伤状态对破片撞击感度起到了敏化作用,从而降低了破片撞击点火的临界速度。
To study the ignition mechanism of charge under the combined action of shock wave and fragment impact,the critical impact velocity of fragment corresponding to the ignition of impacted charge obtained by the experimental method of first com ?pacting charge by shock wave and then impacting damaged charge by fragment was 446.9-449.4 m·s~(-1). LS?DYNA program was used to numerically simulate the shock wave damage of charge based on the nodal constraint?separation method. Then,second?ary simulation to the ignition reaction process of impact damaged charge under fragment impact was performed by full restart method. The critical impact velocity of fragment corresponding to the ignition of impact damaged charge obtained by"up?down"method is from 452 m ·s~(-1) to 453 m ·s~(-1),the experimental and numerical results are in good agreement. Results show that the nodal constraint?separation method and the full restart numerical simulation technology can be used to simulate the ignition of charge under the combined action of shock wave and fragments,the critical velocity of fragments impact ignition of charge dam ?aged by shock wave is lower than that of non?damaged charge,and the damaged state of charge sensitizes the impact sensitivity of fragments. This reduces the critical velocity of fragment impact ignition.
引文
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