多脉冲加载下PBX装药的应力放大效应  

Stress amplification effect of PBX charge under multi-pulse loading

作　　者：何杨 胡秋实[1] 仲苏洋 廖深飞 李涛[1] 傅华[1] HE Yang;HU Qiushi;ZHONG Suyang;LIAO Shenfei;LI Tao;FU Hua(Institute of Fluid Physics,China Academy of Engineering Physics,Mianyang 621999,Sichuan,China)

机构地区：[1]中国工程物理研究院流体物理研究所,四川绵阳621999

出　　处：《爆炸与冲击》2024年第6期26-38,共13页Explosion and Shock Waves

基　　金：中国工程物理研究院院长基金(YZJJZL2023014)。

摘　　要：针对弹体侵彻过程中装药常常受到多脉冲载荷作用的问题,提出了一种装药多脉冲加载装置,研究了多脉冲加载下装药的应力放大效应。基于集中质量法建立了多脉冲加载装置的等效弹簧模型,对产生应力放大的条件进行了探讨。结果表明,多脉冲载荷频率与装药固有频率匹配时系统发生共振,装药产生响应放大,放大倍数随结构间隙宽度的增加而降低。装药多脉冲加载下存在一个时间区间,撞击加载的发生时刻落在该区间内时系统可产生放大效果。对高聚物黏结炸药(polymer bonded explosive,PBX)模拟材料,实现了实验室条件下应力幅值百兆帕、脉冲间隔毫秒级、脉冲次数3次且幅值逐渐放大的多脉冲载荷加载。A charge is usually subjected to multi-pulse loading in the process of projectile penetration.A multi-pulse loading device for charge was proposed,and the stress amplification effect of the charge under multi-pulse loading was studied.An equivalent spring model of the multi-pulse loading device was established based on the lumped mass method.The amplification effect of the equivalent model was studied in the time and frequency domains.Based on the finite element analysis of the multi-pulse loading of the charge,the conditions for generating stress amplification were discussed.The results show that the system resonates when the multi-pulse load frequency matches the natural frequency of the charge,and the charge produces amplification response.The presence of gaps causes the main resonance frequency of the system to deviate towards the lower frequency range.The amplification factor decreases with the increase of the structural gap width.When the impact occurs near the moment when the T-shaped transmission bar and the limit block have just separated,the optimal amplification effect can be produced.Under three pulse loading conditions,the optimal amplification factor for the second and third impact is 1.7 times and 2.1 times,respectively.Multiple pulse loading experiments were conducted on Teflon and PBX explosive simulation materials.The relative motion of bullets,limit blocks,and T-shaped transmission bars was observed using high-speed photography technology.The sample pressure was measured using a PVDF(polyvinylidene fluoride)pressure gauge.The results show that stress amplification occurs when the bullet and the T-shaped transmission bar collide in the same direction,but there is no amplification effect when they collide in the opposite direction,which is consistent with the numerical simulation results.Under the condition of constant total length,the stress amplification factor of the combination of Teflon and PBX simulation material is smaller than that of Teflon due to the presence of interface gaps.

关 键 词：侵彻 多脉冲 应力放大 集中质量法 PBX炸药 

分 类 号：O389[理学—流体力学]