初始自由空腔体积对PBX-3炸药慢烤反应烈度的影响  

Influence of Initial Free Cavity Volume on the Reaction Violence of PBX-3 in Slow Cook-off

作　　者：胡平超[1] 李涛[1] 刘仓理[2] 傅华[1] 薛洪 胡顺治 HU Ping-chao;LI Tao;LIU Cang-li;FU Hua;XUE Hong;HU Shun-zhi(Institute of Fluid Physics,China Academy of Engineering Physics,Mianyang 621999,China;China Academy of Engineering Physics,Mianyang 621999,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 [2]中国工程物理研究院,四川绵阳621999

出　　处：《含能材料》2023年第10期1035-1040,共6页Chinese Journal of Energetic Materials

摘　　要：为了认识初始自由空腔对约束奥克托今(HMX)基PBX-3炸药慢烤反应烈度的影响,以圣地亚热点火(SITI)实验装置为参考,设计了初始自由空腔体积率分别为1.0%和7.4%的弱约束慢烤实验装置。在相同的温升速率下开展了约束HMX基PBX-3炸药慢烤实验,通过小尺寸K型热电偶测量炸药中心平面不同位置以及壳体表面的温度变化历程,采用耐高温光子多普勒测速探头测量炸药热爆炸后壳体的运动速度,并在慢烤箱中回收实验装置残骸。结果表明:在相同的壳体约束强度和加温条件下,2种不同初始自由空腔体积率的约束PBX-3炸药均在中心区域首先发生点火反应;初始自由空腔体积率为1.0%时,热爆炸时刻壳体表面的温度更高,炸药整体温度更高,炸药点火反应后壳体加速更快、速度更高,实验装置残骸碎片更小,反应烈度更高。分析认为:初始自由空腔体积率为1.0%时,热爆炸前炸药受到的应力更大,炸药损伤更严重;炸药中心点火反应后,更大的热应力使得炸药点火反应产生的气体在中心聚集形成更高的压力,炸药燃烧速率更大,燃烧产生的高温气体更容易进入微裂纹,形成更强的对流燃烧,导致压力增长速率更快,炸药反应更剧烈。In order to understand the effect of initial free cavity on the violence of confined octogen(HMX)-based PBX-3 in slow cook-off,the weak restricted test setup was designed with initial free cavity volume ratios of 1.0% and 7.4%,respectively,referring to Sandia instrumented thermal ignition(SITI).The confined HMX-based PBX-3 explosives were heated at the same rate in slow cook-off tests.The temperatures of different locations at the center plane of explosive and shell surface were acquired using small-sized K type thermocouples,the shell velocity after thermal explosion was measured using the heat-resistant probe of photonic-Doppler-velocimeter(PDV),and the wreckage of test setup was recycled in the slow cook-off chamber.The results show that the confined PBX-3 explosives are ignited in the center region for the same restricted strength and heating process,no matter with the initial free cavity volume.When the initial free cavity volume ratio is 1.0%,the shell surface temperature and the overall temperature of the explosive are higher when thermal explosion occurs,the shell accelerates faster and the maximum velocity is higher after thermal explosion,the wreckage fragments of test setup are smaller,and the reaction violence is higher.It is analyzed when the initial free cavity volume ratio is 1.0%,the stress of explosive is larger before thermal explosion,resulting in more serious damage.When thermal ignition occurs at the center of the explosive,the larger thermal stress causes a higher pressure induced by the gas accumulation,and the burning rate of explosive is higher.The high-temperature gas generated by the combustion is easier to enter the microcracks,resulting in stronger convective burning,faster pressure growth rate and more violent reaction.

关 键 词：自由空腔体积 反应烈度 热爆炸 慢烤实验 炸药 

分 类 号：TJ55[兵器科学与技术—军事化学与烟火技术]