Fracture mechanism of a cylindrical shell cut by circumferential detonation collision

The failure mechanism of a cylindrical shell cut into fragments by circumferential detonation collision was experimentally and numerically investigated. A self-designed detonation wave regulator was used to control the detonation and cut the shell. It was found that the self-designed regulator controlled the fragment shape. The macrostructure and micro-characteristics of fragments revealed that shear fracture was a prior mechanism, the shell fractured not only at the position of detonation collision, but the crack also penetrated the shell at the first contact position of the Chapmen-Jouguet (C-J) wave. The effects of groove number and outer layer thickness on the fracture behavior were tested by simulations. When the thickness of the outer layer was 5–18 mm, it has little effect on fragmentation of the shell, and shells all fractured at similar positions. The increase of the groove number reduced the fracture possibility of the first contact position of the C-J wave. When the groove number reached 7 with a 10 mm outer layer (1/4 model), the fracture only occurred at the position of detonation collision and the fragment width rebounded.     

红外脉冲强光辐射产生技术研究

定向红外脉冲强光辐射技术是定向红外对抗中的关键技术,主要用来破坏敌方精确制导武器或C4I系统的红外传感器。本文进行了三种产生技术的研究,即爆炸激励惰性气体,多丝电爆激励惰性气体和多点同步爆燃药物。在同步爆燃产生技术的研究中,当有效载荷弹药为0.2kg时,在距离源50m处得到三个波段(1～3、3～5、8～12μm)的辐射强度为(2.00～3.55)×l05W／Sr,脉冲半高宽为约20ms的强红外辐射脉冲。     

采用扩展有限元法的线式爆炸分离装置裂纹扩展分析

为了提高线式爆炸分离装置的安全性,本研究基于扩展有限元法,通过创建二维和三维动态裂纹扩展模型,探索了线式爆炸分离装置在爆轰波作用过程中的动态裂纹扩展和止裂机理。研究表明,分离壳体的裂纹扩展路径独立于裂纹初始角度;不考虑载荷时序时,二维和三维动态裂纹扩展的主方向分别沿着分离壳体的径向和环向;考虑载荷时序时,受不同区域应力波的联合作用,三维裂纹沿环向扩展的同时会沿着轴向扩展,但裂纹的扩展均不会影响到止裂槽以外的结构。所提方法和相应结论可为线式爆炸分离装置设计提供参考。     

新型导爆索式爆炸零门设计及试验

为了增强爆炸零门在应用中的稳定性,降低对沟槽装药装填工艺的要求,以间隙零门为研究对象,提出了以导爆索代替部分沟槽装药结构的方法。对具有不同尺寸参数的导爆索、沟槽装药以及零门间隙进行组合试验,以期通过试验得到装填工艺简单且控制通道对信号通道作用稳定的装填物质组合。研究结果表明,通过对由导爆索构成的爆炸零门进行合理的参数配置,能够实现在提升零门装置稳定性的同时又保证其可靠性。     

不同网栅结构对MEFP成型影响的对比分析

为了研究不同形状网栅结构对形成的MEFP破片的影响,利用LS-DYNA动力有限元程序,采用Lagrangian方法,分别对十字形网栅切割式MEFP战斗部、星形线形网栅切割式MEFP战斗部、中心圆环形网栅切割式MEFP战斗部、井字形网栅切割式MEFP战斗部成型过程进行了数值模拟研究,并对影响各自破片成型及发散角的因素进行了分析研究。通过对不同方案网栅切割式MEFP速度及散布面积对比分析,结果表明:采用井字形网栅产生的破片集聚性优于十字形、星形线形和中心圆环形结构方案。     

高性能炸药综合性能的多维评估

基于欧几里得几何距离的概念,给出了一种炸药综合性能的多维空间评估方法。这种方法在确定炸药理想方案和最差方案的基础上,综合考虑了各种炸药方案与理想方案和最差方案的欧几里得几何距离,以此评估炸药综合性能。     

子母弹子弹引信爆炸物处理安全性研究

子母弹药的应用与发展带来了严重的未爆弹药问题。初步建立了评定未爆弹药危险性的数学模型,并从该模型出发,详细探讨了子弹引信爆炸物处理安全性的设计途径,以尽可能消除未爆弹药隐患。     

新型扫雷装药爆炸场特性分析及应用

基于爆破法扫雷爆破筒扫雷作用原理,设计了8.2 kg一次引爆型固态FAE扫雷装置。通过改变起爆位置和设置方式,多次野外近地面爆炸试验,采用反射压力传感器在装药正向与侧向离爆点不同位置进行压力测试,同时在正向测线压力传感器的对应位置设置某型防步兵地雷,得到爆炸场不同位置处的爆炸参数以及防步兵雷扫雷范围。结果表明:水平设置扫雷装药的扫雷范围明显大于垂直设置的装药,最佳炸高约为0.60 m;且其爆炸场正压区作用时间曲线呈“V”形,产物作用范围达63倍装药半径,与等当量的TNT的作用时间有明显的优势;本装置的扫雷范围约为目前扫雷爆破筒爆破扫雷范围的1.8～3.85倍,正向可靠扫雷范围可达其装药半径的77倍,侧向达69倍。由于该装药爆炸作用区域正压作用时间明显加长,因此有利于各种地雷的清除,是一种潜在高效的爆破法扫雷装药。     

A melt-cast Duan-Zhang-Kim mesoscopic reaction rate model and experiment for shock initiation of melt-cast explosives

A melt-cast Duan-Zhang-Kim (DZK) mesoscopic reaction rate model is developed for the shock initiation of melt-cast explosives based on the pore collapse hot-spot ignition mechanism. A series of shock initiation experiments was performed for the Comp B melt-cast explosive to estimate effects of the loading pressure and the particle size of granular explosive component, and the mesoscopic model is validated against the experimental data. Further numerical simulations indicate that the initial density and formula proportion greatly affect the hot-spot ignition of melt-cast explosives.     

Effect of the end cap on the fragment velocity distribution of a cylindrical cased charge

The prediction of the fragment velocity distribution of a cylindrical cased charge with end caps is one of the key issues to assess the damage efficiency of the warhead. However, limited work has been con-ducted to predict the fragment velocity distributions along the axis of cylindrical cased charges with end caps. This paper presents a study of the velocity distribution of fragments caused by the explosion of a cylindrical cased charge with end caps. The fragment velocity distribution and the end cap velocity were determined by an X-ray radiography method, and the axial fragment distribution was determined by witness plates. It was found that the velocities of fragments, especially near the edge, were increased when the end caps were added, and the position of maximum velocity is closer to the non-detonation end. The fragment velocities were increased, and the fragment projection range was decreased with the increase of the thickness of the end cap. A formula for fragment velocity distributions of a cylindrical cased charge with end caps, which is based on Huang's formula, was proposed by the theoretical analysis and data fitting and validated experimentally. The results indicate that the proposed formula is accurate in predicting the fragment velocity distribution along the axis of a cylindrical cased charge with end caps detonated at one end.