非均质固体炸药冲击起爆与爆轰研究进展

综述了非均质固体炸药的冲击起爆机制、宏细观反应流模型、中尺度/跨尺度及连续介质尺度数值模拟和冲击起爆试验及测试技术等研究进展,并总结作者团队近年来在该领域的研究成果;分析了该领域的未来发展趋势,旨在加深对非均质固体炸药冲击起爆爆轰物理机制的认识,为装药安全性研究提供方法和技术手段。指出非均质固体炸药冲击起爆物理响应过程复杂,往往由多种热点机制控制,现有反应速率模型考虑热点机制单一,无法适应冲击起爆过程的高保真计算。现阶段压力相关型反应速率模型虽然在一定范围内适应细观结构的变化,但无法描述复杂加载路径如多次加载和斜波-冲击复合加载下炸药脱敏或敏化、拐角效应死区现象等,而熵或温度相关型反应速率模型可较好地适应复杂加载,但未考虑细观结构响应机制。发展多热点机制耦合作用的、宽适应范围的宏细观反应速率模型是反应流模型的重要方向。快响应高分辨率的细观实验诊断技术一直是爆轰领域的技术难点,中尺度计算是现阶段冲击起爆热点机制研究的主要手段,已初步实现从中尺度到宏观尺度的冲击起爆跨尺度计算,仍是非均质固体炸药冲击起爆与爆轰问题数值模拟发展的重要趋势。附参考文献151篇。     

2，4-二硝基苯甲醚基熔铸含铝炸药冲击起爆特性

为钝感高能炸药安全性设计和应用提供理论依据和物理基础,深入开展钝感熔铸含铝炸药冲击起爆特性实验研究。建立蓝宝石飞片平面撞击加载炸药一维拉格朗日分析组合式电磁粒子速度计实验测试系统,测量2,4-二硝基苯甲醚（DNAN）基熔铸含铝炸药冲击起爆爆轰成长过程中不同拉格朗日位置的粒子速度-时间变化曲线,获得飞片撞击速度和固相炸药颗粒度等变化对其冲击起爆爆轰成长的影响规律,并确定了该熔铸含铝炸药的冲击Hugoniot关系（D=2.439+2.137u,D为冲击波传播速度,u为粒子速度）和未反应炸药状态方程参数。结果表明：DNAN基熔铸含铝炸药冲击起爆爆轰成长过程的典型粒子速度曲线呈驼峰状,冲击波阵面波后粒子速度明显上升并加速追赶前导波阵面,冲击起爆过程整体表现为加速反应特征;在该装药颗粒度级配范围和加载压力下,加载压力越高或固相炸药颗粒度越小,炸药冲击起爆爆轰成长越快,越早转为爆轰。     

不同厚度比陶瓷/金属复合装甲抗弹性能

为支撑陶瓷复合装甲的结构设计,研究不同厚度比陶瓷/金属复合装甲的弹道防护性能。通过陶瓷/金属复合结构抗侵彻性能弹道实验及数值模拟研究,完成有限元-光滑粒子流体动力学耦合计算模型的校验;模拟长杆弹撞击陶瓷复合装甲过程,分析装甲陶瓷与金属背板厚度比对界面击溃效应影响,获取不同厚度比陶瓷/金属复合装甲抗弹性能。研究结果表明：陶瓷复合装甲存在两种主要防护机制;当弹体速度小于1 000 m/s,随着陶瓷厚度从15 mm增加至25 mm,复合装甲的界面击溃驻留时间能够提高一倍以上,期间弹体耗能最高可达50%;当弹体速度大于1 000 m/s时,侵彻阶段的耗能占据弹体动能损失的主导,期间最高耗能可达85%;当金属与陶瓷的厚度比为2∶1时,复合结构使弹体具有较长的界面驻留时间,并实现较高的弹道防护效能。     

流体动力超声在火炸药生产中的应用展望

重点从与火炸药行业相关的降粘防蜡、萃取、乳化分散、雾化、洗涤等五个方面进行总结,提出了在火炸药行业应用的前景及可行性。在军民融合的大背景下,流体动力超声技术在火炸药的生产过程中将大有可为。     

HMX状态方程与弹性性能的分子动力学研究

利用COMPASS力场，采用NPT系综对β-HMX晶体进行了温度为295K，压力为0—27GPa的分子动力学模拟并进行静态力学分析。研究了β-HMX的压缩各向异性，得到了295K下β-HMX的等温线，用不同状态方程对结果进行拟合，求得了零压下β-HMX体积模量民及其关于p的一阶导数K＇0。计算结果表明，用不同方程拟合得到的K0和K＇0存在差异。通过静态力学分析，得到了弹性系数以及各模量随压力的变化情况，通过对G／K与C12-C44（柯西压）的研究发现JB-HMX的硬度随着压力的增大而增大，在大压力作用下材料由脆性到韧性转变。     

Detonation Shock Dynamics Relations for RDX-TNT Based Cast Explosives

RDX and TNT based explosives are very useful in performing research and development works especially when complex shaping of an assembly is required due to their molding capability and the range of ratios in which they can be mixed. In this paper, for these compositions, detonation shock dynamics (DSD) relations between normal detonation velocity Dn and detonation wave curvature κ are determined for RDX∶TNT explosives in weight ratios 40∶60, 50∶50 and 60∶40. Experiments are performed with 50 mm diameter rate sticks of approximately 200 mm length using high speed rotating mirror camera and time measurement probes. The results show that first order DSD relation is indeed representative of these explosives. The slope of this relation increases by increasing TNT contents in these explosives. Going from 40% to 60% TNT, the data show an increase of more than 100% in negative slope of Dn-κ relation.     

Numerical Simulations of Tungsten Alloy Rods Penetration into Alumina Ceramic/Armor Steel Composite Target

The Johnson-Holmquist constitutive ceramic model is re-implemented into the LS-DYNA3D program to simulate the penetration of long rod projectile into ceramic/armor steel composite targets. The damage evolution, fracture propagation, and spall damage in the ceramic/armor targets is represented during the simulation procedure and the accuracy of the penetration depth comparing between the simulating and experimental results is reliable with an error less than 8%. The relationship between the mass efficiency factor, differential factor and ceramic tiles thickness is given out for the penetration results with/without a cover plate.     

Numerical Simulation on Explosion in Double-Layer Medium of Concrete and Soil

The numerical simulation on explosion in concrete and soil is performed by using the three-dimension finite element code LS-DYNA, into which a continuum damage model which can well describe the fracture of concrete is implemented. As a consequence, wave propagation and attenuation in concrete and on soil-concrete interface are obtained respectively. Moreover, the damage regions of concrete at different thicknesses of soil （TOS） and depths of charge （DOC） are procured. The existent soil reduces damage region of concrete. Numerical results provide reference for design of warhead and protective structure and blasting.     

高聚物粘结炸药模拟材料动态变形破坏的实验研究

采用分离式霍普金森压杆(SHPB)加载装置对高聚物粘结炸药(PBX)模拟材料进行动态拉伸和压缩加载。利用高速摄影装置记录材料动态变形破坏过程,结合数字散斑相关技术,对不同加载条件下的位移场和应变场进行了分析,对PBX模拟材料动态变形破坏现象和机理进行了分析。实验结果和理论分析基本吻合,验证了数字散斑相关方法用于PBX模拟材料动态测量的可行性。