铸装TNT/RDX爆轰过程导电性及反应区厚度实验

利用冲击起爆方式改进了炸药爆轰过程电导率的同轴测试方法,推导出其电导率计算公式.采用输入冲击波压力匹配的方法减小了反应区内波的反射作用和爆轰成长过程的不稳定性对其电导率的影响,进而测得铸装TNT炸药和TNT/RDX混合炸药爆轰过程中随时间变化的电导率曲线.通过分析曲线中拐点出现的原因,推导出炸药的化学反应时间和反应区厚度.研究结果表明,RDX的增加会降低铸装TNT/RDX炸药的最大电导率;得出铸装TNT炸药的化学反应时间约为0.08 μs,反应区厚度约为0.41 mm;几种铸装TNT/RDX炸药的反应区厚度均在0.5 mm附近.     

射流冲击盖板覆盖下有限厚炸药的仿真和试验研究

为了研究有限厚炸药在射流冲击下的起爆过程,并得到有限厚炸药的临界起爆阈值。试验采用Φ40 mm聚能装药作为射流源,通过高速录像进行拍摄,对不同厚度的50SiMnVB盖板覆盖下的43 mm厚TNT炸药进行了射流冲击起爆试验,得到炸药的临界起爆阈值和不同刺激强度下的响应情况以及反应产物的膨胀速度。采用数值仿真软件进行了有限厚炸药在射流冲击下的数值模拟计算,得到了射流冲击下炸药内弯曲冲击波发展过程以及有限厚炸药的临界起爆阈值和炸药厚度关系,并通过试验结果进行了验证。最后建立了有限厚炸药临界起爆阈值和临界盖板厚度的计算模型。结果表明:厚度43 mm的TNT临界起爆阈值为37 mm3·μs^-2,并且在不同响应之间反应产物的膨胀速度相差至少一个数量级。射流冲击有限厚炸药时,弯曲波发展为爆轰波需要一定距离,剩余射流头部速度越高,弯曲波发展为爆轰波所需的距离越短。炸药厚度的减少将导致有限厚炸药的临界起爆阈值和临界盖板厚度的增加,并且有限厚炸药的临界起爆阈值的对数与炸药厚度的对数近似呈线性关系。     

不同加载压力下炸药冲击起爆过程实验和数值模拟研究

采用炸药平面透镜爆轰加载及空气与隔板综合衰减技术,建立基于锰铜压阻传感器的 一维拉格朗日实验分析系统,得到了3 种加载压力下两种颗粒度PBXC03 炸药冲击起爆不同拉格 朗日位置的压力历史,以及加载压力对炸药冲击起爆过程的影响规律。采用DYNA2D 程序,对两 种颗粒度PBXC03 炸药的冲击起爆过程进行数值模拟,计算结果与实验结果趋势一致。结果均表 明:加载压力减小,炸药中前导冲击波速度增长变慢,压力增长变缓,炸药的到爆轰距离增加。数值 模拟得到的两种颗粒度PBXC03 炸药起爆压力和到爆轰距离的关系与文献[15] 的POP 图曲线吻 合较好,验证了文献[14]建立的PBX 炸药冲击起爆细观反应速率模型的合理性。     

钝感HNS-IV 炸药飞片冲击起爆数值仿真

为获得HNS-IV在飞片冲击下的窄脉冲宽度的起爆特性,使用Lee-Tarver点火增长模型和有限元分析软件,对不同直径、厚度的聚酰亚胺飞片撞击HNS-IV炸药过程进行数值模拟.按照试验装置的设计方案,建立数值模拟模型,对不同直径、厚度飞片冲击起爆HNS-IV炸药的机理及影响规律进行分析.仿真结果表明:在飞片厚度一定的条件下,飞片直径增大相应的引爆阈值压力和引爆阈值速度减小;在飞片直径一定的条件下,随着飞片厚度的增加,炸药的引爆阈值压力和引爆阈值速度减小;随着炸药密度的降低,炸药阈值引爆的飞片速度也随之减小.对于HNS-IV炸药,计算所得引爆阈值压力和脉冲持续时间经拟合后所得曲线满足constnpτ=的判据,确定其临界起爆能量.     

常温附近温度变化对炸药冲击起爆特征的影响（英）

为了研究常温附近温度变化对炸药冲击起爆特征的影响程度和规律,设计并建立了炸药局部加热和冷却装置,结合拉氏分析方法研究了HMX/TATB基复合高能炸药PBX-1和TATB基钝感高能炸药PBX-2在常温附近(5～75 ℃)的冲击起爆压力成长过程.基于实验结果,利用点火增长模型对两种炸药的冲击起爆过程进行了数值模拟.结果表明,随着温度升高(5～75℃),炸药的冲击起爆压力成长过程均逐渐变快,到爆轰距离变短,点火增长模型中的反应速率参数G1变大,说明两种炸药随温度的升高对冲击变得更敏感,常温附近温度变化对炸药安全性的影响不能忽略.     

含TNT注装混合炸药爆轰产物电导率实验研究

改进了炸药爆轰产物电导率的同轴测试系统,测量了TNT注装炸药中加入RDX、Al、KCl等药剂后爆轰产物的平均电导率,得出了不同RDX含量的TNT/RDX炸药平均电导率最大值变化曲线.结果表明:TNT中加入RDX后会减少其爆轰产物的电导率,而加入Al后TNT炸药爆轰产物的电导率明显高于不含Al炸药,加入5% Al粉平均电导率最大值即可增大4倍以上.另外,加入KCl也会增大TNT/RDX混合炸药的电导率.     

引信飞片起爆多方案动态特性仿真对比

针对引信传爆管输出飞片远距离引爆弹丸主装药优化设计问题,应用ANSYS/LS-DYNA软件研究了12种飞片起爆方案,模拟出炸药驱动飞片起爆过程,并得出不同形状、不同厚度飞片冲击起爆炸药时炸药端面爆轰压力与时间的曲线。结果表明:在飞片厚度设计经验范围内,平板型飞片冲击炸药的爆轰压力随飞片厚度增加而增大;碟型飞片冲击炸药的爆轰压力随飞片厚度增加而减小;锥型飞片越厚越不易引爆炸药,而球缺型飞片越薄越不易引爆炸药,并且对飞片厚度极为敏感。     

六棱柱破片冲击起爆带壳B炸药速度阈值研究

文中根据六棱钨柱破片冲击起爆带壳B炸药实验,利用Autodyn-3D软件进行仿真.B炸药应用点火增长Lee-Tarver模型,得出炸药压力云图以及B炸药内部观测点压力变化曲线,仿真数据与实验结果吻合.在此基础上计算出六棱柱最大迎风面积及其冲击起爆阈值速度,得出双六棱柱破片不同间距与阈值速度的关系和单破片冲击不同盖板厚度阈值速度曲线.研究结果对反导战斗部破片杀伤元素的设计具有指导意义.     

常温附近温度变化对炸药冲击起爆特征的影响（英文）

为了研究常温附近温度变化对炸药冲击起爆特征的影响程度和规律,设计并建立了炸药局部加热和冷却装置,结合拉氏分析方法研究了HMX/TATB基复合高能炸药PBX-1和TATB基钝感高能炸药PBX-2在常温附近(5~75℃)的冲击起爆压力成长过程。基于实验结果,利用点火增长模型对两种炸药的冲击起爆过程进行了数值模拟。结果表明,随着温度升高(5~75℃),炸药的冲击起爆压力成长过程均逐渐变快,到爆轰距离变短,点火增长模型中的反应速率参数G_1变大,说明两种炸药随温度的升高对冲击变得更敏感,常温附近温度变化对炸药安全性的影响不能忽略。     

某小口径弹丸穿甲与静爆引爆TNT炸药研究

为了评价某小口径多用途弹丸的冲击起爆能力,采用分步试验,结合ANSYS LS-DYNA动力学分析软件,对该型弹丸的冲击起爆能力进行了研究.通过调整弹丸半径方向网格数量 λ,建立了有效的弹丸穿甲计算仿真模型.对比仿真计算与试验结果,表明网格划分对计算结果精度影响较大.当 λ>12时,仿真计算的临界击穿速度与试验值基本一致.在弹丸能够穿透钢板的基础上,对弹丸静态引爆炸药盒的试验研究,验证了该型小口径榴弹的冲击起爆TNT炸药能力.     

Nitrosation and Nitration of Tetraacetyldibenzylhexaazaisowurtzitane

Tetraacetyldibenzylhitane (TADBIW) was subjected to debenzylation by nitrosating with inorganic materials available commercially to synthesize tetraacetyldinitrosohexaazaisowurtzitane (TADNSIW). TADNSIW was purified, and its structure was determined by FTIR, 1H NMR, MS and element analysis. The debenzylation reaction of TADBIW gave quantitative benzaldehyde as a by-product. This indicates that the reaction produces an imine cation as an intermediate. Hexanitrohexaazaisowurtzitane (HNIW) was prepared from unpurified TADNSIW with the yield over 96.0 % and the purity more than 98.0 %. And the mechanism of the reaction from TADNSIW to HNIW is proposed to be oxidation of nitroso and nitration of acetyl on the molecule of TADNSIW, This reaction system involved is simple, and the reaction can complete within a short time and under mild conditions. The product can be easily to separate and the waste disposed readily.     

A Robust Algorithm for Watermarking 2D Vector Maps with Low Shape-Distortions

The technique of watermarking has been introduced into 2D vector maps for many potential applications such as protecting the copyright of important GIS （geographical information system） data and tracing the data source of military maps. In most previous works, although the validity of the map data could be preserved during the embedding procedure, the shape-distortions of the map elements are usually neglected which would tend to degrade the invisibility of the watermarking schemes. A shape-preserving algorithm for watermarking 2D vector maps is presented in this paper. A 1D distance sequence extracted from the original map is adopted as the cover data instead of 2D coordinates. A watermark bit is represented by changing the distributions of the cover data. The embedding procedure induces lower shape-distortions than in former works. Experimental results indicate better invisibility of the proposed scheme, as well as its robustness to certain attacks such as map simplification, interpolation, additive noise and most geometric transforms.     

Open Rule-setting System Applied to Conceptual Design of Engines

Open rule-setting method advanced in this paper concentrates on providing designers of engines with a convenient way to express their design innovations and develop the expected prototypes in the early CAD stage, and constitute effective models for the following analysis process of CAE and CAPP. The problems arisen in the process of conceptual design with the traditional experience-based development method are analyzed. Based on those analyses, open rule-setting method is presented and some associated technical problems are discussed. The functional framework of open rule-setting system was built as software engineering methods. The speciality of the engine product as a kind of complex product and the requirement of the engine product based on its structural particularity to rule-setting system are considered carefully. A demonstration is supplied to illustrate how the open rule-setting method enhances the efficiency and quality of the engine conceptual design.     

Research on Linux Network Device Driver

By analyzing the working principle of Linux network device driver, discussing the Linux network driver structure and its key technologies, the general network driver structure and its design methodologies in Linux system are summarized. Through modifying the network device driver of Linux device driver 3rd version snull, c and improving the COW technology, the Zero-Copy technology in Linux （kernel version 2.6.11 ） is implemented. In the end, the success test tells us that the thorough analysis of network device driver is the foundation of many applications, and it also provides a certain improvement to a lot of real applications, even to military application development.     

Improvement and Experiment of the Reamer in Vibra Cutter Against Wave Edge of Titanium Sheet Alloy Parts

By analyzing the influencing factors of part quality making of sheet alloy of titanium by vibra cutter, the shape of upper reamer is set as cylinder and wedge-shaped form, and the lower reamer as plain and hemicycle form, and its main structural parameters are defined as well. Then it is validated further that such improved vibra cutter reamer can be used to process curve-edged parts of titanium alloy sheet. The experimental result shows that the titanium alloy sheet parts processed by above equipment have no sharpen angles for convex parts and evident crevasse of concave-edged part. In summary, such improvement can eliminate the free-waved edge and improve the manufacture quality of titanium alloy sheet parts greatly.     

Experimental Study on the Small Flyer Initiating Behavior of Fine-grained Explosives

The initiating behavior of fine-grained explosives by small flyer is studied. The diameter of small flyer in this device is 1 ram. The test results indicate that the granularity of explosives has great effect on its flyer initiating sensitivity.The flyer initiating sensitivity of the fine-grained explosives is higher and the critical initiating energy is lower than that of common explosives. For common explosive, the flyer initiating sensitivity increases as the density is reduced. But for the fine-grained explosive, the test results are exactly opposite.     

Algorithm for Multi-laser-target Tracking Based on Clustering Fusion

Multi-laser-target tracking is an important subject in the field of signal processing of laser warners. A clustering method is applied to the measurement of laser warner, and the space-time fusion for measurements in the same cluster is accomplished. Real-time tracking of multi-laser-target and real-time picking of multi-laser-signal are introduced using data fusion of the measurements. A prototype device of the algorithm is built up. The results of experiments show that the algorithm is very effective.     

Robust Graded Sliding Mode Tracking Control for Low Speed Spinning Ballistic Missiles

The nonlinear dynamic model of spinning ballistic missiles is established during the first boosting phase of the missile. Based on the conventional backstepping sliding mode control and the assumption of a two time-scale separation of missile dynamics, a graded sliding mode controller is designed with two sub-sliding surfaces which have invariability to external disturbances and parameter perturbations, and a matrix which comprises three first order low pass filters is introduced to prevent ＂explosion of terms＂. Owing to the upper bounds of the uncertainties are difficult to obtain in advance, adaptive laws are introduced to estimate the values of the uncertainties in real-time. Eventually, the numerical simulation results given to show the proposed controller can ensure the steady flight of missiles.     

A Study on the Estimation of Aeroheating upon the Warhead Nose at Supersonic Speed

An expression for estimating the aeroheating on a warhead nose at different supersonic speeds is proposed by incorporating CFD （computational fluid dynamics） and the least-square method. Compared with the traditional estimation formula, the expression is more accurate, convenient and can be used in the optimized design of warheads. The error from the result obtained in the test of a ball cartridge flight is less than 3 %. It satisfies the engineering requirements.     

Influence of Installing Error on the Surface Shape Precision of the Axial Symmetry Aspheric Workpiece in Lapping

A method to calculate the surface shape error, which is caused by the installing error between the workpiece and the lapping tool in the process of form lapping, is proposed. The mathematical model which the installing translation error influences on the workpiece surface shape error is established. The changing rule of the error is simulated through the calculating example of the paraboloid workpiece. The results indicate that the surface shape error of the workpiece is increasing with the increase of the installing translation error, it is also increasing gradually along the center point of the curve surface to the edge, and the influence is severer to the curve surface with great curvature than that of the small curvature when the translation error is the same.