药片剪切试验中PBX-2炸药的响应特性

采用ANSYS/LS-DYNA有限元计算程序模拟设计了药片剪切试验装置,研究了Φ20 mm×5 mm和Φ20 mm×9 mm两种厚度的PBX-2药片在剪切试验中的响应特性。采用锰铜压力计测试样品中压力的变化过程,通过高速录像照片分析了撞击点火反应过程,用冲击波超压传感器测量了炸药的反应超压,综合分析了PBX-2炸药在药片剪切试验中的响应规律。结果初步表明,药片剪切试验中PBX-2炸药厚度由5 mm变化至9 mm,其反应落高阈值由3.5～3.7 m降低为3.0～3.1 m,即随着该炸药厚度增加,其反应落高阈值略有降低。     

不同升温速率热作用下PBX-2炸药的响应规律

采用不同升温速率3,5,10,25,105℃.min-1分别对PBX-2炸药进行了烤燃试验,试验中用热电偶分别测试样品半径处和中心处的温度变化过程,通过冲击波超压测量分析了样品的反应程度,根据热分析和烤燃试验结果宏观上分析了PBX-2炸药在热作用下的响应规律。试验结果初步表明:热作用试验中PBX-2炸药随着升温速率升高反应程度降低。采用Arrhenius模型对PBX-2炸药在热作用下响应进行了数值模拟,模拟的炸药温度变化结果与试验测试结果基本一致。     

PBX-2炸药加热条件下燃烧转爆轰特性

为了研究炸药在加热前后的燃烧转爆轰特性变化,设计了加热条件下燃烧转爆轰试验加载系统,对Φ30 mm ×400 mm的PBX-2炸药进行了试验。试验中采用热电偶测试装置壳体和炸药表面温度变化过程,采用离子探针测量了燃烧转爆轰过程的传播时间和距离,探讨了加热与未加热PBX-2炸药的燃烧转爆轰特性。结果表明,与未加热相比,加热至85℃时PBX-2炸药更难以发生燃烧转爆轰现象。     

压缩剪切作用下PBX的响应特性

为了研究高聚物粘结炸药(PBX)在压缩剪切作用下的响应特性,采用设计的压缩剪切试验装置,对Φ20 mm×40 mm的PBX-932和PBX-C43在22~57 m·s-1撞击速度范围内进行了响应试验。试验中采用压力计测试了压力变化过程,通过高速录像照片分析了撞击过程,采用冲击波超压传感器测量了炸药的反应超压,分析了两种炸药的响应特性。结果表明,随着撞击速度增加,两种PBX炸药的损伤度增加。在压力160~400 MPa,脉宽1.5 ms的压缩剪切作用下,PBX-C43和PBX-932的撞击速度阈值分别为25.5~27.7 m·s-1和22.7~24.4 m·s-1。两种炸药的反应程度基本一致。     

用抛射弹撞击法(Steven试验)研究PBX-2炸药加速老化前后反应能力

采用2kg弹丸对55℃加速老化180天和540天的PBX-2炸药进行了Steven试验,试验中采用锰铜压力计测试了样品中的压力变化过程,通过高速录像照片和压力曲线分析了炸药点火反应的延迟时间,通过冲击波超压传感器测量了炸药的反应超压。对加速老化前后炸药的试验结果进行了对比,试验结果初步表明加速老化前后的PBX-2炸药在Steven试验中发生反应的反应程度和受力过程并无明显变化。     

Steven试验中不同形状弹头撞击下炸药响应规律研究

采用2 kg小钝头弹丸、针状弹丸和平头弹丸分别对PBX-2炸药进行了Steven试验,试验中采用锰铜压力计和聚偏二氟乙烯(PVDF)压电式压力传感器测试了样品中的压力变化过程,通过高速录像照片分析了点火反应过程; 通过冲击波超压传感器测量了炸药的反应超压,分析了Steven试验中不同形状弹头撞击的影响规律.结果初步表明,Steven试验中由于平面撞击产生的强剪切带作用使得炸药反应更剧烈,平头弹丸撞击时PBX-2炸药反应程度更高.     

慢烤试验中PBX-6炸药件的响应特性（英文）

为了解缓慢加热对炸药件安全性的影响,分别开展了PBX-6粉末炸药样品在压力1 MPa和0.101 MPa、升温速率2℃·min~(-1) 和5℃·min~(-1) 的DSC分析,以及SR50mm PBX-6半球炸药件在55℃、140 d的加速老化试验。设计了Φ100 mm球形炸药件的慢烤试验装置,对球形S-1~#和S-2~#试样进行了升温速率分别为2℃·min~(-1) 和5℃·min~(-1) 的慢烤试验。通过热电偶和温度测试系统记录测量位置的温度变化,结合冲击波超压和试验残余物对比分析试验结果,探讨慢速烤燃行为与热分解特性的关系,综合评估PBX-6炸药件在缓慢加热条件下的安全性。结果表明,升温速率2℃·min~(-1) 时,S-1~#试样的爆燃时间为8373 s,爆响温度为218.5℃,爆燃反应较弱。升温速率5℃·min~(-1) 时,S-2~#试样的爆燃时间为4074 s,爆响温度为224.9℃,冲击波超压为21.8kPa,爆燃程度较大。即升温速率越大,试样的爆响时间越短,爆响温度越高,爆燃程度越大。     

模拟跌落撞击下PBX-2炸药的响应

为了研究带壳体约束条件下炸药的跌落安全性,设计了模拟跌落试验装置.对φ98 mm ×39 mm PBX-2炸药进行了跌落试验,采用polyvinylidene fluoride(PVDF)计测试了样品中的压力变化过程,采用PCB加速度计获得了装置中不同位置的加速度变化过程,通过高速录像照片分析了点火反应过程,通过冲击波...     

常温和75℃条件下PBX-2炸药射弹撞击响应特性

为了研究常温和75℃条件下PBX-2炸药射弹撞击响应特性,采用高温撞击试验装置对PBX-2炸药进行了射弹撞击试验。采用冲击波超压传感器测量了炸药的反应超压,结合回收样品综合分析了常温和75℃下炸药的响应特性。采用有限元程序LS-DYNA计算分析了不同撞击速度对应的常温和75℃PBX-2炸药的受力变化。结果表明,常温下PBX-2炸药撞击点火反应速度阈值为263.5~269.9m·s~(-1);加热至75℃时,PBX-2炸药撞击点火反应速度阈值为316~367m·s~(-1)。相比常温状态,当射弹撞击速度低于800m·s~(-1)时,75℃条件下PBX-2炸药反应程度明显下降,但射弹撞击速度高于800m·s-1时,约1.54GPa的输入压力就能使75℃PBX-2炸药产生剧烈反应。     

PBX炸药药片的摩擦感度响应特性

为研究高聚物粘结炸药(PBX)在摩擦作用下的响应特性,采用药片摩擦感度试验装置分别对PBX-923和PBX-2炸药进行了试验,采用冲击波超压传感器测量了样品的反应超压,根据回收样品分析了两种炸药的响应特性,计算了摩擦作用下PBX发生点火的摩擦功阈值和摩擦功率,分析了药片摩擦感度试验中炸药的点火机制。结果表明,炸药与光滑的钢板摩擦时PBX-923炸药和PBX-2炸药的反应摩擦功分别大于515.9 J和583.2 J,摩擦功率分别大于10.12 k W和11.44 k W,而PBX-923炸药与砂靶摩擦时对应的反应摩擦功阈值为294.7~368.3 J,摩擦功率为7.80~9.75 k W,PBX-2炸药与砂靶摩擦时反应摩擦功阈值为147.3~191.5 J、摩擦功率为3.90~5.07 k W,表明摩擦作用难以整体均匀加热PBX发生点火,炸药与砂靶摩擦的点火主导机制是摩擦引发的剪切作用点火。     

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.     

Method for Measuring Velocity of Warhead Fragments Based on Photoelectric Detection

For measuring velocity and impacting position of single fragment of warhead, a non-contact measuring method is proposed, in which a six-light-screen array, a position indicator, a multi-channel chronograph and a computer are used.The principle of measurement is described. The key device of the system is a light screen array sensor which consists of six light screens allocated with certain geometrical parameters. When the fragment flies through the light screen array, the time of passing through each of the screens is recorded by the multi-channel chronograph. According to the time data and the geometrical parameters of the array, the velocity vector and the location of the fragment can be calculated immediately. The presented method can be used to locate the fragment and to measure the real velocity on its flying direction. It can also be used to measure the velocity of a fragment swarm after the system is engineered further.     

数码电子雷管中影响点火头性能因素分析

阐述了数码电子雷管中,点火药剂细结晶三硝基间苯二酚铅（LTNR）的制备工艺;从点火药剂的种类、加入黏合剂的质量分数、桥丝直径、点火头的电阻值、防潮漆的蘸涂等方面对点火头性能的影响因素进行了探讨;通过震动试验、并联起爆试验、延期精度检测与考核,试验结果表明：一次性合成的细结晶LTNR是制造数码电子雷管点火头较为理想的点火药剂,按技术要求生产的点火头性能指标能够满足行业标准要求。     

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.     

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.