导弹姿控舱体在复杂载荷作用下的强度分析

姿控舱体是动能拦截弹的关键部件.使用Patran和Nastran有限元软件对姿控舱体进行了在弯矩、轴向力、剪切力和脉冲发动机推力等组合载荷作用下的强度分析.得到并分析了不同组合载荷作用下的姿控舱体最大应力的计算结果.计算结果表明:脉冲发动机的组合工作方式是影响姿控舱体强度的最主要影响因素;安装了压紧盖和脉冲发动机的姿控舱体能够在最大的临界组合载荷下安全工作.     

基于ANSYS的脉冲发动机复合壳体优化设计研究

采用ANSYS软件对脉冲发动机复合壳体进行了优化设计研究。用六节点三角形单元对复合壳体模型离散化;在临界压力载荷作用下．分别对两种材料层进行最大应力约束,以减少质量为目标,对复合壳体的壁厚尺寸和过渡圆半径尺寸等设计变量进行了优化。利用表单工具,提出了两种材料复合结构整体一次性优化设计方法。计算结果表明,本优化设计方法可以减轻脉冲发动机复合壳体的总质量。     

基于正交试验的A6063内高压成形加载路径优化研究

为获取航空部件T形管的更高成形质量,对铝合金A6063内高压成形加载路径进行优化研究。以壁厚均匀一致性和最小壁厚为目标函数,内高压、轴向进给、平衡冲头位移为设计变量,设计正交试验。运用Dynaform和LS-DYNA进行数值仿真分析,实验验证该分析的有效性和准确性。结果显示,最佳加载路径与初始路径相比,壁厚均匀一致性提高39.73%,最小壁厚增加192%。     

一种偏置集中力火箭舱体结构优化设计研究

为解决大型运载火箭助推器舱体结构承受偏置集中力问题,开展舱体结构优化设计研究.首先围绕舱段结构多工况、多约束的设计需求,采用多目标折衷规划实现舱体结构整体传力路径拓扑优化,根据拓扑优化结果设计一种"梁式"舱体结构,对舱体结构开展强度仿真分析,计算结果表明,"梁式"舱体结构可以提高整体承载能力14.2％,最后通过地面静力试验验证了舱体结构优化设计的正确性.     

姿控发动机管路支架一体化设计

姿控支架采用管路与结构承力件一体化的设计理念,取消了姿控系统多个姿控发动机管路及其支架,不仅减轻了姿控系统重量,同时也保证了姿控发动机的安装精度.在综合姿控发动机舱内布局、空间尺寸及位置等因素基础上,提出不同结构和不同材料一体化设计的姿控支架方案,并对其在结构强度、刚度、流阻及工艺性方面进行了对比.结果表明,两种不同材料、结构的姿控支架方案皆能满足动力系统使用要求,但钛合金结构方案在重量、系统流阻匹配性方面更具优势.     

防空导弹直接力和气动力复合控制方法

直接力和气动力复合控制是防空导弹对付高速机动目标、兼有反导能力以及发展为动能拦截弹的最现实有效的技术途径。文中对复合控制方法进行了综述,介绍了轨控方式和姿控方式两种典型的复合控制方法,分析了复合控制方法的优越性,并针对姿控式复合控制方法总结分析了其中主要关键技术及当今两种主流的复合控制系统设计方法,最后从工程应用的角度提出复合控制研究中需进一步解决的关键技术问题。     

大展弦比复合材料机翼结构优化设计剪裁

结构优化设计剪裁是减轻结构质量、提高设计品质和产品竞争力的重要手段。以某无人机复合材料机翼为例,采用复合材料结构优化设计系统COMPASS进行满应力设计,给出满足结构静强度约束条件(应力、应变)的结构件总体尺寸分布;在初步设计尺寸基础上,进行以结构质量最小为目标,以复合材料铺层厚度、铺层角度为设计变量的数学规划法优化设计,最终确定满足翼尖变形、自振频率、颤振速度、操纵效率等约束条件的结构件尺寸分布。结果表明,通过复合材料结构优化设计剪裁实现了对大展弦比复合材料机翼结构的静力、动力和气动弹性综合优化设计,有效缩短研制周期,提高了结构效率。     

某特种车驾驶室轻量化设计

在保证特种车驾驶室整体结构力学特性的前提下,省略了一些非承载件,利用有限元软件Hypermesh建立了驾驶室的有限元模型.按照驾驶室实际负荷及弯曲、扭转工况下的边界条件进行加载,利用OptiStrut在弯曲和扭转2种典型工况下对特种车驾驶室进行强度分析,并采用有限元法结合可行方向法对特种车驾驶室进行了轻量化设计.该优化模型以驾驶室的总重量最小为优化目标,以板壳厚度为优化设计变量,以驾驶室结构件的强度值作为约束条件进行优化.最终得到的驾驶室结构在满足强度的前提下,与原结构相比质量减轻约36%,取得了较好的轻量化效果.     

基于iSIGHT卷弧尾翼结构优化设计研究

为使火箭弹卷弧尾翼在特定气动载荷下的结构质量最小,对其进行结构优化设计.在优化中以结构质量最小为目标,以包括尾翼弦长、厚度、前缘后掠角等几何参数为设计变量,强度和变形量为约束,通过集成iSIGHT和MSC.PATRAN/NASTRAN对卷弧尾翼结构进行优化设计,取得了较好的结果,减重效果明显.随后对优化结果进行分析,得到了对优化目标和约束影响较大的设计变量分别是:卷弧的圆心角和翼片厚度.     

射流阀门开/闭过程无网格法数值模拟

为研究姿轨控发动机射流换向阀门开/闭过程的复杂流场,采用耦合两方程湍流模型的最小二乘无网格方法进行数值模拟,清晰捕捉到了合理的流场结构与流动特征,成功模拟出附壁流动、主流的切换等复杂的非定常流动状态,给出了主流切换时间,能够客观地反应射流阀的基本切换过程。数值模拟结果为姿轨控发动机射流阀门的设计提供了参考,耦合两方程湍流模型的最小二乘无网格方法在求解射流阀切换过程这一实际工程问题时具有良好的适应性。     

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.