Effects of nano-sized aluminum on detonation characteristics and metal acceleration for RDX-based aluminized explosive

Nano-sized aluminum(Nano-Al)powders hold promise in enhancing the total energy of explosives and the metal acceleration ability at the same time.However,the near-detonation zone effects of reaction between Nano-Al with detonation products remain unclear.In this study,the overall reaction process of 170 nm Al with RDX explosive and its effect on detonation characteristics,detonation reaction zone,and the metal acceleration ability were comprehensively investigated through a variety of experiments such as the detonation velocity test,detonation pressure test,explosive/window interface velocity test and confined plate push test using high-resolution laser interferometry.Lithium fluoride(LiF),which has an inert behavior during the explosion,was used as a control to compare the contribution of the reaction of aluminum.A thermochemical approach that took into account the reactivity of aluminum and ensuing detonation products was adopted to calculate the additional energy release by afterburn.Combining the numerical simulations based on the calculated afterburn energy and experimental results,the param-eters in the detonation equation of state describing the Nano-Al reaction characteristics were calibrated.This study found that when the 170 nm Al content is from 0％to 15％,every 5％increase of aluminum resulted in about a 1.3％decrease in detonation velocity.Manganin pressure gauge measurement showed no significant enhancement in detonation pressure.The detonation reaction time and reaction zone length of RDX/Al/wax/80/15/5 explosive is 64 ns and 0.47 mm,which is respectively 14％and 8％higher than that of RDX/wax/95/5 explosive(57 ns and 0.39 mm).Explosive/window interface velocity curves show that 170 nm Al mainly reacted with the RDX detonation products after the detonation front.For the recording time of about 10 μs throughout the plate push test duration,the maximum plate velocity and plate acceleration time accelerated by RDX/Al/wax/80/15/5 explosive is 12％and 2.9 μs higher than that of RDX/LiF/wax/80/15/5,respectively,indicating that the aluminum reaction energy significantly increased the metal acceleration time and ability of the explosive.Numerical simulations with JWLM explosive equation of state show that when the detonation products expanded to 2 times the initial volume,over 80％of the aluminum had reacted,implying very high reactivity.These results are significant in attaining a clear understanding of the reaction mechanism of Nano-Al in the development of aluminized explosives.     

岩土材料屈服准则的可靠度解析

视岩土材料强度参数为正态分布随机变量,以可靠度理论为基础,推导了Drucker-Prager准则和Mohr-Coulomb准则可靠度判别的解析表达式,并通过Monte-Carlo法和一次可靠度方法验证了其正确性.应用所得到的可靠度解析公式分析了岩土材料强度参数的均值和变异性对屈服准则判别结果的影响.结果表明,强度参数的变异性对Drucker-Prager准则和Mohr-Coulomb准则可靠概率的影响程度不尽相同,在变异系数较大的情况下,它们对可靠概率的影响显著,不可忽略.该研究结果为岩土材料屈服的可靠度判别提供了一条新思路.     

适于坐标支援的航迹滤波算法研究

在网络化作战系统中,外围战需要实时接收来自目标指示雷达或制导雷达的坐标支援信息,其精度是外围战射击目标的保障.通过对某型雷达传统滤波算法的自适应调整,解决了传统方法在目标机动阶段精度差的问题;通过仿真分析,该方法满足精度指标,能够达到实战的要求,具有一定的工程实践价值.     

发射装药非稳态温度场仿真

弹药在长期贮存过程中,极易受环境温度和湿度的作用,使发射装药出现热分解、裂解、结霜等,严重影响弹药装药的贮存可靠性;在射击试验中,发射药温度也会对弹道性能产生极大的影响。由于不允许对弹药进行破坏性开孔,因此借助Ansys的热分析模块,对发射装药非稳态温度场进行仿真研究,获取发射装药在不同环境条件下的温度场及不同节点的温度变化规律,为弹药的贮存、试验提供一定的参考价值。     

Xunzi on the Role of the Military in a Well-Ordered State

Chapter 15 of the Xunzi stands as the most comprehensive account of the early Confucian analysis of warfare. Unlike a range of other early, non-Confucian discussions on warfare, particular strategies and tactics are taken to be of secondary importance. Thus, Xunzi refuses to discuss practical military strategy without framing it within a much broader ethical, social, and political context. On his account, a well-ordered, flourishing state necessarily rests upon a particular set of rituals and social norms in which people can cultivate themselves morally. Such a state has nothing to fear from any enemy, no matter how tactically sophisticated or militarily skilled. To many, such a view seems overly optimistic. However, given that Xunzi is anything but Pollyannaish in other parts of the text and is quite pessimistic about human nature in general, it behooves us to dig a bit more deeply into his ideas about military affairs and examine whether they can be understood in a more plausible light. This article provides a reading of Xunzi’s views on military affairs that is internally consistent and corresponds with Xunzi’s broader ethical and political views, while also showing why someone of Xunzi’s obvious intellectual acumen might hold such a view.     

两栖突击作战系统通过通路生存能力仿真分析

对两栖突击作战系统通过障碍区的行动进行仿真分析,考察通路的数量、通路的宽度、蓝军火力威胁等因素对其生存能力的影响,进而提出提高两栖突击作战系统生存能力的有效措施。     

加权振动烈度在齿轮箱状态监测中的应用研究

针对齿轮箱运行过程中状态监测的性能特征参量及其评价标准的确定问题,研究以齿轮箱振动烈度为性能特征参量,依照国标GB6075—1985来判定齿轮箱运行状态,提出在特征频率处计算振动烈度,即加权振动烈度,以此作为监测量来判定齿轮箱性能状态,并可以对故障进行初步定位。     

土质边坡工程风险分析

扼要地阐述了边坡工程事故引发的原因和边坡工程体系包含的不确定因素,从自然、社会、经济、管理等方面对这些因素进行了归纳,介绍了安全评估的故障树分析法以及由顶事件概率求底事件概率的计算公式.从技术的角度对土质开挖边坡工程体系进行了研究,建立了边坡工程故障树模型以及在此模型下边坡工程风险事件发生概率Pf的计算方法.在求解风险损失的过程中分析了传统专家调查法存在的不足,从而提出改进的专家调查法.通过工程实例,定性和定量地对边坡工程风险进行了分析,利用风险分级体系对风险的大小进行评价,为边坡工程风险管理提供了一定的依据.     

基于Mohr-Coulomb准则深埋球形洞室的弹塑性分析

基于岩体力学中关于深埋圆形洞室的假设和Mohr-Coulomb准则,推导了深埋球形洞室开挖后应力弹性分布、塑性分布和塑性区半径的公式.并用所得到的公式与圆形洞室进行了比较.算例表明,在相同荷载、岩体强度参数和几何尺寸的前提下,球形洞室的受力比圆形洞室合理.     

STAGE软件在战术作战实验室建设中的应用

随着仿真技术的飞速发展 ,作战实验室对提高军队战斗力将发挥越来越重要的作用。 STAGE软件提供了一种良好的作战仿真环境 ,利用它可以构建起功能强大的作战实验室。简要介绍了作战实验室的概念、结构与用途 ,详细分析了STAGE软件的功能和体系结构及其应用开发接口 ,在此基础上 ,探讨了 STAGE软件在构建战术作战实验室仿真应用系统中的应用