军用油库油罐火灾消防虚拟现实仿真模型研究

军用油库火灾消防模拟训练系统可用于提高部队官兵的消防水平和指挥决策能力,真实感火灾及消防过程的仿真是模拟训练中重要的组成部分。为克服火灾模拟器对硬件系统要求高、可交互性低的缺点,提出并研究了油罐火灾工程模型和火灾消防工程模型。该模型建立了火焰形状、消防力量布置等与三维场景密切相关的数学模型;模型简单可靠,便于在消防三维场景中快速实现。最后通过实例在虚拟场景中进行了模型的仿真。     

长期贮存的固体发动机药柱脱粘界面裂纹分析

为了分析长期贮存的固体导弹发动机药柱脱粘层界面裂纹在燃气内压和轴向过载联合作用下的扩展情况,建立了发动机药柱在包覆层与推进剂之间脱粘的三维有限元计算模型,并于脱粘界面的裂纹尖端设置三维奇异裂纹元,模拟脱粘界面裂纹扩展。在包覆层与推进剂之间设置不同深度脱粘,计算了在燃气内压和轴向过载联合作用下不同贮存期、不同深度的界面裂纹尖端的应力强度因子,得到了界面裂纹应力强度因子随贮存时间、脱粘深度的变化规律,对长期贮存的固体发动机脱粘界面裂纹的扩展进行了分析。     

高压共轨燃油喷射系统结构参数影响的仿真研究

建立了高压共轨燃油喷射系统的模块化数学模型,进行了仿真分析,讨论了主要部件如高压油泵、高压油轨及喷油器的重要结构参数对系统特性的影响,确定了保证系统稳定性的结构参数选取原则.     

RUSSIAN NAVAL NUCLEAR FUEL AND REACTORS

Russian naval nuclear fuel and reactors pose both proliferation and environmental threats, ranging from the possible theft of highly enriched uranium fuel to the radioactive contamination of the environment, whether due to accident, neglect, or sabotage. Current conditions at Russian naval bases, together with a history of accidents and incidents involving Russia's nuclear fleet, make a convincing case for the large-scale assistance that the G8 is now providing to improve the safety and security of Russian naval reactors and fuel. However, virtually no data has been released to allow accurate, reliable, and independent analysis of reactor and fuel properties, risking misguided international efforts to assist in the areas of nuclear cleanup, nonproliferation, and security. This article identifies and assesses relevant properties and developments related to reactor and fuel design, provides a comprehensive presentation of Russian nuclear naval technologies, and examines technological trends in the context of proliferation and environmental security.     

THE NUCLEAR THRESHOLD STATES

“Nuclear threshold states”—those that have chosen nuclear restraint despite having significant nuclear capabilities—seem like the perfect partners for the reinvigorated drive toward global nuclear disarmament. Having chosen nuclear restraint, threshold states may embrace disarmament as a way to guarantee the viability of their choice (which may be impossible in a proliferating world). Supporting disarmament efforts affirms their restraint, both self-congratulating and self-fulfilling. Additionally, the commitment to their non-nuclear status springs at least in part from a moral stance against nuclear weapons that lends itself to energetic support of global disarmament. However, threshold states also offer significant challenges to the movement for nuclear weapons elimination, in particular in relation to acquisition of enrichment and reprocessing facilities. This article analyzes both the challenges and opportunities posed by threshold states by examining the cases of Brazil and Japan.     

CONTRIBUTORS

Russia holds the largest stocks of civilian highly enriched uranium (HEU) of any country, operating more than fifty research reactors, pulsed reactors, and critical assemblies using HEU, as well as nine HEU-fueled icebreakers. Russia's participation in international efforts to phase out civilian HEU is crucial if international HEU minimization efforts are to succeed. Individual Russian institutes and organizations participate in international programs to replace HEU with low-enriched uranium in Soviet-supplied research reactors, develop alternative fuels, and repatriate fresh and spent HEU fuel from third countries. However, an overarching national policy on HEU phase-out has yet to be adopted. There are many obstacles to obtaining such a commitment from Moscow. At the same time, the ongoing reform of the Russian nuclear industry and plans for expansion of domestic nuclear power generation and for increased nuclear exports create opportunities for securing such a commitment.     

一种反压自适应恒流喷嘴工作原理及实验研究

应水反应金属燃料发动机启动过程对水流量的苛刻要求,提出一种新型反压自适应恒流喷嘴。理论分析此喷嘴的流量自适应保持原理,通过流量特性实验验证此喷嘴能够自动调节流阻,实现流量恒定。     

储存喷气燃料中特征真菌的鉴定与生长特性

使用沙保氏平板培养基对储存喷气燃料进行真菌培养,并在沙保氏液体培养基中纯化特征真菌,观察特征真菌菌落及孢子形态,进行形态学初步鉴定。对特征真菌进行18S rDNA测序,将得到的DNA序列在美国国立生物技术信息中心网站上进行比对,最终鉴定储存喷气燃料中的特征真菌为芽枝霉属Amorphotheca resinae真菌。建立起燃料-水-菌落体系,在不同水质量分数、氧气体积分数和温度条件,研究Amorphotheca resinae真菌在燃料中的生长特性,并用颗粒计数器检测不同代谢速度下燃料颗粒污染度的变化。结果表明,较低的水质量分数、氧气体积分数和温度均能抑制Amorphotheca resinae真菌生长,从而抑制由真菌代谢引起的喷气燃料颗粒污染度变化,提高燃料洁净度。     

军用飞机燃油消耗多元线性回归模型

为了解决军用飞机非标准动作燃油消耗建模问题,利用实际飞参数据,采用多元线性回归方法进行建模分析。建立了燃油消耗量与飞行时间、油箱平均油量、平均高度、平均速度、T1温度、T4温度、N2转速、高度变化量、飞机外挂的多元线性回归模型,并对回归模型进行统计性检验和验证。结论显示:模型拟合度较好,符合军用飞机飞行耗油规律,对军用飞机非标准动作燃油消耗规律研究具有重要意义。     

近空间飞行器固体火箭助推器/助推弹道总体设计优化

研究一种近空间飞行器的固体火箭助推器/助推弹道总体优化问题.在选定喷管构型、推进剂、壳体材料、绝热层材料及药柱结构的前提下,建立包含热力学分析与计算、质量分析与计算、气动力分析与计算和弹道设计与计算的系统分析模型,采用一种基于可行性规则与结合模拟退火的混合粒子群优化算法求解最优解.优化结果表明建立的系统分析模型和采用的...