超音速反舰导弹航向180°大空域机动研究

介绍了超音速反舰导弹实现180°大空域机动的过载控制系统设计,对比分析了在几种情况下实现导弹大空域机动的优缺点.研究表明,在一定的条件下,超音速反舰导弹是能够实现航向180°大空域机动的.     

洛克希德YF—22概貌

1 ATF的研制过程 先进战术战斗机ATF是美国空军F-15的后继机,绰号“大天”。美国空军在1981年11月正式开始研究ATF,首先向各家飞机制造厂商发出招标意向书。 1983年9月,空军与波音、通用动力、格鲁门、洛克希德、麦克唐纳道格拉斯、诺斯罗普和罗克韦尔7家公司签订了关于进行飞机基本形态方案设计的研究合同。1984年末,ATF的性能和机体规模大体上确定了,作战半径约1300千米,不用加力的超音速巡航速度为马赫数1.4～1.5,所需跑道长610米,最大起飞重量     

下一代战斗机设计中的几个飞行力学问题

综述了下一代机设计中的超音速巡航和隐形，敏捷性与过失速机动和空战模拟等几个飞行力学问题，讨论了这些问题提出了背景，每个问题中涉及的飞行力学内容，介绍了国内外在这些方面的进展，着重讨论其中的过失速机动的机理，典型飞机的非线性控制律设计以及建立作为战斗机作战效能评估所用的空战模拟软件，并在其设计中应当考虑的几个主要问题，而由此得以相应的结论。     

冲压推进技术评论

从飞航式导弹的历史发展的观点,论述了不同时期各类动力装置在导弹中的地位和作用.指出随导弹的不断发展,战术技术性能的不断提高,目前导弹正向超音速和高超音速(Ma>2～6)、中高空(H>15～40km)、超低空(H<30～100m)和中远程(L>100km)方向发展,而航空航天技术的发展也从亚音速、超音速开始发展到高超音速.这就是说导弹和航空航天技术已经发展到进入冲压发动机最佳工作领域的新阶段.为了适应未来新一代导弹以及军民用高超音速飞行器的技术要求,就必须发展一种重量轻、体积小、速度快、射程远而机动性能又好的动力装置,而冲压及其组合推进技术则是它的最佳选择.现在冲压推进技术本身的发展已近成熟,而导弹和航空航天的技术发展又为它提供广阔的活动新天地,冲压推进技术活跃于世界舞台的新时代即将到来.     

具有过失速机动能力的不稳定飞机大迎角下俯力矩研究

现代歼击机一般都是纵向不稳定的且有过失速机动能力的飞机。静不稳定飞机作过失速机动的前提是在大迎角时具有足够的、可操纵的下俯力矩。本文结合近年来国外陆续发表的几项判别准则和我国的歼击机先进气动布局研究成果,论述所需下俯力矩大小及在飞机布局上实现的可能性。文中引用的曲线来自具有超音速巡航、高机动能力、隐身、双发、双立尾的三种布局方案的风洞试验结果。三种布局形式即:正常式,鸭式,三翼面布局。     

图—144LL超音速运输机低阶等效系统识别

介绍了依据超音速运输机图－144LL的飞行试验数据进行的低阶等效系统模型识别。飞行试验包括在超音速巡航状态下，纵向和横／航向的机动。采用飞行员扫频和多步机动获取闭环低阶等效系统建模的数据。使用灵活的高精度傅氏变换和频域范围内的方程误差／输出误差（EE／OE）公式估算了模型参数，将结果与参数估算值做比较。其估计方法是采用频谱估算和在伯德图上对频响数据做连续最小二乘拟配，两种方法所取得的结果对于扫频和多步连续机动来说都十分吻合，对多步机动来说，EE／OE方法给出了一个可改进预估能力的较好的模型拟合，给出了图－144LL闭环低阶等效系统识别结果的计算值及列表，包括估算参数。标准差，飞行品质等级的预测值。     

超音速、小高超音速三元薄翼非定常二次理论的准确度及其适用范围

 本文处理了超音速三元薄翼非定常问题,通过PLK法使二次解均匀有效。首先考虑零攻角或初始攻角时,已知基本定常绕流叠加高-量级的非定常小扰动流,把它线性化。本方法从健全的基本方程出发,使用高马赫数近似,将非定常二次方程化简,其形式与定常二次方程类似,因而有可能利用定常二次理论的方法求解。特解是求解的关键。鉴于精确特解的复杂性,本报告采用了一种近似特解。 本方法适于一般超音速和完全高超音速之间的马赫数区域（约3～8）,折合频率可达至1左右。可较精确地估计厚度,初始攻角对非定常气动力,力矩的影响。 目前据我们所知,还没有有关实验数据,只能和一些理论结果进行比较。为此对低频有初始攻角的超音速前缘平板三角翼进行了计算,在马赫数3～8,与D.D.Liu^[6]比较吻合。计算结果表明,三元薄翼二次理论可用到高超音速相似参数Mδ=1.0。     

Chinese Journal of Aeronautics(航空学报英文版)摘要

应用密切锥及密切轴对称流理论设计高速气动外形=HighspeedflowdesegnusingthetheoryofoscultingconesandaxisymmetricH.Sobieczdy(德国宇航研究院),B.Zores,王卓(北京航空航天大学),钱翼稷.1999,12(1)1～8　　在超音速流场的密切锥(OC)设计概念中引进逆特征线法,扩大了人...     

导弹靶弹弹道机动变轨通用控制指令设计

导弹进行一定强度的机动飞行,就能够提高突防能力,因而,在军事训练中需要具有末端机动变轨能力的靶弹.针对靶弹机动变轨弹道的设计问题,提出变轨通用控制指令设计形式,利用此设计可使靶弹位移与过载指令控制信号协调配合,控制靶弹实现跃升机动、蛇行机动、摆式机动和螺旋机动等变轨形式.通过仿真证明,此设计的变轨弹道通用控制指令,可以满足靶弹跃升机动、蛇行机动、摆式机动和螺旋机动等各种变轨形式的弹道设计要求.     

未来空战与推力矢量技术

从隐身性、超音速巡航、超机动、敏捷性和短距起降等影响空战效能的因素入手 ,研究了推力矢量技术对上述影响空战效能因素的作用。结果表明 ,推力矢量技术是未来战斗机必不可少的关键技术之一。     

K. Koyama, S. Kitamoto and M. Itoh (eds.), The Hot Universe, IAU Symposium

This volume contains the proceedings of the NATO Advanced Study Institute on Polar Cap Boundary Phenomena held at Longyearbyen, Svalbard, Norway on June 4–13, 1997, which was the third NATO Workshop on magnetospheric boundary phenomena observable at high latitudes. Svalbard has a uniquely interesting location from observational point of view in that the dayside aurora can be observed there in the noon local time sector during the midwinter. The Norwegian groups working at Svalbard were the organisers of this third workshop as well as of the two earlier ones, but only this third one was held at Svalbard. It was attended by 86 space physicists from all over the world. The book contains 36 papers, of which the majority were presented as invited papers at the workshop, a few were contributed papers and the last paper in the volume gives a summary of the content of the workshop. As emphasized in both the Foreword and the Summary chapter of the book, the research field of the polar cap and its boundaries to other magnetospheric regions at high latitudes is one that has seen a fast development in the last ten years. This is to a great deal due to the research work done at Svalbard in combination with satellite measurements and theory development. The review in these proceedings provide also the non-specialist reader with good summaries of where different research questions stand at present. This revised version was published online in August 2006 with corrections to the Cover Date.     

R. Burkhardt, U. Esser, H. Hefele, I. Heinrich, W. Hoffmann, V. R. Matas, L. D. Schmadel, R. Wielen and G. Zech (eds.), Astronomy and Astrophysics Abstracts, Volumes 69A and 69B, Literature 1998, Part 1, published for Astronomisches Rechen-Institut

The reviewed Volumes of the AAA series record, summarize and index nearly 12 000 papers covering all aspects of astronomy and space sciences, published throughout the world during the first half of the year 1998. The AAA series is the most important source of information on progress in the scientific disciplines. They have become an indispensable source of information for scientists and students involved in the Universe research. This revised version was published online in August 2006 with corrections to the Cover Date.     

Exploratory and Advanced Development in the U. S. Navy

The relationship of Exploratory and Advanced Development to the overall Navy research, development, test, and evaluation (RDT & E) program is indicated in terms of the proportion of funds allocated. Selected projects and areas of work are named or discussed and the proportionate allocation of funds to Navy bureaus is indicated to present representative pictures of Exploratory Development (exemplified by a Bureau of Ships electronics program) and Advanced Development (exemplified by a Bureau of Naval Weapons electronics program).     

Conversations with Rep. Ken Calvert. Interview by Frank Sietzen Jr

Rep. Calvert, chair of the House aeronautics and space subcommittee of the Science Committee, answers questions related to priorities for space in the current congressional session: the Vision for Space Exploration, development of the Crew Exploration Vehicle (CEV) and other heavy-lift launch vehicles, entrepreneurial alliances in the space transportation industry, the U.S. aerospace industry, space tourism, entrepreneurs and NASA, U.S. aeronautics research, a service mission to the Hubble Space Telescope, and priority military space programs.     

R. Buccheri, J. van Paradijs, M. A. Alpar, The Many of Neutron Stars

We see neutron stars principally by their radio and X-ray emission. Their appearance in these different bands depends on whether the emission comes from the surface or its magnetosphere. New phenomena continue to be found from neutron stars, which makes it an exciting and topical research area. This volume is a collection of the papers from a NATO Advanced Study Institute held in Italy in October 1996. Many, and for me the most interesting ones, are substantial reviews on topics such as Pulsar magnetic fields and glitches (M. Ruderman), Radio pulsar population properties (D. Lorimer), Gamma-ray emission from CGRO pulsars (G. Kanbach), Neutron stars and black holes in X-ray binaries (J. van Paradijs), Kilohertz quasi-periodic oscillations in low-mass X-ray binaries (M. van der Klis), Thermonuclear burning on rapidly accreting neutron stars (L. Bildsten), On the X-ray emission properties of rotation powered pulsars (W. Becker and J. Truemper). It will serve as a useful reference and source book for students in high energy astrophysics and related fields. The high price may deter its purchase by individuals, but it will be a good volume for a library needing recent coverage on neutron stars. It does not of course include the most recent developments on anomalous X-ray pulsars or magnetars. This revised version was published online in August 2006 with corrections to the Cover Date.     

加热空气流中燃油液雾特性

近期液雾火焰结构的研究表明,在很多情况下在液雾火焰中燃油液滴并不是以单滴形式烧掉,蒸发液雾形成蒸汽空气雾在稠液雾边界上以扩散火焰方式燃烧掉。这个结果强调了在热环境中液雾蒸发的重要性。基于对单滴蒸发的研究金与Lefebvve导出液雾蒸发模型,在跨流喷射的液雾问题中,已经成功地运用了这个液雾分析模型。这个模型得出     

U. S. Navy in Space: Past, Present, and Future

The announcement last summer of the establishment of the U. S. Navy Space Command, and its subsequent activation at Dahlgren, Va., in October 1983, may have come as a surprise to some. This, however, was the latest of a series of actions taken by the Department of the Navy over the last several years to consolidate the Navy's space efforts. In fact, since the beginning of the Space Age, the Navy has been interested in space and involved in space-related activities. Its contributions in space science and technology have been significant. Driven by a realization that space assets are exceptionally well matched to its global mission, the Navy has become a major user of space. Primary areas of current activity include command, control, and communication and navigation and collection of environmental information. The Navy's operational use of space systems, the nature of the evolving Soviet threat (both air and space) directed in a large measure at U. S. naval targets, and the recent advances made in space technology, all argue for an increased level of Navy involvement in future Department of Defense space activities to secure Navy interests. As viewed by Navy decision-makers, this increased level of involvement will be selective in nature, emphasizing space research and development and operations that are considered vital to Navy interests.     

基于.NET和XML的动态通用查询模块的设计与实现

传统查询模块由于代码固定,不能根据用户需求自由组合查询条件,缺乏健壮性等缺点,已经不能满足信息系统对查询项目不确定性的要求.在研究各类信息系统查询特点的基础上,提出一种新的动态通用查询模块应该具备的功能,查询关键字动态的由数据库确定,查询条件由用户自由组合,采用ASP.NET和C#作为主要开发工具,利用XML文件跨平台交换的特点进行查询参数传递,实现了该模块.最后对系统的异常处理进行了阐述.     

Motor drive technologies for the power-by-wire (PBW) program:options, trends and tradeoffs. I. Motors and controllers

The Power-By-Wire (PEW) program involves the replacement of hydraulic and pneumatic systems currently used in aircraft with an all-electric secondary power system. One of the largest loads of the all-electric secondary power system will be the motor loads which include pumps, compressors and Electrical Actuators (EAs). Issues of improved reliability, reduced maintenance and efficiency, among other advantages, are the motivation for replacing the existing aircraft actuators with electrical actuators. The EA system contains the motor, the power electronic converters, the actuator and the control system, including the sensors. This paper and a companion paper give a comparative literature review in motor drive technologies, with a focus on the trends and tradeoffs involved in the selection of a particular motor drive technology. The reported research comprises the induction motor (IM), the brushless dc motor (BLDCM) and the switched reluctance motor (SRM) drive technologies. Each of the three drives has the potential for application in the PEW program. Many issues remain to be investigated and compared between the three motor drives, using actual mechanical loads expected in the PBW program     

基于接触有限元的齿轮副扭转共振分析

以典型斜齿轮副为对象,基于接触有限元法,先模拟其准静态啮合过程并求解啮合刚度,并与国家标准偏差值进行了对比,证明了分析方法的正确性.再模拟其动态啮合过程,通过对啮合力响应进行频谱分析识别出扭转振动的固有频率,并与绘制频响曲线的识别结果一致.在此基础上,数值模拟了该齿轮副扭转共振的发生、发展和稳定过程,定量分析了共振状态下的典型动力学参数响应.结果表明:脱离啮合现象的发生使齿轮副的啮合冲击更为显著,共振状态下的最大应力值相比啮合频率为3000Hz时增大了20%.