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1.
飞行器服役完整性(对于军用飞行器也称为作战完整性)更综合地表征了飞行器在服役(作战)使用过程中的质量特性。本文首先介绍了飞行器服役(作战)完整性概念的提出过程,讨论了飞行器服役(作战)完整性的基本内涵和基本特性,阐明了飞行器服役(作战)完整性是飞行器服役(作战)适用性与飞行器服役(作战)效能发挥的基础。然后介绍了飞行器服役(作战)完整性的三种表征参数:飞行器固有完好率、飞行器固有健康度、飞行器服役(作战)完整度,并梳理了飞行器服役(作战)完整性优化设计的基本方法。最后提出了飞行器服役(作战)完整性的控制原理,指出了飞行器服役(作战)完整性发展的基础、研究方法和目前我国航空航天领域急需研究和发展的方向。  相似文献   

2.
空间激光通信现状、发展趋势及关键技术分析   总被引:4,自引:0,他引:4  
针对目前空间激光通信的背景需求,介绍了国内外星、空、地、海等平台间的空间激光通信研究与试验现状。通过对空间激光通信现状的分析,并结合科研实践,归纳出空间激光通信的高速率、网络化、多用途、一体化、多谱段5个未来发展趋势。在此基础上,从空间激光通信系统的光学结构、通信收发以及环境影响等方面,着重分析了高质量光学系统设计、高精度捕获对准跟踪、大气信道影响补偿、高速率高功率发射、高灵敏度低误码探测、一对多通信网络、平台振动与姿态补偿、器件部件空间适应性8项关键技术,并提出相关技术的解决方法和途径,进而给出须进一步深入研究的方向,展示了空间激光通信良好的应用前景。  相似文献   

3.
给出了一种机动多目标雷达视频信号模拟器的软硬件设计方案,它可实时输出所需的多个动目标雷达视频信号,雷达信号的类型、目标的数量、目标的回波特性、目标的运动特性、杂波的类型及参数等均可方便地进行设置。该模拟器可满足各种雷达信号处理算法(如杂波抑制、恒虚警检测、动目标跟踪、多基地数据融合等)的测试与效果分析,以及对雷达信号处理机等进行性能调试与测试的需要。  相似文献   

4.
It is an inevitable trend of sustainable manufacturing to replace flood and dry machining with minimum quantity lubrication(MQL) technology. Nevertheless, for aeronautical difficult-tomachine materials, MQL couldn’t meet the high demand of cooling and lubrication due to high heat generation during machining. Nano-biolubricants, especially non-toxic carbon group nano-enhancers(CGNs) are used, can solve this technical bottleneck. However, the machining mechanisms under lubrication of CGNs are uncl...  相似文献   

5.
热塑弹性体铝合金化学铣切保护涂料的研制   总被引:1,自引:0,他引:1  
采用热塑性弹性体为基体材料制备不同配方的铝合金化学铣切保护涂料.实验包括涂料中酚醛树脂的合成,涂料的制备.所做涂料的性能考核包括外观、粘度、固体含量、抗张性、断裂伸长率、浸蚀比、致密性、剥离强度等.最后与美国同类产品性能对比.研究表明,自制的铝合金化学铣切保护涂料的涂膜透明均匀、剥离强度大小适中、耐强碱,满足化学铣切工艺要求,也基本上与美国同类产品性能相当.  相似文献   

6.
在全系统、全寿命管理的思想基础上,对航空制造巨商———空客公司的用户支援的组织结构与人力分布进行了剖析;从培训服务、技术出版物、技术支援、维修工程、航材支援、供应商控制等6个方面,对用户支援方法进行了详细研究;结合中国国情,从扩充组织结构、确保航材备件、规范手册编制、加大培训力度、建立快速机制等方面,进行了发展途径的探讨。  相似文献   

7.
航空发动机双转子系统不对中研究进展   总被引:1,自引:0,他引:1  
张宏献  李学军  蒋玲莉  杨大炼  陈雨蒙 《航空学报》2019,40(6):22717-022717
转子不对中是旋转机械最常见的故障之一。不对中常引起整机振动加剧、轴承磨损、转静子碰摩等故障,严重时将造成灾难性事故。航空发动机转子系统由于结构复杂、工作温差大、多支点弹性支承,更容易造成滚动轴承支承不对中、联轴器不对中、动态不对中等不对中故障。虽然航空发动机不对中问题严重,但这方面的研究却相对缺乏。本文针对航空发动机转子系统的结构特点,首先论述了滚动轴承不对中、联轴器不对中、航空发动机转子不对中3种不对中故障的研究现状;其次,讨论了不对中转子系统非线性动力学特性及不对中故障定量分析方面的研究成果。最后,对航空发动机双转子系统不对中研究的发展趋势进行了展望。  相似文献   

8.
针对航天测控系统建设目前所面临的角色定位转换、功能体制转型,以及任务要求不断提高、测控技术快速发展等新形势和新要求,分析了航天测控系统的建设管理和功能体制现状,提出了坚持一体规划、推动系统建设,坚持与时俱进、提升建设标准,坚持信息主导、突出建设重点的系统建设转型思路.并在此建设思路的基础上,提出了装备研制向型谱化、标准化转型,维修保障向全寿命、体制化转型,软件开发向产品化、装备化转型,以及推进一体化网络化、强化综合能力、重视安全性可靠性等建设举措.  相似文献   

9.
中国脉冲爆震发动机技术研究现状及分析   总被引:2,自引:0,他引:2       下载免费PDF全文
脉冲爆震发动机是利用脉冲式爆震波产生推力的新概念推进系统,具有热循环效率高、结构简单、成本低和质量轻等诸多优点,因而与其相关的科学与技术问题引起世界性关注.讨论了脉冲爆震发动机的工作模式和应用前景,简要回顾了近年来中国脉冲爆震发动机的研究工作,包括燃料的喷射与混合、起爆、爆燃向爆震转变机理、进气道、增推方法、性能分析与数值模拟、多管PDE、组合循环与混合循环、结构强度/换热/噪声分析等.总结了研究中所取得的理论、试验和数值研究成果,对未来脉冲爆震发动机的技术路线和发展方向进行了展望.  相似文献   

10.
For achieving high-speed requirement of underwater vehicle,a conceptual engine,which utilizes the hydroreactive characteristic of several metals under supercavitation environment,has been put forward. Especially,in order to obtain specific impulse as great as possible,a dual water injection system is taken into account. Then thermodynamic cycle model,which lead the improvement of power plant and energy system,is introduced in detail,and thermal efficiency is also analyzed. Furthermore,for investigating the performance of this kind of engine system,detailed thermodynamic calculation and analysis are achieved. Especially,regarding hydroreactive metal fuel Mg/AP/HTPB as our target fuel-rich propellant,considering its obvious deficient oxygen property and the energy property of magnesium/water reaction,theoretical calculation method is established by integrating chemical non-equilibrium with chemical equilibrium. Accordingly,low limit of primary water/fuel ratio is determined. In addition,the qualitative and quantitative relationship of performance parameters,such as theoretical specific impulse,nozzle exit temperature,characteristic velocity,etc.,versus water/fuel ratio is investigated respectively.   相似文献   

11.
《中国航空学报》2023,36(7):282-315
The shape of a spacecraft is transitioning from monolithic, manual, and static to modular, autonomous, and dynamic. Modular Reconfigurable Spacecrafts (MRSs) offer better solutions than traditional monolithic spacecrafts in several aspects, and may become the next generation of spacecraft systems with efficient design, fast deployment, flexible application, and convenient management. This paper reviews the development and technology of MRS from three aspects: Modularity, reconfigurability, and autonomy. Despite the progress of research on MRS, there is still a lack of unified standards and little understanding of related concepts. Based on the understanding of basic concepts, the studies conducted on MRS are reviewed to identify technical requirements and solutions. Aiming at the future development trend of MRS, a novel modular self-reconfigurable spacecraft, referred to as MagicSat, is proposed. Furthermore, the MagicSat system composition, advantages, and application prospects are studied. The enabling technologies and major challenges of MRS are further analyzed in terms of modularization, integrated management, and self-reconfiguration technologies. Finally, the future development trend of MRS technology is predicted, and corresponding suggestions are provided.  相似文献   

12.
以具有良好整体性能的织物作为增强体的纺织复合材料克服了传统复合材料层间剪切强度低、抗分层能力差、开裂敏感等缺点,且具有优异的近净成形能力,易于成型。这些优点使得这种复合材料被越来越广泛地应用于航空航天、船舶、汽车、医疗器械等领域。纺织预制体的可变形性对其渗透率及最终复合材料构件的力学性能有着重要的影响。简要介绍了二维和三维织物的结构特点;阐述了织物的拉伸、横向压缩、面内剪切和弯曲变形机理;基于数值模拟和试验方法,综述了国内外预制体变形研究的进展;最后,展望了预制体变形数值模拟的发展方向。  相似文献   

13.
飞机的电动力系统技术概述   总被引:3,自引:1,他引:3  
电动力系统是一种使用电能的新型飞机推进系统,具有环境友好、高效节能等优点,有望推动飞机实现革命性发展。本文介绍太阳电池、锂离子电池、燃料电池、电机等关键部件/子系统技术的现状、关键技术,并给出统计数据;重点分析了电动力系统的设计技术,包括蓄电池(锂电池)、太阳电池和燃料电池三种纯电动力系统以及基于活塞动力和基于电动力两...  相似文献   

14.
Observations from the ground and four fly-by spacecraft have provided initial reconnaissance of Jupiter's atmosphere. The Pioneer and Voyager data have raised new questions and underlined old ones about the basic state of the atmosphere and the processes determining the atmosphere's behavior. This paper discusses the main atmospheric science objectives which will be addressed by the Galileo (Orbiter and Probe) mission, organizing the discussion according to the required measurements of chemical composition, thermal structure, clouds, radiation budget, dynamics, upper atmosphere, and satellite atmospheres. Progress on the key questions will contribute not only to our knowledge of Jupiter's atmosphere but to a general understanding of atmospheric processes which will be valuable for helping us to understand the atmosphere and climate of the Earth.Realization of the atmospheric science objectives of the Galileo mission depends upon: (a) coordinated measurements from the entry probe and the orbiter; (b) global observations; and (c) observations over the range of time-scales needed to characterize the basic dynamical processes.The Atmospheres Working Group also includes: M. D. Allison, M. J. S. Belton, R. W. Boese, R. W. Carlson, C. R. Chapman, T. Encrenaz, V. R. Eshleman, P. J. Gierasch, C. W. Hord, H. T. Howard, L. J. Lanzerotti, H. B. Niemann, G. S. Orton, T. Owen, C. B. Pilcher, J. B. Pollack, B. Ragent, W. B. Rossow, A. Seiff, A. I. Stewart, P. H. Stone, F. W. Taylor, G. L. Tyler, U. von Zahn, and R. A. West.  相似文献   

15.
运用生态学中物种竞争的原理研究企业之间的竞争问题,分析了企业竞争与共存的生态机制,包括企业竞争的生态特点,如同源性、非对称性、密度效应、双重作用;企业共存的生态机制,如活命——饱餐原理、非专一性、生命周期差异、环境变化、生态位分离等;最后,通过对企业竞争与共存的生态学模型的分析,认为如果两类竞争企业的行业内竞争比行业间竞争激烈.就可能出现两类企业的稳定共存;否则,如果行业间竞争比行业内竞争激烈,就不可能有稳定的共存,结果将是一方胜,另一方被淘汰,胜者的特征是行业间竞争强度大于行业内竞争强度。  相似文献   

16.
Preliminary results of the ETS-II millimeter and centimeter wavelength propagation experiments are presented based on data collected over one year. Rain attenuation is discussed primarily from the statistical point of view. At 34.5 GHz attenuation in excess of 5, 10, and 19.5 dB were observed 1, 0.3, and 0.1 percent of the test time (5500 hr), respectively. At 11.5 GHz attenuation in excess of 2.5, 4.3, 6.3, 10, and 15.5 dB were observed 0.1, 0.03, 0.01, 0.003, and 0.001 percent of the test time, respectively. Duration time of attenuation is also examined for the benefit of a link design. The longest duration of attenuation of the 34.5-GHz wave exceeding 5 dB was about 150 min. At 11.5 GHz, the longest duration of attenuation in excess of 3 dB, was 60 min and that in excess of 6 dB was 10 min. Rain attenuation is discussed also with relation to the radar and the rain gauge data. Depolarization data of 34.5-GHz and 11.5-GHz waves are orocessed statistically, and it is shown that cross-polarization discriminations in excess of 21.5 dB and 29 dB are observed 0.1 percent of the test time at 34.5 GHz and 11.5 GHz, respectively.  相似文献   

17.
New frontiers in soil science are currently found in the investigation of soils in harsh, terrestrial and simulated extraterrestrial environments, the development of new methods and probes for soil characterization, and the eventual investigation, characterization, and development of extraterrestrial soil. Current aspects of space science involving soil studies are presented, including a more detailed soil study program involving the microflora of desert soil ecosystems. Basic precepts are given for preparation, investigation, and use of extraterrestrial soil.Contribution from the Bioscience Group of the Chemistry Section, Space Science Division, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California. Presented as an invitational paper before the Synapsis Club, University of California, Riverside, California, December 3, 1962.  相似文献   

18.
The concept of system of systems (SoS) and the challenges ahead to extend systems engineering (SE) to system of systems is introduced. The birth of a new engineering field may be on the horizon - system of systems engineering (SoSE). A SoS is a collection of individual, possibly heterogeneous, but functional systems integrated together to enhance the overall robustness, lower the cost of operation, and increase reliability of the overall complex (SoS) system. Having said that, the field has a large vacuum from basic definition, to theory, to management and implementation. Many key issues like architecture, modeling, simulation, identification, emergence, standards, net-centricity, control, etc., are all begging for attention. In this review, we go through all these issues briefly and bring the challenges to the attention of interested readers. We will also indicate the existence of an introduction consortium, of interested groups who are getting together to help realize these problems and try to find solutions.  相似文献   

19.
We consider the main aspects of a rather delicate discipline, space-borne coronagraphy, which is essentially performed with white-light, externally-occulted coronagraphs. Methods of observation and recent results are presented in a scientific section; a short account of historical rocket-borne and balloon-borne experiments is also given. The review concentrates on both the NRL-type coronagraphs and the HAO-type coronagraphs, stressing the essential features and merits of numerous experiments which were flown. A small section is devoted to other designs. A large number of figures, including many drawings, are used to illustrate the growing complexity of experiments.Dedicated to: B. Lyot, who built the first ground-based coronagraph; G. Newkirk, who built the first flying coronagraph; G. Nikolsky, who built the largest, each of whom prematurely passed away.On leave from Paris Institut d'Astrophysique CNRS, 98 Bis Bd Arago, F-75014, Paris, France.  相似文献   

20.
民用飞机重心包线研究   总被引:1,自引:1,他引:0       下载免费PDF全文
民用飞机重心包线是保证飞机使用安全的重要防线,是飞机飞行使用中不可逾越的一道屏障。重心包线设计的好坏不仅影响飞机的飞行性能,更直接影响飞机使用的经济性和安全性,其确定是总体、气动、操稳、性能、强度、重量等多专业分析、权衡的结果。从重心对性能的影响,重心限制边界的分析及如何设计好重心包线三个方面进行了较系统的分析研究,为...  相似文献   

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