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1.
AGHF is a Bridgman Furnace Facility for directional solidification experiments in microgravity environment with very well controlled heater temperatures up to 1400°C. A laboratory model and an engineering model exist, the flight model will be built at the end of 1991. The furnace uses heater elements made of W-Re wire wound on a solid TZM heat diffuser, diffuser temperature control by Pt/PtRh thermocouples to ±0.2 K, and a water cooled cooling zone regulated by a thermostatic valve to ±0.3 K. AGHF experiments use front loaded cartridges, which can use conductive coupling to the cooling zone by a liquid metal ring or radiative cooling. The laboratory model furnace, mounted in a dedicated vacuum chamber with peripherals controlled by a commercial computer, was intensively tested up to 1400°C, as specified for the AGHF by ESA, and at 1500°C in a life test under a technology development programme of ESA. Notable laboratory model results are gradients of 95 K/cm in solid Ni of 18 mm dia, with conductive cooling zone coupling by liquid metal, and 70 K/cm with radiative cooling in ZrO2. EM test are not yet complete, but first tests indicate similar or better results, especially of gradient constancy vs pulling stroke over 140 mm. The first heater model sustained 400 h at 1000°C, 800 h at 1300°C, and 400 h at 1500°C.  相似文献   

2.
为了快速、便捷分析天基侦察系统的对地覆盖性能,开展综合对比分析,设计开发天基侦察卫星星座对地覆盖性能仿真分析系统。仿真系统基于VS2010平台开发,通过软件交互接口调用STK引擎完成计算,使用Matlab编译的库函数完成仿真数据处理及可视化输出。仿真系统采用Redis数据库实现输入参数和仿真结果的存储,并提供与外部程序静态和动态交互功能。仿真系统提供独立仿真和协同仿真两种工作方式,可独立运行分析星座覆盖性能,也可作为其它仿真系统的一部分,在外部命令控制下运行。经应用测试,该系统可以快速、有效完成卫星星座对地面目标的覆盖性能对比分析,为天基侦察系统星座构型设计论证提供支撑。  相似文献   

3.
针对固体推进剂的配方性能预示,使用Oracle设计并构建配方信息数据库,用Delphi开发客户端软件,调用预示及优化模块,实现推进剂性能参数与影响因素的映射。开发出整套软件系统,并将其用于实际生产,效果良好。  相似文献   

4.
This historical paper reviews the technical development and the political impact of two “intelligence affairs” with German rocketry in African countries: 1. the Nasser missiles and space projects in Egypt during the 1960s; 2. the private OTRAG venture in Zaire and Libya during the 1970s.  相似文献   

5.
流量调节器是液氧煤油火箭发动机中关键的自动调节装置,其动态性能直接影响发生器乃至发动机的工作特性.为进一步验证流量调节器工作可靠性,设计并集成了调节器低温动性能试验台测量系统.测量硬件基于PXI系统搭建,软件基于LabVIEW平台进行编程.首先介绍了测量系统的总体方案及工作原理,然后对热电偶测量方法、硬件选型、软件总体架构、软件子模块设计及拖拽式数据显示方法进行了重点阐述,最后简要说明了测量系统的调试方法及结果.测试结果表明,测量系统稳定、可靠,能满足试验要求.  相似文献   

6.
从分析电子战设备性能参数的数据特点入手,总结了设备性能参数库实体关系模式和竖表模式两种概念模型的设计思路、关键技术及其优缺点和适用性。工程应用结果表明,实体关系模式适用于从属仿真系统的数据库子系统;竖表模式适用于独立的情报数据库系统。  相似文献   

7.
Main test processor (MTP) software is the key element of Electrical Ground Support Equipment (EGSE) for spacecraft test and operation used in the Chinese Academy of Space Technology (CAST) for years without innovation. With the increasing demand for a more efficient and agile MTP software, the new MTP software was developed. It adopts layered and plug-in based software architecture, whose core runtime server provides message queue management, share memory management and process management services and forms the framework for a configurable and open architecture system. To investigate the MTP software's performance, the test case of network response time, test sequence management capability and data-processing capability was introduced in detail. Test results show that the MTP software is common and has higher performance than the legacy one.  相似文献   

8.
In this paper, we propose a new suspension for lunar rover called obverse and reverse four-linkage suspension (ORF-L suspension for short). Its two components are designed based on the evolutions of bogie and rocker. Firstly, we analyze the character of bogie and research the approach to improve its performance. Based on that research, an evolved mechanism of bogie is proposed, named obverse four-linkage. It has better capacity than bogie. In addition an evolved mechanism of rocker is also proposed, named reverse four-linkage. The bogie, rocker and their evolved mechanisms can compose four available suspensions including the interested ORF-L suspension. Because ORF-L suspension is composed of two evolved mechanisms, it has the highest performance. In order to check that, the performance comparison between ORF-L suspension and rocker-bogie suspension are carried out based on simulation. Finally, a prototype rover with ORF-L suspension is designed and manufactured. It shows excellent performance as expected.  相似文献   

9.
10.
A recent study made by ESA has reviewed the scientific investigations to be only, or best, performed on the Moon (Return to the Moon, ESA SP-1150, June 1992), and has identified the need for a manned lunar outpost to provide support to field geologists in sampling and in-situ observations of the lunar surface, and to allow the refurbishments of surface stations and rovers. Planning and development for a manned outpost on the Moon requires an in-depth understanding and analysis of the functions this outpost is expected to perform. We therefore analyzed the impact of the proposed scientific investigations on the design of a manned lunar outpost. The specific questions raised in our study were: What are the medical, physiological and psychological risks for a crew to stay and to work on the Moon? What transit and lunar surface infrastructures (habitats and vehicles) are needed to minimize those risks?  相似文献   

11.
A simulation for flight of international crew on space station took place in Moscow from July 1999 to April 2000 (SFINCS) at the State Biomedical Institute of Russia (IBMP) isolation chambers. Objectives of this study were to identify concepts of psychosocial adaptation and of social interactions to develop an explanation of the transcultural group performance. Method: constructivist epistemology with grounded theory research and fourth generation evaluation were used. Data on processes and interactions were gathered during 110 days of confinement as a subject and extended to 240 days as an outside scientist. Results indicate that coping is influenced by usual coping strategies and coping behaviors inside. Several stresses and human factor issues were identified altering well being and performance inside the chambers. Enabling and limiting forces are discussed. A theory on transcultural group performance is proposed. Issues are raised that appear critical to selection, training and group performance.  相似文献   

12.
This paper shows that cortical processing of information quantity can be given in bits, while speed of information processing can be given in bit/sec; therefore the information processing ability can be denoted in algebraical expression. Changes of emotional tension can be objectified by galvanic skin reflex and pulse reaction. This method and device is suitable to measure psychic state of space station personnel and to predict psychic activity.  相似文献   

13.
新型穿透式复合材料薄膜盖的设计、制作与实验   总被引:2,自引:1,他引:2  
周光明  袁卓伟 《宇航学报》2006,27(2):276-280,316
以复合材料层合板为基本材料设计了一种结构新颖的穿透式薄膜盖,在导弹与薄膜盖初始接触区域预制薄弱区,导弹顶破时以四瓣形式开裂,提高了导弹的发射效率.通过强度分析确定了设计方案,然后自行制作了实物,并进行了实验验证,结果表明结构设计合理,理论预测和实验方法准确.本文所建立的方法和研究结果为这类箱盖的设计应用提供了依据.  相似文献   

14.
The Advanced Stellar Compass (ASC) is a second generation star tracker, consisting of a CCD camera and its associated microcomputer. The ASC operates by matching the star images acquired by the camera with its internal star catalogs. An initial attitude acquisition (solving the lost in space problem) is performed, and successively, the attitude of the camera is calculated in celestial coordinates by averaging the position of a large number of star observations for each image. Key parameters of the ASC for the Ørsted satellite and Astrid II satellite versions are: mass as low as 900 g, power consumption as low as 5.5W, relative attitude angle errors less than 1.4 arcseconds in declination, and 13 arcseconds in roll, RMS, as measured at the Mauna Kea, HI observatories of the University of Hawaii in June 1996.  相似文献   

15.
研究了机械球磨法制备的铝锂合金微观结构与水解性能,考察了金属锂含量和其他金属掺杂的影响,并探讨了相关的改善机制及水解机理.结果表明,增加锂含量和其他金属(X:Bi,Sn,Ga和In)掺杂,可明显改善铝合金的水解性能.通过XRD、SEM和水解测试等实验分析,增加锂含量的作用在于:在球磨过程中减小合金粉颗粒尺寸;金属锂水解释放大量的热量和碱性物质LiOH改善铝的水解动力学.其次,掺杂金属X与金属锂形成金属间化合物LiX,LiX与AIX在水中易形成双重腐蚀电池,促进了金属铝的水解动力学.  相似文献   

16.
PRISMA (PRecursore IperSpettrale della Missione Applicativa) hyperspectral instrument is an advanced hyperspectral sensor including a panchromatic camera at medium resolution. The instrument is the focus of the new Earth observation mission that a consortium of Italian companies has started developing under contract of Italian Space Agency. Key features of the instrument are the very high requirement for signal-to-noise and the high quality of data that have to be provided. To meet these demanding figures the optical system has been based on a high transmittance optical system, including a single mirror telescope and two prism spectrometers based on an innovative concept to minimize number of optical elements, while high performance detectors have been chosen for the photon detection. To provide the required data quality for the entire mission lifetime an accurate calibration unit (radiometric and spectral) will be included in the instrument optomechanical assembly. The thermo-mechanical design of the instrument is based on innovative concepts, considering that the use of prism spectrometers implies a tight control of temperature variations to guarantee the stability of all instrument features once in orbit. The presented paper describes the concepts and design principle of the optomechanical assembly of the instrument, at the present status of development.  相似文献   

17.
剖析AIXM的目标、需求与设计   总被引:1,自引:0,他引:1  
自全球空中交通管理(GLOBALATM)推出后,为了营造一个与之相适应的全球航空信息管理(GLOBAL AIM)体系,国际民航组织在第11次航行会议上建议,应尽快制定一个能够充分满足系统运行和数字化信息交换需求的公用航空信息交换模式。然而,由FAA与EUROCONTROL联手策划的航空信息交换模型  相似文献   

18.
浅析产品设计的通用化、系列化、组合化(模块化)   总被引:4,自引:0,他引:4  
概述在武器装备研制中推行"三化"的意义,介绍"三化"的方法、对象以及三者之间的共同点、联系与区别,并对企业开展"三化"工作提出几点建议。  相似文献   

19.
评价了国内固体火箭发动机喉衬中成功应用的第一代高强石墨、第二代高密高强石墨、第三代各向同性石墨的物理、力学、热学等材料基本性能和抗热冲击、耐烧蚀等应用功能,并与国外相应的石墨材料性能与功能进行了分析对比,为建立喉衬用石墨材料数据库奠定了基础。揭示了石墨材料拉伸强度、热导率、弹性模量及热膨胀系数与抗热冲击功能的关联度。指出适当放大配料方的最大颗粒度,提高石墨化温度和适宜控制石墨材料的密度范围,是提高各向同性石墨材料综合性能的重点改进方向。  相似文献   

20.
氧化亚氮双组元发动机热力性能计算分析   总被引:1,自引:0,他引:1  
对绿色推进剂N2O,H2,CH3OH,C2H5OH,CH4,C2H6,C2H4,C2H2,C3H8及C3H6的物性进行了全面比较,并采用吉布斯最小自由能法对9种氧化亚氮双组元推进剂组合的热力性能展开全面计算及分析。N2O/H2组合由于其最低的燃气平均摩尔质量而具有最高的比冲;N2O/C2H2组合由于C2H2很高的标准生成焓其燃烧温度可高达3823 K;碳氢燃料在余氧系数α<0.4富燃工况下燃气中含有固碳颗粒,且摩尔含量随着α的降低而急剧升高,喷管出口处可高达35%~40%;N2O/C3H8和N2O/C3H6组合拥有很好的空间应用物性和较高的热力性能,在压比pc:pe=70 atm:1 atm工况下平衡流比冲分别为2 639 m/s和2 656 m/s,具有很好的应用前景。  相似文献   

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