直接测量法确定受试产品温度稳定时间的研究

文章阐述了温度试验中受试产品温度稳定的重要性,介绍了国内外典型环境试验标准中温度稳定的定义和确定方法;自行建立了用直接测量法确定受试产品温度稳定时间的测试方案、测试设备,进行了有关测试,并与用重量法估计的结果进行了比较分析,同时指明影响受试产品温度稳定的各种因素;最后总结出应用直接测量法确定受试产品温度稳定时间的必要性、优越性、适用条件和注意事项。     

Chang'E-1 Lunar Mission:An Overview and Primary Science Results

Chang'E-1 is the first lunar mission in China, which was successfully launched on Oct. 24th, 2007. It was guided to crash on the Moon on March 1, 2009, at 52.36oE, 1.50oS, in the north of Mare Fecunditatis. The total mission lasted 495 days, exceeding the designed life-span about four months. 1.37 Terabytes raw data was received from Chang'E-1. It was then processed into 4 Terabytes science data at different levels. A series of science results have been achieved by analyzing and applicating these data, especially "global image of the Moon of China's first lunar exploration mission'. Four scientific goals of Chang'E-1 have been achieved. It provides abundant materials for the research of lunar sciences and cosmochemistry. Meanwhile these results will serve for China's future lunar missions.      

航空军工产品实验室环境鉴定试验工作情况分析（1）

文章分为两部分。此为第一部分,主要阐述了军工产品定型试验分类和目的,特别是航空军工产品地面鉴定试验的基本内容;着重分析了实验室环境鉴定试验的地位和作用,指出在其实施和管理过程中的复杂性。这部分还介绍了承试实验室资质、试验设备使用和管理、试验大纲和试验报告等文件编写和质量控制方面存在的问题,进行分析并提出改进建议。     

多维随机振动试验中的互谱控制技术

文章研究了多维随机振动试验控制中的互谱控制技术,给出控制策略及互谱控制算法,阐述了相关技术。介绍开发出的原理样机构成及控制原理,通过对二维系统的控制试验,验证了控制效果。试验结果表明:采用的控制算法可行,控制方案达到随机控制试验要求。     

直升机低速飞行特性试验分析

低速飞行特性是直升机飞行品质的研究重点之一,低速飞行试验是开展直升机低速飞行特性研究重要手段。首先,从直升机低速飞行特性的主要影响因素和直升机低速飞行的配平操纵两个方面进行理论分析;然后,通过直升机低速前后飞行及侧飞时配平飞行试验,对直升机低速飞行时的配平操纵特性和试验直升机低速特性与尾部气动布局的影响进行分析,提出减小平尾面积或降低初始安装角的尾部气动优化建议,直接指导该型直升机设计和更改。     

无阻流门叶栅式反推力装置数值研究

借助CFD技术对无阻流门叶栅式反推力装置开展了数值研究工作。反推力装置内部流线分布揭示了二次流喷口下游产生的旋涡结构缩减外涵通道正向流通面积、迫使外涵流体由叶栅通道流出产生反推力的流动特征。在叶栅通道结构尺寸一定的情况下,反推力性能由二次流喷射位置、喷射流量、喷射角度共同决定。随着喷射流量的增加,反推力性能提高,且存在一个临界二次流流量;当喷射角度增加,反推力性能反而下降,二次流逆喷产生的效果要优于垂直喷射方式。在二次流流量和角度一定的状况下,喷射位置对旋涡结构和大小没有影响,对外涵通道的堵塞效果却不同,喷射位置倾向于叶栅通道中间位置为佳。     

Variability study of ionospheric total electron content at crest of equatorial anomaly in China from 1997 to 2007

The variation of TEC data at Wuhan station (geographic coordinate: 30.5°N, 114.4°E; geomagnetic coordinate: 19.2°N, 183.8°E) at crest of equatorial anomaly in China from January 1997 to December 2007 were analyzed. Variability with solar activity, annual, semiannual, diurnal and seasonal variation were also analyzed. The MSIS00 model and ISR model were used to analyze the possible mechanisms of the variabilities found in the results. The TEC data in 1997 and 2001 deduced from another crest station Xiamen (geographic coordinate: 24.4°N, 118.1°E; geomagnetic coordinate: 13.2°N, 187.4°E) were used to contrast. Analysis results show that long-term variations of TEC at Xiamen station are mainly controlled by the variations of solar activities. Typical diurnal variation behaves as a minimum of the TEC in the pre-dawn hours around 05:00–06:00LT and a maximum on the afternoon hours around 13:00–15:00LT. Some features like the semiannual anomaly and winter anomaly in TEC have been reported. The anomaly may be the result of common action of the electric field over the magnetic equatorial and the [O/N₂] at the crest station.     

GNSS-R open-loop difference phase altimetry: Results from a bridge experiment

The paper explores a method to obtain accurate lake surface heights using measurements of the Global Navigation Satellite System (GNSS) carrier phase reflected from the lake surface. The method is referred to as Global Navigation Satellite System-Reflection (GNSS-R) open-loop difference phase altimetry method. It consists of two key technologies: one is the open-loop tracking method to track the GNSS-R signals, where the direct GNSS signal’s frequency is used as a reference frequency to obtain the carrier phases of the GNSS-R signals; the other key technology is time difference phase altimetry method to invert the lake surface heights using two or more carrier phases of GNSS-R signals received simultaneously. A validation experiment is carried out on the SANYING bridge over GUANTING lake using a GNSS-R receiver developed by the Center for Space Science and Applied Research (CSSAR), processing the data with GNSS-R open-loop difference phase altimetry method. The lake surface height results are consistent with the height results of GPS dual-frequency differential positioning altimetry. The results show that we can achieve centimeter level height in one minute average, by using 11 minutes carrier phase data of three GNSS-R signals received simultaneously.     

固液推进技术在载人登月中的应用

通过对世界主要航天国家和地区新世纪载人登月计划的研究、美国"阿波罗"飞船登月舱动力系统的详细分析,基于固液推进技术的特点,利用遗传算法开展了固液火箭发动机替代"阿波罗"登月舱下降级和上升级液体火箭发动机方案的优化设计,并对两者在功能、质量、体积和推进剂特性上进行了对比分析.结果表明固液推进技术在载人登月以及深空探测中具有良好的应用优势和前景.     

金属橡胶颗粒静态特性试验

针对目前航空航天领域板壳结构较多,其模态成分密集、振动复杂等问题,提出了一种可用于各种复杂结构振动抑制的新型金属橡胶构件——金属橡胶颗粒.为了解及掌握这种新型金属橡胶构件的性能和设计规律,开展了有关金属橡胶颗粒的静态性能试验研究.通过试验测量了金属橡胶颗粒的静态迟滞回线,获得了金属橡胶颗粒的刚度和阻尼的范围.通过对比不同参数下的刚度和阻尼的试验结果,总结材料参数(丝材、螺旋卷和相对密度)和工艺参数(变形量和安装密度)等对金属橡胶颗粒的刚度特性和阻尼性能的影响规律.金属橡胶颗粒静态特性试验研究为金属橡胶颗粒的设计和工程应用奠定了基础.