直升机气动干扰实验研究

本文介绍了一个模型直升机气动干扰实验研究的概况,给出了有和没有旋翼时平尾法向力时均值的比较。旋翼拉力系数对平尾法向力时均值的影响,平尾法向力的时间历程等。通过平尾法向力计算结果与实验结果的比较,说明在低风速时的平尾法向力计算中考虑旋翼下洗对动压的影响是重要的。     

飞机抛物线飞行试验中的液体行为仿真

微重力环境下液体的流动特性和晃动行为是航天工程上颇为关心的问题,也是进行推进剂管理的基础。飞机抛物线飞行是创建微重力环境地面实验方法之一,可实现对一定时间内液体行为的观测,但其成本较高且试验时长受限。基于失重飞机的一般运动规律,对单次及多次抛物线飞行的任务剖面进行了设计,并以单次抛物线飞行为例、利用CFD软件对液体行为进行了数值仿真,分析了失重飞行段初始条件对微重力液体响应的影响。仿真结果可为失重飞机飞行任务剖面的设计和优化提供参考。     

低温推进剂输送管绝热试验研究

用量热法分别测试了低温推进剂输送管聚氨酯发泡塑料绝热层和CC2冷凝真空绝热层的热导率。结果表明：聚氨酯发泡塑料具有一定的绝热效果，C02冷凝真空绝热层的绝热效果更好，但CO2冷凝真空绝热的工艺实施较难。工程上低温推进剂输送管可采用聚氨酯发泡塑料进行绝热。     

双级气流场压力解耦控制研究

针对温度、压力、湿度多参数复合计量检定装置中双温双压法湿度发生的上级饱和气体压力和下级实验舱气体压力控制具有强耦合关系,提出了一种基于对角矩阵的双极气流场解耦方法。该方法利用理想气体状态方程和调节阀流量特性建立双输入双输出气流场控制模型,运用对角矩阵法将原系统变为两个独立的单输入单输出控制系统,消除两者之间的耦合关系。实验结果表明:该方法取得了很好的效果,饱和器和实验舱的压力控制稳态精度都得到大幅度提高。     

Evaluation of Characteristics of Non-Metallic Inclusions in P/M Ni-Base Superalloy by Automatic Image Analysis

Non-metallic inclusions,especially the large ones,within P/M Ni-base superalloy have a major influence on fatigue characteristics,but are not directly measurable by routine inspection.In this paper,a method,automatic image analysis,is proposed for estimation of the content,size and amount of non-metallic inclusions in superalloy.The methodology for the practical application of this method is described and the factors affecting the precision of the estimation are discussed.In the experiment,the characteristics of the non-metallic inclusions in Ni-base P/M superalloy are analyzed.     

空气动力试验中的计量监督与保障

以具体事例说明了计量在空气动力试验中的作用，简述了对基地计量体系建立与发展的认识和体会。     

Plant mineral nutrition,gas exchange and photosynthesis in space: A review

Successful growth and development of higher plants in space rely on adequate availability and uptake of water and nutrients, and efficient energy distribution through photosynthesis and gas exchange. In the present review, literature has been reviewed to assemble the relevant knowledge within space plant research for future planetary missions. Focus has been on fractional gravity, space radiation, magnetic fields and ultimately a combined effect of these factors on gas exchange, photosynthesis and transport of water and solutes.     

Physics results with the ARGO-YBJ experiment

ARGO-YBJ is a multipurpose experiment consisting in a dense sampling air shower array with 93% sensitive area located at very high altitude. The apparatus is in stable data taking since November 2007 at the YangBaJing Cosmic Ray Laboratory (Tibet, PR China, 4300 m a.s.l., 606 g/cm²). In this paper we report the main results in Gamma-Ray Astronomy and Cosmic Ray Physics after about 3 years of operation.     

Detection of the high energy component of Jovian electrons in Low Earth Orbit with the PAMELA experiment

The PAMELA experiment is devoted to the study of cosmic rays in Low Earth Orbit with an apparatus optimized to perform a precise determination of the galactic antimatter component of c.r. It is constituted by a number of detectors built around a permanent magnet spectrometer. PAMELA was launched in space on June 15th 2006 on board the Russian Resurs-DK1 satellite for a mission duration of 3 years. The characteristics of the detectors, the long lifetime and the orbit of the satellite, will allow to address several aspects of cosmic-ray physics. In this work we discuss the observational capabilities of PAMELA to detect the electron component above 50 MeV. The magnetic spectrometer allows a detailed measurement of the energy spectrum of electrons of galactic and Jovian origin. Long term measurements and correlations with Earth–Jupiter 13 months synodic period will allow to separate these two contributions and to measure the primary electron Jovian component, dominant in the 50–70 MeV energy range. With this technique it will also be possible to study the contribution to the electron spectrum of Jovian e⁻ reaccelerated up to 2 GeV at the Solar Wind Termination Shock.     

航空发动机涡轮机匣温度试验对比验证研究

涡轮机匣结构复杂且工作环境比较恶劣,直接利用发动机部件开展机匣表面换热规律研究难度极大.通过采用简化模型的基础研究结合某发动机部件试验验证的方式进行研究.在基础研究中,取涡轮机匣的1个周期性扇段作为研究对象,对机匣结构中的一些圆弧、倒角、倒圆等结构进行了简化,采用数值计算和瞬态液晶测试技术获得了涡轮机匣表面换热经验关系式;在验证试验中,针对某发动机部件,在压力和温度均接近发动机工况下进行试验,获得了涡轮机匣表面换热情况,并对基础研究获得的经验关系式进行了验证.研究结果表明:基础研究获得的换热经验关系式在发动机部件试验中同样适用.应用的研究方法可供类似研究借鉴.