共查询到20条相似文献,搜索用时 742 毫秒
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J. Rodriguez V. Lapuerta A. Laveron-Simavilla M. Cordero-Gracia 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2014
An experiment in microgravity conditions aboard the TEXUS-23 mission was performed to obtain the deformation up to breakage of a cylindrical liquid column in isorotation around an eccentric axis. In previous work, breakage rotation speed was predicted by a numerical method. This method was validated by comparison with analytical and experimental results. The non-symmetric breakage of the liquid column observed in the experiment, however, was not explained by the combined effect of rotation and eccentricity. 相似文献
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V. Lapuerta A. Lavern-Simavilla J. Rodríguez 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,41(12):2137-2144
A cylindrical liquid bridge supported between two circular-shaped disks in isorotation is considered. The effect of an offset between the rotation axis and the axis of the two supporting disks (eccentricity) on the stability of the static liquid bridge is investigated. A numerical method is used to find stable and unstable shapes and to determine the stability limit for different values of eccentricity. The calculated stability limits are compared with analytical results, recovering the same behavior. Numerical results have been also compared with the results of an experiment aboard TEXUS-23, recovering the stability limit and the equilibrium shapes. 相似文献
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通过对文丘利管的工作原理的分析,阐明了文丘利管在液氮系统中所起的作用,提出了文丘利管的设计计算方法。通过对现有设备液氮系统的改造,对该系统及文止利管进行了试验验证工作。这些工作所得到的结论对新型环境模拟设备液氮系统的设计提供了重要的参考依据。 相似文献
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大容量推进剂贮箱液体晃动性能试验 总被引:1,自引:0,他引:1
对某种内带推进剂管理装置(PMD)的大容量推进剂贮箱内液体晃动性能进行试验.开展不同充液比工况下空壳贮箱液体晃动试验,分析比较晃动试验结果与采用等效动力学模型的液体晃动理论计算结果,两者结果一致吻合,试验系统可靠性和理论模型的正确性得到良好验证.然后开展了不同充液比工况下内带PMD贮箱液体晃动试验,试验结果表明贮箱内液体晃动性能受内部PMD结构影响明显.该试验研究结果为运载火箭和卫星的姿态和轨道控制系统的设计优化提供重要参考和数据支撑. 相似文献
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介绍了气体注入压力激励方法测量卫星液体推进剂剩余量地面模拟试验;给出了包括温度、压力变化特性,采样数据选择,试验结果等方面的详细情况;常规模型模拟测量结果表明,可以实现不确定度小于贮箱总体积1.0%的高精度测量。 相似文献
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微重力环境下半球形贮箱液体重定位试验研究 总被引:1,自引:0,他引:1
本文利用落塔形成的微重力环境,对半球形贮箱中液体重定位问题进行了试验研究。所用液体与半球形箱壁之间的接触角为零并在加载前形成了失重初始凹液面.本试验分侧向不加干扰及加干扰两种初始条件.通过高速摄影机观察了液体重定位的全过程并测量了重定位流速和重定位时间。试验结果表明,液体重定位呈壁流流型.实测重定位时间与理论估算值一致. 相似文献
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液体冷却罩是CCPL与CPL的主要区别之一 ,文章概述了液体冷却罩的主要作用和设计过程 ,讨论了液体冷却罩的不同结构设计方案 ,分析了它们的特性 ,通过比较认为 ,当工作环境与CCPL传输距离不同时 ,可选择不同结构的液体冷却罩 ,其中 ,由冷凝管道提供冷负荷的液体冷却罩设计方案是一种最具有前途的设计方案。 相似文献
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N. Mireault G. Abel L. Andrzejewski G.G. Ross 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,41(12):2150-2160
A setup called Controlled Rotation of Liquids (CROL) has been developed and used to investigate rotational behavior of liquids interacting with solids under reduced gravity conditions. The CROL setup allows us to evaluate the acceleration needed to overcome the interfacial forces that hinder liquid displacement inside different size containers. The well known Wilhelmy equation is used to explain the experimental results. Comparison between experimental results and theoretical predictions are presented and discussed. 相似文献
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Qi-Sheng Chen Ya-Chao Liu 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,41(12):2126-2130
Linear stability analysis was performed to study the mechanism of transition of thermocapillary convection in liquid bridges with liquid volume ratios ranging from 0.4 to 1.2, aspect ratio of 0.75 and Prandtl number of 100. 2-D governing equations were solved to obtain the steady axi-symmetric basic flow and temperature distributions. 3-D perturbation equations were discretized at the collocation grid points using the Chebyshev-collocation method. Eigenvalues and eigenfunctions were obtained by using the Q–R method.The predicted critical Marangoni numbers and critical frequencies were compared with data from space experiments. The disturbance of the temperature distribution on the free surface causes the onset of oscillatory convection. It is shown that the origin of instability is related to the hydrothermal origin for convections in large-Prandtl-number liquid bridges. 相似文献
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研究了全尺度重力探测卫星-B贮箱对于安装档板和不安装挡板情形下液体推进剂晃动的液体动力特性。结果显示,以重力瞬变加速度和重力梯度加速度为作用力的轨道加速度使液体推进剂产生了晃动,安装挡板使晃动幅度减小。由于推进剂在贮箱中上下运动的同时伴随着左右运动而产生了作用于贮箱上的力,通过液体推进剂与贮箱壁面的应力关系计算了作用在贮箱上的力。计算模拟结果显示,挡板产生的阻尼在减少流体晃恸 的同时也减少了流体作 相似文献
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干扰因素对液体火箭发动机性能的影响 总被引:2,自引:1,他引:2
给出并改进了描述液体火箭发动机稳态工况的非线性数学模型;用修正的Gauss-Newton法求解各性能参数,分析了每个干扰因素分别对液体火箭发动机参数的影响,用非线性模型和小偏差方法对比分析了两个干扰因素分别和共同对发动机参数的影响;所得结论可用于发动机试验结果分析、发动机可靠性分析、发动机故障分析,也可用于揭示发动机参数随各种干扰因素的变化规律 相似文献
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以天舟一号货运飞船为依托,开展空间蒸发相变传热规律的科学实验研究,探索重力对蒸发传热传质过程的影响规律.设计了一套地面蒸发实验平台,以蒸发相变液体FC-72为研究对象,通过红外热像仪测温、热流量计、差分热电偶等手段,观测FC-72液层在不同台面温度、注液量等情况下的相变界面变化、蒸发表面特性、流体物性及Marangoni对流涡胞的变化等,获取其蒸发两相流体的液层温度差、表面温度场、热流量值、蒸发速率和涡胞结构等.实验结果表明:在其他条件不变的情况下,FC-72液层与蒸发台面的温差越高,其蒸发速率越快;注液量越大,蒸发速率也越大;在蒸发过程中出现了浮力对流涡胞和Marangoni对流涡胞.此外,通过地面蒸发实验可以确定空间科学实验选用的实验介质和材料,进而优化确定空间科学实验的工况、参数及流程等,部分地面实验结果也将直接成为天地对比实验的科学成果. 相似文献
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孙国江 《中国空间科学技术》1996,16(1):52-57
根据流体域控制方程、结构动力学方程和液体与固体接触界面的条件,建立了液体燃料与卫星结构耦合振动有限元方程,并举出一些算例。根据算例结果讨论了对带有大量液体燃料卫星的液体燃料和结构耦合振动问题以及在卫星研制阶段进行耦合振动分析的重要性。 相似文献
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P.K. Karmakar M. Maiti S. Sett C.F. Angelis L.A.T. Machado 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
A multi-channel microwave radiometre (make: Radiometrics Corporation) is installed at Instituto Nacional de Pesquisas Espaciais–INPE, Brazil (22°S). The radiometric output of two channels of the radiometer in the form of brightness temperature at 23.834 GHz and 30 GHz, initially, were used to find out the ambient water vapor content and the non-precipitable cloud liquid water content. The necessary algorithm was developed for the purpose. The best results were obtained using the hinge frequency 23.834 GHz and 30 GHz pair having an r.m.s. error of only 2.64. The same methodology was then adopted exploiting 23.034 GHz and 30 GHz pair. In that case the r.m.s. error was 3.42. These results were then compared with those obtained over Kolkata (22°N), India, by using 22.234 GHz and 31.4 GHz radiometric data. This work conclusively suggests the use of a frequency should not be at the water vapor resonance line. Instead, while measuring the vapor content for separation of vapor and cloud liquid, one of them should be a few GHz left or right from the resonance line i.e., at 23.834 GHz and the other one should be around 30 GHz. 相似文献
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空间环境模拟器液氮系统数学模型 总被引:1,自引:1,他引:0
贾阳 《中国空间科学技术》1996,16(5):1-11
大型空间环境模拟器的液氮系统庞大复杂,为满足确定控制方案、建立故障诊断模型、技术改造等的需要,建立液氮系统的数学模型是十分必要的。以某空间环境模拟器的液氮系统为例,建立了液氮系统的数学模型;分析了系统输入参数对系统输出参数影响;最后,应用这个模型,得到了一些有益的结论,提出了一种调节阀的准稳态控制方法。 相似文献