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11.
曾一兵%罗正平%李颖%冯伟泉 《宇航材料工艺》2007,37(6):21-24
研究了防静电白色热控涂层(ACR-1)的耐空间环境性能及工艺性能。在模拟空间环境设施中研究了紫外辐照、电子辐照和质子辐照对涂层太阳吸收率(αs)的影响。结果表明ACR-1在地球静止轨道环境中具有较高的稳定性;经过3000当量太阳小时(ESH)的紫外光辐照后,△αs为0.02;质子辐照效应对涂层仅。的变化影响较大。另外,研究了涂层厚度对αs和其与基材结合力的影响,以及基材表面处理工艺对涂层在-196—150℃冷热交变循环试验中可靠性的影响。 相似文献
12.
本文利用欧洲的EISCAT雷达观测资料及与这配合的地磁观测数据,用电离层参数直接计算和地面磁场反演两种方法导出了极区电离层Hall电导率,特别显示出在强对流电场激发的E层等离子体不稳定波对电子加热情况下,电导率明显增高。 相似文献
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航天器在地面待发射期间和空间实际飞行过程中,热控元件光学太阳反射器要遇到各种地面和空间环境,为了航天器的可靠和长寿命,必须对所制备的OSR涂层进行各种地面和空间环境试验并对其各项性能检验与考核,该文就这一系列试验的目的和规范进行了讨论。 相似文献
14.
卫星优化热设计方法 总被引:2,自引:0,他引:2
潘增富 《中国空间科学技术》1993,13(4):1-9
试图把最优化技术应用于卫星工程的热设计中,提出一种优化热设计的方法,并以14个节点模型作为实例进行了计算分析,采用Hooke-Jeeves 的直接搜索法得到了满意的结果。初步编制的计算机程序,可作为卫星热设计方案计算的基础。 相似文献
15.
微重力场中对流—辐射—传质系统的地面模拟技术 总被引:2,自引:0,他引:2
研究了微重力条件下对流-辐射-传质稳态系统的地面相似模拟技术,进一步发 温度-材料综合保护技术。通过采取补偿热流,调整壁面热流密度分布的方法,保持了原型与尺寸适当缩小后的模型的Nu数,Sh数,材料,温度,湿度不变,从而实现模型与原型流动,换热和传质相似。 相似文献
16.
防静电白色热控涂层的空间环境性能试验 总被引:4,自引:0,他引:4
通过在氧化锌晶格中掺入重金属离子,得到具有防静电功能的白色颜料,再以丙烯酸树脂为粘合剂制备出空间飞行器外表面用的ACR-1防静电白色热控涂层;研究了空间环境效应(包括紫外辐照,电子和质子辐照)对该热控涂层太阳吸收率的影响并与有机硅白色热控涂层进行了比较,地面模拟空间环境试验研究结果证明,ACR-1防静电白色热控涂层具有良好的空间稳定性。 相似文献
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18.
《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2020,65(4):1296-1305
This paper aims to study on the cooling effect with two types of water spray nozzle on the flame deflector during the four-engine launch vehicle take-off. To accurately simulate the two-phase flow of the rocket gas with multispecies and the water spray, the three-dimensional compressible Navier-Stokes equations, discrete ordinates methods and realizable k-Ɛ turbulence model are used to establish the rocket supersonic plumes impact model. The Eulerian dispersed phase (EDP) model was used to simulate the water spray into the exhaust gas. The accuracy and effectiveness of the gas-liquid flow model are verified by a good agreement between simulation results and experimental data. On this basis, a series of numerical simulation studies under different water injection position are performed. The results show that the high temperature regions, along the axis of engines on the deflector plate, have no significant temperature decreasing effect by water spray from the nozzles mounted on the apex of the deflector, and the high temperature converts a large quantity of water into vapor near the plume boundary, which would decrease the flow conductivity. With the cooling spray nozzle fixed directly to the deflector plate, the temperature decrease effect is obvious and the effect of thermal shock on deflector plate induced by exhaust plume is reduced, so that it can prevent the flame deflector from thermal ablation. The study results provide indepth information and engineering guidance for designing the water spray systems and increasing the safety of the launch process. 相似文献
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20.
《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2020,65(1):435-445
Strong earthquakes have an impact on the regional thermal radiation background, which has been both observed and confirmed. This effect produces anomalies in the thermal radiation background (TRBA) and increases the difficulty of extracting a thermal radiation anomaly (TRA) that is associated with an earthquake occurring during the same time period. The extraction and identification of such anomalies has been ignored by previous studies. In this study, we investigate the time-frequency analysis (TFA) method, together with the wavelet filtering of the Daubechies method and the relative power spectrum analysis of the Fourier Welch method to extract and analyse the TRBA caused by the 2008 Wenchuan Ms 8.0 earthquake and the TRA of the 2013 Minxian-Zhangxian Ms 6.6 earthquake using data concerning the brightness temperature of a black body (TBB) from the Fengyun-2 series of geostationary meteorological satellites developed by China. The result showed that this method can effectively extract and analyse the TRBA caused by the Wenchuan earthquake and the TRA of the Minxian-Zhangxian earthquake form a complex background environment. Furthermore, we discussed the impact of the earthquake on the TRBA and segmented the process. The impact is mainly reflected by three aspects; the characteristic period of the TRBA changes, the TRBA occurs at the same time every year, which is identical to the time at which the earthquake anomaly occurred, and the impact process is in stages. We also summarized the correlation between the characteristic parameters of a TRA and the regional thermal radiation background, geography, and climatic factors. 相似文献