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111.
M. Nelson W.F. DempsterJ.P. Allen 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,41(5):675-683
Development of reliable and robust strategies for long-term life support for planetary exploration must be built from real-time experimentation to verify and improve system components. Also critical is incorporating a range of viable options to handle potential short-term life system imbalances. This paper revisits some of the conceptual framework for a Mars base prototype which has been developed by the authors along with others previously advanced (“Mars on Earth®”) in the light of three years of experimentation in the Laboratory Biosphere, further investigation of system alternatives and the advent of other innovative engineering and agri-ecosystem approaches. Several experiments with candidate space agriculture crops have demonstrated the higher productivity possible with elevated light levels and improved environmental controls. For example, crops of sweet potatoes exceeded original Mars base prototype projections by an average of 46% (53% for best crop) ultradwarf (Apogee) wheat by 9% (23% for best crop), pinto bean by 13% (31% for best crop). These production levels, although they may be increased with further optimization of lighting regimes, environmental parameters, crop density etc. offer evidence that a soil-based system can be as productive as the hydroponic systems which have dominated space life support scenarios and research. But soil also offers distinct advantages: the capability to be created on the Moon or Mars using in situ space resources, reduces long-term reliance on consumables and imported resources, and more readily recycling and incorporating crew and crop waste products. In addition, a living soil contains a complex microbial ecosystem which helps prevent the buildup of trace gases or compounds, and thus assist with air and water purification. The atmospheric dynamics of these crops were studied in the Laboratory Biosphere adding to the database necessary for managing the mixed stands of crops essential for supplying a nutritionally adequate diet in space. This paper explores some of the challenges of small bioregenerative life support: air-sealing and facility architecture/design, balance of short-term variations of carbon dioxide and oxygen through staggered plantings, options for additional atmospheric buffers and sinks, lighting/energy efficiency engineering, crop and waste product recycling approaches, and human factor considerations in the design and operation of a Mars base. An “Earth to Mars” project, forging the ability to live sustainably in space (as on Earth) requires continued research and testing of these components and integrated subsystems; and developing a step-by-step learning process. 相似文献
112.
为提高航天器热控系统对轨道调整的适应能力,本文研究了与流体回路耦合的可展开式辐射器热控方案在不同轨道高度下的热控性能,分析了不同轨道高度时辐射器面临的热环境的影响,在不同轨道高度下比较了固定辐射器与可展开辐射器的热控特性。结果表明,随着辐射器展开角度的变化,辐射器吸收的空间热流随之发生变化,从而对热控系统的散热能力带来直接影响,调节辐射器的角度可以扩大其对外散热能力。在工程应用中,基于热控流体回路,通过调节可展开式辐射器的展开角度,可以有效提高航天器的轨道热适应能力。 相似文献
113.
114.
Future piloted missions to explore asteroids, Mars, and other targets beyond the Moon will experience strict limitations on communication between vehicles in space and control centers on Earth. These limitations will require crews to operate with greater autonomy than any past space mission has demonstrated. The Antarctic Search for Meteorites (ANSMET) project, which regularly sends small teams of researchers to remote parts of the southern continent, resembles a space mission in many ways but does not rely upon a control center. It provides a useful crew autonomy model for planners of future deep space exploration missions. In contrast to current space missions, ANSMET gives the crew the authority to adjust competing work priorities, task assignments, and daily schedules; allows the crew to be the primary monitor of mission progress; demands greater crew accountability for operational errors; requires the crew to make the most of limited communication bandwidth; adopts systems designed for simple operation and failure recovery; and grants the crew a leading role in the selection and stowage of their equipment. 相似文献
115.
Mostafa El-Alaoui Maha Ashour-Abdalla Jean Michel Bosqued Robert L. Richard 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,41(10):1630-1642
Recent Cluster observations have strongly supported the existence of meso-scale structure in the magnetotail current sheet. In our study, a magnetohydrodynamic simulation event study exhibited current sheet behavior comparable to that seen in the Cluster observations. Geotail and DoubleStar observations also show that the simulation is providing a realistic representation of the magnetosphere during the period of interest; that is, when the current sheet evidently becomes bifurcated. The magnetohydrodynamic simulation allows us to place the local observations into a global contest. It shows that the observations can be explained in terms of localized reconnection tailward of the Cluster location and the formation of a flux rope nearby. The simulation also features wave-like structure across the current sheet. 相似文献
116.
Non-thermal components are key ingredients for understanding clusters of galaxies. In the hierarchical model of structure
formation, shocks and large-scale turbulence are unavoidable in the cluster formation processes. Understanding the amplification
and evolution of the magnetic field in galaxy clusters is necessary for modelling both the heat transport and the dissipative
processes in the hot intra-cluster plasma. The acceleration, transport and interactions of non-thermal energetic particles
are essential for modelling the observed emissions. Therefore, the inclusion of the non-thermal components will be mandatory
for simulating accurately the global dynamical processes in clusters. In this review, we summarise the results obtained with
the simulations of the formation of galaxy clusters which address the issues of shocks, magnetic field, cosmic ray particles
and turbulence. 相似文献
117.
针栓式喷注单元膜束撞击雾化混合过程数值模拟 总被引:5,自引:1,他引:5
为了全面认识针栓式喷注器喷雾场结构,基于自适应网格加密技术和分三相计算的PLIC VOF(Piecewise Linear Interface Calculation Volume of Fluid)方法对针栓式喷注单元膜束撞击雾化混合过程进行了仿真分析,通过对两路推进剂分别进行界面追踪,获得了膜束撞击雾化混合过程的详细结构特征,与高速摄影试验结果定性定量对比均吻合较好,验证了数值方法的准确性。以此为基础对膜束撞击的喷雾场结构、撞击变形过程、流场涡结构、雾化破碎典型特征及破碎后的雾化混合分布特征进行了识别分析,结果表明:膜束撞击形成了液束未穿透液膜和液束穿透液膜2种不同的喷雾扇结构。膜束撞击形成的喷雾扇呈"Ω"形,膜束同时发生弯曲变形和横截面变形。另外,膜束撞击同时受到正压和剪切应力作用,导致了一系列复杂涡流现象,使得相互作用增强,雾化混合均增强,这也是膜束撞击喷注构型优于膜膜撞击的本质原因。最后,还发现膜束撞击喷雾场液滴分布呈现分区结构特征,分别是液束控制主导的上雾化区、液膜控制主导的下雾化区及夹在中间的混合区,实际中应兼顾雾化特性和混合特性,选取中等动量比膜束撞击,这可为针栓式喷注器的理论研究和工程设计提供重要参考。 相似文献
118.
对磁悬浮框架飞轮(MSGFW)和高精度磁轴承研究现状及其未来发展进行了详细阐述。根据转子悬浮力类型,将磁悬浮框架飞轮分为磁阻力构型、洛伦兹力构型和混合力构型,并结合三种构型论述了国内外框架飞轮的发展过程。在此基础上,对球面磁阻力磁轴承和洛伦兹力磁轴承进行了详细介绍,并结合磁路图分析其工作原理,比较了同类磁轴承的优劣。展望了磁悬浮框架飞轮与高精度磁轴承的未来发展方向,指出高动态响应检控共位平动球面磁阻力磁轴承,标准磁悬浮动量球和磁悬浮控制敏感球是磁悬浮框架飞轮的研究重点。 相似文献
119.
Ravi Sood Sean Farrell Paul ONeill Ravi Manchanda N.M. Ashok 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2006,38(12):2779-2781
We have analysed 9 years of data from the All Sky Monitor on the Rossi X-ray Timing Explorer for 2S 0114+650 to study the evolution of its spin, binary, and super-orbital periods. The spin history of the neutron star in this system exhibits torque reversals lasting 1 year. The newly discovered super-orbital period has remained stable over the 9-year span, making 2S 0114+650 the fourth known system to exhibit stable super-orbital modulation. We compare its super-orbital period evolution with those of the other three such systems. 相似文献
120.