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The paper describes the basic definition and application of 'Cost Engineering' which means to design a vehicle system for minimum development cost and/or for minimum operations cost. This is important now and for the future since space transportation has become primarily a commercial business in contrast to the past where it has been mainly a subject of military power and national prestige. Several examples are presented for minimum-cost space launch vehicle configurations, such as increasing vehicle size and/or the use of less efficient rocket engines in order to reduce development and operations cost. Further a cost comparison is presented on single-stage (SSTO)-vehicles vs. two-stage launchers which shows that SSTOs have lower development and operations cost although they are larger, respectively have a higher lift-off mass than two-stage vehicles with the same performance. The design of a space tourism-dedicated launch vehicle is an extreme challenge for a cost-engineered vehicle design in order to achieve cost per seat not higher than $50,000. Finally an outlook is presented on the different options for manned Earth-to-Moon transportation modes and vehicles – another most important application of 'cost engineering', taking into account the large cost of such a future venture. 相似文献
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《中国航天(英文版)》2016,(4)
The research status on the development of RBCC engines and corresponding aerospace vehicles around the world was overviewed,and the technical and application characteristics of RBCC technology were summarized.New development trends of combined cycle engines as well as space transportation were analyzed,and lastly,some suggestions on the development of RBCC and the relative aerospace vehicles were proposed. 相似文献
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为研究烃类推进剂航天动力技术在中国的后续发展和未来应用方向,对比分析煤油、甲烷和丙烷等典型烃类推进剂的物理化学性质和应用特性,简要介绍烃类推进剂航天动力在一次性运载火箭、可重复使用运载器、高性能上面级推进、无毒空间推进和吸气式推进领域的发展动态及应用状况。当前国内外航天动力系统的发展和应用情况表明,以液氧煤油发动机和液氧甲烷发动机为代表的烃类推进剂航天动力将引领未来高性能低成本航天推进系统的发展趋势,依照中国液氧/烃火箭发动机的研制进展和技术水平,以其为核心的新型动力体系在中国未来的天地往返、载人登月和深空探测等多任务适应性方面具有良好应用前景。 相似文献
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中国重型运载火箭动力系统研究 总被引:3,自引:0,他引:3
分析了未来航天发展趋势,指出为实现载人登月和深空探测,发展重型运载火箭,研制大推力火箭发动机势在必行.提出了中国重型运载火箭主动力--_1500吨级液氧煤油发动机和200吨级液氧液氢发动机的总体方案,确定了发动机的主要参数,明确了发动机的关键技术,考虑了发动机的研制条件,进行了发动机研制策划.根据中国的技术水平和经济实... 相似文献
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为提高火箭基冲压组合循环(RBCC)发动机火箭冲压模态下火箭推力增益,基于模拟飞行Ma=4来流条件的数值计算结果,分析了火箭射流与冲压主流超/超剪切流动的特性,探讨了火箭推力增益的组成,并给出了提高火箭推力增益的措施:1)冲压流道、火箭工作参数的选取必须确保两股超声速剪切流之间的流动匹配,在有限空间内快速、低损的实现高能火箭射流与低能冲压主流间的动量及质量输运,最大限度地提高发动机喷管排气速度及压力;2)采用高室压火箭,通过增加推力室室压,提高火箭燃气膨胀程度,减小火箭推力增益损失。 相似文献
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国外小推力液体火箭发动机的最新进展 总被引:7,自引:0,他引:7
小推力液体火箭发动机用于航天飞机、宇宙飞船、航天运载器等航天器的轨道和姿态控制、对接、交会等。主要介绍美国、法国、俄罗斯对小推力发动机的研制情况,以及这些国家所研制的这类发动机的性能和特点。 相似文献
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在我国的载人登月技术方案中,为实现软着陆,登月舱需要一种大推力、高性能、多次起动,能够大范围变推力的泵压式发动机.通过研究国外登月用下降级发动机技术发展现状和趋势,基于我国氢氧发动机和低温推进剂空间贮存水平,进行了深度变推发动机的系统方案研究;通过分析比对燃气发生器循环和膨胀循环系统优缺点,确定发动机系统方案为涡轮串联闭式膨胀循环;采用空间可长时间贮存的液氧/甲烷推进剂组合,可满足任务周期要求;根据推力深度调节时对各组合件性能要求,确定喷注器燃烧稳定技术和燃烧室身部传热技术是深度变推发动机研制的核心关键技术. 相似文献
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大推力火箭发动机是航天发展的基础,是国家高科技水平和综合国力的体现。分析了运载火箭主动力发展的现状和趋势,指出大推力液氧煤油发动机和液氧液氢发动机是发展方向和最佳组合。提出了我国重型运载火箭大推力液氧煤油发动机和液氧液氢发动机的总体方案和主要参数,研究了两种发动机的关键技术及其解决途径。这两种大推力发动机的研制,将为我国载人登月、深空探测等重大航天活动和空间利用提供动力支撑。 相似文献
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This article reports about the results of the latest computer runs of a lunar base simulation model. The lunar base consists of 20 facilities for lunar mining, processing and fabrication. The infrastructure includes solar and nuclear power plants, a central workshop, habitat and farm. Lunar products can be used for construction of solar power systems (SPS) or other spacecraft at several space locations. The simulation model evaluates the mass, energy and manpower flows between the elements of the system as well as system cost and cost of products on an annual basis for a given operational period. The 1983 standard model run over a fifty-years life cycle (beginning about the year 2000) was accomplished for a mean annual production volume of 78 180 Mg of hardware products for export resulting in average specific manufacturing cost of 8.4 $/kg and total annual cost of 1.25 billion dollars during the life cycle. The reference space transportation system uses LOX/LH2 propulsion for which at the average 210 500 Mg LOX per year is produced on the moon. The sensitivity analysis indicates the importance of bootstrapping as well as the influence of market size, space transportation cost and specific resources demand on the mean lunar manufacturing cost. The option using lunar resources turns out to be quite attractive from the economical viewpoint. Systems analysis by this lunar base model and further trade-offs will be a useful tool to confirm this. 相似文献
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The concept of “space patrol” is considered, aimed at discovering and cataloging the majority of celestial bodies that constitute
a menace for the Earth [1, 2]. The scheme of “optical barrier” formed by telescopes of the space patrol is analyzed, requirements
to the observation system are formulated, and some schemes of sighting the optical barrier region are suggested (for reliable
detection of the celestial bodies approaching the Earth and for determination of their orbits). A comparison is made of capabilities
of electro-jet engines and traditional chemical engines for arrangement of patrol spacecraft constellation in the Earth’s
orbit. 相似文献
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《中国航天(英文版)》2021,(2)
Throttling of large-thrust liquid rocket engines, which can improve mission adaptability of a carrier rocket, reduce risk and facilitate rocket recovery, is a key technology for current and future space development. This paper summarizes the state of the art and trends of throttling technology for large-thrust liquid rocket engines at home and abroad. According to the working principles of propulsion for rocket engines, throttling the propellant flow rate is a major way of adjusting thrust, and regulation devices along with adjustable injectors are primary measures of throttling propellant flow rates. This paper clarifies the working principles of typical regulation devices and adjustable injectors, introduces the regulation schemes of typical large-thrust engines such as YF-100, RD-170, and SSME, and summarizes the main characteristics of current throttleable large-thrust engines. Finally, critical technologies and development trends of throttling are discussed, including combustion stability and reliable cooling of thrust chambers at low thrust levels, turbopump stability, and stable regulation and precise control in a wide range of operating conditions. 相似文献
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Julin Hermida 《Space Policy》1997,13(2):145-152
The article explores the way so-called legal space risks are managed in US commercial space transportation. Risk management in the space transportation field is a highly regulated process, thus allowing practically no possibility of deviating from the system stemming from such regulation. Such a system arises from the legislation, basically the Commercial Space Launch Act, and the agreements. This risk-management structure is characterized by the transfer of risks from the space launch provider to both the user and the government and by the ensuing launcher's limitation of liability. 相似文献
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T. M. Eneev 《Cosmic Research》2005,43(6):383-387
Two problems in studying deep space are discussed that are, in the author's opinion, the most important. The first is soil sampling from the smaller bodies of the Solar System, such as the Martian satellite Phobos and asteroids of groups C and S of the Main Asteroid Belt. This soil (so-called primordial substance) can help to elucidate some problems of the Solar System's formation; in particular, to construct a reliable model of the internal structure of the Earth. The second problem is to reveal all sufficiently large asteroids penetrating inside the Earth's orbit and to catalog those asteroids that are hazardous from the viewpoint of collision with the Earth. To this end, it is suggested to launch five or six Earth-orbiting spacecraft with telescopes capable of recording objects down to a brightness of 22– 25 m . It is pointed out that both problems can be solved in the near future using comparatively cheap standardized space vehicles launched into near-Earth orbits by the Soyuz carrier rocket and boosted further by electro-jet engines of small thrust. 相似文献
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US Office of Technology Assessment 《Space Policy》1995,11(4):283-287
Below is a summary of what was to be the first in a series of reports produced by the Office of Technology Assessment (now defunct) on policy for the USA's future space transportation technology and industrial base. It examines the Clinton Administration's 1994 National Space Transportation Policy and supporting implementation plans and raises and analyses such issues as conflicts and redundancies within NASA and DoD space transportation development programs; competition and cooperation with foreign launch vehicle and component providers; US government limits on the conversion of long-range missiles to space launchers in the face of Russian activity in this area; and the effectiveness of Administration efforts to include the private sector in space transportation decision making. Some issues not covered in the Policy are also discussed. 相似文献
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In 1996 the NASA Advisory Council asked for a comprehensive look at future launch projections out to the year 2030 and beyond. In response to this request NASA sponsored a study at The Aerospace Corporation to develop long-range space transportation models for future commercial and government applications, and to analyze the design considerations and desired characteristics for future space transportation systems. Follow-ons to present space missions as well as a wide array of potential new space applications are considered in the study. This paper summarizes the space transportation system characteristics required to enable various classes of future missions. High reliability and the ability to achieve high flight rates per vehicle are shown to be key attributes for achieving more economical launch systems. Technical, economic and policy implications are also discussed. 相似文献
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《Acta Astronautica》2007,60(10-11):801-809
The main task of this paper is to compare two types of low thrust rocket engines: constant thrust vs. variable-thrust engines. We will be concerned with efficiency, where efficiency is evaluated in the case of the orbit-to-orbit transfer with maximum payload mass in the central Newtonian gravity field. The launch mass of the space vehicle is supposed to be fixed. The traditional solution is the decomposition of the problem into parametric and dynamical parts. The corresponding variational problems differ for two rocket thruster types under consideration. We propose change of variables, which makes it possible to reduce averaged equations of optimal motion of a spacecraft with the mentioned engines to the unified form. Using this unified form comparison of the performance of constant- and variable-thrust engines is conducted. 相似文献
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In 1996 the NASA Advisory Council asked for a comprehensive look at future launch projections out to the year 2030 and beyond. In response to this request NASA sponsored a study at The Aerospace Corporation to develop long-range space transportation models for future commercial and government applications, and to analyze the design considerations and desired characteristics for future space transportation systems. Follow-ons to present space missions as well as a wide array of potential new space applications are considered in the study. This paper summarizes the space transportation system characteristics required to enable various classes of future missions. High reliability and the ability to achieve high flight rates per vehicle are shown to be key attributes for achieving more economical launch systems. Technical, economic and policy implications are also discussed. 相似文献