垂直起降可重复使用运载器发展现状与关键技术分析

重复使用运载技术是降低单次发射成本、提高发射密度和减少残骸危害的有效手段,随着以Falcon 9系列为代表的垂直起降运载器的成功回收与重复使用,其在商业航天发射市场表现出了较强的竞争力,掀起了可重复使用运载器的研究新热潮。首先梳理了垂直起降可重复使用运载器的发展现状,然后结合垂直起降运载的任务特征分析了其关键技术,最后总结了垂直起降运载器的发展趋势。     

The impact of launch vehicle type and size on development cost

The technical development trend of future launch vehicle systems is towards fully reusable systems, in order to reduce space transportation cost. However, different types of launch vehicles are feasible, as there are

• —winged two-stage systems (WTS)

• —ballistic single-stage vehicles (BSS)

• —ballistic two-stage vehicles (BTS)

The performance of those systems is compared according to the present state of the art as well as the development cost, based on the “TRANSCOST-Model”. The development costs are shown versus launch mass (GLOW) and pay-load for the three types of reusable systems mentioned above.It is shown that performance optimization and cost minimization lead to different results. It is more economic to increase the vehicle size for achieving higher performance, instead of increasing technical complexity.Finally it is described that due to the essentially lower launch cost of reusable vehicles it will be feasible to recover the development cost by an amortization charge on the launch cost. This possibility, however, would allow commercial funding of future launch vehicle developments.     

Economics of telecommunications space segments

This paper proposes a complete model for assessing the economics of telecommunications satellite systems, accounting for spacecraft development and manufacturing, launch and operations in orbit. This allows to account for such parameters as the mass and lifetime of the satellites, the number and type of payloads, the number of satellites procured and launched, the spare policy, the launch vehicle, the insurances, the satellite average MTTF and the management of the space segment efforts.

The model is divided into four parts: the spacecraft mass model, the spacecraft procurement cost model, the MTTF model and the space segment cost-effectiveness model. It provides for the rapid solution of a number of problems within a wide range of parameters such as assessing the influence on space segment economics of —certain satellite technologies, —satellite and payload mass, —number of payloads per spacecraft, —satellite lifetime, or —spare policy.     

Cost Engineering – The new paradigm for space launch vehicle design

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.     

Economy of modular low-technology launch vehicles

The paper comprises an assessment of the design and the economics of so-called “low-cost” simple modular launch vehicles. It is shown that the performance is very marginal and that the cost per launch cannot compete with technically more advanced fully reusable vehicles. Especially a private-funded development cannot be amortized economically in case of an expendable launch vehicle.     

Simulation model for the operation of space freighters

This paper makes the attempt to illustrate the need for a detailed operational analysis of future space transportation systems with the help of computer-based simulation models. The basic approach deemed suitable for such a systems simulation is explained in some detail. A reference program (100,000 Mg payload per year during 25 years) for a reference mission (heavy cargo transport to GEO for SPS construction) has been selected. A base-line launch vehicle (fully reusable ballistic all chemical three stage vehicle) has been defined, which is considered a serious applicant for such a mission. It was found that the take-off mass of this type of vehicle should be as large as practical from the viewpoint of cost-effectiveness. The example chosen has a GLOW of 10,000 Mg and lifts more than 100 Mg to GEO.With consideration of the operational parameters the simulation model evaluates the annual production rates, inventory of stages, utilization of facilities and operational cost, which amount within this frame of reference to about 96 $/kg net payload delivered to GEO in terms of 1980 dollars and contribute the main share to the total transportation cost.     

Low Cost and Reusability of Launch Vehicle

This paper analyzes the launch price of the launch vehicles, domestic and abroad, studies the status and trend of the low cost launch vehicles, and introduces two measures to reduce the cost by means of evolved and disruptive technologies, utilizing the concept of low cost manufacturing and operating modes as well. This paper also analyzes the launch strategies for small satellites such as piggyback, networking launch, and single launch with a small launch vehicle(SLV). Finally, the development trend of reusable launch vehicles is discussed as well as the development prospects for China's reusable launch vehicle.     

VEGA, a small launch vehicle

Several studies have been performed in Europe aiming to promote the full development of a small launch vehicle to put into orbit one ton class spacecrafts. But during the last ten years, the european workforce was mainly oriented towards the qualification of the heavy class ARIANE 5 launch vehicle.Then, due also to lack of visibility on this reduced segment of market, when comparing with the geosatcom market, no proposal was sufficiently attractive to get from the potentially interrested authorities a clear go-ahead, i.e. a financial committment.

The situation is now rapidly evolving. Several european states, among them ITALY and FRANCE, are now convinced of the necessity of the availability of such a transportation system, an important argument to promote small missions, using small satellites. Application market will be mainly scientific experiments and earth observation; some telecommunications applications may be also envisaged such as placement of little LEO constellation satellites, or replacement after failure of big LEO constellation satellites.

FIAT AVIO and AEROSPATIALE have proposed to their national agencies the development of such a small launch vehicle, named VEGA.

The paper presents the story of the industrial proposal, and the present status of the project: Mission spectrum, technical definition, launch service and performance, target development plan and target recurring costs, as well as the industrial organisation for development, procurement, marketing and operations.     

International market for a reusable launch vehicle

A reusable launch vehicle could be developed early next century if the X-33 program is successful. Its development will be funded by industry, and the vehicle will be operated privately. A critical task is to assess the future market for such a vehicle. The total number of commercial payloads could range between 40 and 60 satellites per year, taking into account the market elasticity due to the launch price reduction. The RLV would face important competition from expendable launch vehicles. However, the RLV could capture two-thirds of this market, or 26–33 commercial payloads per year.     

我国可重复使用液体火箭发动机发展的思考

重复使用是降低航天发射成本的重要途径之一,是液体火箭发动机未来发展的重要方向。本文分析了可重复使用液体发动机的发展趋势,针对可重复使用运载器对发动机功能的需求,探讨了动力系统方案;对比了液氧煤油和液氧甲烷等推进剂组合和不同循环方式,认为几种发动机方案均可满足重复使用运载器的需求;研究了重复使用发动机的关键技术,提出应重点研究可重复使用液体火箭发动机高温组件热结构疲劳寿命评估及延寿技术、运动组件摩擦磨损技术、结构动载荷控制与评估技术、快速检测评估与维修维护技术、健康监控与故障诊断技术、二次或多次起动技术与大范围推力调节技术等。     

运载火箭贮箱增压控制技术发展综述

随着运载火箭低成本、高可靠性的发展趋势,对贮箱增压的控制技术提出了更高的要求。在研究国内外火箭的增压控制技术现状的基础上,总结提炼出增压控制技术的发展趋势,为后续新型火箭的研制提供参考。     

A cost-engineered launch vehicle for space tourism

The paper starts with a set of major requirements for a space tourism vehicle and discusses major vehicle options proposed for this purpose. It seems that the requirements can be met best with a Ballistic SSTO Vehicle which has the additional advantage of lowest development cost compared to other launch vehicle options — important for a commercial development venture.

The BETA Ballistic Reusable Vehicle Concept is characterized by the plug nozzle cluster engine configuration where the plug nozzle serves also as base plate and re-entry heat shield. In this case no athmospheric turn maneuver is required (as in case-of the front-entry Delta-Clipper DC-Y concept). In our specific case for space tourism this mode has the avantage that the forces at launch and reentry are in exactly the same direction, easing passenger seating arrangements. The second basic advantage is the large available volume on top of the vehicle providing ample space for passenger accomodation, visibility and volume for zero-g experience (free floating), one of the major passenger mission requirements. An adequate passenger cabin design for 100 passengers is presented, as well as the modern BETA-STV Concept with its mass allocations.     

可重复使用运载火箭着陆支腿总体布局与关键参数优化

通过对着陆支腿数量和构型进行对比仿真分析,提出了可重复使用运载火箭着陆支腿的总体布局方案,同时建立了着陆支腿参数化仿真模型,将着陆支腿的关键几何参数作为决策变量,基于多体动力学仿真软件开展着陆稳定性仿真分析,以提高着陆稳定性、降低运载火箭返回级受到的着陆过载系数及支腿轻量化为优化目标,对着陆支腿关键几何参数进行优化和确定。仿真结果表明,优化结果能够满足工程使用需要,可以为可重复使用运载火箭着陆支腿总体方案设计提供参考。     

Simplified parametric cost trade-offs in satellite system design

In this paper, a parametric cost model for the space segment of a meteorological satellite system is derived and exercised to provide insight into the major economic trade-offs affecting the choice of the satellite's design life and replacement strategy. Trade-offs involving replacement strategy include launch via an expendable booster versus launch via the Space Shuttle; and recovery, repair, and reuse of a failed satellite versus simple replacement with no reuse.

The sensitivities of space segment costs to design life, launch costs, replacement costs, and refurbishment costs are examined with explicit inclusion of nonrecurring and recurring costs.

The results from an application of the model indicate that routine spacecraft retrieval and reuse of a modestly expensive spacecraft is not a significant economic benefit and that design lifetimes of three or four years are the best choice.     

Some problems of selection and evaluation of the Martian suit enclosure concept

One of the most important tasks for preparation of a future manned mission to Mars is to create a space suit, which ensures efficient and safe operation of the man on the planet surface.

The concept of space suit (SS) utilisation on the Mars surface will be determined mainly by the Mars mission scenario. Currently the preference is given to utilisation of robotics with the crew driving a Mars rover vehicle, whereby the suit will be used solely as an additional safety means.

However, one cannot exclude the necessity of a durable self-contained stay of the man outside a pressurised compartment, to pick up, for instance, soil samples or do certain repair work in case of an emergency.

The requirements to the Mars suit and especially to the personal self-contained life support system (LSS) will depend in many respects on the Mars environmental conditions, the space vehicle system concept and performance characteristics, the airlock and its interface design, the availability of expendable elements for the LSS, etc.

The paper reviews principal problems, which have to be solved during development of the Martian suit. A special attention is paid to the issue of suited man mobility during traversing on the planet surface.

The paper also reviews the arguments for application of a suit semi-rigid design concept and evaluates potentialities of using certain elements of the existing “Orlan” type suit.

The paper presents results of a number of studies on selection of the planetary SS enclosure concept and on experimental evaluation of mobility of the lower torso and leg enclosures in conjunction with a specially designed prototype model (tentative model) of the SS enclosure.     

An alternative to Hermes a solution for the European space industry

A variety of valuable roles can be foreseen during the next two decades for a reusable, piloted launch vehicle with a small payload. The authors argue that unfortunately, as currently proposed, the Hermes-Ariane 5 vehicle will not be able to fill the roles required. The authors propose a reusable aerospace transporter-a variant of Hermes - which will provide a solution and allow Europe to take the lead in developing the first fully reusable launch vehicle.     

New Power for Boosting China's Aerospace Industry

China's new-generation launch vehicle LM-5 successfully completed its maiden launch in November 2016.Among the new technologies applied in the launch vehicle,four types of liquid rocket engines attracted extensive attention.These engines feature advanced concepts and technologies such as a staged combustion cycle and expander cycle.The engines are the results of hard effort of more than ten years,which is also an epitome of the development history of China's aerospace industry.This paper gives a brief introduction to the technological schemes,main parameters,development process and application of the four types of engines that powered the new-generation launch vehicle.Finally,proposals for new liquid propulsion technology development in the future in China are presented.     

中国运载火箭地面系统发展方向研究

地面系统用于支持和保障火箭的发射与试验,对火箭的使用性能、发射能力、发射场配置及工作流程等有重要的影响。调研了国外运载火箭地面系统发展现状,总结了国外运载火箭地面系统发展趋势。从快速发射、简易发射、安全发射、自动发射和通用发射等方面提出了地面系统发展思路和主要关键技术,为我国后续运载火箭地面系统发展提供参考。     

可重复使用运载器复合材料低温贮箱应用研究

轻质高强度低温贮箱是发展可重复使用运载器（RLV）的关键技术之一。本文论证了聚合物复合材料作为低温贮箱材料的必要性和可行性,介绍了复合材料低温贮箱的研制现状,对聚合物基体和纤维选择、设计技术、复合材料的成型及其性能测试等进行了探讨,指出了复合材料低温贮箱的发展趋势,并就我国复合材料低温贮箱的发展给出了建议。     

The shuttle development and its growth potential

During the next two decades, we will establish the foundation for the 21st century's accomplishments in space. The Space Shuttle vehicle will become the cornerstone for that foundation by providing economical opportunities for space exploration and utilization.Reusability of the Shuttle vehicle is the key to its economy. The major developmental challenges encountered in the Shuttle program are typified by the complexities involved in designing the reusable propulsion and thermal protection subsystems. We successfully met such challenges and are nearing the launch of the first Shuttle orbital flight.Our immediate goal is to enter the Space Shuttle operational phase because only then will we fully understand the unique capabilities of the Shuttle. Concurrent with our effort to begin Shuttle operations are our initial efforts to expand Shuttle capabilities, extending them significantly beyond those of the current baseline system.Shuttle payload capacity and mission-duration capabilities are to increase considerably during the next decade. Just as present Shuttle performance specifications and development timetables were guided by the space program plans and forecasts of the 1960s, so will the development of long-range space programs be determined by our near-future achievements. We anticipate that the Space Shuttle will play a critical role in those achievements.