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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 397 records · Page 22
All sourcesNASA NTRSDOE OSTI
NASA NTRS1992

Arrow 227: Air transport system design simulation

The Arrow 227 is a student-designed commercial transport for use in a overnight package delivery network. The major goal of the concept was to provide the delivery service with the greatest potential return on investment. The design objectives of the Arrow 227 were based on three parameters; production cost, payload weight, and aerodynamic efficiency. Low production cost helps to reduce initial investment. Increased payload weight allows for a decrease in flight cycles and, therefore, less fuel consumption than an aircraft carrying less payload weight and requiring more flight cycles. In addition, fewer flight cycles will allow a fleet to last longer. Finally, increased aerodynamic efficiency in the form of high L/D will decrease fuel consumption.

Bontempi, Michael↗
NASA NTRS2012

Approach to an Affordable and Sustainable Space Transportation System

This paper describes an approach and a general procedure for creating space transportation architectural concepts that are at once affordable and sustainable. Previous papers by the authors and other members of the Space Propulsion Synergy Team (SPST) focused on a functional system breakdown structure for an architecture and definition of high-payoff design techniques with a technology integration strategy. This paper follows up by using a structured process that derives architectural solutions focused on achieving life cycle affordability and sustainability. Further, the paper includes an example concept that integrates key design techniques discussed in previous papers. !

McCleskey, Caey M.↗
NASA NTRS1982

Structural design of integral tankage for advanced space transportation systems

Fully reusable launch vehicle concepts being studied for post-Shuttle era transports present major challenges for the structural design of large propellant tankage. The dominant structural elements are internal tankage for both cryogenic and non-cryogenic propellants which must operate in a broad range of thermal environments while meeting requirements for low weight and reusability. Several approaches to integral tank design are discussed and an analysis of a hot structure honeycomb sandwich tank for a circular body vehicle is presented.

Macconochie, I. O.↗
NASA NTRS1972

Technology for design of transport aircraft. Lecture notes for MIT courses: Seminar 1.61 freshman seminar in air transportation and graduate course 1.201, transportation systems analysis

The design parameters which determine cruise performance for a conventional subsonic jet transport are discussed. It is assumed that the aircraft burns climb fuel to reach cruising altitude and that aeronautical technology determines the ability to carry a given payload at cruising altitude. It is shown that different sizes of transport aircraft are needed to provide the cost optimal vehicle for different given payload-range objectives.

Simpson, R. W.↗
NASA NTRS2004

A Comparison of Transportation Systems for Human Missions to Mars

There are many ways to send humans to Mars. Credible technical reports can be traced to the 1950's. More recently, NASA has funded major studies that depict a broad variety of trajectories, technologies, stay times, and costs. Much of this data is still valid with direct application to today's exploration planning. This paper presents results comparing these studies with particular emphasis on the in-space transportation aspects of the mission. Specifically, comparisons are made on propulsion systems used for getting the crew and mission equipment from Earth orbit to Mars orbit, descending and ascending from the surface, and returning to Earth orbit. Areas of comparison for each of these phases include crew size, mission mass, propellant mass, delta v, specific impulse, transit time, surface stay time, aero-braking, and others. Data is analyzed to demonstrate either strong trends toward particular technologies or diverging solutions.

Bipropellants↗
NASA NTRS1994

Fault tolerant computer control for a Maglev transportation system

Magnetically levitated (Maglev) vehicles operating on dedicated guideways at speeds of 500 km/hr are an emerging transportation alternative to short-haul air and high-speed rail. They have the potential to offer a service significantly more dependable than air and with less operating cost than both air and high-speed rail. Maglev transportation derives these benefits by using magnetic forces to suspend a vehicle 8 to 200 mm above the guideway. Magnetic forces are also used for propulsion and guidance. The combination of high speed, short headways, stringent ride quality requirements, and a distributed offboard propulsion system necessitates high levels of automation for the Maglev control and operation. Very high levels of safety and availability will be required for the Maglev control system. This paper describes the mission scenario, functional requirements, and dependability and performance requirements of the Maglev command, control, and communications system. A distributed hierarchical architecture consisting of vehicle on-board computers, wayside zone computers, a central computer facility, and communication links between these entities was synthesized to meet the functional and dependability requirements on the maglev. Two variations of the basic architecture are described: the Smart Vehicle Architecture (SVA) and the Zone Control Architecture (ZCA). Preliminary dependability modeling results are also presented.

Lala, Jaynarayan H.↗
NASA NTRS1976

Technology assessment of future intercity passenger transportation systems. Volume 6: Impact assessment

Consequences that might occur if certain technological developments take place in intercity transportation are described. These consequences are broad ranging, and include economic, environmental, social, institutional, energy-related, and transportation service implications. The possible consequences are traced through direct (primary) impacts to indirect (secondary, tertiary, etc.) impacts. Chains of consequences are traced, reaching as far beyond the original transportation cause as is necessary to identify all impacts felt to be influenced significantly by the technological development considered.

Source record↗
NASA NTRS1979

Pricing of NASA Space Shuttle transportation system cargo

A two-part pricing policy is investigated as the most feasible method of pricing the transportation services to be provided by NASA's SSTS. Engineering cost estimates and a deterministic operating cost model generate a data base and develop a procedure for pricing the services of the SSTS. It is expected that the SSTS will have a monopoly on space material processing in areas of crystal growth, glass processing, metallurgical space applications, and biomedical processes using electrophoresis which will require efficient pricing. Pricing problems, the SSTS operating costs based on orbit elevation, number of launch sites, and number of flights, capital costs of the SSTS, research and development costs, allocation of joint transportation costs of the SSTS to a particular space processing activity, and rates for the SSTS are discussed. It is concluded that joint costs for commercial cargoes carried in the SSTS can be most usefully handled by making cost allocations based on proportionate capacity utilization.

Hale, C. W.↗
NASA NTRS1981

Thermal management of instruments on space platforms using a high capacity two-phase heat transport system

A system utilizing a pumped, two-phase single component working fluid for heat exchange and transport services necessary to meet the temperature control requirements of typical orbiting instrument payloads on space platforms is described. The design characteristics of the system is presented, together with a presentation of a laboratory apparatus for demonstration of proof of concept. Results indicate that the pumped two-phase design concept can meet a wide range of thermal performance requirements with the only penalty being the requirement for a small liquid pump.

Ollendorf, S.↗
NASA NTRS2008

Engineering America's Current and Future Space Transportation Systems: 50 Years of Systems Engineering Innovation for Sustainable Exploration

Over the past 50 years, the National Aeronautics and Space Administration (NASA) has delivered space transportation solutions for America's complex missions, ranging from scientific payloads that expand knowledge, such as the Hubble Space Telescope, to astronauts and lunar rovers destined for voyages to the Moon. Currently, the venerable Space Shuttle, which has been in service since 1981, provides the United States' (U.S.) capability for both crew and heavy cargo to low-Earth orbit to' construct the International Space Station, before the Shuttle is retired in 2010. In the next decade, NASA will replace this system with a duo of launch vehicles: the Ares I Crew Launch Vehicle and the Ares V Cargo Launch Vehicle (Figure 1). The goals for this new system include increased safety and reliability coupled with lower operations costs that promote sustainable space exploration for decades to come. The Ares I will loft the Orion Crew Exploration Vehicle, while the heavy-lift Ares V will carry the Altair Lunar Lander and the equipment and supplies needed to construct a lunar outpost for a new generation of human and robotic space pioneers. This paper will provide details of the in-house systems engineering and vehicle integration work now being performed for the Ares I and planned for the Ares V. It will give an overview of the Ares I system-level test activities, such as the ground vibration testing that will be conducted in the Marshall Center's Dynamic Test Stand to verify the integrated vehicle stack's structural integrity and to validate computer modeling and simulation (Figure 2), as well as the main propulsion test article analysis to be conducted in the Static Test Stand. These activities also will help prove and refine mission concepts of operation, while supporting the spectrum of design and development work being performed by Marshall's Engineering Directorate, ranging from launch vehicles and lunar rovers to scientific spacecraft and associated experiments. Ultimately, fielding a robust space transportation solution that will carry international explorers and essential payloads will pave the way for a new century of scientific discovery beyond planet Earth.

Dmbacher, Daniel L.↗
NASA NTRS1972

Study of short haul high-density V/STOL transportation systems, volume 1

The relative advantages of STOL aircraft concepts were examined by simulating the operations of a short haul high-density intercity STOL system set in two arenas, the California corridor and the Chicago-Detroit-Cleveland triangle, during the 1980 time period. The study was constrained to the use of three aircraft concepts designated as the deflected slipstream turboprop, externally blown flap, and augmentor wing turbofan configurations. The projected demographic, economic, travel demand, and travel characteristics of the representative arenas were identified. The STOL airline operating scenarios were then formulated and through the use of the aerospace modal split simulation program, the traveler modal choices involving alternative STOL concepts were estimated in the context of the total transportation environment for 1980. System combinations that presented the best potential for economic return and traveler acceptance were then identified for each STOL concept.

Solomon, H. L.↗
NASA NTRS1976

Aeromaneuvering Orbit Transfer Vehicles for the space transport system

Alternatives to all-propulsive manned Orbit Transfer Vehicles (OTV) are presented that utilize aeromaneuvering in combination with propulsive maneuvering. A summary of the results of feasibility and concept definition studies is induced along with a discussion of the advantages and disadvantages of aeromaneuvering as compared with all-propulsive vehicles. Manned aeromaneuvering OTV concepts are described, including the Aeromaneuvering Orbit-to-Orbit Shuttle (AMOOS) for future orbital transportation and the Aeromaneuvering Recovery System (AMRS) for emergency recovery of crewmen from high-altitude orbits. Data are provided regarding aeromaneuvering OTV configurations, performance, systems, tradeoffs, mission applications, and major design parameters, such as dynamic pressure, heating rates, and guidance.

Hethcoat, J. P.↗
NASA NTRS1998

Highly Reusable Space Transportation System Concept Evaluation (The Argus Launch Vehicle)

This paper summarizes the results of a conceptual design study that was performed in support of NASA's recent Highly Reusable Space Transportation study. The Argus concept uses a Maglifter magnetic-levitation sled launch assist system to accelerate it to a takeoff ground speed of 800 fps on its way to delivering a payload of 20,000 lb. to low earth orbit. Main propulsion is provided by two supercharged ejector rocket engines. The vehicle is autonomous and is fully reusable. A conceptual design exercise determined the vehicle gross weight to be approximately 597,250 lb. and the dry weight to be 75,500 lb. Aggressive weight and operations cost assumptions were used throughout the design process consistent with a second-generation reusable system that might be deployed in 10-15 years. Drawings, geometry, and weight of the concept are included. Preliminary development, production, and operations costs along with a business scenario assuming a price-elastic payload market are also included. A fleet of three Argus launch vehicles flying a total of 149 flights per year is shown to have a financial internal rate of return of 28%. At $169/lb., the recurring cost of Argus is shown to meet the study goal of $100/lb.-$200/lb., but optimum market price results in only a factor of two to five reduction compared to today's launch systems.

Olds, John R.↗
NASA NTRS1989

First incremental buy for Increment 2 of the Space Transportation System (STS)

Thiokol manufactured and delivered 9 flight motors to KSC on schedule. All test flights were successful. All spent SRMs were recovered. Design, development, manufacture, and delivery of required transportation, handling, and checkout equipment to MSFC and to KSC were completed on schedule. All items of data required by DPD 400 were prepared and delivered as directed. In the system requirements and analysis area, the point of departure from Buy 1 to the operational phase was developed in significant detail with a complete set of transition documentation available. The documentation prepared during the Buy 1 program was maintained and updated where required. The following flight support activities should be continued through other production programs: as-built materials usage tracking on all flight hardware; mass properties reporting for all flight hardware until sample size is large enough to verify that the weight limit requirements were met; ballistic predictions and postflight performance assessments for all production flights; and recovered SRM hardware inspection and anomaly identification. In the safety, reliability, and quality assurance area, activities accomplished were assurance oriented in nature and specifically formulated to prevent problems and hardware failures. The flight program to date has adequately demonstrated the success of this assurance approach. The attention focused on details of design, analysis, manufacture, and inspection to assure the production of high-quality hardware has resulted in the absence of flight failures. The few anomalies which did occur were evaluated, design or manufacturing changes incorporated, and corrective actions taken to preclude recurrence.

Source record↗
NASA NTRS1992

Utilization of space resources in the space transportation system

Utilization of space resources (i.e., raw materials obtained from nonterrestrial sources) has often been cited as a prerequisite for large-scale industrialization and habitation of space. While transportation of extremely large quantities of material from Earth would be costly and potentially destructive to our environment, vast quantities of usable resources might be derived from the Moon, the asteroids, and other celestial objects in a cost-effective and environmentally benign manner. The primary purpose of the parametric cost model developed as part of this study is to identify the factors that have the greatest influence on the economics of space resource utilization. In the near term, this information can be used to devise strategies for technology development so that capabilities developed will produce cost-effective results.

Simon, Michael C.↗
NASA NTRS2002

Miniature Heat Transport System for Spacecraft Thermal Control

Loop heat pipes (LHP) are efficient devices for heat transfer and use the basic principle of a closed evaporation-condensation cycle. The advantage of using a loop heat pipe over other conventional methods is that large quantities of heat can be transported through a small cross-sectional area over a considerable distance with no additional power input to the system. By using LHPs, it seems possible to meet the growing demand for high-power cooling devices. Although they are somewhat similar to conventional heat pipes, LHPs have a whole set of unique properties, such as low pressure drops and flexible lines between condenser and evaporator, that make them rather promising. LHPs are capable of providing a means of transporting heat over long distances with no input power other than the heat being transported because of the specially designed evaporator and the separation of liquid and vapor lines. For LHP design and fabrication, preliminary analysis on the basis of dimensionless criteria is necessary because of certain complicated phenomena that take place in the heat pipe. Modeling the performance of the LHP and miniaturizing its size are tasks and objectives of current research. In the course of h s work, the LHP and its components, including the evaporator (the most critical and complex part of the LHP), were modeled with the corresponding dimensionless groups also being investigated. Next, analysis of heat and mass transfer processes in the LHP, selection of the most weighted criteria from known dimensionless groups (thermal-fluid sciences), heat transfer rate limits, (heat pipe theory), and experimental ratios which are unique to a given heat pipe class are discussed. In the third part of the report, two-phase flow heat and mass transfer performances inside the LHP condenser are analyzed and calculated for Earth-normal gravity and microgravity conditions. On the basis of recent models and experimental databanks, an analysis for condensing two-phase flow regimes, pressure gradients, and local heat transfer coefficients using ammonia, propylene, and R134, are carried out.

Ochterbeck, Jay M.↗
NASA NTRS1991

CFM technology needs for future space transportation systems

Several technological capabilities must be developed to realize the vision of the Space Exploration Initiative (SEI). Cryogenic fluid management (CFM) is one technology area common to virtually every space transportation propulsion concept envisioned. The physics of storage, supply, transfer, and handling of subcritical cryogenic fluids in the reduced gravity environment of space present fundamental challenges. The CFM state of the art relative to future mission requirements is reviewed and associated technology challenges are outlined.

Hastings, L. J.↗