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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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Overall and specific information about the technological characteristics of present, future, and possible future technological forms of transportation modes are presented.
Four background scenarios that relate to alternative states of society in the next 25 to 50 years are described. The scenarios were developed for use in analyzing and evaluating alternative future intercity transportation technologies. The scenarios are based, in part, on discussions contained in the issue papers and, in part, on separate analysis of social and economic trends considered relevant for the evolution of intercity transportation.
Proceedings of a workshop conducted to identify and debate issues and impacts related to future transporation alternatives are presented. Results of the technology assessment of intercity transportation are reviewed.
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.
Papers are presented dealing with the development of aircraft seats with the minimum fire risk. Criteria examined include: flame spread, heat release, and smoke and/or toxic fumes. Materials and performance specifications of all seat material options are provided.
Seat comfort and safety research since the early part of the century is reviewed. The approach blends empirical and theoretical human factors and technical knowledge of seated humans under static and dynamic conditions experienced on commercial aircraft.
This paper considers the effect of noise on conversation between two persons seated in a close, side-by-side position such as in a small aircraft. Twelve pairs of subjects were required to converse while being exposed to noises of various levels and spectra similar to those currently found in general aviation aircraft. After a period of noise exposure, subjects rated the disruptive effect of the noise on conversation and judged the acceptability of the noise. Subjective estimates of the maximum times for pleasant conversation in the noises were also obtained.
The procurement and testing of a wide range of candidate materials is reported. Improved fire resistant nonmetallic materials were subjected to tests to evaluate their thermal characteristics, such as burn, smoke generation, heat release rate and toxicity. In addition, candidate materials were evaluated for mechanical, physical and aesthetic properties. Other properties considered included safety, comfort, durability and maintainability. The fiscal year 1977 and the projected 1980 cost data were obtained for aircraft seat materials.
The framework for a model of travel demand which will be useful in predicting the total market for air travel between two cities is discussed. Variables to be used in determining the need for air transportation where none currently exists and the effect of changes in system characteristics on attracting latent demand are identified. Existing models are examined in order to provide insight into their strong points and shortcomings. Much of the existing behavioral research in travel demand is incorporated to allow the inclusion of non-economic factors, such as convenience. The model developed is characterized as a market segmentation model. This is a consequence of the strengths of disaggregation and its natural evolution to a usable aggregate formulation. The need for this approach both pedagogically and mathematically is discussed.
Previous intercity travel demand models in terms of their ability to predict air travel in a useful way and the need for disaggregation in the approach to demand modelling are evaluated. The viability of incorporating non-conventional factors (i.e. non-econometric, such as time and cost) in travel demand forecasting models are determined. The investigation of existing models is carried out in order to provide insight into their strong points and shortcomings. The model is characterized as a market segmentation model. This is a consequence of the strengths of disaggregation and its natural evolution to a usable aggregate formulation. The need for this approach both pedagogically and mathematically is discussed. In addition this volume contains two appendices which should prove useful to the non-specialist in the area.
The essential elements of the problem and of approaches to improved fire resistance in aircraft seats are reviewed. The performance requirements and availability of materials, delay in the ignition of upholstery fabric by a small source are considered a realistic objective. Results of experimental studies on the thermal response of fabrics and fabric/foam combinations suggest significant conclusions regarding: (1) the ignition behavior of a commercial 90/10 wool/nylon upholstery fabric relative to fabrics made from thermally stable polymers; (2) the role of the foam backing; (3) the behavior of seams. These results, coupled with data from other sources, also confirm the importance of materials' interactions in multicomponent assemblies, and the need for system testing prior to materials' selection. The use of an interlinear or thermal barrier between upholstery fabric and foam is a promising and viable approach to improved fire resistance of the seat assembly, but experimental evaluation of specific combinations of materials or systems is an essential part of the selection process.
Fire tests are reported of improved materials in multilayered combinations representative of cushion configurations. Tests were conducted to determine their thermal, smoke, and fire resistance characteristics. Additionally, a source fire consisting of one and one-half pounds of newspaper in a tented configuration was developed. Finally, a preliminary seat specification was written based upon materials data and general seat design criteria.
Several demand models for short haul air travel are proposed and calibrated on pooled data. The models are designed to predict demand and analyze some of the motivating phenomena behind demand generation. In particular, an attempt is made to include the effects of competing modes and of alternate destinations. The results support three conclusions: (1) the auto mode is the air mode's major competitor; (2) trip time is an overriding factor in intermodal competition, with air fare at its present level appearing unimportant to the typical short haul air traveler; and (3) distance appears to underly several demand generating phenomena, and therefore, must be considered very carefully to any intercity demand model. It may be the cause of the wide range of fare elasticities reported by researchers over the past 15 years. A behavioral demand model is proposed and calibrated. It combines the travel generating effects of income and population, the effects of modal split, the sensitivity of travel to price and time, and the effect of alternative destinations satisfying the trip purpose.
The enabling legislation of 1976 for improvement of service in the Northeast corridor (NEC) requires a schedule of 2 h 40 min between Washington and New York City by 1981 and 3 h 40 min between NYC and Boston, when the electrification is completed. Various options of the NEC operation that may satisfy the legislation were investigated, particularly in terms of travel time and energy consumption. NEC operations were compared with overseas systems and practices. The emerging new technology of AC traction was also evaluated.
The three most promising vehicle use patterns (missions) for the near term electric hybrid vehicle were found to be all-purpose city driving, commuting, and family and civic business. The mission selection process was based principally on an analysis of the travel patterns found in the Nationwide Transportation Survey and on the Los Angeles and Washington, D.C. origin-destination studies data. Travel patterns in turn were converted to fuel requirements for 1985 conventional and hybrid cars. By this means, the potential fuel savings for each mission were estimated, and preliminary design requirements for hybrid vehicles were derived.
Results of tradeoff studies are presented in summary form. Various aspects of the overall vehicle design discussed include selection of the base vehicle, the battery pack configuration, structural modifications, occupant protection, vehicle dynamics, and aerodynamics. The drivetrain design and integration, power conditioning unit, battery subsystem, control system, environmental system are described. Specifications, weight breakdown, and energy consumption measures, and advanced technology components are included.
Missions for hybrid vehicles that promise to yield high petroleum impact were identified and a preliminary design, was developed that satisfies the mission requirements and performance specifications. Technologies that are critical to successful vehicle design, development and fabrication were determined. Trade-off studies to maximize fuel savings were used to develop initial design specifications of the near term hybrid vehicle. Various designs were "driven" through detailed computer simulations which calculate the petroleum consumption in standard driving cycles, the petroleum and electricity consumptions over the specified missions, and the vehicle's life cycle costs over a 10 year vehicle lifetime. Particular attention was given to the selection of the electric motor, heat engine, drivetrain, battery pack and control system. The preliminary design reflects a modified current compact car powered by a currently available turbocharged diesel engine and a 24 kW (peak) compound dc electric motor.
Applicable data was categorized and processed according to vehicle usage and trip parameters with consideration of payload (cargo, people, size) and driving cycles. A mission that maximizes the fuel potential savings for the total 1985 vehicle fleet was selected. Mission requirements that have a bearing on conventional and hybrid vehicle performance and characteristics were identified and formulated and a reference ICE vehicle was selected that meets or exceeds all requirements while maintaining within applicable constraints. Specifications for vehicle performance were established based on mission requirements, mission related vehicle characteristics, and fuel consumption.