Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “automobiles”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 235 records · Page 13

Sensitivity of a critical tracking task to alcohol impairment

A first order critical tracking task is evaluated for its potential to discriminate between sober and intoxicated performances. Mean differences between predrink and postdrink performances as a function of BAC are analyzed. Quantification of the results shows that intoxicated failure rates of 50% for blood alcohol concentrations (BACs) at or above 0.1%, and 75% for BACs at or above 0.14%, can be attained with no sober failure rates. A high initial rate of learning is observed, perhaps due to the very nature of the task whereby the operator is always pushed to his limit, and the scores approach a stable asymptote after approximately 50 trials. Finally, the implementation of the task as an ignition interlock system in the automobile environment is discussed. It is pointed out that lower critical performance limits are anticipated for the mechanized automotive units because of the introduction of larger hardware and neuromuscular lags. Whether such degradation in performance would reduce the effectiveness of the device or not will be determined in a continuing program involving a broader based sample of the driving population and performance correlations with both BACs and driving proficiency.

Tennant, J. A.↗

Experimentally-determined external heat loss of automotive gas turbine engine

An external heat balance was conducted on a 150 HP two-shaft automotive gas turbine engine. The engine was enclosed in a calorimeter box and the temperature change of cooling air passing through the box was measured. Cooling airflow ranges of 1.6 to 2.1 lb-per-second and 0.8 to 1.1 lb-per-second were used. The engine housing heat loss increased as the cooling airflow through the calorimeter box was increased, as would be the case in a moving automobile. The heat balance between the total energy input and the sum of shaft power output and various losses compared within 30 percent at engine idle speeds and within 7 percent at full power.

Meng, P. R.↗

A compressor designed for the energy research and development agency automotive gas turbine program

A centrifugal compressor was designed for a gas turbine powered automobile as part of the Energy Research and Development Agency program to demonstrate emissions characteristics that meet 1978 standards with fuel economy and acceleration which are competitive with conventionally powered vehicles. A backswept impeller was designed for the compressor in order to attain the efficiency goal range required for the objectives of this program. Details of the design and method of flow analysis of the compressor are presented.

Galvas, M. R.↗

High power laser apparatus and system

A high-power, continuous-wave laser was designed for use in power transmission and energy-collecting systems, and for producing incoherent light for pumping a laser material. The laser has a high repetitive pulsing rate per unit time, resulting in a high-power density beam. The laser is composed of xenon flash tubes powered by fast-charging capacitors flashed in succession by a high-speed motor connected to an automobile-type distributor.

Evans, J. C., Jr.↗

NASTRAN modeling and analysis of rigid and flexible walled acoustic cavities

The acoustic slot elements, CSLOTi, are applied to analyze two-dimensional enclosures with fixed or moving boundaries. The capability utilized to compute (a) the acoustic natural modes and frequencies of a rigid walled enclosure and (b) the sound pressure at any point inside an enclosure when the surrounding walls are forced to vibrate. Applications to an automobile passenger compartment illustrate the technique. The axisymmetric fluid elements, CFLUIDi, are used in conjunction with a suitable choice of symmetry planes and a model of the surrounding structure to approximate a two-dimensional enclosure with flexible walls. The enclosure walls are modeled using finite elements or structural modes. Illustrative examples include a comparison of rectangular cavity modes with those calculated using the acoustic slot element and the free vibration modes of two enclosures coupled through a flexible rectangular panel.

Wolf, J. A., Jr.↗

Eleventh Annual Conference on Manual Control

This volume contains a compilation of written versions of papers presented at the Eleventh Annual Conference on Manual Control in a meeting held at NASA-Ames Research Center, May 21-23, 1975. Five main topics were discussed during this three-day conference. These were covered in sessions on Concurrent Tasks, Physiological Systems, Controls and Displays, Performance/Workload Evaluation, and System Identification. Forty-nine papers are included with presentations on results of analytical studies to develop and evaluate human operator models for a range of control task, vehicle dynamics and display situations; results of tests of physiological control systems and applications to medical problems; and on results of simulator and flight tests to determine display, control and dynamics effects on operator performance and workload for aircraft, automobile and remote control systems.

Source record↗

Bringing space technology down to earth

The direct transfer of space technology to terrestial applications is demonstrated by the use of fuel cells to augment existing electric power-generation facilities. The role of NASA's Technology Utilization Program is discussed in regard to indirect transfer of technology. The Tech Brief program for identifying and reporting innovations, the regional dissemination centers, and the Applications Teams working with other government agencies and the medical community are described. Projects discussed include the development of a lightweight breathing apparatus for firemen, a practical method for separating nonferrous metals from automobile scrap, and a rechargeable heart pacemaker.

Gray, E. Z.↗

Flame-resistant elastomeric polymers

Family of polymer formulations, which has limiting oxygen indices from 50 to 100, can be extruded through dies to produce elastic fibers, compression molded, dissolved in solvents as required for coatings, and calendered to produce film and embossed sheeting. Applications include upholstery, paint products, automobile products, and coated fabrics.

Howarth, J. T.↗

Low-onset-rate energy absorber

Device controls deceleration rates without amplifying system loads. It dissipates energy of motion through friction heat and is 22 times more efficient than automobile brakes.

Keathley, W. H.↗

Example of input-output analysis

The thirty sectors included in the ECASTAR energy input-output model were listed. Five of these belong to energy producing sectors, fifteen to manufacturing industries, two to residential and commercial sectors, and eight to service industries. The model is capable of tracing impacts of an action in three dimensions: dollars, BTU's of energy, and labor. Four conservation actions considered were listed and then discussed separately, dealing with the following areas: increase in fuel efficiency, reduction in fuel used by the transportation and warehousing group, manufacturing of smaller automobiles, and a communications/transportation trade-off.

Source record↗

Three strategies for conservation

The three strategies considered as energy conservation oriented were given: national energy conservation, electrification, and diversification. The first one applies to the near term period (now-1985), the second one to the mid term (1985-2000), and the third one to the far term (2000- ). The rest of this section was focussed on the near term period. The following proposed actions were considered: (1) roll back the price of newly discovered oil, (2) force conversion of many power plants from gas and oil to coal, (3) freeze gasoline production for three years at 1972 levels, (4) mandate automobile mileage requirements, (5) require industry to improve energy efficiency, and (6) require manufacture of household appliances with greater efficiency. Each of these six actions was described and discussed in more detail.

Source record↗

Economy of flight at supersonic speeds

Prandtl's theory is used to determine the airflow over bodies and wings adapted to supersonic flight. By making use of these results, and by incorporating in them an allowance for the probable skin friction, some estimates of expected lift-drag ratios are made for various flight speeds with the best configuration. At each speed a slender body and wings having the best angle of sweepback are considered. For the range of supersonic speeds shown an airplane of normal density and loading would be required to operate at an altitude of the order of 60,000 feet. The limiting value of 1-1/2 times the speed of sound corresponds to a flight speed of 1000 miles per hour. At this speed about 1.5 miles per gallon of fuel are expected. It is interesting to note that this value corresponds to a value of more than 15 miles per gallon when the weight is reduced to correspond to that of an ordinary automobile.

Jones, R. T.↗

National energy conservation

A set of energy conservation actions that cut across all sectors of the economy were analyzed so that all actions under consideration be analyzed systematically and as a whole. The actions considered were as follows: (1) roll back the price of newly discovered oil, (2) freeze gasoline production for 3 years at 1972 levels, (3) mandate automobile mileage improvements, (4) require industry to improve energy efficiency, (5) require manufacture of household appliances with greater efficiency, (6) force conversion of many power plants from gas and oil to coal. The results showed that considerable gas and oil would be saved by forcing switches to coal. However, the large scale switch to coal was shown to require greatly increased outputs from many other industries that in turn require more energy. It was estimated that nearly 2.5 quads of additional coal were needed to produce these additional requirements. Also, the indirect requirements would create more jobs.

Source record↗

The requirements for batteries for electric vehicles

Analysis of automobile use patterns shows that the battery requirements for an urban car can be met by mid-term battery technology. The far-term technology potentially offers greater range but does not proportionately increase the usefulness of the vehicle. This suggests that emphasis should be shifted toward more modest energy density goals, if such a shift would ease technical problems and allow the use of lower cost materials and construction methods. A technology diffusion model indicates that the impact of the mid-term batteries by the year 2000 would be greater than that of the far-term batteries because of their earlier introduction and nearly equal market potential. From the standpoint of maximizing both the cumulative impact and the benefits derived in the year 2000, however, a strategy of early introduction of near-term and mid-term cars followed by the far-term vehicle would produce the optimum results.

Schwartz, H. J.↗

Applications of the Ultrasonic Serial Number Restoration Technique to Guns and Typical Stolen Articles

An ultrasonic cavitation method for restoring obliterated serial numbers has been further explored by application to articles involved in police cases. The method was applied successfully to gun parts. In one case portions of numbers were restored after prior failure by other laboratories using chemical etching techniques. The ultrasonic method was not successful on a heavily obliterated and restamped automobile engine block, but it was partially successful on a motorcycle gear-case housing. Additional studies were made on the effect of a larger diameter ultrasonic probe, and on the method's ability to restore numbers obliterated by peening.

Young, S. G.↗

A model study of the impact of emission control strategies on Los Angeles air quality

A generalized cell model is developed for the calculation of city-wide averages of photochemical smog components in Los Angeles. This model takes into account the effects of variations with time and within the city of the source strengths, the wind field, and the mixing depth. The effect of the influx of background pollution from outside the modeled volume is also included. Several control strategies for reducing automobile emissions are then introduced into the model, and their impact on predicted pollutant levels, particularly those of O3, are investigated.

Hameed, S.↗

A two-dimensional model for the transport of pollutants in an urban basin

The distribution of an inert chemical species, carbon monoxide (CO), emitted mainly from automobile exhaust is investigated. The transport model, in analogy with the shallow water theory in fluid dynamics, considers variation of all physical quantities in the horizontal direction below the temperature inversion layer. Pollutants are found to be carried primarily by the wind; turbulent diffusion in a normal day plays only a minor role. The concentration of CO predicted by the present model for the entire Los Angeles basin is compared with observed data at nine stations. Accuracy of four different numerical schemes, the effect of turbulent diffusivity, and the source strengths are examined.

Liu, C. Y.↗

Rechargeable nickel-zinc batteries

Device proves superiority in having two and one half to three times the energy content of popular lead-zinc or nickel-cadmium batteries. Application to electric utility vehicles improved acceleration rate and nearly doubled driving range between rechargings. Unit contributes substantially toward realization of practical urban electrical automobiles.

Soltis, D. G.↗