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Viewing 22051 to 22080 of 23244
1975-02-01
Technical Paper
750447
W. Fitzgerald, J.V.D. Wilson
: The presence of a metal such as calcium or zinc in a lubricant appears to inhibit the poisoning effect of phosphorus on platinum oxidising catalysts. This is a general conclusion from rig, engine and vehicle tests on lubricants with different additive components. Among the test results reported a lubricant blend with 2.5% by weight ZDDP (0 22% wt Zn) and another blend with 1.25% wt ZDDP plus enough phosphorus containing ashless anti-oxidant to double the phosphorus content of the lubricant both gave satisfactory performance in tersm of catalyst degradation.
1975-02-01
Technical Paper
750517
M. Brenckmann
The events and findings concerning public acceptance during the planning and operational phases of a downtown-to-downtown STOL demonstration service are being reviewed in this paper as a case study on public affair matters in technology innovation. The factors conducive to the successful introduction of future STOL services are more particularly dealt with, on the basis of experience to date.
1975-02-01
Technical Paper
750512
M. G. Nagati, M. G. Huff
A fatigue meter data acquisition and processing program has been set up to take advantage of the operational nature of commuter airlines, with the purpose of defining the fatigue life of an aircraft on an individual airline basis. Commuter airlines operate in a confined geographical area with its particular weather and turbulence characteristics. The result was that in most cases, a substantial increase in the aircraft's fatigue life could be justified in comparison with the one estimated by using a unified turbulence model, which was conservatively established from V-G/VGH recordings from aircraft flying all over the country.
1975-02-01
Technical Paper
750840
D. W. Tryhorn, H. L. Pullen, E. C. Grover
The paper divides into two parts. First the investigation of the noise of an unconventional design of two cycle diesel engine, including the results of applying known noise reducing features to it. Then taking one component of that engine, the scavenge blower, and re-designing it from first principles to produce a low noise machine suitable for the low noise engine. The final assembly of engine and blower demonstrated that the noise that has been regarded the characteristic of the two cycle engine is in fact that of the Roots type blower and when eliminated the noise level can be quite low. The present test bed noise level of 97/98 dBA at 1 metre shows promise of this type of engine meeting the legislative requirements of the 1980's.
1975-02-01
Technical Paper
750797
D. Anderton, V. K. Duggal
The overall effect of two methods of turbocharging a direct injection four stroke diesel engine in terms of performance, smoke, noise and gaseous emissions is described. It is shown that the effect of turbocharging is to produce a more socially acceptable engine. Matched turbocharging involving reduced compression ratios produces substantial emissions and combustion noise reductions (up to 16dB) at full load but can increase combustion noise levels considerably (8dB) at light load. Before full advantage can be taken, methods of controlling the characteristics of turbochargers to maintain short ignition delays at all conditions are required, together with reductions in engine mechanical noise levels.
1975-02-01
Technical Paper
750337
I. M. Khan, A. C. Green
This paper deals with the requirements for scheduling injection timing as a function of speed and load for high-speed light-duty diesel engines and also for larger diesel engines. A combined speed and load timing device developed for the CAV DPA pump is presented. Work on two passenger cars powered with swirl chamber diesel engines initially having standard DPA pumps and later fitted with pumps incorporating the timing scheduling device is then described and discussed. Some examples of timing scheduling requirements for larger direct injection engines are also given. It is shown that injection timing scheduling is essential to minimize gaseous and visible emissions while satisfying the noise and fuel economy aspects of engine or vehicle performance.
1975-02-01
Technical Paper
750205
Karl J. Springer, Ralph C. Stahman
Exhaust emissions from in-use diesel trucks and buses can be reduced by application of retrofits consisting of new parts and adjustments. The results of fleet test demonstrations of two retrofit kits, one for 2-stroke diesel-powered buses and the other for 4-stroke diesel trucks, are described. Except for the catalytic muffler, the components and adjustments composing the General Motors environmental improvement proposal kit for General Motors city buses were found helpful in reducing exhaust odor, smoke, and certain gaseous emissions. The turbocharger kit and adjustments marketed by Cummins Engine for its NHC 250, an in-use naturally aspirated truck engine, was likewise found to reduce visible smoke satisfactorily. The fleet test data are from three city buses operated for two years and three intercity truck tractors operated for eight months.
1975-02-01
Standard
J1099_197502
Information that provides design guidance in avoiding fatigue failures is outlined in this SAE Information Report. Of necessity, this report is brief, but it does provide a basis for approaching complex fatigue problems. Information presented here can be used in preliminary design estimates of fatigue life, the selection of materials and the analysis of service load and/or strain data. The data presented are for the "low cycle" or strain-controlled methods for predicting fatigue behavior. Note that these methods may not be appropriate for materials with internal defects, such as cast irons, which exhibit different tension and compressure stress-strain behavior.
1975-02-01
Technical Paper
750051
Kurt Obländer, Bertold Mayr
This paper discusses the Mercedes-Benz V-8 engines, their design as compared to US V-8 engines, and development concerning exhaust emission control and fuel consumption. Also covered are special problem areas, and their respective solutions which today have come to be of secondary importance, for example, the lubrication system, defoaming of the lubricant, noises generated by the lubrication system, and the adaptation of the hydraulic valve clearance adjustment to high engine speeds.
1975-02-01
Technical Paper
750174
Ronald J. Herrin
Automotive thermal reactors have obtained high conversion efficiencies on engines with very rich carburetion, but fuel economy and reactor durability have suffered. Improved mixing of exhaust gas and secondary air in the engine exhaust port was examined as a means of improving reactor efficiency at less rich engine air-fuel ratios. Three air-injection systems which span a broad range of mixing capabilities were examined. Mixing characteristics were deduced from anemometry measurements of instantaneous secondary airflow, and emission performance of each system was generalized by a test program employing four steady-state conditions. High-pressure, timed air injection provides the best mixing and the best reactor performance. Sparger (radial discharge) air injection tubes provide fair mixing and better performance than conventional open-ended air injection tubes, which exhibit poor mixing characteristics.
1975-02-01
Technical Paper
751120
Gerhard Neumann
Abstract The rapid and dramatic growth of aviation over the past several decades is a matter of history with which we are all quite familiar. Integral to that growth has been the mushrooming progress in powerplant technology which, by necessity, is the lead factor in the development of aircraft systems. This paper highlights some of the major milestones that have influenced the course of developments in gas turbine powerplants. It traces its origins in work done on turbosuperchargers, with discussion of the stimuli and shifts in requirements that resulted in various types of jet engines leading up to today's high-bypass turbofans. The natural quest to fly higher, faster and further has reached a point of relative maturity in technology so that today's efforts can now be directed more towards improvements in efficiency, reliability and ecological consciousness. The future holds new challenges.
1975-02-01
Technical Paper
750910
J. J. Mooney, J. G. Hansel, R. D. Hoyer
In contrast to motorcycles with 4-stroke engines, 2-stroke engine motorcycles produce very high hydrocarbon and carbon monoxide emissions. Compared to a 1976 automobile, such motorcycles produce as much hydrocarbon emissions as ten to twenty passenger cars. Modified automobile catalyst technology with the addition of an air pump is shown to be effective in reducing the hydrocarbon and carbon monoxide emissions by 75 - 85% after mileage accumulation of 12,000 miles; these tests are in progress and are being continued. In spite of the fact that current 2-stroke engine motorcycles run rich (no excess air) hydrocarbon emissions can be reduced by 35% and higher with aged catalyst systems without the addition of air. The mechanical durability of the catalytic systems is completely satisfactory. Present data indicate that catalyst system technology has been developed to meet proposed interim EPA emission standards for 2-stroke motorcycle engines.
1975-01-01
Standard
ARP695B
This Aerospace Recommended Practice provides design and installation criteria intended to enhance overall safety by mitigating exposure of cabin crew and passengers to risks from: a. Routine use of galley systems. b. Galley components or equipment becoming dislodged under routine or abnormal operating conditions and under survivable crash or ditching conditions. c. Malfunctions of, or defects in, a galley system or associated galley equipment. NOTE: It is not the purpose of this Aerospace Recommended Practice to specify the specific designs or design methods to be followed in the accomplishment of stated objectives.
1974-03-01
Standard
AIR1209
This Aerospace Information Report (AIR) is intended to provide information relating to the construction, calibration, and usage of parallel plate transmission lines in electromagnetic compatibility susceptibility testing.
1974-02-01
Technical Paper
740313
Paul Oppenheimer
Important new braking regulations for motor vehicles and trailers have recently been introduced by Sweden, the Economic Commission for Europe (Geneva), and the European Economic Community (Brussels). This paper describes the relevant rulemaking procedures and the international organizations which provide for industry participation. The technical content of these regulations is summarized and specific examples of difficult, interesting, or unusual demands are highlighted. Some comparisons with the appropriate United States federal standards have been included and the European method of type approval is explained against the background of self-certification in the United States. Several new European proposals for tractor/trailer compatibility, brake apportioning, and antiskid systems are reviewed to illustrate the current status of legislative progress in Europe.
1974-02-01
Technical Paper
740304
Elizabeth A. Heard
The International Organization for Standardization, Technical Committee 22, Subcommittee 13, Working Group 5 was given the task of determining which symbols should be proposed for standardization for fifteen controls, indicators and telltales. A test was devised in which three different symbols for each given control, indicator or telltale could be appraised by licensed drivers in a simulated driving situation. Data from 2593 licensed drivers from France, Germany, the United Kingdom, and the United States were obtained and statistically treated. The procedure and results are herein reported. On the basis of these results, symbols for 12 controls, indicators, and telltales were proposed as standards.
1974-02-01
Technical Paper
740231
J. W. Baxter, L. J. Lawson
This paper considers the need for improving urban transportation and the proposed air quality plans that have been recently announced by the Environmental Protection Agency for several of the more populated regional basins. The “transit diversion mandate” (the need for diversion of a considerable portion of urban travel from the automobile to public transit) is discussed. One proposed diversionary approach, the rubber-tired trolley coach, with its quiet, reliable, and pollution-free characteristics and an advanced LMSC kinetic energy flywheel which can be used to broaden considerably the capabilities of the trolley coach are described.
1974-02-01
Technical Paper
740224
Roger H. Harrison
Construction of a mass transit system is usually among the largest of civil projects, running into billions of dollars. The disruptive act of building exclusive mass transit rights-of-way through densely populated areas will further aggravate existing modes of transportation. The general case of a metropolitan area whose population is in excess of a million people is examined with regard to selection and design of a mass transportation system. Systems that can handle 100,000-200,000 passengers during morning and evening rash hours are discussed.
1974-02-01
Technical Paper
740025
Roosevelt Steptoe
The impacts of locating and operating highways and other transportation facilities in disadvantaged, minority neighborhoods are being assessed in the inquiry that this report is based upon. The major impact areas being investigated are the changes in: land use, population and residential densities, and the growth and development of minority business enterprises. This is a report of a partial inventory of conditions in the study area before the highway; it will be completed for comparison with the data to be assembled for the area after the highway. The partially complete baseline inquiry reveals that the study area has been developed partially in a very piecemeal and haphazard manner. This is evidenced by the existence of large tracts of undeveloped land, a mixture of light industrial and commercial activities with residential neighborhoods, and the fact that a high proportion of the local streets are dead-end and are poorly maintained.
1974-02-01
Technical Paper
740023
Robert H. Cannon
The U.S. Department of Transportation Program of University Research aims to focus interdisciplinary research on all phases of transportation problems. This involves the work of economists, geographers, demographers, city planners, behavioral scientists, as well as technologists. The very best minds in our universities will be needed to help us understand the complex, critical relationships between transportation and the society it serves. This paper outlines the objectives of the Program and DOT's philosophy in granting contracts to the universities. In contrast to many other programs, in this one the federal government is the sponsor of the research-the “customer” is the transportation communities. Thus, proposals involve a high degree of commitment between the universities and their local transportation communities.
1974-02-01
Technical Paper
740168
Y. Bréele
Considerable advances have been made in recent years in the field of hydrogen-air fuel cells, and plans are already being made to use such power generators for urban transportation. This is shown by a study of the possibility of equipping a vehicle of the Renault 4L type with a hydrogen-air cell. This paper describes a detailed study of such an installation. The weight of the power source is acceptable, as are the rates of acceleration. A speed of 80 km/h (50 mph) can be sustained continuously, and an autonomy of between 230 and 560 km (143 and 348 miles) can be attained depending upon the speed of the vehicle, with an effective load of 340 kg (750 lb). Two important obstacles (power source and use of hydrogen) are in the process of being solved by using inexpensive materials and by storing hydrogen by means of hydrides.
1974-02-01
Technical Paper
740617
Roger H. Hemion
The feasibility of approving the use of a rectangular shaped, sealed-beam headlamp as an alternative to round headlamps is discussed in terms of economics, service and maintainability, vehicle design, and styling. A conclusion of primary interest is reached, that design as well as performance standardization is in the interest of the buying public, under certain conditions, and proliferation of designs without compensatory gain should be avoided.
1974-02-01
Technical Paper
740544
William H. Close
This paper analyzes the rationale behind the federal regulation of interstate motor carrier noise. At highway speeds, tire noise is frequently predominant. At low speeds, engine-related noise is predominant. The effects of both these noise sources are considered. The question of enforceability of the regulation is also discussed.
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