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1975-02-01
Technical Paper
750930
James E. A. John
This paper discusses lean burn engine concepts for meeting emission standards features versus the use of an oxidizing catalytic converter for HC and CO control. Purely theoretical considerations indicate that thermal efficiency and therefore fuel economy should be improved by lean operation. Whether this system will be used is dependent on the Federally regulated auto emissions standards.
1975-02-01
Technical Paper
750931
Naeim A. Henein
An evaluation has been made of the use of the diesel as an alternative engine in passenger cars. This includes the technological feasibility for meeting the different emission standards and the techniques for emission control. The emissions studied include both the presently regulated species--hydrocarbons, carbon monoxide, and nitrogen oxides--and the following nonregulated emissions: aldehydes, ammonia, smoke and particulates, polynuclear aromatics, and sulfur compounds. A comparison has been made between the emissions, performance and economy of currently produced diesel powered cars and gasoline powered cars. Other cars which are being developed and powered by the stratified charge, Wankel, and the gas turbine engines are also included in the comparison. Intrinsic problem areas in the diesel engine that need further research are also identified and discussed.
1975-02-01
Technical Paper
750927
W. Moore, J. F. Stara, D. Hysell, M. Malanchuk, J. Burkart, R. Hinners
This paper presents data, from laboratory animals, on the toxicity and metabolic fate of the fuel additive methylcyclopentadienyl manganese tricarbonyl (MMT) and the biological effects following exposure to automotive exhaust emissions generated from an engine system which was run on a fuel containing MMT. The Environmental Toxicology Research Laboratory has been interested in MMT because of the potential widespread use of this additive as a replacement for tetraethyl lead as an octane improver.
1975-02-01
Technical Paper
750954
Craig Marks, George Niepoth
Car design factors which affect fuel economy include body size and shape, vehicle weight, engine size and power train design. Computer simulation results are presented to illustrate some of the basic interactions which occur among these parameters. Exhaust emission standards and other practical constraints limit the quantitative usefulness of such parameter variation studies. The fundamental relationships between engine efficiency and exhaust emissions are reviewed. It is concluded that emission constraints are important and can limit the effectiveness of some design changes to improve fuel economy. With present technology, it can be shown that stringent exhaust emission standards will reduce fuel economy more than it can be improved by car design changes which do not seriously degrade many customer perceived values such as useful capacity, driveability and acceleration capability.
1975-02-01
Technical Paper
750901
Gordon J. Kennedy, John T. White, Karl J. Springer, Melvin N. Ingalls
This is a summary compilation and analysis of exhaust-emission results and operating parameters from forty-five heavy-duty gasoline and diesel-powered vehicles tested over a 7.24-mile road course known as the San Antonio Road Route (SARR); and, for correlative purposes, on a chassis dynamometer.(2) Exhaust samples were collected and analyzed using the Constant Volume Sampler (CVS) technique similar to that used in emission testing of light-duty vehicles. On the road course, all equipment and instrumentation were located on the vehicle while electrical power was supplied by a trailer-mounted generator. In addition to exhaust emissions, operating parameters such as vehicle speed, engine speed, manifold vacuum, and transmission gear were simultaneously measured and recorded on magnetic tape. The forty-five vehicles tested represent various model years, GVW ratings, and engine types and sizes.
1975-02-01
Technical Paper
750900
Loren G. Pless
To meet exhaust emission standards, nearly all 1975 model U. S. passenger cars use catalytic converters in conjunction with unleaded gasoline. While it has been established that lead and phosphorus from gasoline are deleterious to catalyst performance, much less is known about any similar effect of elements normally present in conventional engine oils. In addition, the ability to protect engines from excessive deposits and wear is essentially unproved for engine oils in which the phosphorus and metals contents have been either reduced (low ash oils) or eliminated (ashless oils). To obtain catalyst and engine performance information on such oils, tests were run using 95, 1972-1973 model passenger cars, operated with unleaded gasoline in several types of service. Forty cars were equipped with 1975 production-prototype underfloor catalytic converters containing pelleted oxidation catalysts.
1975-02-01
Technical Paper
750908
Katsuhiko Tsuchiya, Seiji Hirano
This paper discusses the results of studies of the exhaust HC emission of 2-stroke engines for motorcycles. The major factor producing HC emissions from 2-stroke engines is the short circuiting of fresh charge. Therefore, we made a study of the relation between the delivery ratio and the trapping efficiency by comparing the test results and the theoretical values of perfect mixing. We then verified the effects of engine speeds and irregular combustion to the trapping efficiency. Tests were conducted to clarify the relationship between the air/fuel ratio and HC concentration and mass HC emission, and the test results were compared with the theoretical values. In addition, a study was made on how to reduce the mass HC emission by optimizing air/fuel ratio. Next, we launched tests to study the effects of ignition timing on HC emissions as well as the ignition timing characteristics and throttle opening and engine speed.
1975-02-01
Technical Paper
750907
Takayoshi Mabuchi
This report describes a new type of simulation system - automatic operation equipment for motorcycles. In this system, all operations such as throttle, clutch and gear shifting are controlled automatically with command signals. This system could be used for the emission measurement standard modes and actual drive patterns. Therefore, this system could be used for various motorcycle simulation testing on a chassis dyanmometer. Further, durability tests for emission reduction devices could be performed with reliable and effective results using this system.
1975-02-01
Technical Paper
750905
J. A. Gunderson, D. K. Lawrence
This report documents the investigation of the technical and economic feasibility of using a carbon canister on board the vehicle to retain displaced hydrocarbon vapors during refueling. Denoted by the API as an Interim Report of Project EF-14, this report is a sequel to the Project's Phase I Report of April 1973, “Cost Effectiveness of Methods to Control Vehicle Refueling Emissions.” To initiate the design of a prototype carbon canister system capable of handling refueling vapor losses, studies were undertaken on a bench-test system to define the total amount of refueling vapor to be handled, vapor retention capacity of activated carbon, and purge capacity over a range of refueling conditions and fuel system parameters. In addition, extensive exhaust and evaporative emission tests were performed on the baseline vehicle and the modified vehicle. Detailed cost and effectiveness analyses were performed.
1975-02-01
Technical Paper
750904
D. Collins, R. D. Cuthbertson, R. W. Gawen, R. W. Wheeler
The development of a simple CVS particulate test and its application to various engine types is shown to quantify a number of problem areas. Research into the reduction of particulates in exhaust gases can be carried out more effectively by this technique than by the older optical methods. These investigations however lag far behind those into the better known gaseous emissions.
1975-02-01
Technical Paper
750903
Charles M. Urban, Karl J. Springer, John J. McFadden
This paper summarizes an investigation of reductions in exhaust emission levels attainable using various techniques appropriate to gasoline engines used in vehicles over 14,000 lbs GVW. Of the eight gasoline engines investigated, two were evaluated parametrically resulting in an oxidation and reduction catalyst “best combination” configuration. Four of the engines were evaluated in an EGR plus oxidation catalyst configuration, and two involved only baseline tests. Test procedures used in evaluating the six “best combination” configurations include: three engine emission test procedures using an engine dynamometer, a determination of vehicle driveability, and two vehicle emission test procedures using a chassis dynamometer. Dramatic reductions in emissions were attained with the catalyst “best combination” configurations. Engine durability, however, was not investigated.
1975-02-01
Technical Paper
750902
T. V. De Palma, C. H. Bailey
This paper discusses the use of an oxidation type catalytic converter for medium and heavy-duty gasoline powered trucks. It offers the highest reductions of HC and CO; and it is the simplest, most durable, and most cost effective system for reducing air pollution from trucks without fuel or driveability penalties.
1975-02-01
Technical Paper
750871
F. M. Dunlevey, R. R. Steiner
Vehicle durability data using the Gould NOx catalyst system is presented. Two 1973 vehicles accumulated 25, 000 AMA miles each demonstrating efficient and stable control of NOx, HC, and CO vehicle exhaust emissions. In additional tests, accurate fuel economy data using a 1975 California vehicle were taken. The vehicle system was optimized such that the fuel economy was improved by 2. 6% while meeting the 1978 emission standards of 3. 4 gram per mile CO, 0. 41 gram per mile HC, and 0. 4 gram per mile NOx.
1975-02-01
Technical Paper
750872
Mizuho Fukuda, Kazuo Osada
This paper describes and compares five types of catalytic structures devised for automotive honeycomb catalytic converters, all of whose honeycomb meshes vary in shape - regular triangle, regular hexagon, square, and corrugations (types A and B). Each honeycomb structure is analyzed as a two-dimensional frame structure, and its thermal deformation and thermal stress are discussed in comparison with those of the other types. The analytical results are examined for differences in mechanical properties, the effects of the outer cover and of the wire mesh support, the development of cracks, etc. Further, through the use of simple experimental models, the paper describes how the analytical results have been proven to be correct.
1975-02-01
Technical Paper
750869
W. R. Brandstetter, G. Decker, K. Reichel
The development of a 1600 can SCE with a divided combustion chamber and fuel injection into the prechamber ist described. Mathematical simulation was used to study the influence of several parameters. Single and multi-cylinder engine tests were carried out to determine the most suitable fuel mass fraction for the prechamber. The effectiveness of the lean thermal reactor was measured. Vehicles were tested accordingly to the CVS-procedure. PNA emissions and octane requirements were also determined. Some limited testing was done with methanol fuel. During the test Programm no specific problems on components were encountered.
1975-02-01
Technical Paper
750870
Kurt Obländer, Manfred Fortnagel
This paper gives the background for the development of the five-cylinder diesel engine, introduced as a passenger car first. It discusses the main design features of this engine, its combustion and fuel injection system, and the associated aspects of balancing. Performance, fuel economy and exhaust emissions of the engine result in very interesting vehicle features.
1975-02-01
Technical Paper
750848
David R. Nightingale
In order to supplement the on-going development work aimed at reducing emissions levels, in particular NO, in the exhaust of diesel engines a research programme was initiated to investigate the fundamental nature of NO formation. A rapid acting sampling valve to obtain gas samples directly from the combustion chamber of a running diesel engine was developed concurrently with a mathematical model for the formation of NO in diesel engines, based on the extended Zeldovich mechanism. Gas samples were obtained from the following types of diesel engine: i) A single spray sector of a large quiescent direct injection combustion chamber ii) A deep bowl direct injection combustion chamber employing inlet induced swirl iii) A Ricardo Comet V indirect injection combustion system. The temporal and spacial distribution of NO and the local air fuel ratio were determined in each case.
1975-02-01
Technical Paper
750796
Frank W. Leipold, Horst O. Hardenberg
A direct as well as an indirect injection system have been studied in regard to noise, exhaust emissions and fuel consumption on a V-10 diesel engine. The dependency of the sound pressure levels on engine speed, engine load and injection timing is described for both combustion systems. The noise reduction achieved by optimisation of injection timing is shown in relation to the respective changes in exhaust and smoke emission output and fuel consumption.
1975-02-01
Technical Paper
750889
Robert M. Siewert, Stephen R. Turns
A staged combustion engine has been evaluated in which pairs of cylinders are coupled in series. The first cylinder of the pair inducts and burns a homogeneous, fuel-rich mixture which produces exhaust products containing substantial amounts of combustibles (CO, H2, and HC) and only small quantities of NOX. These products are then cooled, mixed with additional air, and inducted into another cylinder for a second stage of combustion. Additional work is extracted in this second stage, where substantial cleanup of CO and HC occurs while maintaining a low level of NOX. Experiments with a two-cylinder research engine showed that low NOX emission could be obtained without sacrificing engine efficiency. However, approximately 40 percent more displacement is required to produce the same power as conventional SI engines. The sources of HC, CO, and NOX emissions were investigated, as were the effects of major engine variables on these exhaust emissions and fuel consumption.
1975-02-01
Technical Paper
750887
Keshav S. Varde
Operation of spark ignition engine under lean mixture condition is one of the several options that may be used to meet pollution and fuel economy standards. In such an operation various factors influence the combustion phenomonon. To examine these, a study is conducted in a static chamber using lean propane air mixtures of different stoichiometry. Effects of ignition energy, electrode geometry, location of ignition source and temperature profile in the initial reaction zone are investigated. It was found that increasing ignition energy accelerated flame up to a certain point; any futher increase in energy had little effect on the flame acceleration. The rate of pressure rise also showed similar pattern. Temperature in the reaction zone was lower when the ignition point was near the wall than away from it; the temperature profile was mapped using laser interferometer techniques. Round tipped electrodes showed better repeatability and yielded lower ignition energy than the flat tipped.
1975-02-01
Technical Paper
750888
Dusan Gruden
The development of vehicle combustion engines today is characterized by the effort to reduce exhaust gas emission and fuel consumption and to conserve the good properties of the combustion engine at the same time. As, at least for the years to come, there will be no chance for the utilization of the alternative special drives, PORSCHE is intensely dealing with the further development of the conventional combustion engine as well as of the stratified-charge-chamber engine. With their stratified-charge engine (SKS) PORSCHE has tried to create optimum conditions for each of the combustion phases. The result was a divided combustion chamber with a three-stage combustion. The system was tried on single-, six-, and eight-cylinder engines and led to good results under stationary conditions on the testing rig as well as under unstationary driving conditions.
1975-02-01
Technical Paper
730530
Clark E. Fegraus, Charles J. Domke, James Marzen
The Office of Air Programs, U. S. Environmental Protection Agency, sponsored in 1972 a study of emissions from light-duty vehicles in six cities to determine the contribution to atmospheric pollution by the vehicle population. AESi, under contract to EPA, performed comprehensive tests on 1020 vehicles of the 1957-1971 model years to determine levels of hydrocarbons (HC), carbon monoxide (CO), carbon dioxide (CO2), and oxides of nitrogen (NOx) exhaust emissions. Vehicle exhaust emissions, as measured by the 1972 and 1975 Federal Test Procedure, were of similar magnitude among all cities except Denver, Colo. CO and HC effluents were significantly higher at high altitude, but NOx were significantly lower. Emission results by manufacturers were relatively uniform.
1975-02-01
Technical Paper
750069
Roy A. Renner, Michael Wenstrom
The California Legislature conducted an investigation into the low emission properties of steam-powered automobiles, 1972-74. Two steam propulsion systems were built and installed into sub-compact cars suitable for urban driving. The Aerojet Liquid Rocket Co. installed a steam turbine in a Chevrolet Vega, while Steam Power Systems built a piston engine system for a car of special design. The project demonstrated that it is possible to reduce exhaust emission levels to less then those required by the 1978 Federal standards. Road performance was adequate for urban-suburban driving. Fuel consumption was higher than comparable internal combustion-powered vehicles. Guidelines for future improvements are given.
1975-02-01
Technical Paper
750070
Philip H. Schneider
A low-pollution steam-powered automobile using a reciprocating piston expander was built and tested for the California Clean Car Project. The performance test results of the automobile and the powerplant are presented herein. The primary test goals which have been successfully demonstrated with the current vehicle are low exhaust emissions and low noise levels. Areas that require improvement in a next-generation vehicle include fuel economy, acceleration, power, reliability, and start-up time. Plans for improving the vehicle powerplant are discussed briefly.
1975-02-01
Technical Paper
750071
Jay W. Carter
A steam powered Volkswagen has been tested by the Environmental Protection Agency and meets the strict 1977 emission levels without the use of add-on emission control devices. The steam system is unusual in its use of high pressure (up to 2500 psi), high temperature steam (1100°F) in conjunction with a high speed reciprocating expander (up to 6000 rpm), constant expansion ratio, variable pressure boiler, and a conventional automotive transmission to achieve an extremely compact design of high thermal efficiency.
1975-02-01
Technical Paper
750053
K. Zeilinger, A. W. Hussmann
Engines of passenger cars operate almost exclusively under transient conditions. However, all influencing parameters are tailored to steady-state operation. An experimental investigation was made to determine if the correlations between emissions and engine operation on the one hand and on the other hand, the influencing parameters which are well known for steady-state conditions are valid also for transient operation. The basic concept of the investigations and the experimental setup are described briefly. The results show clearly the differences between steady-state and transient operation, which are mainly caused by temperature effects.
1975-02-01
Technical Paper
750096
J. G. Cohn, W. A. Mannion, C. E. Thompson, J. G. Hansel
Emission of SO3 or of sulfates can be virtually eliminated from catalytically controlled vehicles by operation in three way conversion mode as well as by operation of oxidation catalysts without air pumps. Hydrogen sulfide is not detected during normal excursions into the rich air-fuel region. Combined with the fact demonstrated by Volvo that vehicles equipped with Engelhard three way conversion catalysts meet or are lower than the 1975-76 California emission standards after 50,000 miles of driving, a viable solution exists for emission control of all pollutants including sulfates.
1975-02-01
Technical Paper
750095
M. Beltzer, R. J. Campion, J. Harlan, A. M. Hochhauser
Noble metal oxidation catalysts have been shown to convert gasoline sulfur to automotive particulate sulfate emissions. A study was carried out in a laboratory bench scale reactor to evaluate the effect of vehicle operating conditions and catalyst type on the conversion of SO2 to SO3. The factors studied included catalyst temperature, exhaust gas O2 content and space velocity. The results are compared with data from a vehicular study designed to assess total sulfur emissions from catalyst-equipped cars. This study indicates that control of exhaust sulfate emissions may be achieved through close control of the oxygen content of exhaust gas and that the choice of catalyst affects the degree of conversion of SO2 to SO3 and the amount of oxidized sulfur retained in the catalyst system.
1975-02-01
Technical Paper
750097
Robert H. Hammerle, Mati Mikkor
With the use of a simulated exhaust system, the sulfuric acid and sulfur dioxide emission from a monolith noble-metal oxidation catalyst (Engelhard IIB) is measured. It was found that the storage rate of sulfur onto an initially sulfur-free catalyst decreases to a few percent of the sulfur rejection rate within 3-4 h. The amount of sulfur on the catalyst when the catalyst is in equilibrium with 20 ppm sulfur in the gas phase varies between 0.3 weight percent of the catalyst at about 400°C to 0.1 weight percent at 600°C. The sulfur can readily desorb from the catalyst if the gas phase sulfur content is lowered or if the catalyst temperature is increased. It was found that the conversion of sulfur dioxide to sulfuric acid reaches thermodynamic equilibrium at temperatures of 400-500°C and space velocities of 30,000 h-1. These conditions correspond approximately to a small V8 engine at 20 mph cruise.
1975-02-01
Technical Paper
750090
Ronald L. Bradow, John B. Moran
A review of the available data on sulfate emissions methods and emissions rates from both catalyst-equipped and noncatalyst cars has been made. Air-dilution methods of various sorts appear to give similar sulfates emissions results, comparable with those obtained by controlled condensation procedures. Mobile source SO2 measurements technology requires much more attention. At present, only the hydrogen peroxide oxidation to sulfate has been demonstrated to give reliable results. Summaries of several hundred catalyst and non-catalyst emission rates are treated to estimate California and 49-state emissions. A cruise-mode emission rate of about 0.03 g/mile appears appropriate for both monolithic and pelleted catalysts in 49-state cars.
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