Display:

Results

Viewing 22051 to 22080 of 23342
1975-02-01
Technical Paper
750225
G. S. Iles
A novel temperature sensor is described, consisting essentially of a composite platinum film firmly bonded to a ceramic substrate. The film is protected from the corrosive effects of gaseous environments by an overglaze of impervious glass, forming a device that is mechanically and thermally robust. Since the sensing unit does not require further protection by encapsulation in a metal or ceramic sheath, it responds very rapidly to thermal changes. The sensor possesses short and long term electrical characteristics similar to those of wire-wound platinum resistance thermometers, but is less costly. It can operate over a wide range of temperatures up to about 1,000°C. The versatile construction of the sensor renders it, in its cylindrical form, eminently suitable for monitoring the thermal changes occurring within catalyst emission control units on internal combustion engines.
1975-02-01
Technical Paper
750223
Heinrich Dueker, Karl-Hermann Friese, Wolf-Dieter Haecker
The Λ-sensor is used within the scope of the Bosch emission control system, representing a closed control loop. In principle, it is an oxygen concentration cell with an oxygen ion-conducting solid electrolyte which provides a sharp voltage step at the stoichiometric air-fuel ratio, serving as a control signal. Zirconia ceramic stabilized with certain metal oxides is used as the solid electrolyte. The electrical and mechanical properties of the ceramic depend, above all, on the type and concentration of the stabilizing oxide and on the manufacturing conditions. Using ceramic materials which are described, sensors can be produced that make possible exact control of the stoichiometric A/F in a temperature range of 300/400-900°C. The lifetime of the sensor, which depends on the operating conditions, can be taken as about 15,000 miles of driving distance. With this sensor, exhaust emissions can be kept below the limits specified for 1977-1978 in the United States.
1975-02-01
Technical Paper
750204
J. M. Perez, L. C. Broering, John H. Johnson
This is the fourth in a series of tests conducted as a Coordinating Research Council cooperative program to evaluate the measurement methods used to analyze diesel exhaust gas constituents. A multi-cylinder engine was circulated to 15 participants who measured emissions at three engine conditions. All 15 participants measured nitric oxide and carbon monoxide with several laboratories measuring nitric oxide by both NDIR (Non-Dispersive Infrared) and CHEMI (Chemiluminescence). Some participants also measured carbon dioxide, nitrogen dioxide, oxygen, and unknown span gases. The test results are compared with the Phase III cooperative tests which involved simultaneous measurement of emissions by participants. The precision of the results was poorer in Phase IV than Phase III.
1975-02-01
Technical Paper
750350
Harald Mauch
Misfiring of engines with fouling spark plugs is caused by a loss of ignition energy in the deposits of the spark plugs. This loss of energy can be avoided and a steep ascent of voltage achieved by connecting an ionizing gap with suitable breakdown voltage in a series close to each of the spark plugs. Vehicle application requires ionizing gaps with high stability of breakdown voltage over life time. Design and performance of the new BOSCH Ionizing Gap are explained.
1975-02-01
Technical Paper
750348
Richard W. Johnston, John G. Neuman, Paul D. Agarwal
Emission control requirements have prompted optimization studies of many engine parameters, such as engine geometry, fuel preparation, and ignition. This paper describes an experimental ignition system which permits these studies with a spark that has an adjustable power level and independent programmable arc duration. This new ignition system uses inductive-discharge to strike the arc and, together with transformer action, sustains the arc from a single coil for any duration. Its principal features are: (1) programmable arc duration, (2) high arc current for full arc period, (3) fast voltage rise, (4) low average battery current drain, (5) no intermediate power supply, and (6) since it uses inductive storage, it can be integrated into present electronic systems if the need is proven. Limited test results are presented to show the effect of arc duration on engine operation.
1975-02-01
Technical Paper
750334
E. Eisele, H. Hiereth, H. Polz
After dealing briefly with the mode of operation of the Comprex® pressure wave supercharger, a report is given on its general advantages and drawbacks as well as on experience gained in practical operations on the supercharging system, using a 2.2 dm3 prechamber passenger car diesel engine. The most important problems which occurred here and the performance and exhaust emission figures resulting from rig and road test measurements are discussed.
1975-02-01
Technical Paper
750332
Karl J. Springer, Ralph C. Stahman
Four diesel-powered passenger cars were subjected to a wide variety of emission and economy evaluations, and the results are presented in this paper. The four production cars included a 1972 Mercedes-Benz 220D, a 1973 Peugeot 504D, an Opel Rekord 2100D, and a Nissan diesel-powered Datsun. Tailpipe emissions were measured by the 1975 Light Duty Federal Test Procedure for gaseous emissions, fuel economy (carbon balance and gravimetric) and smoke. Smoke and gaseous emissions were also measured by chassis dynamometer versions of the 1974 Federal heavy-duty procedures. Odor and related instrumental-chemical measurements were made under seven steady-state and three transient conditions. Odor was measured by a trained panel and the analytical system developed by A. D. Little, Inc., under CRC contract. Noise measurements were taken during SAE driveby and a variety of of interior-exterior conditions.
1975-02-01
Technical Paper
750330
M. L. Monaghan, J. J. McFadden
This paper describes a study which was carried out to determine the feasibility of the diesel as a light duty power plant for American use. As a result of a literature survey and a specific configuration study, nine 96 kW diesel power plants were examined in detail. Further examination of the diesel power plants indicated that only the direct injection four-stroke configurations could meet the primary emission targets using current technology. It was concluded, however, that the diesel engine could provide a viable power plant for light duty vehicles and that considerable improvements in fuel consumption and overall running costs could be obtained.
1975-02-01
Technical Paper
750958
J. Dillard Murrell
The EPA certification data base is the most extensive available body of information relating engineering variables to fuel economy. The range and distributions of these variables are presented in a non-sales weighted context. A multiple regression analysis, performed with careful attention to selection of optimum non-linear forms for some of the variables, shows that the most significant determinant of fuel economy is the parameter CID × N/V. Vehicle weight is second. A sensitivity study on the isolated fuel economy effects of CID, N/V and weight confirms the superiority of CID as an influencing factor, and opens avenues for improving the structure of the forms of these variables in future regression equations. A method is devised for quantifying ignition timing over a driving cycle in terms of a single “labeling” value usable as an engineering variable. Although not illustrated, the method is applicable to carburetion in similar fashion.
1975-02-01
Technical Paper
750929
John W. Bjerklie, Elton J. Cairns, Charles W. Tobias, David Gordon Wilson
Two successive surveys and round-robin interviews were conducted to determine if there might be in the offing for automobiles an alternative engine which would exhibit low emissions meeting the most stringent requirements. Comparison between engines were couched in terms of selected “acceptability factors” which went well beyond emissions, alone. The overall acceptability was evaluated considering emissions, customer requirements for an engine, manufacturers' requirements for an engine, and engine efficiency and fuel versatility. An attempt was made to establish a time scale as to R and D requirements and eventual production. Comparison of all engines was made with equivalent pre-control Otto cycle engines as the standard. Alternative engines were deemed to be any power plant that was not based on spark ignition Otto cycle engines, or diesel engines. The remaining heat engines largely used continuous combustion as the heat source.
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.
Viewing 22051 to 22080 of 23342

Filter