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1984-10-01
Technical Paper
841334
Lois E. Freeman, Granger K. Chui, Daniel A. Crowl, Richard J. Roby
A single cylinder indirect injection diesel engine was used to evaluate the emissions, fuel consumption, and ignition delay of non-petroleum liquid fuels derived from coal, shale, and tar sands. Correlations were made relating fuel properties with exhaust emissions, fuel consumption, and ignition delay. The results of the correlation study showed that the indicated fuel consumption, ignition delay, and CO emissions significantly correlated with the H/C ratio, specific gravity, heat of combustion, aromatics and saturates content, and cetane number, Multiple fuel properties were necessary to correlate the hydrocarbon emissions. The NOx emissions did not correlate well with any fuel property. Because these fuels from various resources were able to correlate succesfully with many of the fuel properties suggests that the degree of refinement or the chemical composition of the fuel is a better predictor of its performance than its resource.
1984-10-01
Technical Paper
841374
D. W. Naegeli, D. M. Yost, E. C. Owens
Several test programs have shown that the combustion of methanol in spark ignition engines can cause unusually high corrosive wear of the upper cylinder bore and ring areas. In this study, a 2.3-liter engine fueled with methanol was operated in a nitrogen-free atmosphere to determine the importance of nitric acid in the corrosion mechanism. A 20-hour steady-state test was carried out using neat methanol as the fuel and a mixture of oxygen, argon, and carbon dioxide in place of air. Only trace amounts of NOx and nitric acid were found in the exhaust products during this test. The wear, indicated by iron buildup in the lubricant, was found to be essentially the same in the nitrogen-free test as that detected in baseline engine tests combusting methanol-air mixtures. It was concluded that nitric acid does not play a role in the corrosion mechanism.
1984-10-01
Technical Paper
841362
Richard L. Rentz, Peter W. McCallum, James S. Moore, Thomas J. Timbario, Richard T. Alpaugh
Advanced gas turbine (AGT) engines may exhibit widened fuel tolerance as well as improved thermal efficiency relative to current spark-ignition engines. However, the inherent adaptability of the engine to a variety of fuels may not be reflected in the practical fuels adaptability of gas turbine engine vehicles which are acceptable from commercial and regulatory perspectives. This paper presents the results of a study of the primary issues surrounding the fuels adaptability of commercial AGT vehicles. Topics addressed include candidate fuels and fuel characteristics, and AGT combustion and fuel system characteristics. Results of an analysis of relationships between engine characteristics and fuel properties are presented as well as observations concerning future research.
1984-10-01
Technical Paper
841364
J. C. Wall, S. K. Hoekman
The effects of fuel composition on diesel exhaust particulate emissions have been studied at several steady-state operating conditions using a heavy-duty laboratory engine. Particulate emissions were influenced by three primary fuel factors: sulfur content, aromatics content, and volatility. At all but lightly loaded operating conditions, fuel sulfur was the dominant fuel factor in particulate formation. Fuel sulfur affects particulate emissions primarily by formation of sulfate (as sulfuric acid) and associated “bound” water and, to a lesser degree, by increasing the amount of soluble organic material collected. Aromatics and volatility influence the amount of carbonaceous material formed. Five polynuclear aromatic hydrocarbon (PAH) compounds were measured in the soluble organic fraction. Engine operating conditions greatly affected PAH levels; however, no strong influence of fuel composition on PAH concentrations was observed in the normal range of No. 1 - No. 2 diesel fuels.
1984-10-01
Technical Paper
841354
R. Bruce Michael
Twenty-nine in-use automobiles with three-way catalyst emission control systems were misfueled with leaded gasoline in order to quantify the emissions effects. The vehicles used between four and twelve tanks of leaded gasoline. The leaded gasoline had an average of 1.0 grams Pb per gallon. Four different test programs were conducted with different misfueling intensities (rates) and mileage accumulation schedules. The Federal Test Procedure and several short tests were conducted at various stages. The results of the program indicate that vehicle emissions are mainly affected by the amount of lead passing through the engine and secondarily by the rate of misfueling.
1984-10-01
Technical Paper
841356
Frank Black, William Ray, Foy King, William Karches, Ronald Bradow, Ned Perry, John Duncan, William Crews
Apportionment of air pollution to sources requires knowledge of source emission strengths and/or chemical and physical characteristics. The literature is deficient in data useful for this purpose for heavy-duty motor vehicles, which can be important sources of air pollution in certain microenvironments. Emission factors are developed in this study for heavy-duty gasoline trucks using chassis dynamometer simulations of urban driving conditions. The sensitivity of the emissions to such considerations as the characteristics of the speed-time driving schedule, vehicle payload, and chassis configuration are examined. Emissions characterization includes total and individual hydrocarbons, aldehydes, carbon monoxide, oxides of nitrogen, total particulate matter, particulate organics, lead, bromine, chlorine, and the fraction of total particulate less than 2 μm. Preliminary comparisons of emissions obtained using transient engine and transient chassis test procedures are also reported.
1984-10-01
Technical Paper
841357
Craig A. Harvey, Penny M. Carey, Joseph H. Somers, Robert J. Garbe
The increased interest in use of methanol makes it important to determine what levels of methanol and formaldehyde emissions may be acceptable. This paper reviews the available health data for methanol and formaldehyde to define what approximate ranges of concentrations, termed ranges of concern, could be acceptable from a toxicological viewpoint. Air quality models are then used to predict the in-use fleet average exhaust emission levels in localized situations (heavily impacted by mobile sources) corresponding to these ranges of concern. Using predicted fleet compositions, approximate target emission levels are given for the light-duty portion of the fleet which could yield these fleet averages. Finally, there is a brief summary of available methanol and formaldehyde emissions data from neat methanol-fueled vehicles which are compared to the target levels.
1984-10-01
Technical Paper
841411
Gerald L Gallagher, Wanda M. Lauderdale
Over the past two years, the Colorado Air Pollution Control Division has conducted a series of studies dealing with significant increase in dieselization and the resultant increase in diesel emissions emitted by both light-duty diesel vehicles and the large number of heavy-duty diesels. This paper presents the findings from these studies. It discusses the effects which diesel exhaust particulates will have on citizens of Colorado and discusses recommended control strategies.
1984-10-01
Technical Paper
841397
Daniel L Raley, Peter W. McCallum, William J. Shadis
In recent years, several investigators have characterized and measured hydrocarbon components, including benzene, in vehicle exhaust. This paper presents an analysis of benzene exhaust emission data reported from approximately 100 light-duty vehicles. Results indicate that on average, benzene exhaust emissions from catalyst-equipped vehicles are significantly less than those from non-catalyst vehicles. In addition, benzene exhaust emissions from 3-way catalyst vehicles appear to be significantly less than those from oxidation catalyst vehicles, on average. These observations parallel analogous average reductions in total hydrocarbons, indicating that modern catalyst-based exhaust emission controls reduce benzene emissions to approximately the same degree as they reduce total hydrocarbons. Also, benzene evaporative emissions from 3-way catalyst vehicles appear to be substantially less than those from oxidation catalyst vehicles.
1984-10-01
Technical Paper
841396
Harry E. Dietzmann, Tim P. Lee
This paper presents results of research conducted to characterize exhaust emissions for diesel engines typically used in forklift operation. Emissions characterization involved three fuels (MIL-F-46162A(MR), MIL-F-46162B(ME), and EPA DF-2 Phillips Reference Fuel) and four engines, tested under a variety of steady-state conditions. Gaseous, particulate and unregulated emissions were included in the emissions characterization. Unregulated emissions included sulfur dioxide, sulfate, aldehydes, organic sulfides, odor, phenols, and nitroaromatics. In addition, selected engine malfunctions were evaluated to determine the effect on emissions. Results of this study, actual ambient measurements during diesel forklift operation in storage igloos and modeling studies will allow the U. S. Army to determine emission limits for diesel vehicles intended for use in enclosed areas.
1984-10-01
Technical Paper
841394
Kenichirou Takama, Kiyoshi Kobashi, Kiyohiko Oishi, Tokuta Inoue, Takeshi Kogiso
Periodic regeneration of the diesel particulate trap is essential to maintain the collection efficiency and exhaust gas hack pressure at acceptable levels. The objectives of this study are to describe the phenomenology of ceramic foam filter regeneration process and to present its mathematical model. Further simulation study is carried out to estimate the effects of various factors including fuel additive on the ignition and the filter bed temperature and to investigate conditions of excessive temperature which could result in filter destruction. The model is based on the assumption that the regeneration process is composed of two steps. The first step is the additional heat supply from the external energy source, and the second step is the spontaneous combustion propagation. The results from the analytical model agreed very well with the experimental results.
1984-10-01
Technical Paper
841395
David L. Hilden, William J. Mayer
An apparatus was developed for the determination of the engine oil contribution to both total and extractable particulate exhaust emissions from diesel-powered vehicles during cyclic operation on a chassis dynamometer. For the five vehicles tested, the percentage of the total particulate material that was derived from engine oil ranged from 7 to 14%. Between 14 and 26% of the total particulate material was extractable with benzene-ethanol (80-20) solvent. Oil contributed from 30 to 55% of the extractables in most cases. Engine design and oil formulation generally appeared to have only small effects on the oil contribution to the particulate emissions. A 1982 model-year vehicle with a 1.8L engine was an exception, since its oil contribution to the total and especially to the extractable particulate emissions (14 and 95%, respectively) was significantly greater than for any of the other vehicles.
1984-10-01
Technical Paper
841385
Larry E. Wagner, Stanley J. Clark, Mark D. Schrock
The primary problems associated with straight soybean oil as a fuel in a compression ignition engine are due to high fuel viscosity. Transesterification provides a significant reduction in viscosity, thereby enhancing the physical properties of the fuel to improve engine performance. Methyl, ethyl, and butyl esters of soybean oil revealed fuel properties similar to diesel fuel. Engine wear, deposits, performance, and emissions are reported for each of the ester fuel's and reference diesel fuel's 200-hour engine tests. Analysis of lubricating oil samples are also presented as well as complete fuel injection system test results.
1984-10-01
Technical Paper
841383
David J. Miller, David A. Drake, James M. DeJovine, George Yogis
Results of compatibility studies of vehicle fuel system components and materials with gasoline containing 4.5 volume % methanol/4.5 volume % gasoline-grade tertiary-butyl alcohol are presented. Vehicles from on-the-road use over several years showed no increased corrosion of metals or deterioration of elastomers and plastics when compared to hydrocarbon-only fuels. Vehicle exhaust emissions remain unchanged or are reduced. Charcoal canisters and evaporative emissions do not appear to be differentially affected.
1984-10-01
Technical Paper
841381
Svend Henningsen
HC emissions and ignition delay were investigated in a research single-cylinder DI diesel engine. Correlations were made between the measurements and different air-fuel mixing parameters calculated from a gas-jet spray model and expressions from the literature. The change in ignition delay was caused by varying engine inlet conditions of pressure and temperature and by adding a special cetane improver to No. 2 diesel fuel. In order to be able to interpret the experimental results a zero-heat-transfer heat release model was used in evaluation of the engine pressure data. It was found that the too-lean-mixed fuel could explain a maximum of 20% of the HC emission; the remaining amount is caused by other sources.
1984-10-01
Technical Paper
841379
E. N. Balles, J. A. Ekchian, John B. Heywood
High levels of hydrocarbon emissions during light load operation keep the direct injection stratified charge engine from commercial application. Previous analytical work has identified several possible hydrocarbon emissions mechanisms which can result from poor in-cylinder fuel distribution. Poor fuel distribution can be caused by erratic fuel injection. Experiments conducted on a single cylinder DISC engine show a dramatic increase in the cycle to cycle variation in injection characteristics as engine load decreases. This is accompanied by an increase in cycle to cycle variation in combustion behavior suggesting that degradation in combustion results from the degradation in the quality of the injection event. Examination of combustion and injection characteristics on a cycle by cycle basis shows that, at light load, IMEP and heat release do not correlate with the amount of fuel injected into the cylinder.
1984-10-01
Technical Paper
841380
A. C. Alkidas
The potential sources of hydrocarbon (HC) emissions from a single-cylinder, divided-chamber diesel engine were investigated in this study. To evaluate the relative importance of these sources, the variations of HC emissions with engine speed, air-fuel ratio, combustion timing, intake-air temperature, coolant temperature and oil temperature were examined. Included in the diagnostics of this investigation were: ignition-delay measurements, combustion-chamber surface temperature measurements and heat-release modeling. Lubricating oil was found to contribute significantly to HC emissions. In addition, the results suggested that bulk quenching of flame and non-flame reactions is a primary source of HC emissions. On the other hand, lean mixing during the ignition delay period and wall interactions appear to be secondary sources.
1984-10-01
Technical Paper
841458
Charles Witt
AIR 1839 is being issued by the SAE E-32 Committee on Aircraft Gas Turbine Engine Monitoring. It provides information and guidance on the selections, installation and use of airborne engine vibration monitoring systems and their elements.
1984-10-01
Technical Paper
841459
Larry R. DeMott, Charles E. Bentz
Aerospace Information Report (AIR) 1871 has been prepared by the SAE E-32 Committee on Aircraft Gas Turbine Engine Monitoring., The purpose of the AIR was to document some of the valuable lessons learned from developmental and operational gas turbine engine monitoring systems. This technical paper discusses the activity of the Lessons Learned Sub-Committee and provides an overview of AIR 1871.
1984-10-01
Technical Paper
841461
R. Halliday, R. D. Jackson
For an aircraft flying similar routes each day the engine baseline characteristic can be predicted and compared to the actual characteristic. The engine and aircraft parameters are monitored and entered into a programmable pocket calculator which normalises the gas generator speed (Ng), inter turbine temperature (ITT) and fuel flow (Wf) and corrects for the baseline altitude and speed. The delta Ng, ITT, Wf between the actual and baseline at the normalised output power are plotted against engine running time to give a trend plot. Deviations can be interpreted to determine when engine maintenance, including hot section inspections (HSI's), is required. HSI's scheduling based on trend plots is providing a maintenance cost saving.
1984-10-01
Technical Paper
841460
Henk C. Vermeulen
AIR 1873 is being issued by the SAE E-32 committee on Aircraft Gas Turbine Engine Monitoring. It provides guidance on the specification, application and use of a Limited Engine Monitoring System which is defined as an EMS where the measurement parameters are ussually limited to those that are provided as part of the standard aircraft instrumentation.
1984-10-01
Technical Paper
841462
Joseph D. Dupcak, Paul Deppe, Rich Prevatt
In January 1983, the Naval Air Systems Command authorized a coordinated NAVAIRTESTCEN/Lockheed study to establish the feasibility of a low-cost procedure for monitoring U.S. Navy P-3C T56-A-14 engine performance from inflight recorded cockpit instrumentation. The resulting study, still in progress, was organized into three phases. In the first phase, a flight test program was conducted to obtain actual engine performance data from which performance standards or baselines could be developed. In the second phase, algorithms and procedures for implementing inflight engine performance trending were established. Finally, in January of 1984 a fleet trial was initiated. This paper discusses the user's motivation for such a system, describes the flight test program and associated analyses, outlines the proposed engine monitoring system, and concludes with a status report on the ongoing fleet trials.
1984-10-01
Technical Paper
841399
K. C. Tsao, C. L. Wang, E. M. Miller
Unleaded gasoline containing 5, 10, and 15% of water by volume were tested in a modified spark ignition engine. Engine power output, fuel consumption, efficiency and emissions were measured and reported. Pressure time records of each test run were analyzed to calculate the fuel mass burned fractions. The air cooled single cylinder engine was run at 2000 RPM and at a compression ratio of 7.5. Generally, the emissions of lower carbon monoxide, oxides of nitrogen and higher unburned hydrocarbons were observed as the volume percent of water in fuel was increased. The power output was increased on the order of 3.8 to 14% when the base fuel containing 5 to 15% water was used. These preliminary performance data conducted with a single cylinder engine suggest that the water-gasoline fuel compares favorably both in mean effective pressure and fuel consumption to that of a gasoline fueled engine.
1984-09-01
Technical Paper
841239
D. J. Schuring, W. J. Woehrle
A brief discussion of the physical concept of tire energy loss and its relation to automobile performance is followed by a general definition of tire rolling loss. The effects of bearing losses, load, pressure, speed, road surface texture and other important factors on rolling loss are explained, and conclusions are drawn with respect to a fair representation of these factors in a generally accepted procedure for measuring tire rolling loss. General test requirements are outlined, and suggestions are made for a unified international test procedure.
1984-09-01
Technical Paper
841244
K. G. Duleep
In spite of stable emission standards in force since 1981, automotive emission control technology has contined to evolve at a very rapid pace. In this paper, a very detailed forecast of emission controls for U.S. fleet of new cars is described. Forecasts of emission control technology mix by every combination of fuel system/catalyst system/secondary air system/EGR system are derived. Data on the fleet mix of emission controls is presented for the 1982-1990 time frame. Each of these different types of systems have different failure modes that lead to significantly different malperformance model emissions. Using data derived from emissions tests of vehicles that were intentionally disabled, estimates of the emissions from malperforming vehicles of the future are drawn. The estimates may form the basis of in-use emissions forecasts in the future.
1984-09-01
Technical Paper
841281
C D DE BOER, J A JEYES
SYNOPSIS Various proposals for more stringent emission legislation have been made for the medium term future in Europe. Set against these proposals is the intensified search for improved vehicle fuel economy and the probable result that overly stringent emission control would decrease fuel economy. The paper will discuss interaction of fuel economy and emission control in Europe based on a survey of the literature. The performance and operating cost of a number of alternative control strategies and engines will be compared using a current conventional gasoline engine as a basis.
1984-09-01
Technical Paper
841284
D GRUDEN, H RICHTER
1984-09-01
Technical Paper
841256
D. R. Hamburg, M. J. Throop
Vehicle chassis dynamometer tests were performed to compare predicted and measured total feedgas emissions and fuel economy for dynamic operation of an engine. In general, these tests showed that predictions based on steady-state mapping data agreed well with measured values except for NOx emissions. Subsequent engine-dynamometer tests indicated that the discrepancy between predicted and measured NOx emissions was due to competing effects of combustion chamber wall temperature and dynamic EGR time response. A technique was developed which utilized the results of a simple transient test to improve the accuracy of predicting NOx emissions when EGR time response was not a factor. The effect of degraded EGR time response on both instantaneous and total NOx emissions was also explored.
1984-09-01
Technical Paper
841288
K P MAYER
SYNOPSIS The current status and development trends of light duty diesel engines equipped with a multi-spray direct injection combustion system are described. Fuel consumption maps of a naturally aspirated and a turbocharged engine show that competitive performance and best fuel economy can be achieved. As a means for the reduction of combustion noise a “split injection device” is installed in the high pressure part of the fuel system. It permits a reduction of the amount of fuel injected during the ignition delay and consequently reduces the rate of pressure rise and maximum cylinder pressure. In addition, also a reduction of exhaust emissions is experienced. Advanced piston technology is presented as a feature for a further improvement of performance and fuel economy.
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