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1983-02-01
Technical Paper
830085
Otto A. Ludecke, David L. Dimick
The EPA has established stringent requirements for levels of particulates emitted from the exhaust of diesel passenger cars. This paper summarizes six years of development activities directed towards reduction of diesel passenger car particulates. A series of conceptual approaches have been experimentally evaluated, leading to development of a regenerative particulate trap. Alternate trapping material investigations, regeneration systems, and total trap systems are reviewed. The current status of this development and required technical needs are identified.
1983-02-01
Technical Paper
830086
B. Wiedemann, U. Doerges, W. Engeler, B. Poettner
Due to good trapping abilities, the ceramic trap filter was chosen for the reduction of the particulate emission of Diesel engines. Both, tests and the analysis of the regeneration kinetic show that in real-world application the lite-off limit of 500 °C may not be exceeded. The minimum exhaust gas temperature necessary for regeneration without the use of a catalyst, can be reduced to approx. 200 °C to 250 °C with the use of fuel additives. The use of additives for the filter regeneration showed excellent results in real-world conditions as well as with endurance tests. There was no significant change in emissions or specific fuel consumption about 20,000 km as compared to the operation without additives. The regeneration dependability however, is questionable because of the destruction of the filter.
1983-02-01
Technical Paper
830082
Yoji Watabe, Koichi Irako, Toshiyuki Miyajima, Toshio Yoshimoto, Yuichi Murakami
“Trapless” Trap, which makes possible the effective collecting of particulates in diesel exhaust gas and their simultaneous combustion has been developed by use of a ceramic foam in combination with catalysts containing copper salt. From a TEM photograph, it was observed that the particulate was rapidly oxidized by mobile copper ion, showing worm-eaten like spots. Screening of various base metal salts by TGA presented CUCl2-KCl-NH4VO3 and CuCl2-KCl-(NH4)6Mo7O24 as very active catalysts for diesel particulate oxidation. They had thermal stability up to 900°C when they were supported on titania. The results obtained by measuring the back pressure using 1.8L diesel engine suggest the above trap to be a self-cleaning trapless trap.
1983-02-01
Technical Paper
830084
Charles M. Urban, Larry C. Landman, Robert D. Wagner
Methods for particulate (and associated organics) emissions control were evaluated in several diesel cars. Of the methods investigated, only “particulate traps” provided large reductions in particulate emissions. Traps evaluated included metal mesh and ceramic monolithic configurations, catalyzed and uncatalyzed. One of the cars, with a ceramic trap installed, completed fifty thousand miles of distance accumulation. No significant deterioration of emissions occurred over those fifty thousand miles.
1983-02-01
Technical Paper
830083
W. R. Wade, J. E. White, J. J. Florek, H. A. Cikanek
Thermal and catalytic techniques for regenerating particulate traps were assessed. The thermal technique used a burner which heated engine exhaust to the ignition temperature of the particulates to achieve over 90% regeneration effectiveness. HC, CO and particulate emissions resulting from combustion of particulates and burner exhaust were 25 to 50% of the allowable vehicle emissions for one CVS cycle. The fuel consumed by the burner was 9% of the fuel consumed by a vehicle over one CVS cycle. Problems with burner nozzle clogging, ignition reliability, trap durability and control system requirements were identified. In the catalytic technique, Diesel fuel containing .5 gm/gal lead and .25 gm/gal copper lowered the ignition temperature of the particulates by 425°F so that periodic regeneration occurred. The trap collected nearly all of the lead and copper resulting in limited trap life, and deposits on the engine fuel nozzles tended to increase HC emissions.
1983-02-01
Technical Paper
830437
Joachim Staab, Horst Klingenberg, Dieter Schürmann
The effort in manpower and equipment and the expense in money and time involved in carrying out the various emissions tests have considerably increased over the past years. The same holds true for the fuel economy measurements. The present-day emissions testing practice calls for complex gas sampling and dilution systems (CVS) and for a big variety of different analyzing devices. The development of a unique instrument with which the interesting emission components can be measured simultaneously and directly behind the exhaust pipe would mean a decisive improvement of this situation. In an intensive study possible measurement methods were compared and a way was pointed-out to construct such an instrument.
1983-02-01
Technical Paper
830457
Paul R. Miller, Jackson Scholl, Susan Bagley, David Leddy, John H. Johnson
Physical, chemical, and biological characterization data for the particulate emissions from a Caterpillar 3208 diesel engine with and without Corning porous ceramic particulate traps are presented. Measurements made at EPA modes 3,4,5,9,lO and 11 include total hydrocarbon, oxides of nitrogen and total particulate matter emissions including the solid fraction (SOL), soluble organic fraction (SOF) and sulfate fraction (SO4), Chemical character was defined by fractionation of the SOF while biological character was defined by analysis of Ames Salmonella/ microsome bioassay data. The trap produced a wide range of total particulate reduction efficiencies (0-97%) depending on the character of the particulate. The chemical character of the SOF was significantly changed through the trap as was the biological character. The mutagenic specific activity of the SOF was generally increased through the trap but this was offset by a decrease in SOF mass emissions.
1983-02-01
Technical Paper
830553
T. J. Callahan, Thomas W. Ryan, G. B. O'Neal, R. W. Waytuloni
The increased use of diesel-powered equipment in underground mines has prompted interest in reducing their exhaust pollutants. Control of particulate emissions without substantial penalties in other emissions or fuel consumption is necessary. This paper describes test results on a prechaaber, naturally-aspirated, four-cycle diesel engine in which two different concentrations of water-in-fuel emulsions were run. The independent variables comprising the test matrix were fuel, speed, load, injection timing, injection rate, and compression ratio. The dependent variables of the experiment included particulate and gaseous emissions and engine thermal efficiency. Regression analysis was performed on the data to determine how particulate emissions were affected by fuel and engine parameters. Results of this analysis indicated that substantial reductions in particulate emissions could be obtained by utilizing water-in-fuel emulsions.
1983-02-01
Technical Paper
830544
J. D. Murrell, S. Loos, R. Heavenrich, J. Cheng, E. LeBaron
This, the eleventh in a series of Papers on EPA fuel economy trends, emphasizes the current Model Year (1983) as usual, but also gives increased emphasis to trends in vehicle technology, including catalyst and transmission subclasses. Final “CAFE”* production volumes and MPG figures have been used to update the data bases through the 1980 Model Year, and an analytic method used in the past to allocate year-to-year fleet MPG changes to specific causes, such as weight mix shifts, has been reinstituted. Conclusions are presented on the relation between fuel economy and emission standards, catalyst types, and transmission types.
1983-02-01
Technical Paper
830574
David Ganoung
Maximum fuel economy and Low exhaust emissions can exist together if a predominantly wide-open-throttle engine operating schedule is used to complement a continuously variable transmission. Moreover, the concurrently required engine re-calibration often entails less effort than the more usual fuel consumption and emission mapping procedure.
1983-02-01
Technical Paper
830585
Robert L. Chance, Ronald G. Ceselli
Eight exhaust gas condensates were evaluated for their corrosiveness towards plain carbon steel, Type 1 aluminized steel, Galvalume, and Type 409 stainless steel. Test methods included the use of anodic polarization measurements and a cyclic immersion procedure. The corrosivity of an exhaust condensate is affected by its chemistry, which in turn may he affected by variations in fuel, engine operating conditions, type of engine, and the emission control system. Condensate pH of those tested ranged from 2.3 to 9.0. Results of the corrosion tests showed that acidic condensates were generally the most corrosive, but that substantial pitting corrosion could occur with alkaline condensates.
1983-02-01
Technical Paper
830584
Joseph E. Hunter
Condensate composition was determined for 1981–82 General Motors vehicles with a) diesel engines and no converters, b) gasoline engines with oxidizing converters, c) gasoline engines with computer command control and dual bed bead or dual bed monolith converters, and d) gasoline engines with computer command control and single bed bead converters having three-way catalysts. The pH was found to range between 2.3 and 9.2 for the systems studied. Anions present in low pH condensates were sulfate, nitrate and chloride. Near neutral condensates and basic condensates also contained ammonia plus bicarbonate and carbonate anion, and had generally higher sulfate content than the acid condensates. Results are shown to be related primarily to differences resulting from the catalytic reduction of NOX and fuel sulfur content.
1983-02-01
Technical Paper
830587
Anthony J. Giovanetti, Jack A. Ekchian, John B. Heywood, Edward F. Fort
The direct injection spark-ignition engine is the only internal combustion engine with the potential to equal the efficiency of the diesel and to tolerate a wide range of fuel types and fuel qualities without deterioration of performance. However, this engine has low combustion efficiency and excessive hydrocarbon emissions when operating at light load. In this paper, potential sources of hydrocarbon emissions during light load operation are postulated and analyzed. The placement of fuel away from the primary combustion process in conjunction with a lack of secondary burnup are isolated as important hydrocarbon emissions mechanisms. Analyses show that increasing cylinder gas temperatures can improve secondary burnup of fuel which would reduce hydrocarbon emissions. Practical means to achieve this include higher compression ratio and use of ceramic parts in the combustion chamber.
1983-02-01
Technical Paper
830454
Joseph C. S. Lai, Barry Wood
A mass spectrometer has been used to study the nitrogen oxides emissions from a diesel engine equipped with two different turbochargers. Methods of accounting for interference effects from other gases in the exhaust have been described. Results compare well with those obtained by a chemiluminescent analyzer in the trend of nitric oxide emission as a function of engine speed, with the emission level reaching a maximum at where the maximum torque occurs. Discrepancy is found in the absolute levels of nitric oxide between the results of the two instruments but overall agreement is reasonable.
1983-02-01
Technical Paper
830455
K.-H. Lies, A. Postulka, H. Gring
Since about four to five years car manufacturers are concerned with measurements of particulate matter in the diesel exhaust gas and with possible measures to control and re duce these substances. This paper discusses the technical approaches to the problems of sampling and determination of the diesel particulates on a mass basis. In detail the paper includes 1) results from experiences with the instrumentation for sampling and weighing particulate matter: manual sampling set-up, automatic sampling apparatus, filter holder., filter material, and microbalance; 2) results of the investigation of the main test parameters: sample flow rate, background particulate level, filter conditioning and efficiency. Further, a specific area of concern was the uncertainty of the measurements especially the variability and correlation of test results.
1983-02-01
Technical Paper
830183
Daniel H. Gerke
A system has been developed that provides real-time measurement of heavy-duty diesel engine particulates emitted during the EPA transient emission test cycle. This is accomplished by measuring the opacity of the exhaust/air mixture in an EPA type dilution tunnel with a light extinction opacity meter. Simultaneously, the temperature in the dilution tunnel is measured, and the ratio of the dilution tunnel temperature to a standard temperature is used to correct the opacity signal to standard conditions. The outstanding features of the system are that it produces a continuous record of when particulates were generated during the 20-minute transient cycle and that particulate cycle results are available immediately upon completion of the transient cycle without the requirement of conditioning and weighing filters. Results to date indicate correlation of the opacity-particulate monitor measured particulates to gravimetrically determined particulates to be within 10% for specific engines.
1983-02-01
Technical Paper
830618
Harald Koch, Dietrich Meyerdierks, John Golden
A complete new emission control system has been designed for Volkswagen four cylinder inline carburetor power plant in model year 1982. This paper will describe the main components of the mixture formation and emission control system consisting basicly of a new carburetor and dual bed catalytic converter. The paper also shows the development results in the area of emission and fuel consumption.
1983-02-01
Technical Paper
830087
Polat Öser, Ulrich Thorns
Basic investigations of the particulate control system projects for VW and Audi diesel engines are summarized. A screening test procedure to evaluate the particulate concepts is developed and the significant assessment criteria are defined. The storage and regeneration characteristics as well as balance temperatures, introduced with this paper, are applied to various uncoated and catalytically coated filters. This paper discusses also the parameter studies for uncoated filters. A survey of regeneration techniques and individual regeneration methods is given with energy consideration and fuel consumption effects. After establishing the current stage, the priorities for further technical development work are set and the problem areas throughout the particulate control field are demonstrated. Cost-benefit in applicability for production use is considered.
1983-02-01
Technical Paper
830646
Henry Richard, Deighton Simpson, Barbara Mary Andon, William George Thilly, Joe Merrill Rife
Particulates were collected from the exhaust of a single cylinder diesel engine at different speeds and fuel-air equivalence ratios. The filters were rated to capture 99.99% of all particulates >0.3 microns in diameter. Samples were taken at 1500 RPM and equivalence ratios varying from about 0.2 to 0.7, and at an equivalence ratio of about 0.3 and engine speeds varying from 1000 to 2500 RPM. A base point with an equivalence ratio of 0.3 with an engine speed of 1500 RPM was repeated several times to establish the expected test variation of the particulate data. The particulate properties investigated were the total mass of particulate produced per mass of fuel burned, the mass fraction of extractable organic material in the sample, and the mutagenic potency of the extract as measured by a bacterial bioassay. Variation in fuel-air ratio (engine load) affected the particulate and extractable organic production much more than variations in engine speed.
1983-02-01
Technical Paper
830707
Weldon E. Garrelts
Six, one hundred eighty horsepower aircraft piston engines have been operated through their normal overhaul life using three different ashless dispersant multi-viscosity aircraft oils. Two of these oils achieved their multi-viscosity characteristics by utilizing some synthetic base stock while the third utilized additional viscosity-index (V-I) improver. The performance of these three oils was compared with that of a conventional, single-grade AD oil in six identical control aircraft engines. The results of this test indicates that multi-viscosity oils provide improved cold-weather starting, less consumption, and comparable wear rates to the six control engines.
1983-02-01
Technical Paper
830081
E. Koberstein, H.-D. Pletka, H. Völker
An engine test unit for the evaluation of Diesel exhaust filters with analytical equipment to measure particulates, oxygen, hydrocarbon, carbon monoxide, nitrogenoxides concentrations, temperature and pressure trends is described as well as the test procedures presently applied. Engine test results with different types of Diesel particulate filters -non activated and catalytically activated - up to 400 hrs. operation time are presented. With base metal catalysts, reductions in “soot”-ignition temperatures of about 100 °C could be attained under optimal conditions. A correlation between oxygen concentration in the exhaust gas and the “soot”-ignition temperature is demonstrated. Combined catalytic systems (precious metal and base metal catalysts) permitted hydrocarbon and carbon monoxide conversions up to 90 % - including a decrease in odour intensity - in addition to particulate reduction.
1983-02-01
Technical Paper
830078
Noboru Higuchi, Shigeru Mochida, Masaru Kojima
Ceramic honeycomb filters performing diesel particulate trapping require regeneration by burning the subsequently accumulated particulate. During this regeneration, thermal failure occurs in some conditions. For developing a highly reliable system with this method, it is necessary to clarify the effects of various factors on the failure to optimize the regeneration conditions. This paper gives the results of an experiment, employing a burner method, of the effect on the damage of regeneration conditions of gas temperature, oxygen concentration, gas flow rate and amount of accumulated particulate, and discusses the regeneration conditions under which the filter is safely operated.
1983-02-01
Technical Paper
830435
H.C. Watson, E.E. Milkins, M.O. Preston, C. Chittleborough, B. Alimoradian
The models presented for predicting fuel consumption and emissions for vehicles driven on the road provide the means for averaging and storing results obtained from vehicle tests usually carried out at an emissions test facility to standard and non-standard-drive schedules. For hot start fuel usage and emissions rates the models, in descending order of temporal or spatial resolving capability, include: transient engine mapping (a new model), steady state engine mapping, vehicle mapping, power demand, modal or elemental, lumped parameter (PKE-v) and travel time variants. The engine mapping model is shown to be able to predict instantaneous on-road fuel consumption with good precision (±3ml) for one vehicle over a selected 3.3 km stretch of road. Its emissions rate predicting ability is less satisfactory. When link-by-link fuel is needed the 6 coefficient PKE-v model performs well (R = 0.994).
1983-02-01
Technical Paper
830167
W. J. Kaiser, E. M. Logothetis
This paper discusses the properties of EGO sensors based on thick TiO2 films. These devices are fabricated by depositing a TiO2 film on an insulating or conducting substrate. In addition to being inherently inexpensive, planar techniques provide flexibility in the fabrication of multicomponent structures incorporating temperature compensation and heating elements. Furthermore, TiO2 film sensors are found to possess faster transient response than available ZrO2 and ceramic TiO2 sensors. Results of engine studies of the properties of these new TiO2sensors will be presented and discussed.
1983-02-01
Technical Paper
830245
Jamil Ghojel, John C. Hilliard, John A. Levendis
The purpose of this study was to determine the effect of the partial pressure of O2 in the intake charge of an I.D.I. diesel engine on the various operating parameters and the exhaust emissions. The oxygen content in the intake was varied between 21% and 40% by volume. Engine performance and emissions were evaluated at constant engine speed and injection timing while fueling was varied. The research revealed that enriching the intake air with oxygen led to a large decrease in ignition delay and reduced combustion noise. The fuel economy, the power output and the exhaust temperature remained almost constant. HC and CO emissions decreased and smoke levels dropped substantially, while NOX emissions increased pro-rata with the O2 added. Theoretical analysis using the Zel’dovich kinetics showed that nitric oxide emissions are sensitive to “mean NO-formation temperature” and the combustion duration associated with this temperature, and, to a lesser extent, the atomic oxygen concentration.
1983-02-01
Technical Paper
830179
Michael P. Walsh
This study builds upon the National Academy of Sciences study in the rapidly changing area of diesel particulate cost-benefit analysis and updates it where appropriate based on new data or analysis. It does not generate new information but merely reviews and analyzes existing data. The body of the paper a) explains the basis for estimating the various costs, b) describes a computer model to relate the costs to the benefits, and c) presents the results of the analysis.
1983-02-01
Technical Paper
830564
Robert L Henderson, Russell L. Smith, William J. Burger, Seymour D. Stern
This paper addresses the relationships between visibility from a vehicle and probability of accident involvement. It defines and discusses direct and indirect visibility in terms of both quantity (extent of the field of view available to the driver), and quality (extent to which the available field of view is degraded by adverse weather or other factors). Relevant vehicle, driver, and environmental characteristics are identified, and their frequency of occurrence and relationship to accidents (or pertinent proxies) discussed whenever such information is available. The bulk of the report is devoted to reviewing, summarizing, and integrating the large body of data concerning visibility, including engineering analyses and other analytical studies, as well as experimental data from laboratory, simulation and field studies.
1983-02-01
Technical Paper
830566
Robert L. Henderson, Kenneth Ziedman, William J. Burger, Kevin E. Cavey
This paper addresses the relationship between vehicle conspicuity and probability of accident involvement. As used here, conspicuity refers not only to the “noticeability” of the vehicle, but also to the recognizability of the vehicle and its behavior relative to the observer. All classes of vehicles are considered during both day and night driving on all types of roadways. Relevant vehicle, driver, and environmental characteristics are identified, and their frequency of occurrence and relationship to accidents (or pertinent proxies) discussed whenever such information is available. The bulk of the report is devoted to reviewing, summarizing, and integrating the available body of data concerning vehicle conspicuity, including engineering analyses and other analytic studies, as well as experimental data from laboratory, simulation and field studies.
1982-10-01
Technical Paper
821565
Roy A. Lonsbrough
Particulate contamination in a hydraulic system must be measured to monitor and take corrective action to maintain the desired cleanliness level. Counting methods are reviewed, and the use of Automatic Particle Counters (APCs) is presented as the preferred method. The importance of the calibration method for APCs is stressed, and comparisons of the procedures by American National Standards Institute (ANSI), American Society for Testing and Materials (ASTM), and Society of Automotive Engineers (SAE) are presented. The procedures of ARP 1192A are presented in detail as the microbead technique for calibration. Patents developed to aid in carrying out the procedures are cited. Actions being taken to confirm the procedures of ARP 1192A are presented.
HISTORICAL
1982-06-01
Standard
J312_198206
This SAE Recommended Practice summarizes the composition of modern automotive gasolines, the significance of their physical and chemical characteristics, and the pertinent test methods for defining or evaluating these properties.
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