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1972-02-01
Technical Paper
720254
Paul H. Schweitzer
A proposed set of modifications, which, in combination with a mixture-Optimizer, enables a spark-ignition engine to accept air-fuel mixtures as lean as 22 - 23-1/2:1 without impairment of drivability, will permit the simultaneous reduction of all pollutant exhaust emissions, HC, CO, and NOx, to a very low level. Under such circumstances, the true best economy mixture largely coincides with the mixture ratio that minimizes the exhaust emissions. The mixture-Optimizer is a feedback type of electronic control device which automatically selects for a carburetor or fuel injection system the air-fuel ratio that yields the minimum fuel consumption for any given power output. For all driving conditions, other than idling and coasting, the minimum fuel consumption occurs at mixture ratios close to the borderline misfire limit. Therefore the mixture-Optimizer, by seeking these mixture ratios, tends to reduce all pollutant exhaust emissions that are under legal control.
1972-02-01
Technical Paper
720253
John M. Pierrard, Richard A. Crane
Laboratory and field tests were conducted to determine how changes in some gasoline compositional factors might affect atmospheric visibility and soiling caused by exhaust particulate matter emitted from late model automobiles. In the laboratory tests, measurements of light scattering, soiling index, and mass emission rates of air-suspendible particles were made on diluted exhaust from cars driven on a programmed chassis dynamometer. These tests showed that light scattering, and also soiling, were increased by increasing the aromatic content, removing lead antiknocks, or increasing the combined amounts of sulfur and phosphorus in gasoline. Field tests in a turnpike tunnel used two 4-car fleets operating on leaded and unleaded premium gasoline of high and average aromatic content. The air in the tunnel sampled during the tests with the cars using the unleaded gasolines soiled the filters 57% more than the air sampled during the tests with the cars using the leaded gasolines.
1972-02-01
Technical Paper
720251
Eric E. Wigg, Raymond J. Campion, Wm. Lewis Petersen
Fuel-exhaust compositional relationships are derived for exhaust hydrocarbons and aldehydes using data obtained with 18 full-boiling-range gasolines used as fuel in a late model vehicle. The agreement found between the data from the present work and those obtained by others in similar studies indicates that the relationships should be sufficiently general to apply to a large segment of the current vehicle population. The present data indicate that aromatic hydrocarbon and aromatic aldehyde emissions are linearly related to fuel aromatic content, while exhaust olefin and aliphatic aldehyde emissions show an inverse relationship. Regression analysis of the aromatic hydrocarbon and aromatic aldehyde data, expressed as a function of fuel aromaticity, gives fuel aromatic coefficients of 0.49 and 0.41 for the hydrocarbon and aldehyde expressions, respectively.
1972-02-01
Technical Paper
720264
James M. Miller
The Occupational Health and Safety Act of 1970 may have much importance to the truck cab designer. The levels of noise, heat, and carbon monoxide to which the truck operator is exposed may be a health and safety hazard. While current standards for these hazards have not been directly applied to commercial carriers, it is predicted that they will be in the near future. Some current research in the noise and carbon monoxide areas in particular is cited; legal standards for these are projected for the designer's use. The inclusion of air conditioning as standard equipment in large trucks may be a realistic way to meet new standards.
1972-02-01
Technical Paper
720263
Charles D. Storrs, Otto H. Lindemann
The Motor Vehicle Safety Standard 302 becomes effective September 1, 1972, establishing a 4 ipm horizontal burn rate for materials used in the passenger compartment of motor vehicles. Limitations of the standard are touched upon. Conventional approaches to impart fire retardance to vinyls,polyolefins, urethane foams, ABS, polyester, and carpeting are reviewed. Potential problems associated with each of the approaches include fogging, dripping, staining, low-temperature flexibility, durability, effect on physical properties, and cost.
1972-02-01
Technical Paper
720238
E. S. Wright, W. R. Davison, L. E. Greenwald
The feasibility of a simple-cycle gas turbine engine for automobiles is analyzed by means of comparison with Otto-cycle engines for automobiles. Applicable technology is reviewed with emphasis on centrifugal compressor technology, which has demonstrated pressure ratios of better than 10:1. The design point of a simple-cycle 150 hp automobile engine based on these components is presented, together with estimated torque and fuel-flow characteristics for the entire range of possible engine performance, derived from engine-cycle analysis programs. The results of a vehicle performance computer program designed to evaluate candidates for this application include time/speed/distance performance estimates for maximum acceleration as well as fuel economy and emissions estimates for pertinent driving cycles. Summaries of manufacturing cost estimates are presented for several candidate gas turbine engines.
1972-02-01
Technical Paper
720237
C. A. Amann, W. R. Wade, M. K. Yu
The intent of this paper is to put into proper perspective the relationships among the vehicle, the thermodynamic cycle, and the combustion process as they relate to exhaust emissions from a gas turbine-powered passenger car. The influence of such factors as car size, installed power, regeneration, and other cycle variables on level road load fuel economy, and on the production of oxides of nitrogen and carbon monoxide, are examined. In limited checks against experimental data, the mathematical model of the combustor used in this study has proved to be a reliable indicator of emission trends. The calculated emission levels are not final, however, with deficiencies subject to improvement as new combustor concepts are developed.
1972-02-01
Technical Paper
720468
Charles Jones
This paper summarizes the highlights of developments of the rotating combustion (RC) engine at Curtiss-Wright Corp. in each of several principal areas; speculates on remaining directions, both within and without the framework of previous explorations; and briefly describes germane technical features of the engines used in commercial applications of other licensees. At the same time an attempt has been made to span gaps left by previous papers or publications and to expand material considered proprietary earlier. Design features, testing, and ramifications of the RC1-60 rig engine are examined in detail. The application of the fundamentals and principles of the RC engine to automotive, air-craft, and small, air-cooled engines is also described.
1972-02-01
Technical Paper
720460
A. J. Fritsch
Industrial practices can cause consumer confusion. The failure to communicate between the highest levels of automotive and petroleum companies provides an example. Gasoline is taken for granted by the driving public. It is extremely toxic and its emission products are a major contributing factor to air pollution. Engineers know how automotive and gasoline problems are interlocked. The Clean Air Act has forced scientists and engineers to cooperate. Technological solutions and cleanup timetables are insurmountable only when this collaboration is missing. The substantiation of gasoline advertisements, trade secrecy, standardization, and lead consumption are also covered in this paper. To preserve a safe and pollution-free environment, the scientist and the engineer both have a duty to anticipate toxic and unsafe products and company practices.
1972-02-01
Technical Paper
720461
Sidney B. Tuwiner
MECAR (Metropolitan Engineers Council on Air Resources), organized in 1965 to represent the engineering profession through its various societies in the New York metropolitan area, has four objectives: 1. To advise on standards and formulation of laws to improve air quality. 2. To serve law enforcement agencies in an advisory capacity. 3. To alert city, county, regional authorities, and the general public to pollution problems. 4. To inculcate within the engineering profession the need to cope with the sociotechnical problem. The group attempts to maintain consistency of direction of policy in matters pertaining to air quality in metropolitan areas.
1972-02-01
Technical Paper
720462
M. R. J. Wyllie
The premise of this paper is that many of the problems facing society are technological at heart, and can be solved only by the application of better technology by technologists. Further, it is the duty of technological organizations to present and publicize impartial, balanced advice to the public and government as to the best courses of action to pursue. The author illustrates his hypothesis by taking three areas as examples, namely, the population explosion, the eutrophication of lakes, and automobile emissions. For each, he examines currently disseminated information, points up inaccuracies in much of this information, and suggests avenues to be explored in working for solutions.
1972-02-01
Technical Paper
720455
J. F. Cassidy
Exhaust emission tests run on an engine dynamometer are compared with those run on a chassis dynamometer. The worst case average difference between the chassis and engine dynamometer mass emissions, obtained over a period of 6 months, was less than 7%. The elimination of the driver, vehicle, and chassis dynamometer yielded significant improvement in test reproducibility with respect to carbon monoxide and oxides of nitrogen. A digital computer was used to control speed and throttle position of the engine dynamometer experiments. No transmission was used. The computer and engine dynamometer duplicated transient effects of transmission, vehicle, and chassis dynamometer.
1972-02-01
Technical Paper
720483
Yasuo Kaneko, Yuhiko Kiyota
During the past four years, Mitsubishi Motors Corporation has been active in the design and development of catalytic converter systems in the IIEC Program. Experience indicates that an effective dual catalytic converter, consisting of a NOx catalyst and a HC/CO catalyst, is indispensable to achieve the stringent IIEC targets, established on the basis of 1976 Federal Standards. However, there still remains a major difficulty of meeting the NOx target since NO is regenerated in the HC/CO catalyst in the dual converter system. This paper describes our major efforts in seeking a breakthrough to control the NOx emission, and covers some noteworthy findings on transient NO concentrations at the inlet and outlet of HC/CO converter in an experimental dual converter.
1972-02-01
Technical Paper
720482
P. Öser, D. H. Pundt, W. Buttergeit
A test procedure to determine the conversion performance of oxidation and reduction catalysts for the treatment of automotive engine exhaust gases is described. The variable parameters are the air/fuel ratio, the secondary air quantity and the space velocity. The results are recorded in diagrams which permit the selection of optimal catalysts with reference to the conversion and which also form the basis for the lay-out of the necessary devices for controlling air/fuel ratio and secondary air. Characteristic results with noble metal catalysts on monolithic supports and pelleted base metal catalysts are shown.
1972-02-01
Technical Paper
720485
Carlo Pollone
The work reported has been done in the last year as part of Fiat's collaboration with the Inter-Industry Emission Control Program. Emission results obtained on two concept cars are shown, including respectively: thermal reactor, exhaust gas recirculation (EGR), HC/CO catalytic converter, and NOx and HC/CO catalytic converters. Work is also reported on screening of materials for thermal reactors and catalysts.
1972-02-01
Technical Paper
720484
H. Kuroda, Y. Nakajima, Y. Hayashi, K. Sugihara
The Inter-Industry Emission Control (IIEC) Program included the thermal reactor as one of the effective ways of oxidizing HC and CO in the exhaust system. However, this was accompanied by very substantial fuel economy penalties, especially in the case of small engine-low emission concept vehicles. Starting with a new concept aimed at obtaining the HC/CO oxidizing trigger temperature in the thermal reactor by modifying engine settings, the authors arrived at an economical technique of matching the thermal reactor to the engine.
1972-02-01
Technical Paper
720479
P. W. Snyder, W. A. Stover, H. G. Lassen
The 1975 federal CVS test procedure and emission standards have placed a heavy emphasis on minimizing the time required after engine start up to begin converting exhaust emissions. Four major improvements in catalytic HC/CO converters have been made in the past year to reduce catalyst ignition time: 1. Use of low thermal capacity monolithic catalyst supports. 2. Locating converter after thermal reactor and/or closer to the exhaust manifold. 3. Development of catalysts with superior stability to long exposure at high temperatures. 4. Development of catalysts with improved low temperature activity. Small laboratory samples of potential HC/CO oxidation catalysts were screened for activity in a “laboratory simulated cold-start” test with exhaust from a 2-cyl engine. Several improved catalyst candidates were evaluated in a full-size converter “cold-start” test with exhaust from a 351 in3 engine.
1972-02-01
Technical Paper
720480
G. H. Meguerian, F. W. Rakowsky, E. H. Hirschberg, C. R. Lang, D. N. Schock
IIEC efforts to develop NOx catalysts with improved durability have continued. Properties of several nickel oxide catalysts on pelleted, monolithic ceramic, and metallic supports are discussed and the engineering requirements for their effective use are defined. Some promoted nickel oxide, pelleted catalysts show good low-temperature activity, and produce minimal amounts of ammonia but are strongly deactivated by sulfur in the feed gas. Monolithic and metallic catalysts, on the other hand, although not active at temperatures below 1000 F, are very active at higher temperatures where deactivation by sulfur and ammonia formation are not troublesome.
1972-02-01
Technical Paper
720498
F. L. Voelz, E. C. Coleman, J. S. Segal, B. G. Gower
The results of a nationwide automobile exhaust emission survey conducted in 1971 are presented and compared to data obtained from a 1970 survey. Average hydrocarbon and carbon monoxide emissions are given for engine speeds of idle and 2500 rpm. Vehicle distribution curves for hydrocarbon and carbon monoxide emissions are shown for the 1971 data for selected year groups based on emission control devices. Comparison of the distribution curves obtained from the 1971 and 1970 data show that “deterioration” (increased emissions) occurred at both idle and 2500 rpm in the one year period. The effects of carburetor adjustments on idle emissions are compared for the 1971 and 1970 data.
1972-02-01
Technical Paper
720497
Vincent S. Darago, Charles M. McCuen
The Urban Vehicle Design Competition was inspired by the success of the Clean Air Car Race and the Great Electric Car Race. The academic community recognized the tremendous educational value of these events, and encouraged development of UVDC from its inception. The project was designed by engineering students to benefit students throughout North America. The rules of the competition include technical paper requirements that make the competition extremely attractive to professors who wish to build a course around this theme. The response of more than 2000 engineering students at 80 universities throughout the United States and Canada has indicated the success of the structure of the competition. The first major objective of the UVDC project has been met. Ninety-three teams throughout the country entered the UVDC design portion of the contest. The second portion of the project is the prototype contest of August 1972.
1972-02-01
Technical Paper
720500
R. P. Doelling, A. F. Gerber, P. M. Kerschner, M. S. Rakow, F. H. Robinson
An investigation was undertaken to determine if gasoline additives could effect a reduction in exhaust HC emissions. Of the multitude of compounds studied, two were found to reduce the increase in HC emissions associated with the accumulation of lead-derived combustion chamber deposits by approximately 50%. A practical combination of these compounds was evaluated in a fleet test which confirmed laboratory engine results. Studies were also conducted in laboratory engines and fleet vehicles to determine the effect of fuel lead level upon this additive's effectiveness and the activity of the additive upon established lead-derived combustion chamber deposits. Results obtained from these programs indicated that the additive would function with fuel lead levels from 1/2-3 g/gal, but that it was not capable of modifying established deposits. A rationale for the observed effect is presented.
1972-02-01
Technical Paper
720488
R. M. Campau, A. Stefan, E. E. Hancock
Recent vehicle durability experience with low emission concept hardware systems is described. The low-emission concept systems discussed include: thermal reactor only, a combined thermal reactor and HC/CO monolithic catalyst system, and a system combining low thermal inertia exhaust manifolds with dual-bed (NOx and HC/CO) catalytic converters. Problems shown to influence either emission performance or vehicle function during both atypical and normal vehicle operation include: the melting of monolithic structures used to support both the NOx and the HC/CO catalytic promoters, the deleterious effect of the sulfur content of gasoline on the performance of pelleted NOx catalysts, and the loss of emission control with malfunctioning engine components. Vehicle fuel economy and performance losses with these types of systems is documented. Current redesign efforts on these low emission concept vehicle systems in an attempt to overcome the durability problems are described.
1972-02-01
Technical Paper
720486
K. Tanaka, M. Akutagawa, K. Ito, Y. Higashi, K. Kobayashi
This paper describes the extensive effort and progress made by the Toyo Kogyo Company in developing emission control systems applicable to small vehicles with small displacement reciprocating engines, in order to achieve the very stringent targets established by the IIEC program. Three concept emission package systems have been selected as showing promise to achieve the targets, and these packages have been under evaluation for emission performance and durability in the total vehicle systems, which were experimentally built. These package systems incorporate component systems such as thermal reactors, EGR, catalytic converters, and other subcomponents to assist these main component systems. Despite the effort made to date, none of these package systems have reached the stage of satisfying the HC/CO targets over extended vehicle mileage, or the NOx target, even at zero vehicle miles. The durability of these package systems has been revealed as unsatisfactory.
1972-02-01
Technical Paper
720487
T. Inoue, K. Goto, K. Matsumoto
The status of Toyota's development of low emission concept packages- 1. NOx and HC/CO Catalytic Converter and EGR, 2. Thermal Reactor, NOx and HC/CO Catalytic Converter and EGR and their components is described. Variations of thermal reactor design, performance and durability characteristics are discussed. Above the throttle valve entry EGR has been found to have desirable flow characteristics with a simple control system. EGR rate over 15% brings about unacceptably poor driveability and fuel economy with smaller vehicles. Many types of catalytic converters for pelleted catalysts have been designed and examined for their performance and durability. A down-flow type converter has relatively good flow distribution and warm-up characteristics. As for HC and CO, a few prototype vehicles have met the 1975 Federal Regulation at low mileage, but the 1976 regulation for NOx of 0.4 gm.
1972-02-01
Technical Paper
720520
John L. Harned
Performance of packed bed type catalytic converters in controlling hydrocarbon (HC)-carbon monoxide (CO) mass emissions is investigated using a one-dimensional plug flow math model. Converter operation is explained, and the effects that some gas stream conditions and basic parameter values have on converter emission control performance during warmup are evaluated. It is shown that total mass emissions passed by the converter during warmup can be minimized by maintaining gas mass flow and HC-CO concentrations at low values. Converter warmup performance is highly sensitive to changes in bead diameter and catalyst kinetics, but it is relatively insensitive to changes in bed area/length ratio and bed void fraction. New information is presented dealing with the modeling of platinum kinetics, bead temperature stability, and mass and heat transfer j-factors for packed beds.
1972-02-01
Technical Paper
720518
C. Henault
Because of low nitrogen oxide emissions, a version of the Renault R17 TS equipped with a high-performance engine was selected for the American market. This paper discusses problems encountered in adapting a Bosch electronic fuel injection system to a 1600 cm3 engine to meet American standards up to 1974. The principal problems solved were those posed by intermediary operating speeds. This study also gives an idea of the pollution limits which can be obtained with an injection system which incorporates various important adjustment factors. Engine specifications are presented, as are decriptions of the electric regulation, electric and pneumatic cold-start, and fuel feeding circuits. The various modifications to the engine are also described.
1972-02-01
Technical Paper
720519
A. L. Thompson
In 1972 models for sale in California, Buick first employed programmed-metered exhaust gas dilution of the engine intake charge as the major means of reducing Oxides of Nitrogen (NOx) emission levels. With more stringent NOx emission standards applicable nationally to 1973 light duty vehicles, it is probable that similar systems will be more widely used. The major considerations in the decision to use this means of reducing NOx emissions, the design details of the total system, and the field experience to date is discussed. The author concludes with some thought on the limit of usefulness of Exhaust Gas Recirculation for NOx reduction, and further refinements needed to approach that limit.
1972-02-01
Technical Paper
720511
John C. Chipman, John Y. Chao, Ray M. Ingels, Roy G. Jewell, Wendell F. Deeter
The California Air Resources Board conducted an extensive field test program to evaluate a vehicle exhaust recirculation system for control of oxides of nitrogen. The system utilized hot exhaust gases from the crossover and included certain modifications to the carburetion, choke, and crank case ventilation system. It was tested on two fleets of automobiles equipped wtih California approved HC and CO emission control devices. The test program involved periodic measurements of exhaust emissions and fuel consumption. The effect of the system on vehicle drivability, engine deposits, wear, and oil deterioration was also studied. The Atlantic Richfield Company, under contract to the Air Resources Board, equipped the vehicles with the recirculation system and performed the final engine inspection.
1972-02-01
Technical Paper
720510
E. N. Cantwell, R. A. Hoffman, I. T. Rosenlund, S. W. Ross
Exhaust manifold thermal reactors, exhaust gas recirculation, exhaust particulate trapping systems, and appropriate engine adjustments have been combined to produce total emission control systems which reduce all gaseous and exhaust particulate emissions from passenger vehicles. The first generation system was developed to meet the former United States and State of California emission standards for 1975. Field service tests demonstrated that the emission standards were met, but unexpected operational problems were encountered. Solutions to these problems have been found. Second generation total emission control systems are being developed in an attempt to meet the current United States emission standards for 1975 - 1976. These systems in their present state of development produce very low exhaust emission levels; the hydrocarbons are well below the standards and the carbon monoxide and nitrogen oxide levels are quite close to the 1975 - 1976 standards.
1972-02-01
Technical Paper
720509
James G. Hansel
A wide range of air/fuel ratios and exhaust gas recycle rates were examined in an automotive test engine for the purpose of reducing NOx emissions to low levels. A minimum NOx level of 0.4 g/mile on the 1972 Federal Test Procedure was obtained at a rich A/F of 12 and a recycle rate of 25%. With this combination, the fuel consumption increased approximately 15% and the wide open throttle (WOT) power decreased about 30%. Combustion in the cylinders was good and the vehicle operated smoothly. Comparable results were not obtained with lean mixtures. The results of this study do not establish the feasibility of meeting the 1976 NOx standard with the rich mixture, high recycle technique. Further, the increased CO and HC emissions would have to be controlled by exhaust gas treatment.
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