Criteria

Display:

Results

Viewing 22051 to 22080 of 22470
1967-02-01
Technical Paper
670494
Louis J. Papa
Several methods for determining hydrocarbons in automotive exhaust are presented and discussed. These include: nondispersive infrared, ultraviolet, flame-ionization detection, and gas chromatography. A gas chromatographic method is presented for determining individual hydrocarbon components in automotive exhaust. The method has thus far detected over 200 hydrocarbons of all classes in exhaust. A technique for collecting the exhaust sample in small plastic bags is described along with a brief study on the selection of suitable bag material. Techniques for sampling, calibration, and standardization are also discussed. Applications of the method are presented along with a discussion of the results.
1967-02-01
Technical Paper
670495
Henry K. Newhall
The control of nitrogen oxides by exhaust recirculation has been evaluated theoretically by digital computer simulation of the engine cycle. Nitric oxide emission, power output, and fuel consumption have been considered. Preliminary results indicate that effectiveness of the recirculation method of nitric oxide control can be accounted for by the attendant shift in the peak temperature chemical equilibrium species distribution. The analysis reveals that nitric oxide reduction is highly dependent on fuel-air ratio, and somewhat less dependent on the temperature of recycled exhaust gases.
1967-02-01
Technical Paper
670482
T. A. Huls, H. A. Nickol
The influence of engine variables on the concentration of oxides of nitrogen present in the exhaust of a multicylinder engine was studied. The concentrations of nitric oxide (NO) were measured with either a mass spectrometer or a non-dispersive infrared analyzer. The NO concentration was low for rich operation (deficient in oxygen) and increased with air-fuel ratio to a peak value at ratios slightly leaner than stoichiometric proportions. A further increase in air-fuel ratio resulted in reduced NO concentrations. Advanced spark timing, decreased manifold vacuum, increased coolant temperature and combustion chamber deposit buildup were also found to increase exhaust NO concentration. These results support either directly or indirectly the hypothesis that exhaust NO concentration is primarily a result of the peak combustion gas temperature and the available oxygen. The NO concentration of the exhaust from an individual cylinder is a function of the air-fuel ratio of the charge that the individual cylinder receives.
1967-02-01
Technical Paper
670485
J. H. Jones, J. C. Gagliardi
The effects of air-fuel mixture quality and cylinder-to-cylinder air-fuel distribution on exhaust emissions have been determined on two engine-vehicle combinations. California Motor Vehicle Pollution Control Board (CMVPCB) test cycle emissions were measured on vehicles using a pre-mixed and pre-heated air-fuel charge supplied by a steam jacketed, nine cubic foot vaporization tank. The vaporization tank provided a near constant air-fuel mixture ratio for all operating modes of the 7-mode CMVPCB test cycle. The two vehicles were evaluated at nominal air-fuel ratios of 14:1, 16:1 and 18:1. Cylinder-to-cylinder air-fuel distribution during the transient operation of the 7-mode CMVPCB test cycle was measured on a 200-CID six cylinder and a 289-CID eight cylinder engine. The procedure employed was to record the total carbon emissions (CO + CO2 + CH4 equivalent) for each cylinder during successive test cycles. Distribution measurements thus established were found to be repeatable within ± 0.40 air-fuel ratios.
1967-02-01
Technical Paper
670484
G. Lawrence, J. Buttivant, C. G. O'Neill
Abstract A carburetor adapted to exploit the control of exhaust emissions through consistency of metering and mixture quality, particularly in conjunction with a dual bore inlet manifold, is discussed against the background problems faced by the European motor industry. The development and incidental research data which determined the design are followed by a description of production and quality assurance techniques, with special reference to the evolution of automatic flow testing apparatus.
1967-02-01
Technical Paper
670486
V. M. Exner
Abstract The recently issued Federal Motor Standard on glare reduction does not pose a problem to the automobile stylist. However, as this standard is expanded it may call for greater restrictions on interior panels and metal components in the driver's view. These future requirements may well call for greater ingenuity on the part of the stylist and for new uses of materials. The author believes the stylist will meet the challenge.
1967-02-01
Technical Paper
670611
Gerald Coren, William Cotliar, David Conroe
Ingredients necessary for studying the effects of environmental interactions are presented. A technique for quantitatively predicting the effects of combined environments upon components was developed and applied to test data obtained under controlled conditions. The synergistic effects were equalized as to exposure time and the number of environmental encounters. The data was then statistically analyzed with the following conclusions: 1. Combined environments produce a synergistic effect which acts to reduce the over-all stress severity imposed upon components by the individual environments. 2. The length of time parts are exposed to a combined environment is more critical to component life than the number of encounters with that environment. 3. Combined environments appear to produce the same effect upon a given component irrespective of the environments concerned in the combination. 4. Different components are affected in different ways by a given combined environment.
1967-02-01
Technical Paper
670659
Paul H. Zorger
During the 5th Reliability and Maintainability Symposium, the status of Reliability Education in the United States was discussed in detail. One paper discussed the status of reliability education in colleges and universities; another, the specific curriculum, another, seminars, institutes, etc., another the needs, and, finally - the challenges which must be met for reliability to survive as a professional discipline. This paper continues the discussion of the subject of reliability education. It discusses the practical application of reliability, the need, the personnel, the objectives, and the probability of achieving such objectives. The author specifically discusses the probability of achieving reliability objectives from the standpoint of personnel qualifications, recognition of these qualifications, and the specific type of knowledge required of reliability personnel, if objectives and some level or standard of acceptable competence are to be achieved. Another objective is the problem of communicating the words “reliability” and “maintainability” to a greater portion of the population.
1967-02-01
Technical Paper
670657
R. E. Killion
Standardization is a significant factor in achieving cost reduction in design, manufacturing, and field operations. In addition, it contributes to the enhancement of reliability and maintainability. In spite of these advantages it has failed to achieve full acceptance and support. Greater acceptance and support can be realized with a better understanding of the advantages and disadvantages of standardization. It is within the power of the user of standards to minimize some of the faults that presently exist and thus more fully realize the benefits of standardization.
1967-02-01
Technical Paper
670688
Ronald E. Kruse, Donald M. Hill
This paper presents an analysis and interpretation by the U. S. Public Health Service of the data obtained from a separate contract program to determine representative emission levels for imported, domestic, and total compact populations as compared to those for standard cars. To accomplish this purpose, the concentrations and mass levels of emissions of hydrocarbons, carbon monoxide, and oxides of nitrogen were measured for a variety of imported and domestic compact cars during operation on the road and on achassis dynamometer (California 7-mode cycle, hot start).
1967-02-01
Technical Paper
670687
Shoichiro Toyoda, Keitaro Nakajima, Tadahide Toda
Abstract This paper deals with some fundamental research on control of exhaust emissions from automotive engines, with particular reference to the Toyota manifold air injection system developed for the 1968 Toyota vehicle model. The influence of engine variables on exhaust emissions has been investigated under various operating conditions, such as idling, deceleration, and road load. Although some design aids involving engine modification for emission control were devised, the limited time schedule afforded for the necessary development work led to the adoption of a manifold air injection system for the 1968 Toyota model. Its characteristic features and some technical problems experienced during development are described in this paper.
1967-02-01
Technical Paper
670689
Miles L Brubacher, Eric P. Grant
Emission tests on 739 cars (1966 and 1967 models) equipped with exhaust controls in public use confirm that the vehicle manufacturers have done a good job of designing cars with low emissions. However, field data on emissions higher than proving ground results, and deterioration of emissions with mileage, indicate that much more effort is needed with regard to proper engine adjustments and quality control on the production line as well as better servicing of the engines in the field. Continued effective emission control after initial sale of the new car is the responsibility of the states.
1967-02-01
Technical Paper
670165
John A. Westveer
Current legally specified test procedures for measuring hydrocarbon and carbon monoxide concentrations in vehicle exhaust gases contain intrinsic test variables which significantly affect test results. These variables constantly hamper efforts to correlate test data generated at one or more exhaust emission test facilities. This paper will provide a general description of some of the more prominent test variables such as vehicle repeatability, test driver repeatability, instability of calibrating gases and changing ambient test conditions. In addition to describing test variables and their effects, the paper will describe the success of various measures which were undertaken to reduce or eliminate the influence of some of the variables on test repeatability and facility correlation.
1967-02-01
Technical Paper
670164
R. M. Cobb, F. Perna
This paper discusses data reduction systems for use at exhaust emission test facilities. An investigation of ways and means of automatically reducing the large volumes of data generated in exhaust emission testing is discussed. Four distinct data reduction methods were considered and evaluated. The investigation resulted in the specification and purchase of an on-line data reduction system for use at several of the General Motors test facilities. Specifically, a system was developed to reduce data collected according to the California Exhaust Emission schedule. Data reduction is accomplished by electronic analog computation with digital control and output. Gas analyzers convert the hydrocarbon, carbon monoxide, and carbon dioxide composition of exhaust gas into analogous electrical signals. There are averaged by time scaled integration at specific times during the driving cycle. At the end of a given time the electrical analog data is operated on according to a specified equation. The accumulation of data during the schedule provides the information used for the final average values of HC and CO.
1967-02-01
Technical Paper
670568
J. Robert Tewell, Charles H. Johnson
A new EVA/IVA simulation technique in which a servo-driven/computer-controlled simulator provides motion to the astronaut equivalent to that experienced in a zerog environment is described. The instrumentation systems required to generate the necessary input data to the analog computer, programed with the EVA/IVA dynamic equations, are discussed. The instrumentation consists of a load cell array to sense the forces and moments applied to the spacecraft by the astronaut during orbital activity and a unique limb motion sensor that continuously measures the astronaut's limb positions. The design considerations for the simulator are presented, and various space missions conducted on the simulator, with primary emphasis on EVA, are discussed.
1967-02-01
Technical Paper
670534
Homer W. Carhart
Highly complex mixtures of organic vapor pollutants are found in the atmospheres of both nuclear submarines and SeaLab II. There are continuing sources of these and they must be removed by proper use of activated carbon or by catalytic burning. In both craft the concentration of methane increases with time because it is not removed easily and there are continuing sources. Tobacco smoking in submarines generates large quantities of carbon monoxide which is catalytically burned. Its presence in significant quantities in SeaLab II is not fully explained. The low oxygen concentration in SeaLab precludes fires.
1967-02-01
Technical Paper
670199
Albert G. Lucas
Abstract A review of past development progress, the basic engine design problem, and the design status of today's engine indicates that the continued development of the four cycle, reciprocating piston, spark ignition automobile powerplant means continued improvements and the creation of a more difficult task for possible replacement. The years of development time have resulted in significant improvements in four areas: higher rotative speeds and improved thermal, volumetric, and mechanical efficiencies. Continued development and refinement of this engine will be stimulated in the future with catalytic development efforts similar to one we are presently experiencing - reduction of exhaust emissions. This effort is discussed in addition to the overhead camshaft valve mechanism and aluminum engines which are also subjects of current development interest.
1967-02-01
Technical Paper
670200
J. G. Gleason, J. J. Faitani
Abstract Intensive investigation of the effect of design features of jet engine combustors with regard to the formation of smoke has been performed by Pratt & Whitney Aircraft during recent years. This paper discusses the effect on the intensity of smoke formation observed by changes of such factors as primary air distribution, burner shape, swirlers, premixing, vaporizing, and so forth. A brief discussion concerning the effects of such variables as pressure, inlet temperature, and the like is presented, as is some discussion on the possibility of needed compromise between smoke abatement and performance factors.
1967-02-01
Technical Paper
670224
A. W. Carey
Abstract Black smoke is composed of free carbon or soot in an otherwise transparent exhaust stream. This paper discusses the factors responsible for smoke formation, the measurement of smoke, causes of excessive smoke on the highway, and the effect of fuel on smoke formation. Finally the role of smoke suppressant additives is described.
1967-02-01
Technical Paper
670093
C. O. Miller
The use of diesel smoke suppressant additive (SSA) provides an effective method of suppressing black smoke formation in 25 different makes of engines tested both in Europe and the United States. A proposed mechanism is offered to explain the smoke suppressing action of the additive. The additive also reduces carbon deposits, provides antiwear protection for injectors and piston rings, and may offer a modest increase in fuel economy. Fleet tests covering more than 4,000,000 miles of operation have proved the value of SSA. Exhaust gas analyses are substantially unchanged by the use of SSA. Animal feeding and respiratory tests on the exhaust solids from engines using SSA-treated fuel show negligible toxicity. Additional benefits of SSA include better storage stability, improved antistatic properties, and antibacterial protection.
1967-02-01
Technical Paper
670092
D. W. Golothan
Even though the combustion gases of diesel fuel are much less toxic than those of gasoline, exhaust smoke has increased proportionately with the number of diesels in use and has become a major problem. This paper describes the influence of base fuel composition on smoke, and the results of using a barium-containing additive in the fuel. The toxicological aspects of using the additive are considered, together with certain other side effects that might arise. Details are also given of the various means for measuring smoke, and of existing legislation to control the nuisance.
1967-02-01
Technical Paper
670091
G. McConnell, H. E. Howells
This paper examines the question of whether or not significant improvements in the condition of a diesel engine's exhaust can be practically achieved by altering the quality of the fuel. Engine test results from a variety of investigations are presented, and they are examined on a fuel quality/exhaust quality basis. Black smoke, white smoke, odor, oxides of nitrogen, and carbon monoxide are the exhaust constituents discussed in conjunction with fuel volatility, viscosity, and ignition quality. It is suggested that a change in base fuel quality is not, at present, a practical means of insuring an improvement in exhaust condition.
1967-02-01
Technical Paper
670089
H. W. Pearsall
In order to simulate diesel exhaust of known composition, weighed amounts of various high-boiling hydrocarbons were evaporated into a stream of heated air. These mixtures were sampled continuously and the hydrocarbon contents measured with a heated flame ionization detector (FID). The evaporator unit and FID were operated at various temperatures and 375 F was optimum as regards percentage of input material accounted for (85–100%, for paraffins through C16), fast response, and repeatability. The FID was then used at various temperatures to measure total hydrocarbons in exhaust from a 1-cyl diesel engine. Again, 375 F was optimum for obtaining maximum apparent hydrocarbon concentration, fast response, and repeatability. Finally, FID measurements were obtained at 375 F on exhaust from the engine at various operating conditions, to assess the effects of operating variables on hydrocarbons. Increasing compression ratio and temperatures of the inlet air and crankcase oil were effective ways of lowering hydrocarbons.
1967-02-01
Technical Paper
670122
H. K. Newhall, E. S. Starkman
A theoretical and experimental investigation was carried out to determine the mechanism whereby nitric oxide is formed, conserved, and exhausted from the reciprocating engine combustion chamber. The equipment utilized a magnesium oxide window to transmit the infrared radiation from the combustion chamber; a monochrometer to disperse the radiation, and a cryogenically cooled semiconductor to sense and indicate the nitric oxide produced radiation. The results confirmed the theoretical prediction based on chemical kinetics that nitric oxide, once formed in approximately equilibrium quantities in the combustion process will thereafter not disappear because the engine expansion takes place more rapidly than the kinetic processes can accommodate. The theory and measurements allow more rational explanations for the well documented influences which mixture strength, spark timing, compression ratio, and engine speed exert on oxides of nitrogen concentration in engine exhaust.
1967-02-01
Technical Paper
670123
P. E. Oberdorfer
A method for the sampling and determination of exhaust aldehydes and ketones is described. The procedure consists of absorbing and converting these compounds to the solid 2, 4 di-nitrophenylhydrazone derivatives. Results are reported as total aldehydes and/or the derivatives separated into individual, identifiable components by chromatographic techniques. Exhaust emission data employing this procedure are presented for a limited number of vehicles with and without exhaust control systems. Total aldehyde levels (as formaldehyde) were found to range from about 20 to over several hundred parts per million depending on the mode of operation and the adjustment of such variables as air-fuel ratio, spark timing, and exhaust emission control devices. Effects of these variables on aldehyde emissions are discussed. The relationship of the chemical structure of inducted fuel to aldehyde emissions is also touched upon. The amount of individual aldehydes was found to be related to the parent fuel to a considerable extent for pure individual hydrocarbon fuels.
1967-02-01
Technical Paper
670124
W. A. Daniel
Both the mechanism of individual hydrocarbon emission and the effects of engine variables on the individual hydrocarbon concentrations in the exhaust were investigated using a laboratory, single-cylinder engine with propane as the fuel. Individual hydrocarbon concentrations were measured, with a gas chromatograph, in samples obtained from the combustion chamber as well as from the exhaust system. Results indicate that, at the conditions investigated, a source of each of the individual hydrocarbons in the exhaust is the reaction (or lack of reaction) which occurs near the wall either at the instant the flame is quenched or immediately thereafter; however, cracking of the fuel hydrocarbon in the chamber after flame passage and in the exhaust pipe may also be a source of the non-fuel hydrocarbons. Relative proportions of fuel and non-fuel hydrocarbons in the exhaust are very sensitive to engine operating conditions. Total hydrocarbon concentration changes resulting from engine variable changes do not necessarily reflect, even directionally, changes in the individual hydrocarbon concentrations in the exhaust.
1967-02-01
Technical Paper
670125
John T. Agnew
Experimentally determined and theoretically calculated concentrations of unburned fuel in the exhaust products of a combustion system amenable to theoretical calculations have been compared. Propane-air mixtures were spark-ignited in the center of spherical combustion bombs of various sizes. By this means, the relative importance of the quench phenomenon (a surface effect) has been evaluated. The results show that simple application of quench theory is not consistent with the experimental results. Use of a modified quench theory, based on the results from the bomb experiments, for theoretical calculations of unburned hydrocarbon in engine exhaust indicates that the exhaust unburned hydrocarbon concentration from a large-displacement, low-compression ratio engine should be much lower than that of a small-displacement, high-compression ratio engine.
1967-02-01
Technical Paper
670126
D. T. Wade
The basic factors influencing carburetor and fuel tank evaporative emissions are explored. These factors are combined in a mathematical model to predict the magnitude and composition of evaporative losses. A laboratory technique for simulating carburetor losses is also described.
1967-02-01
Technical Paper
670127
P. J. Clarke, J. E. Gerrard, C. W. Skarstrom, J. Vardi, D. T. Wade
An approach to the containment of evaporative emissions of hydrocarbon fuel from automotive vehicles, using an adsorption system, is described. The concept of the system is based upon controlled adsorption-desorption cycling phased to engine operation modes. Feasibility is shown for both the containment of hydrocarbon vapors which would normally be lost to the atmosphere, and the feeding of these vapors to the engine under conditions such that both exhaust emissions and engine operation are unaltered. Extensive performance data are furnished on three cars equipped with exhaust control devices, and system design is treated in a semiempirical fashion demonstrating the flexibility of the approach.
1967-02-01
Technical Paper
670128
J. C. Gagliardi
The effect of fuel anti-knock compounds and combustion chamber deposits on exhaust hydrocarbon emissions was investigated. Six Ford Galaxies equipped with production non-Thermactor 289-CID, 2V engines were operated on a light-duty driving schedule for periods of 12–30,000 miles at Ford’s Michigan Proving Grounds. Three fuel blends were used in mileage accumulation—Indolene Clear (a full boiling range nonleaded gasoline), Indolene 30 (Indolene Clear + 3.0 ml/gallon of motor mix blend), and Indolene 30 + 0.2 theory of an organic phosphorous compound. Two engine lubricants were evaluated for the first 12,000 miles — a petroleum base SAE-10W-30 used for Ford factory fill and a synthetic oil, di-2-ethyl hexal sebacate. After 12,000 miles, all test engines were operated on the petroleum base lubricant. Exhaust emissions were monitored at 3,000-mile intervals on the chassis dynamometer using the CMVPCB* seven-mode procedure. Additional seven-mode cycles were conducted on each engine after combustion chamber deposits were removed at the completion of the mileage accumulation phase.
Viewing 22051 to 22080 of 22470

Filter

  • Article
    1065
  • Book
    75
  • Collection
    38
  • Magazine
    499
  • Technical Paper
    20183
  • Standard
    610