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In continued studies with full-scale engines on the laboratory dynamometer, the effect of the engine variables air-fuel ratio, ignition timing, and rate of exhaust gas recirculation on octane requirement increase and exhaust emissions was studied in two engines at two compression ratios. A lead-free base gasoline was used in all tests, and a test procedure previously shown to relate well with road tests was followed. In both engines, ignition timing and rate of exhaust gas recirculation were found to have appreciable effects on octane requirement increase. Air-fuel ratio had an effect in one engine but not the other. The effect of compression ratio was mixed.

This paper presents the development of a computer model to simulate fuel usage and emission contributions of the past and future truck and bus population in the United States. The projected future years are beyond 1976 to 1990. The trends in vehicle population growth, yearly miles traveled and ton-miles are also calculated by the model. The model developed is flexible and brings together several technical concepts which reflect recent inputs from industry and government. The formulation of the model is based on a systems approach, in which the several submodels (the "Population," "Mileage," "Fuel Usage," and "Emission") are interrelated. The preliminary quantitative results are discussed to demonstrate the satisfactory performance of the computer model. Increased rates of dieselization are analyzed to determine their effect on reducing fuel consumption and the impact on total emission contributions. The use of the computer model to study an urban area for air quality is discussed.

A vehicle fleet test has been conducted to determine if octane advantages due to selected cooling system variables persist with stabilized deposits. The variables tested were reduced coolant temperatures, a direct substitution of aluminum for the iron cylinder head and an aluminum head with Unique Cooling. Octane requirements, octane requirement increase (ORI), emissions and fuel economy results are presented and discussed. Engine tests to determine the sensitivity of octane to independently controlled engine temperatures confirmed the primary dependence upon coolant temperature. Additional tests identified some of the variables which cause octane differences among the cylinders of one engine and between engine families.

Mr. Donald Friedman was developing vehicle concepts at GM from 1960 to 1968 and has continued this research since then as president and founder of Minicars, Inc. He has participated in the development of urban electric cars, the DOT/AMF/ESV, passive restraints and structural energy management programs. Mr. Friedman is presently in charge of systems analysis and integration of the Minicars Research Safety Vehicle Program.

Occupant protection was the focal point of the first work in the area of experimental safety vehicles. These first vehicles were heavy and expensive. The second generation of vehicles were designed with more realistic safety features and the goal for mass production. Complying with the modified objectives, the ESVW II was designed by Volkswagenwerk.

Test methods to evaluate the effects of engine oil formulations on fuel economy were evaluated using a variety of experimental and commercial oils. The oils were tested in a motor driven engine which showed reduced power requirements for low viscosity oils at low temperatures and friction reducing additives at high temperatures. A single cylinder engine generator was able to show trends for improved fuel economy with friction reducing additives. Automotive engine dynamometer tests were run at several operating conditions and showed fuel economy improvements for low viscosity oils and for oils containing friction reducing additives. Data from vehicles tested on an All Weather Chassis Dynamometer provided an excellent simulation of field service. The laboratory test procedures correlated well with results obtained in the chassis dynamometer.

The Research Safety Vehicle (RSV) Program is a four phase effort to develop a lightweight advanced safety vehicle design suitable for family transportation in the 1985 time period. The vehicle design is intended to be compatible with current production techniques, fuel efficient, non polluting, recyclable, and affordable. During Phase I and Phase II of the program, vehicle specifications were established and design concepts evaluated via computer simulations and full scale testing. The program is currently in the third phase of activity. The vehicle design developed in Phase II is being optimized and ten final vehicles fabricated.

The injury criteria measured in belted dummies in frontal barrier crash tests are compared to results from two alternative evaluation methods: Sled tests and mathematical simulation. The recorded values from the barrier crash tests and sled tests are compared by two different statistical inference tests in order to establish a possible significant difference between the methods. It is shown that results from barrier crash tests compare well to the results from sled tests except for the injury criteria, SI and HIC, of the driver. Only the passenger's situation was simulated mathematically and the results compare well to the results from a barrier crash test except for the HIC number.

The performance of three way and NOx catalysts was evaluated on vehicles utilizing non-feedback fuel control and electronic feedback fuel control. The vehicles accumulated 80,450 km (50,000 miles) using fuels representing the extremes in hydrogen-carbon ratio available for commercial use. Feedback carburetion compared to non-feedback carburetion improved highway fuel economy by about 0.4 km/l (1 mpg) and reduced deterioration of NOx with mileage accumulation. NOx emissions were higher with the low H/C fuel in the three way catalyst system; feedback reduced the fuel effect on NOx in these cars by improving conversion efficiency with the low H/C fuel. Feedback had no measureable effect on HC and CO catalyst efficiency. Hydrocarbon emissions were lower with the low H/C fuel in all cars. Unleaded gasoline octane improver, MMT, at 0.015g Mn/l (0.06 g/gal) increased tailpipe hydrocarbon emissions by 0.05 g/km (0.08 g/mile).

The widening of the selectivity windows of a three-way catalyst under A/F ratio modulation was shown to result from retention of adsorbed species on catalyst surfaces and their subsequent reaction with gas-phase reactants. A reaction model was developed based on adsorption properties of CO, HC and NOx and by computer simulation, the conversion efficiencies of CO, HC and NOx under A/F ratio modulation were calculated. The calculated and experimental results were in good agreement.

This is the third and final communication in this series of laboratory evaluation of three-way catalysts. The effect of inlet NO concentration and temperature on the NH3 formation over fresh, pulsator-aged and dynamometer-aged three-way catalysts of the current generation has been investigated under temperatures and exhaust compositions of practical interest. In spite of differences in aging procedures employed, both the pulsator and dynamometer-aged catalysts show similar selectivity behavior. The effect of SO2 in feed-gas on gross NO conversion and NH3 formation was studied over Pt-Rh and Pt-Rh-Ru types of three-way catalysts. A strong dependence of the gross NO conversion on the SO2 concentration in exhaust gas mixtures was noted. A simultaneous suppression of gross NO conversion and NH3 formation, in presence of SO2 in feed-gas, is attributed to the poisoning of Pt sites on aged three-way catalysts.

Experimental work was done to examine the interrelationships among automotive fuel economy, ambient temperature, cold-start trip length, and drive-train component temperatures of four 1977 vehicles. Fuel economy, exhaust emissions, and drive-train temperatures were measured at temperatures of 20, 45, 70, and 100° F using the 1975 Federal test procedure and the Environmental Protection Agency's highway fuel economy test. Results showed that vehicles used for short cold-start trips consume fuel at a much greater average rate than during long trips, and the effect is magnified with decreasing ambient temperature.

Using five single-component, three dual-component and five full boiling range fuels, the relationship between engine startability under low temperature and fuel volatility was experimentally studied. The study was carried out through the analysis of fuel vaporization and mixture formation in the cylinder. The effect of other factors such as cranking speed, ignition timing and fuel quantity supplied to the cylinder on startability was also examined from the view point of fuel vaporization in the cylinder. A theoretical approach for estimating the startability with fuels of various volatility was attempted. Based on this estimation, the degree of cold startability deterioration with lower volatility fuels and the way to improve cold engine startability were discussed.

The effects of fuels having atypical distillation characteristics on the driveability, fuel economy, and emissions of vehicles equipped with a variety of power plants were studied. The power plants included conventional, stratified charge, port fuel injected, and lean-burn engines. The atypical distillation fuels reflect the effect of removing varying amounts of mid-range or front-end blending components from a typical commercial gasoline. An index system was developed which allows a comparison of fuel effects across a fleet of vehicles differing substantially in terms of driveability, fuel economy, and emissions. Using this index system, the fleet average results show that emissions and fuel economy as well as driveability are depreciated with the extreme atypical fuels and that improved driveability can result in improved emissions and fuel economy.

Fuel volatility and cold/hot engine driveability relationships were evaluated in six 1976/1977 model cars representing conventional carburetor and advanced type fuel metering systems. The program objective was to provide guidance for engine modifications to take advantage of fuel benefits or to overcome performance deficiencies. There were large variations among cars in the maximum volatility tolerance relative to vapor lock during summer, hot engine operation, with a fuel-injected and a new design carburetor system tolerating gasoline volatility levels in excess of normal maximum summer levels. Similarly, cold engine start and driveaway performance at low and intermediate ambient conditions varied widely. Fuel-injected cars showed the best performance and least sensitivity to gasoline volatility changes. Performance differences among all cars with a specific fuel were significantly greater than differences resulting from typical variations of fuel volatility for individual cars.

This paper reviews the airline requirements for advanced aircraft technology in the period 10-20 years hence. Primary emphasis is placed on developments necessary to minimize fuel consumption in order to both offset expected increases in fuel prices and to prepare for the day when the supply of jet fuel may become restricted. The paper also reviews the probable developments in the pricing and marketing of the airline product and the consequent effects on the demand of the airlines for very high speed aircraft such as the SST and very long range aircraft such as the 747SP.

The Department of Transportation (DOT)/Federal Aviation Administration (FAA) has developed a valuable noise-simulation computer-based tool for describing and defining the impact of aircraft noise around an airport. This tool, the Integrated Noise Model (INM), became available to the public in 1977, and is useful in assessing actual or predicted airport noise impacts. The INM takes into account all pertinent impact parameters including types and numbers of aircraft operating at the airport, flight tracks, operating procedures, and time of day of aircraft operations. This paper will familiarize the reader with the capabilities and characteristics of the INM.

The formal definition of a Hub Airport, according to federal authorities, is an airport which enplanes over .05 percent of the total enplaned domestic airline passenger traffic in the United States during a given year. Hub Airports may be subdivided into categories of Small, Medium, and Large Hubs and these category classifications are dependent upon the number of passengers enplaned. As advances are made in airport design and air traffic control techniques, it may be expected that small aircraft, reciprocating engine aircraft of less than 12 500 lb, can be better assimilated into the environment of a Hub Airport without unduly burdening the total aircraft operating system.

Procedures and charts are presented to develop index numbers for reporting airfield bearing strength. Upon completion of an assessment of airfield bearing strength by the airfield authority, the results are reported as an index number that is a measure of the airplane effect on the pavement system. For reporting purposes, the airplane variables of wheel load, wheel spacing, and tire pressure, and the pavement variables of type (rigid, flexible, or composite), and subgrade strength characterization (strong, medium, low, and extra low strength) are related by means of two theoretical stress/deflection distributions: Westergaard for rigid pavements and modified Boussinesq for flexible pavements.

This report presents the results of an investigation to determine the causes of low utilization of angled runway exits on air carrier airports, to identify feasible measures to increase their utilization and to assess the probable resultant increase in runway capacity. The areas considered included aircraft runway occupancy time and travel time influence factors including taxiway networks, landing and deceleration procedures, cornering acceleration constraints, approach profiles and present and possible improvements in future supportive equipment such as glide slope and approach control. No field data was collected.