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Every fact of the world's automotive industry in undergoing fundamental change. This transformation is being prompted by a wide range of forces but is primarily associated with the increase in the international competition and rapid advances in technology. The world automotive market is growing far more slowly than production capacity. New entrants from countries such as Korea and Yugoslavia are further adding to the competitive pressures. Furthermore, rapid changes in both product and process technology and the engineering process arc causing a shift in the way vehicles are designed, developed, and produced. Consumers are increasing their demands for affordable, high quality vehicles with features designed to meet a variety of expectations. World class cost and quality are rapidly becoming tin- price of admission to the competition but, in themselves will not assure long term success.

The role of automotive electronics in light duty vehicles is continuing to expand rapidly. In this paper an overview of a 1986 Delphi forecast of major trends is presented. Trends discussed include electronics as a fraction of vehicle and component cost and projections of basic vehicle features supported by electronic technology. In addition, basic trends in diagnostics and multiplexing are presented. Several issues in support of automotive electronics are discussed, including the systems approach to vehicle engineering, the importance of developing a proper market strategy, and the continued major role of energy economics. The Delphi forecasting technique and its governing concepts are reviewed as a method to predict the future of automotive technology.

An experimental study of a divided-chamber, stratified-charge engine has been performed using a modified CFR L-head engine. Emissions and fuel consumption were measured over a wide range of overall fuel-air ratio and degree of stratification by varying the prechamber and main chamber inlet fuel-air ratios. High-speed motion pictures of the combustion process and the spatial distribution of fuel-air ratio in the combustion chamber, measured using a sampling valve, were used to explain the trends in the emissions data. Of particular interest is an increase in NOx emissions with increasing degree of stratification at lean overall fuel-air ratios.

A series of stable colloid lubricant additives have been evaluated for their influence on vehicle fuel economy through modification of engine friction. The SAE J-1082 procedure was used to determine fuel consumption in tests conducted in a seven vehicle fleet exercise which showed encouraging improvements in fuel economy, especially in the SAE Urban cycle. In addition, an extended dynamometer test was conducted on the most promising colloid additive system. After 100 hours of test at 55 mph (road-load), fuel consumption was reduced by approximately 2% and engine friction was inferred to have been reduced by more than 10%. Engine oils treated with these stable colloid additives hold the promise of effecting important fuel savings over the total existing vehicle population within a minimum time frame.

The Curtiss-Wright RC2-60 engine exhaust emissions were measured, with and without an exhaust reactor, under steady-state conditions at the University of Michigan and in a vehicle operated on the simulated California cycle at an independent facility. The reactor successfully reduced the emission levels in both cases. Data are presented for the steady-state trends of engine emissions as a function of engine performance variables; trends are generally similar to those of conventional gasoline engines. The particular effectiveness of an exhaust reactor with the RC engine is attributed to port characteristics and higher exhaust gas temperatures unique to this engine together with new reactor design features. Theoretical considerations and future investigations are discussed.

Cycle-to-cycle variation of pressure is a common problem in all spark-ignition engines. To examine the suspected influence of mixture-motion on this variation, a study was performed in a constant volume cylindrical bomb in which a jet of propane-air mixture was directed at the initial flame kernel. The rate of pressure rise of the jet-influenced combustion was compared to the rate for combustion in a quiescent mixture. The flame area, obtained using a spark schlieren photographic technique, and the calculated combustion rate were correlated with the pressure rate. The major results were: the rate of pressure rise increased approximately linearly with mixture jet velocity; and the width of the mixture-jet had an effect on the rate of pressure rise. A jet profile width slightly greather than the spark-gap produced the highest rate of pressure rise.