Potential Advanced Engine Technologies for Efficiency Improvement and Emissions Reduction

An outlook on the lines of the technological evolution that the Spark lgnition and the Diesel engine must undergo in order to meet the increasing demand for improved fuel economy of the 2000's in given. Considering the past three decades time frame the major issue was the large scale introduction of electronic control systems. Until the late 60s control of the engine output was accomplished through some combination of mechanical, pneu,atic or hydraulic systems (varburettor, breaker/distributor, Diesel injection pump). The request from the legislation to regulate emissions levels, implied the necessity to increase the accuracy and flexibility of engine control systems, leading to a fast increase of the electronically controlled injection systems. As regards the gasoline engines, the Drect injection into the combustion ??????? will overcome the present drawbacks of part Fuel injection and has a wide potential for fuel consumption reduction. The Electronic value Control technology has the potential to improve both powertorque density and fuel economy. Substantial fuel economy improvement could be moreover obtained by the development of a modular engine cooling system, capable of controlling the engine temperature at the optimum level in any operating conditions. The introduction even if on a limited scale of the CNG technology could give a valuable contribution to the CO2 emission reduction of Spark ignition engines. The Direct injection Diesel engines will benifit from the availability for mass production of the Common Rail fuel injection system with full electronic control. This breakthrough technology will help to solve the problem of noise and barshness, that limited till now the diffusion of these very efficient engines on passenger cars. The ???????? concept, the advanced cooled EGR, the DeNOx catalyst and the next generation Common Rail system are the major ley technology under development to allow these engines to meet the emission standards requirements for the 2000's.