Search Results

The impact of turbocharging on Diesel exhaust emissions has been investigated by studying, on a 4-cyl IDI Fiat engine different configurations including fuel injection optimization, exhaust gas recirculation and oxidant catalysts. The experimental results obtained during bench and chassis dynamometer tests were compared with the same tests performed on the naturally aspirated 4-cyl engine. Mathematical models were used in order to identify the regions giving the maximum contribution to regulated emissions. Particulate and organic adsorbed compounds were also measured. It appears that turbocharging can represent a reasonably good approach in order to achieve low levels of regulated emissions and particulates associated with high fuel economy.

A light weight diesel engine family having high specific power output (up to 21 KW/1) has been developed for medium trucks (7/13 ton) starting from existing 6-cyl in-line N/A and T/C DI engines with a single displacement equal to 0.915 liters. To meet future U.S. federal and California emission standards changes in combustion chamber shape, swirl level, injection system and turbocarger matching have been introduced. Projections of fuel economy according to the new transient procedure proposed by EPA have been carried out. These have been compared with the projections of a conventional gasoline engine referred to the same vehicles. Finally the main relationships among the combustion parameters, fuel consumption and emissions have been explored.