Performances of a DI Diesel engine with CR injection system,burning fuels of different quality

In this paper some preliminary results on the emission performances of a modern DI diesel engine, equipped with a CR injection system, and fed by some reformulated diesel fuels are discussed. The engine employed in the tests was a Fiat M724 1910cc, installed on Alfa Romeo 156 1.9 JTD. Two high quality fossil fuels and a synthetic fuel were selected for the tests. With common rail systems, the soot increase, due to the EGR, is evident only at relative low rail pressure while at high injection pressure the soot emissions are not influenced by the EGR rate. The main characteristic of engine equipped with CR system appears a moderate sensibility of NOx emissions and a poor particulate dependence from fuel quality.