Combustion and pollutant emissions from light duty Diesel engines: the influence of mixing process and transient operating conditions

The influences of transient operating conditions and mixing process on exhaust emissions of the direct injection (DI) diesel combustion system are pointed out. With the use of a transient dynamic facility the combustion process was characterized and the combustion parameters were employed in order to explain the emission behaviour of the engine. With the joint use of three dimensional modeling and field experiments two different combustion system were compared and the emission behaviour was fully explained. Finally a mixing parameter was defined allowing a more useful use of 3-D calculations to the design of the combustion system.