Benefits With Common Rail Injection for Medium Speed Engines

The NOx emission of sea going ships is limited by the IMO. The black smoke emission is in the focus of the port authorities and the ship owners. More stringent limits are expected for the near future. Caterpillar Motoren decided to be pro active and to start an emission reduction program in the mid of the nineties. Inside the engine technology like: higher compression ratio, Miller Cycle, injection tuning and internal exhaust gas recirculation were investigated to reduce the NOx Emission. To lower the soot emission a Common Rail system was implemented. The effects of Pre-, Post- and Split injections were optimized for further emission reductions. A special trim of the injection characteristic can improve the transient load acceptance of the engine. A low emission strategy was defined. NOTE: This paper was presented at the ASME 2003 Internal Combustion Engine Division Spring Technical Conference but was printed in the ASME 2003 Internal Combustion Engine and Rail Transportation Divisions Fall Technical Conference proceedings, pages 443–454. It should appear under the CIMAC heading. © 2003 ASME