Development and Experiments of an EGR System for a Supercharged Direct-injected Diesel Engine

For reducing NOx emission of diesel engines, an electronically controlled EGR system was developed based on a supercharged, inter-cooled DI diesel engine. The effects of EGR rates on the performances and emissions of the engine were researched by engine tests, and the EGR rates at ECE R49-13 modes were determined according to the test results for meeting the EURO II emission standard. An electronically controlled EGR system was designed and used to control the EGR rates in different conditions. The dynamometer tests showed that by the EGR control system, the NOx emission of the engine was reduced by 19.9% with the other emissions increased slightly.