Simulation Research on EGR Reducing NO X Emission of Diesel Engine

The model of diesel engine and its EGR model were established in the AVL BOOST. The model's validity was verified by comparing with the data of engine bench test. The working conditions selected were 25%, 50%, 75% and 100% load under rated speed. Simulation results show that with the augment of the EGR rate, NOX emissions decreased. When the opening degree of the EGR change from 0 to 100%, the NOX of each working conditions decrease 46.23%, 42.2%, 33.97% and 32.3% respectively. At the same time, with the EGR valve opening increase, the reduction of NOX is extremely significant.