EGR control and simulation about EGR rates influence on diesel engine operation performance

According to the basic structure of actual diesel engine, a control project and simulation model of TDI diesel engine with EGR system was established. Based on the optimum EGR rates map of diesel engine test experiment as control map of EGR control unit, the simulation on EGR control unit was constructed. The engine rotated speed and load signals was transferred to EGR mass flow coefficient signal from Boost program to Matlab Simulink and then called back to Boost program. Therefore, the simulation process about the influence of EGR rates on the whole diesel engine operation process was actualized, provided that EGR rates was continuously changing with diesel engine rotated speed and load when EGR was used in diesel engine. It is proved by simulation results that A/F ratio, cylinder pressure, the temperature in the cylinder and exhaust gas temperature are lower than the original and the gas mass in the cylinder is higher than the original when EGR is used in the diesel engine, but exhaust gas temperature, pressure and EGR mass flow of each cylinder is different when EGR rates are steady, the results also prove that there are deficiencies in the actual diesel engine intake manifold which lead to the uneven distribution of intake air mass and EGR gas in each cylinder, the results were also analyzed.