Transient emission simulation and optimization of turbocharged diesel engine

Abstract

In order to alleviate the pressure of experimental research of turbocharged diesel engine under transient operations, a whole process simulation platform for turbocharged diesel engine under transient operations was established based on the multi-software coupling technologies of Matlab/Simulink, GT-Power, STAR-CD and artificial neural network. Aimed at the contradiction of NO_x and soot emission control with exhaust gas recirculation (EGR) of turbocharged diesel engine under transient operations, on this simulation platform, a transient EGR valve control strategy was proposed, which adjusted the EGR valve in adjacent level based on the feedback of its opening according soot control limit under transient operations. Simulation and experimental results prove that the transient emission optimization effect of this control strategy is obvious. On the one hand, compared with the previous control strategy, which closed the EGR valve during the whole transient operations, soot emission is slightly increased by 9.5%, but it is still 9% lower than the control limit. On the other hand, compared with the previous control strategy, NO_x transient emission is reduced by 44%.

Key words： diesel engine; transient simulation; emission; control strategy; exhaust gas recirculation (EGR)

Acknowledgements

This work was supported by the Hi-Tech Research and Development Program of China (No. 2013CB228402) and the National Natural Science Foundation of China (Grant No. 50976046).

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