A Study of Dual-Diluted Control Strategy for NG Engine

NG engine which was popularized in the past two decades has better performance of emission and less operating cost comparing with engines consuming traditional fuel. To meet stricter emission regulations, some outer purifier methods (e.g. SCR) are applied but at the expense of increasing cost. Some research illustrated “dual-diluted” combustion mode, which is achieved by the fresh air dilution and recirculated exhaust gas (EGR) dilution, a better “inter purifier” method. In this paper, Propose and develop a model based EGR control strategy with an in-cylinder lambda model to realize “dual-diluted” combustion mode. The results show that the exhaust dilution rate and fresh intake air dilution rate can be calculated accurately. Meanwhile, through these two models, the “duel-diluted” combustion mode is realized.