Kinetic modelling of combustion in a spark ignition engine with water injection

Abstract This work models the impact of direct water injection on combustion process in a spark ignition engine. It uses two-zone kinetic model coupled with detailed chemistry to highlight thermodynamic and chemical-kinetic interactions between gasoline injection. The modelling results agree closely measurements from highly boosted, study first proposes an approach mass fraction burned (MFB) profile using representative in-cylinder pressure trace. derived MFB is then used as input for model. Within this model, predictive estimate knock limited advance (KLSA) baseline engine operating condition without subsequently, several conditions Predicted KLSA values obtained method measured results. Utilising developed study, modelled at was found be similar that water/fuel ratio (WFR) 60%. result likely due competing contrasting effects reduced temperature versus more advanced phasing Further analysis shows charge cooling effect afforded by much greater than dilution terms advancing phasing. Water also affects processes take place unburned gas zone, but mainly altering – injected not directly involved low it simply acts collision partner.