Prediction of auto-ignition delay in HCCI engine

Homogenous charge compression ignition (HCCI) engines are being actively developed worldwide as they can have efficiencies close to that of diesel engines, with low levels of oxides of nitrogen as we particulate matter emissions. There are challenges associated with the successful operation of HCCI engines particularly with combustion phasing controls. Thus, auto-ignition models are proposed to be used in engine control systems. Hu and Keck model, Shell model, and Knock integral method are selected. Two equations in Knock integral method are proposed for the prediction of start of ignition of the first- and second-stage combustion. The comparison of average differences in auto-ignition delay between the models, experimental data and time calculation indicates that Knock integral model has the highest accuracy as well as shorter time.