Modeling of Liquid Fuel Behavior in the Intake Port of SI Engines

A wall-fuel film flow model is developed to predict the effect of a wall-fuel-film to air fuel ratio in SI engines is transient conditions. Fuel redistribution in the intake port due to backflow and a simple liquid fuel behavior in the cylinder are included in this model.Liquid fuel film flow is calculated with every crank angle degree using the instantaneous air flow conditions. The model is validated by comparing the calculated results and corresponding engine experiment results with a commercial 4 cylinder DOHC engine. The predicted results match well the experimental results. to maintain the constant air-fuel ratio during the rapid throttle opening/closing condition, the fuel injection rate control can be obtained from the simulation results.