CFD analysis of the combustion process in a 4-stroke engine equipped with different passive prechamber using a detailed chemistry solver

The combustion process of a 4-stroke PFI gasoline engine equipped with a passive prechamber has been investigated through three dimensional CFD analysis. The goal was to analyse the behaviour of the flame front during the entire combustion process and to evaluate the improvements in terms of both combustion speed and ignitability of lean mixtures. The trade-off between the accuracy and complexity of the numerical approach and computational costs was assessed by adopting two different combustion models, with different detail level, for the simulation of the engine cycle: a detailed chemistry model and a flame surface density model.