Modelling of Gasoline-Fuelled Passive Pre-chamber Combustion System

Pre-chamber combustion system is a promising engine technology that allows ultra-lean combustion with high thermal efficiency and low emission. The chapter reviews the mechanism and the state of the art in modelling passive pre-chamber combustion systems for gasoline engines. The ignition mechanism in the main chamber is investigated numerically. A design of pre-chamber is proposed and optimized using the three-dimensional computational fluid dynamics (CFD) simulation. An efficient optimization method based on the Bayesian updating strategy is introduced, which is employed to optimize the pre-chamber geometrical design. Three-dimensional CFD simulation coupled with the design of the experiment (DOE), genetic algorithm, and machine learning methods is used to optimize the pre-chamber with desired combustion phasing. Regression analysis shows that the radius of the pre-chamber is the most influential design parameter.