Considering the Effects of Cyclic Variations when Modeling the Performance of a Spark Ignition Engine 2001-01-3600

An approach for simulating cyclic variations in spark ignition engines is described. It is based on a stochastic modeling coupled to a comprehensive model developed for predicting engine performance, mainly for gas-fueled engine applications. Such an approach is shown capable of generating cycle to cycle variations of pressure-time development records that are in good agreement with experiment. An account of the corresponding extent of cyclic variation in major performance parameters can be also established. It is demonstrated that the probability of the incidence of knock can be determined for any set of operating and design conditions while using this approach with sufficiently comprehensive detailed chemical kinetics. Examples involving mainly methane operation are shown.