Development of a Universal Turbulent Combustion Model for Premixed and Direct Injection Spark/Compression Ignition Engines

A universal engine combustion model based on the level-set approach was developed in this study. It was first used to model combustion in Spark Ignition (SI) and Direct Injection Spark Ignition (DISI) engines when combined with the Discrete Particle Spark Ignition model, in which the ignition kernel is represented by particles. Once the flame kernel grows to a size that the turbulent flame is fully developed, the G-equation model is used to track the subsequent propagation of the turbulent flame. When combined with a characteristic time combustion model, the triple flame structure that is found in DISI engine combustion was successfully modeled. The model was also applied to simulate diesel combustion where the diffusion combustion regime is dominant. In this case, the ignition was modeled using the Shell auto-ignition model. Satisfactory agreement with features of the conceptual diesel combustion model of Dec [1997] was found. Thus the present model presents a universal combustion modeling methodology for all combustion regimes, that is called the GAMUT (G-equation for All Mixtures • a Universal Turbulent) Combustion model.