Detailed Spark Ignition Modelling applied to Compressed Natural Gas Engines

For compressed natural gas engines, the ignition and combustion processes need particular attention. In this work, an advanced spark ignition model is developed for application in the three-dimensional Computational Fluid Dynamics (3D CFD) simulation. Here the flame kernel development is modelled with chemical heat released by the air-fuel mixture and spark ignition parameters. Pre-calculated libraries of thermo-kinetic properties are used to couple detailed chemical kinetic mechanisms with this model. A cluster of Lagrangian particles caters to the effects of turbulence on flame kernel movement. The consecutive flame propagation is modelled with the G-Equation level set approach.
Extensive validation of this model is carried out with experiments spanning from a constant volume chamber, a rapid compression machine and a transparent engine to serial engines with open chamber and with lean prechamber spark ignition. The model is applied for broadly varied boundary conditions, including ultra-lean mixtures. With the help of different calculated parameters, this model can also predict rare events like a misfire and restrike beforehand.