Cycle Simulation for a Spark Ignition Engine Using a Turbylent Combustion Model

A computer model is developed to predict engine performance and exhaust emissions in a spark-ignition engine. In the model, combustion phenomenon is analyzed by the turbulent combustion model which considers the effect of the turbulence and the combustion chamber on combustion. The gas exchange process is calculated by one dimensional isentropic flow through a nozzle. During combustion, 13 products are obtained by chemical equilibrium, and nitric oxide (NO) formation is calculated by the extended Zeldovich mechanism. The results of the computer model are compared with the experimental results. The calculated values for pressure and NO emission show good agreement “with the experimental data. The effects of the engine speed, spark timing, air fuel ratio, and EGR are studied by the model.