Multizone Combustion Model For A Four Stroke Direct Injection Diesel Engine

An effort has been made in this work to understand the physical phenomenon behind combustion in DI diesel engine and to evaluate its performance through a mathematical model. The model developed consists of two phases - the spray model and the combustion model. In the spray model a 2-D axis-symmetric grid is considered. The spray dispersion, penetration, and the cells that are ready for ignition at the end of ignition delay are found from the spray model. Some of the empirical relations from wave break model and that available in the literature are used to model the spray. A numerical technique is used to solve the conservation equations of mass, momentum and energy in the combustion model to evaluate the properties at each crank angle. The model is also used to determine mass fractions burnt, pressure, temperature, heat release at each crank angle and performance parameters. To validate the simulation results, test has been conducted on a single cylinder four stroke Kirloskar DI diesel engine and a reasonable agreement is found between the computed and the experimental results.