Cylinder Process Simulation with Heat Release Analysis in Diesel Engine

The use of thermodynamic models for the simulation of the cylinder process from analyzing heat release has been a common practice as a way to predict the performance of internal combustion engines. However, it is of importance to apply a suitable heat release model, as well as the gas properties, fuel properties, heat loss models, etc. In this paper, in order to distinguish two stages of combustion process, a double Vibe model is used to determine the heat release rate and a systematic investigation of the influence of several parameters in it to the pressure and temperature in cylinder is carried out. In addition, the Woschni heat transfer coefficient model is used to determine the heat loss to the cylinder wall during combustion. The gas properties, such as gas constant, specific heat and lower heat value are acquired by determining the components of air, stoichiometric gas and fuel, and using the mass fraction of air in the working gas as parameter. The reliability of the model has been verified by using a 4-stroke diesel engine MAN 4L20/27 to simulate in MATLAB/SIMULINK and the result of the simulation model is coincident with the actual operating condition of this engine.