Analysis of combustion in marine diesel engines using CFD (Computational Fluid Dynamics)

The reduction of energy resources, the burning of fossil fuels, the harmful effects of gases products causing greenhouse effect, global warming, the widening of national and international regulations and areas of use have made it necessary to reduce harmful gases and to improve performance of diesel engines. Increasing performance and decreasing emissions in diesel engines are the main objectives. In order to generate energy in this area, alternative fuels with less environmental impact must be used or the engine geometry and fuel systems must be modified. In this study, the different injection timing in diesel engines which has one cylinder, four strokes. and the effect of the same amount fuel of fuel injection duration on engine performance and exhaust gas emissions were investigated by Computational Fluid Dynamics (CFD) method. Numerical data were verified in three different mesh structures and three different chemical kinetic mechanisms, and the validity of the results was checked by experimental studies for the same engine technical specification in the literature. For the standard operating conditions of the diesel engine modelled in the study, the combustion chamber velocity profiles, mass change of fuel, temperature, pressure, chemical heat release rate were determined. Nine different parametric studies were performed for different injection timing and injection duration. For each parametric study, performance parameters such as power, IMEP, engine torque and quantities of chemical components such as carbon dioxide, nitrogen oxides, unburned hydrocarbons have been determined. The study shows that numerical studies can be achieved with less time and cost than with experimental studies, with appropriate working conditions of diesel engine being determined.