Effect of different combustion models and alternative fuels on two-stroke marine diesel engine performance

Different combustion models and alternative fuels can be used in simulations under the same operating conditions to study their effects on marine diesel engine performance. In-cylinder pressure and temperature, emission products (NOx, HC, CO, CO2), and the distributions of equivalence ratio, temperature and emission products were simulated. The simulation model was validated with experimental data. Errors in in-cylinder pressure and emissions were in the acceptable range. Results show that the maximum in-cylinder combustion pressure calculated using the detailed chemistry solver combustion model (SAGE) is closer to the experimental data than the results of others models. There is little difference in pressures between n-heptane and n-tetradecane in the same combustion model. The integrated heat releases are almost the same for the different models. However, the n-heptane-SAGE model has a larger error than do the other models for the quantity of NOx. Comparing the errors of NOx, HC, CO and CO2, the n-heptane-CTC/shell simulation model data are closest to the experimental data. The important element reactions of the alternative fuel mechanism needs to be adjusted to ensure the emissions are consistent with experimental data. Finally, the contours of temperature, equivalence ratio and emission products are validated by comparing the results of different models.