الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 94 |  |  |
| | | from | 94 | | |
Abstract
Emissions from ships are a serious global issue due to their effects on environmental damage, particularly global warming of the atmosphere. As a result, the International Maritime Organization (IMO) places a high priority on environmental protection by reducing exhaust emissions by at least 50% by 2050. Among the IMO’s proposed measures, using alternative marine fuels such as natural gas and methanol instead of conventional fuels has been prioritised. In this study, a comparative study between converting diesel engine into dual fuel engine operated with alternative fuels such as methanol or natural gas is carried out. The numerical simulation for combustion is prepared on a 3D sector cylinder using ANSYS-FLUENT to calculate dynamic motion of air, and combustion characteristics. Then diesel/methanol dual-fuel combustion is performed to evaluate the distribution of essential mass fraction, operational temperature, and pollution formatted inside combustion engine such as NOx, SOx, and soot emissions. The model comprises of turbulence model, Radiation model, Moss–Brookes model for soot calculation, eddy dissipation model, and NO production model. The results show the swirl and tumble ratio to improve the combustion process and reduce emissions. For pollution effects, the study illustrates that NOx emissions of diesel/methanol including NO and N2O reduced by 57% and 65% compared with pure diesel fuel. In addition to the decrease in SOx and soot pollution by 52% and 53% respectively. The mass fraction for O, H, and CO is reduced by increasing the methanol ratio. The convergence between the CFD and experimental results refers to the ability of using numerical analysis in diesel engine design.