Applicability Analysis and Combustion Simulation of Ammonia as Fuel for Marine Diesel Engine

In order to cut down carbon dioxide emission from shipping industries, ammonia is proposed as an alternative marine fuel oil recently. The applicability of ammonia as marine fuel is firstly analyzed in this paper in the aspects of carbon reduction potential, maturity system, infrastructure, and economy. It is proved and shows that ammonia fuel is one of the best alternative fuels for ships in the long term. To understand the feasibility of ammonia fuel as a clean alternative fuel for ships in the future, three-dimensional combustion model of a diesel engine 4135Aca was established by Solid Works software and CONVERGE software. The combustion simulation blended with ammonia fuel was carried out, so that the combustion characteristics in cylinder and emission characteristics out of diesel engine were obtained. When 1%, 5%, 8% and 9% ammonia is injected into air intake port, the combustion pressure and temperature inside cylinder will increase, due to extra work of the diesel engine, while CO
2
emission decreases by 18.7%, because of the delayed ignition time. These results indicate that the injection of ammonia fuel can increase diesel engine power and reduce CO
2
emissions, but it also causes combustion delay and a little increase of NO
X
, which should be paid attention to in the future application of ammonia fuel on board ships.