Study On Nitrogen Oxide Emission Characteristic Of Marine Diesel Engine By Means Of GT-POWER

At present, the problem of environment pollution draws people's attention increasingly. The international communities and organizations establish relevant laws to restrict the emission and reduce the harm to human and entironment. Marine vessel is one of removable contaminated sources, establishment of law about its emission control is mentioned on schedule. The code of air pollution prevention which is the Annex VI of the International Convention for The Prevention of Pollution from Ships takes effect from May 2005. It means that the demand about NO_X-emission of marine diesel engine becomes more rigorous, then all kinds of methods of controlling NO_X-emission of marine diesel engine appear. By means of GT-POWER, simulating a diesel engine work process, this paper mainly analyzes qualitatively and quantitatively the NO_X-emission characteristic of marine diesel engine.First, this paper introduces the ship's emission and the influence on the propulsion machinery of marine diesel engine by limit law.Next, this paper analyzes diesel engine NO_X-emission theory and the factor of NO_X-emission, then introduces NO_X-emission control methods.Then, this paper introduces the process of establishing diesel model by GT-POWER. Taking the 6210Z_LD-5 engine as an example, this paper establishs diesel burning model to simulate the combustion. Comparing the simulated results with the experimental results, it proves the utility of GT-POWER software. Using the software instead of experimentation, this paper accounts the effect of NO_X-emission and diesel performance when the angle of start injection changes, compression ratio changes and the technology of spraying water and adding wet is adopted.Finally, according to the results of simulative computation, the paper gives out the measure of reducing NO_X-emission in environmental pattern, provides the advice for the operation and management of marine diesel engine.