Release Time:2019-03-13 Hits:
Indexed by: Journal Article
Date of Publication: 2016-04-01
Journal: ENERGIES
Included Journals: EI、SCIE
Volume: 9
Issue: 4
ISSN: 1996-1073
Key Words: 2-stroke marine diesel engine; combustion; emissions; Miller-cycle; EGR
Abstract: The authors applied one-dimensional (1-D) simulation and 3-D Computational Fluid Dynamics (CFD) simulation to evaluate the potential of in-cylinder control methods on a low-speed 2-stroke marine engine to reach the International Maritime Organization (IMO) Tier 3 NOx emissions standards. Reducing the combustion temperature is an important in-cylinder measure to decrease NOx emissions of marine diesel engines. Miller-cycle and Exhaust Gas Recirculation (EGR) are effective methods to reduce the maximum combustion temperature and accordingly decrease NOx emissions. The authors' calculation results indicate that with a combination of 2-stage turbocharging, a mild Miller-cycle and 10% EGR rate, the NOx emissions can be decreased by 48% without the increased Specific Fuel Oil Consumption (SFOC) penalties; with a medium Miller-cycle and 10% EGR, NOx can be decreased by 56% with a slight increase of SFOC; with a medium Miller-cycle and 20% EGR, NOx can be decreased by 77% and meet IMO Tier 3 standards, but with the high price of a considerable increase of SFOC. The first two schemes are promising to meet IMO Tier 3 standards with good fuel economy if other techniques are combined.