Various regulations have been introduced by International Maritime Organisation (IMO) to reduce NOX emissions of ships. There is a variety of emission reduction methods of these ships, which play an active role in the maritime industry. In this study, the design and NOX reduction performance of the SCR, which is a highly efficient after-treatment system in reducing NOX emissions, has been investigated. The investigation has been focused on the effect of the exhaust velocity and the Reynolds number change on the system performance for a marine diesel engine operating under two-stroke high-pressure conditions. The velocity and the Reynolds number in the model change depending on the SCR system diameter. The study was carried out numerically with the Computational Fluid Dynamics (CFD) method. The CFD method has been implemented under the experimentally taken operating conditions. As a result of the study, the pressure drop of the system, diameter-dependent velocity change and NOX reduction performance of the SCR have been determined. It was observed that due to the increase in the SCR system diameter, the exhaust velocity and the pressure drop decreased. Thus, the NOX reduction performance can be improved. The study has provided important information on determining the optimal SCR system diameter based on NOX reduction performance.
Anahtar Kelimeler: NOx emissions, Marine diesel engine, HP-SCR, UWS