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IJME 286

Paper title: Computational Fluid Dynamics Analysis of NOx Reduction by Ammonia Injection in the MAN B&W 7S50MC Marine Engine



M I Lamas, C G Rodríguez and J D Rodríguez, University of Coruña, Spain, J Telmo, University of Santiago de Compostela, Spain


Taking into account the importance of NOx (nitrogen oxides) emissions from marine engines and the current increasingly restrictive legislation, this work aims to develop a numerical model to study NOx reduction. To this end, direct injection of NH3 (ammonia) into the combustion chamber was proposed in the MAN B&W 7S50MC marine engine. The numerical model was employed to analyze several injection temperatures, injection timings and ammonia to fuel ratios, obtaining NOx reductions of almost 60%. Besides, a comparison between ammonia injection and water injection was done. The results showed that ammonia is more efficient than water to reduce NOx with a negligible influence on other pollutants such as CO (carbon monoxide) and HC (hydrocarbons). Nevertheless, ammonia is efficient in a very restrictive temperature and injection timing range. This numerical model was compared with experimental measurements, obtaining satisfactory results which validate the work.


Transactions RINA, Vol 156, Part A3, International Journal Maritime Engineering, Jul-Sep 2014 

DOI Number

DOI No: 10.3940/rina.ijme.2014.a3.286

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