Modeling intermediate and alternative fuel emissions in large two-stroke engines: Towards an accurate assessment of decarbonization impact

A range of non-conventional fuels are currently being considered for reducing greenhouse gas emissions from shipping. Modeling the emissions profile of these fuels can support the rapid development of engine concepts that assist decarbonization efforts. The goal of this study is to develop and test effective thermodynamic modeling frameworks which can predict (a) methane emissions from natural gas-operated engines, and (b) greenhouse gas and air pollutant emissions from ammonia-operated engines. The GT-Suite 0D/1D-CFD simulation software is used as the main framework for model development. Modeled emissions show generally good agreement with experimental measurements from large engines operated with Liquefied Natural Gas or diesel-ammonia mixtures.