Performance and emission evaluation of a marine diesel engine fueled by water biodiesel-diesel emulsion blends with a fuel additive of a cerium oxide nanoparticle

In this paper, the study investigates the combined application of water additive and metal-based additive in the biodiesel-diesel blend fuel. Varied mixtures of biodiesel- diesel (B5), water (i.e. 2%, 4% and 6% wt.) and cerium oxide (CeO2) nanoparticles (90 ppm) components are compared with pure diesel in terms of their combustion emissions and performance. The experiments are carried out on a marine medium-speed diesel engine. The results showed that the water additive in the biodiesel-diesel fuel was beneficial to improving the mixing of air and fuel due to the micro-explosion. Nevertheless, by further increasing water additive to 6%, the effect of micro-explosion would be dominated by the impact of increased viscosity leading to combustion deterioration. Proper water additive is beneficial to improving performance and decreasing the CO, PM, NOx and HC emissions. As well as the metal-based additives in the blend fuels can further improve the overall combustion quality and decrease the emissions. More specifically, the metal-based additives are beneficial to improving the brake power and brake thermal efficiency (BTE) and decreasing the brake specific fuel consumption (BSFC) and emissions due to the improved combustion caused by the catalytic activity during the combustion process. Thus, the relationship between the additives and performance and emission characteristics of blend fuel is very important.