An analysis on combustion and emission characteristics of a diesel engine fuelled with f-t synthetic diesel fuel

An experimental study on the combustion and emission characteristics and particulate size distribution feature of a turbocharged inter-cooled high-pressure common rail diesel engine fueled with coal-based Fischer-Tropsch synthetic diesel fuel (F-T diesel fuel) is conducted to analyze the effects of F-T diesel fuel on the combustion and emission of engine. The results show that compared with State-V diesel fuel, when F-T diesel fuel is used with the same injection strategy, engine torque reduces due to its lower density, meanwhile as its main constituent is straight-chain alkane, which increases its cetane number with good ignitability, the ignition delay period shortens, the heat release in premixed combustion stage reduces, and the combustion temperature in cylinder lowers, helping to reduce the emission of NOx, and its good combustion characteristics make the emissions of CO and HC and smoke opacity greatly lower. With 13-mode test cycle, the weighted specific emissions of CO, HC and NOx decrease by 51.42%, 45.62% and 14.35% respectively, and under different load conditions the total number emission of particulates and the proportions of ultra-fine particulates and nucleation mode particulates totally reduce. All these have great significance in meeting increasingly stringent emission regulations. © 2016, Society of Automotive Engineers of China. All right reserved.