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In this paper, a marine dual fuel diesel engine fueled with the natural gas (NG: 60%, 70% and 80%) ignited by the biodiesel-diesel blended fuel (25%, 50% and 75% biodiesel by volume) was studied under different conditions. Based on the experiment, a computational fluid dynamics (CFD) model was established, and an improved chemical kinetic mechanism was developed to simulate the fuel spray process and combustion process. The ignition, combustion and emission characteristics of diesel engine fueled with different blended fuels were investigated under different load conditions. In addition, the temperature sensitivity of methane mole fraction with different NG energy fractions was analyzed at the 800 K and 1000 K. The results showed that the additions of NG and biodiesel in the blended fuel had a significant effect on the combustion and emission characteristics of the diesel engine. The starting of combustion (SOC) of the dual fuel engine lagged with the increases of NG and biodiesel content. The maximum enhancement of SOC reached 0.72°CA. The biggest influence on temperature was R122, which was the main reason for the shorter ignition delay during the combustion process. In all cases, NO x , CO and soot emissions decreased with increasing NG energy fraction. The maximum values of NO x , CO and soot emissions reached 1590 ppm, 461 ppm and 1.42 E−07 kg. Considering the combustion and emission characteristics of the engine, the best fuel blending ratio was EF80-B25. • A marine dual fuel diesel engine fueled with the natural gas ignited by the biodiesel-diesel blended fuel is investigated. • An improved 3D model and chemical kinetics mechanism are developed. • The optimum fuel mixture ratio of diesel engine is obtained. • The temperature sensitivity of methane mole fraction with different NG energy fractions is analyzed. [ABSTRACT FROM AUTHOR]

• The development of higher alcohols of modern automobile engines is listed. • The improvements of higher alcohols characteristic are discussed. • Optimization applications in diesel engine are investigated. • Improvement suggestions for performance enhancement of diesel engine are proposed. The application of oxygenated alternative fuels in diesel engines is an effective way to solve the energy crisis and environmental pollution. Higher alcohols (butanol and pentanol), as oxygenated and renewable fuels, are considered as new promising alternative fuels for diesel engine due to their good physicochemical properties and excellent combustion and emission characteristics in engines. The combustion is a complex process and has a significant impact on performance and emission characteristics of compression ignition (CI) engines. There are complicated relationships among CI engine, environment and fuel physicochemical properties, which interacts with each other. Therefore, it is important to investigate the synergistic effects of alternative fuels and their additives on CI engines. In recent years, the research on the advanced alcohols and its additives had made great progress. However, few people have reviewed the synergistic effect of higher alcohols and its additives on diesel engines. Therefore, this paper takes the combustion, performance and emission aspects of higher alcohols and its additives on the diesel engine as a starting point. Firstly, the physicochemical properties and preparations of higher alcohols are described, and their advantages are highlighted. Then, the effects of higher alcohols and its additives on the combustion, performance and emission characteristics of CI engines are summarized in terms of neat fuel, dual-fuel injection and multi-fuel blends, exhaust gas recirculation (EGR), injection strategy and advanced combustion mode. Finally, some important conclusions and discussions on the future development and experimental research direction are put forward, which will be helpful for the research on the use of higher alcohol in CI engines. [ABSTRACT FROM AUTHOR]