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Downsizing as a main-stream technology was widely used for design of future diesel engines in order to meet the increasingly stringent demands of emissions regulation and reduction of CO2 production. Design of intake system faces a considerable challenge accordingly. Discharge coefficient and swirl ratio as two main factors of intake port design have been widely investigated by researchers. However, these two parameters indicate a trade-off relationship. Therefore, it is difficult for a classical intake system to achieve a good balance between sufficient air charge and decent air-fuel radial mixing quality. A 1 L twin-intake-port single-cylinder diesel engine was studied in this paper. A swirl control valve designed to adjust the effective flow area of the filling port, was installed between the intake manifold and the intake filling port in order to achieve variation of swirl ratio. And there is no control valve for the intake spiral port.

2, 5-Dimethylfuran (DMF) has been receiving increasing interest as a potential alternative fuel to fossil fuels, owing to the recent development of new production technology. However, the influence of DMF properties on the in-cylinder fuel spray and its evaporation, subsequent combustion processes as well as emission formation in current gasoline direct injection (GDI) engines is still not well understood, due to the lack of comprehensive understanding of its physical and chemical characteristics. To better understand the spray characteristics of DMF and its application to the IC engine, the fuel sprays of DMF and gasoline were investigated by experimental and computational methods. The shadowgraph and Phase Doppler Particle Analyzer (PDPA) techniques were used for measuring spray penetration, droplet velocity and size distribution of both fuels.

2,5-dimethylfuran (DMF) is currently regarded as a potential alternative fuel to gasoline due to the development of new production technology. In this paper, the spray characteristics of DMF and its blends with gasoline were studied from a high pressure direct injection gasoline injector using the shadowgraph and Phase Doppler Particle Analyzer (PDPA) techniques, This includes the spray penetration, droplet velocity and size distribution of the various mixtures. In parallel commercial gasoline and ethanol were measured in order to compare the characteristics of DMF. A total of 52 points were measured along the spray so that the experimental results could be used for subsequent numerical modeling. In summary, the experimental results showed that DMF and its blends have similar spray properties to gasoline, compared to ethanol. The droplet size of DMF is generally smaller than ethanol and decreases faster with the increase of injection pressure.