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Ethanol is a promising alternative to fossil fuels because it can be produced from biomass resources that are renewable. Due to the amount of production, however, the usage would be limited to blends with other conventional fuels. Ethanol-fuel blends are azeotropic and have unique vaporization characteristics different from blends composed of aliphatic hydrocarbons, so that the present study developed a numerical scheme which takes into account the vapor-liquid equilibrium of azeotrope in order to update the author's original version of the multi-component fuel CFD model and to evaluate the effect of mixing ethanol into gasoline on the evaporation process. The numerical simulation was implemented for evaporating sprays of ethanol-n-heptane blends, which are injected through a single hole nozzle. In addition to the vapor-liquid equilibrium, the effect of the latent heat of vaporization was investigated.

Auto-ignition and combustion processes of dual-component fuel spray were numerically studied. A source code of SUPERTRAPP (developed by NIST), which is capable of predicting thermodynamic and transportation properties of pure fluids and fluid mixtures containing up to 20 components, was incorporated into KIVA3V to provide physical fuel properties and vapor-liquid equilibrium calculations. Low temperature oxidation reaction, which is of importance in ignition process of hydrocarbon fuels, as well as negative temperature coefficient behavior was taken into account using the multistep kinetics ignition prediction based on Shell model, while a global single-step mechanism was employed to account for high temperature oxidation reaction. Computational results with the present multi-component fuel model were validated by comparing with experimental data of spray combustion obtained in a constant volume vessel.

This paper describes application of sintered silicon nitride to the swirl lower-chamber in order to improve performance of turbocharged diesel engines. Various stress analyses by finite element method and stress measurements have been applied to determine the design specifications for the component, which compromise brittleness of ceramic materials. Material development was conducted to evaluate strength, fracture toughness, and thermal properties for the sintered bodies. Ceramic injection molding has been employed to fabricate components with large quantities in the present work. Quality assurance for the components can be made by reliability evaluation methods as well as non-destructive and stress loading inspections. It is found that the engine performance with ceramic component has been increased in the power out put of 9PS as compared to that of conventional engines.