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The requirement of reduced emissions and improved fuel economy led the introduction of direct-injection (DI) spark-ignited (SI) engines. Dual-fuel injection system (direct-injection and port-fuel-injection (PFI)) was also used to improve engine performance at high load and speed. Ethanol is one of the several alternative transportation fuels considered for replacing fossil fuels such as gasoline and diesel. Ethanol offers high octane quality but with lower energy density than fossil fuels. This paper presents the combustion characteristics of a single cylinder dual-fuel injection SI engine with the following fueling cases: a) gasoline for PFI and DI, b) PFI gasoline and DI ethanol, and c) PFI ethanol and DI gasoline. For this study, the DI fueling portion varied from 0 to 100 percentage of the total fueling over different engine operational conditions while the engine air-to-fuel ratio remained at a constant level.

Elastohydrodynamic lubrication, piston dynamics and friction are important characteristics determining the performance and efficiency of an internal combustion engine. This paper presents a finite element analysis on a production piston of a gasoline engine performed using commercial software, the COSMOSDesignStar, and a comprehensive cylinder-kit simulation software, the CASE, to demonstrate the advantages of using a reduced, parameterized model analysis in the assessment of piston design characteristics. The full piston model is parameterized according to the CASE specifications. The two are analyzed and compared in the COSMOSDesignStar, considering thermal and mechanical loads. The region of interest is the skirt area on the thrust and anti-thrust sides of the piston.