Combined Impact of n-Butanol Additive and Spark Timing on Combustion and Efficiency of a GDI Engine

The influence of n-butanol additive and spark timing on the combustion process was studied in a gasoline direct injection (GDI) engine, as well as fuel efficiency and relevant performance indicators. Three concentrations of n-butanol blended fuels (i.e., Bu15, Bu30, and Bu50) were used as tested fuels and compared to regular gasoline at low and high loads. The results indicate that increasing the n-butanol concentration or advanced spark timing...