Effect of ethanol on auto-ignition characteristics and laminar burning velocity of gasoline under elevated temperature and pressure

Gasoline and its surrogate fuels have developed rapidly in recent years, and the study of the theory of multi-fuel mixed combustion is vital to the improvement of power machines. On the basis of the important role of ethanol-gasoline mixtures in oxygenated alternative fuels, Cai and Pitsch’ s mechanism was selected for a numerical study to research the important role of ethanol with respect to combustion of gasoline from a chemical kinetic perspective. It is found that the addition of ethanol accelerates the LBV and shortens the IDTs of gasoline, and the LBV of ethanol-gasoline mixtures goes up as both the initial temperature and the ethanol ratio rise, while the LBV of ethanol-gasoline mixtures declines as the initial pressure increases. The IDTs of ethanol-gasoline mixtures tend to decrease as the initial temperature, ethanol ratio and initial pressure increase. The addition of ethanol increases the production of the intermediates CH3, HCO and CH2O, and the reactive radicals in the system increase with the addition of ethanol. In addition, the addition of ethanol can lead to an earlier surge of OH groups. This study is not only helpful for the design of ethanol-gasoline power engines, but also promotes the development of alternative fuels.