Effects of Ethanol Addition on Ignition Characteristics for Homogeneous Charge Compression Ignition Gasoline Engines

-An Experimental Study of the Effects of Ethanol Addition on Gasoline HCCI Combustion and an Analysis of the Reaction Mechanism by using the Chemical Kinetics Calculation-

Abstract

Homogeneous charge compression ignition gasoline engine in which ethanol-gasoline blends are used substitute for gasoline, ignition timing is retarded compared with gasoline's one under low engine speed conditions. However, as engine speed becomes high, tendency of ignition timing reversed in experiments. This phenomenon depends on in cylinder temperature, and it was understood that difference of initial dissociation and low temperature oxidation reaction between ethanol and gasoline largely affects this phenomenon by using detailed chemical kinetics simulation.