Effects of Octane Number of Gasoline Fuel on Ignition and Combustion Processes in a Dual-Fuel Compression Ignition Engine

Abstract

This paper investigated the change of the ignition and combustion processes in a dual-fuel compression ignition engine while changing the octane number of primary reference fuel which was injected into an intake port. The experiments were implemented by use of a single cylinder engine for in-cylinder pressure analysis and evaluation of engine performance. The experimental result showed that octane number of premixed fuel can affect not only the ignition timing but also the bulky combustion rate, and the effect could be pronounced when advancing direct injection timing with smaller amount of diesel fuel. Furthermore, the detailed combustion process was evaluated through a combustion visualization performed in a rapid compression and expansion machine.