A cetane number determining apparatus for a fuel of a diesel engine and a method for determining a cetane number of a fuel of a diesel engine

摘要

A minute amount of fuel is injected into a combustion chamber during fuel cut, and a cylinder pressure is detected when the minute amount of fuel is being combusted. Then a combustion ratio is calculated based on the detected cylinder pressure, and a determination crank angle, which is used for determining a cetane number based on the combustion ratio, is determined. The cetane number is determined based on the determination crank angle.