Ignition Characteristics of Methanol and Natural-Gas in a HCCI Engine Assisted by DME

In order to clarify ignition characteristics of a HCCI engine, methanol and natural-gas were burnt in a single cylinder diesel engine fuelling with DME as an ignition source. The effect of fuel cetane number on low temperature reaction(LTR), high temperature reaction (HTR), knock limit temperature and misfire limit were compared between methanol and natural gas. It is found that ignition temperatures of LTR and HTR is dependent only on cetane number of the fuel, however, the maximum heat release rate of LTR is dependent not only on cetane number but also the fuel composition.