ABSTRACT
Compression-ignition engines operate with a heterogeneous air-fuel mixture. A mixture prepared during the ignition delay period is called a premixed charge, whereas a mixture preparation at the end of the injection period is called a heterogeneous mixture. Premixed charge compression ignition (PCCI) combustion is a hybrid combustion sandwiched between a homogeneous charge compression ignition (HCCI) and a conventional diesel combustion. HCCI is a form of low temperature combustion (LTC) in which a premixed charge gets autoignition in the engine cylinder. HCCI, which is a LTC strategy, is generally used for simultaneous reduction of oxides of nitrogen (NOx) and particulate matter (PM)/smoke emissions in compression-ignition engines. A compression-ignition engine in RCCI mode operates with two different kinds of fuels as high reactivity fuel for initiating ignition for combusting low reactivity fuel. Gaseous fuels such as biogas, producer gas, natural gas, LPG, and hydrogen could be utilized in a compression ignition engine in a dual-fuel mode.
