The development of the internal combustion engines with the high efficiency is required these days. HCCI engine is one of the most promising and eco-friendly engines. In HCCI engine, premixed oxydizer and fuel are compressed in the combustion chamber and autoignitied. HCCI has some advantages compared to conventional diesel and gasoline engines, such as low soot emission, low NOx emission, high thermal efficiency.

However, controlling of ignition timing is very difficult, which limits the operation range of HCCI. In our laboratory, controlling the ignition using PFJ (Pulse Flame Jet) is proposed. Effects of PFJ on the ignition knocking behavior are investigated.

Fig. 1 RCEM (Rapid Compression Expansion Machine) for HCCI experiment
Fig. 2 HCCI ignition. PFJ is injected from the left side