Technical Paper
Effects of Direct Injection Timing and Air Dilution on the Combustion and Emissions Characteristics of Stratified Flame Ignited (SFI) Hybrid Combustion in a 4-Stroke PFI/DI Gasoline Engine
2020-04-14
2020-01-1139
Controlled Auto-Ignition (CAI) combustion can effectively improve the thermal efficiency of conventional spark ignition (SI) gasoline engines, due to shortened combustion processes caused by multi-point auto-ignition. However, its commercial application is limited by the difficulties in controlling ignition timing and violent heat release process at high loads. Stratified flame ignited (SFI) hybrid combustion, a concept in which rich mixture around spark plug is consumed by flame propagation after spark ignition and the unburned lean mixture closing to cylinder wall auto-ignites in the increasing in-cylinder temperature during flame propagation, was proposed to overcome these challenges.
