Technical Paper
Simulation Study of Sparked-Spray Induced Combustion at Ultra-lean Condition in a GDI Engine
2024-04-09
2024-01-2107
Ultra-lean combustion of GDI engines could achieve a higher thermal efficiency and lower NOx emissions, but it also faces challenges such as ignition difficulties and a low-speed flame propagation. In this paper, the sparked-spray is proposed as a novel ignition method, which employs the spark to ignite the fuel spray by the cooperative timing control of in-cylinder fuel injection and spark ignition, and form a jet flame, and then the jet flame fronts propagate in the ultra-lean premixed mixture in the cylinder. This combustion mode is named Sparked-Spray Induced Combustion (SSIC) in this paper. Based on a 3-cylinder 1.0L GDI engine, a 3D simulation model is established in the CONVERGE to study the effects of ignition strategy, compression ratio, injection timing, equivalent ratio on SSIC with global equivalent ratio of 0.50.