急速二段燃焼によるディーゼル機関のNO_x低減

抄録

Rich-lean rapid two-stage combustion was attempted to reduce NO_x from the diesel engine. The effect of the mixture concentration and its history on NO formation was evaluated using a thermo-chemical three-zone model. The experimental study was also carried out using a small direct-injection diesel engine with high turbulent combustion system. Fuel-rich mixture was formed by two small cavity combustion chambers. Dimethyl Ether was used to form uniform rich mixture and to avoid smoke formation. The results show that NO_x can be reduced in the heavy load when the mixture concentration shifts to lean from rich condition in a short period.