CAJ | 학술논문

在单缸直喷式柴油机上,研究了燃用柴油和柴油/丙烷混合燃料时,空燃比对发动机燃烧和排放特性的影响.结果表明:发动机转速一定时,燃烧持续期随空燃比和丙烷比例的增加而缩短;缸内最高燃烧压力随空燃比的增大而减小,随丙烷比例的增加而增大;NO_x和碳烟排放随空燃比的增大而降低,HC排放在小空燃比时随空燃比的减小而大幅度增加,而在大空燃比时随空燃比的增大而稍有增加;在小空燃比时CO排放随空燃比的减小而增加,在大空燃比时变化不大;燃用柴油/丙烷混合燃料可同时降低CO、HC和碳烟排放,但NO_x排放增加.
재단항직분식시유궤상,연구료연용시유화시유/병완혼합연료시,공연비대발동궤연소화배방특성적영향.결과표명:발동궤전속일정시,연소지속기수공연비화병완비례적증가이축단;항내최고연소압력수공연비적증대이감소,수병완비례적증가이증대;NO_x화탄연배방수공연비적증대이강저,HC배방재소공연비시수공연비적감소이대폭도증가,이재대공연비시수공연비적증대이초유증가;재소공연비시CO배방수공연비적감소이증가,재대공연비시변화불대;연용시유/병완혼합연료가동시강저CO、HC화탄연배방,단NO_x배방증가.
The effects of air-fuel ratio on the combustion and emissions of a single-cylinder direct injection diesel engine fueled with diesel fuel and diesel/propane blends were investigated. The results show that the combustion duration decreases with the increase of air-fuel ratio and propane proportion; the peak cylinder pressure decreases with the increase of air-fuel ratio and increases with the increase of propane proportion, NO_x and smoke emissions decrease with the increase of air-fuel ratio, HC emission increases greatly with the decrease of air-fuel ratio at smaller air-fuel ratio, while it increases with the increase of air-fuel ratio at larger air-fuel ratio; CO emission increases with the decrease of air-fuel ratio at smaller air-fuel ratio, and it almost keeps constant at larger air-fuel ratio; CO, HC and smoke emissions can be reduced simultaneously, but NO_x emission increases when the engine is fueled with diesel/propane blend.