CAJ | 학술논문

利用CONVERGE软件研究不同压缩比和EGR率对预混压燃（PCCI）柴油机燃烧和排放的影响规律。在1650 r/min转速50%负荷下，采用小喷油锥角和4次多脉冲预喷射喷油策略实现PCCI燃烧。结果表明，降低压缩比能够显著推迟缸内着火时刻，强化油气混合，同时降低NOx和干碳烟的排放，但油耗会提高；随着EGR率的增大，缸内着火延迟时间越长，燃烧爆发压力、缸内平均温度、瞬时放热率峰值和缸内压力升高率则相应降低，同时NOx排放下降，干碳烟排放升高，油耗升高。
이용CONVERGE연건연구불동압축비화EGR솔대예혼압연（PCCI）시유궤연소화배방적영향규률。재1650 r/min전속50%부하하，채용소분유추각화4차다맥충예분사분유책략실현PCCI연소。결과표명，강저압축비능구현저추지항내착화시각，강화유기혼합，동시강저NOx화간탄연적배방，단유모회제고；수착EGR솔적증대，항내착화연지시간월장，연소폭발압력、항내평균온도、순시방열솔봉치화항내압력승고솔칙상응강저，동시NOx배방하강，간탄연배방승고，유모승고。
The effects of different compression ratio and EGR rate on combustion and emission of PCCI diesel engine are studied with software CONVERGE. In the condition of 1 650 r/min speed and 50% load, the PCCI combustion is realized by using small injection cone angle and 4 multi pulse pre-injection fuel injection strategy. The results show that, lowering compression ratio can significantly delay the PCCI diesel engine’s ignition timing, enhance diesel and gas mixing, reduce NOx and soot emission, whereas at the expense of rising fuel consumption. With the increase of EGR rate, the ignition delay of PCCI diesel engine increases, and combustion firing pressure, average temperature, the peak value of heat release rate and the pressure rise rate decline accordingly, meanwhile NOx emission goes down and soot emission rises, and fuel consumption goes up.