CAJ | 학술논문

　　采用 DMS500快速颗粒取样分析仪对一台缸内直喷国Ⅳ汽油机进行了颗粒物粒径分布特性的试验研究。结果表明：缸内直喷汽油机排气颗粒物呈包括核态和积聚态颗粒物的双峰分布，仅怠速工况呈核态单峰分布。随转速升高，总颗粒物数浓度在部分负荷下逐渐降低，外特性先降低后升高；随负荷增加，总颗粒物数浓度在中、低负荷下逐渐降低，满负荷时急剧增加。随转速升高，核态颗粒物在部分负荷速度特性下数密度峰值逐渐降低，外特性下先降低后增加；积聚态颗粒物数密度峰值逐渐降低。随负荷增加，核态颗粒物数密度峰值在中、低负荷时逐渐降低，满负荷时增加；积聚态颗粒物数密度峰值在中、低负荷时先升高后降低，满负荷时最高。
　　채용 DMS500쾌속과립취양분석의대일태항내직분국Ⅳ기유궤진행료과립물립경분포특성적시험연구。결과표명：항내직분기유궤배기과립물정포괄핵태화적취태과립물적쌍봉분포，부태속공황정핵태단봉분포。수전속승고，총과립물수농도재부분부하하축점강저，외특성선강저후승고；수부하증가，총과립물수농도재중、저부하하축점강저，만부하시급극증가。수전속승고，핵태과립물재부분부하속도특성하수밀도봉치축점강저，외특성하선강저후증가；적취태과립물수밀도봉치축점강저。수부하증가，핵태과립물수밀도봉치재중、저부하시축점강저，만부하시증가；적취태과립물수밀도봉치재중、저부하시선승고후강저，만부하시최고。
A DMS500 fast particulate spectrometer was employed to characterize the particle size distribution from a gasoline direct injection (GDI) engine, which meets the regulations of China Ⅳ standards. The results show that exhaust particulates from GDI engine are bimodal in form with nucleation mode particle and accumulation mode par-ticle, except for a unimodal nucleation mode particle which is shown in idle condition. With the increase in engine speed, the total particle number concentration increases gradually under the speed characteristics in part load condi-tion, but decreases after an initial increase in wide open throttle (WOT) condition. With the increase in engine load, the total particle number concentration decreases gradually in part load condition, but increases abruptly in full load condition. The peak value of number density for nucleation mode particle drops gradually under the speed characteris-tics in part load condition, but increases after an initial decrease in WOT condition with the increase in engine speed. The peak value of number density for accumulation mode particle shows a decreasing trend with the increase in engine speed. At the constant speed, the peak value of number density shows a gradually decreasing trend for nucleation mode particle and a dropping trend after an initial increase for accumulation mode particle as the load increases, except for an increasing trend for nucleation mode particle and a peak value for accumulation mode particle in full load condition.