北京道路工况下公交车PM和NOx排放特性试验研究

摘要

利用综合性车载排放测试系统完成北京典型柴油公交车在道路工况下排放特性的试验研究.结果表明,匀速行驶工况下的NOx排放率与车速呈正线性相关；平均车速为13.3km/h的低速拥堵工况的NOx排放因子是平均车速为41.1km/h的高速畅通工况的近两倍；研究表明,在低速加速的起步过程和低负荷工况下出现较严重的PM排放,须针对这两种工况优化发动机的燃烧品质.%An experimental study is conducted on the emission characteristics of typical public diesel bus in real driving condition in Beijing by using integrated portable emission measurement system. The results show that the emission rates of NOX exhibit a linear relationship with vehicle speed in cruising condition; while the emission factor of NO, in low-speed traffic jam condition with an average speed of 13. 3 km/h is nearly twice higher than that in high speed clear road condition with an average speed of 41. 1 km/h. The study also indicates that relatively severe PM emission appears in low-speed starting acceleration period and low load condition so the combustion quality of engine in these both conditions must be optimized.