【摘要】 为研究轻型汽油车在南京市区道路上的细颗粒物排放特征,建立了车载测试系统.通过对比实际道路和底盘测功机测试结果探讨了机动车速度、加速度及行驶工况对细颗粒物排放的影响.实际道路下,加速状态下的车辆颗粒物数量、质量浓度明显高于其他行驶状态;在低速情况下,核模态(Dp<50 nm)细颗粒物数量浓度较大,高速条件下积聚模态(50 nm<Dp<565 nm)的颗粒数量较多.底盘测功机试验的颗粒物平均数量浓度为车载试验下的1.62倍,但质量浓度仅为车载试验的0.18倍.粒径100 nm以下的细颗粒物数浓度占整个测试的绝大部分.高速及急加速下,车辆会产生更多细颗粒物.结果表明:实际道路轻型汽油车的细颗粒物排放特性可用该车载系统来描述.更多还原

【Abstract】 To investigate the fine particle emission instantaneous characteristics of a single light-duty gasoline vehicle on Nanjing urban streets,an on-road system of chassis dynamometer was set up to analyze the influences of vehicle speed,acceleration and driving modes on fine particles size distributions.For the on-road measurements,the number and the mass concentration of particles under acceleration condition are obviously higher than those under other driving modes.At low speed,the number concentration of fine particle in nucleic mode(Dp<50 nm) is higher than that at high speed,while the particle numbers in accumulation mode(50 nm<Dp<565 nm) at high speed is more than that at low speed.The average total number concentration in the chassis dynamometer tests is 1.62 times than that in on-road measurements,while the ratio of average mass concentration to that in on-road measurements is only 0.18.The particle number concentration with diameter lower than 100 nm accounts for a vast majority of the test range.More fine particles are emitted under high speed and hard acceleration condition.The results show that the proposed system is effective to investigate the fine particle emission characteristics from a light-duty gasoline vehicle at real urban road.更多还原