路网机动车排放因子测算与不确定性分析

为分析交通指数和排放因子的测算机理，选择以速度为衔接点，首先研究交通指数下的速度分布测算方法和速度对排放因子的修正关系；其次，研究交通指数下的路网机动车排放因子测算方法，并分析排放因子的不确定性量化方法；然后，以北京为例，测算交通指数下的路网交通排放因子.结果表明:当路网交通指数位于2~8之间时，CO2排放因子随交通指数的增长而平稳增加，但交通指数在 (0.6, 2]和 (8, 9.4]时，CO2排放因子随交通指数的增长而快速增加.最后，统计了不同聚类方法下的排放因子偏差率，发现按工作日节假日和上下午分类后，交通指数下的CO2、CO、HC、NOx排放因子平均偏差率分别从3.48%、6.67%、6.08%、6.68%下降至2.65%、5.35%、5.20%、5.36%.
To analyze the influencing mechanism between traffic performance index (TPI) and emission factors, the speed distribution was taken as the connection variable.Firstly, a method for calculating speed distributions on different TPIs was established, and the relationship between the speed and emission factors was analyzed.Secondly, a method to calculate emission factors on road network was developed based on different TPIs, and a quantification method was analyzed to estimate the uncertainties.Thirdly, traffic emission factors on different TPIs were calculated for Beijing city.Results show that when the TPI is between 2 and 8, CO2 emission factor increases monotonously with the increase of TPI.However, when TPI is between 0.6 and 2 or between 8 and 9.4, CO2 emission factor increases rapidly.Finally, the average deviation rates of emission factors under different clustering results were calculated.It was concluded that by classifying the data from 4 aspects, workday, weekend, AM, and PM, the deviation rate of emission factors CO2, CO, HC, NOx decreased from 3.48%, 6.67%, 6.08%, 6.68% to 2.65%, 5.35%, 5.20%, 5.36% respectively.