北京城区河岸带的物理结构对交通污染物扩散特征影响的模拟

Simulation of the effects of physical structures of riparian buffers on dispersion of traffic pollutants in urban areas of Beijing

以北京城区北护城河为例,探讨具有不同物理结构的河岸带对交通污染物扩散特征的影响.结果表明,在不同季节,不同物理结构的河岸带对应不同的ρ分布和最大质量浓度落地点xρmax,表现出不同的影响.其中,与线源水平方向上的距离对xρmax的影响最大,但需结合其他因素综合分析xρmax在河岸带或河流中的相对位置;与线源垂直方向上的高度H对ρ和xρmax均有影响.同时,线源源强和气象参数(如大气稳定度和风速)对交通污染物的扩散特征也有影响.

This study explores the effects of physical structures of riparian buffers （RBs） on the dispersion of traffic pollutants in north moat of Beijing. The results show that the RBs with different physical structures correspond to different distributions of ground concentrations of traffic pollutants （ρ） and different landing locations with the maximum concentration （xρmax） in different seasons. Specifically, the horizontal distance between RB and line source has the strongest effect on xρmax, and the vertical distance between RB and line source has also effects on both p and xρmax.