Abstract
Air pollution around heavy traffic road is a major environmental problem especially in urban area. For the determination of appropriate road structure and/or for the application of some kind of air purification system to prevent serious pollution in the vicinity of the road, it is necessary to know the details of turbulent diffusion process of vehicle exhausts within the roadway. In this study, a series of numerical experiments was executed to estimate vehicle-induced turbulence and its influence on pollutant dispersion. Movement of each vehicle was represented by numerical grids explicitly. Patterns of mean velocity, turbulent intensity and mean concentration distributions within the roadway were compared between one-way and two-way facing traffic cases. Comparison was also made for some crosswind cases. In the lee side of roadway, vertical dispersion coefficient estimated in our simulation showed good agreement with that of stability-D value in Pasquill-Gifford classification.
