DISPERSION OF VEHICULAR EMISSION IN STREET CANYONS, GUANGZHOU-CITY, SOUTH CHINA (PRC)

The concentration of vehicular pollutants, wind, turbulence and traffi c volume were measured in three different typical street canyons in Gu angzhou City. Air dispersion in different types of urban canyons was c ompared. The configuration of a street is an important factor that inf luences air dispersion. In low wind conditions, it is rare that a stab le vortex is formed in a canyon with irregular configuration. The move ment of vehicles may dominate the flow near the surface of the narrow street canyon when the wind at roof-level is weak. Simple operational models have been proposed. They performed well in predicting the air p ollution due to vehicular emission in different street canyons in Guan gzhou City.