2007 Volume 42 Issue 5 Pages 301-309
We conducted wind-tunnel experiments to study the effect of the heights and arrangements of roadside buildings on the flow and concentration fields in a street canyon.
For the four building arrangements studied (Figs. 3 and 4), the best transfer of pollutants from street level to the upper air was by a zigzag array of tall and short roadside buildings (Fig. 4, Type 4). In this, for a tall building on the windward side of the canyon, the ascending flow along the roadside (leeward) wall was accelerated. For a tall building on the leeward side of the canyon, the descending flow along the roadside (windward) wall was also accelerated.
These flows were linked together at the bottom of the canyon. Consequently, they formed a three-dimensional flow field in the canyon that efficiently carries air pollutants from the street-canyon bottom to the upper air.
