Experimental Investigation on Pedestrian-level Wind Environment Around a High-rise Building

Abstract:

The pedestrian level wind environment around a single square cross-sectional high-rise building （within 12 meters of bottom area） was investigated in the wind tunnel， and the distribution and variation of the parameters such as speed-up ratio and R_M （mean wind velocity ratio） at different wind direction angles were studied. Meanwhile， by employing the meteorological data of Guangzhou and the Lawson criterion of wind comfort， the pedestrian level wind environment under strong wind in this region was evaluated. The results show that the maximum speed-up ratios at different wind direction angles are approximately equal to 1.9， and all appear at the corner of the leeward side of the building. The areas with the R_M greater than 0.75 also appear at the corner of the leeward side of building， which is likely to cause pedestrian wind discomfort. Besides， the area of pedestrian wind discomfort is the largest when the wind direction is perpendicular to the wall. Attention should be paid to the increase of wind speed caused by the downwash effect at pedestrian level. In the wind direction angle range of 20 to 70 degrees， the area with unfavorable ventilation is quite large， which may cause adverse results in diffusion of air pollutants. The greatest gust equivalent mean wind speed appears at the corners of the windward and leeward sides of the building， and pedestrian activities in these areas should be restricted or reminded.