Large eddy simulation of wind load on low-rise buildings subjected to downburst

The large eddy simulation method was used to study the wind load characteristics of low-rise buildings under the action of unsteady thunderstorms. The following aspects were analyzed to study the influence on the wind load of the building in different development stages of the downburst: the radial position of the building, the roof slope and the wind direction angle, etc. Results show that there are significant differences in wind load effect at different development stages. When the first ring vortex generated by the airflow hitting the ground blows over the building, the wind load of the building is the most unfavorable. While the building is in different radial positions, the transient wind pressure caused by the ring vortex passing through the building is quite different from that caused by the steady downburst at the same position. The slope of roof has less influence on the distribution of wind pressure coefficient in the windward roof, but great influence on that in the windward side roof. When the slope of the roof increases, the wind pressure coefficient of the windward roof gradually changes from negative value to positive value. The wind pressure coefficient for the corner of the windward front of the building is obviously affected by the wind direction angle. In the tested condition, the influence is most significant when the wind direction angle is 45°. © 2020, Zhejiang University Press. All right reserved.