龙卷风作用下四坡屋面建筑风荷载特性数值模拟研究

Numerical simulation study on wind load characteristics of buildings with hip roof under tornado

文章基于计算流体动力学(computational fluid dynamics,CFD)数值模拟,采用剪切应力传输(shear stress transport,SST)k-ω湍流模型对龙卷风作用下的四坡屋面低矮建筑风荷载进行模拟研究,针对多个龙卷风方位角,分析获取不同坡角和有、无挑檐时建筑表面风压分布规律以及分区风载体型系数。结果表明:建筑背风屋面始终承受风吸力作用,并随着屋面坡角增加,风吸力不断增大;随着坡角增加,迎风屋面受荷形式由受风吸力为主转变为受风压力为主;整体来看,挑檐的存在有利于减小四坡建筑屋面的龙卷风荷载作用。

Based on the computational fluid dynamics(CFD)numerical simulation,shear stress transport(SST)k-ωturbulence model was used to simulate the wind load on the hip roof of low-rise buildings under tornado.According to the tornado azimuths,the distribution of wind pressure on the building surfaces and the wind load shape coefficient of various roof regions are obtained under different slope angles with or without the eaves.The results show that the leeward of the building is always bearing the wind suction,and the wind suction increases with the increase of the angle of the roof.With the increase of slope angle,the load-bearing form of windward roof changes from the wind suction to the wind pressure.Overall,the existence of overhanging eaves is conducive to reducing the tornado load on the hip roof of low-rise buildings.