大跨度屋盖风荷载的大涡模拟研究

应用一种新的湍流脉动流场产生方法DSRFG(discretizing and synthesizing random flow generation)模拟风场实际的湍流边界条件.采用一种新的大涡模拟LES(Large Eddy Simulation)的亚格子模型,基于linux系统下软件平台Fluent6.3的并行计算技术,计算了长沙机场扩建航站楼屋盖结构在5个风向下的风荷载.根据对机场屋盖的平均风压和脉动风压系数分布规律的分析,给出了各风向角下屋面的表面风压分布特性和最不利风向角,为长沙机场扩建航站楼的抗风设计提供了依据.并为进一步发展此类复杂建筑结构在复杂湍流环境下的风荷载数值风洞技术提供参考.

Large Eddy Simulation of Wind Loads on Long span Roofs

A new inflow turbulence generator called discretizing and synthesizing random flow generation was applied to simulate the actual boundary conditions of turbulent flow field. A new one equation dynamic subgrid scale (SGS) model was adopted for the large eddy simulations. The wind loads on the roof of Changsha Airport Extension Building with five wind directions were calculated on the basis of the paralleled technology of Fluent6.3 soft platform under the linux system. The distribution characteristics of the surface wind pressure on the roof and the most unfavorable wind direction were determined by analyzing the mean and fluctuating pressure coefficient contours. The results are valuable for the wind resistant design of Changsha Airport Extension Building and provide useful information for the numerical simulation of wind loads of other similar structures. The results show that the response trends are the same and the response is close, though different methods were used to simulate water body and different analysis methods were employed.