大跨屋盖结构形体多为复杂曲面,荷载规范的规定往往不能满足设计需求,风荷载的确定需借助于其他手段,而CFD数值模拟是近年来兴起的一种风荷载研究手段.本文基于FLUENT平台,对厦门文化艺术中心共享综合楼屋顶膜结构进行了数值风洞试验研究,湍流模型采用雷诺应力(RSM)模型.数值模拟结果表明,膜结构表面风压分布与其表面形状密切相关,在曲率变化大的局部区域风压变化也很剧烈,在设计时需引起相当重视.同时结合屋盖周围的流场特点,对屋盖表面平均风压的分布规律进行了分析,并根据不同风向下风压分布特性对膜结构表面进行了分区,并给出可供工程设计参考的分区风载体型系数.基于以上工作,说明CFD数值模拟为复杂工程提供辅助设计信息是可行的.
Due to the complexity in shape of long span roofs, codes in Chinese Load Standards are not enough for design, and CFD simulation is a newly developed research method for wind loading. In this paper, mean wind pressures of the membrane roof of Art & Culture Center building in Xiamen are computed based on FLUENT software platform with Reynolds Stress Model (RSM). Numerical simulation results show that the characteristics of wind loads on roofs have close relation with the shape of roofs. The mean wind loads vary greatly in the regions where the curvature of membrane is obviously changed and the designers should pay more attention to these regions. are discussed based on simulation results. Finally, The flow characteristics around membrane structures according to the contours of wind pressure under different wind directions, the membrane roofs are divided into several sub-regions and corresponding wind pressure shape coefficient of each region is provided as a reference for design. Above works proof it is feasible to provide additional information for design by using CFD simulation.